bluuebunny/crossref_metadata_2025 huggingface dataset:
A Game-Theory-Based Approach to Modeling Lane-Changing Interactions on Highway On-Ramps: Considering the Bounded Rationality of Drivers
Authors: Chen Weihan , Ren Gang , Cao Qi , Song Jianhua , Liu Yikun , Dong Changyin
Published: January 2023

In highway on-ramp sections, the conflictual interactions between a subject vehicle (merging vehicle) in the acceleration lane and a following vehicle (lagging vehicle) in the adjacent mainline can lead to traffic congestion, go–stop oscillations, and serious safety hazards. Human drivers combine their previous lane-changing experience and their perception of surrounding traffic conditions to decide whether to merge. However, the decisions that they make are not always optimal in specific traffic scenarios due to fuzzy perception and misjudgment. That is, they make lane-changing decisions in a bounded rational way. In this paper, a game-theory-based approach is used to model the interactive behavior of mandatory lane-changing in a highway on-ramp section. The model comprehensively considers vehicle interactions and the bounded rationality of drivers by modeling lane-changing behavior on on-ramps as a two-person non-zero-sum non-cooperative game with incomplete information. In addition, the Logit QRE is used to explain the bounded rationality of drivers. In order to estimate the parameters, a bi-level programming framework is built. Vehicle trajectory data from NGSIM and an unmanned aerial vehicle survey were used for model calibration and validation. The validation results were rigorously evaluated by using various performance indicators, such as the mean absolute error, root mean square error, detection rate, and false-alarm rate. It can be seen that the proposed game theory-based model was able to effectively predict merging and yielding interactions with a high degree of accuracy.
Multiple UAVs Path Planning Based on Deep Reinforcement Learning in Communication Denial Environment
Authors: Xu Yahao , Wei Yiran , Jiang Keyang , Wang Di , Deng Hongbin
Published: January 2023

In this paper, we propose a C51-Duel-IP (C51 Dueling DQN with Independent Policy) dynamic destination path-planning algorithm to solve the problem of autonomous navigation and avoidance of multiple Unmanned Aerial Vehicles (UAVs) in the communication denial environment. Our proposed algorithm expresses the Q function output by the Dueling network as a Q distribution, which improves the fitting ability of the Q value. We also extend the single-step temporal differential (TD) to the N-step timing differential, which solves the problem of inflexible updates of the single-step temporal differential. More importantly, we use an independent policy to achieve autonomous avoidance and navigation of multiple UAVs without any communication with each other. In the case of communication rejection, the independent policy can achieve the consistency of multiple UAVs and avoid the greedy behavior of UAVs. In multiple-UAV dynamic destination scenarios, our work includes path planning, taking off from different initial positions, and dynamic path planning, taking off from the same initial position. The hardware-in-the-loop (HITL) experiment results show that our C51-Duel-IP algorithm is much more robust and effective than the original Dueling-IP and DQN-IP algorithms in an urban simulation environment. Our independent policy algorithm has similar effects as the shared policy but with the significant advantage of running in a communication denial environment.
Dynamical Behavior of a Cancer Growth Model with Chemotherapy and Boosting of the Immune System
Authors: Jawad Shireen , Winter Matthias , Rahman Zain-Aldeen S. A. , Al-Yasir Yasir I. A. , Zeb Anwar
Published: January 2023

In this study, we set up and analyze a cancer growth model that integrates a chemotherapy drug with the impact of vitamins in boosting and strengthening the immune system. The aim of this study is to determine the minimal amount of treatment required to eliminate cancer, which will help to reduce harm to patients. It is assumed that vitamins come from organic foods and beverages. The chemotherapy drug is added to delay and eliminate tumor cell growth and division. To that end, we suggest the tumor-immune model, composed of the interaction of tumor and immune cells, which is composed of two ordinary differential equations. The model’s fundamental mathematical properties, such as positivity, boundedness, and equilibrium existence, are examined. The equilibrium points’ asymptotic stability is analyzed using linear stability. Then, global stability and persistence are investigated using the Lyapunov strategy. The occurrence of bifurcations of the model, such as of trans-critical or Hopf type, is also explored. Numerical simulations are used to verify the theoretical analysis. The Runge–Kutta method of fourth order is used in the simulation of the model. The analytical study and simulation findings show that the immune system is boosted by regular vitamin consumption, inhibiting the growth of tumor cells. Further, the chemotherapy drug contributes to the control of tumor cell progression. Vitamin intake and chemotherapy are treated both individually and in combination, and in all situations, the minimal level required to eliminate the cancer is determined.
Locally Balanced G-Designs
Authors: Bonacini Paola , Gionfriddo Mario , Marino Lucia
Published: January 2023

Let G be a graph and let Kn be the complete graph of order n. A G-design is a decomposition of the set of edges of Kn in graphs isomorphic to G, which are called blocks. It is well-known that a G-design is balanced if all the vertices are contained in the number of blocks of G. In this paper, the definition of locally balanced G-design is given, generalizing the existing concepts related to balanced designs. Further, locally balanced G-designs are studied in the cases in which G≅C4+e and G≅C4+P3, determining the spectrum.
Does ESG Predict Systemic Banking Crises? A Computational Economics Model of Early Warning Systems with Interpretable Multi-Variable LSTM based on Mixture Attention
Authors: Lin Shu-Ling , Jin Xiao
Published: January 2023

Systemic banking crises can be very damaging to economic development, and environmental, social, and governance (ESG) can also damage national finances, but there is no research on whether ESG affects systemic banking crises, and we fill this gap. We first employ Fisher scores (FS) to select features and then use an interpretable multivariate long-short-term memory (IMV-LSTM) model with focal loss (FL) to account for class imbalance to model an early warning system (EWS) that can predict up to one year in advance. This study finds that ESG influences the occurrence of systemic banking crises, with our early warning system predicting each crisis a year in advance.
Dynamic Extraction of Initial Behavior for Evasive Malware Detection
Authors: Aboaoja Faitouri A. , Zainal Anazida , Ali Abdullah Marish , Ghaleb Fuad A. , Alsolami Fawaz Jaber , Rassam Murad A.
Published: January 2023

Recently, malware has become more abundant and complex as the Internet has become more widely used in daily services. Achieving satisfactory accuracy in malware detection is a challenging task since malicious software exhibit non-relevant features when they change the performed behaviors as a result of their awareness of the analysis environments. However, the existing solutions extract features from the entire collected data offered by malware during the run time. Accordingly, the actual malicious behaviors are hidden during the training, leading to a model trained using unrepresentative features. To this end, this study presents a feature extraction scheme based on the proposed dynamic initial evasion behaviors determination (DIEBD) technique to improve the performance of evasive malware detection. To effectively represent evasion behaviors, the collected behaviors are tracked by examining the entropy distributions of APIs-gram features using the box-whisker plot algorithm. A feature set suggested by the DIEBD-based feature extraction scheme is used to train machine learning algorithms to evaluate the proposed scheme. Our experiments’ outcomes on a dataset of benign and evasive malware samples show that the proposed scheme achieved an accuracy of 0.967, false positive rate of 0.040, and F1 of 0.975.
Asymptotic Properties of Random Restricted Partitions
Authors: Jiang Tiefeng , Wang Ke
Published: January 2023

We study two types of probability measures on the set of integer partitions of n with at most m parts. The first one chooses the partition with a chance related to its largest part only. We obtain the limiting distributions of all of the parts together and that of the largest part as n tending to infinity for m fixed or tending to infinity with m=o(n1/3). In particular, if m goes to infinity not too fast, the largest part satisfies the central limit theorem. The second measure is very general and includes the Dirichlet and uniform distributions as special cases. The joint asymptotic distributions of the parts are derived by taking limits of n and m in the same manner as that in the first probability measure.
Deep Learning-Based Malicious Smart Contract and Intrusion Detection System for IoT Environment
Authors: Shah Harshit , Shah Dhruvil , Jadav Nilesh Kumar , Gupta Rajesh , Tanwar Sudeep , Alfarraj Osama , Tolba Amr , Raboaca Maria Simona , Marina Verdes
Published: January 2023

The Internet of Things (IoT) is a key enabler technology that recently received significant attention from the scientific community across the globe. It helps transform everyone’s life by connecting physical and virtual devices with each other to offer staggering benefits, such as automation and control, higher productivity, real-time information access, and improved efficiency. However, IoT devices and their accumulated data are susceptible to various security threats and vulnerabilities, such as data integrity, denial-of-service, interception, and information disclosure attacks. In recent years, the IoT with blockchain technology has seen rapid growth, where smart contracts play an essential role in validating IoT data. However, these smart contracts can be vulnerable and degrade the performance of IoT applications. Hence, besides offering indispensable features to ease human lives, there is also a need to confront IoT environment security attacks, especially data integrity attacks. Toward this aim, this paper proposed an artificial intelligence-based system model with a dual objective. It first detects the malicious user trying to compromise the IoT environment using a binary classification problem. Further, blockchain technology is utilized to offer tamper-proof storage to store non-malicious IoT data. However, a malicious user can exploit the blockchain-based smart contract to deteriorate the performance IoT environment. For that, this paper utilizes deep learning algorithms to classify malicious and non-malicious smart contracts. The proposed system model offers an end-to-end security pipeline through which the IoT data are disseminated to the recipient. Lastly, the proposed system model is evaluated by considering different assessment measures that comprise the training accuracy, training loss, classification measures (precision, recall, and F1 score), and receiver operating characteristic (ROC) curve.
Halorotetin A: A Novel Terpenoid Compound Isolated from Ascidian Halocynthia rotetzi Exhibits the Inhibition Activity on Tumor Cell Proliferation
Authors: Li Jianhui , Han Shanhao , Zhu Yuting , Dong Bo
Published: January 2023

Halocynthia roretzi, the edible ascidian, has been demonstrated to be an important source of bioactive natural metabolites. Here, we reported a novel terpenoid compound named Halorotetin A that was isolated from tunic ethanol extract of H. roretzi by silica gel column chromatography, preparative layer chromatography (PLC), and semipreparative-HPLC. 1H and 13C NMRs, 1H-1H COSY, HSQC, HMBC, NOESY, and HRESIMS profiles revealed that Halorotetin A was a novel terpenoid compound with antitumor potentials. We therefore treated the culture cells with Halorotetin A and found that it significantly inhibited the proliferation of a series of tumor cells by exerting cytotoxicity, especially for the liver carcinoma cell line (HepG-2 cells). Further studies revealed that Halorotetin A affected the expression of several genes associated with the development of hepatocellular carcinoma (HCC), including oncogenes (c-myc and c-met) and HCC suppressor genes (TP53 and KEAP1). In addition, we compared the cytotoxicities of Halorotetin A and doxorubicin on HepG-2 cells. To our surprise, the cytotoxicities of Halorotetin A and doxorubicin on HepG-2 cells were similar at the same concentration and Halorotetin A did not significantly reduce the viability of the normal cells. Thus, our study identified a novel compound that significantly inhibited the proliferation of tumor cells, which provided the basis for the discovery of leading compounds for antitumor drugs.
Revision Total Knee Arthroplasty Utilizing Threaded Pins in Cement for Tibial Bone Loss
Authors: Jiganti Max , Tedesco Nicholas
Published: January 2023

Introduction: a primary goal in revision total knee arthroplasty is to recreate and restore near-normal knee biomechanics by reapproximating the native anatomy. Tibial bone loss poses a challenge for surgeons. Bone cement, bone allograft, screws-in-cement, metaphyseal sleeves or cones, and metallic augments are some options for addressing bony deficiency, with endoprosthetic proximal tibia replacement a consideration for the most severe cases. Case Description: we present a case for the novel use of threaded Steinmann pins augmented with cement to reconstruct a massive tibial metaphyseal cortical defect during revision knee arthroplasty. A 76-year-old male presented with an infected primary total knee arthroplasty using MSIS (Musculoskeletal Infection Society) criteria and underwent a standard two-stage revision total knee arthroplasty once the knee was confirmed sterile. Intraoperatively, significant posteromedial and metaphyseal tibial bone loss was identified. In order to avoid proximal tibial replacement and the extensor mechanism complications seen with these, coupled with obligate gastrocnemius flap, a metaphyseal cone was utilized in the proximal tibia with four vertical threaded Steinmann pins spaced approximately 1 cm apart at its periphery, subsequently cut flush with the level of the cone after cementation to recreate the tibial cortex. The patient’s function and range of motion continue to improve with no evidence of structural complication at 2.5 years of follow-up. Discussion: the implementation of threaded Steinmann pins was utilized in this case to stabilize a cemented metaphyseal cone in the revision of an infected total knee with significant tibial bone loss. The threaded property may help prevent migration of these pins in comparison to smooth pins. Creation of a stable platform in a revision total knee arthroplasty poses a substantial challenge in the context of significant bone loss, and our case depicts a good short-term outcome and another option for surgeons to consider before moving toward endoprostheses.
The GSTO2 (rs156697) Polymorphism Modifies Diabetic Nephropathy Risk
Authors: Pavlovic Dragana , Ristic Sinisa , Djukanovic Ljubica , Matic Marija , Kovacevic Marijana , Pljesa-Ercegovac Marija , Hadzi-Djokic Jovan , Savic-Radojevic Ana , Djukic Tatjana
Published: January 2023

Background and Objectives: In the development of type 2 diabetes mellitus (T2DM) and its complications, genetic and environmental factors play important roles. Diabetic nephropathy (DN), one of the major microangiopathic chronic diabetic complications, is associated with an increased risk of major cardiovascular events and all-cause mortality. The present study was designed to investigate the possible modifying effect of glutathione transferase polymorphisms (GSTM1, GSTT1, GSTP1 rs1138272/rs1695, GSTO1 rs4925 and GSTO2 rs156697) in the susceptibility to T2DM and diabetic nephropathy. Materials and Methods: GSTM1 and GSTT1 deletion polymorphisms were determined by multiplex PCR, whereas GSTO1, GSTO2, and GSTP1 polymorphisms were determined by the real-time PCR in 160 T2DM patients and 248 age- and gender-matched controls. Advanced glycation end products (AGEs) were measured by ELISA. Results: Among six investigated GST polymorphisms, a significant association between the GST genotypes and susceptibility for development of diabetes mellitus was found for the GSTM1, GSTT1, GSTP1 (rs1138272) and GSTO1 polymorphisms. When the GST genotypes’ distribution in diabetes patients was assessed in the subgroups with and without diabetic nephropathy, a significant association was found only for the GSTO2 rs156697 polymorphism. Diabetic patients, carriers of the GSTM1 null, GSTT1 null and variant GSTO1*AA genotypes, had significantly increased levels of AGEs in comparison with carriers of the GSTM1 active, GSTT1 active and referent GSTO1*CC genotypes (p < 0.001, p < 0.001, p = 0.004, respectively). Conclusions: The present study supports the hypothesis that GST polymorphisms modulate the risk of diabetes and diabetic nephropathy and influence the AGEs concentration, suggesting the potential regulatory role of these enzymes in redox homeostasis disturbances.
Design of an Antibiotic-Releasing Polymer: Physicochemical Characterization and Drug Release Patterns
Authors: Padinjarathil Himabindu , Mudradi Srikrishna , Balasubramanian Rajalakshmi , Drago Carmelo , Dattilo Sandro , Kothurkar Nikhil K. , Ramani Prasanna
Published: January 2023

Conventional drug delivery has its share of shortcomings, especially its rapid drug release with a relatively short duration of therapeutic drug concentrations, even in topical applications. Prolonged drug release can be effectively achieved by modifying the carrier in a drug delivery system. Among the several candidates for carriers studied over the years, poly (ether ether ketone), a biocompatible thermoplastic, was chosen as a suitable carrier. Its inherent hydrophobicity was overcome by controlled sulfonation, which introduced polar sulfonate groups onto the polymer backbone. Optimization of the sulfonation process was completed by the variation of the duration, temperature of the sulfonation, and concentration of sulfuric acid. The sulfonation was confirmed by EDS and the degree of sulfonation was determined by an NMR analysis (61.6% and 98.9%). Various physical properties such as morphology, mechanical strength, and thermal stability were studied using scanning electron microscopy, tensile testing, and thermogravimetric analysis. Cytotoxicity tests were performed on the SPEEK samples to study the variation in biocompatibility against a Vero cell line. The drug release kinetics of ciprofloxacin (CP) and nalidixic acid sodium salt (NA)-loaded membranes were studied in deionized water as well as SBF and compared against the absorbance of standardized solutions of the drug. The data were then used to determine the diffusion, distribution, and permeability coefficients. Various mathematical models were used to fit the obtained data to establish the order and mechanism of drug release. Studies revealed that drug release occurs by diffusion and follows zero-order kinetics.
Is It Possible to Prepare a “Super” Anion-Exchange Membrane by a Polypyrrole-Based Modification?
Authors: Kozmai Anton , Porozhnyy Mikhail , Ruleva Valentina , Gorobchenko Andrey , Pismenskaya Natalia , Nikonenko Victor
Published: January 2023

In spite of wide variety of commercial ion-exchange membranes, their characteristics, in particular, electrical conductivity and counterion permselectivity, are unsatisfactory for some applications, such as electrolyte solution concentration. This study is aimed at obtaining an anion-exchange membrane (AEM) of high performance in concentrated solutions. An AEM is prepared with a polypyrrole (PPy)-based modification of a heterogeneous AEM with quaternary ammonium functional groups. Concentration dependences of the conductivity, diffusion permeability and Cl− transport number in NaCl solutions are measured and simulated using a new version of the microheterogeneous model. The model describes changes in membrane swelling with increasing concentration and the effect of these changes on the transport characteristics. It is assumed that PPy occupies macro- and mesopores of the host membrane where it replaces non-selective electroneutral solution. Increasing conductivity and selectivity are explained by the presence of positively charged PPy groups. It is found that the conductivity of a freshly prepared membrane reaches 20 mS/cm and the chloride transport number > 0.99 in 4 M NaCl. A choice of input parameters allows quantitative agreement between the experimental and simulation results. However, PPy has shown itself to be an unstable material. This article discusses what parameters a membrane can have to show such exceptional characteristics.
Composite Proton-Conducting Membrane with Enhanced Phosphoric Acid Doping of Basic Films Radiochemically Grafted with Binary Vinyl Heterocyclic Monomer Mixtures
Authors: Sithambaranathan Paveswari , Nasef Mohamed Mahmoud , Ahmad Arshad , Abbasi Amin , Ting T. M.
Published: January 2023

A composite proton conducting membrane (PCM) was prepared by radiation-induced grafting (RIG) of binary mixtures of 4-vinyl pyridine (4-VP) and 1-vinylimidazole (1-VIm) onto poly(ethylene-co-tetrafluoroethylene) (ETFE) film followed by phosphoric acid (PA) doping. The grafting parameters such as absorbed dose, temperature, monomer concentration, time, and monomer ratio were varied to control the degree of grafting (DG%). The effect of the reactivity ratio of 4-VP and 1-VIm on the composition and degree of monomer unit alternation in the formed graft copolymer was investigated. The changes in the chemical and physical properties endowed by grafting and subsequent PA acid doping were monitored using analytical instruments. The mechanical properties and proton conductivity of the obtained membrane were evaluated and its performance was tested in H2/O2 fuel cell at 120 °C under anhydrous and partially wet conditions. The acid doping level was affected by the treatment parameters and enhanced by increasing DG. The proton conductivity was boosted by incorporating the combination of pyridine and imidazole rings originating from the formed basic graft copolymer of 4-VP/1-VIm dominated by 4-VP units in the structure. The proton conductivity showed a strong dependence on the temperature. The membrane demonstrated superior properties compared to its counterpart obtained by grafting 4-VP alone. The membrane also showed a strong potential for application in proton exchange membrane fuel cells (PEMFC) operating at 120 °C.
Recent Advancements in the Recovery and Reuse of Organic Solvents Using Novel Nanomaterial-Based Membranes for Renewable Energy Applications
Authors: Gupta Indrani , Gupta Oindrila
Published: January 2023

The energy crisis in the world is increasing rapidly owing to the shortage of fossil fuel reserves. Climate change and an increase in global warming necessitates a change in focus from petroleum-based fuels to renewable fuels such as biofuels. The remodeling of existing separation processes using various nanomaterials is of a growing interest to industrial separation methods. Recently, the design of membrane technologies has been the most focused research area concerning fermentation broth to enhance performance efficiency, while recovering those byproducts to be used as value added fuels. Specifically, the use of novel nano material membranes, which brings about a selective permeation of the byproducts, such as organic solvent, from the fermentation broth, positively affects the fermentation kinetics by eliminating the issue of product inhibition. In this review, which and how membrane-based technologies using novel materials can improve the separation performance of organic solvents is considered. In particular, technical approaches suggested in previous studies are discussed with the goal of emphasizing benefits and problems faced in order to direct research towards an optimized membrane separation performance for renewable fuel production on a commercial scale.
Flavonoid Production: Current Trends in Plant Metabolic Engineering and De Novo Microbial Production
Authors: Tariq Hasnat , Asif Saaim , Andleeb Anisa , Hano Christophe , Abbasi Bilal Haider
Published: January 2023

Flavonoids are secondary metabolites that represent a heterogeneous family of plant polyphenolic compounds. Recent research has determined that the health benefits of fruits and vegetables, as well as the therapeutic potential of medicinal plants, are based on the presence of various bioactive natural products, including a high proportion of flavonoids. With current trends in plant metabolite research, flavonoids have become the center of attention due to their significant bioactivity associated with anti-cancer, antioxidant, anti-inflammatory, and anti-microbial activities. However, the use of traditional approaches, widely associated with the production of flavonoids, including plant extraction and chemical synthesis, has not been able to establish a scalable route for large-scale production on an industrial level. The renovation of biosynthetic pathways in plants and industrially significant microbes using advanced genetic engineering tools offers substantial promise for the exploration and scalable production of flavonoids. Recently, the co-culture engineering approach has emerged to prevail over the constraints and limitations of the conventional monoculture approach by harnessing the power of two or more strains of engineered microbes to reconstruct the target biosynthetic pathway. In this review, current perspectives on the biosynthesis and metabolic engineering of flavonoids in plants have been summarized. Special emphasis is placed on the most recent developments in the microbial production of major classes of flavonoids. Finally, we describe the recent achievements in genetic engineering for the combinatorial biosynthesis of flavonoids by reconstructing synthesis pathways in microorganisms via a co-culture strategy to obtain high amounts of specific bioactive compounds
Fabrication of a Biomass-Derived Activated Carbon-Based Anode for High-Performance Li-Ion Batteries
Authors: Ahmed Faheem , Almutairi Ghazzai , Hasan Prince M. Z. , Rehman Sarish , Kumar Shalendra , Shaalan Nagih M. , Aljaafari Abdullah , Alshoaibi Adil , AlOtaibi Bandar , Khan Kaffayatullah
Published: January 2023

Porous carbons are highly attractive and demanding materials which could be prepared using biomass waste; thus, they are promising for enhanced electrochemical capacitive performance in capacitors and cycling efficiency in Li-ion batteries. Herein, biomass (rice husk)-derived activated carbon was synthesized via a facile chemical route and used as anode materials for Li-ion batteries. Various characterization techniques were used to study the structural and morphological properties of the prepared activated carbon. The prepared activated carbon possessed a carbon structure with a certain degree of amorphousness. The morphology of the activated carbon was of spherical shape with a particle size of ~40–90 nm. Raman studies revealed the characteristic peaks of carbon present in the prepared activated carbon. The electrochemical studies evaluated for the fabricated coin cell with the activated carbon anode showed that the cell delivered a discharge capacity of ~321 mAhg−1 at a current density of 100 mAg−1 for the first cycle, and maintained a capacity of ~253 mAhg−1 for 400 cycles. The capacity retention was found to be higher (~81%) with 92.3% coulombic efficiency even after 400 cycles, which showed excellent cyclic reversibility and stability compared to commercial activated carbon. These results allow the waste biomass-derived anode to overcome the problem of cyclic stability and capacity performance. This study provides an insight for the fabrication of anodes from the rice husk which can be redirected into creating valuable renewable energy storage devices in the future, and the product could be a socially and ethically acceptable product.
Insights into Alpine-Karst-Type Tufa Deposits in Geological Environmental Records: A Case Study of the Calcareous Tufa Profile of the Jiuzhaigou Natural Reserve on the Eastern Margin of the Tibetan Plateau
Authors: Lv Congcong , Zhao Xueqin , Jiang Yaoxi , Zhu Heyan , Zhang Hongmin , Wang Fudong , Li Qiongfang , Hou Keli
Published: January 2023

To study the geological environmental records of alpine-karst-type tufa deposits in the eastern margin of the Tibetan Plateau, the calcareous tufa profile exposed by the “8.8” Jiuzhaigou earthquake was taken as the research object and combined with a field geological investigation. Further, the petrography, sedimentology, chronology, and elemental geochemistry of the calcareous tufa were studied and analyzed. The results show the following. (1) The Sparkling Lake calcareous tufa profile was deposited under the background of a warm and humid climate during the Holocene. The growth pattern follows a bottom-to-top deposition. (2) At 750 ± 30–300 ± 30 aB.P., the calcareous tufa layers were gray-black as a whole, and the changes in mineral composition and elemental geochemistry indicate a fluctuating upward trend for temperature and precipitation during this period. (3) The formation of two sets of black peat layers in the upper part of the tufa calcareous profile is due to the synergistic action of multiple factors caused by strong tectonic activity. In conclusion, the deposition mechanism of the calcareous tufa in Jiuzhaigou was controlled by paleoclimate hydrology and glaciation for a long time, while strong tectonic activity over a short period of time considerably changed the color, structure, element content, and mineral composition of the calcareous tufa.
Advances in Low Pt Loading Membrane Electrode Assembly for Proton Exchange Membrane Fuel Cells
Authors: Cao Feng , Ding Rui , Rui Zhiyan , Wang Xuebin , Meng Zhen , Zhang Bin , Dong Weiwen , Li Jia , Liu Jianguo , Jiang Xiangfen
Published: January 2023

Hydrogen has the potential to be one of the solutions that can address environmental pollution and greenhouse emissions from traditional fossil fuels. However, high costs hinder its large-scale commercialization, particularly for enabling devices such as proton exchange membrane fuel cells (PEMFCs). The precious metal Pt is indispensable in boosting the oxygen reduction reaction (ORR) in cathode electrocatalysts from the most crucial component, i.e., the membrane electrode assembly (MEA). MEAs account for a considerable amount of the entire cost of PEMFCs. To address these bottlenecks, researchers either increase Pt utilization efficiency or produce MEAs with enhanced performance but less Pt. Only a few reviews that explain the approaches are available. This review summarizes advances in designing nanocatalysts and optimizing the catalyst layer structure to achieve low-Pt loading MEAs. Different strategies and their corresponding effectiveness, e.g., performance in half-cells or MEA, are summarized and compared. Finally, future directions are discussed and proposed, aiming at affordable, highly active, and durable PEMFCs.
Development of Quantitative Chemical Ionization Using Gas Chromatography/Mass Spectrometry and Gas Chromatography/Tandem Mass Spectrometry for Ambient Nitro- and Oxy-PAHs and Its Applications
Authors: Jo Jungmin , Lee Ji-Yi , Jang Kyoung-Soon , Matsuki Atsushi , Natsagdorj Amgalan , Ahn Yun-Gyong
Published: January 2023

The concentration of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere has been continually monitored since their toxicity became known, whereas nitro-PAHs (NPAHs) and oxy-PAHs (OPAHs), which are derivatives of PAHs by primary emissions or secondary formations in the atmosphere, have gained attention more recently. In this study, a method for the quantification of 18 NPAH and OPAH congeners in the atmosphere based on combined applications of gas chromatography coupled with chemical ionization mass spectrometry is presented. A high sensitivity and selectivity for the quantification of individual NPAH and OPAH congeners without sample preparations from the extract of aerosol samples were achieved using negative chemical ionization (NCI/MS) or positive chemical ionization tandem mass spectrometry (PCI-MS/MS). This analytical method was validated and applied to the aerosol samples collected from three regions in Northeast Asia—namely, Noto, Seoul, and Ulaanbaatar—from 15 December 2020 to 17 January 2021. The ranges of the method detection limits (MDLs) of the NPAHs and OPAHs for the analytical method were from 0.272 to 3.494 pg/m3 and 0.977 to 13.345 pg/m3, respectively. Among the three regions, Ulaanbaatar had the highest total mean concentration of NPAHs and OPAHs at 313.803 ± 176.349 ng/m3. The contribution of individual NPAHs and OPAHs in the total concentration differed according to the regional emission characteristics. As a result of the aerosol samples when the developed method was applied, the concentrations of NPAHs and OPAHs were quantified in the ranges of 0.016~3.659 ng/m3 and 0.002~201.704 ng/m3, respectively. It was concluded that the method could be utilized for the quantification of NPAHs and OPAHs over a wide concentration range.
Evaluation of Free Online ADMET Tools for Academic or Small Biotech Environments
Authors: Dulsat Júlia , López-Nieto Blanca , Estrada-Tejedor Roger , Borrell José I.
Published: January 2023

For a new molecular entity (NME) to become a drug, it is not only essential to have the right biological activity also be safe and efficient, but it is also required to have a favorable pharmacokinetic profile including toxicity (ADMET). Consequently, there is a need to predict, during the early stages of development, the ADMET properties to increase the success rate of compounds reaching the lead optimization process. Since Lipinski’s rule of five, the prediction of pharmacokinetic parameters has evolved towards the current in silico tools based on empirical approaches or molecular modeling. The commercial specialized software for performing such predictions, which is usually costly, is, in many cases, not among the possibilities for research laboratories in academia or at small biotech companies. Nevertheless, in recent years, many free online tools have become available, allowing, more or less accurately, for the prediction of the most relevant pharmacokinetic parameters. This paper studies 18 free web servers capable of predicting ADMET properties and analyzed their advantages and disadvantages, their model-based calculations, and their degree of accuracy by considering the experimental data reported for a set of 24 FDA-approved tyrosine kinase inhibitors (TKIs) as a model of a research project.
Design and Synthesis of Novel Helix Mimetics Based on the Covalent H-Bond Replacement and Amide Surrogate
Authors: Liu Junyang , Tang Shoubin , Yan Jia-Lei , Ye Tao
Published: January 2023

A novel hydrogen bond surrogate-based (HBS) α-helix mimetic was designed by the combination of covalent H-bond replacement and the use of an ether linkage to substitute an amide bond within a short peptide sequence. The new helix template could be placed in position other than the N-terminus of a short peptide, and the CD studies demonstrate that the template adopts stable conformations in aqueous buffer at exceptionally high temperatures.
Fuel Characteristics and Removal of AAEMs in Hydrochars Derived from Sewage Sludge and Corn Straw
Authors: Guo Shuai , Xiao Weinan , Liu Zhaoyuan , Zhao Deng , Chen Kaixin , Zhao Chenchen , Li Xingcan , Li Guangyu
Published: January 2023

Co-hydrothermal carbonization (Co-HTC) of sewage sludge (SS) and corn straw (CS) for fuel preparation is a waste treatment method that reduces the pre-treatment cost of solid waste and biomass fuel. Based on the response surface methodology (RSM), a test was designed to prepare SS and CS hydrochars using a hydrothermal high-pressure reactor. The test examined the higher heating value (HHV) and the concentrations of alkali metals and alkaline earth metals (AAEMs) and Cl. The HHV of SS-hydrochar decreased with an increase in reaction temperature, but that of CS-hydrochar increased. The yield of CS-hydrochar was at 26.74–61.26%, substantially lower than that of SS-hydrochar. Co-hydrochar has the advantages of HHV and an acceptable yield. The HHV of co-hydrochar was 9215.51–12,083.2 kJ/kg, representing an increase of 12.6–47.6% over single component hydrochar, while the yield of co-hydrochar was 41.46–72.81%. In addition, the stabilities of AAEM and Cl in the co-hydrochar were Mg > Ca > K > Na > Cl. SS and CS had a synergistic effect on dechlorination efficiency (DE), which had a negative effect on the removal efficiency (RE) of Ca and Na. The optimal hydrocharization conditions were a temperature of approximately 246.14 °C, a residence time of approximately 90 min, and a mixing ratio of SS–CS of approximately 57.18%. The results offer a way to utilize SS and CS by Co-HTC and convert them into low-chlorine and low-alkali fuel, thus pushing the improvement of this promising waste-to-energy technology.
In Silico Mining of Natural Products Atlas (NPAtlas) Database for Identifying Effective Bcl-2 Inhibitors: Molecular Docking, Molecular Dynamics, and Pharmacokinetics Characteristics
Authors: Almansour Nahlah Makki , Allemailem Khaled S. , Abd El Aty Abeer Abas , Ismail Ekram Ismail Fagiree , Ibrahim Mahmoud A. A.
Published: January 2023

The Bcl-2 protein has a vital function in controlling the programmed cell doom of mitochondria. If programmed cell death signals are obstructed, an imbalance between cell survival and death will occur, which is a significant reason for cancer. Therefore, the Bcl-2 protein was identified as a possible therapeutic target for carcinoma treatment. Herein, the Natural Products Atlas (NPAtlas) compounds were virtually screened, seeking potent inhibitors towards the Bcl-2 protein. The performance of AutoDock Vina software to predict the docking score and pose of the investigated compounds was first validated according to the available experimental data. Based on the validated AutoDock Vina parameters, the NPAtlas database was filtered against the Bcl-2 protein. The natural compounds with docking scores less than that of the venetoclax (calc. −10.6 kcal/mol) were submitted to MD simulations, followed by MM-GBSA binding energy calculations. According to MM-GBSA//200 ns MD simulations, saquayamycin F (NPA002200) demonstrated promising binding affinity with a ΔGbinding value of −53.9 kcal/mol towards the Bcl-2 protein when compared to venetoclax (ΔGbinding = −50.6 kcal/mol). The energetical and structural analyses showed a great constancy of the saquayamycin F inside the Bcl-2 protein active site. Moreover, the ADMET and drug-likeness features of the saquayamycin F were anticipated, indicating its good oral bioavailability. According to in silico computations, saquayamycin F is proposed to be used as a therapeutic agent against the wild-type Bcl-2 protein and warrants further experimental assays.
Adsorption Capacity and Desorption Efficiency of Activated Carbon for Odors from Medical Waste
Authors: Park Jung Eun , Jo Eun Seo , Lee Gi Bbum , Lee Sang Eun , Hong Bum-Ui
Published: January 2023

Five types of odor-emitting exhaust gases from medical waste were selected, and their adsorption capacity and desorption efficiency were investigated using activated carbon. The selected gases included polar gases (hydrogen sulfide (H2S) and ammonia (NH3)) and non-polar gases (acetaldehyde (AA), methyl mercaptan (MM), and trimethylamine (TMA))). Commercial activated carbon with a specific surface area of 2276 m2/g was used as the adsorbent. For the removal of odor from medical waste, we investigated: (1) the effective adsorption capacity of a single gas (<1 ppm), (2) the effect of the adsorbed NH3 gas concentration and flow rate, and (3) the desorption rate using NH3 gas. The values of the effective adsorption capacity of the single gas were in the following order: H2S < NH3 < AA < MM < TMA, at 0.2, 4.2, 6.3, 6.6, and 35.7 mg/g, respectively. The results indicate that polar gases have a lower effective adsorption capacity than that of non-polar gases, and that the size of the gas molecules and effective adsorption capacity exhibit a proportional relationship. The effective adsorption performance of NH3 gas showed an increasing trend with NH3 concentration. Therefore, securing optimal conditions for adsorption/desorption is imperative for the highly efficient removal of odor from medical waste.
Mucilage from Yellow Pitahaya (Selenicereus megalanthus) Fruit Peel: Extraction, Proximal Analysis, and Molecular Characterization
Authors: Otálora María Carolina , Wilches-Torres Andrea , Gómez Castaño Jovanny A.
Published: January 2023

Mucilage is a hydrophilic biopolymeric material of interest in the food industry due to its high content of dietary fiber, antioxidant activity, and gelling and thickening capacities, which is present in high concentration in agricultural by-products, such as the peel of cacti fruits. In this work, the powdered mucilage extracted from the peel of yellow pitahaya (Selenicereus megalanthus) fruit was characterized using a multi-technical approach that included proximal analysis (proteins, lipids, crude fiber, ash, and carbohydrates), as well as structural (FTIR, NMR, UPLC-QTOF-MS, and X-ray diffraction), colorimetric (CIELab parameters), morphological (SEM), and thermal (DSC/TGA) methods. Likewise, its total content of dietary fiber and polyphenols, as well as its antioxidant activity, were determined. This dried mucilage presented a light pale yellow-reddish color, attributed to the presence of betalains (bioactive pigments with high antioxidant activity). The FTIR spectrum revealed functional groups associated with a low presence of proteins (5.45 ± 0.04%) and a high concentration of oligosaccharides (55.26 ± 0.10%). A zeta potential of −29.90 ± 0.90 mV was determined, denoting an anionic nature that favors the use of this mucilage as a stable colloidal dispersion. UPLC-QTOF-MS analysis revealed a major oligosaccharide composition based on galacturonic acid units in anionic form. SEM micrographs revealed a cracked morphology composed of amorphous and irregular particles. According to the DSC/TGA results, this mucilage can be introduced as a new source of hydrocolloids in food processes since it has high thermal stability that has been manifested up to 373.87 °C. In addition, this biopolymer exhibited a high content of polyphenols (25.00 ± 0.01-g gallic acid equivalent (GAE)/100-g sample), dietary fiber (70.51%), and antioxidant activity (1.57 ± 0.01 mmol Trolox equivalents/kg of sample). It was concluded that this mucilaginous material presents sufficient physicochemical and functional conditions to be used as a nutritional ingredient, thus giving valorization to this agricultural by-product.
Metal-Free One-Pot Multi-Functionalization of Unsaturated Compounds with Interelement Compounds by Radical Process
Authors: Yamamoto Yuki , Ogawa Akiya
Published: January 2023

In recent years, the importance of “environmentally friendly manufacturing” has been increasing toward the establishment of a resource-recycling society. In organic synthesis, as well, it is becoming increasingly important to develop new synthetic strategies with resource conservation and the recycling of elemental resources in mind, rather than just only synthesis. Many studies on the construction of frameworks of functional molecules using ionic reactions and transition-metal-catalyzed reactions have been reported, but most of them have focused on the formation of carbon–carbon bonds. However, it is essential to introduce appropriate functional groups at appropriate positions in molecules in order for the molecules to express their functions, and furthermore, the highly selective preparation of multiple functional groups is considered important for the creation of new functional molecules. In this review, we focus on radical reactions with high functional group selectivity and overview the recent progress in practical methods for the simultaneous introduction of multiple functional groups and propose future synthetic strategies that emphasize the recycling of elemental resources and environmental friendliness.
Hepatoprotective Effects of Rosmarinic Acid on Ovalbumin-Induced Intestinal Food Allergy Mouse Model
Authors: Jia Binmei , Shang Jieli , Zeng Haolong , Wang Xuanpei , Fang Min , Xu Lin , Liu Xin , Wu Kejia , Gong Zhiyong , Yang Qing
Published: January 2023

Rosmarinic acid (RA) has been proven to exert antianaphylaxis in atopic dermatitis, asthma, and allergic rhinitis. The aim of this study was to determine the hepatoprotective effects of RA on ovalbumin (OVA) challenge-induced intestinal allergy. The results exhibited that RA could relieve anaphylactic symptoms, decrease diarrhea, and prevent hypothermia in allergic mice. Moreover, the elevation of OVA specific IgE (OVA-sIgE), histamine, and mouse mast cell proteinases (mMCP-1) in the serum of OVA challenged mice were remarkably inhibited by RA. OVA challenge resulted in notable increases in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) activities, liver malondialdehyde (MDA) and nitic oxide (NO) levels, and a remarkable decrease in liver superoxide dismutase (SOD) activity and glutathione (GSH) level. RA treatments succeeded in improving these biochemical parameters and promote the redox homeostasis. Cytokine expression evaluation showed that RA effectively enhanced the expression of anti-inflammatory cytokines (IL-10 and FOXP-3) in the liver of OVA-challenged mice. Meanwhile, the elevation of pro-inflammatory cytokines (TNF-α, IL-4, IL-6, mMCP-1, and iNOS) were remarkably inhibited by RA. These findings suggest that RA possesses hepatoprotective effects on OVA challenge-induced liver injury. The anti-oxidative and anti-inflammatory activities of RA potentially play vital roles in this process.
Identification of 3-Methoxyphenylacetic Acid as a Phytotoxin, Produced by Rhizoctonia solani AG-3 TB
Authors: Li Xinchun , Hou HuiHui , Liu He , Wang Hancheng , Cai Liuti , An Mengnan , Zhang Chong , Wu Yuanhua
Published: January 2023

Tobacco target spot disease is caused by Rhizoctonia solani AG-3 TB, which causes serious harm to the quality and yield of tobacco. In this study, thin layer chromatography (TLC), high performance liquid chromatography (HPLC), infrared absorption spectroscopy (IR), and nuclear magnetic resonance spectroscopy (NMR) were used to purify and identify the potential phytotoxin produced by R. solani AG-3 TB. The result indicated that the purified toxin compound was 3-methoxyphenylacetic acid (3-MOPAA) (molecular formula: C9H10O3). The exogenous purified compound 3-MOPAA was tested, and the results revealed that 3-MOPAA can cause necrosis in tobacco leaves. 3-MOPAA is a derivative of phenylacetic acid (PAA), which should be produced by specific enzymes, such as hydroxylase or methylase, in the presence of PAA. These results enrich the research on the pathogenic phytotoxins of R. solani and provide valuable insights into the pathogenic mechanism of AG-3 TB.