bluuebunny/crossref_metadata_2025 huggingface dataset:
Safety of Dietary Camelina Oil Supplementation in Healthy, Adult Dogs
Authors: Burron Scarlett , Richards Taylor , Patterson Keely , Grant Caitlin , Akhtar Nadeem , Trevizan Luciano , Pearson Wendy , Shoveller Anna Kate
Published: September 2021

This study aimed to determine whether camelina oil is safe for use in canine diets, using canola oil and flax oil as controls, as they are similar and generally regarded as safe (GRAS) for canine diets. A total of thirty privately-owned adult dogs of various breeds (17 females; 13 males), with an average age of 7.2 ± 3.1 years (mean ± SD) and a body weight (BW) of 27.4 ± 14.0 kg were used. After a 4-week wash-in period using sunflower oil and kibble, the dogs were blocked by breed, age, and size and were randomly allocated to one of three treatment oils (camelina (CAM), flax (FLX), or canola (OLA)) at a level of 8.2 g oil/100 g total dietary intake. Body condition score (BCS), BW, food intake (FI), and hematological and select biochemical parameters were measured at various timepoints over a 16-week feeding period. All of the data were analyzed with ANOVA using the PROC GLIMMIX of SAS. No biologically significant differences were seen between the treatment groups in terms of BW, BCS, FI, and hematological and biochemical results. Statistically significant differences noted among some serum biochemical results were considered small and were due to normal biological variation. These results support the conclusion that camelina oil is safe for use in canine nutrition.
Reproductive Performance of Hycole Rabbit Does, Growth of Kits and Milk Chemical Composition during Nine Consecutive Lactations under Extensive Rhythm
Authors: Ludwiczak Agnieszka , Składanowska-Baryza Joanna , Kuczyńska Beata , Sell-Kubiak Ewa , Stanisz Marek
Published: September 2021

The goal of this study was to analyze the reproductive performance of does, growth of their kits, and chemical composition of their milk over nine consecutive parities in order to indicate the boundary of female reproductive profitability. The novelty of this study results from the combinations of three factors: extensive reproductive rhythm, commercial farming conditions, and a period of nine consecutive parities, showing the actual lifespan of a rabbit doe on commercial farms. The data was collected on 60 Hycole females kept at a commercial rabbit farm. Throughout the study, 32 does were excluded due to different reasons (e.g., excluded by means of selection—43.8% and mortalities—25.0%). The does were first inseminated at 28 weeks of age. Following artificial inseminations were conducted 14–15 days after each parturition. All kits were weaned at the age of 35 days. The following characteristics were analysed: body weight of rabbit does at artificial insemination, milk production per lactation, litter size, litter weight, average kit weight, and milk chemical composition. Rabbit does had a significant decrease in kindling rate between the eighth and the ninth parity (by 10.0 percentage points; p = 0.039). The litter size at weaning in the ninth parity was significantly lower to litters weaned at other analysed parities. The amount of milk produced per lactation was affected by the parity order (6.31–6.76 kg; p = 0.042). The litter weights on day 21 and 35 were the lowest at ninth parity. The content of total solids (TS), solids-not-fat, and fat was affected by the parity order on both analysed lactation days. The content of TS and fat in rabbit milk was characterized with a decreasing trend over the analysed period, on both lactation days. The results clearly indicate that rabbit does under extensive reproductive cycles characterize with a very good reproductive performance and can be successfully used for reproduction even up to the eighth parity. However, further research is needed if keeping them longer will not be profitable.
The First Report of mcr-1-Carrying Escherichia coli Originating from Animals in Serbia
Authors: Mišić Dušan , Kiskaroly Ferenc , Szostak Michael P. , Cabal Adriana , Ruppitsch Werner , Bernreiter-Hofer Tanja , Milovanovic Viktoria , Feßler Andrea T. , Allerberger Franz , Spergser Joachim , Müller Elke , Schwarz Stefan , Braun Sascha D. , Monecke Stefan , Ehricht Ralf , Korus Maciej , Benković Damir , Korzeniowska Malgorzata , Loncaric Igor
Published: September 2021

The aim of this study was continuous monitoring of the presence of mcr-1 to mcr-5 genes in Enterobacterales isolated from cattle, pigs, and domestic poultry at intensive breeding facilities in Northern Vojvodina, Serbia, from 1 January 1 to 1 October 2020. Out of 2167 examined samples, mcr-1 was observed in five E. coli isolates originating from healthy turkeys. Four isolates belonged to the phylogenetic group B1, and one isolate to the phylogenetic group A. Detected E. coli serogenotypes (somatic O and flagellar H antigens) were O8:H25 and O29:H25. Core-genome multi-locus sequence typing (cgMLST) revealed three ST58 isolates clustering together in Clonal Complex (CC) 155 and two singletons of ST641-CC86 and ST410-CC23, respectively. Clonotyping revealed CH4-32 (n = 3), CH6-53 (n = 1) and CH4-24 (n = 1). In all isolates, the mcr-1 gene was located on a large IncX4 replicon type plasmid. Eight virulence-associated genes (VAGs) typical of avian pathogenic E. coli (APEC) (fyuA, fimH, hlyF, iss, ompT, sitA, traT, iroN) were detected in four isolates. These isolates were investigated for susceptibility to four biocides and revealed MIC values of 0.125% for glutardialdehyde, of 0.00003–0.00006% for chlorohexidine, of 4–6% for isopropanol and of 0.001–0.002% for benzalkonium chloride. All obtained MIC values of the tested biocides were comparable to the reference strain, with no indication of possible resistance. This is the first report of mcr-1.1-carrying E. coli from Serbia. Although only samples from turkeys were mcr-positive in this study, continuous monitoring of livestock samples is advised to prevent a spill-over from animals to humans.
Hospital Wastewater—Source of Specific Micropollutants, Antibiotic-Resistant Microorganisms, Viruses, and Their Elimination
Authors: Mackuľak Tomáš , Cverenkárová Klára , Vojs Staňová Andrea , Fehér Miroslav , Tamáš Michal , Škulcová Andrea Bútor , Gál Miroslav , Naumowicz Monika , Špalková Viera , Bírošová Lucia
Published: September 2021

Municipal wastewaters can generally provide real-time information on drug consumption, the incidence of specific diseases, or establish exposure to certain agents and determine some lifestyle consequences. From this point of view, wastewater-based epidemiology represents a modern diagnostic tool for describing the health status of a certain part of the population in a specific region. Hospital wastewater is a complex mixture of pharmaceuticals, illegal drugs, and their metabolites as well as different susceptible and antibiotic-resistant microorganisms, including viruses. Many studies pointed out that wastewater from healthcare facilities (including hospital wastewater), significantly contributes to higher loads of micropollutants, including bacteria and viruses, in municipal wastewater. In addition, such a mixture can increase the selective pressure on bacteria, thus contributing to the development and dissemination of antimicrobial resistance. Because many pharmaceuticals, drugs, and microorganisms can pass through wastewater treatment plants without any significant change in their structure and toxicity and enter surface waters, treatment technologies need to be improved. This short review summarizes the recent knowledge from studies on micropollutants, pathogens, antibiotic-resistant bacteria, and viruses (including SARS-CoV-2) in wastewater from healthcare facilities. It also proposes several possibilities for improving the wastewater treatment process in terms of efficiency as well as economy.
D-Mannoside FimH Inhibitors as Non-Antibiotic Alternatives for Uropathogenic Escherichia coli
Authors: Montes-Robledo Alfredo , Baldiris-Avila Rosa , Galindo Johan Fabian
Published: September 2021

FimH is a type I fimbria of uropathogenic Escherichia coli (UPEC), recognized for its ability to adhere and infect epithelial urinary tissue. Due to its role in the virulence of UPEC, several therapeutic strategies have focused on the study of FimH, including vaccines, mannosides, and molecules that inhibit their assembly. This work has focused on the ability of a set of monosubstituted and disubstituted phenyl mannosides to inhibit FimH. To determine the 3D structure of FimH for our in silico studies, we obtained fifteen sequences by PCR amplification of the fimH gene from 102 UPEC isolates. The fimH sequences in BLAST had a high homology (97–100%) to our UPEC fimH sequences. A search for the three-dimensional crystallographic structure of FimH proteins in the PDB server showed that proteins 4X5P and 4XO9 were found in 10 of the 15 isolates, presenting a 67% influx among our UPEC isolates. We focused on these two proteins to study the stability, free energy, and the interactions with different mannoside ligands. We found that the interactions with the residues of aspartic acid (ASP 54) and glutamine (GLN 133) were significant to the binding stability. The ligands assessed demonstrated high binding affinity and stability with the lectin domain of FimH proteins during the molecular dynamic simulations, based on MM-PBSA analysis. Therefore, our results suggest the potential utility of phenyl mannoside derivatives as FimH inhibitors to mitigate urinary tract infections produced by UPEC; thus, decreasing colonization, disease burden, and the costs of medical care.
Efflux Pump Inhibition and Resistance Modulation in Mycobacterium smegmatis by Peucedanum ostruthium and Its Coumarins
Authors: Šimunović Katarina , Solnier Julia , Alperth Fabian , Kunert Olaf , Smole Možina Sonja Smole , Bucar Franz
Published: September 2021

Antibiotic resistance is a growing problem and may become the next major global health crisis if no timely actions are taken. Mycobacterial infections are widespread and, due to antibiotic resistance, also hard to treat and a major cause of mortality. Natural compounds have the potential to increase antibiotic effectiveness due to their resistance modulatory and antimicrobial effects. In this study, Peucedanum ostruthium extracts, fractions, and isolated compounds were investigated regarding their antimicrobial and resistance-modulatory effects as well as efflux pump inhibition in Mycobacterium smegmatis. P. ostruthium extracts were found to have anti-mycobacterial potential and resistance modulating effects on ethidium bromide activity. The major antibacterial effect was attributed to ostruthin, and we found that the more lipophilic the substrate, the greater the antimicrobial effect. Imperatorin caused potent modulatory effects by interfering with the action of the major LfrA efflux pump in M. smegmatis. The plant P. ostruthuim has a complex effect on M. smegmatis, including antibacterial, efflux pump inhibition, resistance modulation, and membrane permeabilization, and its major constituents, ostruthin and imperatorin, have a distinct role in these effects. This makes P. ostruthium and its coumarins promising therapeutics to consider in the fight against drug-resistant mycobacteria.
Cationic Polymer-Coated Magnetic Nanoparticles with Antibacterial Properties: Synthesis and In Vitro Characterization
Authors: Shatan Anastasiia B. , Patsula Vitalii , Dydowiczová Aneta , Gunár Kristýna , Velychkivska Nadiia , Hromádková Jiřina , Petrovský Eduard , Horák Daniel
Published: September 2021

Uniformly sized magnetite nanoparticles (Dn = 16 nm) were prepared by a thermal decomposition of Fe(III) oleate in octadec-1-ene and stabilized by oleic acid. The particles were coated with Sipomer PAM-200 containing both phosphate and methacrylic groups available for the attachment to the iron oxide and at the same time enabling (co)polymerization of 2-(dimethylamino)ethyl methacrylate and/or 2-tert-butylaminoethyl methacrylate at two molar ratios. The poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) and poly[2-(dimethylamino)ethyl methacrylate-co-2-tert-butylaminoethyl methacrylate] [P(DMAEMA-TBAEMA)] polymers and the particles were characterized by 1H NMR spectroscopy, size-exclusion chromatography, transmission electron microscopy, dynamic light scattering, thermogravimetric analysis, magnetometry, and ATR FTIR and atomic absorption spectroscopy. The antimicrobial effect of cationic polymer-coated magnetite nanoparticles tested on both Escherichia coli and Staphylococcus aureus bacteria was found to be time- and dose-responsive. The P(DMAEMA-TBAEMA)-coated magnetite particles possessed superior biocidal properties compared to those of P(DMAEMA)-coated one.
Effectiveness of an Electronic Automated Antibiotic Time Out Alert in the Setting of Gram-Negative Bacteremia
Authors: Mohayya Sana M. , Narayanan Navaneeth , Cimilluca Daniel , Malanowski Alexander , Vaidya Parth , Bhowmick Tanaya
Published: September 2021

To minimize complications associated with over-utilization of antibiotics, many antimicrobial stewardship programs have incorporated an antibiotic time out (ATO); however, limited data are available to support its effectiveness. This was a single-center retrospective cohort study assessing the impact of the automated electronic ATO in the setting of Gram-negative bacteremia. The primary outcome was the proportion of patients who received a modification of therapy within 24 h of final culture results. Secondary outcomes included modification at any point in therapy, time to modification of therapy, time to de-escalation, and days of therapy of broad-spectrum antibiotics. There was a total of 222 patients who met inclusion criteria, 97 patients pre-ATO and 125 patients post-ATO. The primary outcome of modification of therapy within 24 h of final culture results was not significantly different (24% vs. 30%, p = 0.33). The secondary outcome of modification of therapy at any point in therapy was not significantly different between the two groups (65% vs. 67%, p = 0.73). All other secondary outcomes were not significantly different. The ATO alert was not associated with a higher rate of antibiotic modification within 24 h of culture results in patients with GNB. Further efforts are needed to optimize the ATO strategy and antibiotic prescribing practices.
Nano-Curcumin Prevents Cardiac Injury, Oxidative Stress and Inflammation, and Modulates TLR4/NF-κB and MAPK Signaling in Copper Sulfate-Intoxicated Rats
Authors: Sarawi Wedad S. , Alhusaini Ahlam M. , Fadda Laila M. , Alomar Hatun A. , Albaker Awatif B. , Aljrboa Amjad S. , Alotaibi Areej M. , Hasan Iman H. , Mahmoud Ayman M.
Published: September 2021

Copper (Cu) is essential for a plethora of biological processes; however, its high redox reactivity renders it potentially toxic. This study investigated the protective effect of curcumin (CUR) and nano-CUR (N-CUR) against Cu cardiotoxicity, emphasizing the role of oxidative stress, TLR4/NF-κB and mitogen-activated protein kinase (MAPK) signaling and cell death in rats. Rats received 100 mg/kg copper sulfate (CuSO4), a pesticide used for repelling pests, and were concurrently treated with CUR or N-CUR for 7 days. Cu caused cardiac injury manifested by elevated serum cardiac troponin I (cTnI), creatine kinase (CK)-MB, and lactate dehydrogenase (LDH), as well as histopathological alterations. Cardiac malondialdehyde (MDA), NF-κB p65, TNF-α, and IL-6 were increased, and reduced glutathione (GSH), superoxide dismutase (SOD) and catalase were decreased in Cu-treated rats. CUR and N-CUR prevented cardiac tissue injury, decreased serum cTnI, CK-MB, and LDH, and cardiac MDA, NF-κB p65, TNF-α, and IL-6, and enhanced cellular antioxidants. CUR and N-CUR downregulated TLR4 and AP-1, and decreased the phosphorylation levels of p38 MAPK, JNK, and ERK1/2. In addition, CUR and N-CUR increased cardiac Bcl-2 and BAG-1, decreased Bax and caspase-3, and prevented DNA fragmentation. In conclusion, N-CUR prevents Cu cardiotoxicity by attenuating oxidative injury, inflammatory response, and apoptosis, and modulating TLR4/NF-κB and MAPK signaling. The cardioprotective effect of N-CUR was more potent than the native form.
Assessing the Potential of Nutraceuticals as Geroprotectors on Muscle Performance and Cognition in Aging Mice
Authors: Singlár Zoltán , Szentesi Péter , Fodor János , Angyal Ágnes , Csernoch László , Sztretye Mónika
Published: September 2021

Aging and frailty are associated with a decline in muscle force generation, which is a direct consequence of reduced muscle quantity and quality. Among the leading contributors to aging is the generation of reactive oxygen species, the byproducts of terminal oxidation. Their negative effects can be moderated via antioxidant supplementation. Krill oil and astaxanthin (AX) are nutraceuticals with a variety of health promoting, geroprotective, anti-inflammatory, anti-diabetic and anti-fatigue effects. In this work, we examined the functional effects of these two nutraceutical agents supplemented via pelleted chow in aging mice by examining in vivo and in vitro skeletal muscle function, along with aspects of intracellular and mitochondrial calcium homeostasis, as well as cognition and spatial memory. AX diet regimen limited weight gain compared to the control group; however, this phenomenon was not accompanied by muscle tissue mass decline. On the other hand, both AX and krill oil supplementation increased force production without altering calcium homeostasis during excitation-contraction coupling mechanism or mitochondrial calcium uptake processes. We also provide evidence of improved spatial memory and learning ability in aging mice because of krill oil supplementation. Taken together, our data favors the application of antioxidant nutraceuticals as geroprotectors to improve cognition and healthy aging by virtue of improved skeletal muscle force production.
Effect of γ-aminobutyric Acid on Phenolics Metabolism in Barley Seedlings under Low NaCl Treatment
Authors: Wang Mian , Zhu Yahui , Wang Pei , Gu Zhenxin , Yang Runqiang
Published: September 2021

It has been revealed that high NaCl stress (>60 mmol L−1) induced phenolics accumulation in barley seedlings, with γ-aminobutyric acid (GABA) playing a key role. Interestingly, low NaCl stimulus (20 mmol L−1) enhancing phenolics synthesis and growth of barley seedlings was also reported recently. Hence, exogenous GABA and its bio-synthesis inhibitor 3-mercaptopropionic acid (3-MP) were applied to reveal the mechanism of GABA regulating phenolics metabolism in barley seedlings treated with 20 mmol L−1 NaCl. The contents of total phenolics and flavonoids significantly increased by 11.64% and 14.52% under NaCl, respectively. The addition of GABA further increased phenolics and flavonoids contents, especially for gallic acid, protocatechuic acid, caffeic acid, and quercetin, compared with NaCl treatment. Simultaneously, GABA increased the activities and mRNA levels of phenylalanine ammonia lyase (PAL), cinnamic acid 4-hydroxylase (C4H), and 4-coumalyl CoA ligase (4CL). The addition of 3-MP suppressed the above effects, except for increasing the protein levels of PAL, C4H, and 4CL. Low concentration of NaCl not only promoted growth, but also stimulated endogenous GABA metabolism to affect key enzymes activities and mRNA levels for phenolics synthesis in barley seedlings.
Screening of the Honey Aroma as a Potential Essence for the Aromachology
Authors: Štefániková Jana , Martišová Patrícia , Šnirc Marek , Šedík Peter , Vietoris Vladimír
Published: September 2021

The aim of the study was to determine the aroma profiles of four kinds of Slovak honey (sunflower, honeydew, acacia, and linden) by a qualitative and quantitative screening of their volatile compounds and by gas chromatography for the potential use in the aromachology and the business sphere. The results showed that several unique volatiles were identified in one kind of honey, while they were not identified in the remaining ones. The acacia honey had the unique volatile linalool oxide (1.13–3.9%); linden honey had the unique volatiles nerol oxide (0.6–1.6%), ethyl esters (0.41–8.78%), lilac aldehyde D (6.6%), and acetophenone (0.37%). The honeydew honey had the unique volatiles santene (0.28%) and cyclofenchene (0.59–1.39%), whereas 2-bornene (0.43–0.81%) was typical for sunflower honey. While linden honey was characterized by fruity ethyl esters, honeydew honey had more monoterpenoid compounds. In the principal component analysis model, the four kinds of honey could not be differentiated by aroma volatiles. However, it was possible to classify the linden and sunflower honey using the LDA. In conclusion, the current study provided experimental evidence that the marker compounds from different kinds of honey might be promising candidates for production of inhaling aromas.
Pro-Pre and Postbiotic in Celiac Disease
Authors: Conte Mariangela , Porpora Monia , Nigro Federica , Nigro Roberto , Budelli Andrea Luigi , Barone M. Vittoria , Nanayakkara Merlin
Published: September 2021

Celiac Disease (CD) is an autoimmune disease characterized by inflammation of the intestinal mucosa due to an immune response to wheat gliadins. It presents in subjects with genetic susceptibility (HLA-DQ2/DQ8 positivity and non-HLA genes) and under the influence of environmental triggers, such as viral infections and intestinal microbiota dysbiosis. The only treatment currently available in CD is a gluten-free diet for life. Despite this, the intestinal dysbiosis that is recorded in celiac subjects persists, even with adherence to dietary therapy. In this review, we have analyzed the literature over the past several decades, which have focused on the use of pro-, pre- and post-biotics in vitro and in vivo in CD. The study of probiotics and their products in CD could be interesting for observing their various effects on several different pathways, including anti-inflammatory properties.
Influences of Organic Volatile Compounds on the Secondary Organic Carbon of Fine Particulate Matter in the Fruit Tree Area
Authors: Song Myoungki , Kim Minwook , Oh Sea-Ho , Park Chaehyeong , Kim Moonsu , Kim Minsung , Lee Hyunji , Choe Seoyeong , Bae Min-Suk
Published: September 2021

Three combined investigations were conducted to examine the sources of PM2.5 in agricultural areas. The first was the measurement of PM2.5 and gaseous compounds in the greenhouse, which is a relatively closed system, while the second was the analysis of pesticide components used in agricultural areas. Finally, the physical and chemical properties of PM2.5 were analyzed in an orchard area and compared with the results of the greenhouse and agricultural chemical analyses. As a result, this research was able to confirm the source of emission and characteristics of PM2.5 originating from the agricultural area. Volatile organic compounds (VOCs) in agricultural areas are emitted by agricultural chemicals, and the discharged agricultural chemicals are first absorbed into the soil, and then released into the air by evaporation. Finally, the secondary products of PM2.5 in agricultural areas were estimated to have positive relationships with the VOCs from agricultural chemicals, and NH3 from fertilizers. The photochemical reactions of VOCs and NH3 were responsible for the impact on secondary products.
MHD Flow and Heat Transfer of Hybrid Nanofluid over an Exponentially Shrinking Surface with Heat Source/Sink
Authors: Othman Mohamad Nizam , Jedi Alias , Bakar Nor Ashikin Abu
Published: September 2021

In nanotechnology research, nanofluid technology contributes many applications to engineering applications and industry, such as power generation, solar collection, heat exchangers for cooling, and many more. However, there are still a few constraints in terms of heat transfer enhancement, although nanofluid properties show the best heat transfer rate compared with conventional fluids. Thus, this study was conducted for the purpose of investigating the behaviors of flow and heat transfer of hybrid nanofluid with carbon nanotubes (CNTs) on a permeable exponentially shrinking surface, as well as investigating the effects of a magnetic field and heat source/sink. This study was conducted by developing a mathematical model, which was the Tiwari–Das model for momentum and energy equations, and then transforming the model’s partial differential equations (PDEs) to ordinary differential equations (ODEs) using a similarity solution. Next, these equations were solved numerically using the MATLAB bvp4c boundary value problem solver. The authors particularly explored these behaviors with a few variations. Based on the results obtained, it was found that dual solutions exist in a specific range of the shrinking case, λc<λ<−λ and that the critical point λc also exists in a range of −1.5 < λc < −1 with different parameters. For the heat source/sink effect, the Nusselt number was higher when heat sink case ε < 0, whereas it decreased when the heat source case ε > 0. Therefore, this study deduced that the heat transfer rate of hybrid nanofluid (CNTs/Cu–water) is better than regular nanofluid (CNT–water) and conventional fluid (water). The present study took into consideration the problem of MHD flow and heat transfer analysis of a hybrid nanofluid towards an exponentially shrinking surface with the presence of heat source/sink and thermal radiation effects. The authors show that dual solutions exist within a specific range of values due to the shrinking case. The current work is predicted to have numerous benefits in equivalent real-world systems.
Optimization of Acoustic Communication Links for a Swarm of AUVs: The COMET and NEMOSENS Examples
Authors: Gussen Camila M. G. , Laot Christophe , Socheleau François-Xavier , Zerr Benoît , Le Mézo Thomas , Bourdon Raphaël , Le Berre Céline
Published: September 2021

Underwater acoustic communication is a key point for performance improvement in an autonomous underwater vehicle (AUV) swarm. The communication process is essential for improving the AUVs localization accuracy for navigation and is a convenient way for sharing information among the AUVs in a network. The objective of this work, which was developed in the COMET and NEMOSENS projects, is to address the communication process required in a mobile underwater wireless network, with a focus on the proposal of an adaptive physical layer methodology. We discuss about the employed channel access method, the frame structure, and we propose the usage of an adaptive guard interval in order to ameliorate the network usage rate. We explain the physical layer aspect of the communication: the data processing at the transmitter and receiver side. In addition to that, we propose the usage of smart communications among AUVs. We design a method for adapting some physical layer parameters. The proposed approach relies only on the knowledge of the transmission geometry, and it optimizes the number of subcarriers and the cyclic-prefix length of the Orthogonal Frequency-Division Multiplexing (OFDM) system. The obtained results show a performance improvement in terms of bit-error rate when compared with the case of random parameters selection. These results corroborate the benefits of our adaptive parameters approach.
Dynamics of Mechanisms with Superior Couplings
Authors: Ungureanu Liviu Marian , Petrescu Florian Ion Tiberiu
Published: September 2021

The paper briefly presents the dynamic synthesis of mechanisms with superior couplings, force, and speed distribution, efficiency, loss coefficient, dynamic coefficient or motion transmission function, determination of variable angular input speed from the crank or cam based on solving the equation Lagrange, the determination of the dynamic variation of the follower (adept) based on the integration of Newton’s equation, and the dynamic analysis of several models taken into account. In the end, the original relations for calculating the efficiency of a gear are presented.
Design and Motion Simulation of an Underwater Glider in the Vertical Plane
Authors: Huang Jiafeng , Choi Hyeung-Sik , Jung Dong-Wook , Lee Ji-Hyeong , Kim Myung-Jun , Choo Ki-Beom , Cho Hyun-Joon , Jin Han-Sol
Published: September 2021

Net buoyancy, as the main power source for the motion of an underwater glider, is affected by the pump or bladder that the glider adopts to change its buoyancy force in water. In this study, a new underwater glider that can dive to a depth of 400 m at a cruising speed of 2 knots, which is faster than conventional underwater gliders and is less affected by sea currents, is investigated. The UG resisting 400 m pressure on the buoyancy engine and achieving 2 knots’ speed was designed and constructed. For this UG, its steady-state attitude was studied according to the variance of the buoyancy center and the center of gravity with the buoyancy engine influenced by the displacement of the movable mass block. In motion simulation of the UG, the attitude of the UG under different displacement conditions was simulated in Simulink according to the displacements of the piston and the movable mass block. To validate the simulation performance, a UG was constructed and experiments were conducted. The simulation and experimental results were compared to show the reliability of the simulation results under limited conditions.
Development of Narrow Loop Joint for Precast Concrete Slabs with Fiber-Reinforced Mortar: Experimental Investigation of Material Properties and Flexural Behavior of Joint
Authors: Fujikura Shuichi , Nguyen Minh Hai , Baba Shotaro , Fujiwara Hiromi , Tategami Hisao , Murai Hiroyasu
Published: September 2021

In the replacement of the reinforced concrete slab in existing steel girder bridges, a loop joint is commonly used to join precast concrete slabs on site. However, a relatively wide joint is needed, and considerable time and effort are consumed to construct the joint due to the addition of transverse reinforcements to the joint on site. These disadvantages affect the progress of on-site construction and should be addressed, especially when this method is applied to highway bridges, where early traffic opening is necessary in many cases. This study proposes a narrow loop joint that has fiber-reinforced mortar without transverse reinforcements. Several material tests were conducted to determine a suitable material for the joint. A series of flexural loading tests of slabs was conducted to investigate the flexural behavior of the proposed loop joint with the selected material (polyvinyl alcohol (PVA) fibers). The results showed that the flexural capacity and deformation performance of the proposed joint with PVA fibers are equivalent to those of the conventional loop joint.
Effect of Plasma Surface Modification on Print Quality of Biodegradable PLA Films
Authors: Izdebska-Podsiadły Joanna
Published: September 2021

PLA films, as non-absorbent materials, require modification of the surface before the printing process in order to improve the wettability of the substrate and to obtain proper ink adhesion to the substrate. In this paper, the surfaces of two kinds of PLA films were modified using plasma activation with parameters enabling high surface free energy (SFE) values, and then the films were printed on using different kinds of flexographic inks. Two gases, oxygen and argon, were used for activation, as these make it possible to obtain good hydrophilicity and high SFE values while having different effects on the roughness, or the degree of surface etching. Plasma-activated films were subsequently subjected to the measurements of: contact angle with water, diiodomethane and three printing inks, roughness, weight change, strength properties, color and gloss change, and SFE was determined. Unmodified and activated films were flexographically printed in laboratory conditions and then the quality of obtained prints was analyzed. The results showed a strong effect of activation with both oxygen and argon plasma on the SFE value of the films and the contact angles of water and inks, with the gas used for plasma activation and the type of film significantly influencing the thickness of the fused ink layer and the resultant color. Moreover, plasma activation had a especially favorable and significant effect on the quality of prints made with water-based inks, while it had little effect when printing with solvent-based inks.
Influence of Pre-Etched Area and Functional Monomers on the Enamel Bond Strength of Orthodontic Adhesive Pastes
Authors: Tezuka Yuriko , Namura Yasuhiro , Utsu Akihisa , Wake Kiyotaka , Uchida Yasuki , Inaba Mizuki , Takamizawa Toshiki , Motoyoshi Mitsuru
Published: September 2021

This study was performed to investigate the influence of pre-etching area and functional monomers in orthodontic adhesive pastes on enamel bond strength. Bovine enamel was partially pre-etched with phosphoric acid for 30 s over areas with a diameter of 1.0, 2.0 or 3.0 mm, and metal brackets were then bonded with or without functional monomers in the orthodontic adhesive paste. For the baseline groups, the whole adherent area was pre-etched. The shear bond strength (SBS) and adhesive remnant index (ARI) were determined. The adhesive paste/enamel interfaces were observed by scanning electron microscopy (SEM). Although the adhesive paste with functional monomers showed higher SBS than the functional monomer-free adhesive paste in all groups, there were no significant differences in SBS between them regardless of the pre-etched area. The SBS increased with increasing pre-etched area in both orthodontic adhesive pastes. In SEM images of adhesive paste/enamel interfaces, although adhesive with functional monomers showed excellent adaptation, the functional monomer-free adhesive paste showed gap formation at the interface. These findings suggested that the pre-etching area greatly influenced bond strength, regardless of the presence or absence of the functional monomer in the orthodontic adhesive paste.
Insight into the Role of Cerium (III) Addition to a MgAl-LDH Coating on AA6082
Authors: Fedel Michele , Zampiccoli Michele
Published: September 2021

In this work, Ce doped MgAl-LDHs layers have been developed through an in-situ synthesis method on 6082 aluminum surface. The aim was to gain mechanistic insight into the role of Ce(III) as an active corrosion inhibitor embedded in the LDHs layer. The development of the LDH structure was verified by checking the presence of the characteristic XRD peaks, the platelet morphology (evaluated by SEM-EDXS) and the functional groups (by FTIR-ATR analyses). The same techniques were employed to assess the effect of a prolonged immersion time in 0.1 NaCl on the Ce doped MgAl-LDH coatings. Electrochemical impedance spectroscopy (EIS) was employed to monitor the evolution of the electrochemical properties of the coatings during prolonged immersion in saline solutions. The findings suggest a crystallization/dissolution/precipitation mechanism which implies: (i) the formation of crystalline cerium compounds, such as Ce(OH)3, in the LDH structure during the synthesis; (ii) the dissolution upon exposure to the NaCl solution, thus leading to cerium ions release; (iii) the precipitation of amorphous Ce oxides/hydroxides at the cathodic sites when the metal starts to corrode; (iv), the consequent mitigation of the electrochemical activity of the metal and, thus, the reduction of the extent of corrosion.
Effects of a Dual-Purpose Inoculant on the Quality and Aerobic Stability of Corn Silage at the Laboratory and Field Scales
Authors: Weng Hsiu-Ming , Kao Li-Chen , Wang Shu-Min , Chen Chia-Sheng , Lee Ting-Yu , Chang Hsiao-Tung , Young San-Land , Lin Jin-Seng
Published: September 2021

This study investigated the effects of a dual-purpose inoculant (DPI) on the fermentation profile, nutritive value, and aerobic stability of silage. The inoculant effect was first examined with minisilos, and the results were later validated with 400-kg silo bales and a 40-t bunker silo. Briefly, whole-plant corn harvested at the one-half to two-thirds milk line stage was chopped and then treated with or without inoculant containing Lactobacillus plantarum LP1028 and Lactobacillus buchneri LBC1029 at application rates of 2.5 × 105 cfu and 5.0 × 105 cfu per gram of fresh forage, respectively. The results showed that applying DPI had no effect on the nutritive value in all trials. DPI inoculation also slowed yeast and mold growth in silage under aerobic exposure. Inoculation may double the aerobic stability time after 105 d of ensiling (53.25 vs. 113.20 h) in a bunker silo. This study successfully examined the effectiveness of DPI in minisilos, and the results were consistent when moving from the laboratory to the field. Applying DPI made the fermentation more heterolactic without compromising the silage nutritive value, and increasing acetic acid acted as an antifungal agent to inhibit spoilage microbial growth and improve silage aerobic stability.
Fast Stepwise Inertial Control Scheme of a DFIG for Reducing Second Frequency Drop
Authors: Xu Yien , Yang Dejian , Huang Jiejie , Zhang Xinsong , Hua Liang
Published: September 2021

With the fast growth in the penetration of wind power, doubly fed induction generators (DFIGs) are recommended for their ability to enforce grid codes that provide inertial control services by releasing rotational energy. However, after supporting the system frequency, a second frequency drop (SFD) is prone to occurring to regain the rotor speed caused by the sudden reduction in output. In this article, we propose a torque limit-based fast stepwise inertial control scheme of a DFIG using a piecewise reference function for reducing the SFD while preserving the frequency nadir (FN) with less rotor energy released. To achieve the first objective, the power reference increases to the torque limit and then decays with the rotor speed toward the preset operating point. To achieve the second objective, the power reference smoothly lessens over time based on the exponential function. The performance of the proposed stepwise inertial control strategy was studied under various scenarios, including constant wind speed and ramp down wind speed conditions. The test results demonstrated that the frequency stability is preserved during the frequency support phase, while the second frequency drop and mechanical stress on the wind turbine reduce during the rotor speed restoration phase when the DFIG implements the proposed stepwise inertial control scheme.
Definition of a Protocol to Manage and Officially Confirm SHB Presence in Sentinel Honeybee Colonies
Authors: Formato Giovanni , Federico Giovanni , Di Ruggiero Camilla , Pietropaoli Marco , Milito Marcella , Mutinelli Franco
Published: September 2021

Given the consolidated circulation of Aethina tumida (SHB) in Reggio Calabria and Vibo Valentia provinces of Calabria region (Southern Italy), the need for a more effective and less time-consuming approach to SHB surveillance emerged. Accordingly, honeybee sentinel colonies were established in the infested areas under the supervision and management of the Veterinary Services of the Local Health Unit. In this short communication, we present the protocol adopted in the Calabria region to manage the SHB positive sentinel honeybee colonies. The procedures for safely packing and transport the SHB infested sentinel honeybee colonies from the field to the official laboratory and the subsequent procedure for their careful inspection in the laboratory are illustrated.
Effect of Urea Addition on Anatase Phase Enrichment and Nitrogen Doping of TiO2 for Photocatalytic Abatement of Methylene Blue
Authors: Asif Maira , Zafar Muhammad , Akhter Parveen , Hussain Murid , Umer Adeel , Razzaq Abdul , Kim Woo-Young
Published: September 2021

TiO2-based materials are commonly employed as photocatalysts for industrial wastewater treatment. The primary reasons of employing TiO2 include cost effectiveness, ready availability, eco-friendliness, non-toxic behavior, and exceptional resistance towards photo-corrosion. However, the wider band gap of pure TiO2 restricts its performance because of its optical absorption of solar light to the ultraviolet (UV) region only, and to some extent of photo-excited charge recombination. In the present work an attempt is made to develop a facile synthesis approach by using urea, a cheap chemical precursor, to form nitrogen doped TiO2 with the key objective of extended light absorption and thus enhanced photocatalytic performance. It was also observed that the urea-induced anatase phase enrichment of TiO2 is another key factor in promoting the photocatalytic performance. The photocatalysts prepared by varying the amount of urea as a nitrogen dopant precursor, are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and photoluminescence (PL) to evaluate their crystallinity, morphology, functional groups, and charge separation properties, respectively. Moreover, the surface area was also estimated by physicochemical adsorption. The maximum nitrogen-doped sample yielded >99% photodegradation efficiency of methylene blue (MB) dye-simulated wastewater as compared to a pure TiO2 sample which exhibited 6.46% efficiency. The results show that the simultaneous factors of nitrogen doping and anatase phase enhancement contributes significantly towards the improvement of photocatalytic performance.
Can ISO GPS and ASME Tolerancing Systems Define the Same Functional Requirements?
Authors: Humienny Zbigniew
Published: September 2021

Geometrical tolerances are defined in the ISO Geometrical Product Specification system that is used worldwide, but on the other hand, the ASME Y14.5 standard is used in American companies to define how far actual parts may be away from their nominal geometry. This paper aimed to investigate whether specifications defining acceptable geometrical deviations in one system can be transformed to specifications in the other system. Twelve selected cases are discussed in the paper. Particularly, two cases of size tolerance, three cases of form tolerances, one case of orientation tolerance, four cases of position tolerance (including position tolerance with MMR for the pattern of five holes) and, finally, two cases of surface profile tolerance (unequally disposed tolerance zone and dynamic profile tolerance). The issue is not only in the several different symbols and a set of different defaults, but also in the different meanings and different application contexts of some symbols that have the same graphical form. The answer to the question raised in the paper title is yes for the majority of indications specified according to ASME Y14.5 when new tools from the 2017 edition of ISO 1101 are applied.
An Evaluation of the Demineralizing Effects of Various Acidic Solutions
Authors: Kolumban Agnes , Moldovan Marioara , Țig Ioan Andrei , Chifor Ioana , Cuc Stanca , Bud Marius , Badea Mindra Eugenia
Published: September 2021

The purpose of this study was to evaluate which of the techniques and acids included in this in vitro research can induce artificial caries lesions in the most natural way. White spot lesions were created using six different demineralizing solutions in liquid form (lactic acid; orthophosphoric acid; formic acid; and an acid solution that contains calcium chloride, sodium phosphate and acetic acid) and gel form (hydrochloric acid and orthophosphoric acid). Radiographs, photographs and readings with a DIAGNODent™ pen, VITA Easyshade and a scanning electron microscope (SEM) were made in the initial situation, after 30 min, 1 h, 24 h and 96 h of demineralization. The total color change (ΔE) values in most cases presented statistically significant differences. SEM images showed different aspects of the enamel surface for each type of acid. Only in the case of exposed dentine did the DIAGNODent™ pen record significant differences. There was no noticeable radio-translucency of the teeth treated for a short period of time, but after 24 h, the absence of enamel and major demineralization of dentine were visible. Acids in the liquid state can penetrate and demineralize dental structures deeper than those that are more viscous. This study should be repeated with a protocol that includes remineralization. Using weaker acids would be another direction that could lead to more interesting findings.
Effects of Glutathione Diminishment on the Immune Responses against Mycobacterium tuberculosis Infection
Authors: Cao Ruoqiong , Kolloli Afsal , Kumar Ranjeet , Owens James , Sasaninia Kayvan , Vaughn Charles , Singh Mohkam , Truong Edward , Kachour Nala , Beever Abrianna , Khamas Wael , Subbian Selvakumar , Venketaraman Vishwanath
Published: September 2021

Mycobacterium tuberculosis (M. tb), the causative agent of tuberculosis (TB), continues to be a global health burden. We have reported that patients with marked deficiency in the production of glutathione (GSH) had impaired granulomatous effector responses against M. tb infection, which were restored when supplementing patients with liposomal GSH (lGSH). However, the effects of GSH deficiency in the lung parenchyma in altering granuloma formation and effector responses against M. tb infection remain unexplored. We aim to elucidate the effects of diethyl maleate (DEM)-induced GSH deficiency during an active M. tb infection in an in vivo mouse model. We assessed for total and reduced GSH levels, malondialdehyde (MDA) levels, cytokine profiles, granuloma formation and M. tb burden. DEM administration significantly diminished total and reduced GSH levels in the lungs and plasma and increased MDA levels in infected mice compared to sham-treated controls. DEM treatment was also associated with an increase in IL-6, TNF-α and ill-formed granulomas in infected mice. Furthermore, M. tb survival was significantly increased along with a higher pulmonary and extrapulmonary bacterial load following DEM treatment. Overall, GSH deficiency led to increased oxidative stress, impaired granuloma response, and increased M. tb survival in infected mice. These findings can provide insight into how GSH deficiency can interfere with the control of M. tb infection and avenues for novel therapeutic approaches.
Design of ZnO-Drug Nanocarriers against the Main Protease of SARS-CoV-2 (COVID-19): An In Silico Assay
Authors: Díaz-Cervantes Erik , Zenteno-Zúñiga Cristal , Rodríguez-González Vicente , Aguilera-Granja Faustino
Published: September 2021

The treatment of coronavirus diseases (COVID-19) is a principal aim worldwide that is required restore public health in the population. To this end, we have been studied several kinds of de novo and repurposed drugs to investigate their ability to inhibit the replication of the virus which causes the current pandemic—the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, finding a vehicle that promotes the controlled dosage is vital for avoiding secondary effects. For this reason, the present work exposes a nanostructured carrier based on ZnO, which is coupled to three repurposed drugs (Chloroquine, Dipyridamole, and Lopinavir) to understand the chemical interaction of the formed composite. The designed composites are modeled and optimized using the DFT formalism. In obtaining exergonic adsorption energies, we found values between 0.582 to 2.084 eV, depending on the used drug. At the same time, the HOMO orbitals demonstrate the electronic overlap between the ZnO-Np and the Lopinavir, which is the molecule with the higher adsorption energy. Finally, we carried out a docking assay to investigate the interaction of free drugs and composites with the main protease of the SARS-CoV-2, finding that the coupling energy of the composites (at around to 0.03 eV) was higher, compared with the free drugs. As such, our results suggest a controlled dosage of the drug on the SARS-CoV-2 target.