bluuebunny/crossref_metadata_2025 huggingface dataset:
Electron Beam Powder Bed Fusion of Water Atomized Iron and Powder Blends
Authors: Kirchner Alexander , Klöden Burghardt , Franke-Jurisch Marie , Walther Gunnar , Weißgärber Thomas
Published: February 2022

In the present state of the art, highly spherical alloy powders are employed as feedstock in powder bed fusion processes. These powders are characterized by high flowability and apparent density. Their elaborate fabrication process is reflected in high powder price, adding a significant fraction to the cost of additively manufactured parts. Thus, the use of non-spherical powders, such as water atomized material, can lower costs significantly. Here, the electron beam powder bed fusion (PBF-EB) of standard water atomized iron powder used for press-and-sinter is studied. Despite raking problems, using the coating mechanism in standard configuration samples with densities exceeding 99% were fabricated. In a further step, the addition of alloying elements by powder blending is explored. Important powder properties of feedstock blended from irregular and spherical powders are characterized. The PBF-EB processing of two alloys is presented. The first represents a low carbon steel. Samples were characterized by metallographic cross-section, energy dispersive X-ray (EDX) mapping, and mechanical testing. The second alloy system is a FeCrAl. After PBF-EB processing of the powder mixture, chemical homogeneity was achieved. Besides the low cost, this approach of using water atomized powder mixed with master alloy offers the advantage of high flexibility for potential application.
Study on the Magnetocaloric Effect of Room Temperature Magnetic Refrigerant Material La0.5Pr0.5(Fe1−xCox)11.4Si1.6 and the Effect Arising from Co Doping on Its Curie Temperature
Authors: Shang Tao , Zheng Lin , Zhao Jianjun , Li Guodong , Wu Ruixia
Published: February 2022

The arc-melting method was adopted to prepare the compound La0.5Pr0.5(Fe1−xCox)11.4Si1.6 (x = 0, 0.02, 0.04, 0.06, 0.08), and the magnetocaloric effect of the compound was investigated. As indicated by the powder X-ray diffraction (XRD) results, after receiving 7-day high temperature annealing at 1373 K, all the compounds formed a single-phase cubic NaZn13 crystal structure. As indicated by the magnetic measurement, the most significant magnetic entropy change |∆SM(T)| of the sample decreased from 28.92 J/kg·K to 4.22 J/kg·K with the increase of the Co content under the 0–1.5 T magnetic field, while the Curie temperature TC increased from 185 K to the room temperature 296 K, which indicated that this series of alloys are the room temperature magnetic refrigerant material with practical value. By using the ferromagnetic Curie temperature theory and analyzing the effect of Co doping on the exchange integral of these alloys, the mechanism that the Curie temperature of La0.5Pr0.5(Fe1−xCox)11.4Si1.6 and La0.8Ce0.2(Fe1−xCox)11.4Si1.6 increased with the increase in the Co content was reasonably explained. Accordingly, this paper can provide a theoretical reference for subsequent studies.
The Effect of Trace Oxygen Addition on the Interface Behavior of Low-Alloy Steel
Authors: Novák Vlastimil , Řeháčková Lenka , Váňová Petra , Sniegoň Michal , Matýsek Dalibor , Konečná Kateřina , Smetana Bedřich , Rosypalová Silvie , Tkadlečková Markéta , Drozdová Ľubomíra , Klus Petr
Published: February 2022

This work aims to assess the effect of an oxygen content graded in minimal quantities, on the order of hundreds of ppms, on the determination of surface tension of low-alloy FeCOCr and FeCONi steels in contact with a corundum substrate. Oxygen, as a surface-active element, was segregated at the surface where it interacted with the major components of the alloys, leading to a reduction in surface tension. The sessile drop method was used for wetting tests in the temperature range from steel liquidus temperatures to 1600 °C under nonoxidizing conditions. The effect of oxygen on surface tension and wetting angles was verified by statistical analysis using the Kruskal–Wallis test, which supported the results stating that the values of these quantities decreased with increasing oxygen content. Furthermore, liquidus temperatures, which are of practical importance, were determined by the optical and DTA methods and then compared with theoretically calculated temperature values. It turned out that the increased chromium content causes difficulties in determining surface tension up to 1550 °C due to the formation of a thin Cr2O3 layer. In addition, SEM and XRD analyses accompanied by calculations in the FactSage oxide database were performed to better understand the wetting mechanism.
Application of a Robust Decision-Making Rule for Comprehensive Assessment of Laser Cutting Conditions and Performance
Authors: Madić Miloš , Petrović Goran , Petković Dušan , Antucheviciene Jurgita , Marinković Dragan
Published: February 2022

Laser cutting parameters synergistically affect, although in different quantitative and qualitative manners, multiple process performances, such as the resulting cut quality characteristics, material removal rate, cutting time, and costs, and the determination of the most appropriate laser cutting conditions for a given application is of prime importance. Given the existence of multiple mutually opposite performances, assessment and laser cutting conditions and performance can be considered a multiple-criteria decision-making (MCDM) problem. In order to overcome the possible inconsistency of rankings determined by different MCDM methods while solving the same decision-making problem, the present study promotes a novel methodology for the assessment and selection of laser cutting conditions by developing a robust decision-making rule (RDMR) that combines different decision-making rules from six MCDM methods and Taguchi’s principles of robust design. In order to illustrate the application of the proposed methodology, CO2 laser cutting in a stainless-steel experiment, based on the use of the Box–Behnken design, was conducted. On the basis of the experimental results, a comprehensive laser cutting MCDM model was developed with seven criteria related to cut quality (i.e., kerf geometry and cut surface), productivity, variable costs, and environmental aspects. It was observed that there was no laser cutting condition that could be considered as the best regime with respect to the different laser cutting process performances. Kendall’s and Spearman’s rank correlation coefficients indicated a certain level of disagreement among the resulting rankings of the laser cutting conditions produced by the considered MCDM methods, whereas the application of the proposed RDMR ensured the highest level of ranking consistency. Some possibilities for modeling of RDMR and its further use for the assessment of arbitrarily chosen laser cutting conditions and the use of the derived model to perform sensitivity analysis for determining the most influential laser cutting parameters are also discussed and addressed. It was observed that laser cutting parameters in different laser cutting conditions may have a variable effect on the resulting overall process performances. The comparison of the obtained results and the results determined by classical desirability-based multi-objective optimization revealed that there exists substantial agreement between the most preferable and least preferable laser cutting conditions, thus justifying the applied methodology.
Predicting the Electrical Impedance of Rolling Bearings Using Machine Learning Methods
Authors: Kirchner Eckhard , Bienefeld Christoph , Schirra Tobias , Moltschanov Alexander
Published: February 2022

The present paper describes a measurement setup and a related prediction of the electrical impedance of rolling bearings using machine learning algorithms. The impedance of the rolling bearing is expected to be key in determining the state of health of the bearing, which is an essential component in almost all machines. In previous publications, the determination of the impedance of rolling bearings has already been advanced using analytical methods. Despite the improvements in accuracy achieved within the calculations, there are still discrepancies between the calculated and the measured impedance, leading to an approximately constant off-set value. This discrepancy motivates the machine learning approach introduced in this paper. It is shown that with the help of the data-driven methods the difference between analytical prediction and measurement is reduced to the order of up to 2% across the operational range analyzed so far. To introduce the context of the research shown, first the underlying physics of bearing impedance is presented. Subsequently different machine learning approaches are highlighted and compared with each other in terms of their prediction quality in the results part of this paper. As a further aspect, in addition to the prediction of the bearing impedance, it is investigated whether the rotational speed present at the bearing can be predicted from the frequency spectrum of the impedance using order analysis methods which is independent from the force prediction accuracy. The background to this is that, if the prediction quality is sufficiently high, the additional use of speed sensors could be omitted in future investigations.
3D Reconstruction of High Reflective Welding Surface Based on Binocular Structured Light Stereo Vision
Authors: Li Baizhen , Xu Zhijie , Gao Feng , Cao Yanlong , Dong Quancheng
Published: February 2022

The inspection of welding surface quality is an important task for welding work. With the development of product quality inspection technology, automated and machine vision-based inspection have been applied to more industrial application fields because of its non-contact, convenience, and high efficiency. However, challenging material and optical phenomena such as high reflective surface areas often present on welding seams tend to produce artifacts such as holes in the reconstructed model using current visual sensors, hence leading to insufficiency or even errors in the inspection result. This paper presents a 3D reconstruction technique for highly reflective welding surfaces based on binocular style structured light stereo vision. The method starts from capturing a fully lit image for identifying highly reflective regions on a welding surface using conventional computer vision models, including gray-scale, binarization, dilation, and erosion. Then, fringe projection profilometry is used to generate point clouds on the interested area. The mapping and alignment from 2D image to 3D point cloud is then established to highlight features that are vital for eliminating “holes”—large featureless areas—caused by high reflections such as the specular mirroring effect. A two-way slicing method is proposed to operate on the refined point cloud, following the concept of dimensionality reduction to project the sliced point cloud onto different image planes before a Smoothing Spline model is applied to fit the discrete point formed by projection. The 3D coordinate values of points in the “hole” region are estimated according to the fitted curves and appended to the original point cloud using iterative algorithms. Experiment results verify that the proposed method can accurately reconstruct a wide range of welding surfaces with significantly improved precision.
Objective Criticism and Negative Conclusions on Using the Fuzzy SWARA Method in Multi-Criteria Decision Making
Authors: Stević Željko , Das Dillip Kumar , Tešić Rade , Vidas Marijo , Vojinović Dragan
Published: February 2022

The quality of output or decision-making depends on high-quality input data, their adequate evaluation, the application of adequate approaches, and accurate calculation. In this paper, an objective criticism of applying the fuzzy SWARA (step-wise weight assessment ratio analysis) method based on the Chang TFN (triangular fuzzy number) scale is performed. Through research, it has been noticed that a large number of studies use this approach and, as an epilogue, there are wrong decisions based on inconsistent values in relation to the initial assessment of decision-makers (DMs). Seven representative studies (logistics, construction industry, financial performance management, and supply chain) with different parameter structures and decision matrix sizes have been singled out. The main hypothesis has been set, which implies that the application of this approach leads to wrong decisions because the weight values of the criteria are incorrect. A comparative analysis with the improved fuzzy SWARA (IMF SWARA) method has been created and a number of negative conclusions has been reached on using the fuzzy SWARA method and the Chang scale: Primarily, that using such an approach is impossible for two or more criteria to have equal value, that allocating TFN (1,1,1) leads to criteria values that are inconsistent with expert evaluation, that the last-ranked criteria in the fuzzy SWARA method have no influential value on the ranking of alternatives, that there is a great gap between the most significant and last-ranked criteria, and that the most significant criterion has a huge impact on the evaluation of alternative solutions and decision making. As a general conclusion, it is given that this approach is not adequate for application in problems of multi-criteria decision making because it produces inadequate management of processes and activities in various spheres.
Incorporating Phrases in Latent Query Reformulation for Multi-Hop Question Answering
Authors: Tang Jiuyang , Hu Shengze , Chen Ziyang , Xu Hao , Tan Zhen
Published: February 2022

In multi-hop question answering (MH-QA), the machine needs to infer the answer to a given question from multiple documents. Existing models usually apply entities as basic units in the reasoning path. Then they use relevant entities (in the same sentence or document) to expand the path and update the information of these entities to finish the QA. The process might add an entity irrelevant to the answer to the graph and then lead to incorrect predictions. It is further observed that state-of-the-art methods are susceptible to reasoning chains that pivot on compound entities. To make up the deficiency, we present a viable solution, i.e., incorporate phrases in the latent query reformulation method (IP-LQR), which incorporates phrases in the latent query reformulation to improve the cognitive ability of the proposed method for multi-hop question answering. Specifically, IP-LQR utilizes information from relevant contexts to reformulate the question in the semantic space. Then the updated query representations interact with contexts within which the answer is hidden. We also design a semantic-augmented fusion method based on the phrase graph, which is then used to propagate the information. IP-LQR is empirically evaluated on a popular MH-QA benchmark, HotpotQA, and the results of IP-LQR consistently outperform those of the state of the art, verifying its superiority. In summary, by incorporating phrases in the latent query reformulation and employing semantic-augmented embedding fusion, our proposed model can lead to better performance on MH-QA.
Modelling Deprivation Level and Multimorbidity in a Health District
Authors: Botija Yagüe María Pilar , Sorbet-Santiago Sofía , Díaz-Carnicero Javier , González-de-Julián Silvia , Usó-Talamantes Ruth
Published: February 2022

Deprivation is associated with an increased risk of developing chronic health conditions and with worse outcomes in multimorbidity. The goal of our study was to develop an integrated population index of deprivation (IPID) to observe the influence of deprivation on morbidity and the subsequent use of healthcare resources in one health district, using the socioeconomic, clinical and geographical data from its administrative health records. Eight socioeconomic indicators were identified and weighted using the methodology of two-phase principal component analysis, providing an index that allowed each census section to be classified into seven deprivation groups. Secondly, the possible relation between the IPID and the variables for multimorbidity and healthcare resources was analysed using the theory of multiple comparisons. It was observed that places with a greater proportion of healthy people presented lower values of deprivation and that, at lower levels of deprivation, there were fewer hospital admissions. The results show that living in an area with a higher deprivation index is associated with greater consumption of healthcare resources and disease burden. Identifying areas of sociosanitary vulnerability can help to identify health inequalities and allow intervention by clinical practices and healthcare management to reduce them.
Analysis of Solutions, Asymptotic and Exact Profiles to an Eyring–Powell Fluid Modell
Authors: Díaz José Luis , Rahman Saeed Ur , Sánchez Rodríguez Juan Carlos , Simón Rodríguez María Antonia , Filippone Capllonch Guillermo , Herrero Hernández Antonio
Published: February 2022

The aim of this article was to provide analytical and numerical approaches to a one-dimensional Eyring–Powell flow. First of all, the regularity, existence, and uniqueness of the solutions were explored making use of a variational weak formulation. Then, the Eyring–Powell equation was transformed into the travelling wave domain, where analytical solutions were obtained supported by the geometric perturbation theory. Such analytical solutions were validated with a numerical exercise. The main finding reported is the existence of a particular travelling wave speed a=1.212 for which the analytical solution is close to the actual numerical solution with an accumulative error of <10−3.
A Comprehensive Review of the Technological Solutions to Analyse the Effects of Pandemic Outbreak on Human Lives
Authors: Shah Ishwa , Doshi Chelsy , Patel Mohil , Tanwar Sudeep , Hong Wei-Chiang , Sharma Ravi
Published: February 2022

A coronavirus outbreak caused by a novel virus known as SARS-CoV-2 originated towards the latter half of 2019. COVID-19’s abrupt emergence and unchecked global expansion highlight the inability of the current healthcare services to respond to public health emergencies promptly. This paper reviews the different aspects of human life comprehensively affected by COVID-19. It then discusses various tools and technologies from the leading domains and their integration into people’s lives to overcome issues resulting from pandemics. This paper further focuses on providing a detailed review of existing and probable Artificial Intelligence (AI), Internet of Things (IoT), Augmented Reality (AR), Virtual Reality (VR), and Blockchain-based solutions. The COVID-19 pandemic brings several challenges from the viewpoint of the nation’s healthcare, security, privacy, and economy. AI offers different predictive services and intelligent strategies for detecting coronavirus signs, promoting drug development, remote healthcare, classifying fake news detection, and security attacks. The incorporation of AI in the COVID-19 outbreak brings robust and reliable solutions to enhance the healthcare systems, increases user’s life expectancy, and boosts the nation’s economy. Furthermore, AR/VR helps in distance learning, factory automation, and setting up an environment of work from home. Blockchain helps in protecting consumer’s privacy, and securing the medical supply chain operations. IoT is helpful in remote patient monitoring, distant sanitising via drones, managing social distancing (using IoT cameras), and many more in combating the pandemic. This study covers an up-to-date analysis on the use of blockchain technology, AI, AR/VR, and IoT for combating COVID-19 pandemic considering various applications. These technologies provide new emerging initiatives and use cases to deal with the COVID-19 pandemic. Finally, we discuss challenges and potential research paths that will promote further research into future pandemic outbreaks.
The Impact of Preoperative Risk Factors on Peritoneal Dialysis-Related Peritonitis: A Single-Center Prospective Study in Japan
Authors: Sato Toshihiro , Anan Go , Hirose Takuo , Tajima Ryo , Hoshino Kento , Miyake Yuka , Fukunaga Tsugumi , Kato Toshiko , Endo Akari , Ito Hiroki , Nakayama Shingo , Hashimoto Hideaki , Ishiyama Katsuya , Kimura Tomoyoshi , Mori Takefumi
Published: February 2022

Background and Objectives: Peritoneal dialysis (PD)-related peritonitis is a critical problem. However, preoperative risk factors for PD-related peritonitis have not been established. Thus, we aimed to determine the preoperative risk factors for PD-related peritonitis. Materials and Methods: This is a single-center prospective observational study. All peritonitis episodes during the study period were recorded, and preoperative and intraoperative clinical parameters were compared between patients with and without peritonitis to examine risk factors for PD-related peritonitis. Furthermore, subcutaneous and abdominal fat volumes were evaluated using computed tomography. Results: Among a total of 118 patients, 24 patients developed peritonitis. The proportion of male patients (83% vs. 61%, p = 0.04), body mass index (25 vs. 22 kg/m2, p = 0.04), and subcutaneous fat area (120 vs. 102 cm2, p = 0.01) were significantly higher and the proportion of patients living with family members (75% vs. 94%, p = 0.02) was significantly lower in the peritonitis group than in the non-peritonitis group. There were no significant differences in age, operation method, surgeon experience, previous abdominal surgery, medical history of diabetic nephropathy, serum albumin level, and renal function between the two groups. Conclusions: Male patients with high subcutaneous fat who are living alone might be at higher risk of PD-related peritonitis. These characteristics might be useful in risk assessment and patient education before PD induction.
Muscle Quality of Knee Extensors Based on Several Types of Force in Multiple Sclerosis Patients with Varying Degrees of Disability
Authors: Portilla-Cueto Kora , Medina-Pérez Carlos , Romero-Pérez Ena Monserrat , Núñez-Othón Gabriel , Horta-Gim Mario A. , de Paz José Antonio
Published: February 2022

Background and Objectives: Multiple sclerosis (MS) tends to affect muscle performance, mainly in the lower extremities. The degree of disability is associated with the loss of strength and muscle mass, to varying extents. Muscle quality (MQ) expresses the amount of force produced relative to the activated muscle mass. The purpose of this study was to compare the MQ of the knee extensors in the main manifestations of strength (isometric, dynamic strength, and power) among patients with differing degrees of neurological disability and evolutionary forms of the disease. We also establish reference values for MQ in MS patients (pwMS). Materials and Methods: In total, 250 pwMS were evaluated according to the Expanded Disability Status Scale (EDSS). The maximum dynamic and isometric forces and muscle power manifested a load of 60% of the maximum dynamics of the knee extensors. The lean mass of the thigh and hip was determined by densitometry, and the MQ was calculated for the three types of force evaluated. Results: The pwMS with relapsing remitting MS (RRMS) presented isometric MQ values that were 15.8% better than those of pwMS with primary progressive MS (PPMS) and 13.8% better than those of pwMS with secondary progressive MS (SPMS). For pwMS with SPMS, the dynamic MQ was 16.7% worse than that of patients with RRMS, while the power MQ was 29.5% worse. By degree of disability (<4 >7.5 EDSS score), patients with better MQ had mild EDSS scores, and patients with severe EDSS scores had 24.8%, 25.9%, and 40.3% worse isometric, dynamic, and power MQ scores, respectively, than those with RRMS. Based on these results, reference values for MQ in pwMS were established. Conclusions: The pwMS with different types of MS do not show differences in lean mass or strength but do show differences in MQ. In pwMS with different EDSS grades, there are no differences in lean mass, but there are differences in strength based on MQ, especially power MQ.
Tinnitus Associated with Mild Osteomyelitis of the Temporal Bone Reversed after Conservative Antibiotic Treatment: A Case Series
Authors: Tseng Ping-Tao , Chen Tien-Yu , Lui Chun-Chung , Chen Yen-Wen , Chen Jiann-Jy
Published: February 2022

The symptomatology and diagnostic tools for osteomyelitis of the temporal bone have not been well documented. Diagnosis of early stage (i.e., mild form) osteomyelitis of the temporal bone may be delayed due to the limitations of traditional computed tomography’s (CT) imaging resolution. With the advancement of high-resolution CT (HRCT) images, clinicians can now observe images that could not be observed with traditional CT imaging. In this neuro-image report, we present three patients with refractory/untreatable tinnitus. In their HRCT images, mild osteomyelitis of the temporal bone was revealed by mucosa thickening with bony sequestration of air cells, mild opacification of the air cells, and soft tissue density in the middle ear cavity, mild opacification, and bony sequestration attributed to mucosa thickening of the mastoid air cells (along with the cortical bone). All of the clinical presentations and findings in the pure tone audiometry of the reported patients improved after adequate antibiotic treatment. The current report highlights the potential benefit of HRCT to diagnose this in such patients. In addition, immediate and conservative antibiotic treatment is recommended for managing these patients shortly after the detection of mild osteomyelitis of the temporal bone. This treatment could reduce the risk of progression to the severe form.
The Role of Diffusion Weighted MR Imaging in the Diagnosis of Tendon Injuries of the Ankle and Foot
Authors: Aydın Hasan , Kızılgöz Volkan , Ersan Önder , Hekimoğlu Baki
Published: February 2022

Background and objectives: Our aim is to determine the diagnostic performance and utility of Diffusion Weighted MR Imaging (DWI) against the routine Magnetic Resonance Imaging (MRI) for the evaluation of patients with tendon injuries of the ankle and foot. Materials and Method: After institutional review board approval and informed consent taken from all the patients, ankle and foot MR imaging and DWI-Apparent Diffusion Coefficient (ADC) mapping were performed on the 81 injured tendons of 50 patients. All tendon injuries were named as Rupture (R), Partial tear (PT), and Tenosynovitis (T). Diagnostic interpretation was based on the MRI-DWI and ADC mapping, verified by either open surgery, diagnostic arthroscopy, or conservative procedures-splint application. Statistical analysis of this research was assessed by Fischer’s exact test, variance analysis test between dependent groups, Receiver Operating Characteristics (ROC) curve, and Pearson chi square statistics. Results: MRI depicted all tendon injuries with 70% sensitivity and 100% specificity, and showed a significant statistical relationship to surgical and arthroscopic references with high agreement (p < 0.05, k: 0.609). DWI had 100% sensitivity and 83–90% specificity for the visualization of tendon injuries with certain agreement and a significant statistical relationship to the gold standard (p < 0.05, k: 0.890–0.899). For all those injured tendons, DWI had 100% sensitivity for the diagnosis of R, and 92–97% sensitivity corresponding to PT and T over routine ankle MR imaging. The specificity of DWI to MRI ranged from 75 to 44% for all the injured tendons. DWI had significant statistical superiority over MRI for the visualization of R, PT, and T of all tendons included in this research (p < 0.05). Conclusions: DWI is a good imaging modality for the visualization of ankles with tendon injuries, possibly further improving the sensitivity of the classical ankle and foot MRI, and supplying more beneficial and diagnostic information than routine MR imaging on the basis of R, PT, and T of tendons at the ankle and foot.
Experimental Study and Mathematical Modeling of a Nanofiltration Membrane System for the Recovery of Polyphenols from Wine Lees
Authors: López-Borrell Alexis , López-Pérez María-Fernanda , Cardona Salvador Cayetano , Lora-García Jaime
Published: February 2022

The winemaking process in Spain generates a significant amount of wastes such as wine lees. Currently, the nanofiltration process is a viable technique for the revalorization of compounds from wastes. In this aspect, this technique can be used for the recovery of compounds, such as polyphenols, as well as active principles widely used in industries, such as pharmaceuticals or cosmetics. Polyphenols are found in acceptable amounts in wine lees wastes and it is interesting to study the nanofiltration process viability to recover them. In order to study this possibility, it is necessary to determine the choice of the best membrane to use and the effect of operational parameters such as pressure, temperature, cross-flow rates, and concentration. In addition, it is important to be able to develop a mathematical model that can help in the future design of lees treatment plants. The treatment of red wine lees to concentrate polyphenols has been studied in a laboratory plant using different membranes (RO and NF) at different pressures (4.5, 9.5, and 14.5 bar), different temperatures (293, 303, and 308 K), and two concentrations (2100 and 1100 mg tyrosol eq·L−1). The results have been encouraging to consider nanofiltration as a viable technique for the treatment and revalorization of this waste. The most suitable membrane has been the NF270, in which 96% rejection rates have been obtained, with a flux of 30 L·h−1·m−2. Moreover, in this study, the Spiegler–Kedem model (SKM) was used to calculate mass transfer constants and permeabilities. Suitable adjustments of these parameters were obtained to validate this mathematical model. For this reason, the SKM might be used in future studies to continue in the research work of the treatment of wine lees wastes.
Fabrication of High Surface Area Microporous ZnO from ZnO/Carbon Sacrificial Composite Monolith Template
Authors: Mondal Kunal , Islam Monsur , Singh Srujan , Sharma Ashutosh
Published: February 2022

Fabrication of porous materials from the standard sacrificial template method allows metal oxide nanostructures to be produced and have several applications in energy, filtration and constructing sensing devices. However, the low surface area of these nanostructures is a significant drawback for most applications. Here, we report the synthesis of ZnO/carbon composite monoliths in which carbon is used as a sacrificial template to produce zinc oxide (ZnO) porous nanostructures with a high specific surface area. The synthesized porous oxides of ZnO with a specific surface area of 78 m2/g are at least one order of magnitude higher than that of the ZnO nanotubes reported in the literature. The crucial point to achieving this remarkable result was the usage of a novel ZnO/carbon template where the carbon template was removed by simple heating in the air. As a high surface area porous nanostructured ZnO, these synthesized materials can be useful in various applications including catalysis, photocatalysis, separation, sensing, solar energy harvest and Zn-ion battery and as supercapacitors for energy storage.
A Parallel Tracking of Salivary and Gut Microbiota Profiles Can Reveal Maturation and Interplay of Early Life Microbial Communities in Healthy Infants
Authors: Reddel Sofia , Pascucci Giuseppe Rubens , Foligno Silvia , Del Chierico Federica , Vernocchi Pamela , Marzullo Alessandra , Pattumelli Maria Grazia , Palma Paolo , Salvatori Guglielmo , Putignani Lorenza
Published: February 2022

In this study, the onset and shaping of the salivary and gut microbiota in healthy newborns during the first period of life has been followed, evaluating the impact of salivary microbiota on the development of early fecal microbial communities. The microbiota of 80 salivary and 82 fecal samples that were collected from healthy newborns in the first six months of life, was investigated by 16S rRNA amplicon profiling. The microbial relationship within and between the saliva and gut ecosystems was determined by correlation heatmaps and co-occurrence networks. Streptococcus and Staphylococcus appeared as early commensals in the salivary microbiota, dominating this ecosystem through the time, while Fusobacterium, Prevotella, Porphyromonas, Granulicatella, and Veillonella were late colonizers. Enterobacteriaceae, Staphylococcus and Streptococcus were gut pioneers, followed by the anaerobic Bifidobacterium, Veillonella, Eggerthella, and Bacteroides. Streptococcus, Staphylococcus, and Veillonella were shared by the gut and saliva ecosystems. The saliva and gut microbiota seem to evolve independently, driven by local adaptation strategies, except for the oral Streptococcus and Veillonella that are involved in gut microbiota development as seeding species. This study offers a piece of knowledge on how the oral microbiota may affect the gut microbiota in healthy newborns, shedding light onto new microbial targets for the development of therapies for early life intestinal dysbiosis.
The Combination of In Vitro Assessment of Stress Tolerance Ability, Autoaggregation, and Vitamin B-Producing Ability for New Probiotic Strain Introduction
Authors: Khromova Natalya Yu. , Epishkina Julia M. , Karetkin Boris A. , Khabibulina Natalia V. , Beloded Andrey V. , Shakir Irina V. , Panfilov Victor I.
Published: February 2022

The health benefits of probiotics are beyond doubt. The positive effects of lactobacilli and bifidobacteria on the function of many body systems have been repeatedly proven by various studies. To completely realize the potential of probiotic microorganisms, the strains should be tested by the greatest combination of characteristics that contribute to the wellness of the host. In this work, for the first time, a combined assessment of the probiotic properties and vitamin B-producing potential of various species and strains of bifidobacteria and lactobacilli was carried out. The presence of an additional advantage, such as vitamin-producing ability, can prevent vitamin deficiency both at the level of the consumption of fermented foods, when the enrichment will occur naturally on the spot, and during colonization by these intestinal strains, when synthesis will occur in vivo. To select potential probiotics, the stress tolerance ability of 16 lactic acid bacteria and bifidobacteria strains to low pH values, bile, and proteolytic enzymes, as well as their ability to autoaggregate, were studied under conditions of modeling the gastrointestinal tract in vitro. The ability of the strains to extracellularly accumulate water-soluble B vitamins was evaluated by capillary electrophoresis. Among the tested strains of bifidobacteria, B. adolescentis VKPM AC-1662 is of interest; it was characterized by the greatest stress tolerance ability and the ability to autoaggregate, in addition to the extracellular synthesis of riboflavin and pyridoxine. Among lactic acid bacteria, L. sakei VKPM B-8936 demonstrated the greatest tolerance to low pH, L. plantarum VKPM B–11007 to duodenal conditions, L. acidophilus VKPM B-2213 to pepsin, and L. salivarius VKPM B–2214 to pancreatin. The highest percentage of autoaggregation was observed in L. salivarius VKPM B-2214, which also accumulated the largest amount of pantothenic acid, but it was sensitive to stress conditions. The obtained results could be used to create new products enriched with probiotics and B vitamins.
Basic Evaluation of Phase Relation in a Phosphorus-Containing System Saturated with CaSiO3 at Elevated Temperatures for the Utilization of Steelmaking Slag and Sewage Sludge as Phosphorus Resources
Authors: Uchida Yu-ichi , Watanabe Chiho , Tsuruoka Hideki
Published: February 2022

In view of obtaining fundamental information on phosphorus recovery from steelmaking slag and sewage sludge, a laboratory experiment using the model specimen of a slag/sludge mixture prepared at 1573 K was carried out to investigate phase relation in a [CaO-SiO2-P2O5]-based system. The triangular compositional region, comprising of apices CaO·SiO2 (CS), 3CaO·P2O5 (C3P), and 2CaO·SiO2-3CaO·P2O5 solid solution (C2S-C3Pss), was considered with particular interest. In this region, using SEM-EDX observation it was found that solid saturated CS and the solid C2S-C3Pss with a relatively high phosphorus content can coexist. With the addition of Al2O3 or Fe2O3 to the same specimens, the liquidus phase appeared as a third phase; however, CS and C2S-C3Pss phases were still observed for up to 5mass% addition. The further addition of Al2O3 or Fe2O3 to 10mass% resulted in dissolution of the solid CS phase, although C2S-C3Pss remained as the phosphorus concentrated phase. These results show that phase equilibria based on the ternary system would be stable and be beneficial for phosphorus recovery.
Spectral Angle Mapping and AI Methods Applied in Automatic Identification of Placer Deposit Magnetite Using Multispectral Camera Mounted on UAV
Authors: Sinaice Brian Bino , Owada Narihiro , Ikeda Hajime , Toriya Hisatoshi , Bagai Zibisani , Shemang Elisha , Adachi Tsuyoshi , Kawamura Youhei
Published: February 2022

The use of drones in mining environments is one way in which data pertaining to the state of a site in various industries can be remotely collected. This paper proposes a combined system that employs a 6-bands multispectral image capturing camera mounted on an Unmanned Aerial Vehicle (UAV) drone, Spectral Angle Mapping (SAM), as well as Artificial Intelligence (AI). Depth possessing multispectral data were captured at different flight elevations. This was in an attempt to find the best elevation where remote identification of magnetite iron sands via the UAV drone specialized in collecting spectral information at a minimum accuracy of +/− 16 nm was possible. Data were analyzed via SAM to deduce the cosine similarity thresholds at each elevation. Using these thresholds, AI algorithms specialized in classifying imagery data were trained and tested to find the best performing model at classifying magnetite iron sand. Considering the post flight logs, the spatial area coverage of 338 m2, a global classification accuracy of 99.7%, as well the per-class precision of 99.4%, the 20 m flight elevation outputs presented the best performance ratios overall. Thus, the positive outputs of this study suggest viability in a variety of mining and mineral engineering practices.
Synthesis of Polyanionic Cellulose Carbamates by Homogeneous Aminolysis in an Ionic Liquid/DMF Medium
Authors: Bui Cuong Viet , Rosenau Thomas , Hettegger Hubert
Published: February 2022

Polyanionic cellulose carbamates were synthesized by rapid and efficient homogeneous aminolysis of cellulose carbonate half-esters in an ionic liquid/DMF medium. Cellulose bis-2,3-O-(3,5-dimethylphenyl carbamate), as a model compound, reacted with different chloroformates to cellulose carbonates. These intermediates were subjected to aminolysis, for which both the reactivity of different chloroformates towards C6-OH and the reactivity/suitability of the respective carbonate half-ester in the aminolysis were comprehensively studied. Phenyl chloroformate and 4-chlorophenyl chloroformate readily reacted with C6-OH of the model cellulose derivative, while 4-nitrophenyl chloroformate did not. The intermediate 4-chlorophenyl carbonate derivative with the highest DS (1.05) was then used to evaluate different aminolysis pathways, applying three different amines (propargyl amine, β-alanine, and taurine) as reactants. The latter two zwitterionic compounds are only sparingly soluble in pure DMF as the typical reaction medium for aminolysis; therefore, several alternative procedures were suggested, carefully evaluated, and critically compared. Solubility problems with β-alanine and taurine were overcome by the binary solvent system DMF/[EMIM]OAc (1:1, v/v), which was shown to be a promising medium for rapid and efficient homogeneous aminolysis and for the preparation of the corresponding cellulose carbamate derivatives or other compounds that are not accessible by conventional isocyanate chemistry. The zwitterionic cellulose carbamate derivatives presented in this work could be promising chiral cation exchangers for HPLC enantiomer separations.
Recovery Techniques Enabling Circular Chemistry from Wastewater
Authors: Elhami Vahideh , Antunes Evelyn C. , Temmink Hardy , Schuur Boelo
Published: February 2022

In an era where it becomes less and less accepted to just send waste to landfills and release wastewater into the environment without treatment, numerous initiatives are pursued to facilitate chemical production from waste. This includes microbial conversions of waste in digesters, and with this type of approach, a variety of chemicals can be produced. Typical for digestion systems is that the products are present only in (very) dilute amounts. For such productions to be technically and economically interesting to pursue, it is of key importance that effective product recovery strategies are being developed. In this review, we focus on the recovery of biologically produced carboxylic acids, including volatile fatty acids (VFAs), medium-chain carboxylic acids (MCCAs), long-chain dicarboxylic acids (LCDAs) being directly produced by microorganisms, and indirectly produced unsaturated short-chain acids (USCA), as well as polymers. Key recovery techniques for carboxylic acids in solution include liquid-liquid extraction, adsorption, and membrane separations. The route toward USCA is discussed, including their production by thermal treatment of intracellular polyhydroxyalkanoates (PHA) polymers and the downstream separations. Polymers included in this review are extracellular polymeric substances (EPS). Strategies for fractionation of the different fractions of EPS are discussed, aiming at the valorization of both polysaccharides and proteins. It is concluded that several separation strategies have the potential to further develop the wastewater valorization chains.
Molecular Pathological Diagnosis of Thyroid Tumors Using Spatially Resolved Metabolomics
Authors: Huang Luojiao , Mao Xinxin , Sun Chenglong , Li Tiegang , Song Xiaowei , Li Jiangshuo , Gao Shanshan , Zhang Ruiping , Chen Jie , He Jiuming , Abliz Zeper
Published: February 2022

The pathological diagnosis of benign and malignant follicular thyroid tumors remains a major challenge using the current histopathological technique. To improve diagnosis accuracy, spatially resolved metabolomics analysis based on air flow-assisted desorption electrospray ionization mass spectrometry imaging (AFADESI-MSI) technique was used to establish a molecular diagnostic strategy for discriminating four pathological types of thyroid tumor. Without any specific labels, numerous metabolite features with their spatial distribution information can be acquired by AFADESI-MSI. The underlying metabolic heterogeneity can be visualized in line with the cellular heterogeneity in native tumor tissue. Through micro-regional feature extraction and in situ metabolomics analysis, three sets of metabolic biomarkers for the visual discrimination of benign follicular adenoma and differentiated thyroid carcinomas were discovered. Additionally, the automated prediction of tumor foci was supported by a diagnostic model based on the metabolic profile of 65 thyroid nodules. The model prediction accuracy was 83.3% when a test set of 12 independent samples was used. This diagnostic strategy presents a new way of performing in situ pathological examinations using small molecular biomarkers and provides a model diagnosis for clinically indeterminate thyroid tumor cases.
In Vitro Antileishmanial and Antitrypanosomal Activities of Plicataloside Isolated from the Leaf Latex of Aloe rugosifolia Gilbert & Sebsebe (Asphodelaceae)
Authors: Chemeda Gete , Bisrat Daniel , Yeshak Mariamawit Y. , Asres Kaleab
Published: February 2022

Trypanosomiasis and leishmaniasis are among the major neglected diseases that affect poor people, mainly in developing countries. In Ethiopia, the latex of Aloe rugosifolia Gilbert & Sebsebe is traditionally used for the treatment of protozoal diseases, among others. In this study, the in vitro antitrypanosomal activity of the leaf latex of A. rugosifolia was evaluated against Trypanosoma congolense field isolate using in vitro motility and in vivo infectivity tests. The latex was also tested against the promastigotes of Leishmania aethiopica and L. donovani clinical isolates using alamar blue assay. Preparative thin-layer chromatography of the latex afforded a naphthalene derivative identified as plicataloside (2,8-O,O-di-(β-D-glucopyranosyl)-1,2,8-trihydroxy-3-methyl-naphthalene) by means of spectroscopic techniques (HRESI-MS, 1H, 13C-NMR). Results of the study demonstrated that at 4.0 mg/mL concentration plicataloside arrested mobility of trypanosomes within 30 min of incubation period. Furthermore, plicataloside completely eliminated subsequent infectivity in mice for 30 days at concentrations of 4.0 and 2.0 mg/mL. Plicataloside also displayed antileishmanial activity against the promastigotes of L. aethopica and L. donovani with IC50 values 14.22 ± 0.41 µg/mL (27.66 ± 0.80 µM) and 18.86 ± 0.03 µg/mL (36.69 ± 0.06 µM), respectively. Thus, plicataloside may be used as a scaffold for the development of novel drugs effective against trypanosomiasis and leishmaniasis.
Hemodynamics and Wall Shear Stress of Blood Vessels in Aortic Coarctation with Computational Fluid Dynamics Simulation
Authors: Kim Gi-Beum , Park Kwang-Hyun , Kim Seong-Jong
Published: February 2022

The purpose of this study was to identify the characteristics of blood flow in aortic coarctation based on stenotic shape structure, stenosis rate, and the distribution of the wall load delivered into the blood vessels and to predict the impact on aneurysm formation and rupture of blood vessels by using a computational fluid dynamics modeling method. It was applied on the blood flow in abdominal aortic blood vessels in which stenosis occurred by using the commercial finite element software ADINA on fluid-solid interactions. The results of modeling, with an increasing stenosis rate and Reynolds number, showed the pressure drop was increased and the velocity was greatly changed. When the stenosis rate was the same, the pressure drop and the velocity change were larger in the stenosis with a symmetric structure than in the stenosis with an asymmetric one. Maximal changes in wall shear stress were observed in the area before stenosis and minimal changes were shown in stenosis areas. The minimal shear stress occurred at different locations depending on the stenosis shape models. With an increasing stenosis rate and Reynolds number, the maximal wall shear stress was increased and the minimal wall shear stress was decreased. Through such studies, it is thought that the characteristics of blood flow in the abdominal aorta where a stenosis is formed will be helpful in understanding the mechanism of growth of atherosclerosis and the occurrence and rupture of the abdominal aortic flow.