bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibitory Effects of Bacterial Silk-like Biopolymer on Herpes Simplex Virus Type 1, Adenovirus Type 7 and Hepatitis C Virus Infection
Authors: El-Fakharany Esmail M. , Abu-Serie Marwa M. , Habashy Noha H. , El-Deeb Nehal M. , Abu-Elreesh Gadallah M. , Zaki Sahar , Abd-EL-Haleem Desouky
Published: February 2022

Bacterial polymeric silk is produced by Bacillus sp. strain NE and is composed of two proteins, called fibroin and sericin, with several biomedical and biotechnological applications. In the current study and for the first time, the whole bacterial silk proteins were found capable of exerting antiviral effects against herpes simplex virus type-1 (HSV-1), adenovirus type 7 (AD7), and hepatitis C virus (HCV). The direct interaction between bacterial silk-like proteins and both HSV-1 and AD7 showed potent inhibitory activity against viral entry with IC50 values determined to be 4.1 and 46.4 μg/mL of protein, respectively. The adsorption inhibitory activity of the bacterial silk proteins showed a blocking activity against HSV-1 and AD7 with IC50 values determined to be 12.5 and 222.4 ± 1.0 μg/mL, respectively. However, the bacterial silk proteins exhibited an inhibitory effect on HSV-1 and AD7 replication inside infected cells with IC50 values of 9.8 and 109.3 μg/mL, respectively. All these results were confirmed by the ability of the bacterial silk proteins to inhibit viral polymerases of HSV-1 and AD7 with IC50 values of 164.1 and 11.8 μg/mL, respectively. Similarly, the inhibitory effect on HCV replication in peripheral blood monocytes (PBMCs) was determined to be 66.2% at concentrations of 100 μg/mL of the bacterial silk proteins. This antiviral activity against HCV was confirmed by the ability of the bacterial silk proteins to reduce the ROS generation inside the infected cells to be 50.6% instead of 87.9% inside untreated cells. The unique characteristics of the bacterial silk proteins such as production in large quantities via large-scale biofermenters, low costs of production, and sustainability of bacterial source offer insight into its use as a promising agent in fighting viral infection and combating viral outbreaks.
A Novel Integrated Biomarker for Evaluation of Risk and Severity of Coronary Atherosclerosis, and Its Validation
Authors: Metelskaya Victoria , Gavrilova Natalia , Zhatkina Maria , Yarovaya Elena , Drapkina Oxana
Published: February 2022

Objective: To assess the feasibility of a combination of biochemical and imaging parameters for estimation of risk and severity of coronary atherosclerosis (CA), and to verify the created integrated biomarker (i-BIO) on independent cohort. Methods: Two cohorts of patients admitted to the hospital for coronary angiography and ultrasound carotid dopplerography were enrolled into the study (n = 205 and n = 216, respectively). The extent of CA was assessed by Gensini Score (GS). Results: According to GS, participants were distributed as follows: atherosclerosis-free (GS = 0), CA of any stage (GS > 0), subclinical CA (GS < 35), severe CA (GS ≥ 35). Based on the analysis of mathematical models, including biochemical and imaging parameters, we selected and combined the most significant variables as i-BIO. The ability of i-BIO to detect the presence and severity of CA was estimated using ROC-analysis with cut-off points determination. Risk of any CA (GS > 0) at i-BIO > 4 was 7.3 times higher than in those with i-BIO ≤ 4; risk of severe CA (GS ≥ 35) at i-BIO ≥ 9 was 3.1 times higher than at i-BIO < 9. Results on the tested cohort confirmed these findings. Conclusions: The i-BIO > 4 detected CA (GS > 0) with sensitivity of 87.9%, i-BIO ≥ 9 excluded patients without severe CA (GS < 35), specificity 79.8%. Validation of i-BIO confirmed the feasibility of i-BIO > 4 to separate patients with any CA with sensitivity 76.2%, and of i-BIO ≥ 9 to exclude atherosclerosis-free subjects with specificity of 84.0%.
Effects of Low Temperatures on Flexural Strength of Macro-Synthetic Fiber Reinforced Concrete: Experimental and Numerical Investigation
Authors: Aidarov Stanislav , Nogales Alejandro , Reynvart Igor , Tošić Nikola , de la Fuente Albert
Published: February 2022

Fiber-reinforced concrete (FRC) is an attractive alternative to traditional steel bar-reinforced concrete structures, as evidenced by the constantly increasing market consumption of structural fibers for this purpose. In spite of significant research dedicated to FRC, less attention has been given to the effects of low temperatures on the mechanical properties of FRC, which can be critical for a variety of structural typologies and regions. With this in mind, an experimental program was carried out to assess the flexural behavior of macro-synthetic fiber-reinforced concrete (MSFRC) at different temperatures (from 20 °C to −30 °C) by means of three-point bending notched beam tests. The tested MSFRCs were produced by varying the content of polypropylene fibers (4 and 8 kg/m3). The results proved that the flexural strength capacity of all MSFRCs improved with decreasing temperature. Finite element analyses were then used to calibrate constitutive models following fib Model Code 2010 guidelines and to formulate empirical adjustments for taking into account the effects of low temperatures. The outcomes of this research are the basis for future experimental and numerical efforts meant to improve the design of MSFRCs subjected to low temperatures during service conditions.
Tin Diselenide (SnSe2) Van der Waals Semiconductor: Surface Chemical Reactivity, Ambient Stability, Chemical and Optical Sensors
Authors: D'Olimpio Gianluca , Farias Daniel , Kuo Chia-Nung , Ottaviano Luca , Lue Chin Shan , Boukhvalov Danil W. , Politano Antonio
Published: February 2022

Tin diselenide (SnSe2) is a layered semiconductor with broad application capabilities in the fields of energy storage, photocatalysis, and photodetection. Here, we correlate the physicochemical properties of this van der Waals semiconductor to sensing applications for detecting chemical species (chemosensors) and millimeter waves (terahertz photodetectors) by combining experiments of high-resolution electron energy loss spectroscopy and X-ray photoelectron spectroscopy with density functional theory. The response of the pristine, defective, and oxidized SnSe2 surface towards H2, H2O, H2S, NH3, and NO2 analytes was investigated. Furthermore, the effects of the thickness were assessed for monolayer, bilayer, and bulk samples of SnSe2. The formation of a sub-nanometric SnO2 skin over the SnSe2 surface (self-assembled SnO2/SnSe2 heterostructure) corresponds to a strong adsorption of all analytes. The formation of non-covalent bonds between SnO2 and analytes corresponds to an increase of the magnitude of the transferred charge. The theoretical model nicely fits experimental data on gas response to analytes, validating the SnO2/SnSe2 heterostructure as a suitable playground for sensing of noxious gases, with sensitivities of 0.43, 2.13, 0.11, 1.06 [ppm]−1 for H2, H2S, NH3, and NO2, respectively. The corresponding limit of detection is 5 ppm, 10 ppb, 250 ppb, and 400 ppb for H2, H2S, NH3, and NO2, respectively. Furthermore, SnSe2-based sensors are also suitable for fast large-area imaging applications at room temperature for millimeter waves in the THz range.
Characterization of Five Collagenous Biomaterials by SEM Observations, TG-DTA, Collagenase Dissolution Tests and Subcutaneous Implantation Tests
Authors: Hoshi Miki , Sawada Tomofumi , Hatakeyama Wataru , Taira Masayuki , Hachinohe Yuki , Takafuji Kyoko , Kihara Hidemichi , Takemoto Shinji , Kondo Hisatomo
Published: February 2022

Collagenous biomaterials that are clinically applied in dentistry have dermis-type and membrane-type, both of which are materials for promoting bone and soft tissue formation. The properties of materials supplied with different types could affect their biodegradation periods. The purpose of this study was to characterize five of these products by four different methods: scanning electron microscopy (SEM) observation, thermogravimetry-differential thermal analysis (TG-DTA), 0.01 wt% collagenase dissolution test, and subcutaneous implantation test in vivo. SEM micrographs revealed that both dermis and membranous materials were fibrous and porous. The membranous materials had higher specific derivative thermal gravimetry (DTG) peak temperatures in TG-DTA at around 320 °C, longer collagenase dissolution time ranging from about 300 to 500 min, and more longevity in mice exceeding 9 weeks than the dermis materials. There existed a correlation between the peak temperature in TG-DTA and the collagenase dissolution time. It was considered that higher cross-link degree among collagen fibrils of the membrane-type collagenous materials might account for these phenomena. The experimental protocol and numerical results obtained could be helpful for selection and future development of fibrous collagenous biomaterials in clinical use.
Flocculation of Clay-Based Tailings: Differences of Kaolin and Sodium Montmorillonite in Salt Medium
Authors: Nieto Steven , Toro Norman , Robles Pedro , Gálvez Edelmira , Gallegos Sandra , Jeldres Ricardo I.
Published: February 2022

Complex gangues and low-quality waters are a concern for the mining industries, particularly in water shortage areas, where the closure of hydric circuits and reduction in water use are essential to maintain the economic and environmental sustainability of mineral processing. This study analyzes the phenomena involved in the water recovery stage, such as sedimentation of clay-based tailings flocculated with anionic polyelectrolyte in industrial water and seawater. Flocculation–sedimentation batch tests were performed to ascertain the aggregate size distribution, the hindered settling rate, and the structure of flocs expressed through their fractal dimension and density. The aggregates’ properties were characterized by the Focused Beam Reflectance Measurement (FBRM) and Particle Vision Microscope (PVM) techniques. The impact of the type of water depends on the type of clay that constitutes the suspension. For quartz/kaolin, the highest performance was obtained in industrial water, with bigger aggregates and faster settling rates. However, the tailings composed of quartz/Na-montmorillonite reversed this trend. The type of water impacted the efficiency of primary-particle aggregation. The trials in industrial water generated a portion of non-flocculated particles, which was observed through a bimodal distribution in the unweighted chord-length distribution. This behavior was not observed in seawater, where a perceptible fraction of non-flocculated particles was not found. The additional cationic bonds that offer seawater favor finer primary-particle agglomeration for all tailings types.
Smart Materials Prediction: Applying Machine Learning to Lithium Solid-State Electrolyte
Authors: Hu Qianyu , Chen Kunfeng , Liu Fei , Zhao Mengying , Liang Feng , Xue Dongfeng
Published: February 2022

Traditionally, the discovery of new materials has often depended on scholars’ computational and experimental experience. The traditional trial-and-error methods require many resources and computing time. Due to new materials’ properties becoming more complex, it is difficult to predict and identify new materials only by general knowledge and experience. Material prediction tools based on machine learning (ML) have been successfully applied to various materials fields; they are beneficial for modeling and accelerating the prediction process for materials that cannot be accurately predicted. However, the obstacles of disciplinary span led to many scholars in materials not having complete knowledge of data-driven materials science methods. This paper provides an overview of the general process of ML applied to materials prediction and uses solid-state electrolytes (SSE) as an example. Recent approaches and specific applications to ML in the materials field and the requirements for building ML models for predicting lithium SSE are reviewed. Finally, some current obstacles to applying ML in materials prediction and prospects are described with the expectation that more materials scholars will be aware of the application of ML in materials prediction.
Rotating Directional Solidification of Ternary Eutectic Microstructures in Bi-In-Sn: A Phase-Field Study
Authors: Dargahi Noubary Kaveh Dargahi , Kellner Michael , Nestler Britta
Published: February 2022

For the first time, the experimental processing condition of a rotating directional solidification is simulated in this work, by means of a grand-potential-based phase-field model. To simulate the rotating directional solidification, a new simulation setup with a rotating temperature field is introduced. The newly developed configuration can be beneficent for a more precise study of the ongoing adjustment mechanisms during temperature gradient controlled solidification processes. Ad hoc, the solidification of the ternary eutectic system Bi-In-Sn with three distinct solid phases α,β,δ is studied in this paper. For this system, accurate in situ observations of both directional and rotating directional solidification experiments exist, which makes the system favorable for the investigation. The two-dimensional simulation studies are performed for both solidification processes, considering the reported 2D patterns in the steady state growth of the bulk samples. The desired αβαδ phase ordering repeat unit is obtained within both simulation types. By considering anisotropy of the interfacial energies, experimentally reported tilted lamellae with respect to normal vectors of the solidification front, as well as predominant role of αβ anisotropy in tilting phenomenon, are observed. The results are validated by using the Jackson–Hunt analysis and by comparing with the existing experimental data. The convincing agreements indicate the applicability of the introduced method.
Maleic Anhydride Polylactic Acid Coupling Agent Prepared from Solvent Reaction: Synthesis, Characterization and Composite Performance
Authors: Oliver-Ortega Helena , Reixach Rafel , Espinach Francesc Xavier , Méndez José Alberto
Published: February 2022

In the present work, a functionalization of polylactic acid (PLA) has been carried out to anchor maleic anhydride onto the main polymer chain to promote improvement in the compatibility of this polymer matrix with cellulose fibres. Low-molecular-weight PLA has been reacted with maleic anhydride following different procedures: a bulk reaction in an internal mixer and a solution reaction. The presence of oxygen during bulk processing did not allow for functionalization, guiding the reaction towards a decrease in the molecular weight of the material. On the contrary, a controlled reaction under an inert atmosphere in the presence of dioxane as the solvent, at reflux temperature, led to the functionalization of the polymer reaching different yields depending on the percentage of radical initiator and maleic anhydride added and reaction time. The yield of functionalization has been monitored by acid number titration as well as 1H NMR, with optimal yield values of functionalization being up to 3.5%. The PLA-functionalized formula has been used to make commercial PLA compatible with cellulose fibres derived from a thermomechanical treatment. The addition of 10% w/w of fibres to PLA increases the ultimate tensile strength (UTS) of PLA by up to 15%. The incorporation of 4 w/w of the already-functionalized coupling agent to the composite produces improvements in UTS of up to 24% regarding PLA, which confirms the functionalization from a performance point of view.
TEM Microstructure, Mechanical Properties and Temperature Estimation in the 5XXX Series Al-Mg-Si Aluminum Alloy with W-Ni-Fe Tungsten Composite Friction-Welded Joints
Authors: Winiczenko Radosław , Kaczorowski Mieczysław , Krzyńska Anna , Goroch Olgierd , Skibicki Andrzej , Skoczylas Paweł
Published: February 2022

The temperature distributions, microstructure, and mechanical properties of tungsten composite with aluminum alloy friction-welded joints are presented in this paper. The effects of welding parameters on flash diameter, shortening, joint efficiency, microhardness, and microstructure were studied. Empirical temperature models for heating and cooling phases are proposed in this study. The predicted maximum temperatures at the periphery and in the axis of aluminum specimens were close to 550 °C and 480 °C at the interface, respectively. Moreover, the peak temperature in the weld zone was studied analytically. A maximum tensile strength of 234 MPa was reached for the following welding parameters: friction time of 3.5 s and friction force of 12.5 kN. The efficiency of the welded samples decreased after reaching the maximum value, with an increase of friction time and force. Maximum hardness at the interface and the half-radius reached 100 HV and 80 HV in the aluminum alloy joints, respectively. Dynamic recrystallisation areas on the aluminum alloy side were observed. Transmission electron microscopy observations of the microstructure in the aluminum alloy revealed the presence of a high dislocation density compared to the parent material.
Investigation of an Impedimetric LaSrMnO3-Au/Y2O3-ZrO2-Al2O3 Composite NOx Sensor
Authors: Pal Nabamita , Dutta Gaurab , Kharashi Khawlah , Murray Erica
Published: February 2022

Composite NOx sensors were fabricated by combining partially and fully stabilized yttria-doped zirconia with alumina forming a composite electrolyte, Y2O3-ZrO2-Al2O3, and strontium-doped lanthanum manganese oxide mixed with gold to form the composite sensing electrode, La0.8 Sr0.2MnO3-Au. A surface chemistry analysis of the composite sensor was conducted to interpret defects and the structural phases present at the Y2O3-ZrO2-Al2O3 electrolyte, as well as the charge conduction mechanism at the LaSrMnO3-Au electrode surface. Based on the surface chemistry analysis, ionic and electronic transport properties, and microstructural features of sensor components, the working principle was described for NOx sensing at the composite sensor. The role of the composite materials on the NOx sensing response, cross-sensitivity to O2, H2O, CO, CO2, and CH4, and the response/recovery rates relative to sensor accuracy were characterized by operating the composite NOx sensors via the impedimetric method. The composite sensors were operated at temperatures ranging from 575 to 675 °C in dry and humidified gas environments with NO and NO2 concentrations varying from 0 to 100 ppm, where the balance gas was N2. It was found that the microstructure of the composite NOx sensor electrolyte and sensing electrode had a significant effect on interfacial reactions at the triple phase boundary, as well as the density of active sites for oxygen reactions. Overall, the composite NOx sensor microstructure enabled a high NOx sensing response, along with low cross-sensitivity to O2, CO, CO2, and CH4, and promoted NO detection down to 2 ppm.
The Use of a High-Pressure Water-Ice Jet for Removing Worn Paint Coating in Renovation Process
Authors: Chomka Grzegorz , Chodór Jarosław , Kukiełka Leon , Kasperowicz Maciej
Published: February 2022

The paper presents the results of investigations into the possibility of using ahigh-pressure water-ice jet as a new method for removing a worn-out paint coating from the surface of metal parts (including those found in means of transportation) and for preparing the base surface for the application of renovation paint coating. Experimental investigations were carried out in four stages, on flat specimens, sized S × H = 75 × 115 mm, cut from sheet metal made of various materials such as steel X5CrNi18-10, PA2 aluminium alloy and PMMA polymethyl methacrylate (plastic). In the first stage, the surfaces of the samples were subjected to observation of surface morphology under a scanning electron microscope, and surface topography (ST) measurements were made on a profilographometer. Two ST parameters were analysed in detail: the maximum height of surface roughness Sz and the arithmetic mean surface roughness Sa. Next, paint coatings were applied to the specimens as a base. In the third stage, the paint coating applied was removed by means of a high-pressure water-ice jet (HPWIJ) by changing the values of the technological parameters, i.e., water jet pressure pw, dry ice mass flow rate m˙L, distance between the sprinkler head outlet and the surface being treated (the so-called working jet length) l2 and spray angle κ for the following constants: the number of TS = 4 holes, water hole diameter φ = 1.2 mm and sprinkler head length Lk = 200 mm. Afterwards, the surface morphology was observed again and the surface topography of the specimen was investigated by measuring selected 3D parameters of the ST structure, Sz and Sa. The results of investigations into the influence of selected HPWIJ treatment parameters on the surface QF removal efficiency obtained are also presented. Univariate regression functions were developed for the mean stripping efficiency based on the following: dry ice mass flow rate m˙L, working jet length l2 and spray angle κ. Based on these functions, the values of optimal parameters were determined that allow the maximum efficiency of the process to be obtained. A 95% confidence region for the regression function was also developed. The results demonstrated that HPWIJ treatment does not interfere with the geometric structure of the base material, and they confirmed the possibility of using this treatment as an efficient method of removing a worn paint layer from bases made of various metal and plastic materials, and preparing it for applying a new layer during renovation.
The Tetrahydrofuran Motif in Polyketide Marine Drugs
Authors: Fernández-Peña Laura , Díez-Poza Carlos , González-Andrés Paula , Barbero Asunción
Published: February 2022

Oxygen heterocycles are units that are abundant in a great number of marine natural products. Among them, marine polyketides containing tetrahydrofuran rings have attracted great attention within the scientific community due to their challenging structures and promising biological activities. An overview of the most important marine tetrahydrofuran polyketides, with a focused discussion on their isolation, structure determination, approaches to their total synthesis, and biological studies is provided.
The Impact of GLP1 Agonists on Bone Metabolism: A Systematic Review
Authors: Daniilopoulou Ioanna , Vlachou Eugenia , Lambrou George I. , Ntikoudi Anastasia , Dokoutsidou Eleni , Fasoi Georgia , Govina Ourania , Kavga Anna , Tsartsalis Athanasios N.
Published: February 2022

Background and Objectives: The association between diabetes mellitus and increased risk of bone fractures has led to the investigation of the impact of antidiabetic drugs on bone metabolism. Glucagon-like peptide-1 receptor agonists (GLP1RAs) are a relatively novel and promising class of anti-hyperglycemic drugs. In addition to their blood glucose lowering action, GLP1RAs seem to have additional pleiotropic properties such as a beneficial skeletal effect; although the underlying mechanisms are not completely understood. The present systematic review summarizes current evidence about GLP1RAs and their effects on bone metabolism and fracture. Methods: An extensive literature search was conducted based on electronic databases namely, PubMed, Google Scholar and Cochrane Central Register of Controlled Trials (CENTRAL) through October 2019 to January 2020 for articles related to bone mineral density, diabetes mellitus and GLP1RAs. We included articles published in English. Finally, we included four randomized controlled trials, three meta-analyses, a case-control study and a population-based cohort analysis. Results: Based on the articles included, the animal studies indicated the salutary skeletal effects of GLP1RAs in opposition to what has been commonly observed in human studies, showing that these agents have no impact on bone mineral density (BMD) and the turnover markers. Moreover, it was demonstrated that GLP1 was not associated with fracture risk as compared to other anti-hyperglycemic drugs. Conclusions: Findings from this systematic review have demonstrated the neutral impact of GLP1RAs on BMD. Moreover, further double-blind randomized controlled trials are needed to draw more meaningful and significant conclusions on the efficacy of GLP1RAs on BMD.
Delayed Bronchial Obstruction following Esophageal Stent Implantation: A Case Report
Authors: Kim Sang Hyun , Choi Hyuk Soon , Keum Bora
Published: February 2022

Airway compression is a rare complication of esophageal stent placement. With the introduction of self-expanding metal stents, the incidence of bronchial obstruction by esophageal stents has decreased. Delayed external airway compression after esophageal stent implantation is rarely reported. We describe a case of left main bronchial obstruction after self-expandable esophageal stent placement. A 70-year-old patient with advanced esophageal cancer visited the emergency room (ER) with worsening cough and dyspnea. He had received palliative concurrent chemoradiotherapy after esophageal self-expanding metal stent (SEMS) insertion three months ago. One month before the ER visit, additional esophageal SEMS placement (stent-in-stent) was performed owing to the development of a tracheoesophageal fistula. After hospitalization, chest radiography revealed a patchy consolidation in the left lower lobe. A diagnosis of pneumonia was made, and the patient was treated with antibiotics. Seven days after antibiotic treatment, the patient developed a fever and severe dyspnea. Auscultation revealed the absence of breath sounds in the left hemithorax. A follow-up chest radiograph showed a white-out of the left hemithorax. Flexible bronchoscopy revealed luminal narrowing of the left main bronchus (LMB) due to external compression. Chest computed tomography further demonstrated compression of the LMB by esophageal stents. This case highlights that esophageal SEMS can present as an emergent and often life-threatening airway obstruction.
Analytical Estimation of Electromagnetic Pressure, Flyer Impact Velocity, and Welded Joint Length in Magnetic Pulse Welding
Authors: Shotri Rishabh , Faes Koen , Racineux Guillaume , De Amitava
Published: February 2022

Magnetic pulse welding involves the joining of two metallic parts in a solid state by the use of a short and intense electromagnetic impulses and the resulting impact between the parts. The coalesced interface undergoes visco-plastic deformation at a high strain rate and exhibits a wavy shape at a microscopic scale. A practical estimation of the electromagnetic pressure, impact velocity and welded joint length as a function of the process conditions and the electromagnetic coil geometry is required but currently not available. Three novel analytical relations for the estimation of the electromagnetic pressure, impact velocity, and welded joint length for magnetic pulse welding of tubes and sheets, are presented. These relations were developed systematically, following a dimensional analysis, and validated for a wide range of conditions from independent literature. The comparison of the analytically computed results and the corresponding values reported in the literature has illustrated that the proposed analytical relations can be used for the estimation of the electromagnetic pressure and impact velocity for the magnetic pulse welding of tubes and sheets with a good level of confidence. The analytically calculated results for the welded joint length show a little discrepancy with the corresponding experimentally measured values. Further investigations and more experimentally measured results are required to arrive at a more comprehensive analytical relation for the prediction of welded joint length.
Comprehensive Peak Characterization (CPC) in Untargeted LC–MS Analysis
Authors: Pirttilä Kristian , Balgoma David , Rainer Johannes , Pettersson Curt , Hedeland Mikael , Brunius Carl
Published: February 2022

LC–MS-based untargeted metabolomics is heavily dependent on algorithms for automated peak detection and data preprocessing due to the complexity and size of the raw data generated. These algorithms are generally designed to be as inclusive as possible in order to minimize the number of missed peaks. This is known to result in an abundance of false positive peaks that further complicate downstream data processing and analysis. As a consequence, considerable effort is spent identifying features of interest that might represent peak detection artifacts. Here, we present the CPC algorithm, which allows automated characterization of detected peaks with subsequent filtering of low quality peaks using quality criteria familiar to analytical chemists. We provide a thorough description of the methods in addition to applying the algorithms to authentic metabolomics data. In the example presented, the algorithm removed about 35% of the peaks detected by XCMS, a majority of which exhibited a low signal-to-noise ratio. The algorithm is made available as an R-package and can be fully integrated into a standard XCMS workflow.
Design and Implementation of an Urban Farming Robot
Authors: Moraitis Michail , Vaiopoulos Konstantinos , Balafoutis Athanasios T.
Published: February 2022

Urban agriculture can be shortly defined as the growing of plants and/or the livestock husbandry in and around cities. Although it has been a common occupation for the urban population all along, recently there is a growing interest in it both from public bodies and researchers, as well as from ordinary citizens who want to engage in self-cultivation. The modern citizen, though, will hardly find the free time to grow his own vegetables as it is a process that requires, in addition to knowledge and disposition, consistency. Given the above considerations, the purpose of this work was to develop an economic robotic system for the automatic monitoring and management of an urban garden. The robotic system was designed and built entirely from scratch. It had to have suitable dimensions so that it could be placed in a balcony or a terrace, and be able to scout vegetables from planting to harvest and primarily conduct precision irrigation based on the growth stage of each plant. Fertigation and weed control will also follow. For its development, a number of technologies were combined, such as Cartesian robots’ motion, machine vision, deep learning for the identification and detection of plants, irrigation dosage and scheduling based on plants’ growth stage, and cloud storage. The complete process of software and hardware development to a robust robotic platform is described in detail in the respective sections. The experimental procedure was performed for lettuce plants, with the robotic system providing precise movement of its actuator and applying precision irrigation based on the specific needs of the plants.
Design and Characterization of a Microfluidic Circuit for Air Particulate Matter Separation
Authors: Li Yongzhen , Xu Yaru , Jiang Jinling , Zhu Xiaofeng , Guo Ruihua , Sun Jianhai
Published: February 2022

Air microfluidic circuits have been widely concerned in the separation of atmospheric particulate matter, especially for portable particulate matter separation detection devices. Currently, no systematic approach for the design and optimization of an air-microfluidic system for PM separation has been reported in the literature. In this paper, a two-stage air microfluidic circuit is designed. The design process is divided into two stages: first, the preliminary design of the structure is completed according to aerodynamic theory. Then, the influences of various factors (such as flow channel width, tilt angle, flow rate, etc.) on the collection efficiency and particle wall loss are explored through numerical analysis to complete the optimization design of the structure. Finally, the air microfluidic circuit is prepared by MEMS processing technology and the particulate matter separation experiments are carried out. The developed two-stage air microfluidic circuit can realize the efficient separation of PM10 and PM2.5. Thus, the important factors affecting the collection efficiency and particle wall loss of air microfluidic circuit are clarified, and a systematic design theory method is formed.
Microplastics Occurrence in Two Mountainous Rivers in the Lowland Area—A Case Study of the Central Pomeranian Region, Poland
Authors: Piskuła Paulina , Astel Aleksander Maria
Published: February 2022

Because of the increasing worldwide awareness concerning the occurrence of microplastics (MPs) in aquatic ecosystems, our goal was to analyze for the first time the quality and abundance of MPs and assess their seasonal variation in two unique rivers flowing through the low-land area in northern Poland. Their uniqueness is due to the fact they flow through landscape parks and urbanized zones, possess mountainous characteristics, and are aquatic habitats for sea trout (Salmo trutta m. trutta) and salmon (Salmo salar). In this pioneering study, the morphological types, geometric dimensions, and color of MP particles were analyzed by the use of an optical microscope. MPs particles were detected in 62.5% of the river water samples, while the average abundance was 3.6–4.2 items per sample. In terms of general seasonality, the sum of MPs items found in investigated river water samples decreased in the following order: spring (75 items) > summer (64 items) > autumn (52 items). Neither the total MPs abundance nor any morphological MPs types were statistically different between rivers according to single seasons. The quantity of MPs present in the river water was higher downstream of the wastewater treatment plant studied, which confirms that treated sewage effluent is a key source of MPs in an aquatic environment. Among the morphological types, fragments were prevalent among granules and fibers, while their average length not exceeding 1.0 mm enabled them to be classified as small. MPs were classified into nine colors, however, the bright colors were dominating only in the case of granule. In the case of the fragments and fibers, the dominating colors were transparent, white, blue, and black. Fourier transform infrared spectroscopy was performed on a small sample of microplastics (21.0%) due to their small size. Polymers containing polyethylene, polyvinyl chloride, polypropylene, polyester, and polystyrene were identified.
Sand and Pebbles: The Study of Portuguese Raw Materials for Provenance Archaeological Glass
Authors: Coutinho Inês , Medici Teresa , Gratuze Bernard , Ruivo Andreia , Dinis Pedro , Lima Augusta , Vilarigues Márcia
Published: February 2022

Portuguese archaeological excavations dated to the 17th century onwards are extremely rich in glass artefacts, with this being a reality from the north to the south of the territory. Contrasting with this reality, no glass production locations from this period have been discovered or excavated so far, which makes the provenance attribution a challenging endeavour. One specific archaeological location, the Monastery of Santa Clara-a-Velha in Coimbra, held one of the largest glass archaeological assemblages dated to the 17th century unearthed in Portugal so far. Due to the large variety of objects’ shapes, glass colours and decorative features, this assemblage is a valuable candidate to hold glass artefacts produced in Portugal. Lacking archaeological excavation on glass furnaces in Portugal, the study of glassmaking raw materials is the most promising research line to investigate the provenance of glass circulating in Portugal. In this study, sand and pebbles from six different locations in the north/centre of Portugal were collected and melted to produce glass samples. The resulting glass samples were chemically characterised using LA-ICP-MS, to obtain the composition of the samples in major, minor and trace elements. The obtained results were compared with the composition of 37 historical samples from the Monastery of Santa Clara-a-Velha previously studied. Additionally, the thermal properties of selected synthesised glasses were analysed by Differential Scanning Calorimetry, allowing new insights on melting temperatures and glass workability. Results indicate that three artefacts with stylistic features attributed to a Portuguese production were locally made with sands collected in Coimbra.
Integrative Study Assessing Space and Time Variations with Emphasis on Rare Earth Element (REE) Distribution and Their Potential on Ashes from Commercial (Colombian) Coal
Authors: Santos Ana Cláudia , Guedes Alexandra , French David , Futuro Aurora , Valentim Bruno
Published: February 2022

The increasing demand for rare earth elements (REEs), which is associated with their economic importance and the supply risk, has motivated the research for alternative secondary sources of these elements. Coal and coal combustion ash have been pointed out as promising REE raw materials. This research seeks to understand REE fractionation, from feed coals to ashes, considering seasonal variations, and to assess the trends within the ash fractions that can be used for further beneficiation processes. Colombian commercial feed coals, combustion ashes, and their respective fractions were sampled from a Portuguese power plant and were characterized via petrographical, mineralogical, and chemical analyses. The total REE concentrations in the feed coals studied range between 6.97 and 23.15 ppm, while, in the ashes, they vary from 159.9 to 266.6 ppm. Fly ash (FA) from electrostatic precipitator (ESP) presented higher concentrations than the bottom (BA) and economizer (ECO) ashes. Furthermore, REEs and the LREE/HREE ratio increased slightly towards the back rows of the ESP. In the feed coals, the REEs are significantly correlated with ash, and they occur in micrometric phosphate minerals intermixed with clays. In the ashes, the REEs were mostly detected in micrometric particles, with P and Al-Si as the major components. The results from the fractioned samples show that the REEs were enriched in the fine (<25 µm) and nonmagnetic fractions of the ESP FA. A single trial combining sieving and magnetic separation enabled the attainment of a REE recovery of 53%, and a final enrichment factor of 1.25. Coal combustion ashes and their respective size fractions are promising REE raw materials; however, the REE oxide concentrations are below the economical cutoff of 1000 ppm.
Biological Activity of an Epilobium angustifolium L. (Fireweed) Infusion after In Vitro Digestion
Authors: Kowalik Klaudia , Polak-Berecka Magdalena , Prendecka-Wróbel Monika , Pigoń-Zając Dominika , Niedźwiedź Iwona , Szwajgier Dominik , Baranowska-Wójcik Ewa , Waśko Adam
Published: February 2022

The biological activity of an in vitro digested infusion of Epilobium angustifolium (fireweed) was examined in a model system of intestinal epithelial and colon cancer tissues. The content of selected phenolic compounds in the digested aqueous extract of fireweed was determined using HPLC-ESI-QTOF-MS/MS. Biological activity was examined using the human colon adenocarcinoma cell lines HT-29 and CaCo-2 and the human colon epithelial cell line CCD 841 CoTr. Cytotoxicity was assessed by an MTT assay, a Neutral Red uptake assay, May-Grünwald-Giemsa staining, and a label-free Electric Cell-Substrate Impedance Sensing cytotoxicity assay. The effect of the infusion on the growth of selected intestinal bacteria was also examined. The extract inhibited the growth of intestinal cancer cells HT-29. This effect can be attributed to the activity of quercetin and kaempferol, which were the most abundant phenolic compounds found in the extract after in vitro digestion. The cytotoxicity of the fireweed infusion was dose-dependent. The highest decrease in proliferation (by almost 80%) compared to the control was observed in HT-29 line treated with the extract at a concentration of 250 μg/mL. The fireweed infusion did not affect the growth of beneficial intestinal bacteria, but it did significantly inhibit E. coli. The cytotoxic effect of the fireweed extract indicates that it does not lose its biological activity after in vitro digestion. It can be concluded that the fireweed infusion has the potential to be used as a supporting agent in colon cancer therapy.
Recent Advances in Macrocyclic Drugs and Microwave-Assisted and/or Solid-Supported Synthesis of Macrocycles
Authors: Sun Dianqing
Published: February 2022

Macrocycles represent attractive candidates in organic synthesis and drug discovery. Since 2014, nineteen macrocyclic drugs, including three radiopharmaceuticals, have been approved by FDA for the treatment of bacterial and viral infections, cancer, obesity, immunosuppression, etc. As such, new synthetic methodologies and high throughput chemistry (e.g., microwave-assisted and/or solid-phase synthesis) to access various macrocycle entities have attracted great interest in this chemical space. This article serves as an update on our previous review related to macrocyclic drugs and new synthetic strategies toward macrocycles (Molecules, 2013, 18, 6230). In this work, I first reviewed recent FDA-approved macrocyclic drugs since 2014, followed by new advances in macrocycle synthesis using high throughput chemistry, including microwave-assisted and/or solid-supported macrocyclization strategies. Examples and highlights of macrocyclization include macrolactonization and macrolactamization, transition-metal catalyzed olefin ring-closure metathesis, intramolecular C–C and C–heteroatom cross-coupling, copper- or ruthenium-catalyzed azide–alkyne cycloaddition, intramolecular SNAr or SN2 nucleophilic substitution, condensation reaction, and multi-component reaction-mediated macrocyclization, and covering the literature since 2010.
Sustainability Evaluation of Immobilized Acid-Adapted Microalgal Technology in Acid Mine Drainage Remediation following Emergy and Carbon Footprint Analysis
Authors: Praveen Kuppan , Abinandan Sudharsanam , Venkateswarlu Kadiyala , Megharaj Mallavarapu
Published: February 2022

Sustainability evaluation of wastewater treatment helps to reduce greenhouse gas emissions, as it emphasizes the development of green technologies and optimum resource use rather than the end-of-pipe treatment. The conventional approaches for treating acid mine drainages (AMDs) are efficient; however, they need enormous amounts of energy, making them less sustainable and causing greater environmental concern. We recently demonstrated the potential of immobilized acid-adapted microalgal technology for AMD remediation. Here, this novel approach has been evaluated following emergy and carbon footprint analysis for its sustainability in AMD treatment. Our results showed that imported energy inputs contributed significantly (>90%) to the overall emergy and were much lower than in passive and active treatment systems. The microalgal treatment required 2–15 times more renewable inputs than the other two treatment systems. Additionally, the emergy indices indicated higher environmental loading ratio and lower per cent renewability, suggesting the need for adequate renewable inputs in the immobilized microalgal system. The emergy yield ratio for biodiesel production from the microalgal biomass after AMD treatment was >1.0, which indicates a better emergy return on total emergy spent. Based on greenhouse gas emissions, carbon footprint analysis (CFA), was performed using default emission factors, in accordance with the IPCC standards and the National Greenhouse Energy Reporting (NGER) program of Australia. Interestingly, CFA of acid-adapted microalgal technology revealed significant greenhouse gas emissions due to usage of various construction materials as per IPCC, while SCOPE 2 emissions from purchased electricity were evident as per NGER. Our findings indicate that the immobilized microalgal technology is highly sustainable in AMD treatment, and its potential could be realized further by including solar energy into the overall treatment system.
Organic Thermoelectric Materials as the Waste Heat Remedy
Authors: Gogoc Szymon , Data Przemyslaw
Published: February 2022

The primary reason behind the search for novel organic materials for application in thermoelectric devices is the toxicity of inorganic substances and the difficulties associated with their processing for the production of thin, flexible layers. When Thomas Seebeck described a new phenomenon in Berlin in 1820, nobody could have predicted the future applications of the thermoelectric effect. Now, thermoelectric generators (TEGs) are used in watches, and thermoelectric coolers (TECs) are applied in cars, computers, and various laboratory equipment. Nevertheless, the future of thermoelectric materials lies in organic compounds. This paper discusses the developments made in thermoelectric materials, including small molecules, polymers, molecular junctions, and their applications as TEGs and/or TECs.
The Effect of Supramolecular Humic Acids on the Diffusivity of Metal Ions in Agarose Hydrogel
Authors: Klučáková Martina
Published: February 2022

Humic acids are known as natural substances of a supramolecular nature. Their self-assembly ability can affect the migration of heavy metals and other pollutants in nature. The formation of metal-humic complexes can decrease their mobility and bioavailability. This study focuses on metal ions diffusion and immobilization in humic hydrogels. Humic acids were purchased from International Humic Substances Society (isolated from different matrices—peat, soil, leonardite, water) and extracted from lignite mined in Czech Republic. Copper(II) ions were chosen as a model example of reactive metals for the diffusion experiments. The model of instantaneous planar source was used for experimental data obtained from monitoring the time development of copper(II) ions distribution in hydrogel. The effective diffusion coefficients of copper(II) ions showed the significant dependence on reaction ability of humic hydrogels. Lower amounts of the acidic functional groups caused an increase in the effective diffusion coefficient. In general, diffusion experiments seem to act as a valuable method for reactivity mapping studies on humic substances.
Synthesis, Nanoformulations, and In Vitro Anticancer Activity of N-Substituted Side Chain Neocryptolepine Scaffolds
Authors: El Sayed Ibrahim El-Tantawy , Ullah Sami , Al-Hartomy Omar A. , Hasanein Asmaa Mohammed , Ahmed Abdullah A. S. , Kahilo Khaled A. , El-Naggar Mehrez E.
Published: February 2022

The naturally occurring neocryptolepine (5-Methylindolo [2,3-b]quinoline) and its analogs exhibited prominent anticancer and antimalarial activity. However, the main problem of this class of compounds is their poor aqueous solubility, hampering their bioavailability and preventing their clinical development. To overcome the problem of insolubility and to improve the physicochemical and the pharmacological properties of 5-Methylindolo [2,3-b]quinoline compounds, this work was designed to encapsulate such efficient medical compounds into mesoporous silica oxide nanoemulsion (SiO2NPs). Thus, in this study, SiO2NPs was loaded with three different concentrations (0.2 g, 0.3, and 0.6 g) of 7b (denoted as NPA). The findings illustrated that the nanoparticles were formed with a spherical shape and exhibited small size (less than 500 nm) using a high concentration of the synthesized chemical compound (NPA, 0.6 g) and good stabilization against agglomeration (more than −30 mv). In addition, NPA-loaded SiO2NPs had no phase separation as observed by our naked eyes even after 30 days. The findings also revealed that the fabricated SiO2NPs could sustain the release of NPA at two different pH levels, 4.5 and 7.4. Additionally, the cell viability of the produced nanoemulsion system loaded with different concentrations of NPA was greater than SiO2NPs without loading, affirming that NPA had a positive impact on increasing the safety and cell viability of the whole nanoemulsion. Based on these obtained promising data, it can be considered that the prepared NPA-loaded SiO2NPs seem to have the potential for use as an effective anticancer drug nanosystem.