bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of Fatigue Damage Initiation in Short Fiber-Reinforced Thermoplastic through Acoustic Emission Analysis
Authors: Krummenacker Janna , Hausmann Joachim
Published: August 2021

This study investigates the damage initiation in short glass fiber-reinforced polyamide 6.6 under fatigue loading using acoustic emission analysis. An optimized specimen geometry was developed to meet the specific requirements of this testing method, at the same time allowing further micromechanical studies. Specimens were preloaded with tensile–tensile fatigue loading, varying the maximum stress and the number of load cycles. Subsequently, the acoustic emission signals in residual strength tests were compared to those of undamaged specimens. The idea behind this approach is that only the damage that has not already occurred under fatigue load can be recorded in the residual strength tests. Using the analysis of acoustic energy, a stress threshold for damage initiation was identified. Furthermore, with tension–tension fatigue tests, the SN curve of the material was determined to estimate the lifetime for the identified stress threshold. The presented approach allows us to estimate a so-called endurance limit of short glass fiber-reinforced polyamide 6.6.
A Virtual Reality System for Improved Image-Based Planning of Complex Cardiac Procedures
Authors: Deng Shujie , Wheeler Gavin , Toussaint Nicolas , Munroe Lindsay , Bhattacharya Suryava , Sajith Gina , Lin Ei , Singh Eeshar , Chu Ka Yee Kelly , Kabir Saleha , Pushparajah Kuberan , Simpson John M. , Schnabel Julia A. , Gomez Alberto
Published: August 2021

The intricate nature of congenital heart disease requires understanding of the complex, patient-specific three-dimensional dynamic anatomy of the heart, from imaging data such as three-dimensional echocardiography for successful outcomes from surgical and interventional procedures. Conventional clinical systems use flat screens, and therefore, display remains two-dimensional, which undermines the full understanding of the three-dimensional dynamic data. Additionally, the control of three-dimensional visualisation with two-dimensional tools is often difficult, so used only by imaging specialists. In this paper, we describe a virtual reality system for immersive surgery planning using dynamic three-dimensional echocardiography, which enables fast prototyping for visualisation such as volume rendering, multiplanar reformatting, flow visualisation and advanced interaction such as three-dimensional cropping, windowing, measurement, haptic feedback, automatic image orientation and multiuser interactions. The available features were evaluated by imaging and nonimaging clinicians, showing that the virtual reality system can help improve the understanding and communication of three-dimensional echocardiography imaging and potentially benefit congenital heart disease treatment.
Two Cheers for the Cognitive Irregulars: Intelligence’s Contributions to Ageing Well and Staying Alive
Authors: Deary Ian J.
Published: August 2021

Here, intelligence is taken to mean scores from psychometric tests of cognitive functions. This essay describes how cognitive tests offer assessments of brain functioning—an otherwise difficult-to-assess organ—that have proved enduringly useful in the field of health and medicine. The two “consequential world problems” (the phrase used by the inviters of this essay) addressed in this article are (i) the ageing of modern societies (and the resulting increase in the numbers of people with ageing-related cognitive decrements and dementias) and (ii) health inequalities, including mortality. Cognitive tests have an ubiquitous place in both of these topics, i.e., the important fields of cognitive ageing and cognitive epidemiology, respectively. The cognitive tests that have sprouted in these fields are often brief and not mainstream, large psychometric test batteries; I refer to them as ‘irregulars’. These two problems are not separate, because results found with mental/cognitive/intelligence tests have produced a growing understanding that intelligence and health have a reciprocal, life-long relationship. Intelligence tests contribute to the applied research that is trying to help people to stay sharp, stay healthy, and stay alive.
A Modelling Approach for the Assessment of Wave-Currents Interaction in the Black Sea
Authors: Causio Salvatore , Ciliberti Stefania A. , Clementi Emanuela , Coppini Giovanni , Lionello Piero
Published: August 2021

In this study, we investigate wave-currents interaction for the first time in the Black Sea, implementing a coupled numerical system based on the ocean circulation model NEMO v4.0 and the third-generation wave model WaveWatchIII v5.16. The scope is to evaluate how the waves impact the surface ocean dynamics, through assessment of temperature, salinity and surface currents. We provide also some evidence on the way currents may impact on sea-state. The physical processes considered here are Stokes–Coriolis force, sea-state dependent momentum flux, wave-induced vertical mixing, Doppler shift effect, and stability parameter for computation of effective wind speed. The numerical system is implemented for the Black Sea basin (the Azov Sea is not included) at a horizontal resolution of about 3 km and at 31 vertical levels for the hydrodynamics. Wave spectrum has been discretised into 30 frequencies and 24 directional bins. Extensive validation was conducted using in-situ and satellite observations over a five-year period (2015–2019). The largest positive impact of wave-currents interaction is found during Winter while the smallest is in Summer. In the uppermost 200 m of the Black Sea, the average reductions of temperature and salinity error are about −3% and −6%, respectively. Regarding waves, the coupling enhanced the model skill, reducing the simulation error, about −2%.
Breast Cancer Treatments: Updates and New Challenges
Authors: Burguin Anna , Diorio Caroline , Durocher Francine
Published: August 2021

Breast cancer (BC) is the most frequent cancer diagnosed in women worldwide. This heterogeneous disease can be classified into four molecular subtypes (luminal A, luminal B, HER2 and triple-negative breast cancer (TNBC)) according to the expression of the estrogen receptor (ER) and the progesterone receptor (PR), and the overexpression of the human epidermal growth factor receptor 2 (HER2). Current BC treatments target these receptors (endocrine and anti-HER2 therapies) as a personalized treatment. Along with chemotherapy and radiotherapy, these therapies can have severe adverse effects and patients can develop resistance to these agents. Moreover, TNBC do not have standardized treatments. Hence, a deeper understanding of the development of new treatments that are more specific and effective in treating each BC subgroup is key. New approaches have recently emerged such as immunotherapy, conjugated antibodies, and targeting other metabolic pathways. This review summarizes current BC treatments and explores the new treatment strategies from a personalized therapy perspective and the resulting challenges.
Kinesio Taping vs. Auricular Acupressure for the Personalised Treatment of Primary Dysmenorrhoea: A Pilot Randomized Controlled Trial
Authors: Mejías-Gil Elena , Garrido-Ardila Elisa María , Montanero-Fernández Jesús , Jiménez-Palomares María , Rodríguez-Mansilla Juan , González López-Arza María Victoria
Published: August 2021

Background: Dysmenorrhoea is the medical term for menstrual pain. The World Health Organization estimates that up to 81% of women of childbearing age are affected by this condition, and it is one of the leading causes of absenteeism from work and school among women. Although there are pharmacological treatments available for menstrual-pain relief, they do not respond to all women’s needs. Therefore, there is a need to study and develop non-pharmacological alternatives to broaden the individualised treatment options for dysmenorrhea. There are scarce studies published on non-pharmacological treatments, such as kinesio tape and auricular acupressure for the relief of menstrual pain, but the scientific evidence available suggest that these techniques may be beneficial in addressing this problem. The objective of this pilot study was to assess and compare the effectiveness of kinesio tape and auricular acupressure to decrease pain and drug intake in women with primary dysmenorrhoea. Methods: This was a double-blind randomized clinical controlled trial. The period of study was from September 2017 to August 2018. Women enrolled in the University of Extremadura and who had primary dysmenorrhoea were randomized to five groups: control (n = 23), kinesio tape (n = 23), placebo kinesio tape (n = 23), auricular acupressure (n = 23) and placebo auricular acupressure (n = 22). Measures were taken during the pretreatment phase (at four menstrual cycles), during the post-intervention phase (at four menstrual cycles) and during the follow-up phase (at the first and third menstrual cycles after the treatment was completed). The primary outcome measures were mean pain intensity, maximum pain intensity, number of painful days and dose of drug intake during menstruation, measured with the Visual Analogue Scale. The secondary outcome measures were the length of the cycle, the length of menstruation, the drug intake and the type of drug. Results: In all, 108 participants completed the study. The statistical analysis (MANOVA, ANOVA, t-paired and McNemar tests) showed that kinesio tape and auricular acupressure have a beneficial effect on pain relief (mean pain intensity, p < 0.001; maximum pain intensity, p < 0.001; number of painful days, p = 0.021; dose of drug intake, p < 0.001). In addition, once the treatments were withdrawn, the auricular-acupressure group maintained lower scores during the first follow-up cycle (p < 0.001). Conclusions: Kinesio tape and auricular acupressure decrease pain and drug intake in women with primary dysmenorrhoea. The changes in the auricular-acupressure group seemed to last longer. The results suggest that these techniques could be used as complementary personalised therapies to the pharmacological treatment and not as a substitution.
Development of Social Cost and Benefit Analysis (SCBA) in the Maqāṣid Shariah Framework: Narratives on the Use of Drones for Takaful Operators
Authors: Muhamat Amirul Afif , Zulkifli Ahmad Farouk , Sulaiman Suzana , Subramaniam Geetha , Mohamad Saadiah
Published: August 2021

Takaful operators are part of the Islamic financial institutions that are expected to achieve the commercial and social objectives by their stakeholders particularly the takaful participants (policyholders). First, this study aims to postulate a new framework to measure cost effectiveness by including the social and economic benefits of drone-assisted technology in the context of maqāṣid Shariah. Second, the study intends to investigate how the takaful industry can benefit from the drone-assisted technology, particularly in terms of cost reduction. This paper presents an early finding that forms part of a bigger research project which is focusing on the use of drone for disaster victim identification (DVI). This study employs thematic analysis of qualitative research method by engaging key informants who are Shariah expert, drone practitioner and accounting expert. In the context of emerging economies like Malaysia, the adoption of drone is sporadic when some industries such as military and agriculture are quite experienced with it; but for the takaful sector is almost none. This study provides preliminary findings that suggests there is potential of cost effectiveness for drone usage from the perspectives of SCBA in the maqāṣid Shariah framework. The main contributions from this paper are: (1) the new SCBA framework derived from the maqāṣid Shariah perspective and, (2) the application of this framework in examining the cost effectiveness on the use of drones by the takaful operators especially during disaster.
Smart Cities Landscape and Urban Planning for Sustainability in Brno City
Authors: Fialová Jitka , Bamwesigye Dastan , Łukaszkiewicz Jan , Fortuna-Antoszkiewicz Beata
Published: August 2021

This study aimed to explore the case study of Brno city regarding smart city models. We analyzed Brno considering smart and sustainable city elements, i.e., smart mobility/public transport, smart technology, smart people, smart governance, smart economy, smart living, and smart environment based on transport, energy, and environment referred herein as the smart city and sustainability model. Therefore, we investigated a case study of Brno city in the Czech Republic. We used qualitative techniques such as case study, exploration, observation, and description. We analyzed and comprehended the trends in the various features of smart city and sustainable development of the city of Brno. The findings showed that Brno city is doing its best to maintain smart city models through its governance organs and structures. The city is also working hard to improve some of the aspects that are still lagging. The ongoing developments and the future ones are based on strategic planning for both the short term and long term such as Brno2023, Brno2030, and Brno2050. It was found that Brno has a very well-planned transport system and is integrated with other aspects such as technology, energy, such as the electricity that moves the trolleybuses and trams, and environment. We strongly conclude that even though Brno city still struggles to achieve total sustainability, it is still a model and reflection of a smart and sustainable city. Finally, we noted that Brno city has very good plans and vision the “DNA” of a smart city. However, the implementation still suffers political willingness.
Land Concentration and Land Grabbing Processes—Evidence from Slovakia
Authors: Palšová Lucia , Bandlerová Anna , Machničová Zina
Published: August 2021

In Slovakia, the large-scale acquisition of agricultural land in combination with land concentration represents a legitimate threat that can lead to land grabbing. Based on the research, two interrelated areas of protection need to be effectively regulated to limit land grabbing: the protection of access to land and the protection of agricultural land. Due to the absence of relevant data analysis regarding this issue, the main aim of the study was to analyse the emergence of land concentration in Slovakia based on historical and cultural factors and to evaluate the current legislative and institutional framework of both aspects of land protection with a possible impact on the successively graduating threat of land grabbing. In particular, analytical methods were used, presenting the data from secondary literature sources, a questionnaire survey, and representatives of the Ministry of Agriculture and Rural Development in Slovakia. The research shows that although the state has adopted the necessary legal framework for the protection of property rights to agricultural land, it is not possible to enforce it, as the institutional framework for its implementation is absent. It is also the state’s malfunctioning land protection regulatory mechanism and the absence of indirect action instruments that may be key indicators leading to the processes of industrial agriculture. Therefore, the adoption of legislation limiting agricultural land acquisition is important, but the processes of land grabbing presume the state’s complex provision of a regulatory mechanism and adoption of strategic measures aimed at sustainable land quality and food security.
Evaluating Ocular Response in the Retina and Optic Nerve Head after Single and Fractionated High-Energy Protons
Authors: Mao Xiao-Wen , Stanbouly Seta , Jones Tamako , Nelson Gregory
Published: August 2021

There are serious concerns about possible late radiation damage to ocular tissue from prolonged space radiation exposure, and occupational and medical procedures. This study aimed to investigate the effects of whole-body high-energy proton exposure at a single dose on apoptosis, oxidative stress, and blood-retina barrier (BRB) integrity in the retina and optic nerve head (ONH) region and to compare these radiation-induced effects with those produced by fractionated dose. Six-month-old C57BL/6 male mice were either sham irradiated or received whole-body high energy proton irradiation at an acute single dose of 0.5 Gy or 12 equal dose fractions for a total dose of 0.5 Gy over twenty-five days. At four months following irradiation, mice were euthanized and ocular tissues were collected for histochemical analysis. Significant increases in the number of apoptotic cells were documented in the mouse retinas and ONHs that received proton radiation with a single or fractionated dose (p < 0.05). Immunochemical analysis revealed enhanced immunoreactivity for oxidative biomarker, 4-hydroxynonenal (4-HNE) in the retina and ONH following single or fractionated protons with more pronounced changes observed with a single dose of 0.5 Gy. BRB integrity was also evaluated with biomarkers of aquaporin-4 (AQP-4), a water channel protein, a tight junction (TJ) protein, Zonula occludens-1 (ZO-1), and an adhesion molecule, the platelet endothelial cell adhesion molecule-1 (PECAM-1). A significantly increased expression of AQP-4 was observed in the retina following a single dose exposure compared to controls. There was also a significant increase in the expression of PECAM-1 and a decrease in the expression of ZO-1 in the retina. These changes give a strong indication of disturbance to BRB integrity in the retina. Interestingly, there was very limited immunoreactivity of AQP-4 and ZO-1 seen in the ONH region, pointing to possible lack of BRB properties as previously reported. Our data demonstrated that exposure to proton radiation of 0.5 Gy induced oxidative stress-associated apoptosis in the retina and ONH, and changes in BRB integrity in the retina. Our study also revealed the differences in BRB biomarker distribution between these two regions. In response to radiation insults, the cellular response in the retina and ONH may be differentially regulated in acute or hyperfractionated dose schedules.
Implicit Memory and Anesthesia: A Systematic Review and Meta-Analysis
Authors: Linassi Federico , Obert David Peter , Maran Eleonora , Tellaroli Paola , Kreuzer Matthias , Sanders Robert David , Carron Michele
Published: August 2021

General anesthesia should induce unconsciousness and provide amnesia. Amnesia refers to the absence of explicit and implicit memories. Unlike explicit memory, implicit memory is not consciously recalled, and it can affect behavior/performance at a later time. The impact of general anesthesia in preventing implicit memory formation is not well-established. We performed a systematic review with meta-analysis of studies reporting implicit memory occurrence in adult patients after deep sedation (Observer’s Assessment of Alertness/Sedation of 0–1 with spontaneous breathing) or general anesthesia. We also evaluated the impact of different anesthetic/analgesic regimens and the time point of auditory task delivery on implicit memory formation. The meta-analysis included the estimation of odds ratios (ORs) and 95% confidence intervals (CIs). We included a total of 61 studies with 3906 patients and 119 different cohorts. For 43 cohorts (36.1%), implicit memory events were reported. The American Society of Anesthesiologists (ASA) physical status III–IV was associated with a higher likelihood of implicit memory formation (OR:3.48; 95%CI:1.18–10.25, p < 0.05) than ASA physical status I–II. Further, there was a lower likelihood of implicit memory formation for deep sedation cases, compared to general anesthesia (OR:0.10; 95%CI:0.01–0.76, p < 0.05) and for patients receiving premedication with benzodiazepines compared to not premedicated patients before general anesthesia (OR:0.35; 95%CI:0.13–0.93, p = 0.05).
Calculation of Cement Composition Using a New Model Compared to the Bogue Model
Authors: Shim Sang-Hyo , Lee Tae-Hee , Yang Seong-Joon , Noor Norhazilan Bin Md. , Kim Jang-Ho-Jay
Published: August 2021

The major cement composition ratios of alite, belite, aluminate, and ferrite have been calculated with the Bogue models until now. However, a recent comprehensive analysis based on various experimental data has revealed that the chemical composition of alite, belite, aluminate, and ferrite implemented by the Bogue models are slightly different than the experimental data, where small amounts of Al2O3 and Fe2O3 existing in alite and belite can change the prediction of cement composition. Since the amounts of cement compound are very important factors in determining the properties of concrete, improvement in the calculation would give more precise prediction for application usages such as climate change adaptable cement and high durable concrete manufacturing. For this purpose, 20 new models are proposed by modifying chemical compositions of the cement compounds and verified with the 50 experimental data sets. From the verification, the most accurate models are identified. The calculation using new models exhibit an accuracy improvement of approximately 5% compared to the Bogue models. Their applicable range is also presented. The study results are discussed in detail in the paper.
A Design of Partial Textured Surface on Gear Washers for Reducing Friction and Wear under Low Speed and Heavy Load Conditions
Authors: Liu Yang , Zhang Hui , Dong Guangneng
Published: August 2021

This paper presents the effort to reduce friction and wear of gear washers under low-speed and heavy-load conditions by designing the arrangement of surface textures. The influence of distributional parameters of textures on load-bearing capacity and friction coefficient of gear washers are studied numerically to obtain a preferable surface texturing design. Then, experimental tests were carried out to plot the Stribeck curves of the obtained texture arrangement compared with bare surface and another unoptimizable texture distribution arrangement to facilitate the verification of the simulation results. Theoretical predictions illustrate that the annular gear washers with partial surface texturing provide lower friction coefficients than bare washers. Textures having a sector angle of 20°, a coverage angle of 12°, a circumferential number of 8, and a radial number of 6 are selected as the final optimal surface texture distribution design. Experimental results confirm that the obtained texture arrangement moves the Stribeck curve towards the lower left, indicating thickening of oil film thickness and reduction in friction coefficient. In addition, the weight loss caused by wear is also reduced by the optimized texture design.
Effects of Isothermal Temperature and Soaking Time on Water Quenched Microstructure of Nickel-Based Superalloy GH3536 Semi-Solid Billets
Authors: Xiao Guanfei , Jiang Jufu , Wang Ying , Liu Yingze , Zhang Ying , Tian Yinfeng
Published: August 2021

Semi-solid billets of GH3536 alloy were prepared by semi-solid isothermal treatment of wrought superalloy method. GH3536 samples were soaked at several semi-solid temperatures (1350 °C, 1360 °C, 1364 °C, and 1367 °C) for 5–120 min. The effects of temperature and soaking time on the microstructure of GH3536 billets were studied. The results indicated that the microstructure was affected by coalescence mechanism, Ostwald ripening mechanism, and breaking up mechanism. Semi-solid microstructure of GH3536 alloy was composed of spherical solid particles and liquid phases, and the liquid phases affected the microstructure greatly. At 1350 °C, the coalescence mechanism was dominant at the early stage of isothermal treatment, then the Ostwald ripening mechanism played a major role for the longer soaking times. At higher temperatures, the breaking up mechanism occurred to form large irregular grains and small spherical grains. As the heating continued, the Ostwald ripening mechanism was dominant. However, at 1364 °C and 1367 °C, the solid grains had irregular shapes and large sizes when the isothermal time was 120 min. The optimum parameters for the preparation of GH3536 semi-solid billets were: temperature of 1364–1367 °C and soaking time of 60–90 min.
Internal Forces Analysis of Prestressed Concrete Box Girder Bridge by Using Structural Stressing State Theory
Authors: Liu Shuo , Zhang Yi , Shi Jun , Yang Baisong
Published: August 2021

This paper analyzes the working behavior characteristics of a prestressed concrete transverse large cantilever continuous (PCTLCC) box girder bridge model based on structural stressing state theory and the numerical shape function (NSF) method. At first, the normalized generalized strain energy density (GSED) is established to model the stressing state of the bridge model. Subsequently, the Mann Kendall (M–K) criterion is applied to detect three characteristic loads, respectively, elastic–plastic branch load P (200 kN), failure load Q (300 kN), and progressive failure load H (340 kN), and the failure load Q is found to be the starting load of the damage process of the bridge model, rather than the ultimate load where the structure has been destroyed. Finally, the NSF method is adopted to interpolate the test data, and a detailed analysis for the variation characteristics of the working behavior of the bridge model under loads is performed based on the interpolation results. The characteristic load detection method and experimental data extension method for PCTLCC box girder bridge established in this study can provide valuable references for the design and analysis of such bridges.
Resistive Switching Phenomenon Observed in Self-Assembled Films of Flame-Formed Carbon-TiO2 Nanoparticles
Authors: Commodo Mario , De Falco Gianluigi , Sarnelli Ettore , Campajola Marcello , Aloisio Alberto , D’Anna Andrea , Minutolo Patrizia
Published: August 2021

Nanostructured films of carbon and TiO2 nanoparticles have been produced by means of a simple two-step procedure based on flame synthesis and thermophoretic deposition. At first, a granular carbon film is produced on silicon substrates by the self-assembling of thermophoretically sampled carbon nanoparticles (CNPs) with diameters of the order of 15 nm. Then, the composite film is obtained by the subsequent thermophoretic deposition of smaller TiO2 nanoparticles (diameters of the order of 2.5 nm), which deposit on the surface and intercalate between the carbon grains by diffusion within the pores. A bipolar resistive switching behavior is observed in the composite film of CNP-TiO2. A pinched hysteresis loop is measured with SET and RESET between low resistance and high resistance states occurring for the electric field of 1.35 × 104 V/cm and 1.5 × 104 V/cm, respectively. CNP-TiO2 film produced by flame synthesis is initially in the low resistive state and it does not require an electroforming step. The resistance switching phenomenon is attributed to the formation/rupture of conductive filaments through space charge mechanism in the TiO2 nanoparticles, which facilitate/hinder the electrical conduction between carbon grains. Our findings demonstrate that films made of flame-formed CNP-TiO2 nanoparticles are promising candidates for resistive switching components.
Study on Storage Stability of Activated Reclaimed Rubber Powder Modified Asphalt
Authors: Kong Peipei , Xu Gang , Yang Jingyao , Chen Xianhua , Zhu Yaqin
Published: August 2021

The purpose of this research was to make full use of waste lubricating by-products (LBP) and reclaimed rubber powder (RR) to modify asphalt by a one-pot approach, so as to achieve the dual purpose of solving the poor storage stability of reclaimed rubber powder modified asphalt (RRMA) and the realization of solid waste recycling. A variety of characterization techniques were performed to analyze storage stability, conventional properties and microstructure of LBP-activated reclaimed rubber powder modified asphalt (Blend). Fourier transform infrared spectroscopy illustrated that not only the chemical composition of LBP was very similar to that of asphalt, but also the activation of LBP improved the compatibility of RR with asphalt and enhanced the storage stability of Blend. Fluorescence spectrum and scanning electron microscopy results indicated that the RR without LBP activation was aggregated and dispersed as blocks in asphalt, while the LBP activated RR was uniformly dispersed in the asphalt phase. The segregation test demonstrated that Blend exhibited outstanding storage stability, in which the softening point difference was within 2.5 °C and the segregation rate was −0.2–0.2. In addition, the conventional properties of Blend have been significantly improved, especially in penetration and ductility. More importantly, the short-term aging results demonstrated that, compared with RRMA, Blend possessed excellent anti-aging performance.
Effect of CeO2 Content on Microstructure and Properties of SiCp/Al-Si Composites Prepared by Powder Metallurgy
Authors: Dong Xuedan , Wang Aiqin , Xie Jingpei , Zhu Pengfei
Published: August 2021

The effect of CeO2 content on the microstructure and properties of SiCp/Al-Si composites prepared by powder metallurgy was studied, and the mechanism of CeO2 in composites was deeply analyzed. The results show that the addition of the appropriate amount of CeO2 can refine the Si particles and improve the tensile properties of the SiCp/Al-Si composites. As the CeO2 content increases from 0 to 0.4 vol%, the particle size of the Si phase shows a tendency to decrease first and then increase, while the tensile strength, yield strength, and elongation of the composites show a trend of first increasing and then decreasing. When the CeO2 content is 0.2 vol%, the refining effect of CeO2 and the tensile properties of composites are the best. The fracture mode of SiCp/Al-Si composites with a rare earth addition is a mixed fracture. There are three main mechanisms for CeO2 in SiCp/Al-Si composites. One is when CeO2 serves as the nucleation substrate of Si phase to refine Si particles. The second is when CeO2 reacts with the alloying elements in the aluminum matrix to form a new phase, CeCu2Si2, which can not only play a role of dispersion strengthening, but also improve the bonding strength between Al matrix and Si particles. The third is the pinning effect of CeO2 and CeCu2Si2 particles on grain boundaries or phase boundaries to refine aluminum grains.
Definite Integral Involving Rational Functions of Powers and Exponentials Expressed in Terms of the Lerch Function
Authors: Reynolds Robert , Stauffer Allan
Published: August 2021

This paper gives new integrals related to a class of special functions. This paper also showcases the derivation of definite integrals involving the quotient of functions with powers and the exponential function expressed in terms of the Lerch function and special cases involving fundamental constants. The goal of this paper is to expand upon current tables of definite integrals with the aim of assisting researchers in need of new integral formulae.
Microalgae as Contributors to Produce Biopolymers
Authors: Madadi Rozita , Maljaee Hamid , Serafim Luísa S. , Ventura Sónia P. M.
Published: August 2021

Biopolymers are very favorable materials produced by living organisms, with interesting properties such as biodegradability, renewability, and biocompatibility. Biopolymers have been recently considered to compete with fossil-based polymeric materials, which rase several environmental concerns. Biobased plastics are receiving growing interest for many applications including electronics, medical devices, food packaging, and energy. Biopolymers can be produced from biological sources such as plants, animals, agricultural wastes, and microbes. Studies suggest that microalgae and cyanobacteria are two of the promising sources of polyhydroxyalkanoates (PHAs), cellulose, carbohydrates (particularly starch), and proteins, as the major components of microalgae (and of certain cyanobacteria) for producing bioplastics. This review aims to summarize the potential of microalgal PHAs, polysaccharides, and proteins for bioplastic production. The findings of this review give insight into current knowledge and future direction in microalgal-based bioplastic production considering a circular economy approach. The current review is divided into three main topics, namely (i) the analysis of the main types and properties of bioplastic monomers, blends, and composites; (ii) the cultivation process to optimize the microalgae growth and accumulation of important biobased compounds to produce bioplastics; and (iii) a critical analysis of the future perspectives on the field.
Association between Cone-Beam Computed Tomography and Histological and Immunohistochemical Features in Periapical Lesions Correlated with Thickened Maxillary Sinus Mucosa
Authors: Dumitrescu Alexandra , Martu Maria-Alexandra , Nemtoi Alexandru , Sirghe Ana , Chelaru Liliana , Tatarciuc Diana , Dumitrescu Ana-Maria , Haba Danisia
Published: August 2021

Background and Objectives: Odontogenic sinusitis is a frequently underestimated pathology with fewer symptoms in patients with periapical lesions, periodontal disease, or iatrogenic foreign bodies in the maxillary sinus. The aim of our study was to determine the correlation between maxillary sinusitis and periapical lesions using cone-beam computed tomography (CBCT) imaging and histological and immunohistochemical investigations. Materials and Methods: A total of 1450 initial patients diagnosed with maxillary sinusitis in the Ear-Nose-Throat (ENT) Department, University of Medicine and Pharmacy “Grigore T. Popa” Iasi, Romania, were treated with anti-inflammatory drugs. Of these, 629 still had unresolved symptomatology and were later referred to the Dental Medicine departments for further investigations. Only 50 subjects with periapical lesions in the premolar/molar maxillary area were included in the present study. All the periapical lesions were observed on CBCT and classified using the Periapical Status Index (PSI) and the mean maxillary sinus mucosa thicknesses (MSMT). The enrolled patients underwent surgical procedures with the excision of periapical lesions. The excised samples were submitted to the histological and immunohistochemical investigations. Results: The 50 patients presented periapical lesions of their maxillary teeth in 328 dental units. There was a higher prevalence of periapical lesions in men than in women (chi-square test). We observed a significant difference between the mean MSMT of individuals with periapical lesions compared to those without (p < 0.01). Mean MSMT was 1.23 mm for teeth without periapical lesions and 3.95 mm for teeth with periapical lesions. The histopathological study identified 50% cases with periapical granulomas, 10% cases with periapical granulomas with cystic potential, and 40% cases as periapical cysts. Immunohistochemical stainings showed that CD4+ helper and CD8+ cytotoxic T lymphocytes, along with CD20+ B lymphocytes and CD68+ macrophages, were diffusely distributed in all periapical cysts and in some periapical granulomas, but CD79α+ plasma cells characterized especially periapical granulomas. Conclusions: The current study observed a significant correlation between CBCT maxillary mucosa thickness and type of periapical lesion. Chronic inflammatory lympho-histiocytic infiltrate predominates in periapical lesions, supporting the idea that lesion progression is determined by a humoral-type (CD20+ and CD79α+ B lymphocytes) but also by a cellular-type (CD4+ and CD8+ T lymphocyte population) immune mechanism.
Effects of Zr Content on the Microstructure and Performance of TiMoNbZrx High-Entropy Alloys
Authors: Chen Gengbiao , Xiao Yi , Ji Xixi , Liang Xiubing , Hu Yongle , Cai Zhihai , Liu Jian , Tong Yonggang
Published: August 2021

TiMoNbZrx refractory high-entropy alloys were prepared by vacuum arc melting, and the influence of the Zr alloying element and its content on the phases, microstructure, mechanical properties, and wear resistance of TiMoNbZrx alloys was explored. It was found that the alloys after Zr addition were composed of a single BCC phase. Upon increasing the Zr content, the grain size of the as-cast alloy decreased first and then increased, and TiMoNbZr0.5 exhibited the smallest grain size. Adding an appropriate amount of Zr increased the strength and hardness of the alloys. TiMoNbZr0.5 exhibited the best wear resistance, with a friction coefficient of about 0.33. It also displayed the widest wear scar, the shallowest depth, and the greatest degree of wear on the grinding ball because of the formation of an oxide film during wear.
A Systematic Review of Metabolomic Biomarkers for the Intake of Sugar-Sweetened and Low-Calorie Sweetened Beverages
Authors: Muli Samuel , Goerdten Jantje , Oluwagbemigun Kolade , Floegel Anna , Schmid Matthias , Nöthlings Ute
Published: August 2021

Intake of added sugars (AS) is challenging to assess compared with total dietary sugar because of the lack of reliable assessment methods. The reliance on self-reported dietary data in observational studies is often cited as biased, with evidence of AS intake in relation to health outcomes rated as low to moderate quality. Sugar-sweetened beverages (SSBs) are a major source of AS. A regular and high intake of SSBs is associated with an overall poor diet, weight gain, and cardiometabolic risks. An elevated intake of low-calorie sweetened beverages (LCSBs), often regarded as healthier alternatives to SSBs, is also increasingly associated with increased risk for metabolic dysfunction. In this review, we systematically collate evidence and provide perspectives on the use of metabolomics for the discovery of candidate biomarkers associated with the intake of SSBs and LCSBs. We searched the Medline, Embase, Scopus, and Web of Science databases until the end of December 2020. Seventeen articles fulfilled our inclusion criteria. We evaluated specificity and validity of the identified biomarkers following Guidelines for Biomarker of Food Intake Reviews (BFIRev). We report that the 13C:12C carbon isotope ratio (δ13C), particularly, the δ13C of alanine is the most robust, sensitive, and specific biomarker of SSBs intake. Acesulfame-K, saccharin, sucralose, cyclamate, and steviol glucuronide showed moderate validity for predicting the short-term intake of LCSBs. More evidence is required to evaluate the validity of other panels of metabolites associated with the intake of SSBs.
Uncoupling Thermotolerance and Growth Performance in Chinook Salmon: Blood Biochemistry and Immune Capacity
Authors: Lulijwa Ronald , Young Tim , Symonds Jane E. , Walker Seumas P. , Delorme Natalí J. , Alfaro Andrea C.
Published: August 2021

Ocean warming and extreme sea surface temperature anomalies are threatening wild and domesticated fish stocks in various regions. Understanding mechanisms for thermotolerance and processes associated with divergent growth performance is key to the future success of aquaculture and fisheries management. Herein, we exposed Chinook salmon (Oncorhynchus tshawytscha) to environmentally relevant water temperatures (19–20 °C) approaching their upper physiological limit for three months and sought to identify blood biomarkers associated with thermal stress and resilience. In parallel, blood biochemical associations with growth performance were also investigated. Temperature stress-activated leukocyte apoptosis induced a minor immune response, and influenced blood ion profiles indicative of osmoregulatory perturbation, regardless of how well fish grew. Conversely, fish displaying poor growth performance irrespective of temperature exhibited numerous biomarker shifts including haematology indices, cellular-based enzyme activities, and blood clinical chemistries associated with malnutrition and disturbances in energy metabolism, endocrine functioning, immunocompetence, redox status, and osmoregulation. Findings provide insight into mechanisms of stress tolerance and compromised growth potential. Biochemical phenotypes associated with growth performance and health can potentially be used to improve selective breeding strategies.
Levitation Characteristics Analysis of a Diamagnetically Stabilized Levitation Structure
Authors: Cheng Shuhan , Li Xia , Wang Yongkun , Su Yufeng
Published: August 2021

A diamagnetically stabilized levitation structure is composed of a floating magnet, diamagnetic material, and a lifting magnet. The floating magnet is freely levitated between two diamagnetic plates without any external energy input. In this paper, the levitation characteristics of a floating magnet were firstly studied through simulation. Three different levitation states were found by adjusting the gap between the two diamagnetic plates, namely symmetric monostable levitation, bistable levitation, and asymmetric monostable levitation. Then, according to experimental comparison, it was found that the stability of the symmetric monostable levitation system is better than that of the other two. Lastly, the maximum moving space that allows the symmetric monostable levitation state is investigated by Taguchi method. The key factors affecting the maximum gap were determined as the structure parameters of the floating magnet and the thickness of highly oriented pyrolytic graphite (HOPG) sheets. According to the optimal parameters, work performance was obtained by an experiment with an energy harvester based on the diamagnetic levitation structure. The effective value of voltage is 250.69 mV and the power is 86.8 μW. An LED light is successfully lit on when the output voltage is boosted with a Cockcroft–Walton cascade voltage doubler circuit. This work offers an effective method to choose appropriate parameters for a diamagnetically stabilized levitation structure.
Different Responses of Microbiota across Intestinal Tract to Enterococcus faecium HDRsEf1 and Their Correlation with Inflammation in Weaned Piglets
Authors: Zhou Jin , Luo Ji , Yang Shumin , Xiao Qiling , Wang Xiliang , Zhou Zutao , Xiao Yuncai , Shi Deshi
Published: August 2021

Enterococcus faecium HDRsEf1 (HDRsEf1) was identified to reduce the incidence of diarrhea in weaned piglets, but the mechanism has not been elucidated yet. Based on the fact that gut microbiota plays a crucial role in regulating inflammatory responses, the effects of HDRsEf1 on microbiota across the intestinal tract in weaned piglets were investigated. Microbiota from the luminal contents and the mucosa of the ileum, cecum, and colon of HDRsEf1-treated piglets were explored by 16S rRNA sequencing and qPCR. It was demonstrated that microbiota in different gut niches responded specifically to HDRsEf1, with major alterations occurring in the ileum and cecum. The total bacterial load of microbiota in ileal luminal contents and the relative abundance of Escherichia-Shigella in the ileal mucosa was significantly down-regulated by HDRsEf1 administration, while the relative abundance of butyrate-producing bacteria (including Clostridiaceae-1, Rumencoccidae, and Erysipelotrichaceae) in cecal luminal contents was significantly up-regulated. Moreover, the utilization of HDRsEf1 improved intestinal morphological development and reduced the inflammatory response, which were negatively correlated with the relative abundance of Escherichia-Shigella in the ileal mucosa and butyrate-producing bacteria in cecal luminal contents, respectively. Collectively, this study suggests that the administration of HDRsEf1 alters gut microbiota, thereby alleviating inflammation and improving intestinal morphological development in weaned piglets.
Towards Sustainability Pathway with Bio-Derived Platinum and Palladium Catalyst for Furfural Hydrogenation—A Novel Greener Approach in Catalysis
Authors: Akinbile Babatunde J. , Matsinha Leah C. , Makhubela Banothile C. E. , Ambushe Abayneh A.
Published: August 2021

The use of living plants to recover precious metals with potential catalytic activity is still at the infant stage. In this study, selective hydrogenation of furfural to furfuryl alcohol using novel bio-ore catalysts recovered from the end stage of phytomining process is demonstrated. The phytomining process was carried out in the green house by artificially contaminating cassava (Manihot esculenta) plant with 500 mg/L palladium (Pd) and platinum (Pt) solutions for a period of eight weeks. After harvesting, concentrations of metals as high as 78 ± 0.047 and 1276 ± 0.036 µg/g of Pd and Pt, respectively, were detected in the calcinated root of cassava. The produced bio-ore catalysts; @PdCassCat and @PtCassCat were fully characterized with the following techniques: transmission electron microscopy (TEM), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), powder X-ray diffraction (pXRD), N2-sorption, and UV-visible spectroscopy techniques and directly applied as catalysts for hydrogenation of furfural to furfuryl alcohol. The reaction was conducted under an optimized condition (furfural (10 mmol), triethylamine (Et3N) (10 mmol), formic acid (20 mmol), temperature (160 °C), catalyst amount (40 mg)) realizing a yield of 76.5% and 100% furfuryl alcohol using @PdCassCat and @PtCassCat, respectively. The catalytic activities of the @PdCassCat and @PtCassCat were excellent as well as recyclable up to four and five times, respectively.
Leaching of Ca-Rich Slags Produced from Reductive Smelting of Bauxite Residue with Na2CO3 Solutions for Alumina Extraction: Lab and Pilot Scale Experiments
Authors: Vafeias Michail , Bempelou Amalia , Georgala Eirini , Davris Panagiotis , Balomenos Efthymios , Panias Dimitrios
Published: August 2021

Sustainable utilization of Bauxite Residue (BR) is currently one of the greatest challenges being tackled by the alumina industry, due to its high production rates and limited reuse options. The present work is concerned with the use of BR as a candidate metallurgical raw material for iron (Fe) production and aluminum (Al) extraction. In more detail, at first, BR undergoes reductive smelting to extract its Fe content and produce a slag of mainly calcium aluminate composition. In a second step, Al contained in the calcium aluminate phases is extracted hydrometallurgically by leaching with a Na2CO3 aqueous solution. The focus of the current study is the optimization of this leaching process, and it was performed in two stages. The first was a laboratory scale investigation on the main parameters affecting the extraction rate of Al. The second stage was performed in pilot scale and incorporated observations and suggestions based on the laboratory scale investigation. Laboratory work showed that more than 50% of aluminum could be easily extracted in less than 1 h, in 5% S/L, at 70 °C and with an 20% excess of Na2CO3. Pilot scale work, by successfully applying the suggestions derived from laboratory scale work, achieved an average Al extraction of 68% from a 10% S/L pulp, with a slag of optimized composition in relation to the one used in the laboratory scale.