bluuebunny/crossref_metadata_2025 huggingface dataset:
Sea Turtles in the Cancer Risk Landscape: A Global Meta-Analysis of Fibropapillomatosis Prevalence and Associated Risk Factors
Authors: Dujon Antoine M. , Schofield Gail , Venegas Roberto M. , Thomas Frédéric , Ujvari Beata
Published: October 2021

Several cancer risk factors (exposure to ultraviolet-B, pollution, toxins and pathogens) have been identified for wildlife, to form a “cancer risk landscape.” However, information remains limited on how the spatiotemporal variability of these factors impacts the prevalence of cancer in wildlife. Here, we evaluated the cancer risk landscape at 49 foraging sites of the globally distributed green turtle (Chelonia mydas), a species affected by fibropapillomatosis, by integrating data from a global meta-analysis of 31 publications (1994–2019). Evaluated risk factors included ultraviolet light exposure, eutrophication, toxic phytoplanktonic blooms, sea surface temperature, and the presence of mechanical vectors (parasites and symbiotic species). Prevalence was highest in areas where nutrient concentrations facilitated the emergence of toxic phytoplankton blooms. In contrast, ultraviolet light exposure and the presence of parasitic and/or symbiotic species did not appear to impact disease prevalence. Our results indicate that, to counter outbreaks of fibropapillomatosis, management actions that reduce eutrophication in foraging areas should be implemented.
Palm Foliage as Pathways of Pathogenic Botryosphaeriaceae Fungi and Host of New Lasiodiplodia Species from Mexico
Authors: Douanla-Meli Clovis , Scharnhorst Andreas
Published: October 2021

Tropical palm foliage is increasingly imported to satisfy the steady growing demand in European floristry. This palm foliage presumably carries along diverse fungi whose taxonomic and functional diversity have not been addressed so far. The present study investigated Botryosphaeriaceae fungi associated with the foliage of palm species Chamaedorea elegans, C. metallica, C. seifrizii, Dypsis lutescens and Lodoicea maldivica imported from Mexico. Five species were identified using combined morphological characterisation and multilocus phylogenetic analyses based on ITS, TEF-1α, TUB2 and RPB2. In addition to Endomelanconiopsis endophytica, Lasiodiplodia brasiliensis and L. euphorbicola, two new species, namely, L. lodoiceae sp. nov. and L. mexicanensis sp. nov, are proposed. Apart from E. endophytica, mostly known as endophyte, L. brasiliensis and L. euphorbicola are responsible for different rot diseases and the dieback of important tropical crop plants. In pathogenicity tests on the temperate pome fruits apple (Malus domestica) and pear (Pyrus communis), all six Botryosphaeriaceae species induced necrotic lesions at different degrees of severity, with highest the aggressiveness from L. euphorbicola and L. mexicanensis on apple and from L. mexicanensis on pear. The results indicate that tropical palm foliage can be a pathway of potentially pathogenic fungi that may give rise to concerns with regard to plant health in the destination countries.
Anaplasma phagocytophilum and Anaplasma ovis–Emerging Pathogens in the German Sheep Population
Authors: Bauer Benjamin Ulrich , Răileanu Cristian , Tauchmann Oliver , Fischer Susanne , Ambros Christina , Silaghi Cornelia , Ganter Martin
Published: October 2021

Knowledge on the occurrence of pathogenic tick-borne bacteria Anaplasma phagocytophilum and Anaplasma ovis is scarce in sheep from Germany. In 2020, owners from five flocks reported ill thrift lambs and ewes with tick infestation. Out of 67 affected sheep, 55 animals were clinically examined and hematological values, blood chemistry and fecal examinations were performed to investigate the underlying disease causes. Serological tests (cELISA, IFAT) and qPCR were applied to all affected sheep to rule out A. phagocytophilum and A. ovis as a differential diagnosis. Ticks were collected from selected pastures and tested by qPCR. Most animals (n = 43) suffered from selenium deficiency and endoparasites were detected in each flock. Anaplasma spp. antibodies were determined in 59% of examined sheep. Seventeen animals tested positive for A. phagocytophilum by qPCR from all flocks and A. phagocytophilum was also detected in eight pools of Ixodes ricinus. Anaplasma phagocytophilum isolates from sheep and ticks were genotyped using three genes (16S rRNA, msp4 and groEL). Anaplasma ovis DNA was identified in six animals from one flock. Clinical, hematological and biochemical changes were not significantly associated with Anaplasma spp. infection. The 16S rRNA analysis revealed known variants of A. phagocytophilum, whereas the msp4 and groEL showed new genotypes. Further investigations are necessary to evaluate the dissemination and health impact of both pathogens in the German sheep population particularly in case of comorbidities.
A Systematic Review of Drug-Loaded Electrospun Nanofiber-Based Ophthalmic Inserts
Authors: Omer Safaa , Zelkó Romána
Published: October 2021

Currently, ocular inserts and nanoparticles have received much attention due to the limited bioavailability of conventional eye preparations and the toxicity problems of systemic drug administration. The current systematic review aims to present recent studies on the use of electrospun nanofiber-based ocular inserts to improve the bioavailability of drugs used for different ophthalmic diseases. A systematic search was performed in PubMed, Ovid Medline, Web of Science, ScienceDirect, Scopus, Reaxys, Google Scholar, and Google Patents/Espacenet taking “drug-loaded”, “nanofibers”, and “ophthalmic inserts” and their equivalent terms as keywords. The search was limited to original and peer-reviewed studies published in 2011–2021 in English language. Only 13 out of 795 articles and 15 out of 197 patents were included. All results revealed the success of nanofiber-based ocular inserts in targeting and improved bioavailability. Ocular inserts based on nanofibers can be used as safe, efficient carriers for the treatment of anterior and posterior eye diseases.
RNAi-Based Approaches for Pancreatic Cancer Therapy
Authors: Kim Min Ju , Chang Hyeyoun , Nam Gihoon , Ko Youngji , Kim Sun Hwa , Roberts Thomas M. , Ryu Ju Hee
Published: October 2021

Pancreatic cancer is one of the most lethal forms of cancer, predicted to be the second leading cause of cancer-associated death by 2025. Despite intensive research for effective treatment strategies and novel anticancer drugs over the past decade, the overall patient survival rate remains low. RNA interference (RNAi) is capable of interfering with expression of specific genes and has emerged as a promising approach for pancreatic cancer because genetic aberrations and dysregulated signaling are the drivers for tumor formation and the stromal barrier to conventional therapy. Despite its therapeutic potential, RNA-based drugs have remaining hurdles such as poor tumor delivery and susceptibility to serum degradation, which could be overcome with the incorporation of nanocarriers for clinical applications. Here we summarize the use of small interfering RNA (siRNA) and microRNA (miRNA) in pancreatic cancer therapy in preclinical reports with approaches for targeting either the tumor or tumor microenvironment (TME) using various types of nanocarriers. In these studies, inhibition of oncogene expression and induction of a tumor suppressive response in cancer cells and surrounding immune cells in TME exhibited a strong anticancer effect in pancreatic cancer models. The review discusses the remaining challenges and prospective strategies suggesting the potential of RNAi-based therapeutics for pancreatic cancer.
Hydroxyapatite Nanoparticles in Drug Delivery: Physicochemistry and Applications
Authors: Lara-Ochoa Sofía , Ortega-Lara Wendy , Guerrero-Beltrán Carlos Enrique
Published: October 2021

Hydroxyapatite (HAP) has been the gold standard in the biomedical field due to its composition and similarity to human bone. Properties such as shape, size, morphology, and ionic substitution can be tailored through the use of different synthesis techniques and compounds. Regardless of the ability to determine its physicochemical properties, a conclusion for the correlation with the biological response it is yet to be found. Hence, a special focus on the most desirable properties for an appropriate biological response needs to be addressed. This review provides an overview of the fundamental properties of hydroxyapatite nanoparticles and the characterization of physicochemical properties involved in their biological response and role as a drug delivery system. A summary of the main chemical properties and applications of hydroxyapatite, the advantages of using nanoparticles, and the influence of shape, size, functional group, morphology, and crystalline phase in the biological response is presented. A special emphasis was placed on the analysis of chemical and physical interactions of the nanoparticles and the cargo, which was explained through the use of spectroscopic and physical techniques such as FTIR, Raman, XRD, SEM, DLS, and BET. We discuss the properties tailored for hydroxyapatite nanoparticles for a specific biomolecule based on the compilation of studies performed on proteins, peptides, drugs, and genetic material.
Exosomes as a New Delivery Vehicle in Inflammatory Bowel Disease
Authors: Wang Xiaomei , Zhou Guoliang , Zhou Wanwan , Wang Xin , Wang Xiao , Miao Chenggui
Published: October 2021

Inflammatory bowel disease (IBD) is a type of chronic relapsing inflammatory disease. The pathogenesis of IBD is still unclear, which may involve environmental factors, genetic factors, intestinal microbiota disorder, and abnormal immune responses. Exosomes (30–150 nm) are found in various body fluids, including blood, saliva, urine, and cerebrospinal fluid. Exosomes mediate intercellular communication and regulate cell biological activity by carrying non-coding RNAs, proteins, and lipids. There is evidence that exosomes are involved in the pathogenesis of IBD. In view of the important roles of exosomes in the pathogenesis of IBD, this work systematically reviews the latest research progress of exosomes in IBD, especially the roles of exosomes as non-coding RNA delivery systems in the pathogenesis of IBD, including a disordered immune response, barrier function, and intestinal microbiota. The review will help to clarify the pathogenesis of IBD and explore new diagnostic markers and therapeutic targets for patients with IBD.
Aptamers in Virology—A Consolidated Review of the Most Recent Advancements in Diagnosis and Therapy
Authors: Yadavalli Tejabhiram , Volety Ipsita , Shukla Deepak
Published: October 2021

The use of short oligonucleotide or peptide molecules as target-specific aptamers has recently garnered substantial attention in the field of the detection and treatment of viral infections. Based on their high affinity and high specificity to desired targets, their use is on the rise to replace antibodies for the detection of viruses and viral antigens. Furthermore, aptamers inhibit intracellular viral transcription and translation, in addition to restricting viral entry into host cells. This has opened up a plethora of new targets for the research and development of novel vaccines against viruses. Here, we discuss the advances made in aptamer technology for viral diagnosis and therapy in the past decade.
Methacryloyl-GlcNAc Derivatives Copolymerized with Dimethacrylamide as a Novel Antibacterial and Biocompatible Coating
Authors: Borgolte Max , Riester Oliver , Kacerova Tereza , Rentschler Simone , Schmidt Magnus S. , Jacksch Susanne , Egert Markus , Laufer Stefan , Csuk René , Deigner Hans-Peter
Published: October 2021

Improving medical implants with functional polymer coatings is an effective way to further improve the level of medical care. Antibacterial and biofilm-preventing properties are particularly desirable in the area of wound healing, since there is a generally high risk of infection, often with a chronic course in the case of biofilm formation. To prevent this we here report a polymeric design of polymer-bound N-acetyl-glucosamine-oligoethylene glycol residues that mimic a cationic, antibacterial, and biocompatible chitosan surface. The combination of easy to use, crosslinkable, thin, potentially 3D-printable polymethacrylate layering with antibacterial and biocompatible functional components will be particularly advantageous in the medical field to support a wide range of implants as well as wound dressings. Different polymers containing a N-acetylglucosamine-methacryloyl residue with oligoethylene glycol linkers and a methacryloyl benzophenone crosslinker were synthesized by free radical polymerization. The functional monomers and corresponding polymers were characterized by 1H, 13C NMR, and infrared (IR) spectroscopy. The polymers showed no cytotoxic or antiadhesive effects on fibroblasts as demonstrated by extract and direct contact cell culture methods. Biofilm formation was reduced by up to 70% and antibacterial growth by 1.2 log, particularly for the 5% GlcNAc-4EG polymer, as observed for Escherichia coli and Staphylococcus aureus as clinically relevant Gram-negative and Gram-positive model pathogens.
Evaluation of the Targeting and Therapeutic Efficiency of Anti-EGFR Functionalised Nanoparticles in Head and Neck Cancer Cells for Use in NIR-II Optical Window
Authors: Egnuni Teklu , Ingram Nicola , Mirza Ibrahim , Coletta P. Louise , McLaughlan James R.
Published: October 2021

Gold nanoparticles have been indicated for use in a diagnostic and/or therapeutic role in several cancer types. The use of gold nanorods (AuNRs) with a surface plasmon resonance (SPR) in the second near-infrared II (NIR-II) optical window promises deeper anatomical penetration through increased maximum permissible exposure and lower optical attenuation. In this study, the targeting and therapeutic efficiency of anti-epidermal growth factor receptor (EGFR)-antibody-functionalised AuNRs with an SPR at 1064 nm was evaluated in vitro. Four cell lines, KYSE-30, CAL-27, Hep-G2 and MCF-7, which either over- or under-expressed EGFR, were used once confirmed by flow cytometry and immunofluorescence. Optical microscopy demonstrated a significant difference (p < 0.0001) between targeted AuNRs (tAuNRs) and untargeted AuNRs (uAuNRs) in all four cancer cell lines. This study demonstrated that anti-EGFR functionalisation significantly increased the association of tAuNRs with each EGFR-positive cancer cell. Considering this, the MTT assay showed that photothermal therapy (PTT) significantly increased cancer cell death (>97%) in head and neck cancer cell line CAL-27 using tAuNRs but not uAuNRs, apoptosis being the major mechanism of cell death. This successful targeting and therapeutic outcome highlight the future use of tAuNRs for molecular photoacoustic imaging or tumour treatment through plasmonic photothermal therapy.
Association between ADCY9 Gene Polymorphisms and Ritodrine Treatment Outcomes in Patients with Preterm Labor
Authors: Lee Nari , Yoon Ha-Young , Park Jin-Young , Kim Young-Ju , Hwang Han-Sung , Yee Jeong , Gwak Hye-Sun
Published: October 2021

The purpose of this study was to investigate the genetic effects of ADCY9 on ritodrine responses in patients with preterm labor. Five single nucleotide polymorphisms (SNPs) of the ADYC9 gene in 163 patients in preterm labor were genotyped: rs879619, rs2601796, rs2531988, rs2531995, and rs2230739. Additionally, rs598961 of the PDE4B gene and rs1042719 of the ADRB2 gene were included for analysis. Patients with CC genotype of ADCY9 rs879619 had a 2.0-fold (95% confidence interval [CI]: 1.3, 3.2) higher hazard of time to delivery than T allele carriers. Patients with combined genotypes of CC in ADCY9 rs879619, AA in PDE4B rs598961, and GC, CC in ADRB2 rs1042719 showed a greater hazard of time to delivery than patients with other combinations (adjusted hazard ratio [AHR] 3.2; 95% CI: 1.7, 6.3), whereas patients carrying the C allele of ADCY9 rs2531995, G allele of PDE4B rs598961, and GG genotype of ADRB2 rs1042719 had a lower hazard of time to delivery than patients carrying other genotypes (AHR 0.4; 95% CI: 0.2, 0.7). Regarding ritodrine-induced adverse drug events (ADEs), height less than 160 cm and CC genotype of ADCY9 rs2531995 showed a greater risk of ADEs. The results of our study suggest that ADCY9 polymorphisms could affect the efficacy and safety of β2-adrenergic agonists.
Application of High Voltage Electrical Discharge Treatment to Improve Wheat Germination and Early Growth under Drought and Salinity Conditions
Authors: Marček Tihana , Kovač Tihomir , Jukić Katarina , Lončarić Ante , Ižaković Maja
Published: October 2021

The environmentally friendly, physical method of high voltage electrical discharge (HVED) was developed to improve the drought and salinity tolerance of two wheat genotypes. Unlike other plasma technologies, HVED treatment involves the discharge of electricity in water. In this study, the effect of HVED pretreatment on wheat germination and early vegetative growth under drought (0%, 15%, 20% and 30% PEG) and salinity (0, 90, 160 and 230 mM NaCl) stress conditions was investigated. HVED-exposed seeds showed altered seed surfaces and became more permeable to water uptake, resulting in higher germination percentages, germination index values, and shoot and root growth under the control and all drought and salinity concentrations. Moreover, the electrical conductivity of the water medium increased significantly, indicating HVED-induced reactions of ionization and dissociations of water molecules occurred. In addition, HVED pretreatment in the salt experiment improved the tolerance index values of the shoots and roots. The most pronounced genotypic variations occurred under the highest stress levels (30% PEG or 230 mM NaCl) and varied with the stress intensity and growth stage. The study results indicate that HVED pretreatment has the potential to improve drought and salt tolerance in wheat.
High Phenotypic Plasticity in a Prominent Plant Invader along Altitudinal and Temperature Gradients
Authors: Gentili Rodolfo , Ambrosini Roberto , Augustinus Benno A. , Caronni Sarah , Cardarelli Elisa , Montagnani Chiara , Müller-Schärer Heinz , Schaffner Urs , Citterio Sandra
Published: October 2021

Studies on plant growth and trait variation along environmental gradients can provide important information for identifying drivers of plant invasions and for deriving management strategies. We used seeds of the annual plant invader Ambrosia artemisiifolia L. (common ragweed) collected from an agricultural site in Northern Italy (226 m. a.s.l; Mean Annual Air Temperature: 12.9 °C; precipitations: 930 mm) to determine variation in growth trajectories and plant traits when grown along a 1000-m altitudinal gradient in Northern Italy, and under different temperature conditions in the growth chamber (from 14/18 °C to 26/30 °C, night/day), using a non-liner modeling approach. Under field conditions, traits related to plant height (maximum height, stem height, number of internodes) followed a three-parameter logistic curve. In contrast, leaf traits (lateral spread, number of leaves, leaf length and width) followed non-monotonic double-Richards curves that captured the decline patterns evident in the data. Plants grew faster, reaching a higher maximum plant height, and produced more biomass when grown at intermediate elevations. Under laboratory conditions, plants exhibited the same general growth trajectory of field conditions. However, leaf width did not show the recession after the maximum value shown by plants grown in the field, although the growth trajectories of some individuals, particularly those grown at 18 °C, showed a decline at late times. In addition, the plants grown at lower temperatures exhibited the highest value of biomass and preserved reproductive performances (e.g., amount of male inflorescence, pollen weight). From our findings, common ragweed exhibits a high phenotypic plasticity of vegetative and reproductive traits in response to different altitudes and temperature conditions. Under climate warming, this plasticity may facilitate the shift of the species towards higher elevation, but also the in situ resistance and (pre)adaptation of populations currently abundant at low elevations in the invasive European range. Such results may be also relevant for projecting the species management such as the impact by possible biocontrol agents.
Identification of Flavonoids in the Leaves of Eranthis longistipitata (Ranunculaceae) by Liquid Chromatography with High-Resolution Mass Spectrometry (LC-HRMS)
Authors: Kostikova Vera A. , Chernonosov Alexander A. , Kuznetsov Alexander A. , Petrova Natalia V. , Krivenko Denis A. , Chernysheva Olga A. , Wang Wei , Erst Andrey S.
Published: October 2021

Eranthis longistipitata Regel is an endemic plant of Central Asia. The flavonoid profile of E. longistipitata leaves was studied by mass spectrometry for the first time (natural populations of Kyrgyzstan and Uzbekistan, in 70% aqueous–ethanol extracts by liquid chromatography coupled with high-resolution mass spectrometry). Mass spectrometry revealed 18 flavonoid compounds. Flavonols featured the highest diversity, and 10 such substances were identified: 2 free aglycones (quercetin and kaempferol), 6 quercetin glycosides (peltatoside, hyperoside, reynoutrin, quercetin 3-sambubioside, rutin, and isoquercitrin), and 2 kaempferol glycosides (juglalin and trifolin). Two flavans (cianidanol and auriculoside), two hydroxyflavanones (6-methoxytaxifolin and aromadendrin), and one C-glycoside flavone—carlinoside—were identified. Dihydroxychalcones aspalathin, phloridzin, and phloretin were found too. Levels of rutin, quercetin, kaempferol, and hyperoside were confirmed by means of standards and high-performance liquid chromatography. Rutin concentration was the highest among all other identified flavonoid compounds: in the leaf samples from Kyrgyzstan, it ranged from 2.46 to 3.20 mg/g, and in those from Uzbekistan, from 1.50 to 3.01 mg/g. The diversity of flavonoid compounds in E. longistipitata leaves is probably due to external ecological and geographic factors and adaptive mechanisms.
Implementation and Characterization of a Laminate Hybrid Composite Based on Palm Tree and Glass Fibers
Authors: Kaddami Hamid , Arrakhiz Fatima-ezzahra , Hafs Oumaima , Assimi Taha , Boulafrouh Lamia , Ablouh El-Houssaine , Mansori Mohamed , Banouni Hicham , Bouzit Said , Erchiqui Fouad , Benmoussa Khalid
Published: October 2021

In this work, laminated polyester thermoset composites based on palm tree fibers extracted from palms leaflets and glass mats fibers were manufactured to develop hybrid compositions with good mechanical properties; the mixture of fibers was elaborated to not exceed 25 vol.%. Samples were prepared with a resin transfer molding (RTM) method and mechanically characterized using tensile and flexural, hardness, and impact tests, and ultrasonic waves as a non-destructive technique. The water sorption of these composite materials was carried out in addition to solar irradiation aging for approximately 300 days to predict the applicability and the long-term performance of the manufactured composites. Results have shown that the use of glass fibers significantly increased all properties; however, an optimum combination of the mixture could be interesting and could be developed with less glass sheet and more natural fibers, which is the goal of this study. On the other hand, exposure to natural sunlight deteriorated the mechanical resistance of the neat resin after only 60 days, while the composites kept high mechanical resistance for 365 days of exposure.
Linear Dimensional Change and Ultimate Tensile Strength of Polyamide Materials for Denture Bases
Authors: Chuchulska Bozhana , Zlatev Stefan
Published: October 2021

The aim of the current study was to evaluate the dimensional changes and ultimate tensile strength in three polyamide materials for denture bases fabrication through injection molding, subjected to artificial aging and different storage conditions. A total of 333 test specimens fabricated from Biosens (BS; Perflex, Netanya, Israel), Bre.flex 2nd edition (BF; Bredent, Senden, Germany) and ThermoSens (TS; Vertex Dental B.V., Soesterberg, The Netherlands)—n = 111 per material—were equally divided into three groups (n = 37) based on different treatments and storage conditions. Test samples allocated to the “Control group” were not artificially aged and stored in water for 24 h. Both “Treatment 1 group” and “Treatment 2 group” were subjected to thermocycling, the former dehydrated and the latter stored in water between cycle-sets. Linear changes and ultimate tensile strength were measured and analyzed for storage condition and material influence on the outcome variables. A Welch ANOVA test with Games–Howell post-hoc analysis was used to compare the influence of treatments across different materials. Significant differences were found for all three included materials with p values ranging from <0.05 to <0.001 for linear dimensional changes. The magnitude of alterations varied and was large for BS (Perflex, Israel) (ω2 = 0.62) and BF (Bredent, Germany) (ω2 = 0.47) and small but significant for TS (Vertex Dental B.V., The Netherlands) (ω2 = 0.05). However, results seem to fall into clinically acceptable range. Significant differences were also observed for the ultimate tensile strength test with the same range of p-values. All three materials showed different initial ultimate tensile strengths and varying reaction to artificial aging and storage with the lowest alterations observed for BF (Bredent, Germany) (ω2 = 0.05). Within the limitation of this study, it can be concluded that all three materials show different dimensional and mechanical properties when subjected to artificial aging and different storage. Although linear dimensions show significant changes, they seem to be clinically irrelevant, whereas the change in ultimate tensile strength after only 6-month equivalent clinical use was substantial for BS (Perflex, Israel) and TS (Vertex Dental B.V., The Netherlands).
Radiation Graft-Copolymerization of Ultrafine Fully Vulcanized Powdered Natural Rubber: Effects of Styrene and Acrylonitrile Contents on Thermal Stability
Authors: Rimdusit Niratchaporn , Jubsilp Chanchira , Mora Phattarin , Hemvichian Kasinee , Thuy Tran Thi , Karagiannidis Panagiotis , Rimdusit Sarawut
Published: October 2021

Graft copolymers, deproteinized natural rubber-graft-polystyrene (DPNR-g-PS) and deproteinized natural rubber-graft-polyacrylonitrile (DPNR-g-PAN), were prepared by the grafting of styrene (St) or acrylonitrile (AN) monomers onto DPNR latex via emulsion copolymerization. Then, ultrafine fully vulcanized powdered natural rubbers (UFPNRs) were produced by electron beam irradiation of the graft copolymers in the presence of di-trimethylolpropane tetra-acrylate (DTMPTA) as a crosslinking agent and, subsequently, a fast spray drying process. The effects of St or AN monomer contents and the radiation doses on the chemical structure, thermal stability, and physical properties of the graft copolymers and UFPNRs were investigated. The results showed that solvent resistance and grafting efficiency of DPNR-g-PS and DPNR-g-PAN were enhanced with increasing monomer content. SEM morphology of the UFPNRs showed separated and much less agglomerated particles with an average size about 6 μm. Therefore, it is possible that the developed UFPNRs grafted copolymers with good solvent resistance and rather high thermal stability can be used easily as toughening modifiers for polymers and their composites.
Superior Gas Barrier Properties of Biodegradable PBST vs. PBAT Copolyesters: A Comparative Study
Authors: Qin Pengkai , Wu Linbo , Li Bogeng , Li Naixiang , Pan Xiaohu , Dai Junming
Published: October 2021

As a bio-based counterpart of poly(butylene adipate-co-terephthalate) (PBAT), the well-known commercially available biodegradable aliphatic-aromatic copolyester, poly(butylene succinate-co-terephthalate) (PBST) has comparable physical and mechanical properties, but its gas barrier properties, which are very important for packaging material and mulch film applications, have not yet been reported in literature. In this paper, the O2, CO2 and water vapor barrier properties of PBST vs. PBAT were comparatively studied and reported for the first time. Theoretical calculation of O2 and CO2 permeation coefficients via group contribution method was also conducted. The barrier properties of PBST show clear copolymer composition dependence due to different contribution of BS and BT repeat units and composition-dependent crystallinity. Comparing with PBAT, PBST with close copolymer and three-phase (crystalline, amorphous, rigid amorphous) compositions shows 3.5 times O2 and CO2 and 1.5 times water vapor barrier properties. The slower segment movement and less free volume of PBST, and therefore slower gas diffusion in PBST, accounts for its superior O2 and CO2 barrier, while the better hydrophilicity of PBST counteracts partial contribution of slower segment movement so that the improvement in water vapor barrier is not as high as in O2 and CO2 barrier.
Ethyl Cellulose and Hydroxypropyl Methyl Cellulose Blended Methotrexate-Loaded Transdermal Patches: In Vitro and Ex Vivo
Authors: Latif Muhammad Shahid , Azad Abul Kalam , Nawaz Asif , Rashid Sheikh Abdur , Rahman Md. Habibur , Al Omar Suliman Y. , Bungau Simona G. , Aleya Lotfi , Abdel-Daim Mohamed M.
Published: October 2021

Transdermal drug delivery systems (TDDSs) have become innovative, fascinating drug delivery methods intended for skin application to achieve systemic effects. TDDSs overcome the drawbacks associated with oral and parenteral routes of drug administration. The current investigation aimed to design, evaluate and optimize methotrexate (MTX)-loaded transdermal-type patches having ethyl cellulose (EC) and hydroxypropyl methyl cellulose (HPMC) at different concentrations for the local management of psoriasis. In vitro release and ex vivo permeation studies were carried out for the formulated patches. Various formulations (F1–F9) were developed using different concentrations of HPMC and EC. The F1 formulation having a 1:1 polymer concentration ratio served as the control formulation. ATR–FTIR analysis was performed to study drug–polymer interactions, and it was found that the drug and polymers were compatible with each other. The formulated patches were further investigated for their physicochemical parameters, in vitro release and ex vivo diffusion characteristics. Different parameters, such as surface pH, physical appearance, thickness, weight uniformity, percent moisture absorption, percent moisture loss, folding endurance, skin irritation, stability and drug content uniformity, were studied. From the hydrophilic mixture, it was observed that viscosity has a direct influence on drug release. Among all formulated patches, the F5 formulation exhibited 82.71% drug release in a sustained-release fashion and followed an anomalous non-Fickian diffusion. The permeation data of the F5 formulation exhibited about a 36.55% cumulative amount of percent drug permeated. The skin showed high retention for the F5 formulation (15.1%). The stability study indicated that all prepared formulations had very good stability for a period of 180 days. Therefore, it was concluded from the present study that methotrexate-loaded transdermal patches with EC and HPMC as polymers at different concentrations suit TDDSs ideally and improve patient compliance for the local management of psoriasis.
Cost-Normalized Circular Economy Indicator and Its Application to Post-Consumer Plastic Packaging Waste
Authors: Tashkeel Rafay , Rajarathnam Gobinath P. , Wan Wallis , Soltani Behdad , Abbas Ali
Published: October 2021

This work presents an adaptation of the material circularity indicator (MCI) that incorporates economic consideration. The Ellen MacArthur Foundation (EMF) has developed the MCI to characterize the sustainability, viz., the “circularity”, of a product by utilizing life cycle assessment data of a product range rather than a single product unit. Our new “circo-economic” indicator (MCIE), combines product MCI in relation to total product mass, with a cost-normalization against estimated plastic recycling costs, for both separately collected and municipal solid waste. This is applied to assess Dutch post-consumer plastic packaging waste comprising polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), film, and mixed plastic products. Results show that MCIE of separate plastic collection (0.81) exceeds municipal solid waste (0.73) for most plastics, thus suggesting that under cost normalization, there is greater conformity of separately collected washed and milled goods to the circular economy. Cost sensitivity analyses show that improvements in plastic sorting technology and policy incentives that enable the production of MSW washed and milled goods at levels comparable to their separately collected counterparts may significantly improve their MCI. We highlight data policy changes and industry collaboration as key to enhanced circularity—emphasized by the restrictive nature of current Dutch policy regarding the release of plastic production, recycling, and costing data, with a general industry reluctance against market integration of weight-benchmarked recycled plastics.
Effect of a Natural Processing Aid on the Properties of Acrylonitrile-Butadiene Rubber: Study on Soybean Oil Fatty Acid from Seed Crop
Authors: Nun-Anan Phattarawadee , Hayichelaeh Chesidi , Boonkerd Kanoktip
Published: October 2021

For the industrial production of rubber, one of the key ingredients is a processing aid. It not only facilitates the processability but also tunes the final properties of the resultant rubber. In general, for a polar rubber like acrylonitrile-butadiene rubber (NBR), the processing aids earning the most attention are synthesized from petroleum, such as dioctyl phthalate (DOP). However, due to their toxicity, many rubber chemists have tried to find alternative chemicals that are environmentally friendly and derived from a renewable resource. In this research, we investigated the effects of the soybean oil fatty acid (SBOFA), synthesized in house via hydrolysis of SBO, on the properties of NBR in comparison with DOP. Initially, it was found that the addition of SBOFA improved the flowability of the NBR compound, as indicated by the progressive decrease in the Mooney viscosity with increasing levels of SBOFA. The results from various techniques indicated that the crosslink density of the NBR vulcanizates passed through the maximum at the SBOFA loading of 4 phr. Upon loading SBOFA up to 4 phr, there was no significant deterioration in the mechanical strength of the SBOFA-plasticized NBR vulcanizates. Typically, the presence of SBOFA at 4 phr enhanced the thermal resistance of the NBR vulcanizate by shifting the thermal decomposition to a higher temperature. At a given loading, it was found that the SBOFA-plasticized NBR vulcanizate showed a comparable plasticizing efficiency and mechanical strength with the DOP-plasticized one. The result from this study shows that SBOFA is a good alternative sustainable eco-friendly processing aid to use for NBR.
Liquid Crystals Investigation Behavior on Azo-Based Compounds: A Review
Authors: Razali Nurul Asma , Jamain Zuhair
Published: October 2021

Liquid crystal is an intermediate phase between the crystalline solid and an isotropic liquid, a very common substance in our daily lives. Two major classes of liquid crystal are lyotropic, where a liquid crystal is dissolved in a specific solvent under a particular concentration and thermotropic, which can be observed under temperature difference. This review aims to understand how a structure of a certain azo compound might influence the liquid crystal properties. A few factors influence the formation of different liquid crystals: the length of the alkyl terminal chain, inter/intra-molecular interaction, presence of spacer, spacer length, polarization effects, odd-even effects, and the presence of an electron-withdrawing group or an electron-donating group. As final observations, we show the compound’s different factors, the other liquid crystal is exhibited, and the structure–property relationship is explained. Liquid crystal technology is an ideal system to be applied to products to maximize their use, especially in the electronic and medical areas.
Solvent Effect in Imidazole-Based Poly(Ionic liquid) Membranes: Energy Storage and Sensing
Authors: Kesküla Arko , Peikolainen Anna-Liisa , Kilmartin Paul A. , Kiefer Rudolf
Published: October 2021

Polymerized ionic liquids (PILs) are interesting new materials in sustainable technologies for energy storage and for gas sensor devices, and they provide high ion conductivity as solid polymer electrolytes in batteries. We introduce here the effect of polar protic (aqueous) and polar aprotic (propylene carbonate, PC) electrolytes, with the same concentration of lithium bis(trifluoromethane) sulfonimide (LiTFSI) on hydrophobic PIL films. Cyclic voltammetry, scanning ionic conductance microscopy and square wave voltammetry were performed, revealing that the PIL films had better electroactivity in the aqueous electrolyte and three times higher ion conductivity was obtained from electrochemical impedance spectroscopy measurements. Their energy storage capability was investigated with chronopotentiometric measurements, and it revealed 1.6 times higher specific capacitance in the aqueous electrolyte as well as novel sensor properties regarding the applied solvents. The PIL films were characterized with scanning electron microscopy, energy dispersive X-ray, FTIR and solid state nuclear magnetic resonance spectroscopy.
H+-Conducting Aromatic Multiblock Copolymer and Blend Membranes and Their Application in PEM Electrolysis
Authors: Bender Johannes , Mayerhöfer Britta , Trinke Patrick , Bensmann Boris , Hanke-Rauschenbach Richard , Krajinovic Katica , Thiele Simon , Kerres Jochen
Published: October 2021

As an alternative to common perfluorosulfonic acid-based polyelectrolytes, we present the synthesis and characterization of proton exchange membranes based on two different concepts: (i) Covalently bound multiblock-co-ionomers with a nanophase-separated structure exhibit tunable properties depending on hydrophilic and hydrophobic components’ ratios. Here, the blocks were synthesized individually via step-growth polycondensation from either partially fluorinated or sulfonated aromatic monomers. (ii) Ionically crosslinked blend membranes of partially fluorinated polybenzimidazole and pyridine side-chain-modified polysulfones combine the hydrophilic component’s high proton conductivities with high mechanical stability established by the hydrophobic components. In addition to the polymer synthesis, membrane preparation, and thorough characterization of the obtained materials, hydrogen permeability is determined using linear sweep voltammetry. Furthermore, initial in situ tests in a PEM electrolysis cell show promising cell performance, which can be increased by optimizing electrodes with regard to binders for the respective membrane material.
Aspects of In Vitro Biodegradation of Hybrid Fibrin–Collagen Scaffolds
Authors: Egorikhina Marfa N. , Bronnikova Irina I. , Rubtsova Yulia P. , Charykova Irina N. , Bugrova Marina L. , Linkova Daria D. , Aleynik Diana Ya.
Published: October 2021

The success of the regenerative process resulting from the implantation of a scaffold or a tissue-engineered structure into damaged tissues depends on a series of factors, including, crucially, the biodegradability of the implanted materials. The selection of a scaffold with appropriate biodegradation characteristics allows for synchronization of the degradation of the construct with the processes involved in new tissue formation. Thus, it is extremely important to characterize the biodegradation properties of potential scaffold materials at the stage of in vitro studies. We have analyzed the biodegradation of hybrid fibrin–collagen scaffolds in both PBS solution and in trypsin solution and this has enabled us to describe the processes of both their passive and enzymatic degradation. It was found that the specific origin of the collagen used to form part of the hybrid scaffolds could have a significant effect on the nature of the biodegradation process. It was also established, during comparative studies of acellular scaffolds and scaffolds containing stem cells, that the cells, too, make a significant contribution to changes in the biodegradation and structural properties of such scaffolds. The study results also provided evidence indicating the dependency between the pre-cultivation period for the cellular scaffolds and the speed and extent of their subsequent biodegradation. Our discussion of results includes an attempt to explain the mechanisms of the changes found. We hope that the said results will make a significant contribution to the understanding of the processes affecting the differences in the biodegradation properties of hybrid, biopolymer, and hydrogel scaffolds.
The Crystallisation, Microphase Separation and Mechanical Properties of the Mixture of Ether-Based TPU with Different Ester-Based TPUs
Authors: Que Yu-Hui , Shi Ying , Liu Li-Zhi , Wang Yuan-Xia , Wang Chen-Chen , Zhang Hai-Chao , Han Xu-Yang
Published: October 2021

The difference in compatibility at the molecular level can lead to a change of microphase separation structure of thermoplastic polyurethanes blend systems, which will improve their thermal and mechanical properties. In this study, TDI-polyester based TPU was blended with MDI-polyether-based TPU and MDI-polyester based TPU, with different ratios. In the blend system, the obvious reduction of the melting temperature of the high-temperature TDI-polyester based TPU component indicates its hard segments can be mutually integrated with the other component. For TDI-polyester based TPU/MDI-polyether based TPU blends, their similar hard segment ratio and similar chemical structure of the soft segment give the molecular chains of the two components better compatibility. The aggregation structure of the two kinds of chains can rearrange at the molecular level which makes the hard domains mutually integrate to form a new phase separation structure with larger phase region distance. As a result, the yield strength of this blend increased by almost 143% when the elongation at break was only reduced by 12%. In contrast, the other group of blends still partly maintain their respective micro domains, forming a weak interface and leading to a decreased of elongation at break.
3D Printing of Customized Aspheric Lenses for Imaging
Authors: Zhu Dexing , Zhang Jian , Xu Qiao , Li Yaguo
Published: October 2021

A simple and efficient process for fabricating customized aspheric lenses is reported, in which a stereolithographic 3D printer combined with the meniscus equilibrium post-curing technique is employed. Two kinds of UV-curable resins, DentaClear and HEMA, were used for printing aspheric lenses in our experiments. The printed DentaClear lens featured low surface profile deviation of ~74 μm and showed satisfactory optical imaging resolution of 50.80 lp/mm, i.e., 4.92 μm. The surface roughness of the printed lens with DentaClear was measured to be around 2 nm with AFM. The surface roughness was improved as a result of post-curing, which reduced the ripples on printed lens surfaces. In contrast, the printed HEMA lens exhibited a significant stair-stepping effect with a large surface profile deviation of ~150 μm. The ripples were somewhat apparent even if the printed HEMA lens surface was smoothed by means of post-curing. No sharp image can be obtained with the HEMA lens in the resolution testing. The composition of HEMA resin may be the reason for the relatively poor surface quality and optical properties.
Interaction between the Standard and the Measurement Instrument during the Flow Velocity Sensor Calibration Process
Authors: Jamróz Paweł
Published: October 2021

The complex ventilation system development process is associated with the stages of modelling, design, execution, and testing. Each of these steps requires the use of measuring equipment that is capable of determining the basic parameters of the flow. In the process of calibrating instruments for measuring flow velocity, one of the limitations is the size of the calibrated devices positioned in the test section of the wind tunnel. This is related to the change in the flow condition within the vicinity of the calibrated anemometers, which is caused by the blockage effect. Instruments with significant dimensions in relation to the cross-sectional area of the wind tunnel test section may have an impact on the reference velocity as indicated by the standard. In such cases, the calibration results may be affected by additional systematic error. This article presents a study of this effect using a real case of a calibration laboratory and commonly used sensors. The influence of different types of air velocity sensors on velocity profiles in the measurement standard area is also investigated. Additionally, the area of the blockage effect is described. The obtained results indicate the possibility of a proper placement for the measuring standard due to minimization of the flow-blocking effect.
Fortes in Fide—The Role of Faith in the Heroic Struggle against Communism
Authors: Rončáková Terézia
Published: October 2021

Repression and persecution by the totalitarian communist regimes have significantly affected the fates of Christian churches and believers in the countries of the “Eastern Bloc”. Many members of the clergy and laypersons were incarcerated, tortured and persecuted, several bishops suffered exemplary punishment in the propaganda-driven show trials and a few of them were later beatified or canonized across the world (by the Catholic Church). Focusing on the literature originating in Slovakia, this meta-report aimed to summarize the key authors’ essential works and to examine the question as to whether—and to what extent—faith was a contributing factor in the collapse of the communist regime. What was the role of the churches and believers in the struggle against communism? How and to what extent believers were involved in the resistance movements and the political and economic transformation of their countries that were set in motion by the collapse of those regimes? Based on an analysis of hundreds of books and articles on the subject, essential ideas were extracted, categorized and presented. The works of the persecuted authors were the subject of a detailed qualitative content analysis. Thus, four overarching dimensions (philosophical, intimate, personal and social/political) and fourteen categories related to the experience of faith were identified.
Moral Virtue as a Requisite for Illumination in the Platonic Tradition
Authors: Sheeley Kristian
Published: October 2021

This paper traces the development of the idea that we must cultivate moral virtue in order to attain some degree of illumination regarding the nature of reality. I use the term “illumination” to cover a range of meanings intended by the philosophers I discuss, such as the “acquisition of wisdom” (Phaedo, 65a), the “sight” of divine beauty (Symposium, 210d–212b), or a mystical experience involving God or divine reality. Although this theme appears in many texts from the Platonic tradition, I focus on three major stages of its development. First, I show how Plato provides the basic framework of the idea that moral virtue is necessary for illumination, especially in his Phaedo and Symposium. Then, I explain how Plotinus synthesizes and substantially develops Plato’s discussions of this idea. Finally, I discuss the Cappadocian Fathers’ (Basil of Caesarea, Gregory of Nyssa, and Gregory Nazianzen) Christianization of this Platonic theme. In other words, Plotinus develops the basic framework of this argument first set forth by Plato, and the Cappadocians then adapt and modify Plotinus’ views to fit their Christian commitments.