bluuebunny/crossref_metadata_2025 huggingface dataset:
Suppressive Effects of Siegesbeckia orientalis Ethanolic Extract on Proliferation and Migration of Hepatocellular Carcinoma Cells through Promoting Oxidative Stress, Apoptosis and Inflammatory Responses
Authors: Chen Tzu-Hua , Chang Chi-Chang , Houng Jer-Yiing , Chang Tzu-Hsien , Chen Ya-Ling , Hsu Chia-Chang , Chang Long-Sen
Published: July 2022

Previous studies have demonstrated that Siegesbeckia orientalis (SO) has a suppressive effect on the growth and migration of endometrial and cervical cancer cells. The present study examined the effect of SO ethanolic extract (SOE) on the proliferation and migration of hepatocellular carcinoma (HCC) and examined the effects of SOE on non-cancerous cells using HaCaT keratinocytes as a model. The SOE effectively inhibited the proliferation of Hepa1-6 (IC50 = 282.4 μg/mL) and HepG2 (IC50 = 344.3 μg/mL) hepatoma cells, whereas it has less cytotoxic effect on HaCaT cells (IC50 = 892.4 μg/mL). The SOE treatment increased the generation of ROS in HCC, but decreased the expression of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase and catalase. In contrast, it reduced intracellular ROS formation and upregulated the expression of the related antioxidant enzymes in the H2O2-stimulated HaCaT cells. The SOE intervention also down-regulated the anti-apoptotic Bcl-2 and the migration-related proteins including matrix metalloproteinases (MMPs) and β-catenin in the HCC, suggesting that SOE could promote HCC apoptosis and inhibit HCC migration. On the contrary, it reduced apoptosis and promoted the migration of the keratinocytes. Additionally, the SOE treatment significantly up-regulated the pro-inflammatory cytokines, including TNF-α, IL-6 and IL-1β, in Hepa1-6 and HepG2 cells. Conversely, it significantly decreased the expression of these cytokines in the H2O2-induced HaCaT cells. These findings indicated that SOE treatment can delay the progression of HCC by increasing oxidative stress, promoting inflammatory response, inducing cancer cell apoptosis and inhibiting their migration. It also has protective effects from pro-oxidant H2O2 in non-cancerous cells. Therefore, SOE may provide a potential treatment for liver cancer.
Removal of Circulating Tumor Cells from Blood Samples of Cancer Patients Using Highly Magnetic Nanoparticles: A Translational Research Project
Authors: Doswald Simon , Herzog Antoine F. , Zeltner Martin , Zabel Anja , Pregernig Andreas , Schläpfer Martin , Siebenhüner Alexander , Stark Wendelin J. , Beck-Schimmer Beatrice
Published: July 2022

The count of circulating tumor cells (CTCs) has been associated with a worse prognosis in different types of cancer. Perioperatively, CTCs detach due to mechanical forces. Diagnostic tools exist to detect and isolate CTCs, but no therapeutic technique is currently available to remove CTCs in vivo from unprocessed blood. The aim of this study was to design and test new magnetic nanoparticles to purify whole blood from CTCs. Novel magnetic carbon-coated cobalt (C/Co) nanoparticles conjugated with anti-epithelial cell adhesion molecule (EpCAM) antibodies were synthesized, and their antifouling and separation properties were determined. The newly developed C/Co nanoparticles showed excellent separation and antifouling properties. They efficiently removed tumor cells that were added to healthy subjects’ blood samples, through an anti-EpCAM antibody interaction. The nanoparticles did not interact with other blood components, such as lymphocytes or the coagulation system. In blood samples of carcinoma patients suffering from metastatic disease, on average, ≥68% of CTCs were removed. These nanoparticles could prompt the development of a blood purification technology, such as a dialysis-like device, to perioperatively remove CTCs from the blood of cancer patients in vivo and potentially improve their prognosis.
A kNGR Peptide-Tethered Lipid–Polymer Hybrid Nanocarrier-Based Synergistic Approach for Effective Tumor Therapy: Development, Characterization, Ex-Vivo, and In-Vivo Assessment
Authors: Gupta Madhu , Sharma Vikas , Sharma Kalicharan , Kumar Anoop , Sharma Ajay , Kazmi Imran , Al-Abbasi Fahad A. , Alzarea Sami I. , Afzal Obaid , Altamimi Abdulmalik Saleh Alfawaz , Singh Sachin Kumar , Gupta Gaurav , Paudel Keshav Raj , Hansbro Philip M. , Dua Kamal
Published: July 2022

The present study aims to design, develop and characterize kNGR (Asn-Gly-Arg) peptide-conjugated lipid–polymer-based nanoparticles for the target-specific delivery of anticancer bioactive(s), i.e., Paclitaxel (PTX). The kNGR-PEG-DSPE conjugate was synthesized and characterized by using spectral analysis. The dual-targeted PLGA–lecithin–PEG core-shell nanoparticles (PLNs-kNGR-NPs) were synthesized using a modified nanoprecipitation process, and their physiological properties were determined. The results support that, compared to other NPs, PLNs-kNGR-NPs are highly cytotoxic, owing to higher apoptosis and intracellular uptake. The significance of rational nanoparticle design for synergistic treatment is shown by the higher tumor volume inhibition percentage rate (59.7%), compared to other designed formulations in Balb/c mice in the HT-1080 tumor-induced model. The overall results indicate that the PLNs-kNGR-NPs-based hybrid lipid–polymer nanoparticles present the highest therapeutic efficacy against solid tumor overexpressing the CD13 receptors.
A Comprehensive Review of the Evolution of Insulin Development and Its Delivery Method
Authors: Sugumar Vaisnevee , Ang Kuan Ping , Alshanon Ahmed F. , Sethi Gautam , Yong Phelim Voon Chen , Looi Chung Yeng , Wong Won Fen
Published: July 2022

The year 2021 marks the 100th anniversary of the momentous discovery of insulin. Through years of research and discovery, insulin has evolved from poorly defined crude extracts of animal pancreas to recombinant human insulin and analogues that can be prescribed and administered with high accuracy and efficacy. However, there are still many challenges ahead in clinical settings, particularly with respect to maintaining optimal glycemic control whilst minimizing the treatment-related side effects of hypoglycemia and weight gain. In this review, the chronology of the development of rapid-acting, short-acting, intermediate-acting, and long-acting insulin analogues, as well as mixtures and concentrated formulations that offer the potential to meet this challenge, are summarized. In addition, we also summarize the latest advancements in insulin delivery methods, along with advancement to clinical trials. This review provides insights on the development of insulin treatment for diabetes mellitus that may be useful for clinicians in meeting the needs of their individual patients. However, it is important to note that as of now, none of the new technologies mentioned have superseded the existing method of subcutaneous administration of insulin.
Development and Validation of Comprehensive Healthcare Providers’ Opinions, Preferences, and Attitudes towards Deprescribing (CHOPPED Questionnaire)
Authors: Bužančić Iva , Ortner Hadžiabdić Maja
Published: July 2022

Successful implementation of deprescribing requires exploring healthcare professionals’ opinions, preferences, and attitudes towards deprescribing. The aim of this study was to develop and validate the questionnaire exploring healthcare providers’ opinions preferences and attitudes towards deprescribing (CHOPPED questionnaire). This was a cross-sectional on-line survey. A comprehensive 58-item questionnaire, in two versions (for pharmacists and physicians), was developed through an extensive literature review and interviews with experts. The questionnaire was validated, and its reliability was assessed through data collected from 356 pharmacists and 109 physicians. Exploratory factor analysis was performed, and 37- and 35-item questionnaires were developed. Ten factors were identified: knowledge, awareness, patient barriers and facilitators, competencies barriers and facilitators, collaboration barriers and facilitators, and healthcare system barriers and facilitators. The CHOPPED tool has satisfactory face, content (CVR > 0.62) (content validity ratio), construct, and criterion validity. The reliability statistics of all factors in both versions was acceptable with Cronbach’s alpha > 0.6. Test–retest reliability analysis showed that gamma rank correlations of total factor scores were strong and very strong (between 0.519 and 0.938). The CHOPPED tool can be used as a valid and reliable tool to explore healthcare providers’ opinions and attitudes toward discontinuing medications in the primary care setting in Croatia.
Closing the Integration Gap: A Pilot for Incorporating Foundational Sciences, DEI-Decision Making, Empathy, and Communication for Congestive Heart Failure and Arrhythmia Management by Pharmacy Students
Authors: Malhotra Ashim , Oh Song , Jin Zhuqiu , Feng Xiaodong
Published: July 2022

Pharmacists must integrate foundational sciences with pharmacy practice for providing optimal patient care. Pharmacy students need to be trained to provide culturally competent, linguistically accessible, and empathetic care while integrating foundational science principles. However, such holistic integration is challenging to achieve and assess. To bridge this gap, we implemented and assessed an “integrated cardiovascular simulation” (ICS) module for P2 students, employing case-based and team-based learning. ICS focused on congestive heart failure with preexisting arrhythmia and incorporated patient counseling relating to diversity factors such as cultural competency, linguistic challenges, and the impact of population diversity on cardiac diseases. Students learned the SBAR communication technique (situation, background, assessment, and recommendation) and recommended therapy while elaborating on drug MOA and adverse effects. ICS was assessed through pre-and post-session quizzes and perception data immediately after the activity, and after two years, when students progressed to the cardiovascular APPE block. Student performance improved on a post-test (80.2%) compared to the pre-test (66.9%), p < 0.01 paired student t-test, with an increase in symptom and arrhythmia pattern recognition (41.2% and 36.7%, respectively). ICS was effective for teaching (1) arrhythmia pathophysiology (85%), (2) EKG interpretation (89%), (3) drug adverse effects (93%), (4) DEI-clinical decision making (92%), and (5) communication skills (85%).
Enactivism and Material Culture: How Enactivism Could Redefine Enculturation Processes
Authors: Monterroza-Rios Alvaro David , Gutiérrez-Aguilar Carlos Mario
Published: July 2022

Culture has traditionally been considered as a set of knowledge, beliefs, arts, laws, norms, and morals, acquired by a human being as a member of a group. Some anthropologists interpret this as a set of abstract representations, such as information or knowledge, while others interpret it as behavioral control mechanisms. These views assume that the contents of a particular culture must be processed by the minds of individuals, either in a direct way or by resorting to learned mental structures in processes of symbolic socialization. Some critics suggest a problem with these perspectives since they do not provide a convincing explanation of the enculturation process beyond metaphorical images of transfer or internalization of symbolic cultural contents through linguistic transmission. The new embodied theories of cognition, especially enactivism, could give new ideas about what enculturation processes are like, through the concept of participatory sense-making in material culture environments. In this essay, we discuss how an enactive vision of culture could be, and what advantages it would have, as well as the challenges and weaknesses in explaining the culture and its learning processes.
Potential Distribution of and Sensitivity Analysis for Urochloa panicoides Weed Using Modeling: An Implication of Invasion Risk Analysis for China and Europe
Authors: Duque Tayna Sousa , da Silva Ricardo Siqueira , Maciel Josiane Costa , Silva Daniel Valadão , Fernandes Bruno Caio Chaves , Júnior Aurélio Paes Barros , Santos José Barbosa dos
Published: July 2022

Urochloapanicoides P. Beauv. is considered one of the most harmful weeds in the United States and Australia. It is invasive in Pakistan, Mexico, and Brazil, but its occurrence is hardly reported in China and European countries. Species distribution models enable the measurement of the impact of climate change on plant growth, allowing for risk analysis, effective management, and invasion prevention. The objective of this study was to develop current and future climate models of suitable locations for U. panicoides and to determine the most influential climatic parameters. Occurrence data and biological information on U. panicoides were collected, and climatic parameters were used to generate the Ecoclimatic Index (EI) and to perform sensitivity analysis. The future projections for 2050, 2080, and 2100 were modeled under the A2 SRES scenario using the Global Climate Model, CSIRO-Mk3.0 (CS). The potential distribution of U. panicoides coincided with the data collected, and the reliability of the final model was demonstrated. The generated model identified regions where the occurrence was favorable, despite few records of the species. Sensitivity analysis showed that the most sensitive parameters of the model were related to temperature, humidity, and cold stress. Future projections predict reductions in climate suitability for U. panicoides in Brazil, Australia, India, and Africa, and an increase in suitability in Mexico, the United States, European countries, and China. The rise in suitability of China and Europe is attributed to predicted climate change, including reduction in cold stress. From the results obtained, preventive management strategies can be formulated against the spread of U. panicoides, avoiding economic and biodiversity losses.
The Hidden Potential of High-Throughput RNA-Seq Re-Analysis, a Case Study for DHDPS, Key Enzyme of the Aspartate-Derived Lysine Biosynthesis Pathway and Its Role in Abiotic and Biotic Stress Responses in Soybean
Authors: Kiekens Raphaël , de Koning Ramon , Toili Mary Esther Muyoka , Angenon Geert
Published: July 2022

DHDPS is a key enzyme in the aspartate-derived lysine biosynthesis pathway and an evident object of study for biofortification strategies in plants. DHDPS isoforms with novel regulatory properties in Medicago truncatula were demonstrated earlier and hypothesized to be involved in abiotic and biotic stress responses. Here, we present a phylogenetic analysis of the DHPDS gene family in land plants which establishes the existence of a legume-specific class of DHDPS, termed DHDPS B-type, distinguishable from the DHDPS A-type commonly present in all land plants. The G. max genome comprises two A-type DHDPS genes (Gm.DHDPS-A1; Glyma.09G268200, Gm.DHDPS-A2; Glyma.18G221700) and one B-type (Gm.DHDPS-B; Glyma.03G022300). To further investigate the expression pattern of the G. max DHDPS isozymes in different plant tissues and under various stress conditions, 461 RNA-seq experiments were exploited and re-analyzed covering two expression atlases, 13 abiotic and 5 biotic stress studies. Gm.DHDPS-B is seen almost exclusively expressed in roots and nodules in addition to old cotyledons or senescent leaves while both DHDPS A-types are expressed constitutively in all tissues analyzed with the highest expression in mature seeds. Furthermore, Gm.DHDPS-B expression is significantly upregulated in some but not all stress responses including salt stress, flooding, ethylene or infection with Phytophthora sojae and coincides with downregulation of DHDPS A-types. In conclusion, we demonstrate the potential of an in-depth RNA-seq re-analysis for the guidance of future experiments and to expand on current knowledge.
Photosynthetic Variability of Oblačinska Sour Cherry Ecotypes under Drought
Authors: Viljevac Vuletić Marija , Horvat Daniela , Mihaljević Ines , Dugalić Krunoslav , Šimić Domagoj , Čupić Tihomir , Jurković Vlatka , Lepeduš Hrvoje
Published: July 2022

The selection of drought-tolerant sour cherry genotypes is essential for developing sustainable fruit production in today’s climate-change conditions. The phenotypic heterogenic population of sour cherry Oblačinska, with high and regular yield suitable for mechanical harvesting and industrial processing, is a traditional and predominant cultivar in northern Croatia (Pannonian region) and Serbia commercial orchards. In this context, 2-year old virus-free sour cherry plants of 4 isolated Oblačinska sour cherry ecotypes (OS, 18, D6, and BOR) produced by micropropagation were exposed to severe drought in a greenhouse under semi-controlled conditions to evaluate its photosynthetic intra-varietal variability. Relative water content (RWC), chlorophyll fluorescence (ChlF), and photosynthetic pigments were evaluated during the ten days of the experiment. As a visible symptom of stress, the withering of plants was followed by a diminution of RWC and photosynthetic pigments in the drought exposed leaves of sour cherry ecotypes compared to the control treatment. ChlF elucidated variability in the photosynthetic efficiency within studied sour cherry ecotypes, highlighting PIABS, PItotal, and ψE0 as the most sensitive and thus the most informative JIP parameters for drought screening. Among the investigated ecotypes, BOR proved to be the most sensitive. The Oblačinska sour cherry ecotype OS showed the highest tolerance to drought conditions and, therefore, can be used as a source of tolerance in sour cherry breeding programs.
An Interplay of Light and Smoke Compounds in Photoblastic Seeds
Authors: Bączek-Kwinta Renata
Published: July 2022

Light increases the germinability of positively photoblastic seeds and inhibits the germination of negative ones. In an area where plant-generated smoke from fire is a periodically occurring environmental factor, smoke chemicals can affect the germination of seeds, including those that are photoblastically sensitive. Moreover, as smoke and its compounds, mostly karrikin 1, KAR1, have been used for priming the seeds of many species, including photoblastic ones, a systematic review of papers dealing with the phenomenon was conducted. The review indicates that the unification of experimental treatments (light spectrum, intensity and photoperiod, and KAR1 concentration within the species) could improve the quality of global research on the impact of smoke chemicals on photoblastic seeds, also at the molecular level. The review also reveals that the physiologically active concentration of KAR1 varies in different species. Moreover, the physiological window of KAR’s impact on germination can be narrow due to different depths of primary seed dormancy. Another concern is the mode of action of different smoke sources and formulations (aerosol smoke, smoke-saturated water), or pure smoke chemicals. The reason for this concern is the additive or synergetic effect of KARs, cyanohydrins, nitrates and other compounds, and the presence of a germination inhibitor, trimethylbutenolide (TMB) in smoke and its formulations. Obviously, environmental factors that are characteristic of the local environment need to be considered. From a practical perspective, seeds germinating faster in response to smoke chemicals can outcompete other seeds. Hence, a thorough understanding of this phenomenon can be useful in the restoration of plant habitats and the protection of rare species, as well as yielding an improvement in plants that are sown directly to the field. On the other hand, the application of smoke compounds can induce “suicidal germination” in the photoblastic seeds that are buried in the soil and deplete the soil seed bank of the local population of unwanted species.
Genetic Analysis in Grain Legumes [Vigna radiata (L.) Wilczek] for Yield Improvement and Identifying Heterotic Hybrids
Authors: Azam Md. Golam , Sarker Umakanta , Hossain Md. Amir , Iqbal Md. Shahin , Islam Md. Rafiqul , Hossain Md. Faruk , Ercisli Sezai , Kul Raziye , Assouguem Amine , AL-Huqail Arwa Abdulkreem , R. H. Mohamed Hanan , Peluso Ilaria
Published: July 2022

Six mungbean parental lines and their fifteen F1s produced from half-diallel mating design were investigated for combining ability and heterosis in terms of a yield and its components. Results showed highly significant variations among the parents and F1s, suggesting a wide genetic variability for the studied characters. Analysis of variance indicated that genotypes mean square values, general combining ability (GCA) and specific combining ability (SCA) were highly significant (p ≤ 0.001) for all measured traits except for days to flowering, days to maturity, and pod length indicating genetic diversity of parents and both additive and non-additive gene effects in the inheritance of the measured traits. A higher effect of SCA than GCA for plant height and seeds per pod suggests the preponderance of non-additive gene effects in the expression of characters. Based on per se performance and GCA, BARI Mung-1, PS-7, and BMXK1-14004 were the best general combiners for yield per plant. In the context of SCA, hybrids BMXK1-14004 × Sonali mung, BMXK1-14004 × PS-7, BMXK1-14004 × BINA Mung-8, Sukumar × PS-7, and BARI Mung-1 × BINA Mung-8 were good specific combiners. BMXK1-14004 × Sonali mung and BMXK1-14004 × PS-7 were the best heterotic hybrids for yield and yield-contributing traits. These parents and crosses could be utilized for further use in breeding programs to improve yields in mungbean crops.
Lyophilic and Sorption Properties of Chitosan Aerogels Modified with Copolymers Based on Glycidyl Methacrylate and Alkyl Methacrylates
Authors: Yartseva Vitalia , Makevnina Olga , Bryuzgina Ekaterina , Bryuzgin Evgeny , Klimov Viktor , Kolyaganova Olga , Nikolitchev Dmitry , Navrotsky Alexander , Novakov Ivan
Published: July 2022

This paper discusses the influence of the structure of copolymers based on glycidyl methacrylate and alkyl methacrylates with C6–C18 hydrocarbon side groups on the wettability and sorption properties of surface-modified chitosan aerogels. The grafting of copolymers onto the surface of aerogels was confirmed by elemental analysis, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy. As a result of the modification, with an increase in the amount of the hydrocarbon substituent alkyl methacrylate, the surface of the resulting materials became hydrophobic with contact angles in the range of 146–157°. At the same time, the water absorption of the aerogels decreased by a factor of 30 compared to that for unmodified aerogels, while the sorption capacity for light oil, diesel fuel, and synthetic motor oil remained at the level of more than 30 g/g. Chitosan aerogels with grafted copolymers based on glycidyl methacrylate and alkyl methacrylates retain biodegradation capacity; however, compared to unmodified chitosan, this process has an induction period.
Influence of Centrifugation Cycles of Natural Rubber Latex on Final Properties of Uncrosslinked Deproteinized Natural Rubber
Authors: Hayeemasae Nabil , Saiwari Sitisaiyidah , Soontaranon Siriwat , Masa Abdulhakim
Published: July 2022

Natural rubber latex (NRL) is a polymer (blend) extracted from the milky sap of para rubber trees. Due to being a natural biopolymer, NRL contains various proteins that may be allergenic to humans when in skin contact. Attempts have been made to use deproteinized natural rubber (DPNR) instead of impure NRL, and the final properties of these two types of rubber tend to differ. Thus, the correlations between their chemistry and properties are of focal interest in this work. DPNR was prepared by incubating NRL with urea, followed by aqueous washing/centrifugation. The physical, mechanical, and dynamic properties of incubated NRL before and after washing/centrifugation were examined to distinguish its influences from those of incubation with urea. According to the findings, the proteins, phospholipids, and chain entanglements were responsible for natural polymer networks formed in the NR. Although the proteins were largely removed from the latex by incubation, the properties of high ammonia natural rubber (HANR) were still maintained in its DPNR form, showing that other network linkages dominated over those contributed by the proteins. In the incubated latex, the naturally occurring linkages were consistently reduced with the number of wash cycles.
Triaxial Mechanical Properties and Mechanism of Waterborne Polyurethane-Reinforced Road Demolition Waste as Road Bases
Authors: Lv Beifeng , Zhao Yinuo , Li Na , Yu Yanfei , Wu Yanting , Gu Miaojie
Published: July 2022

The recycling and reuse of construction waste have not only effectively protected natural resources but also promoted the sustainable development of the environment. Therefore, in this article, waterborne polyurethane (WPU) as a promising new polymer reinforcement material was proposed to reinforce the road demolition waste (RDW), and the mechanical performance of WPU-reinforced RDW (named PURD) was investigated using triaxial unconsolidated and undrained shear (UU) and Scanning Electron Microscope (SEM) tests. The results showed that under the same curing time and confining pressure, the shear strength of PURD increased with the increase in WPU content. When the WPU content was 6%, the WPU presented the best reinforcement effect on RA. The failure strain of PURD increased with the increase in confining pressure, but increased first and then reduced with the increase in WPU content. The specimens with 5% WPU content showed the best ductility. At the curing time of 7 and 28 days, the internal friction angle and cohesion of PURD increased with the increase in WPU content, and they reached a maximum when the WPU content was 6%. The internal friction angle barely budged, but the cohesion increased obviously. The enhancement effect of WPU was attributed to the spatial reticular membrane structure produced by wrapping and bonding particles with the WPU film. Microscopic analysis showed that with the increase in WPU content, the internal pore and crack size of PURD gradually decreased. As the WPU content increased, the WPU film became increasingly thicker, which increased the adhesion between WPU and RA particles and made the structure of PURD become increasingly denser.
Nonlinear Conductivity and Space Charge Characteristics of SiC/Silicone Rubber Nanocomposites
Authors: Gao Ming-Ze , Li Zhong-Yuan , Sun Wei-Feng
Published: July 2022

To achieve a preferable compatibility between liquid silicone rubber (LSR) and cable main insulation in a cable accessory, we developed SiC/LSR nanocomposites with a significantly higher conductivity nonlinearity than pure LSR, whilst representing a notable improvement in space charge characteristics. Space charge distributions in polarization/depolarization processes and surface potentials of SiC/LSR composites are analyzed to elucidate the percolation conductance and charge trapping mechanisms accounting for nonlinear conductivity and space charge suppression. It is verified that SiC/LSR composites with SiC content higher than 10 wt% represent an evident nonlinearity of electric conductivity as a function of the electric field strength. Space charge accumulations can be inhibited by filling SiC nanoparticles into LSR, as illustrated in both dielectric polarization and depolarization processes. Energy level and density of shallow traps increase significantly with SiC content, which accounts for expediting carrier hopping transport and surface charge decay. Finite-element multiphysics simulations demonstrate that nonlinear conductivity acquired by 20 wt% SiC/LSR nanocomposite could efficiently homogenize an electric field distributed in high-voltage direct current (HVDC) cable joints. Nonlinear conductivities and space charge characteristics of SiC/LSR composites discussed in this paper suggest a feasible modification strategy to improve insulation performances of direct current (DC) cable accessories.
Biosorbents Based on Biopolymers from Natural Sources and Food Waste to Retain the Methylene Blue Dye from the Aqueous Medium
Authors: Blaga Alexandra Cristina , Tanasă Alexandra Maria , Cimpoesu Ramona , Tataru-Farmus Ramona-Elena , Suteu Daniela
Published: July 2022

The use of a biosorbent based on residual biomass from brewing industry (Saccharomyces pastorianus) immobilized in a natural biopolymer (sodium alginate) was investigated for Methylene Blue removal from aqueous medium. Saccharomyces pastorianus, immobilized by a simple entrapment technique and by microencapsulation in alginate was characterized using SEM, EDAX, pHPZC and the biosorption behavior toward organic pollutant, such as cationic dye. The biosorption experiments were studied by assessing, in a first stage, the influence of the most important operational physical parameters on the efficiency of the biosorbent: the initial concentration of the dye, the contact time between phases, the temperature, the dye solution pH, the biosorbent granule size, and the amount of biosorbent. The highest sorption capacity was obtained for the biosorbent obtained by microencapsulation, at pH 9, at biosorbent dose of 5.28 g/L and a contact time of about 100 min. The biosorption equilibrium was then studied by modeling the data on the Langmuir, Freundlich and Dubinin- Radushkevich isotherms. The Langmuir model is best suited for experimental data on both particle sizes leading to a maximum biosorption capacity of 188.679 mg/g at room temperature. The values of the adsorption energy, E, obtained with the help of the Dubinin-Radushkevich model-suggest that the type of mechanism (physical or chemical) involved in the biosorption process depends on the particle size of the biosorbent. The results confirm that the residual microbial biomass of Saccharomyces pastorianus immobilized in a polymeric matrix such as sodium alginate, can be considered an efficient biosorbent in retaining cationic organic dyes present in aqueous solutions in moderate concentrations.
Mechanical Properties of Bambusa Oldhamii and Yushania-Alpina Bamboo Fibres Reinforced Polypropylene Composites
Authors: Dessalegn Yalew , Singh Balkeshwar , Vuure Aart W. van , Rajhi Ali A. , Duhduh Alaauldeen A. , Hossain Nazia , Ahmed Gulam Mohammed Sayeed
Published: July 2022

The current studies aim to measure the mechanical strength based on age, harvesting season and bamboo species in Ethiopia. The bamboo fibres are extracted using a roll milling machine, which was developed by the author. The age groups (1, 2 and 3 years), harvesting months (February and November), and bamboo species (Yushania alpina and Bambusa oldhamii) are the parameters of the current research studies. Prepregs and composites were produced from bamboo fibres and polypropylene. The mechanical properties of bamboo fibres and their composites in Ethiopia have not been investigated by researchers for the composite application so far. The tensile strength, Young’s modulus, and impact strength of injibara (Y. alpina) bamboo fibres reinforced PP composites from the ages of 1– 3 years old in November is 111 ± 9–125 ± 8 MPa, 15 ± 0.9–25 ± 0.72 GPa, and 47 ± 5 KJ/m2–57 ± 6 KJ/m2, whereas, in February, it is 86 ± 3.86–116 ± 10 MPa, 11 ± 0.71–23 ± 1.5 GPa, and 34 ± 4–52 ± 6 KJ/m2, respectively. Moreover, Kombolcha (B. oldhamii), bamboo fibres reinforced PP composites in November are 93 ± 7–111 ± 8 MPa, 7 ± 0.51–17 ± 2.56 GPa, and 39 ± 4–44 ± 5 KJ/m2, whereas, in February, it is 60 ± 5–104 ± 10 MPa, 12 ± 0.95–14 ± 0.92 GPa, and 26 ± 3 KJ/m2–38 ± 4 KJ/m2, respectively. Furthermore, Mekaneselam (Y. alpina) bamboo fibres reinforced PP composites in November are 99 ± 8–120 ± 11 MPa, 9 ± 0.82–16 ± 1.85 GPa, and 37 ± 4 KJ/m2–46 ± 5 KJ/m2, whereas, in February, it is 91 ± 8–110 ± 9 MPa, 8 ± 0.75–14 ± 1.86 GPa, and 34 ± 3 KJ/m2–40 ± 4 KJ/m2, respectively. At two years, November and Injibara bamboo have recorded the highest mechanical properties in the current research studies. Bamboo fiber strength in Ethiopia is comparable to the previous study of bamboo fibres and glass fibres used for composite materials in the automotive industry.
Triblock Copolymer Compatibilizers for Enhancing the Mechanical Properties of a Renewable Bio-Polymer
Authors: Xue Guilian , Sun Bohua , Han Lu , Liu Baichuan , Liang Hongyu , Pu Yongfeng , Tang Hongming , Ma Fangwu
Published: July 2022

Poly(lactic acid) (PLA) is an emerging plastic that has insufficient properties (e.g., it is too brittle) for widespread commercial use. Previous research results have shown that the strength and toughness of basalt fiber reinforced PLA composites (PLA/BF) still need to be improved. To address this limitation, this study aimed to obtain an effective compatibilizer for PLA/BF. Melt-blending of poly(butylene adipate-co-terephthalate) (PBAT) with PLA in the presence of 4,4′-methylene diphenyl diisocyanate (MDI: 0.5 wt% of the total resin) afforded PLA/PBAT-MDI triblock copolymers. The triblock copolymers were melt-blended to improve the interfacial adhesion of PLA/BF and thus obtain excellent performance of the PLA-ternary polymers. This work presents the first investigation on the effects of PLA/PBAT-MDI triblock copolymers as compatibilizers for PLA/BF blends. The resultant mechanics, the morphology, interface, crystallinity, and thermal stability of the PLA-bio polymers were comprehensively examined via standard characterization techniques. The crystallinity of the PLA-ternary polymers was as high as 43.6%, 1.44× that of PLA/BF, and 163.5% higher than that of pure PLA. The stored energy of the PLA-ternary polymers reached 20,306.2 MPa, 5.5× than that of PLA/BF, and 18.6× of pure PLA. Moreover, the fatigue life of the PLA-ternary polymers was substantially improved, 5.85× than that of PLA/PBAT-MDI triblock copolymers. Thus, the PLA/PBAT-MDI triblock copolymers are compatibilizers that improve the mechanical properties of PLA/BF.
Synthetic Route to Conjugated Donor–Acceptor Polymer Brushes via Alternating Copolymerization of Bifunctional Monomers
Authors: Grobelny Anna , Lorenc Karolina , Skowron Łucja , Zapotoczny Szczepan
Published: July 2022

Alternating donor–acceptor conjugated polymers, widely investigated due to their applications in organic photovoltaics, are obtained mainly by cross-coupling reactions. Such a synthetic route exhibits limited efficiency and requires using, for example, toxic palladium catalysts. Furthermore, the coating process demands solubility of the macromolecules, provided by the introduction of alkyl side chains, which have an impact on the properties of the final material. Here, we present the synthetic route to ladder-like donor–acceptor polymer brushes using alternating copolymerization of modified styrene and maleic anhydride monomers, ensuring proper arrangement of the pendant donor and acceptor groups along the polymer chains grafted from a surface. As a proof of concept, macromolecules with pendant thiophene and benzothiadiazole groups were grafted by means of RAFT and metal-free ATRP polymerizations. Densely packed brushes with a thickness up to 200 nm were obtained in a single polymerization process, without the necessity of using metal-based catalysts or bulky substituents of the monomers. Oxidative polymerization using FeCl3 was then applied to form the conjugated chains in a double-stranded (ladder-like) architecture.
Inclusion/Exclusion Behaviors of Small Molecules during Crystallization of Polymers in Miscible PLLA/TAIC Blend
Authors: Yin Lu , Wang Jiayao , Lin Taotao , You Jichun
Published: July 2022

In this work, PLLA/TAIC has been taken as a model system to investigate the inclusion and exclusion of small molecules during the crystallization of polymers in their miscible blend. Our results indicate that it is the growth rate and diameter of PLLA spherulites that dominate the localization of TAIC. On the one hand, crystallization temperature plays an important role. Crystallization at higher temperature corresponds to higher growth rates and a greater diameter of PLLA spherulites. The former improves the ability of PLLA crystals to trap TAIC while the latter leads to a lower volume fraction of space among neighboring PLLA spherulites. The combination of the two contributes to the enhanced inclusion behaviors. On the other hand, when compared to melt crystallization, cold crystallization results in much smaller spherulites (from higher nucleation density) and sufficient space among spherulites, which accounts for the enrichment of TAIC in interspherulitic regions and for its enhanced exclusion. In the adopted polymer–small molecule blend, TAIC can enrich in interspherulitic regions even in its miscible blend with PLLA, which can be attributed to its stronger diffusion ability.
N-(2-Arylethyl)-2-methylprop-2-enamides as Versatile Reagents for Synthesis of Molecularly Imprinted Polymers
Authors: Sobiech Monika , Maciejewska Dorota , Luliński Piotr
Published: July 2022

The paper describes the formation of six aromatic N-(2-arylethyl)-2-methylprop-2-enamides with various substituents in benzene ring, viz., 4-F, 4-Cl, 2,4-Cl2, 4-Br, 4-OMe, and 3,4-(OMe)2 from 2-arylethylamines and methacryloyl chloride in ethylene dichloride with high yields (46–94%). The structure of the compounds was confirmed by 1H NMR, 13C NMR, IR, and HR-MS. Those compounds were obtained to serve as functionalized templates for the fabrication of molecularly imprinted polymers followed by the hydrolysis of an amide linkage. In an exemplary experiment, the imprinted polymer was produced from N-(2-(4-bromophenyl)ethyl)-2-methylprop-2-enamide and divinylbenzene, acting as cross-linker. The hydrolysis of 2-(4-bromophenyl)ethyl residue proceeded and the characterization of material including SEM, EDS, 13C CP MAS NMR, and BET on various steps of preparation was carried out. The adsorption studies proved that there was a high affinity towards the target biomolecules tyramine and L-norepinephrine, with imprinting factors equal to 2.47 and 2.50, respectively, when compared to non-imprinted polymer synthesized from methacrylic acid and divinylbenzene only.
Deep Reinforcement Learning for Integrated Non-Linear Control of Autonomous UAVs
Authors: ud Din Adnan Fayyaz , Mir Imran , Gul Faiza , Mir Suleman , Saeed Nasir , Althobaiti Turke , Abbas Syed Manzar , Abualigah Laith
Published: July 2022

In this research, an intelligent control architecture for an experimental Unmanned Aerial Vehicle (UAV) bearing unconventional inverted V-tail design, is presented. To handle UAV’s inherent control complexities, while keeping them computationally acceptable, a variant of distinct Deep Reinforcement Learning (DRL) algorithm, namely Deep Deterministic Policy Gradient (DDPG) is proposed. Conventional DDPG algorithm after being modified in its learning architecture becomes capable of intelligently handling the continuous state and control space domains besides controlling the platform in its entire flight regime. Nonlinear simulations were then performed to analyze UAV performance under different environmental and launch conditions. The effectiveness of the proposed strategy is further demonstrated by comparing the results with the linear controller for the same UAV whose feedback loop gains are optimized by employing technique of optimal control theory. Results indicate the significance of the proposed control architecture and its inherent capability to adapt dynamically to the changing environment, thereby making it of significant utility to airborne UAV applications.
Proteomics for Biomarker Discovery for Diagnosis and Prognosis of Kidney Transplantation Rejection
Authors: Ramalhete Luís M. , Araújo Rúben , Ferreira Aníbal , Calado Cecília R. C.
Published: July 2022

Renal transplantation is currently the treatment of choice for end-stage kidney disease, enabling a quality of life superior to dialysis. Despite this, all transplanted patients are at risk of allograft rejection processes. The gold-standard diagnosis of graft rejection, based on histological analysis of kidney biopsy, is prone to sampling errors and carries high costs and risks associated with such invasive procedures. Furthermore, the routine clinical monitoring, based on urine volume, proteinuria, and serum creatinine, usually only detects alterations after graft histologic damage and does not differentiate between the diverse etiologies. Therefore, there is an urgent need for new biomarkers enabling to predict, with high sensitivity and specificity, the rejection processes and the underlying mechanisms obtained from minimally invasive procedures to be implemented in routine clinical surveillance. These new biomarkers should also detect the rejection processes as early as possible, ideally before the 78 clinical outputs, while enabling balanced immunotherapy in order to minimize rejections and reducing the high toxicities associated with these drugs. Proteomics of biofluids, collected through non-invasive or minimally invasive analysis, e.g., blood or urine, present inherent characteristics that may provide biomarker candidates. The current manuscript reviews biofluids proteomics toward biomarkers discovery that specifically identify subclinical, acute, and chronic immune rejection processes while allowing for the discrimination between cell-mediated or antibody-mediated processes. In time, these biomarkers will lead to patient risk stratification, monitoring, and personalized and more efficient immunotherapies toward higher graft survival and patient quality of life.
Calculation of an Average Vehicle’s Sideways Acceleration on Small Roundabouts
Authors: Jagelčák Juraj , Gnap Jozef , Kostrzewski Mariusz , Kuba Ondrej , Frnda Jaroslav
Published: July 2022

The calculation of the average sideways acceleration, based on speed and angular velocity on small roundabouts for a vehicle of up to 3.5 t gross vehicle mass, is described in this paper. Calculations of the turning radius are derived from angular velocity and an automatic selection of events, based on the lateral acceleration of the coefficient of variation within a defined time window. The calculation of the turning radius based on speed and angular velocity yields almost identical results to the calculation of the turning radius by the three-point method using GPS coordinates, as described in previous research. This means that the calculation of the turning radius, derived from the speed of GNSS/INS dual-antenna sensor and gyroscope data, yields similar results to those from the computation of the turning radius derived from the coordinates of a GNSS/INS dual-antenna sensor. The research results can be used in the development of sensors to improve road safety.
Detection of Horse Locomotion Modifications Due to Training with Inertial Measurement Units: A Proof-of-Concept
Authors: Pasquiet Benoît , Biau Sophie , Trébot Quentin , Debril Jean-François , Durand François , Fradet Laetitia
Published: July 2022

Detecting fatigue during training sessions would help riders and trainers to optimize their training. It has been shown that fatigue could affect movement patterns. Inertial measurement units (IMUs) are wearable sensors that measure linear accelerations and angular velocities, and can also provide orientation estimates. These sensors offer the possibility of a non-invasive and continuous monitoring of locomotion during training sessions. However, the indicators extracted from IMUs and their ability to show these locomotion changes are not known. The present study aims at defining which kinematic variables and indicators could highlight locomotion changes during a training session expected to be particularly demanding for the horses. Heart rate and lactatemia were measured to attest for the horse’s fatigue following the training session. Indicators derived from acceleration, angular velocities, and orientation estimates obtained from nine IMUs placed on 10 high-level dressage horses were compared before and after a training session using a non-parametric Wilcoxon paired test. These indicators were correlation coefficients (CC) and root mean square deviations (RMSD) comparing gait cycle kinematics measured before and after the training session and also movement smoothness estimates (SPARC, LDLJ). Heart rate and lactatemia measures did not attest to a significant physiological fatigue. However, the statistics show an effect of the training session (p < 0.05) on many CC and RMSD computed on the kinematic variables, indicating a change in the locomotion with the training session as well as on SPARCs indicators (p < 0.05), and revealing here a change in the movement smoothness both in canter and trot. IMUs seem then to be able to track locomotion pattern modifications due to training. Future research should be conducted to be able to fully attribute the modifications of these indicators to fatigue.
Microsoft Azure Kinect Calibration for Three-Dimensional Dense Point Clouds and Reliable Skeletons
Authors: Romeo Laura , Marani Roberto , Perri Anna Gina , D’Orazio Tiziana
Published: July 2022

Nowadays, the need for reliable and low-cost multi-camera systems is increasing for many potential applications, such as localization and mapping, human activity recognition, hand and gesture analysis, and object detection and localization. However, a precise camera calibration approach is mandatory for enabling further applications that require high precision. This paper analyzes the available two-camera calibration approaches to propose a guideline for calibrating multiple Azure Kinect RGB-D sensors to achieve the best alignment of point clouds in both color and infrared resolutions, and skeletal joints returned by the Microsoft Azure Body Tracking library. Different calibration methodologies using 2D and 3D approaches, all exploiting the functionalities within the Azure Kinect devices, are presented. Experiments demonstrate that the best results are returned by applying 3D calibration procedures, which give an average distance between all couples of corresponding points of point clouds in color or an infrared resolution of 21.426 mm and 9.872 mm for a static experiment and of 20.868 mm and 7.429 mm while framing a dynamic scene. At the same time, the best results in body joint alignment are achieved by three-dimensional procedures on images captured by the infrared sensors, resulting in an average error of 35.410 mm.
Electronic Beam-Scanning Antenna Based on a Reconfigurable Phase-Modulated Metasurface
Authors: Zouhdi Zakaria , Ratni Badreddine , Burokur Shah Nawaz
Published: July 2022

Metasurfaces (MSs) have enabled the emergence of new ideas and solutions in the design of antennas and for the control of electromagnetic waves. In this work, we propose to design a directional high-gain reconfigurable planar antenna based on a phase-modulated metasurface. Reconfigurability is achieved by integrating varactor diodes into the elementary meta-atoms composing the metasurface. As a proof of concept, a metasurface prototype that operates around 5 GHz is designed and fabricated to be tested in an antenna configuration. The metasurface is flexibly controlled by different bias voltages applied to the varactor diodes, thus allowing the user to control its phase characteristics. By assigning judiciously calculated phase profiles to the metasurface illuminated by a feeding primary source, different scenarios of far-field patterns can be considered. Different phase profiles are tested, allowing us to, firstly, achieve a highly directive boresight radiation and, secondly, to steer the main radiated beam towards an off-normal direction. The whole design process is verified by numerical simulations and is validated experimentally by far-field antenna measurements. The proposed metasurface enables the design of directive flat antennas with beam-scanning characteristics without complex feeding systems and power-consuming phase shifters, and thus provides potential interests for next generation antenna hardware.