bluuebunny/crossref_metadata_2025 huggingface dataset:
Essential Oils Reduce Grey Mould Rot of Apples and Modify the Fruit Microbiome during Postharvest Storage
Authors: Schiavon Giada , Garello Marco , Prencipe Simona , Meloni Giovanna Roberta , Buonsenso Fabio , Spadaro Davide
Published: December 2022

Botrytis cinerea is the causal agent of grey mould rot of apples. The efficacy of biofumigation with thyme (Thymus vulgaris), savoury (Satureja montana), and basil (Ocimum basilicum) essential oils (EOs) at 1%, 0.5%, and 0.1% concentrations were tested against B. cinerea. In vitro, the results showed 100% growth inhibition at 1% concentration for all oils. Subsequent biofumigation experiments on apples of cultivar ‘Opal’ with 1% EOs showed that, after 60 d storage, thyme and savoury EOs significantly reduced grey mould rot incidence (average incidence 2% for both treatments) compared to the control (7%). Analyses of quality indicated slightly higher fruit firmness for 1% thyme at 30 d and slightly higher titratable acidity for 1% thyme and savoury at 60 d. Sampling of the atmosphere inside the cabinets was performed to characterize and quantify the volatile components of EOs released through biofumigation. Though thymol and p-cymene were the main components of thyme EO, the antimicrobial activity was mainly due to the presence of thymol and, to a lower extent, of carvacrol. In savoury EO, carvacrol and p-cymene were the main components, whereas in basil EO, linalool and estragole were mainly present. Metabarcoding analyses showed that the epiphytic microbiome had higher richness and evenness compared to their endophytic counterpart. By the end of shelf-life, treatments with thyme EO reduced B. cinerea abundance compared to the inoculated control for both endophytes (from 36.5% to 1.5%) and epiphytes (from 7.0% to 0.7%), while favouring a significant increase in Penicillium species both in endophytes (from 0.2% to 21.5%) and epiphytes (from 0.5% to 18.6%). Results indicate that thyme EO (1%) and savoury EO (1%) are equally effective in hampering grey mould rot development in vivo.
Importance of Aspergillus-Specific Antibody Screening for Diagnosis of Chronic Pulmonary Aspergillosis after Tuberculosis Treatment: A Prospective Follow-Up Study in Ghana
Authors: Ocansey Bright K. , Otoo Benjamin , Gbadamosi Hafisatu , Afriyie-Mensah Jane S. , Opintan Japheth A. , Kosmidis Chris , Denning David W.
Published: December 2022

Chronic pulmonary aspergillosis (CPA) often occurs in patients that have been previously treated for pulmonary tuberculosis (PTB). A limited number of studies have looked at the development of CPA at different times following the completion of a PTB treatment course. This prospective longitudinal study aimed to determine the incidence of CPA at two timepoints, at the end of the PTB treatment (T1) and six months post-treatment (T2). Patients with confirmed PTB from a previous study who were placed on anti-TB medication were followed up and screened for CPA at T1 and T2 by assessing their symptoms, evaluating their quality of life, and screening them for Aspergillus infection by performing antibody testing and cultures. CPA was defined by the Global Action for Fungal Infections (GAFFI) diagnostic algorithm. Forty-one patients were enrolled, of whom thirty-three patients (80%) and twenty-eight patients (68%) were resurveyed at T1 and T2, respectively. The rate of new CPA was 3.3% (1/33) and 7.4% (2/27) at T1 and T2, respectively, with an overall incidence of 10.7% (3/28) among the patients at both T1 and T2. A positive Aspergillus-specific antibody test was an indicator for CPA in all three patients. Aspergillus-specific antibody screening during and after the end of an anti-TB treatment regimen may be important for early detection of CPA in high-PTB-burden settings.
“Spotify for News”? User Perception of Subscription-Based Content Platforms for News Media
Authors: Buschow Christopher , Wellbrock Christian-Mathias
Published: December 2022

Subscription-based news platforms (such as “Apple News+” or “Readly”) that bundle content from different publishers into one comprehensive package and offer it to media users at a fixed monthly rate are a new way of accessing and consuming digital journalism. These services have received little attention in journalism studies, although they differ greatly from traditional media products and distribution channels. This article empirically investigates the perception of journalism platforms based on eight qualitative focus group discussions with 55 German news consumers. Results show that the central characteristics these platforms should fulfill in order to attract users are strikingly similar to the characteristics of media platforms from the music and video industries, in particular regarding price points, contract features, and modes of usage. Against this background, the potential and perspectives of a subscription-based news platform for journalism’s societal role are discussed.
Advanced Strategy of Trophoblasts Retrieval and Isolation from the Cervix (TRIC): Comparison of Two HLA-G Antibodies for Immunomagnetic Isolation of Trophoblasts
Authors: Hong Kirim , Jang Hee Yeon , Shim Sung Han , Cho Hee Young , Cha Dong Hyun
Published: December 2022

Trophoblasts retrieval and isolation from the cervix (TRIC) is a non-invasive method which enables analysis of fetal genetic information from the extravillous trophoblast cells (EVTs). The aim of this study was to compare the efficacy of the HLA-G antibodies—G233 and 4H84—in isolating EVT cells and provide an optimized protocol of TRIC. We analyzed EVTs from 23 pregnant women in between 5 to 20 weeks of gestation who underwent invasive prenatal testing. Two HLA-G antibodies—G233 and 4H84—were used in a subgroup of 11 and 12 samples for immunomagnetic isolation. Cells with β-hCG expression were counted to compare the rate of isolated trophoblast cells. The rate of β-hCG positive cells was significantly different between the G233 and the 4H84 by immunefluorescence microscopy (p < 0.001). The percentage of β-hCG expressing cells in G233 and 4H84 groups were 62.4 ± 8.24% and 82.6 ± 7.1%, respectively (p < 0.001). The average fetal cell positive rate was 14.1 ± 3.78 in the G233 group while it was 25.8 ± 3.9 in the 4H84 group by fluorescence in situ hybridization (FISH) (p = 0.011). Immunoisolation of trophoblast cells using 4H84 HLA-G antibody was more efficient in capturing EVT cells than using G233 for successful clinical application of TRIC.
Do Foreign Investment Flow and Overconfidence Influence Stock Price Movement? A Comparative Analysis before and after the COVID-19 Lockdown
Authors: Sukmadilaga Citra , Fitri Almaida Noor , Ghani Erlane K.
Published: December 2022

This study examined whether foreign investment flow and overconfidence can influence stock price movement among the publicly listed companies in Indonesia. Subsequently, this study determined whether there was any significant difference in the influence of foreign investment flow and overconfidence on stock price movement before and after the COVID-19 lockdown in Indonesia. This study focused on the manufacturing companies listed on the Indonesian Stock Exchange for the 2020 period of which the data were taken in a period of 10 days before and 10 days after the implementation of the COVID-19 lockdown in Indonesia. Using content analysis on secondary data, this study showed that there was a significant difference between the stock prices before and after the COVID-19 lockdown. However, this study showed that foreign investment flow and overconfidence were not the main factors influencing stock price movement before and after the lockdown. The findings indicate that there are other factors that contribute to stock price movement in Indonesia. This study contributes to the existing literature on whether foreign investment flow and overconfidence influence stock price movement in a pandemic world.
Multifaceted Nutritional Disorders in Elderly Patients Undergoing Dialysis
Authors: Mori Katsuhito , Kurajoh Masafumi , Inaba Masaaki , Emoto Masanori
Published: December 2022

Advances in medicine have resulted in increased longevity, which has consequently led to unexpected geriatric syndromes, such as frailty and sarcopenia. Patients with end-stage kidney disease, especially those receiving dialysis treatment, often show characteristic reductions in body protein and energy storage, termed protein energy wasting (PEW). Therefore, maintenance of nutritional condition has a key role in defending against both geriatric syndromes and PEW, which share several components in elderly individuals undergoing hemodialysis. To counteract the development of an undesirable condition, nutritional evaluation is indispensable. In addition to simple measurements of body mass index, and serum albumin and creatinine, a composite nutritional assessment including a malnutrition inflammation score is useful, although subjective elements are included and a well-trained examiner is required. On the other hand, the geriatric nutritional risk index and nutritional risk index for Japanese hemodialysis patients (NRI-JH) are objective tools, and easy to use in clinical settings. Undernutrition is closely related to infectious events and the results of an infection are often serious in elderly patients, even those with survival, with large medical costs incurred. Together with appropriate nutritional evaluation, it is necessary to clarify the underlying relationship of PEW with infection for improvement of prognosis in affected elderly individuals.
What Is the Future of the Bush Capital? A Socio-Ecological Approach to Enhancing Canberra’s Green Infrastructure
Authors: Mofrad Fahimeh , Ignatieva Maria
Published: December 2022

Canberra, a city known as a “garden city” that emerged in the early twentieth century, is developing at a speedy rate. The compact city vision for Canberra was announced in ACT Planning Strategy 2018 while the city encounters climate change impacts. Although urban compaction has its own benefits, it is considered a challenge for maintaining and developing the quality and quantity of urban green spaces. Canberra owns a unique urban design legacy and is known for its bush capital/garden city character, which has intertwined the social and ecological layers of the city. The concern around urban compaction and densification calls for holistic green infrastructure (GI) planning to balance the built and non-built infrastructure. To do so, it is necessary to understand the underlying social-cultural and ecological layers of Canberra’s green spaces and the Ecosystem Services (ESS) they offer. The application of multiple ESS in the current GI planning and governance practices is another issue that needs to be examined to inform future development. Thus, this qualitative research seeks to understand the ESS discourses in Canberra’s GI and the challenges in applying these ESS in planning and governance. We used a socio-ecological approach to design the research and understand the multidimensional values and benefits of Canberra’s green spaces. We adopted semi-structured interviews with twelve experts from relevant disciplines with specific knowledge of Canberra’s urban landscape and green spaces to find out the socio-ecological synopsis of Canberra’s GI and green spaces governance. We found that it is necessary to mainstream multiple ESS in Canberra’s GI to amplify the existing socio-ecological values. The abundance of green spaces in Canberra can be better used to make a multifunctional landscape that serves multiple ESS. However, we identified the maintenance and budget issues as the main challenges that can be addressed by improving community engagement. To design an effective GI network and mainstream ESS in green spaces, the planning and governance system should employ a transdisciplinary, multi-object and multi-scale approach and state-of-the-art technologies. Moreover, this research underlined the importance of a protocol and guidelines that monitor the landscape projects’ design and delivery correspondence to the high-level policies.
On the Rhetorical Effectiveness of Implicit Meaning—A Pragmatic Approach
Authors: de Oliveira Fernandes Daniel , Oswald Steve
Published: December 2022

This paper explores the interface between pragmatics and argumentation by considering the impact of different types of implicit meaning on different types of rhetorical effects. On the rhetorical front and drawing on classical rhetoric but going beyond the Aristotelian rhetorical triangle (ethos, logos, pathos), the paper discusses an open list of rhetorical effects affecting speakers, audiences, messages and the conversational flow of interaction. On the pragmatic front, the paper accounts for how specific features of different types of implicit meaning (presupposition, implicature and back-door speech acts) are likely to trigger specific rhetorical effects. In so doing, it discusses and justifies the need for and the feasibility of an experimental investigation of the rhetorical effectiveness of implicit meaning.
Vocabulary Teaching in Refugee Children within the Context of the Greek Formal Education
Authors: Olioumtsevits Konstantina , Papadopoulou Despina , Marinis Theodoros
Published: December 2022

The aim of the present study is to investigate vocabulary teaching in children with refugee backgrounds. The effectiveness of three vocabulary interventions—flashcards, pantomime, and use of contextual cues—is examined within the context of formal primary education in Greece. The improvement of the children’s vocabulary is also assessed in association with factors related to the students’ background as well as factors related to the words taught. Thirty-three pupils from the second to the sixth primary school grade attended the teaching interventions. Their first languages are Arabic, Farsi, and Kurdish. According to the results, flashcards and pantomime significantly improve children’s second language vocabulary skills, while this finding does not apply to the intervention involving contextual cues. Age is found to play a role only in the latter intervention, while the effectiveness of no intervention was influenced by word category.
Role of ZNF143 and Its Association with Gene Expression Patterns, Noncoding Mutations, and the Immune System in Human Breast Cancer
Authors: Saddeek Salma , Almassabi Rehab , Mobashir Mohammad
Published: December 2022

The function of noncoding sequence variations at ZNF143 binding sites in breast cancer cells is currently not well understood. Distal elements and promoters, also known as cis-regulatory elements, control the expression of genes. They may be identified by functional genomic techniques and sequence conservation, and they frequently show cell- and tissue-type specificity. The creation, destruction, or modulation of TF binding and function may be influenced by genetic modifications at TF binding sites that affect the binding affinity. Therefore, noncoding mutations that affect the ZNF143 binding site may be able to alter the expression of some genes in breast cancer. In order to understand the relationship among ZNF143, gene expression patterns, and noncoding mutations, we adopted an integrative strategy in this study and paid close attention to putative immunological signaling pathways. The immune system-related pathways ErbB, HIF1a, NF-kB, FoxO, JAK-STAT, Wnt, Notch, cell cycle, PI3K–AKT, RAP1, calcium signaling, cell junctions and adhesion, actin cytoskeleton regulation, and cancer pathways are among those that may be significant, according to the overall analysis.
Dynamic Arterial Elastance to Predict Mean Arterial Pressure Decrease after Reduction of Vasopressor in Septic Shock Patients
Authors: Persona Paolo , Tonetti Tommaso , Valeri Ilaria , Pivetta Emanuele , Zarantonello Francesco , Pettenuzzo Tommaso , De Cassai Alessandro , Navalesi Paolo
Published: December 2022

After fluid status optimization, norepinephrine infusion represents the cornerstone of septic shock treatment. De-escalation of vasopressors should be considered with caution, as hypotension increases the risk of mortality. In this prospective observational study including 42 patients, we assess the role of dynamic elastance (EaDyn), i.e., the ratio between pulse pressure variation and stroke volume variation, which can be measured noninvasively by the MostCare monitoring system, to predict a mean arterial pressure (MAP) drop > 10% 30 min after norepinephrine reduction. Patients were divided into responders (MAP falling > 10%) and non-responders (MAP falling < 10%). The receiver-operating-characteristic curve identified an area under the curve of the EaDyn value to predict a MAP decrease > 10% of 0.84. An EaDyn cut-off of 0.84 predicted a MAP drop > 10% with a sensitivity of 0.71 and a specificity of 0.89. In a multivariate logistic regression, EaDyn was significantly and independently associated with MAP decrease (OR 0.001, 95% confidence interval 0.00001–0.081, p < 0.001). The nomogram model for the probability of MAP decrease > 10% showed a C-index of 0.90. In conclusion, in a septic shock cohort, EaDyn correlates well with the risk of decrease of MAP > 10% after norepinephrine reduction.
Professional Factors Associated with Case Resolution without Referrals of Orofacial Pain Cases to Secondary Dental Care by Telehealth in Brazil: A Cross-Sectional Study in 2019 and 2020
Authors: de Barreto Aranha Ricardo Luiz , de Castro Martins Renata , Paixão Ligia Cristelli , de Abreu Mauro Henrique Nogueira Guimarães
Published: December 2022

This study aimed to identify professional factors associated with case resolution without a referral of orofacial pain to secondary health care by Brazilian Primary Health Care (PHC) practitioners who demanded asynchronous teleconsulting, stratified by year, in 2019 and 2020 (the COVID-19 Pandemic burst). A cross-sectional study employed secondary databases from asynchronous teleconsulting Telehealth Brazil Networks from January 2019 to December 2020. The outcome was the dichotomous variable “If referral to secondary care was avoided.” As covariates: sex, healthcare professions, and category of orofacial pain doubts. A negative binomial regression model estimated each covariate’s unadjusted and adjusted PR (95%CI) and p values, stratified for 2019 and 2020. There was a difference in descriptive factors associated with case resolution without a referral from 2019 to 2020. Females prevailed in both years, and the total demand decreased to a third from 2019 to 2020. The rate of resoluteness decreased by 19.1%. In 2019, nurses (PR = 0.69 CI 95% 0.57–0.83) and other professionals (PR = 0.84 CI 95% 0.73–0.97) showed less frequency of case resolution without a referral than did general dentists. In 2020, oral-cavity-related doubts (PR = 1.18 CI 95% 1.06–1.32) and temporomandibular disorders (PR = 1.33 95% 1.15–1.54) surpassed other causes of orofacial pain in case resolution without a referral, and female professionals avoided referrals more frequently than men (PR = 1.24 CI 95% 1.21–1.38). In conclusion, in 2019, oral cavity doubts and the PHC profession influenced the case resolution. Female professionals and oral cavity doubts scored the higher case resolution without a referral for the service in 2020.
Photon- and Proton-Mediated Biological Effects: What Has Been Learned?
Authors: Jumaniyazova Enar , Smyk Daniil , Vishnyakova Polina , Fatkhudinov Timur , Gordon Konstantin
Published: December 2022

The current understanding of the effects of radiation is gradually becoming broader. However, it still remains unclear why some patients respond to radiation with a pronounced positive response, while in some cases the disease progresses. This is the motivation for studying the effects of radiation therapy not only on tumor cells, but also on the tumor microenvironment, as well as studying the systemic effects of radiation. In this framework, we review the biological effects of two types of radiotherapy: photon and proton irradiations. Photon therapy is a commonly used type of radiation therapy due to its wide availability and long-term history, with understandable and predictable outcomes. Proton therapy is an emerging technology, already regarded as the method of choice for many cancers in adults and children, both dosimetrically and biologically. This review, written after the analysis of more than 100 relevant literary sources, describes the local effects of photon and proton therapy and shows the mechanisms of tumor cell damage, interaction with tumor microenvironment cells and effects on angiogenesis. After systematic analysis of the literature, we can conclude that proton therapy has potentially favorable toxicological profiles compared to photon irradiation, explained mainly by physical but also biological properties of protons. Despite the fact that radiobiological effects of protons and photons are generally similar, protons inflict reduced damage to healthy tissues surrounding the tumor and hence promote fewer adverse events, not only local, but also systemic.
Dysbiotic Gut Microbiota Modulation by Aronia Fruits Extract Administration
Authors: Vamanu Emanuel , Gatea Florentina , Avram Ionela , Radu Gabriel Lucian , Singh Sandeep Kumar
Published: December 2022

The administration of chokeberry extract in vitro in the GIS1 system was evaluated for the modulation capacity of the dysbiotic pattern resulting from the consumption of stevia. The microbial pattern determined by molecular method, the metabolomic one (fatty acids), the evolution of the antioxidant status, and the cytotoxic effect were determined comparatively for six months. This study presented for the first time that Aronia extract has a strong antimicrobial effect but also a presence of new organic acids that can be used as a biomarker. The functional supplement had the impact of a gradual increase in antioxidant status (DPPH scavenging activity) for up to three months and a subsequent decrease correlated with the reduction of the microbial load (especially for Enterobacteriaceae). The effect on metabolomic activity was specific, with butyric acid being generally unaffected (0.6–0.8 mg/mL) by the antimicrobial effect manifested after three months of administration. The pH was strongly acidic, corresponding to the constant presence of maximum values for acetic and lactic acid. The non-selective elimination of a part of the microbiota could also be correlated with a decrease in metabolomic efficiency. The results in the GIS1 system indicated for the first time that the controlled use of this extract had a pronounced antimicrobial and cytotoxic effect. This has helped to correct the dysbiotic pattern that results after the long-term use of sweeteners based on an increase of 0.2 log UFC/mL for favorable strains.
Sympatho-Vagal Dysfunction in Systemic Sclerosis: A Follow-Up Study
Authors: Rodrigues Gabriel Dias , Carandina Angelica , Scatà Costanza , Bellocchi Chiara , Beretta Lorenzo , da Silva Soares Pedro Paulo , Tobaldini Eleonora , Montano Nicola
Published: December 2022

Systemic sclerosis (SSc) patients often present cardiovascular autonomic dysfunction, which is associated with the risk of arrhythmic complications and mortality. However, little is known regarding the progression of cardiac autonomic impairment over time. We aimed to evaluate the cardiac autonomic modulation among SSc with limited cutaneous (lcSSc), diffuse cutaneous (dcSSc) subset, and age-matched healthy control (HC) at baseline (t0) and five-year follow-up (t1). In this follow-up study, ECG was recorded at t0 and t1 in twenty-four SSc patients (dcSSc; n = 11 and lcSSc; n = 13) and 11 HC. The heart rate variability (HRV) analysis was conducted. The spectral analysis identified two oscillatory components, low frequency (LF) and high frequency (HF), and the sympatho-vagal balance was assessed by the LF/HF ratio. The LF/HF increased (p = 0.03), and HF reduced at t1 compared to t0 in dcSSc (p = 0.03), which did not occur in the lcSSc and HC groups. Otherwise, both lcSSc and dcSSc groups presented augmented LF/HF at t0 and t1 compared to HC (p < 0.01). In conclusion, a worsening of cardiac autonomic dysfunction is related to the dcSSc subset, in which a more extent of skin fibrosis and internal organs fibrosis is present.
Thermodynamic Analysis of the Solubility of Sulfadiazine in (Acetonitrile 1-Propanol) Cosolvent Mixtures from 278.15 K to 318.15 K
Authors: Trujillo-Trujillo Carlos Francisco , Angarita-Reina Fredy , Herrera Mauricio , Ortiz Claudia Patria , Cardenas-Torres Rossember Edén , Martinez Fleming , Delgado Daniel Ricardo
Published: December 2022

Drug solubility is one of the most significant physicochemical properties as it is related to drug design, formulation, quantification, recrystallization, and other processes, so understanding it is crucial for the pharmaceutical industry. In this context, this research presents the thermodynamic analysis of the solubility of sulfadiazine (SD) in cosolvent mixtures {acetonitrile + 1-propanol} at 9 temperatures (278.15 K–318.15 K), which is a widely used drug in veterinary therapy, and two solvents of high relevance in the pharmaceutical industry, respectively. The solubility of SD, in cosolvent mixtures {acetonitrile + 1-propanol} is an endothermic process where the maximum solubility was reached in pure acetonitrile at 318.15 K and the minimum in 1-propanol at 278.15 K. Although the solubility parameters of acetonitrile and propanol were similar, the addition of acetonitrile to the cosolvent mixture leads to a positive cosolvent effect on the solubility of DS. As for the thermodynamic functions of the solution, the process is strongly influenced by enthalpy, and according to the enthalpy–entropy compensation analysis, the process is enthalpy-driven in intermediate to rich mixtures in 1-propanol and entropy-driven in mixtures rich in acetonitrile.
Comparing the Corrosion Resistance of 5083 Al and Al2O33D/5083 Al Composite in a Chloride Environment
Authors: Yu Liang , Zhang Chen , Liu Yuan , Yan Yulong , Xu Pianpian , Jiang Yanli , Cao Xiuling
Published: December 2022

In this study, an Al2O33D/5083 Al composite was fabricated by infiltrating a molten 5083 Al alloy into a three-dimensional alumina reticulated porosity ceramics skeleton preform (Al2O33D) using a pressureless infiltration method. The corrosion resistance of 5083 Al alloy and Al2O33D/5083 Al in NaCl solution were compared via electrochemical impedance spectroscopy (EIS), dynamic polarization potential (PDP), and neutral salt spray (NSS) tests. The microstructure of the two materials were investigated by 3D X-ray microscope and scanning electron microscopy aiming at understanding the corrosion mechanisms. Results show that an Al2O33D/5083 Al composite consists of interpenetrating structure of 3D-continuous matrices of continuous networks 5083 Al alloy and Al2O33D phase. A large area of strong interfaces of 5083 Al and Al2O33D exist in the Al2O33D/5083 Al composite. The corrosion development process can be divided into the initial period, the development period, and the stability period. Al2O33D used as reinforcement in Al2O33D/5083 Al composite improves the corrosion resistance of Al2O33D/5083 Al composite via electrochemistry tests. Thus, the corrosion resistance of Al2O33D/5083 Al is higher than that of 5083 Al alloy. The NSS test results indicate that the corrosion resistance of Al2O33D/5083 Al was lower than that of 5083 Al alloy during the initial period, higher than that of 5083 Al alloy during the development period, and there was no obvious difference in corrosion resistance during the stability period. It is considered that the elements in 5083 Al alloy infiltrated into the Al2O33D/5083 Al composite are segregated, and the uniform distribution of the segregated elements leads to galvanic corrosion during the corrosion initial period. The perfect combination of interfaces of Al2O33D and the 5083 Al alloy matrix promotes excellent corrosion resistance during the stability period.
Experimental Measurement of Deposition Chloride Ions in the Vicinity of Road Cut
Authors: Vacek Miroslav , Křivý Vít , Kreislová Kateřina , Vlachová Markéta , Kubzová Monika
Published: December 2022

Chloride ions are nowadays the main cause of the degradation of steel and reinforce concrete construction in the vicinity of the road. On the other hand, chloride ions, usually in the form of de-icing salts or brine, are very important for safe winter traffic on the roads. This creates a slightly schizophrenic situation where it is necessary to ensure safe traffic in the winter period and at the same time to affect the service life of the structure as little as possible. The effect of the roadway on chloride deposition is a long-studied, but still imprecisely understood, part of the effect of chloride ions on structures in the vicinity of the roadway. This paper discusses the experimental measurement of chloride deposition in the vicinity of the I/11 road in the Czech Republic by dry plate method, wet candle method and corrosion coupons. Statistical analysis of correlation and regression is performed on the results of measurements by wet candle and horizontal dry plate methods. The methods are interdependent. A detailed analysis of the surface and chemical properties of the corrosion products is performed on the corrosion coupons. Using the corrosion loss, the environmental category C2 is determined. Observation of the microclimate in the vicinity of the roads gives to engineers a basis for the correct design of structures around the roads. The conclusions of the experimental measurements are intended to help engineers to design a structure that is safe, serviceable and sufficiently resistant to chloride ions within its service life
Study on Influencing Factors of Ground Pressure Behavior in Roadway-Concentrated Areas under Super-Thick Nappe
Authors: Zhu Ruojun , Yue Xizhan , Liu Xuesheng , Shi Zhihan , Li Xuebin
Published: December 2022

During the mining activity under the super-thick nappe formed by thrust fault, the law of mine pressure behavior is complex, and it is difficult to control the deformation and failure of surrounding rock. Combined with the actual engineering conditions, the influence of different roof lithology conditions, the thickness of nappe, the mining height, the size of the barrier coal pillar, and the creep time on mine pressure behavior was studied by UDEC numerical simulation software. The results showed that with the advancement of the coal face, due to the influence of the mining of the coal face and the slip dislocation of the super-thick nappe along the thrust faults, the roof-to-floor convergence, the two-sided convergence, and the maximum concentrated stress in the roadway-concentrated areas are significantly increased. For the above five influencing factors, the greater the thickness of the nappe and the mining height, the longer the creep time, and the stronger the ground pressure behavior. The larger the size of the barrier coal pillar, the stronger the roof lithology, and the gentler the ground pressure behavior. The research results can provide some reference for monitoring the law of ground pressure behavior in roadway-concentrated areas under super-thick nappe.
The Use of Hybrid Genetic Algorithm in the Kinetic Analysis of Thermal Decomposition of [Ni(C2H8N2)3](ClO4)2 with Overlapping Stages
Authors: Dmitruk Kirill A. , Komova Oksana V. , Paletsky Alexander A. , Shmakov Andrey G. , Mukha Svetlana A. , Butenko Vladislav R. , Pochtar Alena A. , Netskina Olga V.
Published: December 2022

This work describes the mathematical modeling of the thermal decomposition of the complex compound [Ni(En)3](ClO4)2 (En = C2H8N2 = ethylenediamine) in an inert atmosphere under non-isothermal conditions. This process is characterized by several simultaneous and intense stages: elimination of ethylenediamine from the nickel coordination sphere, decomposition of perchlorate anions, and explosive-like oxidation of free or bound ethylenediamine. These stages overlap and merge into a one step on the differential thermogravimetric curve. Typically, this curve is modeled as a one-stage process during kinetic analysis. In this paper, for the first time, the data from the dynamic mass-spectral thermal analysis and thermogravimetric analysis were modeled using the hybrid genetic algorithm, and the results were compared. A two-stage scheme of [Ni(En)3](ClO4)2 thermolysis was proposed and the kinetic parameters for each stage were obtained. It was shown that the decomposition of [Ni(En)3](ClO4)2 begins with the elimination of one molecule of ethylenediamine (stage A), then the perchlorate anions quickly decompose with the evolution of oxygen (stage B). We believe that the resulting ClO4−x− (x = 1–3), as stronger oxidizing agents, instantly start an explosive-like exothermic process of ethylenediamine oxidation (stage B).
Experimental Analysis and Parametric Optimization on Compressive Properties of Diamond-Reinforced Porous Al Composites
Authors: Parveez Bisma , Jamal Nur Ayuni , Aabid Abdul , Baig Muneer , Yusof Farazila
Published: December 2022

The present study aims to optimize the compressive properties of porous aluminum composites fabricated using the powder metallurgy (PM) space holder technique. These properties were optimized by taking into consideration different processing factors such as sintering temperature, compaction pressure, and sintering time. The experimental design was formulated using L9 orthogonal array by employing these three parameters at three levels. The density, porosity, plateau stress, and energy absorption capacity were determined and analyzed. The impact of individual input parameters was evaluated using the Taguchi-based S/N ratio and analysis of variance (ANOVA). The main effect plots outlined the optimum parameter levels to achieve maximum values for compressive properties (plateau stress and energy absorption capacity). The results revealed that the sintering temperature and time significantly impact compressive properties. The ANOVA analysis exhibited similar results, with maximum contribution from sintering temperature. Further response optimization of compressive properties concluded that the maximum values could be achieved at optimum parameters, i.e., a sintering temperature of 590 °C, compaction pressure of 350 MPa, and sintering time of 90 min. Further, confirmation tests on the optimized parameters revealed improved results and some minor errors and deviations indicating that the selected parameters are vital for controlling the compressive properties of the aluminum composites.
Mathematical Models for Machining Optimization of Ampcoloy 35 with Different Thicknesses Using WEDM to Improve the Surface Properties of Mold Parts
Authors: Mouralova Katerina , Bednar Josef , Benes Libor , Prokes Tomas , Zahradnicek Radim , Fries Jiri
Published: December 2022

Wire electrical discharge machining (WEDM) is an unconventional machining technology that can be used to machine materials with minimum electrical conductivity. The technology is often employed in the automotive industry, as it makes it possible to produce mold parts of complex shapes. Copper alloys are commonly used as electrodes for their high thermal conductivity. The subject of this study was creating mathematical models for the machining optimization of Ampcoloy 35 with different thicknesses (ranging from 5 to 160 mm with a step of 5 mm) using WEDM to improve the surface properties of the mold parts. The Box–Behnken type experiment was used with a total of 448 samples produced. The following machining parameters were altered over the course of the experiment: the pulse on and off time, discharge current, and material thickness. The cutting speed was measured, and the topography of the machined surfaces in the center and at the margins of the samples was analyzed. The morphology and subsurface layer were also studied. What makes this study unique is the large number of the tested thicknesses, ranging from 5 to 160 mm with a step of 5 mm. The contribution of this study to the automotive industry and plastic injection mold production is, therefore, significant. The regression models for the cutting speed and surface topography allow for efficient defect-free machining of Ampcoloy 35 of 5–160 mm thicknesses, both on the surface and in the subsurface layer.
Resolving Salt-Induced Agglomeration of Laponite Suspensions Using X-ray Photon Correlation Spectroscopy and Molecular Dynamics Simulations
Authors: Mohammed Sohaib , Liu Meishen , Zhang Qingteng , Narayanan Suresh , Zhang Fan , Gadikota Greeshma
Published: December 2022

Linking the physics of the relaxation behavior of viscoelastic fluids as they form arrested gel states to the underlying chemical changes is essential for developing predictive controls on the properties of the suspensions. In this study, 3 wt.% laponite suspensions are studied as model systems to probe the influence of salt-induced relaxation behavior arising from the assembly of laponite nanodisks. X-ray Photon Correlation Spectroscopy (XPCS) measurements show that laponite suspensions prepared in the presence of 5 mM concentrations of CaCl2, MgCl2 and CsCl salts accelerate the formation of arrested gel states, with CaCl2 having a significant impact followed by CsCl and MgCl2 salts. The competing effects of ion size and charge on relaxation behavior are noted. For example, the relaxation times of laponite suspensions in the presence of Mg2+ ions are slower compared to Cs+ ions despite the higher charge, suggesting that cation size dominates in this scenario. The faster relaxation behavior of laponite suspensions in the presence of Ca2+ ions compared to Cs+ ions shows that a higher charge dominates the size of the ion. The trends in relaxation behavior are consistent with the cluster formation behavior of laponite suspensions and the electrostatic interactions predicted from MD simulations. Charge balance is achieved by the intercalation of the cations at the negatively charged surfaces of laponite suspensions. These studies show that the arrested gel state of laponite suspensions is accelerated in the presence of salts, with ion sizes and charges having a competing effect on relaxation behavior.
Biomechanical Comparison of WE43-Based Magnesium vs. Titanium Miniplates in a Mandible Fracture Model in Sheep
Authors: Fischer Heilwig , Schmidt-Bleek Oskar , Orassi Vincenzo , Wulsten Dag , Schmidt-Bleek Katharina , Heiland Max , Steffen Claudius , Rendenbach Carsten
Published: December 2022

In fractures of the mandible, osteosynthesis with titanium plates is considered the gold standard. Titanium is an established and reliable material, its main disadvantages being metal artefacts and the need for removal in case of osteosynthesis complications. Magnesium, as a resorbable material with an elastic modulus close to cortical bone, offers a resorbable alternative osteosynthesis material, yet mechanical studies in mandible fracture fixation are still missing. The hypothesis of this study was that magnesium miniplates show no significant difference in the mechanical integrity provided for fracture fixation in mandible fractures under load-sharing indications. In a non-inferiority test, a continuous load was applied to a sheep mandible fracture model with osteosynthesis using either titanium miniplates of 1.0 mm thickness (Ti1.0), magnesium plates of 1.75 mm (Mg1.75), or magnesium plates of 1.5 mm thickness (Mg1.5). No significant difference (p > 0.05) was found in the peak force at failure, stiffness, or force at vertical displacement of 1.0 mm between Mg1.75, Mg1.5, and Ti1.0. This study shows the non-inferiority of WE43 magnesium miniplates compared to the clinical gold standard titanium miniplates.
Drilling Strategies to Improve the Geometrical and Dimensional Accuracy of Deep through Holes Made in PA6 Alloy
Authors: Bronis Mateusz , Miko Edward , Nozdrzykowski Krzysztof
Published: December 2022

This article shows how different drilling strategies may affect the geometrical and dimensional accuracy of deep through holes. The tests were conducted on a three-axis direct-drive turning center. The holes were drilled in cylindrical PA6 aluminum alloy specimens 30 mm in length and 30 mm in diameter using 6 mm Ø VHM HPC TiAlN-coated twist drill bits. The cutting fluid was supplied to the cutting zone through the spindle. The experiments involved applying three strategies to drill deep through (5D) holes. The first required the workpiece to be fixed and the tool to perform both rotary and reciprocating motions. The second assumed that the workpiece performed the primary (rotary) motion whereas the tool moved in reciprocating motion. In the third strategy, the workpiece and the tool rotated in opposite directions and the tool also performed a reciprocating motion. The straightness, roundness, cylindricity, and diameter errors were the key output parameters in the analysis of the geometrical and dimensional accuracy of holes. The Taguchi orthogonal array design of experiment (DOE) was employed to determine the effects of the input (cutting) parameters (i.e., spindle speed and feed per revolution) and the type of hole making strategy on the hole errors by means of multi-factor statistical analysis ANOVA. The use of the highest spindle speed (n = 4775 rpm), the highest feed per revolution (fn = 0.14 mm/rev) and strategy I resulted in the lowest values of the output parameters (STR = 22.7 µm, RON = 8.6 µm, CYL = 28.2 µm, and DE = 9.9 µm). Strategy I was reported to be the most effective for hole drilling in PA6 aluminum alloy because, irrespective of the values of the process parameters used, three out of four output parameters, i.e., straightness, roundness and diameter errors, reached the lowest values.
Research of Low-Temperature Performance of Polyphosphoric Acid-Modified Asphalt
Authors: Wei Jianguo , Huang Meiyan , Zhou Yuming , Li Ping , Yu Fan , Ju Haolong , Shi Song
Published: December 2022

Polyphosphoric acid (PPA) modifier, which can effectively improve the rheological properties of asphalt, is widely used in pavement engineering. In order to accurately evaluate the low-temperature performance of PPA-modified asphalt, in this study, PPA-modified asphalt and PPA/SBR-modified asphalt were prepared. The modification mechanism was explored by scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FTIR). Bending Beam Rheology (BBR) test was carried out, and four indexes, including K index, viscous flow (η1), low-temperature integrated flexibility (Jc), and relaxation time (λ), were obtained by combining the Burgers model. The optimal low-temperature performance evaluation index of modified asphalt was determined by the analytic hierarchy process (AHP). The test results show that PPA addition to asphalt will produce chemical reactions, which can effectively improve the compatibility between SBR and neat asphalt. In the multi-index evaluation based on K, η1, Jc, and λ, the same optimum content of PPA was obtained. AHP analysis further demonstrates that Jc is the optimal evaluation index for laboratory research on the low-temperature performance of PPA-modified asphalt, and λ index is the ideal evaluation index for the low-temperature performance of asphalt in engineering applications.
How the Duration and Mode of Photopolymerization Affect the Mechanical Properties of a Dental Composite Resin
Authors: Szalewski Leszek , Wójcik Dorota , Sofińska-Chmiel Weronika , Kuśmierz Marcin , Różyło-Kalinowska Ingrid
Published: December 2022

Composite materials are the most common materials in use in modern dentistry. Over the years, the methods of photopolymerization of composite materials have been improved with the use of various devices, such as quartz tungsten halogen lamps (QTHs), light-emitting diode units (LEDs), plasma-arc lamps and argon-ion lasers. This study aimed to compare the mechanical properties of a composite material, depending on the time and mode of photopolymerization. One hundred and forty rectangular specimens (25 × 2 × 2 mm) and forty-two disc-shaped samples (5 mm diameter and 2 mm thickness) were prepared from shade A2 Boston composite resin. Samples were cured using the following seven photopolymerization protocols: four fast-cure modes (full power for 3, 5, 10, and 20 s), two pulse-cure modes (5 and 10 shots of 1 s exposures at full power), and one step-cure mode (soft start with a progressive cycle lasting 9 s). Specimens were subjected to a flexural strength test, Vickers microhardness test, and FTIR spectroscopy test. A 2-factor ANOVA and post-hoc tests were carried out to assess the differences in the flexural strength parameter between the tested groups of samples before and after aging. A mixed-model ANOVA was carried out to assess the differences in the Vickers microhardness parameter between the tested groups of samples before and after aging. The lowest values of flexural strength (p < 0.001) and Vickers microhardness (p < 0.001) were obtained for the 3 s mode for the pre- and post-aging groups. The FTIR mapping tests showed a much more homogeneous chemical structure of the composite after 20 s of continuous irradiation, compared to the sample irradiated for 5 s in the continuous mode. The mode and cure time affects the mechanical properties of the composite resin. Appropriate selection of the cure mode and time ensures better mechanical properties of composite resin. This suggests that the survival of dental restorations within the oral cavity could be extended by using longer photopolymerization durations.
Optimization of WEDM Parameters While Machining Biomedical Materials Using EDAS-PSO
Authors: Sharma Vishal S. , Sharma Neeraj , Singh Gurraj , Gupta Munish Kumar , Singh Gurminder
Published: December 2022

In the present work, an attempt has been made to study the influence of process parameters of the wire electric discharge machining (WEDM) process on the machining characteristics. The commercially pure titanium is machined by WEDM using brass wire as an electrode. The input parameters in this work were pulse on-time (Aon), pulse off-time (Aoff), servo voltage (SV) and wire tension (WT). On the other hand, dimensional accuracy (DA), average surface roughness (Ra) and maximum surface roughness (Rz) were chosen as the response parameters. The empirical relations developed for response characteristics were solved collectively using Evaluation Based on Distance from Average Solution (EDAS) and Particle Swarm Optimization (PSO). The optimized setting for minimizing the surface irregularities while machining titanium alloy on WEDM is predicted as Aon: 8 μs; Aoff: 13 μs; SV: 45 V; and WT: 8 N. Moreover, the predicted solution at the optimized parametric settings came out as DA: 95%; Ra: 3.163 μm; Rz: 22.99 μm; WL: 0.0182 g; and DR: 0.1277 mm. The validation experiments at the optimized setting showed the close agreement between predicted and experimental values. The morphological study by scanning electron microscopy (SEM) at the optimized setting revealed a significant reduction in surface defects such as micro cracks, micro cavities, globules and sub-surfaces, etc. In a nutshell, the study justified the effectiveness of EDAS-PSO in efficiently predicting the results for machining of pure titanium (Grade 2) using the WEDM process.