bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical Characteristics and Healthcare Resource Utilization among Patients with Obstructive Hypertrophic Cardiomyopathy Treated in a Range of Settings in the United States
Authors: Butzner Michael , Rowin Ethan , Yakubu Amin , Seale Josiah , Robertson Laura A. , Sarocco Phil , Maron Martin S.
Published: July 2022

Obstructive hypertrophic cardiomyopathy (oHCM) has been studied primarily in comprehensive centers of excellence. Broadening the understanding of patients with oHCM in the general population may improve identification and treatment in other settings. This retrospective cohort study identified adults with oHCM from a large electronic medical record database comprising data from 39 integrated delivery networks (IBM Explorys; observational period: January 2009–July 2019). Clinical characteristics, healthcare resource utilization (HCRU), and outcomes were reported. Of 8791 patients, 53.0% were female and the mean index age was 61.8 years. Cardiovascular drugs prescribed included beta-blockers (80.5%), calcium channel blockers (46.0%), and disopyramide (2.4%). Over time, heart failure, atrial fibrillation, and ventricular arrhythmias increased. Surgical procedures included septal myectomy (22.0%), alcohol septal ablation (0.6%), and heart transplantation (0.3%). Implantable cardioverter defibrillators were present in 11.2% of patients. After initial septal reduction therapy (SRT), HCRU increased and 550 patients (27.7%) required a reintervention. Of the overall group, 2.7% experienced sudden cardiac arrest by end of study. In conclusion, this cohort of patients with oHCM had guideline-recommended drug therapy and procedures. Despite this, heart failure, atrial fibrillation, and ventricular arrhythmias increased, and more than a quarter of patients undergoing SRT required reintervention. These unresolved issues emphasize the unmet need for new, effective therapies for patients with oHCM.
Safety and Effectiveness of Intravenous Iron Therapy in Patients Supported by Durable Left Ventricular Assist Devices
Authors: Peters Carli J. , Hanff Thomas C. , Genuardi Michael V. , Zhang Robert , Domenico Christopher , Atluri Pavan , Mazurek Jeremy A. , Urgo Kim , Wald Joyce , Tanna Monique S. , Shore Supriya , Acker Michael A. , Goldberg Lee R. , Margulies Kenneth B. , Birati Edo Y.
Published: July 2022

Aims: While it is common practice to use intravenous (IV) iron in patients with left ventricular assist devices (LVADs) and iron deficiency, there is insufficient evidence regarding outcomes in this patient population. We evaluated the safety and effectiveness of IV iron therapy in patients supported by LVADs with iron deficiency. Methods: We performed a retrospective analysis of iron deficient patients on continuous LVAD support at a large academic center between 2008 and 2019. Patients were divided into two cohorts based on IV iron sucrose treatment. The primary endpoint was hemoglobin at 12 weeks. Secondary endpoints were mean corpuscular volume (MCV) and New York Heart Association (NYHA) class at 12 weeks. Safety endpoints included hospitalization, infection, pump thrombosis, arrhythmia, and gastrointestinal bleed. Models were weighted by the inverse probability of receiving IV iron using a propensity score, and endpoints were adjusted for their corresponding baseline values. Results: Among 213 patients, 70 patients received IV iron and 143 patients did not. Hemoglobin at 12 weeks was significantly greater among those treated (intergroup difference: 0.6 g/dL; 95% CI, 0.1 to 1.1; p = 0.01), while MCV was similar in both groups (intergroup difference: 0.7 μm3; 95% CI, −1.3 to 2.7; p = 0.50). NYHA class distribution at 12 weeks was significantly different (odds ratio for improvement: 2.84; 95% CI, 1.42 to 4.68; p = 0.003). The hazards of adverse events in each group were similar. Conclusions: In patients with LVADs and iron deficiency, treatment with IV iron sucrose was safe and associated with improvements in functional status and hemoglobin.
Therapeutic Efficacy and Safety of Osteoinductive Factors and Cellular Therapies for Long Bone Fractures and Non-Unions: A Meta-Analysis and Systematic Review
Authors: Kaspiris Angelos , Hadjimichael Argyris C. , Vasiliadis Elias S. , Papachristou Dionysios J. , Giannoudis Peter V. , Panagiotopoulos Elias C.
Published: July 2022

Background: Long bone fractures display significant non-union rates, but the exact biological mechanisms implicated in this devastating complication remain unclear. The combination of osteogenetic and angiogenetic factors at the fracture site is an essential prerequisite for successful bone regeneration. The aim of this study is to investigate the results of the clinical implantation of growth factors for intraoperative enhancement of osteogenesis for the treatment of long bone fractures and non-unions. Methods: A systematic literature review search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in the PubMed and Web of Science databases from the date of inception of each database through to 10 January 2022. Specific inclusion and exclusion criteria were applied in order to identify relevant studies reporting on the treatment of upper and lower limb long bone non-unions treated with osteoinductive or cellular factors. Results: Overall, 18 studies met the inclusion criteria and examined the effectiveness of the application of Bone Morphogenetic Proteins-2 and -7 (BMPs), platelet rich plasma (PRP) and mesenchymal stem cells (MSCs). Despite the existence of limitations in the studies analysed (containing mixed groups of open and close fractures, different types of fractures, variability of treatment protocols, different selection criteria and follow-up periods amongst others), their overall effectiveness was found significantly increased in patients who received them compared with the controls (I2 = 60%, 95% CI = 1.59 [0.99–2.54], Z =1.93, p = 0.05). Conclusion: Administration of BMP-2 and -7, PRP and MSCs were considered effective and safe methods in fracture treatment, increasing bone consolidation, reducing time to repair and being linked to satisfactory postoperative functional scores.
Titanium Dioxide/Polysiloxane Composites: Preparation, Characterization and Study of Their Color Stability Using Thermochromic Pigments
Authors: Papachristou Evangelia , Korres Dimitrios , Mamma Diomi , Kekos Dimitris , Tarantili Petroula A. , Polyzois Gregory
Published: July 2022

In order to improve thermomechanical, antibacterial and temperature-controlled color-response performance of polydimethylsiloxane (PDMS) in maxillofacial prostheses, the incorporation of titania (TiO2) nanoparticles and thermochromic pigments (TCP) into PDMS was examined. The thermal transitions of TiO2/PDMS nanocomposites, investigated by differential scanning calorimetry (DSC), remain almost unaffected, while an increase of the crystallinity of PDMS was recorded in specimens with higher titania concentrations. The incorporation of titania improves the thermal stability, as it was revealed by thermogravimetric analysis (TGA), as well as the tensile properties of the reinforced elastomer. Nanocomposites with 10 wt% titania presented antibacterial activity against Escherichia Coli, leading to 72% reduction of the bacterial colony after 3 h of exposure. Specimens colored with red TCP (0.2 and 0.6 wt%) showed significant color change at a lower temperature (−20 °C) in comparison with that at an ambient temperature, especially at lower TCP concentration (0.2 wt%). Accelerating aging experiments, consisting of repeated cycles of combined exposure to UV-radiation and damp heating, of PDMS colored with TCP showed poor color stability of the specimens, from the first hours of exposure. The addition of titania to polysiloxane specimens works as an opacifier providing a positive effect on the color stability of the examined thermochromic pigment.
Advances in Understanding the Pathogenesis of Craniofacial Birth Defects
Authors: Tavares Andre L. P. , Moody Sally A.
Published: July 2022

Each year approximately 35% of babies are born with craniofacial abnormalities of the skull, jaws, ears, and/or teeth, which in turn can lead to problems in feeding, hearing, and sight [...]
Nitric Oxide Metabolism Affects Germination in Botrytis cinerea and Is Connected to Nitrate Assimilation
Authors: Anta-Fernández Francisco , Santander-Gordón Daniela , Becerra Sioly , Santamaría Rodrigo , Díaz-Mínguez José María , Benito Ernesto Pérez
Published: July 2022

Nitric oxide regulates numerous physiological processes in species from all taxonomic groups. Here, its role in the early developmental stages of the fungal necrotroph Botrytis cinerea was investigated. Pharmacological analysis demonstrated that NO modulated germination, germ tube elongation and nuclear division rate. Experimental evidence indicates that exogenous NO exerts an immediate but transitory negative effect, slowing down germination-associated processes, and that this effect is largely dependent on the flavohemoglobin BCFHG1. The fungus exhibited a “biphasic response” to NO, being more sensitive to low and high concentrations than to intermediate levels of the NO donor. Global gene expression analysis in the wild-type and ΔBcfhg1 strains indicated a situation of strong nitrosative and oxidative stress determined by exogenous NO, which was much more intense in the mutant strain, that the cells tried to alleviate by upregulating several defense mechanisms, including the simultaneous upregulation of the genes encoding the flavohemoglobin BCFHG1, a nitronate monooxygenase (NMO) and a cyanide hydratase. Genetic evidence suggests the coordinated expression of Bcfhg1 and the NMO coding gene, both adjacent and divergently arranged, in response to NO. Nitrate assimilation genes were upregulated upon exposure to NO, and BCFHG1 appeared to be the main enzymatic system involved in the generation of the signal triggering their induction. Comparative expression analysis also showed the influence of NO on other cellular processes, such as mitochondrial respiration or primary and secondary metabolism, whose response could have been mediated by NmrA-like domain proteins.
Genetic Characterization of Puccinia striiformis f. sp. tritici Populations from Different Wheat Cultivars Using Simple Sequence Repeats
Authors: Wang Shuhe , Gao Chaofan , Sun Qiuyu , Liu Qi , Wang Cuicui , Guo Fangfang , Ma Zhanhong
Published: July 2022

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important fungal diseases affecting wheat (Triticum aestivum L.) worldwide. In this study, the genetic diversity and population structure of Pst isolates were analyzed using 15 microsatellite markers. Isolates were collected from five wheat cultivars with different levels of resistance from Yanting county and Fucheng district, Mianyang city, Sichuan province, China. The aim of this study was to investigate whether Pst populations are differentiated by wheat genotype or geographic origin. Seventy-six multilocus genotypes (MLGs) were identified from all 289 single uredinial isolates. In general, the genotypic diversity of Pst populations from five wheat cultivars in Fucheng was higher than that in Yanting. In addition, the genetic diversity was highest in the Pst populations from Mianmai 367, a cultivar considered to be highly resistant. The unweighted pair group method with arithmetic mean (UPGMA) phylogenetic tree, Bayesian clustering analysis, and minimum spanning network for the MLGs revealed two major genetic clusters based on geographical location. Greater differentiation was observed between the populations from the two sampling locations than between the populations from different hosts in the same location. The results suggest that geographic and environmental differences could partially explain the genetic differentiation of Pst more than wheat genotype. This study provides novel insight into the interactions between Pst populations and their hosts. The results could be helpful in designing more effective management strategies for stripe rust in wheat production.
Malassezia: Zoonotic Implications, Parallels and Differences in Colonization and Disease in Humans and Animals
Authors: Hobi Stefan , Cafarchia Claudia , Romano Valentina , Barrs Vanessa R.
Published: July 2022

Malassezia spp. are commensals of the skin, oral/sinonasal cavity, lower respiratory and gastrointestinal tract. Eighteen species have been recovered from humans, other mammals and birds. They can also be isolated from diverse environments, suggesting an evolutionary trajectory of adaption from an ecological niche in plants and soil to the mucocutaneous ecosystem of warm-blooded vertebrates. In humans, dogs and cats, Malassezia-associated dermatological conditions share some commonalities. Otomycosis is common in companion animals but is rare in humans. Systemic infections, which are increasingly reported in humans, have yet to be recognized in animals. Malassezia species have also been identified as pathogenetic contributors to some chronic human diseases. While Malassezia species are host-adapted, some species are zoophilic and can cause fungemia, with outbreaks in neonatal intensive care wards associated with temporary colonization of healthcare worker’s hands from contact with their pets. Although standardization is lacking, susceptibility testing is usually performed using a modified broth microdilution method. Antifungal susceptibility can vary depending on Malassezia species, body location, infection type, disease duration, presence of co-morbidities and immunosuppression. Antifungal resistance mechanisms include biofilm formation, mutations or overexpression of ERG11, overexpression of efflux pumps and gene rearrangements or overexpression in chromosome 4.
In Vitro Antifungal Susceptibility Profile of Miltefosine against a Collection of Azole and Echinocandins Resistant Fusarium Strains
Authors: Nosratabadi Mohsen , Akhtari Javad , Faeli Leila , Haghani Iman , Aghili Seyed Reza , Shokohi Tahereh , Hedayati Mohammad Taghi , Zarrinfar Hossein , Mohammadi Rasoul , Najafzadeh Mohammad Javad , Khodavaisy Sadegh , Al-Harrasi Ahmed , Javan-Nikkhah Mohammad , Kachuei Reza , Salimi Maryam , Fattahi Mahsa , Badali Hamid , Al Hatmi Abdullah M. S. , Abastabar Mahdi
Published: July 2022

Fusarium species are filamentous fungi that cause a variety of infections in humans. Because they are commonly resistant to many antifungal drugs currently available in clinical settings, research into alternative targets in fungal cells and therapeutic approaches is required. The antifungal activity of miltefosine and four comparators, amphotericin B, voriconazole, itraconazole, and caspofungin, were tested in vitro against a collection of susceptible and resistant clinical (n = 68) and environmental (n = 42) Fusarium isolates. Amphotericin B (0.8 μg/mL) had the lowest geometric mean (GM) MICs/MECs values followed by miltefosine (1.44 μg/mL), voriconazole (2.15 μg/mL), caspofungin (7.23 μg/mL), and itraconazole (14.19 μg/mL). Miltefosine was the most effective agent against Fusarium isolates after amphotericin B indicating that miltefosine has the potential to be studied as a novel treatment for Fusarium infections.
Effects of Mixed Adding Crude Extracts of β-Glucosidases from Three Different Non-Saccharomyces Yeast Strains on the Quality of Cabernet Sauvignon Wines
Authors: Liao Jing , Zhang Shuangmei , Zhang Xiuyan
Published: July 2022

The aim of this study was to investigate the effects of crude extracts of β-glucosidase from Issatchenkia terricola SLY-4, Pichia kudriavzevii F2-24 and Metschnikowia pulcherrima HX-13 (termed as SLY-4E, F2-24E and HX-13E) on the flavor complexity and typicality of Cabernet Sauvignon wines. The grape must was fermented using Saccharomyces cerevisiae with single or mixed SLY-4E, F2-24E and HX-13E. The physicochemical characteristics, volatile aroma compounds, total anthocyanins and sensory attributes of the wines were determined. Adding SLY-4E, F2-24E and HX-13E in wines resulted in a decrease in the anthocyanin content, total acids and volatile acids in wines but an increase in the content of terpenes, benzene derivatives, higher alcohols and esters, which may enhance wine sensory qualities and result in loss of wine color. Different adding strategies of β-glucosidase led to a variety of effects on wine aroma. S/H/F-Ew significantly increased the content of benzene derivatives, higher alcohols and long-chain fatty acid esters, which enhanced the fruity and floral flavor of wines. F2-24E significantly increased the content of short- and medium-chain fatty acid esters, acetate esters and carbonyl compounds. The results indicated that the mixed addition of non-Saccharomyces crude extracts and co-fermentation with S. cerevisiae could further improve wine flavor quality.
Lack of Difference in Tocilizumab Efficacy in the Treatment of Severe COVID-19 Caused by Different SARS-CoV-2 Variants
Authors: Oliynyk Oleksandr , Barg Wojciech , Oliynyk Yanina , Dubrov Serhij , Gurianov Vitaliy , Rorat Marta
Published: July 2022

Tocilizumab (TOC) is presumed to be an effective and safe treatment for severe COVID-19, but its usefulness has not been yet investigated for different SARS-CoV-2 variants. This study aimed to evaluate the influence of TOC on mortality in patients with severe COVID-19 caused by Delta and non-Delta SARS-CoV-2 variants. In a retrospective analysis, we compared the medical records of 78 and 224 patients with severe COVID-19 due to Delta and non-Delta variants, respectively. A total of 30 patients with Delta and 84 with non-Delta variants were treated with TOC in addition to standard therapy. There were no statistically significant differences in mortality rate when comparing Delta vs. non-Delta patients nor when comparing those treated with TOC vs. not treated with TOC in both variants. Using a logistic regression model, in the examined population as a whole, we found an increased (p < 0.05) risk of death as leukocyte and erythrocyte counts decreased and as procalcitonin increased. Increased procalcitonin was significant for mortality in the Delta group, while decreased IL-6, leukocytes, and platelets and increased fibrinogen and procalcitonin were significant in the non-Delta group. Tocilizumab efficacy in severe COVID-19 does not differ between Delta or non-Delta virus variants. The Delta variant of SARS-CoV-2 does not increase mortality when compared to other virus strains.
Land Use Optimization for Coastal Urban Agglomerations Based on Economic and Ecological Gravitational Linkages and Accessibility
Authors: Pan Tingting , Yan Fengqin , Su Fenzhen , Lyne Vincent , Zhou Chaodong
Published: July 2022

Urban agglomerations (UA) are attracting increasing research attention as a global emergent phenomenon, whereby regional collaborative linkages between cities attracts and agglomerates development. However, these studies also acknowledge that ecological values may be negatively impacted by re-development, ecological fragmentation, and proximity or downstream impacts. Sustainable development, therefore, requires balancing forces from economic attraction and ecological repulsion. Forces similar to economic ones may also operate in attracting ecological enhancement towards higher-valued ecological regions; however, research regarding the role of the self-collaborative gravity-like forces shaping UA is limited in land use optimization. To assist planners, this study developed a new multi-objective land use optimization of UA that explored the intensity of economic ties and ecological gradients using the multi-objective NSGA-II algorithm. In this model, economic linkage intensity (ELI) and accessibility were used to calculate a modified GDP (gross domestic product), while the NDVI (normalized difference vegetation index) was used for the modified ESV (ecosystem services value). Spatial allocation with implicit economic accessibility relationships was enhanced through a two-step mutation operator, including a “gravity flip” spatial orientation factor. Compared to the standard NSGA-II algorithm, models of future land use of the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) in 2030 have shown that the modified GDP value in our model increased by 7.41%, while the conversion rate of high-density vegetation reduced by 7.92%. The results highlighted the importance of linkage and accessibility factors in enhancing the clustering of cities. In tandem, the modified ESV also enhances ecosystem services contributions of higher value vegetated land through decentralized built-up developments. The proposed model provides managers with a comprehensive and efficient land use solution model that accounts for intrinsic linkage factors shaping the development of compact urban agglomerations.
A Quantitative Survey of Effect of Semi-Natural Habitat Composition and Configuration on Landscape Heterogeneity in Arable Land System
Authors: Guo Xiaoyu , Guan Minghao , Bian Zhenxing , Wang Qiubing
Published: July 2022

Arable land systems are complex ecosystems composed of cultivated land and semi-natural habitats. Retaining an appropriate proportion of semi-natural habitats in arable land systems is beneficial for enhancing landscape heterogeneity and biodiversity. However, it is unclear how many semi-natural habitats need to be retained in arable land systems to improve landscape heterogeneity. In this study, the land use data of four counties were used as the data source in the Lower Liaohe Plain, Liaoning Province, and Rao’s quadratic entropy index (Q) was used to quantitatively characterize the landscape heterogeneity. We aimed to explore the minimum proportion of semi-natural habitat required to maintain high landscape heterogeneity and determine the independent and interactive effects of semi-natural habitat composition and configuration on landscape heterogeneity. We found that (1) maintaining a 5% proportion of semi-natural habitats is the minimum threshold for achieving high landscape heterogeneity in arable land systems. Retaining a 10% share of semi-natural habitats is beneficial for both agricultural production and land ecology. (2) The combination of woodland, water and ditches was good for improving landscape heterogeneity. Connectivity in semi-natural habitats is critical to improving landscape heterogeneity. (3) The interaction of semi-natural habitat composition and configuration had a strong effect on landscape heterogeneity (53.1%). Semi-natural habitat configuration was found to be more important than composition for landscape heterogeneity. The role of semi-natural habitat composition and configuration in maintaining landscape heterogeneity and supporting the sustainability of land use therefore needs to be considered in arable land systems.
Correction: Marazziti et al. The Microbiota/Microbiome and the Gut–Brain Axis: How Much Do They Matter in Psychiatry? Life 2021, 11, 760
Authors: Marazziti Donatella , Buccianelli Beatrice , Palermo Stefania , Parra Elisabetta , Arone Alessandro , Beatino Maria Francesca , Massa Lucia , Carpita Barbara , Barberi Filippo M. , Mucci Federico , Dell’Osso Liliana
Published: July 2022

The authors of this paper [...]
Acetaminophen Hepatotoxicity: Not as Simple as One Might Think! Introductory Comments on the Special Issue—Recent Advances in Acetaminophen Hepatotoxicity
Authors: Jaeschke Hartmut
Published: July 2022

Acetaminophen (N-acetyl-para-aminophenol (APAP)) is one of the most-studied drugs worldwide [...]
Effects of Fly Ash Inclusion and Alkali Activation on Physical, Mechanical, and Chemical Properties of Clay
Authors: Turan Canan , Javadi Akbar A. , Vinai Raffaele , Russo Giacomo
Published: July 2022

This study investigated the improvement in the behaviour of a clay soil due to the addition of alkali-activated fly ash as a stabilising agent, and the effects of different activation factors such as alkali dosages and silica moduli. The alkali activator solution used was a mixture of sodium silicate and sodium hydroxide. Class F fly ash was used as the precursor material for the geopolymerisation process. Soil samples stabilised with non-activated class F fly ash were prepared and tested to compare the results with samples stabilised with alkali-activated fly ash. Compaction tests, unconfined compressive strength tests, X-ray diffraction analysis, and scanning electron microscopy analysis were carried out on samples cured 1, 7, and 28 days at room conditions. The results showed that the compressive strength of stabilised soil significantly increased when the fly ash was activated. The optimal activation parameters to stabilise the soil were found to be alkali dosages in the range of 12% to 16% and a silica modulus of 1.25. The highest compressive strength recorded was at 1293 kPa with an alkali dosage of 16% and a silica modulus of 1.25, while for the non-stabilised soil, it was at 204 kPa at 28 days of curing. Mineralogical analysis showed a decrease in the peak intensities of kaolinite and illite, while microstructural analysis indicated an alteration in soil texture with the addition of the alkali-activated fly ash.
PPM EMAT for Defect Detection in 90-Degree Pipe Bend
Authors: Wang Linhao , Xu Jiang , Chen Dong
Published: July 2022

Aircraft pipelines are mainly used for the storage and transportation of fuel, hydraulic oil and water, which are mostly bent pipes of non-ferromagnetic materials. We used PPM (Periodic Permanent Magnet) EMAT (Electromagnetic Acoustic Transducer) to detect the defects at 90-degree bends. A simulation model was established by finite element software to study the propagation characteristics and defect detection capability of T (0, 1) mode-guided wave in aluminum pipe bend. In terms of propagation characteristics, the energy of the guided wave was focused in the extrados of the bend, and the guided waves in the intrados and extrados of the bend were separated due to the difference in propagation distance. Regarding defect detection capability, T (0, 1) mode-guided wave had the highest detection sensitivity for the defect in the extrados of the bend and the lowest detection sensitivity for the defect in the middle area of the bend. We designed a PPM EMAT for 320 kHz to verify the simulation results experimentally, and the experimental results are in good agreement with the simulation results.
Hydroxyethyl Cellulose Promotes the Mucin Retention of Herbal Extracts Active against Streptococcus mutans
Authors: Livne Shiri , Simantov Sapir , Rahmanov Arkadi , Jeffet Uziel , Sterer Nir
Published: July 2022

Streptococcus mutans is considered a major cariogenic bacterium. Most anti-cariogenic dentifrices are limited by a short exposure time. The aim of the present study was to test the hypothesis that adding a mucoadhesive agent to the formulation may increase its bioavailability and efficacy. We tested the effect of adding hydroxyethyl cellulose (HEC) to an herbal extract solution containing lavender, echinacea, sage, and mastic gum, which have been previously shown to be effective against Streptococcus mutans. Mucin-coated wells were treated with four test solutions: saline, herbal extracts, herbal extracts with HEC, and chlorhexidine. The wells were incubated with Streptococcus mutans and studied for biofilm formation (Crystal violet assay), acid production (lactate assay), acid tolerance (ATPase assay), and exopolysaccharide (EPS) production using fluorescent microscopy. The results showed that the addition of HEC to the herbal extract solution caused a significant reduction in Streptococcus mutans biofilm formation, lactic acid production, and EPS quantity (p < 0.001). These results suggest that HEC may be a beneficial added excipient to herbal extracts in an anti-cariogenic formulation.
Estimating Low- and High-Cyclic Fatigue of Polyimide-CF-PTFE Composite through Variation of Mechanical Hysteresis Loops
Authors: Panin Sergey V. , Bogdanov Alexey A. , Eremin Alexander V. , Buslovich Dmitry G. , Alexenko Vladislav O.
Published: July 2022

The fatigue properties of neat polyimide and the “polyimide + 10 wt.% milled carbon fibers + 10 wt.% polytetrafluoroethylene” composite were investigated under various cyclic loading conditions. In contrast to most of the reported studies, constructing of hysteresis loops was performed through the strain assessment using the non-contact 2D Digital Image Correlation method. The accumulation of cyclic damage was analyzed by calculating parameters of mechanical hysteresis loops. They were: (i) the energy losses (hysteresis loop area), (ii) the dynamic modulus (proportional to the compliance/stiffness of the material) and (iii) the damping capacity (calculated through the dissipated and total mechanical energies). On average, the reduction in energy losses reached 10–18% at the onset of fracture, whereas the modulus variation did not exceed 2.5% of the nominal value. The energy losses decreased from 20 down to 18 J/m3 (10%) for the composite, whereas they reduced from 30 down to 25 J/m3 (17%) for neat PI in the low-cycle fatigue mode. For high-cycle fatigue, energy losses decreased from 10 to 9 J/m3 (10%) and from 17 to 14 J/m3 (18%) for neat PI and composite, respectively. For this reason, the changes of the energy losses due to hysteresis are of prospects for the characterization of both neat PI and the reinforced PI-based composites.
DMA Analysis of Plasma Modified PVC Films and the Nature of Initiated Surface Changes
Authors: Janík Róbert , Kohutiar Marcel , Dubec Andrej , Eckert Maroš , Moricová Katarína , Pajtášová Mariana , Ondrušová Darina , Krbata Michal
Published: July 2022

The application of DCSBD (Diffuse Coplanar Surface Barrier Discharge) plasma is referred to as the surface modification/activation of materials. The exposure of material surfaces to DCSBD plasma is initiated by changes in their chemical composition, surface wettability and roughness. The given study presents the mentioned plasma application in the context of the modification of the material viscoelastic properties, namely the PVC polymer film. The measurement of viscoelastic properties changes of PVC was primarily examined by a sensitive thermal method of dynamic-mechanical analysis. This analysis allows identifying changes in the glass transition temperature of PVC, before and after DCSBD plasma application, Tangens Delta, supported by glass transition temperatures of Elastic and Loss modulus. The results of the present study prove that DCSBD plasma applied on both sides to PVC surfaces causes changes in its viscoelastic properties. In addition, these changes are presented depending on the variability of the material position, with respect to the winding of the electrodes in the ceramic dielectric generating the DCSBD plasma during modification. The variability of the PVC position holds an important role, as it determines the proportion of filamentous and diffuse components of the plasma that will interact with the material surface during modification. The application of DCSBD plasma must, therefore, be considered a complex modification of the material, and as a result, non-surface changes must also be considered.
Calculation Model of Mechanical and Sealing Properties of NiTi Alloy Corrugated Gaskets under Shape Memory Effect and Hyperelastic Coupling: Two Sealing Properties
Authors: Zhu Lingxue , Liu Yang , Li Mingxuan , Lu Xiaofeng , Zhu Xiaolei
Published: July 2022

Bolted flange connections are commonly used in process industries. Their sealing performance is greatly affected by the gasket. In this paper, a NiTi alloy corrugated gasket was simulated to reveal its sealing performance, considering the gasket surface roughness, shape memory effect and superelastic effect. A fluid–structure coupling analysis method that takes the real surface morphology of the gasket contact zone was proposed, and a leakage rate prediction model was established. The results showed that NiTi shape memory effect could enhance the sealing reliability in service and lower the leakage rate. The leakage rate of the NiTi alloy corrugated gasket is positively correlated with the internal pressure of the medium and the roughness of the sealing surface. The prediction model of the NiTi alloy corrugated gasket leakage rate has good reliability with an average error of about 16.81% compared with the simulation.
A Novel Preparation of Special-Shaped Phosphors-in-Glass by Gel Casting with Isobam for High-Power WLEDs Lighting
Authors: Liu Hongmei , Tian Junjie , Sun Honghao , Xu Qian , Yu Jinyan , Yao Qing
Published: July 2022

Phosphors-in-glass (PiGs) regarded as a promising phosphor-converter for white light emitting diodes (WLEDs) is being researched widely. However, there are few reports on the effect of changing the shape of PiGs on the color rendering index (CRI) and heat dissipation of WLEDs. In this paper, gel casting with Isobam was first attempted in preparing special-shaped PiGs successfully. It exhibited that 76 wt.% was the optimum solid content based on the rheological properties of slurry and the shrinkage of green bodies. The sintering rate should be kept at a low speed and glass transition temperature (Tg) of glass powders must be higher than sublimation temperatures (Ts) of APS and Isobam. The CRI of PiGs was increased by about 27% after changing the shape of PiGs from cylinder to dome. Most importantly, operating temperature also reduced effectively the increase of the surface area of PiGs. Therefore, changing the shape of PiGs by gel casting with Isobam is a creative way for high-power WLEDs lighting.
Microstructure and Friction Properties of CoCrFeMnNiTix High-Entropy Alloy Coating by Laser Cladding
Authors: Liu Pengfei , Si Wudong , Zhang Dabin , Dai Sichao , Jiang Benchi , Shu Da , Wu Lulu , Zhang Chao , Zhang Meisong
Published: July 2022

To enhance the friction and wear properties of 40Cr steel’s surface, CoCrFeMnNi high-entropy alloy (HEA) coatings with various Ti contents were prepared using laser cladding. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were used to characterize the phase composition, microstructure, and chemical composition of the samples. The findings demonstrated that the CoCrFeMnNiTix HEA coatings formed a single FCC phase. Fe2Ti, Ni3Ti, and Co2Ti intermetallic compounds were discovered in the coatings when the molar ratio of Ti content was greater than 0.5. The EDS findings indicated that Cr and Co/Ni/Ti were primarily enriched in the dendrite and interdendrite, respectively. Ti addition can effectively enhance the coating’s mechanical properties. The hardness test findings showed that when the molar ratio of Ti was 0.75, the coating’s microhardness was 511 HV0.5, which was 1.9 times the hardness of the 40Cr (256 HV0.5) substrate and 1.46 times the hardness of the CrCrFeMnNi HEA coating (348 HV0.5). The friction and wear findings demonstrated that the addition of Ti can substantially reduce the coating’s friction coefficient and wear rate. The coating’s wear resistance was the best when the molar ratio of Ti was 0.75, the friction coefficient was 0.296, and the wear amount was 0.001 g. SEM and 3D morphology test results demonstrated that the coating’s wear mechanism changed from adhesive wear and abrasive wear to fatigue wear and abrasive wear with the increase in Ti content.
Efficient Model of the Interaction of Elastomeric Filler with an Open Shell and a Chrome-Plated Shaft in a Dry Friction Damper
Authors: Dutkiewicz Maciej , Velychkovych Andrii , Shatskyi Ivan , Shopa Vasyl
Published: July 2022

The results of a study of the contact interaction of an open shell and a chrome-plated shaft with elastomeric filler installed coaxially are presented. The considered contact system is a model of the original design of the shell damper of dry friction. The design feature is the following: the bearing link of the damper is a thin-walled cylindrical shell with a cut along the generatrix; the working body of the damper is elastomeric filler; a hollow chrome-plated shaft centers the damper elements and allows it to be used in technological processes with the presence of aggressive and abrasive-containing media. The mechanical-mathematical modeling of the behavior of the presented damper under the conditions of operational loads has been carried out. The idea of identifying the properties of a cut isotropic shell, which bends under the conditions of a nonaxisymmetric contact load, and a strongly orthotropic continuous shell is applied. As a result, dependences were obtained to determine the rigidity and the maximum allowable load of the damper. The effect of the coefficient of friction of the contact pairs elastomer-shell and elastomer-shaft on the damper performance properties has been studied. A technique for the quasi-static analysis of structural damping in non-mobile, non-conservative shell systems with deforming filler has been developed. The hysteresis loops of the damper under a nonmonotonic load are constructed, the dependence of the amount of dissipated energy on the cycle asymmetry coefficient is found. An analysis of the results obtained showed that the use of open shells in friction shock absorbers can significantly reduce their rigidity compared to solid shells and thereby reduce the resonant frequencies of the dynamic system. This circumstance makes such vibration isolators particularly attractive for use in superresonance vibrators as working modules of drilling shock absorbers and elastic hangers of sucker rods in oil and gas production.
Effect of Shear and Pure Bending Spans on the Behaviour of Steel Beams with Corrugated Webs
Authors: Sharaky Ibrahim A. , Alharthi Yasir M. , Elamary Ahmed S.
Published: July 2022

The shear span-to-effective depth ratio is known to modulate the shear behaviour of steel beams with corrugated webs (SBCWs). However, present design standards for SBCWs do not adequately address this issue. The impact of shear span-to-effective depth ratio and pure bending spans on the failure mechanism of SBCWs was investigated in this study. Under four-point bending, three beams with shear-span-to-effective-depth-ratios ranging from 1.65 to 2.5 were examined to investigate the relationship between shear and bending spans and failure mechanisms. ANSYS software was used to create finite element models for the tested SBCWs using the finite element technique. In addition, the experimental findings are compared to two codes, specifically DASt-Rishtlinie015 and EN 1993-1-5. Moreover, an analytical section comprised of the creation of a three-dimensional (3D) finite element model (FEM) was implemented. Finally, a parametric study using the verified FE model was conducted to assess the impact of shear and pure bending spans on the overall behaviour of SBCWs. As a result, the shear span and horizontal fold length of CWSBs are key components for determining the strength and failure modes of beams. Furthermore, the load capabilities and stiffness of CWSBs were more greatly affected by increasing the shear span than by increasing the pure bending one.
Synthesis and Characterization of Functionalized Chitosan Nanoparticles with Pyrimidine Derivative for Enhancing Ion Sorption and Application for Removal of Contaminants
Authors: Hamza Mohammed F. , Wei Yuezhou , Althumayri Khalid , Fouda Amr , Hamad Nora A.
Published: July 2022

Modified chitosan has been widely used for heavy metals removal during the last few decades. In this research, the study was focused on the effect of modified chitosan particles after grafting with heterocyclic constituent for enhancing the sorption of Cr(VI) ions. Chitosan was functionalized by 2-thioxodihydropyrimidine-4,6(1H,5H)-dione, in which the synthesized composite considered as a nanoscale size with average 5–7 nm. This explains the fast kinetics of sorption with large surface area. The prepared sorbent was characterized by Fourier-transform infrared (FTIR), elemental analysis (EA), Brunauer–Emmett–Teller (BET surface area) theory, thermogravimetric analysis (TGA), mass spectroscopy, and scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) analyses. The experimental part of this work involved the application of the synthesized sorbent for the removal of Cr(VI) ions from highly contaminated tannery effluents that are characterized by a high concentration toward chromate ions with other associated toxic elements, i.e., Pb(II) and Cd (II) ions, which underscore the importance of this treatment. Under the selected conditions (K2Cr2O7 salt, Co: 100 mg L−1 and pH: 4), the sorption diagram shows high Cr(VI) sorption and fast uptake kinetics. The sorption was enhanced by functionalization to 5.7 mmol Cr g−1 as well as fast uptake kinetics; 30 min is sufficient for total sorption compared with 1.97 mmol Cr g−1 and 60 min for the non-grafted sorbent. The Langmuir and Sips equations were fitted for the sorption isotherms, while the pseudo-first order rate equation (PFORE) was fitted for the uptake kinetics.
A Teleoperation Framework Based on Heterogeneous Matching for Hydraulic Manipulator
Authors: Zhou Shizhao , Shen Chong , Zhu Shiqiang , Li Wenwen , Nie Yong , Chen Zheng
Published: July 2022

In recent years, hydraulic manipulators have been more and more widely used in the field of industrial automation because of their high power-to-weight ratio. Compared with autonomous control, bilateral teleoperation is a more reliable way to operate hydraulic manipulators on harsh occasions. However, teleoperation application in the hydraulic field is still limited due to operation accuracy and master–slave heterogeneous problem. In this paper, a teleoperation framework based on master–slave heterogeneous matching and nonlinear precise motion control for hydraulic manipulator is proposed, including workspace mapping algorithm, velocity-limited interpolator, inverse kinematics solver, trajectory planner, model-based controller, and feedback torque generator. The high-precision teleoperation of the hydraulic manipulator in the situation of master–slave heterogeneity is finally realized based on the designed teleoperation framework. The specialized experiment is set up, and the results also show that the method proposed in this paper can satisfy the teleoperation requirements of the hydraulic manipulator with the maximum operating accuracy up to 0.02 m under the condition of master–slave heterogeneity, which can greatly improve the applicability of hydraulic manipulator teleoperation in the case of master–slave heterogeneity.
Online Monitoring of Surface Quality for Diagnostic Features in 3D Printing
Authors: Lishchenko Natalia , Piteľ Ján , Larshin Vasily
Published: July 2022

Investigation into non-destructive testing and evaluation of 3D printing quality is relevant due to the lack of reliable methods for non-destructive testing of 3D printing defects, including testing of the surface quality of 3D printed parts. The article shows how it is possible to increase the efficiency of online monitoring of the quality of the 3D printing technological process through the use of an optical contactless high-performance measuring instrument. A comparative study of contact (R130 roughness tester) and non-contact (LJ-8020 laser profiler) methods for determining the height of irregularities on the surface of a steel reference specimen was performed. It was found that, in the range of operation of the contact method (Ra 0.03–6.3 µm and Rz 0.2–18.5 µm), the errors of the contactless method in determining the standard surface roughness indicators Ra and Rz were 23.7% and 1.6%, respectively. Similar comparative studies of contact and non-contact methods were performed with three defect-free samples made of plastic polylactic acid (PLA), with surface irregularities within the specified range of operation of the contact method. The corresponding errors increased and amounted to 65.96% and 76.32%. Finally, investigations were carried out using only the non-contact method for samples with different types of 3D printing defects. It was found that the following power spectral density (PSD) estimates can be used as diagnostic features for determining 3D printing defects: Variance and Median. These generalized estimates are the most sensitive to 3D printing defects and can be used as diagnostic features in online monitoring of object surface quality in 3D printing.
Understanding the Effect of Material Parameters on the Processability of Injection-Molded Thermoset-Based Bonded Magnets
Authors: Rösel Uta , Drummer Dietmar
Published: July 2022

The applications of bonded magnets in the field of injection-molded samples can be expanded by thermoset-based polymer-bonded magnets, as thermosets provide the opportunity to comply with the demands of, for example, the chemical industry or pump systems in drive applications through to their improved chemical and thermal resistance, viscosity and creep behaviour, especially compared to thermoplastic-based magnets. This paper investigates the influence of the matrix material (epoxy resin, phenolic resin), the filler type (strontium-ferrite-oxide, neodymium-iron-boron) and the filler grade on the reaction kinetics and the viscosity. Based on the determination of the impact, the theory of the network structure is founded. The network and the cross-linked structure are essential to know, as they significantly define not only the material but also the sample behaviour. The correlation between the material system and the mechanical as well as the magnetic properties is portrayed based on the general understanding of the behaviour in terms of the reaction kinetics and the viscosity as well as the theory of the network structure. With that, a basic understanding of the correlation within the material system (matrix, filler, filler grade) and between the reaction kinetics, the network and the cross-linked structure was determined, which gives the opportunity to change the mechanical and the magnetic properties based on the analyzed impact factors and to expand the applications of bonded magnets in the field of thermoset-based ones.
Semantic Image Segmentation Using Scant Pixel Annotations
Authors: Chakravarthy Adithi D. , Abeyrathna Dilanga , Subramaniam Mahadevan , Chundi Parvathi , Gadhamshetty Venkataramana
Published: July 2022

The success of deep networks for the semantic segmentation of images is limited by the availability of annotated training data. The manual annotation of images for segmentation is a tedious and time-consuming task that often requires sophisticated users with significant domain expertise to create high-quality annotations over hundreds of images. In this paper, we propose the segmentation with scant pixel annotations (SSPA) approach to generate high-performing segmentation models using a scant set of expert annotated images. The models are generated by training them on images with automatically generated pseudo-labels along with a scant set of expert annotated images selected using an entropy-based algorithm. For each chosen image, experts are directed to assign labels to a particular group of pixels, while a set of replacement rules that leverage the patterns learned by the model is used to automatically assign labels to the remaining pixels. The SSPA approach integrates active learning and semi-supervised learning with pseudo-labels, where expert annotations are not essential but generated on demand. Extensive experiments on bio-medical and biofilm datasets show that the SSPA approach achieves state-of-the-art performance with less than 5% cumulative annotation of the pixels of the training data by the experts.