bluuebunny/crossref_metadata_2025 huggingface dataset:
A Thousand Words Express a Common Idea? Understanding International Tourists’ Reviews of Mt. Huangshan, China, through a Deep Learning Approach
Authors: Chai Cheng , Song Yao , Qin Zhenzhen
Published: May 2021

Tourists’ experiential perceptions and specific behaviors are of importance to facilitate geographers’ and planners’ understanding of landscape surroundings. In addition, the potentially significant role of online user generated content (UGC) in tourism landscape research has only received limited attention, especially in the era of artificial intelligence. The motivation of the present study is to understand international tourists’ online reviews of Mt. Huangshan in China. Through a state-of-the-art natural language processing network (BERT) analyzing posted reviews across international tourists, our results facilitate relevant landscape development and design decisions. Second, the proposed analytic method can be an exemplified model to inspire relevant landscape planners and decision-makers to conduct future researches. Through the clustering results, several key topics are revealed, including international tourists’ perceptual image of Mt. Huangshan, tour route planning, and negative experience of staying.
Restoration and Conservation of Priority Areas of Caatinga’s Semi-Arid Forest Remnants Can Support Connectivity within an Agricultural Landscape
Authors: Salazar Andrés A. , Arellano Eduardo C. , Muñoz-Sáez Andrés , Miranda Marcelo D. , Oliveira da Silva Fabiana , Zielonka Natalia B. , Crowther Liam P. , Silva-Ferreira Vinina , Oliveira-Reboucas Patricia , Dicks Lynn V.
Published: May 2021

Land-use and land-cover (LULC) changes are major drivers of biodiversity loss in semi-arid regions, such as the Caatinga biome located in the Northeast of Brazil. We investigated landscape dynamics and fragmentation in an area of the São Francisco Valley in the Brazilian Caatinga biome and measured the effect of these dynamics on ecological, functional and structural connectivity over a 33-year period (1985–2018). We calculated landscape connectivity indices based on graph theory to quantify the effect of further agricultural expansion on ecological connectivity at the landscape scale. We used a multicriteria decision analysis that integrates graph-based connectivity indices at the habitat patch scale, combined with an index of human disturbance to identify patches that, if conserved and restored, preserve the connectivity of the landscape most effectively. In the period studied, agriculture increased at a rate of 2104 ha/year, while native Caatinga vegetation decreased at a rate of 5203 ha/year. Both dense and open Caatinga became more fragmented, with the number of fragments increasing by 85.2% and 28.6%, respectively, whilst the average fragment size decreased by 84.8% and 6.1% for dense and open Caatinga, respectively. If agriculture patches were to expand by a 300 m buffer around each patch, the overall ecological connectivity could be reduced by 6–15%, depending on the species’ (small- to mid-size terrestrial vertebrates) mobility characteristics for which the connectivity indices were calculated. We provided explicit spatial connectivity and fragmentation information for the conservation and restoration of the Caatinga vegetation in the studied area. This information helps with conservation planning in this rapidly changing ecosystem.
Strategies for the Production of Soluble Interferon-Alpha Consensus and Potential Application in Arboviruses and SARS-CoV-2
Authors: Grabarz Felipe , Lopes Alexandre Paulo Yague , Barbosa Flávia Ferreira , Barazzone Giovana Cappio , Santos Jademilson Celestino , Botosso Viviane Fongaro , Jorge Soraia Attie Calil , Nascimento Ana Lucia Tabet Oller , Astray Renato Mancini , Gonçalves Viviane Maimoni
Published: May 2021

Biopharmaceutical production is currently a multibillion-dollar industry with high growth perspectives. The research and development of biologically sourced pharmaceuticals are extremely important and a reality in our current healthcare system. Interferon alpha consensus (cIFN) is a non-natural synthetic antiviral molecule that comprises all the most prevalent amino acids of IFN-α into one consensus protein sequence. For clinical use, cIFN is produced in E. coli in the form of inclusion bodies. Here, we describe the use of two solubility tags (Fh8 and DsbC) to improve soluble cIFN production. Furthermore, we analyzed cIFN production in different culture media and temperatures in order to improve biopharmaceutical production. Our results demonstrate that Fh8-cIFN yield was improved when bacteria were cultivated in autoinduction culture medium at 30 °C. After hydrolysis, the recovery of soluble untagged cIFN was 58% from purified Fh8-cIFN molecule, fourfold higher when compared to cIFN recovered from the DsbC-cIFN, which achieved 14% recovery. The biological activity of cIFN was tested on in vitro model of antiviral effect against Zika, Mayaro, Chikungunya and SARS-CoV-2 virus infection in susceptible VERO cells. We show, for the first time, that cIFN has a potent activity against these viruses, being very low amounts of the molecule sufficient to inhibit virus multiplication. Thus, this molecule could be used in a clinical approach to treat Arboviruses and SARS-CoV-2.
Anti-Cancer and Immunomodulatory Activity of a Polyethylene Glycol-Betulinic Acid Conjugate on Pancreatic Cancer Cells
Authors: Fru Pascaline Nanga , Nweke Ekene Emmanuel , Mthimkhulu Nompumelelo , Mvango Sindisiwe , Nel Marietha , Pilcher Lynne Alison , Balogun Mohammed
Published: May 2021

Drug delivery systems involving polymer therapeutics enhance drug potency by improved solubility and specificity and may assist in circumventing chemoresistance in pancreatic cancer (PC). We compared the effectiveness of the naturally occurring drug, betulinic acid (BA), alone and in a polymer conjugate construct of polyethylene glycol (PEG), (PEG–BA), on PC cells (MIA PaCa-2), a normal cell line (Vero) and on peripheral blood mononuclear cells (PBMCs). PEG–BA, was tested for its effect on cell death, immunomodulation and chemoresistance-linked signalling pathways. The conjugate was significantly more toxic to PC cells (p < 0.001, IC50 of 1.35 ± 0.11 µM) compared to BA (IC50 of 12.70 ± 0.34 µM), with a selectivity index (SI) of 7.28 compared to 1.4 in Vero cells. Cytotoxicity was confirmed by increased apoptotic cell death. PEG–BA inhibited the production of IL-6 by 4–5.5 fold compared to BA-treated cells. Furthermore, PEG–BA treatment of MIA PaCa-2 cells resulted in the dysregulation of crucial chemoresistance genes such as WNT3A, TXNRD1, SLC2A1 and GATA3. The dysregulation of chemoresistance-associated genes and the inhibition of cytokines such as IL-6 by the model polymer construct, PEG–BA, holds promise for further exploration in PC treatment.
Antiretroviral Therapy Improves Acquired Immunodeficiency Syndrome with Systemic Lupus Erythematosus
Authors: Okada Akinori , Nozaki Yuji , Rai Shinya , Kinoshita Koji , Funauchi Masanori , Matsumura Itaru
Published: May 2021

A 35-year-old male was referred to our hospital with dysesthesia of the lower extremities that had begun six months earlier. A blood test revealed the presence of various antibodies, suggesting a collagen-related peripheral neuropathy. However, a history of repeated shingles and sex with males was noted, and the patient was tested for and diagnosed with human immunodeficiency virus (HIV) infection. Based on the manifestations and laboratory data, including the results of immunological and urinary tests, he was further diagnosed with concomitant systemic lupus erythematosus (SLE). The activity of SLE improved with antiretroviral therapy. There is currently no established treatment for AIDS complicated with SLE. Indeed, because HIV treatment involves the activation of immune function and SLE treatment involves immunosuppression, any treatments for the two conditions would be in conflict. It is thus necessary to select a treatment strategy based on the condition of the individual patient. In addition, because HIV infection is relatively rare in Japan compared to other countries, rheumatologists in Japan must keep HIV infection in mind as a differential diagnosis for autoimmune diseases.
Metallic Material Selection and Prospective Surface Treatments for Proton Exchange Membrane Fuel Cell Bipolar Plates—A Review
Authors: Bohackova Tereza , Ludvik Jakub , Kouril Milan
Published: May 2021

The aim of this review is to summarize the possibilities of replacing graphite bipolar plates in fuel-cells. The review is mostly focused on metallic bipolar plates, which benefit from many properties required for fuel cells, viz. good mechanical properties, thermal and electrical conductivity, availability, and others. The main disadvantage of metals is that their corrosion resistance in the fuel-cell environment originates from the formation of a passive layer, which significantly increases interfacial contact resistance. Suitable coating systems prepared by a proper deposition method are eventually able to compensate for this disadvantage and make the replacement of graphite bipolar plates possible. This review compares coatings, materials, and deposition methods based on electrochemical measurements and contact resistance properties with respect to achieving appropriate parameters established by the DOE as objectives for 2020. An extraordinary number of studies have been performed, but only a minority of them provided promising results. One of these is the nanocrystalline β-Nb2N coating on AISI 430, prepared by the disproportionation reaction of Nb(IV) in molten salt, which satisfied the DOE 2020 objectives in terms of corrosion resistance and interfacial contact resistance. From other studies, TiN, CrN, NbC, TiC, or amorphous carbon-based coatings seem to be promising. This paper is novel in extracting important aspects for future studies and methods for testing the properties of metallic materials and factors affecting monitoring characteristics and parameters.
Microstructure and Mechanical Properties of NiTi-Based Eutectic Shape Memory Alloy Produced via Selective Laser Melting In-Situ Alloying by Nb
Authors: Polozov Igor , Popovich Anatoly
Published: May 2021

This paper presents the results of selective laser melting (SLM) process of a nitinol-based NiTiNb shape memory alloy. The eutectic alloy Ni45Ti45Nb10 with a shape memory effect was obtained by SLM in-situ alloying using a powder mixture of NiTi and Nb powder particles. Samples with a high relative density (>99%) were obtained using optimized process parameters. Microstructure, phase composition, tensile properties, as well as martensitic phase transformations temperatures of the produced alloy were investigated in as-fabricated and heat-treated conditions. The NiTiNb alloy fabricated using the SLM in-situ alloying featured the microstructure consisting of the NiTi matrix, fine NiTi+β-Nb eutectics, as well as residual unmelted Nb particles. The mechanical tests showed that the obtained alloy has a yield strength up to 436 MPa and the tensile strength up to 706 MPa. At the same time, in-situ alloying with Nb allowed increasing the hysteresis of martensitic transformation as compared to the alloy without Nb addition from 22 to 50 °C with an increase in Af temperature from −5 to 22 °C.
Facile Preparation of Granular Copper Films as Cathode for Enhanced Electrochemical Degradation of Methyl Orange
Authors: Xing Jiajie , Song Min , Yang Mengyao , Tan Xu , Li Fenglin , Wang Xixin , Zhao Jianling
Published: May 2021

In this paper, granular copper films (GCFs) were prepared through electrodeposition in CuSO4 solution containing triethanolamine, and the films were used as electro-Fenton-like cathodes for degradation of methyl orange (MO). The effects of triethanolamine concentration, pH value, current intensity and temperature on the morphology of the films, as well as the MO decolorization ratio (DR), were investigated in detail. Results show that when the concentration of triethanolamine is 0.2 wt%, the prepared GCF exhibits the best performance. Under room temperature and neutral conditions, no external O2 or catalyst, MO is completely decolorized after 240 min. Compared with the commonly used carbon cathode, the GCF cathode can increase the MO decolorization rate by approximately 70.9%. The kinetics of the electrochemical degradation reaction is also discussed.
Novel Cast Polyurethanes Obtained by Using Reactive Phosphorus-Containing Polyol: Synthesis, Thermal Analysis and Combustion Behaviors
Authors: Zagożdżon Izabela , Parcheta Paulina , Datta Janusz
Published: May 2021

Phosphorus-containing polyol applications in polyurethane synthesis can prevent volatilization of flame retardants and their migration on the surface of a material. In this work, novel cast polyurethanes were prepared by a one-step method with the use of different amounts of phosphorus-containing polyol, 4,4′–diphenylmethane diisocyanate and 1,4-butanediol. The chemical structure, thermal, physicochemical and mechanical properties and flame resistance of the prepared materials were investigated. The results obtained for cast flame-retarded polyurethanes were compared with cast polyurethane synthesized with commonly known polyether polyol. It has been shown that with an increasing amount of phosphorus content to polyurethane’s chemical structure, an increased flame resistance and char yield were found during combustion tests. Phosphorus polyol worked in both the condensed (reduced heat and mass exchange) and gas phase (inhibition of flame propagation during burning). The obtained materials contained phosphorus polyol, indicating higher thermal stability in an oxidative environment than an inert atmosphere.
Incorporation of Powder Particles into an Impeller-Stirred Liquid Bath through Vortex Formation
Authors: Komarov Sergey V. , Yamamoto Takuya , Arai Hirotada
Published: May 2021

The present study addresses the incorporation of fine particles into liquids via the creation of a large-scale swirling vortex on the liquid free surface using a rotary impeller positioned along the axis of a cylindrical vessel. Four types of particles are used in the experiments to investigate the incorporation efficiency of the particles into a water bath under different impeller rotation speeds. Additionally, the vortex characteristics are investigated numerically. The results reveal that two factors, namely the particle wettability and turbulent oscillations at the bottom part of vortex surface, play dominant roles in determining the particle incorporation behavior. Hydrophobic particles are incapable of being incorporated into the water bath under any of the conditions examined in the present study. Partly wettable particles are entrained into the water bath, with the efficiency increasing with the impeller rotation speed and particle size. This is because an increase in the impeller rotation speed causes vortex deformation, whereby its bottom part approaches the impeller blades where the turbulent surface oscillations reach maximum amplitudes. Another possible mechanism of particle incorporation is the effect of capillary increases of liquid into the spaces between particles, which accumulate on the bottom surface of the vortex.
Research on Surface Treatment and Interfacial Bonding Technology of Copper–Polymer Direct Molding Process
Authors: Cao Qingsong , Guo Rongsheng , Yang Feng , Rong Jian , Hu Guanghong
Published: May 2021

To realize the connection of copper and Polyphenylene sulfide (PPS) by metal–polymer direct molding, this paper combined anodic oxidation and chemical corrosion to treat the surface of copper, and carried out the injection molding experiment. An orthogonal experimental arrangement was used to identify the optimal electrolyte and etching solution for preparing a microstructure on a copper surface. The bonding and fracture mechanisms of the copper–polymer assembly were investigated through injection molding experiment and SEM technology. The results revealed that the phosphoric acid concentration had the most significant effect on the microstructure quality and etching solution containing 20% phosphoric acid produced a uniform microstructure with 25.77% porosity and 5.52 MPa bonding strength. Meanwhile, SEM images of the interface from bonding to fracture in the copper–polymer assembly indicated a well-filled polymer in the microstructure with a mainly cohesive fracture mode.
New Acceptor–Donor–Acceptor Systems Based on Bis-(Imino-1,8-Naphthalimide)
Authors: Kotowicz Sonia , Korzec Mateusz , Pająk Agnieszka Katarzyna , Golba Sylwia , Małecki Jan Grzegorz , Siwy Mariola , Grzelak Justyna , Maćkowski Sebastian , Schab-Balcerzak Ewa
Published: May 2021

In this paper, six novel symmetrical bis-(imino-1,8-naphthalimides) differing in core and N-substituent structure were synthesized, and their thermal (TGA, DSC), optical (UV-Vis, PL), electrochemical (DPV, CV) properties were evaluated. The compounds were stable to 280 °C and could be transferred into amorphous materials. Electrochemical investigations showed their ability to occur reductions and oxidations processes. They exhibited deep LUMO levels of about −3.22 eV and HOMO levels above −5.80 eV. The optical investigations were carried out in the solutions (polar and non-polar) and in films and blends with PVK:PBD. Bis-(imino-1,8-naphthalimides) absorbed electromagnetic radiation in the range of 243–415 nm and emitted light from blue to yellow. Their capacity for light emission under voltage was preliminarily tested in devices with an active layer consisting of a neat compound and a blend with PVK:PBD. The diodes emitted green or red light.
Model-Free Approach for the Configurational Analysis of Marine Natural Products
Authors: Köck Matthias , Reggelin Michael , Immel Stefan
Published: May 2021

The NMR-based configurational analysis of complex marine natural products is still not a routine task. Different NMR parameters are used for the assignment of the relative configuration: NOE/ROE, homo- and heteronuclear J couplings as well as anisotropic parameters. The combined distance geometry (DG) and distance bounds driven dynamics (DDD) method allows a model-free approach for the determination of the relative configuration that is invariant to the choice of an initial starting structure and does not rely on comparisons with (DFT) calculated structures. Here, we will discuss the configurational analysis of five complex marine natural products or synthetic derivatives thereof: the cis-palau’amine derivatives 1a and 1b, tetrabromostyloguanidine (1c), plakilactone H (2), and manzamine A (3). The certainty of configurational assignments is evaluated in view of the accuracy of the NOE/ROE data available. These case studies will show the prospective breadth of application of the DG/DDD method.
Fucoidans as Scientifically and Commercially Important Algal Polysaccharides
Authors: Sanjeewa K. K. Asanka , Jeon You-Jin
Published: May 2021

As a highly bioactive seaweed substance with many promising physiological activities, fucoidan has attracted attention from many industries all over the world [...]
Bioactive Natural Products from the Red Sea
Authors: Rateb Mostafa E. , Abdelmohsen Usama Ramadan
Published: May 2021

The marine environment has proven to be a rich source of diverse natural products with relevant activities such as anticancer, anti-inflammatory, antiepileptic, immunomodulatory, antifungal, antiviral, and antiparasitic [...]
Low Temperature and Cold Stress Significantly Increase Saxitoxins (STXs) and Expression of STX Biosynthesis Genes sxtA4 and sxtG in the Dinoflagellate Alexandrium catenella
Authors: Kim Hansol , Park Hyunjun , Wang Hui , Yoo Hah Young , Park Jaeyeon , Ki Jang-Seu
Published: May 2021

Toxic dinoflagellate Alexandrium spp. produce saxitoxins (STXs), whose biosynthesis pathway is affected by temperature. However, the link between the regulation of the relevant genes and STXs’ accumulation and temperature is insufficiently understood. In the present study, we evaluated the effects of temperature on cellular STXs and the expression of two core STX biosynthesis genes (sxtA4 and sxtG) in the toxic dinoflagellate Alexandrium catenella Alex03 isolated from Korean waters. We analyzed the growth rate, toxin profiles, and gene responses in cells exposed to different temperatures, including long-term adaptation (12, 16, and 20 °C) and cold and heat stresses. Temperature significantly affected the growth of A. catenella, with optimal growth (0.49 division/day) at 16 °C and the largest cell size (30.5 µm) at 12 °C. High concentration of STXs eq were detected in cells cultured at 16 °C (86.3 fmol/cell) and exposed to cold stress at 20→12 °C (96.6 fmol/cell) compared to those at 20 °C and exposed to heat stress. Quantitative real-time PCR (qRT-PCR) revealed significant gene expression changes of sxtA4 in cells cultured at 16 °C (1.8-fold) and cold shock at 20→16 °C (9.9-fold). In addition, sxtG was significantly induced in cells exposed to cold shocks (20→16 °C; 19.5-fold) and heat stress (12→20 °C; 25.6-fold). Principal component analysis (PCA) revealed that low temperature (12 and 16 °C) and cold stress were positively related with STXs’ production and gene expression levels. These results suggest that temperature may affect the toxicity and regulation of STX biosynthesis genes in dinoflagellates.
Laboratory Efficacy of Locally Available Backwashing Methods at Removing Fouling in Hollow-Fiber Membrane Filters Used for Household Water Treatment
Authors: Heylen Camille , Oliveira Aguiar Alice , String Gabrielle , Domini Marta , Goff Nathaniel , Murray Anna , Asatekin Ayse , Lantagne Daniele
Published: May 2021

Hollow-fiber membrane filters (HFMFs) for household water treatment (HWT) can efficaciously remove disease-causing organisms in laboratory settings. However, lower effectiveness in use in low- and middle-income countries (LMICs) and humanitarian contexts (HCs) has been observed and attributed to membrane fouling and the associated cleaning. In LMICs/HCs, it is not possible to prevent and control fouling using commonly known methods (e.g., testing influent water, maintenance regimes), and the literature on fouling/cleaning of HFMFs distributed in LMICs is scarce. As such, controlled laboratory experiments were conducted to determine the efficacy of locally available (in LMICs/HCs) backwashing solutions at removing fouling using different influent waters and HFMF types. Four commonly distributed HFMFs were selected; fouling layers were developed by filtering three influent water compositions, representing LMIC/HC waters, for 10-days, and bleach, water, or vinegar backwashing solutions were used for daily backwashing. Filter performance indicators included: fiber mechanical properties (strain at break, break force), water quantity performance (flow), water quality performance (turbidity, E. coli), and imaging. The study found fouling developed rapidly and altered mechanical properties and water quantity indicators within 200 h of filtration. Fouling did not decrease water quality indicators. Backwashing improved the filter’s mechanical properties and water quantity performance, but it did not fully recover the initial performance. Additionally, recovery differed between backwashing solutions, and no universal cleaning recommendation appropriate for HFMFs in LMICs/HCs was identified. Overall, fouling development and control depended on HFMF type, influent water quality, and backwashing solution type; thus, caution before distributing HFMFs for long-term use in LMICs/HCs is recommended.
A Fiber Ring Laser Sensor with a Side Polished Evanescent Enhanced Fiber for Highly Sensitive Temperature Measurement
Authors: Lin Weihao , Liu Yibin , Shao Liyang , Vai Mang I.
Published: May 2021

We demonstrate a highly sensitive and practical fiber-based temperature sensor system. The sensor is constructed based on a fiber ring laser (FRL) as well as a side-polished fiber filled with isopropanol. The laser cavity of the sensing part fiber is polished by the wheel fiber polishing system with residual thickness (RT) is selected to detect the temperature in the FRL. Thanks to the high thermo-optic coefficient of isopropanol, the sensitivity of the proposed temperature sensor could be effectively improved by filling isopropanol in the cost-less side polished single mode fiber. Refractive index (RI) of isopropanol changes with the surrounding temperature variation allowing high-sensitivity temperature sensing. Experimental results demonstrate that the side polished fiber can efficiently excite high-order cladding modes which enhance the modular interference increase the interaction between the evanescent wave and the isopropanol. Besides, the results show that the sensitivity can be as high as 2 nm/°C in the temperature range of 25–35 °C.
Polyethylene Glycol Functionalized Graphene Oxide Nanoparticles Loaded with Nigella sativa Extract: A Smart Antibacterial Therapeutic Drug Delivery System
Authors: Jihad Mustafa A. , Noori Farah T. M. , Jabir Majid S. , Albukhaty Salim , AlMalki Faizah A. , Alyamani Amal A.
Published: May 2021

Flaky graphene oxide (GO) nanoparticles (NPs) were synthesized using Hummer’s method and then capped with polyethylene glycol (PEG) by an esterification reaction, then loaded with Nigella sativa (N. sativa) seed extract. Aiming to investigate their potential use as a smart drug delivery system against Staphylococcus aureus and Escherichia coli, the spectral and structural characteristics of GO-PEG NPs were comprehensively analyzed by XRD, AFM, TEM, FTIR, and UV- Vis. XRD patterns revealed that GO-PEG had different crystalline structures and defects, as well as a higher interlayer spacing. AFM results showed GONPs with the main grain size of 24.41 nm, while GONPs–PEG revealed graphene oxide aggregation with the main grain size of 287.04 nm after loading N. sativa seed extract, which was verified by TEM examination. A strong OH bond appeared in FTIR spectra. Furthermore, UV- Vis absorbance peaks at (275, 284, 324, and 327) nm seemed to be correlated with GONPs, GO–PEG, N. sativa seed extract, and GO –PEG- N. sativa extract. The drug delivery system was observed to destroy the bacteria by permeating the bacterial nucleic acid and cytoplasmic membrane, resulting in the loss of cell wall integrity, nucleic acid damage, and increased cell-wall permeability.
Assessment of the Biocompatibility of Cucurbiturils in Blood Cells
Authors: Aktanova Alina , Abramova Tatjana , Pashkina Ekaterina , Boeva Olga , Grishina Lyubov , Kovalenko Ekaterina , Kozlov Vladimir
Published: May 2021

Currently, cucurbiturils are being actively researched all over the world. Research is focused on the ways of improving the solubility and selectivity of cucurbiturils, increasing the stability of the complexes with other particles in various media and enhancing their ability to bind and release various substances. The most significant area of our research is the assessment of safety, studying the biological properties and synergistic effects of cucurbiturils during complexation with drugs. In this article, the hemocompatibility of erythrocytes and leukocytes with cucurbiturils was investigated. We demonstrated that cucurbiturils have no cytotoxic effect, even at high concentrations (1 mM) and do not affect the viability of PBMCs. However, cucurbiturils can increase the level of the early apoptosis of lymphocytes and cucurbit[7]uril enhances hemolysis in biologically relevant media. Despite this, cucurbiturils are fairly safe organic molecules in concentrations up to 0.3 mM. Thus, we believe that it will become possible to use polymer nanostructures as drug delivery systems in clinical practice, since cucurbiturils can be modified to improve pharmacological properties.
Nutrient Intake in Children 4–13 Years Old in Ibadan, Nigeria
Authors: Tassy Marie , Eldridge Alison L. , Sanusi Rasaki A. , Ariyo Oluwaseun , Ogundero AnuOluwapo , Eyinla Tolu E. , Wang Dantong
Published: May 2021

The paucity of adequate data on dietary and nutrient intakes of school-age children is a barrier to addressing malnutrition and associated risks in Nigeria. This study included 955 children aged 4–13 years from Ibadan, Nigeria, using a stratified random sampling design. Information on family socio-demographic characteristics was reported, and child anthropometrics were measured. Dietary intake data were collected using a multi-pass 24 h dietary recall method; 20% of subjects completed a second 24 h recall to estimate usual nutrient intakes. Means and distributions of usual intakes of energy and nutrients as well as prevalence of inadequacy were estimated. Usual energy intake (kcal/day) was 1345 and 1590 for younger (4–8 years) and older (9–13 years) age groups, respectively. The macronutrient intakes of most children did not conform to Adequate Macronutrient Distribution Ranges (AMDRs), which were characterized by a higher proportion of energy from carbohydrates and lower proportion from total fats. Protein intake was largely within the AMDR. Compared to recommendations, over 60% of 4–8-year-old children had inadequate intakes of calcium, copper, iron, folate, and vitamins A, D, and E. There were more micronutrient inadequacies in the older children. This study identifies nutrition gaps and suggests future research and education to improve child nutrition in Nigeria.
Quality of Surface Texture and Mechanical Properties of PLA and PA-Based Material Reinforced with Carbon Fibers Manufactured by FDM and CFF 3D Printing Technologies
Authors: Saharudin Mohd Shahneel , Hajnys Jiri , Kozior Tomasz , Gogolewski Damian , Zmarzły Paweł
Published: May 2021

The paper presents the results of mechanical tests of models manufactured with two 3D printing technologies, FDM and CFF. Both technologies use PLA or PA-based materials reinforced with carbon fibers. The work includes both uniaxial tensile tests of the tested materials and metrological measurements of surfaces produced with two 3D printing technologies. The test results showed a significant influence of the type of technology on the strength of the models built and on the quality of the technological surface layer. After the analysis of the parameters of the primary profile, roughness and waviness, it can be clearly stated that the quality of the technological surface layer is much better for the models made with the CFF technology compared to the FDM technology. Furthermore, the tensile strength of the models manufactured of carbon fiber-enriched material is much higher for samples made with CFF technology compared to FDM.
Sex Manuals in Malay Manuscripts as Another Transcript of Gender Relations
Authors: Mohamad Maznah
Published: May 2021

This article interprets the narratives of sex manuals produced within the Malay-Indonesian archipelago before the coming of Western colonialism and the dawn of postcolonial Islamic resurgence. In the collection of Malaysian libraries and museums, these manuscripts are largely classified as Kitab Jimak and Kitab Tib. They are all written in the Malay language with indigenous references, though the contents are likely derived from a common genre of texts transmitted from an early Arab-Islamic world and circulated within the region before the coming of European colonialism. The corpora of sexual knowledge in these texts emphasises the valorisation of sexual pleasure in conjugal relationships. Through an extensive list of prescriptions—from sexual techniques to diet, food taboos, medicine, pharmacopoeia, mantras, charms, and astrological knowledge—a near-sacral sexual experience is aspired. Couples are guided in their attainment of pleasure (nikmat) through the adherence of Islamic ethics (akhlak), rules (hukum), and etiquette (tertib). The fulfilment of women’s desire in the process is central in these observances. Nevertheless, despite placing much emphasis on mutual pleasure, these texts also contain ambiguous and paradoxical pronouncements on the position of women, wavering from veneration to misogyny. The article also highlights how intertextual studies of similar texts throughout the Islamic world can be a new focus of studies on the early history of gender and sexuality in Islam.
Quantitative Analysis of Real-Time Infrared Thermography for the Assessment of Lumbar Sympathetic Blocks: A Preliminary Study
Authors: Cañada-Soriano Mar , Priego-Quesada José Ignacio , Bovaira Maite , García-Vitoria Carles , Salvador Palmer Rosario , Cibrián Ortiz de Anda Rosa , Moratal David
Published: May 2021

Lumbar sympathetic blocks (LSBs) are commonly performed to treat pain ailments in the lower limbs. LSBs involve injecting local anesthetic around the nerves. The injection is guided by fluoroscopy which is sometimes considered to be insufficiently accurate. The main aim was to analyze the plantar foot skin temperature data acquired while performing LSBs in patients with complex regional pain syndrome (CRPS) affecting the lower limbs. Forty-four LSBs for treating lower limb CRPS in 13 patients were assessed. Pain medicine physicians visualized the infrared thermography (IRT) video in real time and classified the performance depending on the observed thermal changes within the first 4 min. Thirty-two percent of the cases did not register temperature variations after lidocaine was injected, requiring the needle to be relocated. Differences between moments are indicated using the 95% confidence intervals of the differences (CI 95%), the Cohen effect size (ES) and the significance (p value). In successful cases, after injecting lidocaine, increases at minute 7 for the mean (CI 95% (1.4, 2.1 °C), p < 0.001 and ES = 0.5), at minute 5 for maximum temperature (CI 95% (2.3, 3.3 °C), p < 0.001 and ES = 0.6) and at minute 6 for SD (CI 95% (0.2, 0.3 °C), p < 0.001 and ES = 0.5) were observed. The results of our preliminary study showed that the measurement of skin temperature in real time by infrared thermography is valuable for assessing the success of lumbar sympathetic blocks.
Concentration and Persistence of Healthcare Spending: Evidence from China
Authors: Chen Hua , Peng Xiaobo , Shen Menghan
Published: May 2021

One way to reduce healthcare costs is to target the high spenders who remain persistently high in cost over time. Using claims data from China between 2010 to 2014, we sought to identify the level of concentration in spending and the proportion of spenders whose costs remain high over five years. Using a transition matrix and a linear regression strategy, we find that the top 10% of the spenders account for more than 50% of total expenditures. Of the individuals who were in the top 10% in 2010, 33.6% remained in the top 10% one year later and 23.6% were still in that category even four years later. Past spending plays a major role in the dynamic of health spending. A 10% increase in expenditure is associated with an increase of 0.36% to 1.33% of spending in the future. Persistence has some heterogeneity in terms of age, gender, and income level. Many diseases have strong predictive power for future spending. Research on the concentration and persistence of health expenditures will inform policymakers in terms of controlling costs and providing protection for catastrophic spending.
Vocabulary Learning Based on Learner-Generated Pictorial Annotations: Using Big Data as Learning Resources
Authors: Zou Di , Xie Haoran
Published: May 2021

This research discusses the potential of using big data for vocabulary learning from the perspective of learner-generated pictorial annotations. Pictorial annotations lead to effective vocabulary learning, the creation of which is however challenging and time-consuming. As user-generated annotations promote active learning, and in the big data era, data sources in social media platforms are not only huge but also user-generated, the proposal of using social media data to establish a natural and semantic connection between pictorial annotations and words seems feasible. This research investigated learners’ perceptions of creating pictorial annotations using Google images and social media images, learners’ evaluation of the learner-generated pictorial annotations, and the effectiveness of Google pictorial annotations and social media pictorial annotations in promoting vocabulary learning. A total of 153 undergraduates participated in the research, some of whom created pictorial annotations using Google and social media data, some evaluated the annotations, and some learned the target words with the annotations. The results indicated positive attitudes towards using Google and social media data sets as resources for language enhancement, as well as significant effectiveness of learner-generated Google pictorial annotations and social media pictorial annotations in promoting both initial learning and retention of target words. Specifically, we found that (i) Google images were more appropriate and reliable for pictorial annotations creation, and therefore they achieved better outcomes when learning with the annotations created with Google images than images from social media, and (ii) the participants who created word lists that integrate pictorial annotations were likely to engage in active learning when they selected and organized the verbal and visual information of target words by themselves and actively integrated such information with their prior knowledge.
Design Framework Based on TEC21 Educational Model and Education 4.0 Implemented in a Capstone Project: A Case Study of an Electric Vehicle Suspension System
Authors: López Hugo A , Ponce Pedro , Molina Arturo , Ramírez-Montoya María Soledad , Lopez-Caudana Edgar
Published: May 2021

Nowadays, engineering students have to improve specific competencies to tackle the challenges of 21st-century-industry, referred to as Industry 4.0. Hence, this article describes the integration and implementation of Education 4.0 strategies with the new educational model of our university to respond to the needs of Industry 4.0 and society. The TEC21 Educational Model implemented at Tecnologico de Monterrey in Mexico aims to develop disciplinary and transversal competencies for creative and strategic problem-solving of present and future challenges. Education 4.0, as opposed to traditional education, seeks to provide solutions to these challenges through innovative pedagogies supported by emerging technologies. This article presents a case study of a Capstone project developed with undergraduate engineering students. The proposed structure integrates the TEC21 model and Education 4.0 through new strategies and laboratories, all linked to industry. The results of a multidisciplinary project focused on an electric vehicle racing team are presented, composed of Education 4.0 elements and competencies development in leadership, innovation, and entrepreneurship. The project was a collaboration between academia and the productive sector. The results verified the students’ success in acquiring the necessary competencies and skills to become technological leaders in today’s modern industry. One of the main contributions shown is a suitable education framework for bringing together the characteristics established by Education 4.0 and achieved by our educational experience based on Education 4.0.
Application of an Innovative Model for the Risk Management of COVID-19 in a Multinational Manufacturing Company
Authors: Lovreglio Piero , Stufano Angela , Cagnazzo Francesco , Bartolomeo Nicola , Iavicoli Ivo
Published: May 2021

The COVID-19 incidence in 61 manufacturing plants in Europe (EU), North America (NA) and Latin-America (LATAM) was compared with the incidence observed in the countries where the plants are located in order to evaluate the application of an innovative model for COVID-19 risk management. Firstly, a network of local and global teams was created, including an external university occupational physician team for scientific support. In July 2020, global prevention guidelines for the homogenous management of the pandemic were applied, replacing different site or regional procedures. A tool for COVID-19 monitoring was implemented to investigate the relationship between the incidence rates inside and outside the plants. In the period of May–November 2020, 565 confirmed cases (EU 330, NA 141, LATAM 94) were observed among 20,646 workers with different jobs and tasks, and in the last two months 85% EU and 70% NA cases were recorded. Only in 10% of cases was a possible internal origin of the contagion not excluded. In the EU and NA, unlike LATAM, the COVID-19 incidence rates inside the sites punctually followed the rising trend outside. In conclusion, the model, combining a global approach with the local application of the measures, maintains the sustainability in the manufacturing industry.
Improving Multivariate Microaggregation through Hamiltonian Paths and Optimal Univariate Microaggregation
Authors: Maya-López Armando , Casino Fran , Solanas Agusti
Published: May 2021

The collection of personal data is exponentially growing and, as a result, individual privacy is endangered accordingly. With the aim to lessen privacy risks whilst maintaining high degrees of data utility, a variety of techniques have been proposed, being microaggregation a very popular one. Microaggregation is a family of perturbation methods, in which its principle is to aggregate personal data records (i.e., microdata) in groups so as to preserve privacy through k-anonymity. The multivariate microaggregation problem is known to be NP-Hard; however, its univariate version could be optimally solved in polynomial time using the Hansen-Mukherjee (HM) algorithm. In this article, we propose a heuristic solution to the multivariate microaggregation problem inspired by the Traveling Salesman Problem (TSP) and the optimal univariate microaggregation solution. Given a multivariate dataset, first, we apply a TSP-tour construction heuristic to generate a Hamiltonian path through all dataset records. Next, we use the order provided by this Hamiltonian path (i.e., a given permutation of the records) as input to the Hansen-Mukherjee algorithm, virtually transforming it into a multivariate microaggregation solver we call Multivariate Hansen-Mukherjee (MHM). Our intuition is that good solutions to the TSP would yield Hamiltonian paths allowing the Hansen-Mukherjee algorithm to find good solutions to the multivariate microaggregation problem. We have tested our method with well-known benchmark datasets. Moreover, with the aim to show the usefulness of our approach to protecting location privacy, we have tested our solution with real-life trajectories datasets, too. We have compared the results of our algorithm with those of the best performing solutions, and we show that our proposal reduces the information loss resulting from the microaggregation. Overall, results suggest that transforming the multivariate microaggregation problem into its univariate counterpart by ordering microdata records with a proper Hamiltonian path and applying an optimal univariate solution leads to a reduction of the perturbation error whilst keeping the same privacy guarantees.
Mathematical Algorithm for Identification of Eukaryotic Promoter Sequences
Authors: Korotkov Eugene V. , Suvorova Yulia. M. , Nezhdanova Anna V. , Gaidukova Sofia E. , Yakovleva Irina V. , Kamionskaya Anastasia M. , Korotkova Maria A.
Published: May 2021

Identification of promoter sequences in the eukaryotic genome, by computer methods, is an important task of bioinformatics. However, this problem has not been solved since the best algorithms have a false positive probability of 10−3–10−4 per nucleotide. As a result of full genome analysis, there may be more false positives than annotated gene promoters. The probability of a false positive should be reduced to 10−6–10−8 to reduce the number of false positives and increase the reliability of the prediction. The method for multi alignment of the promoter sequences was developed. Then, mathematical methods were developed for calculation of the statistically important classes of the promoter sequences. Five promoter classes, from the rice genome, were created. We developed promoter classes to search for potential promoter sequences in the rice genome with a false positive number less than 10−8 per nucleotide. Five classes of promoter sequences contain 1740, 222, 199, 167 and 130 promoters, respectively. A total of 145,277 potential promoter sequences (PPSs) were identified. Of these, 18,563 are promoters of known genes, 87,233 PPSs intersect with transposable elements, and 37,390 PPSs were found in previously unannotated sequences. The number of false positives for a randomly mixed rice genome is less than 10−8 per nucleotide. The method developed for detecting PPSs was compared with some previously used approaches. The developed mathematical method can be used to search for genes, transposable elements, and transcript start sites in eukaryotic genomes.
Washability of E-Textiles: Failure Modes and Influences on Washing Reliability
Authors: Rotzler Sigrid , Schneider-Ramelow Martin
Published: May 2021

E-textiles, hybrid products that incorporate electronic functionality into textiles, often need to withstand washing procedures to ensure textile typical usability. Yet, the washability—which is essential for many e-textile applications like medical or sports due to hygiene requirements—is often still insufficient. The influence factors for washing damage in textile integrated electronics as well as common weak points are not extensively researched, which makes a targeted approach to improve washability in e-textiles difficult. As a step towards reliably washable e-textiles, this review bundles existing information and findings on the topic: a summary of common failure modes in e-textiles brought about by washing as well as influencing parameters that affect the washability of e-textiles. The findings of this paper can be utilized in the development of e-textile systems with an improved washability.
Techno-Economic Optimization of Medium Temperature Solar-Driven Subcritical Organic Rankine Cycle
Authors: Roumpedakis Tryfon C. , Fostieris Nikolaos , Braimakis Konstantinos , Monokrousou Evropi , Charalampidis Antonios , Karellas Sotirios
Published: May 2021

The present work focuses on the techno-economic assessment and multi-objective genetic algorithm optimization of small-scale (40 kWth input), solar Organic Rankine Cycle (ORC) systems driven by medium-to-high temperature (up to 210 °C) parabolic dish (PDC) and trough (PTC) collectors. The ORCs are designed to maximize their nominal thermal efficiency for several natural hydrocarbon working fluids. The optimization variables are the solar field area and storage tank capacity, with the goal of minimizing the levelized cost of produced electricity (LCoE) and maximizing the annual solar conversion efficiency. The lowest LCOE (0.34 €/kWh) was obtained in Athens for a high solar field area and low storage tank capacity. Meanwhile, the maximum annual solar conversion efficiencies (10.5–11%) were obtained in northern cities (e.g., Brussels) at lower solar field locations. While PTCs and PDCs result in similar efficiencies, the use of PTCs is more cost-effective. Among the working fluids, Cyclopentane and Cyclohexane exhibited the best performance, owing to their high critical temperatures. Notably, the systems could be more profitable at higher system sizes, as indicated by the 6% LCoE decrease of the solar ORC in Athens when the nominal heat input was increased to 80 kWth.