bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of the Properties of In Vitro Dactylorhiza maculata (L.) Soó (Family Orchidaceae) Extracts
Authors: Sukhikh Stanislav , Noskova Svetlana , Ivanova Svetlana , Skrypnik Liubov , Pungin Artem , Ulrikh Elena , Chupakhin Evgeny , Babich Olga
Published: June 2021

The medicinal plant Dactylorhiza maculata (L.) Soó (family Orchidaceae) is used to treat gastritis, colic, gastrointestinal tract, and bladder diseases. This study aimed to investigate the properties and characteristics of the in vitro Dactylorhiza maculata extract. The recommended parameters for producing Dactylorhiza maculata extract were determined: temperature 60 °C, process duration 60 min, hydro module 1:10. It is recommended to carry out the extraction using an aqueous ethyl alcohol solution with a mass fraction of the parent substance of 70%. It was found that such biologically active substances as rutin, quercetin, 3,3′,4′,5,5′,7-hexahydroxyflavonone, 3,3′,4′,5,5′,7-hexahydroxyflavonone-3-O-glycoside, gallic acid, and ferulic acid were dominant in Dactylorhiza maculata. A high phosphorus content was noted (2410.8 mg/kg dry matter). The studied Dactylorhizamaculata samples contained a large number of organic acids and water-soluble vitamins. The tested extracts were safe in terms of the content of heavy metals, pesticides, aflatoxin B1, and radionuclides, as well as pathogenic and opportunistic microorganisms; the content was significantly lower than the threshold limit values. The studied complex of biologically active substances from Dactylorhiza maculata extract samples had antimicrobial properties. It was found that the antioxidant activity of the samples was 217.89 ± 10.89 mg AA/g (AA—ascorbic acid). The high content of bioactive substances and the antimicrobial and antioxidant properties of Dactylorhizamaculata extract samples determine the application potential of this plant as a substitute for growth stimulants and feed antibiotics in the production of feed additives, aiming to increase the physiological and immune status of livestock and poultry.
New Insight into Taxonomy of European Mountain Pines, Pinus mugo Complex, Based on Complete Chloroplast Genomes Sequencing
Authors: Sokołowska Joanna , Fuchs Hanna , Celiński Konrad
Published: June 2021

The Pinus mugo complex is a large group of closely related mountain pines, which are an important component of the ecosystems of the most important mountain ranges, such as the Alps, Carpathians and Pyrenees. The phylogenetic relationships between taxa in this complex have been under discussion for many years. Despite the use of many different approaches, they still need to be clarified and supplemented with new data, especially those obtained with high-throughput methods. Therefore, in this study, the complete sequences of the chloroplast genomes of the three most recognized members of the Pinus mugo complex, i.e., Pinus mugo, Pinus rotundata and Pinus uncinata, were sequenced and analyzed to gain new insight into their phylogenetic relationships. Comparative analysis of their complete chloroplast genome sequences revealed several mutational hotspots potentially useful for the genetic identification of taxa from the Pinus mugo complex. Phylogenetic inference based on sixteen complete chloroplast genomes of different coniferous representatives showed that pines from the Pinus mugo complex form one distinct monophyletic group. The results obtained in this study provide new and valuable omics data for further research within the European mountain pine complex. They also indicate which regions may be useful in the search for diagnostic DNA markers for the members of Pinus mugo complex and set the baseline in the conservation of genetic resources of its endangered taxa.
Fruit Growth Stage Transitions in Two Mango Cultivars Grown in a Mediterranean Environment
Authors: Carella Alessandro , Gianguzzi Giuseppe , Scalisi Alessio , Farina Vittorio , Inglese Paolo , Bianco Riccardo Lo
Published: June 2021

Studying mango (Mangifera indica L.) fruit development represents one of the most important aspects for the precise orchard management under non-native environmental conditions. In this work, precision fruit gauges were used to investigate important eco-physiological aspects of fruit growth in two mango cultivars, Keitt (late ripening) and Tommy Atkins (early-mid ripening). Fruit absolute growth rate (AGR, mm day−1), daily diameter fluctuation (ΔD, mm), and a development index given by their ratio (AGR/ΔD) were monitored to identify the prevalent mechanism (cell division, cell expansion, ripening) involved in fruit development in three (‘Tommy Atkins’) or four (‘Keitt’) different periods during growth. In ‘Keitt’, cell division prevailed over cell expansion from 58 to 64 days after full bloom (DAFB), while the opposite occurred from 74 to 85 DAFB. Starting at 100 DAFB, internal changes prevailed over fruit growth, indicating the beginning of the ripening stage. In Tommy Atkins (an early ripening cultivar), no significant differences in AGR/ΔD was found among monitoring periods, indicating that both cell division and expansion coexisted at gradually decreasing rates until fruit harvest. To evaluate the effect of microclimate on fruit growth the relationship between vapor pressure deficit (VPD) and ΔD was also studied. In ‘Keitt’, VPD was the main driving force determining fruit diameter fluctuations. In ‘Tommy Atkins’, the lack of relationship between VPD and ΔD suggest a hydric isolation of the fruit due to the disruption of xylem and stomatal flows starting at 65 DAFB. Further studies are needed to confirm this hypothesis.
Effect of Rhizophagus irregularis on Growth and Quality of Cannabis sativa Seedlings
Authors: Kakabouki Ioanna , Mavroeidis Antonios , Tataridas Alexandros , Kousta Angeliki , Efthimiadou Aspasia , Karydogianni Stella , Katsenios Nikolaos , Roussis Ioannis , Papastylianou Panayiota
Published: June 2021

Rhizophagus irregularis is an arbuscular mycorrhiza fungus that can enhance plant nutrition and reduce transplant shock on seedlings. The present study aims to evaluate the effects of this fungus on the quality of cannabis (Cannabis sativa L.) seedlings. A greenhouse float system experiment was conducted in a completely randomized design with three treatments. The treatments included the application of 40, 80 and 120 fungus spores per L of nutrient solution (AMF1, AMF2 and AMF3, respectively). The evaluation was performed based on the agronomic characteristics of the seedlings (root and stem length and weight, stem diameter), N and P content, survival rate, and the Dickson’s quality index (DQI). Results indicated that root length and stem dry weight were significantly increased (by 34.14% and 21.4%, respectively) in the AMF3 treatment. The biomass of the seedlings’ roots, the fresh weight and the N content were not affected by the AMF. On the contrary, survival rate, P content and DQI were significantly increased in AMF3 (by 5%, 24.3% and 12.4% respectively). Overall, our findings suggest that the application of high doses of Rhizophagus irregularis (AMF3) on float system-produced cannabis seedlings results in a considerable increment of their quality.
Cassia fistula Leaves; UHPLC-QTOF-MS/MS Based Metabolite Profiling and Molecular Docking Insights to Explore Bioactives Role towards Inhibition of Pancreatic Lipase
Authors: Aabideen Zain Ul , Mumtaz Muhammad Waseem , Akhtar Muhammad Tayyab , Raza Muhammad Asam , Mukhtar Hamid , Irfan Ahmad , Raza Syed Ali , Touqeer Tooba , Nadeem Muhammad , Saari Nazamid
Published: June 2021

The present work was aimed at investigating hydroethanolic leaf extracts of Cassia fistula for their antioxidant and pancreatic lipase (PL) enzyme inhibitory properties. The most active extract was selected to profile the phytoconstituents by UHPLC-QTOF-MS/MS technique. Among the tested extracts, the 80% hydroethanolic extract exhibited the maximum levels of total phenolic and flavonoid contents (TPC and TFC) with a contribution of 201.3 ± 2.6 mg of gallic acid equivalent per gram of extract (GAE/g extract), and 116.3 ± 2.4 mg of rutin equivalent per gram of extract (RE/g extract), respectively. The same extract also showed promising 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and PL inhibitory activity with an IC50 (half maximal inhibitory concentration) of 30.5 ± 2.8 µg/mL and 17.31 ± 1.18 μg/mL, respectively. The phytochemical profiling of 80% hydroethanolic extract confirmed the presence of 23 metabolites of immense medicinal significance. Docking studies were conducted to investigate the potential interactions of compounds identified in the study. The docking study-based binding energy data and the interaction scheme both revealed the possible role of the identified compounds towards PL inhibitor. Moreover, energies of frontier molecular orbitals (FMOs), ionization potentials (IP), electron affinities (EA) and molecular electrostatic potentials (MEP) were also explored. The findings of the current work suggest that C. fistula is a promising natural source of antioxidant and antiobesity agents, which may be exploited to add pharmacological functionalities to food.
Genome-Wide Association Study for Ultraviolet-B Resistance in Soybean (Glycine max L.)
Authors: Lee Taeklim , Kim Kyung Do , Kim Ji-Min , Shin Ilseob , Heo Jinho , Jung Jiyeong , Lee Juseok , Moon Jung-Kyung , Kang Sungteag
Published: June 2021

The depletion of the stratospheric ozone layer is a major environmental issue and has increased the dosage of ultraviolet-B (UV-B) radiation reaching the Earth’s surface. Organisms are negatively affected by enhanced UV-B radiation, and especially in crop plants this may lead to severe yield losses. Soybean (Glycine max L.), a major legume crop, is sensitive to UV-B radiation, and therefore, it is required to breed the UV-B-resistant soybean cultivar. In this study, 688 soybean germplasms were phenotyped for two categories, Damage of Leaf Chlorosis (DLC) and Damage of Leaf Shape (DLS), after supplementary UV-B irradiation for 14 days. About 5% of the germplasms showed strong UV-B resistance, and GCS731 was the most resistant genotype. Their phenotypic distributions showed similar patterns to the normal, suggesting UV-B resistance as a quantitative trait governed by polygenes. A total of 688 soybean germplasms were genotyped using the Axiom® Soya 180K SNP array, and a genome-wide association study (GWAS) was conducted to identify SNPs significantly associated with the two traits, DLC and DLS. Five peaks on chromosomes 2, 6, 10, and 11 were significantly associated with either DLC or DLS, and the five adjacent genes were selected as candidate genes responsible for UV-B resistance. Among those candidate genes, Glyma.02g017500 and Glyma.06g103200 encode cryptochrome (CRY) and cryptochrome 1 (CRY1), respectively, and are known to play a role in DNA repair during photoreactivation. Real-time quantitative RT-PCR (qRT-PCR) results revealed that CRY1 was expressed significantly higher in the UV-B-resistant soybean compared to the susceptible soybean after 6 h of UV-B irradiation. This study is the first GWAS report on UV-B resistance in soybean, and the results will provide valuable information for breeding UV-B-resistant soybeans in preparation for climate change.
Effect of the Combination of Levofloxacin with Cationic Carbosilane Dendron and Peptide in the Prevention and Treatment of Staphylococcus aureus Biofilms
Authors: Fernandez Jael , Martin-Serrano Ángela , Gómez-Casanova Natalia , Falanga Annarita , Galdiero Stefania , Javier de la Mata Francisco , Heredero-Bermejo Irene , Ortega Paula
Published: June 2021

Antibiotic resistance and biofilm-related infections, persistent in conventional antimicrobial treatment, are continuously increasing and represent a major health problem worldwide. Therefore, the development of new effective treatments to prevent and treat biofilm-related infections represents a crucial challenge. Unfortunately, the extensive use of antibiotics has led to an increase of resistant bacteria with the subsequent loss of effectivity of commercial antibiotics, mainly due to antibiotic resistance and the ability of some bacteria to form microbial communities in biotic or abiotic surfaces (biofilms). In some cases, these biofilms are resistant to high concentrations of antibiotics that lead to treatment failure and recurrence of the associated infections. In the fight against microbial resistance, the combination of traditional antibiotics with new compounds (combination therapy) is an alternative that is becoming more extensive in the medical field. In this work, we studied the cooperative effects between levofloxacin, an approved antibiotic, and peptides or cationic dendritic molecules, compounds that are emerging as a feasible solution to overcome the problem of microbial resistance caused by pathogenic biofilms. We studied a new therapeutic approach that involves the use of levofloxacin in combination with a cationic carbosilane dendron, called MalG2(SNHMe2Cl)4, or a synthetic cell-penetrating peptide, called gH625, conjugated to the aforementioned dendron. To carry out the study, we used two combinations (1) levofloxacin/dendron and (2) levofloxacin/dendron-peptide nanoconjugate. The results showed the synergistic effect of the combination therapy to treat Staphylococcus aureus biofilms. In addition, we generated a fluorescein labeled peptide that allowed us to observe the conjugate (dendron-peptide) localization throughout the bacterial biofilm by confocal laser scanning microscopy.
Antifibrotic Effect of Bletilla striata Polysaccharide-Resveratrol-Impregnated Dual-Layer Carboxymethyl Cellulose-Based Sponge for The Prevention of Epidural Fibrosis after Laminectomy
Authors: Chen Hsuan-Yu , Lin Tzu-Chieh , Chiang Chih-Yung , Wey Shiuan-Li , Lin Feng-Huei , Yang Kai-Chiang , Chang Chih-Hao , Hu Ming-Hsiao
Published: June 2021

The application of antifibrotic materials can alleviate epidural fibrosis by restricting excessive fibroblast proliferation and mitigating scar tissue formation. Here, a biodegradable carboxymethyl cellulose (CMC)-Bletilla striata polysaccharide (BSP)-resveratrol (RES) sponge was fabricated to inhibit scar tissue formation post laminectomy surgery. Fibroblasts NIH/3T3, myoblasts C2C12, neural cells PC-12, and Schwann cells RSC96 were used to evaluate the in vitro cytocompatibility. Laminectomies on 10 Sprague–Dawley rats with/without the application of the CMC-BSP-RES sponge were performed. The severity of adhesion between the dura mater and formed scar tissue was qualitatively scored. All cell lines exhibited good viability with no significant difference in cytotoxicity when cultured with variable extractions of the CMC-BSP-RES sponge. S100a4 and P4hb expressions were downregulated in NIH/3T3 cultured in the CMC-BSP-RES sponge, implying that this sponge potentially inhibits fibroblast activity. No post-operative shrinkage or dura mater expansion along the surgical site was detected. The peel-off tests revealed that the tenacity of adhesion de-creased. Histopathological examinations verified that the average number of fibroblasts in the CMC-BSP-RES group considerably decreased. The CMC-BSP-RES sponge is a biocompatible and effective material for alleviating post-operative epidural fibrosis and mitigating fibroblast expression following laminectomy.
Electrical Supply Circuit for a Cold Plasma Source at Atmospheric Pressure Based on a Voltage Multiplier
Authors: Stoican Ovidiu S.
Published: June 2021

A cold plasma source operating at atmospheric pressure powered by a voltage multiplier is reported. In addition to its usual high voltage output, there is an intermediate output of lower voltage and higher current capability. A discharge current is drawn from both outputs. The ratio of the current supplied by each output depends on the operating state, namely, before or after the plasma jet formation. The electrical circuit is equivalent to two dc sources connected in parallel, used to initiate and sustain the electrical discharge. The plasma source is aimed to study the effect of cold plasma on the surface of various liquid or solid materials, including polymers.
Nanocomposites Materials of PLA Reinforced with Nanoclays Using a Masterbatch Technology: A Study of the Mechanical Performance and Its Sustainability
Authors: Oliver-Ortega Helena , Tresserras Josep , Julian Fernando , Alcalà Manel , Bala Alba , Espinach Francesc Xavier , Méndez José Alberto
Published: June 2021

Packaging consumes around 40% of the total plastic production. One of the most important fields with high requirements is food packaging. Food packaging products have been commonly produced with petrol polymers, but due to environmental concerns, the market is being moved to biopolymers. Poly (lactic acid) (PLA) is the most promising biopolymer, as it is bio-based and biodegradable, and it is well established in the market. Nonetheless, its barrier properties need to be enhanced to be competitive with other polymers such as polyethylene terephthalate (PET). Nanoclays improve the barrier properties of polymeric materials if correct dispersion and exfoliation are obtained. Thus, it marks a milestone to obtain an appropriate dispersion. A predispersed methodology is proposed as a compounding process to improve the dispersion of these composites instead of common melt procedures. Afterwards, the effect of the polarity of the matrix was analyzing using polar and surface modified nanoclays with contents ranging from 2 to 8% w/w. The results showed the suitability of the predispersed and concentrated compound, technically named masterbatch, to obtain intercalated structures and the higher dispersion of polar nanoclays. Finally, the mechanical performance and sustainability of the prepared materials were simulated in a food tray, showing the best assessment of these materials and their lower fingerprint.
Halloysite Nanotubes and Silane-Treated Alumina Trihydrate Hybrid Flame Retardant System for High-Performance Cable Insulation
Authors: Paszkiewicz Sandra , Irska Izabela , Taraghi Iman , Piesowicz Elżbieta , Sieminski Jakub , Zawisza Karolina , Pypeć Krzysztof , Dobrzynska Renata , Terelak-Tymczyna Agnieszka , Stateczny Kamil , Szymczak Bartłomiej
Published: June 2021

The effect of the presence of halloysite nanotubes (HNTs) and silane-treated alumina trihydrate (ATH-sil) nanofillers on the mechanical, thermal, and flame retardancy properties of ethylene-vinyl acetate (EVA) copolymer/low-density polyethylene (LDPE) blends was investigated. Different weight percentages of HNT and ATH-sil nanoparticles, as well as the hybrid system of those nanofillers, were melt mixed with the polymer blend (reference sample) using a twin-screw extruder. The morphology of the nanoparticles and polymer compositions was studied using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The mechanical properties, hardness, water absorption, and melt flow index (MFI) of the compositions were assessed. The tensile strength increases as a function of the amount of HNT nanofiller; however, the elongation at break decreases. In the case of the hybrid system of nanofillers, the compositions showed superior mechanical properties. The thermal properties of the reference sample and those of the corresponding sample with nanofiller blends were studied using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Two peaks were observed in the melting and crystallization temperatures. This shows that the EVA/LDPE is an immiscible polymer blend. The thermal stability of the blends was improved by the presence of HNTs and ATH-sil nanoparticles. Thermal degradation temperatures were shifted to higher values by the presence of hybrid nanofillers. Finally, the flammability of the compositions was assessed. Flammability as reflected by the limiting oxygen index (OI) was increased by the presence of HNT and ATH-sil nanofiller and a hybrid system of the nanoparticles.
Utilization of Polymer Concrete Composites for a Circular Economy: A Comparative Review for Assessment of Recycling and Waste Utilization
Authors: Alhazmi Hatem , Shah Syyed Adnan Raheel , Anwar Muhammad Kashif , Raza Ali , Ullah Muhammad Kaleem , Iqbal Fahad
Published: June 2021

Polymer composites have been identified as the most innovative and selective materials known in the 21st century. Presently, polymer concrete composites (PCC) made from industrial or agricultural waste are becoming more popular as the demand for high-strength concrete for various applications is increasing. Polymer concrete composites not only provide high strength properties but also provide specific characteristics, such as high durability, decreased drying shrinkage, reduced permeability, and chemical or heat resistance. This paper provides a detailed review of the utilization of polymer composites in the construction industry based on the circular economy model. This paper provides an updated and detailed report on the effects of polymer composites in concrete as supplementary cementitious materials and a comprehensive analysis of the existing literature on their utilization and the production of polymer composites. A detailed review of a variety of polymers, their qualities, performance, and classification, and various polymer composite production methods is given to select the best polymer composite materials for specific applications. PCCs have become a promising alternative for the reuse of waste materials due to their exceptional performance. Based on the findings of the studies evaluated, it can be concluded that more research is needed to provide a foundation for a regulatory structure for the acceptance of polymer composites.
Recent Progress on Two-Dimensional Carbon Materials for Emerging Post-Lithium (Na+, K+, Zn2+) Hybrid Supercapacitors
Authors: Han Chao , Wang Xinyi , Peng Jian , Xia Qingbing , Chou Shulei , Cheng Gang , Huang Zhenguo , Li Weijie
Published: June 2021

The hybrid ion capacitor (HIC) is a hybrid electrochemical energy storage device that combines the intercalation mechanism of a lithium-ion battery anode with the double-layer mechanism of the cathode. Thus, an HIC combines the high energy density of batteries and the high power density of supercapacitors, thus bridging the gap between batteries and supercapacitors. Two-dimensional (2D) carbon materials (graphite, graphene, carbon nanosheets) are promising candidates for hybrid capacitors owing to their unique physical and chemical properties, including their enormous specific surface areas, abundance of active sites (surface and functional groups), and large interlayer spacing. So far, there has been no review focusing on the 2D carbon-based materials for the emerging post-lithium hybrid capacitors. This concept review considers the role of 2D carbon in hybrid capacitors and the recent progress in the application of 2D carbon materials for post-Li (Na+, K+, Zn2+) hybrid capacitors. Moreover, their challenges and trends in their future development are discussed.
A Comprehensive Investigation on 3D Printing of Polyamide 11 and Thermoplastic Polyurethane via Multi Jet Fusion
Authors: Tey Wei Shian , Cai Chao , Zhou Kun
Published: June 2021

Multi Jet Fusion (MJF) is a recently developed polymeric powder bed fusion (PBF) additive manufacturing technique that has received considerable attention in the industrial and scientific community due to its ability to fabricate functional and complex polymeric parts efficiently. In this work, a systematic characterization of the physicochemical properties of MJF-certified polyamide 11 (PA11) and thermoplastic polyurethane (TPU) powder was conducted. The mechanical performance and print quality of the specimens printed using both powders were then evaluated. Both PA11 and TPU powders showed irregular morphology with sharp features and had broad particle size distribution, but such features did not impair their printability significantly. According to the DSC scans, the PA11 specimen exhibited two endothermic peaks, while the TPU specimen exhibited a broad endothermic peak (116–150 °C). The PA11 specimens possessed the highest tensile strength in the Z orientation, as opposed to the TPU specimens which possessed the lowest tensile strength along the same orientation. The flexural properties of the PA11 and TPU specimens displayed a similar anisotropy where the flexural strength was highest in the Z orientation and lowest in the X orientation. The porosity values of both the PA11 and the TPU specimens were observed to be the lowest in the Z orientation and highest in the X orientation, which was the opposite of the trend observed for the flexural strength of the specimens. The PA11 specimen possessed a low coefficient of friction (COF) of 0.13 and wear rate of 8.68 × 10−5 mm3/Nm as compared to the TPU specimen, which had a COF of 0.55 and wear rate of 0.012 mm3/Nm. The PA11 specimens generally had lower roughness values on their surfaces (Ra < 25 μm), while the TPU specimens had much rougher surfaces (Ra > 40 μm). This investigation aims to uncover and explain phenomena that are unique to the MJF process of PA11 and TPU while also serving as a benchmark against similar polymeric parts printed using other PBF processes.
Enhancing the Fire Safety and Smoke Safety of Bio–Based Rigid Polyurethane Foam via Inserting a Reactive Flame Retardant Containing P@N and Blending Silica Aerogel Powder
Authors: Bo Guangxu , Xu Xiaoling , Tian Xiaoke , Wu Jiao , Yan Yunjun
Published: June 2021

Rigid polyurethane foams (RPUFs) are widely used in many fields, but they are easy to burn and produce a lot of smoke, which seriously endangers the safety of people’s lives and property. In this study, tetraethyl(1,5–bis(bis(2–hydroxypropyl)amino)pentane–1,5–diyl)bis(phosphonate) (TBPBP), as a phosphorus–nitrogen–containing reactive–type flame retardant, was successfully synthesized and employed to enhance the flame retardancy of RPUFs, and silica aerogel (SA) powder was utilized to reduce harmful fumes. Castor oil–based rigid polyurethane foam containing SA powder and TBPBP was named RPUF–T45@SA20. Compared with neat RPUF, the obtained RPUF–T45@SA20 greatly improved with the compressive strength properties and the LOI value increased by 93.64% and 44.27%, respectively, and reached the V–0 rank of UL–94 testing. The total heat release (THR) and total smoke production (TSP) of RPUF–T45@SA20 were, respectively, reduced by 44.66% and 51.89% compared to those of the neat RPUF. A possible flame–retardant mechanism of RPUF–T45@SA20 was also proposed. This study suggested that RPUF incorporated with TBPBP and SA powder is a prosperous potential composite for fire and smoke safety as a building insulation material.
Atomic Scale Mechanisms Controlling the Oxidation of Polyethylene: A First Principles Study
Authors: Ahn Yunho , Colin Xavier , Roma Guido
Published: June 2021

Understanding the degradation mechanisms of aliphatic polymers by thermal oxidation and radio-oxidation is very important in order to assess their lifetime in a variety of industrial applications. We focus here on polyethylene as a prototypical aliphatic polymer. Kinetic models describing the time evolution of the concentration of chain defects and radicals species in the material identify a relevant step in the formation and subsequent decomposition of transient hydroperoxides species, finally leading to carbonyl defects, in particular ketones. In this paper, we first summarize the most relevant mechanistic paths proposed in the literature for hydroperoxide formation and decomposition and, second, revisit them using first principles calculations based on Density Functional Theory (DFT). Our results partially confirm commonly accepted reaction energies, but also propose alternative, more favourable, reaction paths. We highlight the influence of the environment—crystalline or not—on the outcome of some of the studied chemical reactions. A remarkable result of our calculations is that hydroxyl radicals play an important role in the decomposition of hydroperoxides. Based on our findings, it should be possible to improve the set of equations and parameters used in current kinetic simulations of polyethylene radio-oxidation.
Preparation of Bamboo-Like Carbon Nanotube Loaded Piezoresistive Polyurethane-Silicone Rubber Composite
Authors: Nabeel Mohammed , Varga Miklós , Kuzsela László , Filep Ádám , Fiser Béla , Viskolcz Béla , Kollar Mariann , Vanyorek László
Published: June 2021

In this study, a novel technology is reported to prepare a piezoresistive polyurethane-silicone rubber nanocomposite. Polyurethane (PU) foam was loaded with a nitrogen-doped bamboo-shaped carbon nanotube (N-BCNT) by using dip-coating, and then, impregnated with silicone rubber. PU was used as a supporting substrate for N-BCNT, while silicone rubber was applied to fill the pores of the foam to improve recoverability, compressive strength, and durability. The composite displays good electrical conductivity, short response time, and excellent repeatability. The resistance was reduced when the amount of N-BCNT (0.43 wt %) was increased due to the expanded conductive path for electron transport. The piezoresistive composite has been successfully tested in many applications, such as human monitoring and finger touch detection.
Iron Based Chitin Composite Films for Efficient Solar Seawater Desalination
Authors: Zhang Rumeng , Li Xin , Xie Haiquan , Yao Lunguang , Ye Liqun
Published: June 2021

Seawater desalination provides a convenient method for the sustainable production of fresh water. However, the preparation of low-cost, high-efficiency solar absorbers remains a huge challenge. To this end, our research group designed and produced a cheap absorber—a membrane made of natural polymer chitin with black FeS and Fe3O4, respectively. Due to the hierarchical pore structure, excellent photothermal performance and good hydrophilicity of the film, their water evaporation rates reached 1.47 kg/m2/h and 1.55 kg/m2/h under one sunlight, respectively. Under about 10 suns, the highest desalination efficiency of FeS/chitin and Fe3O4/chitin are 90% and 74%, respectively, and their salinities are also in line with the World Health Organization drinking water standards. These results indicate the potential of chitin-based nanomaterials as high-efficiency solar absorbers to produce fresh water.
Problematising the Official Athens Mosque: Between Mere Place of Worship and 21st Century ‘Trojan Horse’
Authors: Verousi Christina , Allen Chris
Published: June 2021

This article investigates the ‘problematisation’ of the recently inaugurated mosque in the city of Athens, the capital’s first ‘official’ mosque since the country was liberated from the Ottoman Empire almost two centuries ago. Building on and developing the existing scholarly literature on the problematisation of mosques in the contemporary European setting, this article generates new knowledge by focusing on the Greco-specific context of that same problematisation: an amalgam of history, geography, religion and culture, that asymmetrically shape and inform how and why the new Athens mosque is—and indeed continues to be—a site of conflict and opposition. Presenting new empirical data, this article uses an innovative and original approach to bring together two separate pieces of fieldwork undertaken first-hand by the authors in 2001/2 and 2019/20. Analysing the two sets of data, a threefold thematic structure is employed that focuses on Greece’s history, Christian Orthodoxy and global terrorism. This article first explores the existing scholarly canon relating to the contemporary problematisation of mosques through a focused overview of Greece’s history, religion and culture appropriate to mosques and in part, Muslims and Islam. From there it sets out the findings from the two periods of fieldwork to illustrate and evidence discourses of opposition towards the mosque and how these serve to function both symbolically and tangibly. Using the thematic analysis, theories relating to the ideological processes of Islamophobia are deployed to elucidate a better understanding of the Athens mosque. In doing so, this article makes a timely contribution.
Arctic-Boreal Lake Phenology Shows a Relationship between Earlier Lake Ice-Out and Later Green-Up
Authors: Kuhn Catherine , John Aji , Hille Ris Lambers Janneke , Butman David , Tan Amanda
Published: June 2021

Satellite remote sensing has transformed our understanding of Earth processes. One component of the Earth system where large uncertainties remain are Arctic and boreal freshwater lakes. With only short periods of open water due to annual ice cover, lake productivity in these regions is extremely sensitive to warming induced changes in ice cover. At the same time, productivity dynamics in these lakes vary enormously, even over short distances, making it difficult to understand these potential changes. A major impediment to an improved understanding of lake dynamics has been sparsely distributed field measurements, in large part due to the complexity and expense of conducting scientific research in remote northern latitudes. This project overcomes that hurdle by using a new set of ‘eyes in the sky’, the Planet Labs CubeSat fleet, to observe 35 lakes across 3 different arctic-boreal ecoregions in western North America. We extract time series of lake reflectance to identify ice-out and green-up across three years (2017–2019). We find that lakes with later ice-out have significantly faster green-ups. Our results also show ice-out varies latitudinally by 38 days from south to north, but only varies across years by ~9 days. In contrast, green-up varied between years by 22 days in addition to showing significant spatial variability. We compare PlanetScope to Sentinel-2 data and independently validate our ice-out estimates, finding an ice-out mean absolute difference (MAD) ~9 days. This study demonstrates the potential of using CubeSat imagery to monitor the timing and magnitude of ice-off and green-up at high spatiotemporal resolution.
Integration of Satellite InSAR with a Wireless Network of Geotechnical Sensors for Slope Monitoring in Urban Areas: The Pariana Landslide Case (Massa, Italy)
Authors: Ciampalini Andrea , Farina Paolo , Lombardi Luca , Nocentini Massimiliano , Taurino Veronica , Guidi Roberto , Pina Fernando della , Tavarini Davide
Published: June 2021

Slow to extremely slow landslides in urban areas may cause severe damage to buildings and infrastructure that can lead to the evacuation of local populations in case of slope accelerations. Monitoring the spatial and temporal evolution of this type of natural hazard represents a major concern for the public authorities in charge of risk management. Pariana, a village with 400 residents located in the Apuan Alps (Massa, Tuscany, Italy), is an example of urban settlement where the population has long been forced to live with considerable slope instability. In the last 30 years, due to the slope movements associated with a slow-moving landslide that has affected a significant portion of the built-up area, several buildings have been damaged, including a school and the provincial road crossing the unstable area, leading to the need for an installation of a slope monitoring system with early warning capabilities, in parallel with the implementation of mitigation works. In this paper, we show how satellite multi-temporal interferometric synthetic aperture radar (MT-InSAR) data can be effectively used when coupled with a wireless sensor network made of several bar extensometers and a borehole inclinometer. In fact, thanks to their wide area coverage and opportunistic nature, satellite InSAR data allow one to clearly identify the spatial distribution of surface movements and their long-term temporal evolution. On the other hand, geotechnical sensors installed on specific elements at risk (e.g., private buildings, retaining walls, etc.), and collected through Wi-Fi dataloggers, provide near real-time data that can be used to identify sudden accelerations in slope movements, subsequently triggering alarms. The integration of those two-monitoring systems has been tested and assessed in Pariana. Results show how a hybrid slope monitoring program based on the two different technologies can be used to effectively monitor slow-moving landslides and to identify sudden accelerations and activate a response plan.
Trends for the Future of Education Programs for Professional Development
Authors: Ramírez-Montoya María Soledad , Andrade-Vargas Lucy , Rivera-Rogel Diana , Portuguez-Castro May
Published: June 2021

Scientific and technological developments bring new requirements for university education and, particularly, the training of education professionals. There is a regular need to update curricula to integrate market trends and educational approaches. It is necessary to know future trends in education and teaching programs. Our research in a higher education institution in Ecuador focused on providing perspectives on the future of educational programs by analyzing trends in educational programs’ designs, students and professors’ needs for innovative education. We used the descriptive/exploratory case study method, employing quantitative surveys and qualitative interviews, focus groups and benchmarking as instruments. The surveys were applied to 337 current students, 384 potential students and 313 graduates of Educational Sciences. We conducted interviews with 20 experts from Mexico, Spain, Colombia and Ecuador. We held focus groups with 32 education professionals, including rectors, principals, educational specialists and primary, secondary and university teachers. Benchmarking was used in our analysis of ten universities. The results focused on five elements that were units of analysis (1) characteristics of education programs, (2) student requirements, (3) required educational modalities, (4) trends in education and (5) future of education programs. The data and results may be of interest to decision-makers, academicians, researchers, students and citizens interested in professional education and other disciplinary areas.
Socio-Environmental Impacts of the Avocado Boom in the Meseta Purépecha, Michoacán, Mexico
Authors: De la Vega-Rivera Alfonso , Merino-Pérez Leticia
Published: June 2021

The rapid expansion of avocado orchards in the Meseta Purépecha, in the state of Michoacán in central Mexico, has mostly been driven by the increasing demand of North American consumers in the context of the North American Free Trade Agreement (NAFTA). While the cultivation of avocado has produced regional economic growth, economic profits are strongly concentrated, notably in the hands of American agribusiness, while its regional and local environmental impacts increasingly affect indigenous and rural communities, the most vulnerable groups in that region. Our work describes the diverse impacts of avocado industrial production on local livelihoods, communal rights, and public health and also reviews the policies and incentives that have favored avocado expansion in the Purépecha region. We compared the land-use change and socio-ecological deterioration associated with avocado expansion in the majority of the Meseta with the indigenous community of San Juan Nuevo Parangaricutiro also in that region, where strong community institutions have enabled San Juan to limit avocado expansion and maintain the communal forests.
Effects of Agricultural Programmes and Land Ownership on the Adoption of Sustainable Agricultural Practices in Nigeria
Authors: Adesida Ireti Emmanuel , Nkomoki William , Bavorova Miroslava , Madaki Mustapha Yakubu
Published: June 2021

Many countries promote food security through agricultural policies to boost agricultural productivity without looking at the effect of such policies on sustainability. This study investigates the effect of agricultural policies and land ownership on the adoption of sustainable agricultural practices in Nigeria. A structured questionnaire was used for data collection from a survey of 288 smallholder farmers in November 2018. The results of the Logistic Regression Model revealed that programs affected the adoption of SAP. Farmers that participated in E-wallet were more likely to adopt fertiliser trees and use animal manure and were less likely to adopt planting basins than non-users. Farmers who participated in Fadama were less likely to adopt crop diversification. Participation in Farmers’ Field School (FFS) contributed to a greater likelihood of farmers adopting crop diversification and cover crops. Landowner farmers were found to be more likely to adopt mulching and less likely to adopt fertiliser trees. This study provides practical implications to foster sustainability through effective agricultural policies and land ownership to facilitate sustainable agricultural practice adoption rates.
Impact of Passive Energy Efficiency Measures on Cooling Energy Demand in an Architectural Campus Building in Karachi, Pakistan
Authors: Bughio Mushk , Khan Muhammad Shoaib , Mahar Waqas Ahmed , Schuetze Thorsten
Published: June 2021

Electric appliances for cooling and lighting are responsible for most of the increase in electricity consumption in Karachi, Pakistan. This study aims to investigate the impact of passive energy efficiency measures (PEEMs) on the potential reduction of indoor temperature and cooling energy demand of an architectural campus building (ACB) in Karachi, Pakistan. PEEMs focus on the building envelope’s design and construction, which is a key factor of influence on a building’s cooling energy demand. The existing architectural campus building was modeled using the building information modeling (BIM) software Autodesk Revit. Data related to the electricity consumption for cooling, building masses, occupancy conditions, utility bills, energy use intensity, as well as space types, were collected and analyzed to develop a virtual ACB model. The utility bill data were used to calibrate the DesignBuilder and EnergyPlus base case models of the existing ACB. The cooling energy demand was compared with different alternative building envelope compositions applied as PEEMs in the renovation of the existing exemplary ACB. Finally, cooling energy demand reduction potentials and the related potential electricity demand savings were determined. The quantification of the cooling energy demand facilitates the definition of the building’s electricity consumption benchmarks for cooling with specific technologies.
African Lives Matter: Wild Food Plants Matter for Livelihoods, Justice, and the Environment—A Policy Brief for Agricultural Reform and New Crops
Authors: Leakey Roger , Mabhaudhi Tafadzwanashe , Gurib-Fakim Ameenah
Published: June 2021

International agricultural policies to address hunger and malnutrition in the tropics and sub-tropics have typically been based on approaches to the intensification of farming systems effective in industrialised economies where the social, economic, and environmental conditions and the infrastructure are very different to those in Africa. The consequence of this short-sightedness has been that agricultural productivity, dependent on ecosystem services from natural capital, has declined in Africa due to ecological and environmental collapse. This has undermined the livelihoods of the millions of smallholder farmers living on the brink of the cash economy, leading to severe social injustice. This review summarises advances in smallholder agriculture’s sustainable intensification in the tropics and sub-tropics, leveraging the domestication and commercialisation of wild indigenous tree species that produce nutritious, marketable, and useful food and non-food products. These are grown within diversified and multifunctional farming systems together with conventional food staples and local orphan crops to reduce land degradation, pollution, water extraction, and nutrient mining while promoting services such as pollination and other ecological functions. The benefits arising from this approach simultaneously address hunger, malnutrition, poverty, social injustice, and a stagnant economy, as well as important global issues such as climate change, loss of biodiversity and environmental degradation. Addressing these issues may also reduce the risk of future pandemics of zoonotic diseases, such as COVID-19. This set of serious global issues epitomise our divided and dysfunctional world and calls out for action. Enhancing sustainable smallholder productivity using indigenous and wild foods is an important international policy and business intervention, vital for achieving the 2030 Sustainable Development Goals and the rebalancing of the global economy by restoring natural capital within new African indigenous food industries.
Overview and Exploitation of Haptic Tele-Weight Device in Virtual Shopping Stores
Authors: Farooq Aqeel , Seyedmahmoudian Mehdi , Horan Ben , Mekhilef Saad , Stojcevski Alex
Published: June 2021

In view of the problem of e-commerce scams and the absence of haptic interaction, this research aims to introduce and create a tele-weight device for e-commerce shopping in smart cities. The objective is to use the proposed prototype to provide a brief overview of the possible technological advancements. When the tele-weight device is affixed over the head-mounted display, it allows the user to feel the item’s weight while shopping in the virtual store. Addressing the problem of having no physical interaction between the user (player) and a series game scene in virtual reality (VR) headsets, this research approach focuses on creating a prototype device that has two parts, a sending part and a receiving part. The sending part measures the weight of the object and transmits it over the cellular network to the receiver side. The virtual store user at the receiving side can thus realize the weight of the ordered object. The findings from this work include a visual display of the item’s weight to the virtual store e-commerce user. By introducing sustainability, this haptic technology-assisted technique can help the customer realize the weight of an object and thus have a better immersive experience. In the device, the load cell measures the weight of the object and amplifies it using the HX711 amplifier. However, some delay in the demonstration of the weight was observed during experimentation, and this indirectly altered the performance of the system. One set of the device is sited at the virtual store user premises while the sending end of the device is positioned at the warehouse. The sending end hardware includes an Arduino Uno device, an HX711 amplifier chip to amplify the weight from the load cell, and a cellular module (Sim900A chip-based) to transmit the weight in the form of an encoded message. The receiving end hardware includes a cellular module and an actuator involving a motor gear arrangement to demonstrate the weight of the object. Combining the fields of e-commerce, embedded systems, VR, and haptic sensing, this research can help create a more secure marketplace to attain a higher level of customer satisfaction.