bluuebunny/crossref_metadata_2025 huggingface dataset:
The African Wastewater Resistome: Identifying Knowledge Gaps to Inform Future Research Directions
Authors: Abia Akebe , Baloyi Themba , Traore Afsatou , Potgieter Natasha
Published: April 2023

Antimicrobial resistance (AMR) is a growing global public health threat. Furthermore, wastewater is increasingly recognized as a significant environmental reservoir for AMR. Wastewater is a complex mixture of organic and inorganic compounds, including antibiotics and other antimicrobial agents, discharged from hospitals, pharmaceutical industries, and households. Therefore, wastewater treatment plants (WWTPs) are critical components of urban infrastructure that play a vital role in protecting public health and the environment. However, they can also be a source of AMR. WWTPs serve as a point of convergence for antibiotics and resistant bacteria from various sources, creating an environment that favours the selection and spread of AMR. The effluent from WWTPs can also contaminate surface freshwater and groundwater resources, which can subsequently spread resistant bacteria to the wider environment. In Africa, the prevalence of AMR in wastewater is of particular concern due to the inadequate sanitation and wastewater treatment facilities, coupled with the overuse and misuse of antibiotics in healthcare and agriculture. Therefore, the present review evaluated studies that reported on wastewater in Africa between 2012 and 2022 to identify knowledge gaps and propose future perspectives, informing the use of wastewater-based epidemiology as a proxy for determining the resistome circulating within the continent. The study found that although wastewater resistome studies have increased over time in Africa, this is not the case in every country, with most studies conducted in South Africa. Furthermore, the study identified, among others, methodology and reporting gaps, driven by a lack of skills. Finally, the review suggests solutions including standardisation of protocols in wastewater resistome works and an urgent need to build genomic skills within the continent to handle the big data generated from these studies.
Finite Element Simulation and Experimental Investigation of Nanostructuring Burnishing AISI 52100 Steel Using an Inclined Flat Cylindrical Tool
Authors: Kuznetsov Victor , Smolin Igor , Skorobogatov Andrey , Akhmetov Ayan
Published: April 2023

This article is devoted to the development of a sliding burnishing scheme using a flat cylindrical indenter. The previously established patterns of nanostructured state formation in the AISI 52100 steel subsurface layer showed a need to create a special tool with a variable tilt angle of the indenter and with force regulation. A new tool with a cubic boron nitride indenter opens wide possibilities for nanostructuring burnishing of hardened bearing steel. Firstly, a flat cylindrical indenter has high durability due to repeated rotation around its axis. Secondly, the change of the tilt angle to the treated surface allows controlling the contact compression pressure and plastic shear deformation, which determines the formation of a nanostructured state of the material by the method of severe plastic deformation (SPD). The purpose of the work is to determine the optimal parameters of the process and tool in order to form a nanostructure and significantly increase surface layer microhardness. The goal was achieved by the methods of finite element modeling (FEM) and experimental studies of burnishing when the indenter tilt angle changes from 0.5° to 2.5° under dry processing conditions. Numerical simulation of the process made it possible to establish optimal values of the indenter tilt angle of 2° and the burnishing force 250 N according to the criteria of maximum contact pressure and cumulative deformation. The experimental studies of cumulative deformations and the coefficient of friction by the method of burnishing a split disc and dynamometry of the process confirmed the FEM results. The transmission microscopy, durometry, and 3D surface profilometry showed the sensitivity of nanocrystallite sizes, microhardness, and roughness to an indenter tilt angle and confirmed the optimality of the established tilt angle value.
Colorectal Cancer Cell Spheroids Co-Cultured with Molecularly Imprinted Fluorescent Particles Targeting Sialic Acid Show Preserved Cell Viability
Authors: Sjöberg Thomas , El-Schich Zahra , Rurack Knut , Gjörloff Wingren Anette
Published: April 2023

In vitro cultured 3D models of CRC have been demonstrated to hold considerable worth in drug discovery, drug resistance analysis, and in studying cell-cell and cell-matrix interactions that occur in the tumor microenvironment. The 3D models resemble the in vivo physiological microenvironment by replicating the cell type composition and tissue architecture. Molecularly imprinted polymers (MIPs) have been investigated for use instead of antibodies against small non-immunogenic structures, such as sialic acid (SA). Glyco-conjugates including SA are present on all cells, and often deregulated on cancer cells. Here, we present a novel approach for targeting and detecting colorectal cancer cells (CRC) by using in vitro cultured HT29 3D spheroids co-cultured in vitro with either fluorescent MIPs targeting SA, SA-MIPs, or the two lectins targeting SA, MAL I, and SNA. Both formaldehyde-fixed and viable HT29 3D spheroids with or without SA-MIPs were imaged in 3D by confocal microscopy. The results revealed a preserved cell morphology and viability of the HT29 3D spheroids co-cultured in vitro with SA-MIPs. However, the lectins MAL I and SNA targeting the α-2,3 or α-2,6 SA glycosidic linkages, respectively, affected the cell viability when co-cultured with the viable HT29 3D spheroids, and no living cells could be detected. Here, we have shown that the SA-MIPs could be used as a safe and low-cost diagnostic tool for targeting and detecting cancer cells in a physiologically relevant 3D cancer model in vitro.
Comparison of Topologies Generated by Evolutionary Neural Architecture Search
Authors: Yoo YongSuk , Park Manbok , Park Kang-Moon
Published: April 2023

Neural Architecture Search (NAS) has been widely applied across various fields, revealing intriguing patterns in the resulting optimized topologies. In this paper, we compare the topologies generated by NAS across two different experiments: linguistic grammaticality judgment and the MNIST task. Our analysis reveals a distinctive fork-like structure that consistently emerges in both experiments. Interestingly, this structure is highly effective despite not being typically designed by human experts. The emergence of this fork-like structure sheds new light on the potential of NAS to provide alternative designs that go beyond incremental improvements. Our paper offers a fresh perspective on automated architecture design, highlighting the potential of NAS to enable innovative approaches that can be applied across multiple domains.
Application of Neural Network Algorithms for Central Wavelength Determination of Fiber Optic Sensors
Authors: Agliullin Timur , Anfinogentov Vladimir , Misbakhov Rustam , Morozov Oleg , Nasybullin Aydar , Sakhabutdinov Airat , Valeev Bulat
Published: April 2023

Fiber Bragg gratings are sensitive elements in fiber optic sensor networks, and this paper discusses the practicalities of using neural network algorithms to determine their central wavelengths. The problem is to determine the central wavelength of a single sensor, the parameters of which are obtained using a low-resolution spectrum analyzer. The configuration of the neural network and the algorithm for producing the training and control datasets are specified. The training results for the selected neural network configuration demonstrated that the proposed method could determine the position of the central wavelength with a resolution two and a half orders of magnitude higher than the resolution of the input data sampling. The obtained results demonstrate that the approach makes it possible to determine the FBG central wavelength shift with an error not exceeding ~0.5 pm at a spectrum analyzer resolution of 167 pm.
Development of Equipment for Ski Mountaineering, a New Olympic Event
Authors: Bortolan Lorenzo , Pellegrini Barbara , Verdel Nina , Holmberg Hans-Christer , Supej Matej
Published: April 2023

Ski mountaineering, a new Olympic winter sport involving both climbing and descending snowy slopes, requires considerable physical and technical abilities, as well as highly specialized equipment. Herein, we briefly describe this equipment and its influence on performance and consider potential future advances. Skis, boots, and bindings must be light enough to facilitate climbing uphill (in which as much as 85% of the total racing time is spent) and, at the same time, provide stability and safety in often-challenging descents. A skier must be able to easily and rapidly attach and remove the adhesive skins under the skis that provide grip while skiing uphill. Poles and their baskets must be designed optimally to transfer propulsive force and help maintain balance. Despite the popularity of ski mountaineering, research on this sport is scarce, and we indicate a number of areas wherein improvements in equipment could potentially advance both performance and safety. Such advances must be based on a better understanding of the biomechanics of ski mountaineering, which could be obtained with novel sensor technology and can be best achieved via more extensive collaboration between researchers, skiers and their coaches, and manufacturers of ski mountaineering equipment.
Re-Thinking Table Salt Reduction in Bread with Halophyte Plant Solutions
Authors: Barroca Maria João , Flores Catarina , Ressurreição Sandrine , Guiné Raquel , Osório Nádia , Moreira da Silva Aida
Published: April 2023

Sodium intake higher than it is physiologically necessary has been associated with some non-communicable diseases such as hypertension, cardiovascular disease, and stroke. Bread is commonly consumed and is a major source of sodium in the human diet. Among the interventions to reduce the salt content in bread, the incorporation of salty taste halophyte powder could be a promising strategy. In the present work, Sarcocornia perennis was incorporated as a food ingredient to substitute the salt (sodium) of white wheat bread (1.2% NaCl/0.47% sodium, flour basis). Powdered dried S. perennis was incorporated into bread by replacing the same amount of sodium (0.47%, flour basis) and half of the sodium concentration (0.235%, flour basis), respectively, B100 and B50 bread samples. The bread samples were analyzed to evaluate the impact of the sodium chloride replacement by S. perennis powder on total baking loss, specific volume, crumb color, textural properties, microbial activity, nutritional and mineral composition and sensory evaluation. The incorporation of S. perennis increased the specific volume but had no relevant impact on the textural properties of bread. Furthermore, the substitution of sodium chloride by S. perennis powder allowed a more colored (greenish and yellowish) and dark crumb leading to a lower whiteness index. Compared with control bread, the addition of S. perennis powder promoted a significant increase of all bread’s nutrients and minerals, namely calcium, phosphor, iron, and manganese. Besides the improvement of bread quality, B100, and B50 bread samples were both sensorily well accepted and with similar scores to all the evaluated sensorial attributes. Moreover, the reduction of sodium to half (0.235% sodium (flour basis) in bread (B50) did not affect the acceptability of tasters, as compared with B100 (0.47% sodium (flour basis)). Both new bread formulation has microbiological quality as ready-to-eat product. However, taking into account greater stability over time for microbial spoilage, mainly caused by fungi and yeasts, B50 bread is more promising. The B50 bread sample is also a potential strategy to obtain a sodium reduction of 50% in bread, which could be essential to reduce the overall sodium daily intake and bring important economic and public health benefits.
Genome Sequence and Phenotypic Analysis of a Protein Lysis-Negative, Attenuated Anthrax Vaccine Strain
Authors: Yuan Lu , Wang Dongshu , Chen Jie , Lyu Yufei , Feng Erling , Zhang Yan , Liu Xiankai , Wang Hengliang
Published: April 2023

Bacillus anthracis is a Gram-positive bacterium that causes the zoonotic disease anthrax. Here, we studied the characteristic phenotype and virulence attenuation of the putative No. II vaccine strain, PNO2, which was reportedly introduced from the Pasteur Institute in 1934. Characterization of the strain showed that, compared with the control strain, A16Q1, the attenuated PNO2 (PNO2D1) was phospholipase-positive, with impaired protein hydrolysis and significantly reduced sporulation. Additionally, PNO2D1 significantly extended the survival times of anthrax-challenged mice. An evolutionary tree analysis revealed that PNO2D1 was not a Pasteur strain but was more closely related to a Tsiankovskii strain. A database comparison revealed a seven-base insertion mutation in the nprR gene. Although it did not block nprR transcription, the insertion mutation resulted in the premature termination of protein translation. nprR deletion of A16Q1 resulted in a nonproteolytic phenotype that could not sporulate. The database comparison revealed that the abs gene is also prone to mutation, and the abs promoter activity was much lower in PNO2D1 than in A16Q1. Low abs expression may be an important reason for the decreased virulence of PNO2D1.
Secondary Lymphedema: Clinical Interdisciplinary Tricks to Overcome an Intriguing Disease
Authors: Mukenge Sylvain , Negrini Daniela , Alfieri Ottavio
Published: April 2023

Secondary lymphedema is a complex pathology which is very impairing to the patient, consisting of fluid accumulation in the tissue, accompanied by alteration of the interstitial fibrous tissue matrix, deposition of cellular debris and local inflammation. It develops mostly in limbs and/or external genitals because of demolishing oncological surgery with excision of local lymph nodes, or it may depend upon inflammatory or infective diseases, trauma, or congenital vascular malformation. Its treatment foresees various approaches, from simple postural attitude to physical therapy, to minimally invasive lymphatic microsurgery. This review focuses on the different types of evolving peripheral lymphedema and describes potential solutions to single objective symptoms. Particular attention is paid to the newest lymphatic microsurgical approaches, such as lymphatic grafting and lympho-venous shunt application, to successfully heal, in the long term, serious cases of secondary lymphedema of limbs or external genitals. The presented data also emphasize the potential role of minimally invasive microsurgery in enhancing the development of newly formed lymphatic meshes, focusing on the need for further accurate research in the development of microsurgical approaches to the lymphatic vascular system.
The Influence of Temperature on Anisotropic Wettability Revealed by Friction Force Measurement
Authors: Lin Zhen , Xiao Kangjian , Li Lijun , Zhang Yurong , Zhang Xiaolong , Chen Daobing , Xue Longjian
Published: April 2023

Anisotropic surfaces with special wettability under various temperatures are of both fundamental interest and practical importance in many fields. However, little attention has been paid to the surfaces at temperatures between room temperature and the boiling point of water, which is partially due to the lack of a suitable characterization technique. Here, using the MPCP (monitoring of the position of the capillary’s projection) technique, the influence of the temperature on the friction of a water droplet on the graphene-PDMS (GP) micropillar array (GP-MA) is investigated. The friction forces in the orthogonal directions and the anisotropy in the friction decrease when the GP-MA surface is heated up, based on the photothermal effect of graphene. The friction forces also decrease along the pre-stretching direction but increase in the orthogonal direction when the stretching is increased. The change in the contact area, the Marangoni flow inside a droplet, and the mass reduction are responsible for the temperature dependence. The findings strengthen our fundamental understanding of the dynamics of drop friction at high temperatures and could pave the way for the design of new functional surfaces with special wettabilities.
Fruit Color Preference of Frugivorous Birds in an Agroecosystem in Southcentral Mindanao, Philippines
Authors: Balasa Navel Kyla B. , Roquero Jirriza O. , Lidasan Asraf K. , Casim Lothy F. , Agduma Angelo Rellama , Tanalgo Krizler Cejuela
Published: April 2023

The removal of fruit is a consequence of plant–animal interactions, and is a vital step in the natural regeneration cycle of plant populations. This research aimed to determine the effect of fruit color and local landscape on plant–bird interactions in an agroecosystem in Southcentral Mindanao, Philippines. We set out 1500 artificial fruit models in ten sampling locations within an agroecosystem. We measured the difference in the proportion of predated/removed (%) fruit models and the risk between sites, fruit color, and predators. Approximately a quarter (24.53%) of the artificial fruit models deployed were predated, and the proportion of predation was significantly higher in the red fruit models (mean = 18.74 ± 9.84) compared to the green fruit models (mean = 11.67 ± 6.17). Birds were the most dominant predators compared to mammals and arthropods, and contributed to at least 60% of the predation of red fruits. Our findings are consistent with previous evidence showing birds’ preferences for darker fruit colors. Although landscape variables did not significantly affect fruit predation, tree cover may help increase these interactions. Overall, our study showed that agroecosystems can still support species of frugivorous birds, as indicated by high fruit predation rates, particularly by birds that can permeate different layers of the agroecosystem. Our findings demonstrate an important implication for habitat quality management within agroecosystems. Enriching agroecosystems with pioneer trees with dark-colored fleshy fruits is a sustainable greening strategy that would benefit frugivores and producers in this system.
Distribution Features of Deviation and Determination of a Tolerance Method for Prefabricated Concrete Components
Authors: Long Hao , Luo Xiaoyong , Liu Jinhong , Xiang Hongzhan
Published: April 2023

According to the current standards for prefabricated buildings, the dimensional tolerances of components are usually determined by experience, lacking a theoretical basis. This work demonstrates the mathematical distribution of the dimensional deviations of precast concrete components by measuring their three-dimensional dimensions. Utilizing the Kolmogorov–Smirnov test, the cumulative distribution function of dimension deviations was evaluated. In response to the fact that the tolerance division principle of equal upper and lower tolerance thresholds for prefabricated components in existing standards does not match the distribution of actual measured deviations of the components, this paper proposed a method for determining the tolerance values of prefabricated components based on the process capability index. The association between the process capability index and the qualification rate was utilized to determine the process capability index at a specified guarantee rate, which, in turn, determines the tolerance threshold values for various components. The results indicate that the range of unqualified random variables for the dimensional geometric parameters of the prefabricated components did not show a significant difference, with all values between 0.99 and 1.02. The coefficients of geometric parameter variation were all less than 0.0061, and the component dimensional deviation adhered to the normal distribution. By linking the process capability index with the pass rate, a process capability index of 0.55 at a guarantee rate of 90% was determined, along with the tolerance for various components.
Effect of Ce Content on the Chemical Looping Oxidative Dehydrogenation of Propane to Propylene over a VOx-CeO2/γ-Al2O3 Oxygen Carrier
Authors: Qiang Fangyuan , Guo Tuo , Nie Mengdong , Liu Yongzhuo , Wu Man , Guo Qingjie
Published: April 2023

The chemical looping oxidative dehydrogenation of propane to propylene (CL-ODHP) replaces molecular oxygen with lattice oxygen (Olatt) in oxygen carriers. This method boosts propylene selectivity by avoiding the deep oxidation of propane. Herein, a series of 10V-XCe/Al oxygen carriers with different Ce contents were prepared to realize different VOx-CeOy interactions. The effect of the Ce content in 10V-XCe/Al oxygen carriers on the CL-ODHP reaction was studied and the optimal Ce content was determined. CeO2 prevents the outward diffusion and evolution of Olatt in VOx carriers to the adsorbed electrophilic oxygen species (Oelec), effectively inhibiting the loss of Olatt, improving the selectivity of propylene, and extending the lifetime and activity of the oxygen carriers. After characterizing and analyzing the oxygen carriers, it was found that 10V-3Ce/Al has the highest specific surface area, highest oxygen capacity, and lowest reducibility. The 10V-3Ce/Al also delivers the highest oxidative dehydrogenation performance. At 550 °C, the average propylene and COx selectivity values of 10V-3Ce/Al were 81.87% and 7.28%, respectively (vs. 62.79% and 25.64% respectively, for 10V/Al). It is demonstrated that 10V-3Ce/Al exhibits good cycle stability with no significant decrease in catalytic performance after 15 cycles. In situ diffuse-reflectance infrared Fourier-transform spectroscopy indicates that CL-ODHP on 10V-3Ce/Al undergoes the Mars-van Krevelen mechanism. The migration and evolution of Olatt in oxygen carriers is controlled by reasonably modifying the metal oxide interactions to improve propylene yield. This work will thus guide the subsequent development of novel and efficient CL-ODHP oxygen carriers.
Mechanism and Kinetic Study on Synthesis of Methacrolein Catalyzed by Amine/Acid
Authors: Wang Tao , Li Jie , Yan Hanwen , Zhang Guoliang , Li Shifeng
Published: April 2023

Methacrolein (MAL) is an important intermediate extensively used in the manufacture of methyl methacrylate and other materials (polymers and resins). In this study, a series of secondary amines/acids were explored as catalysts for the condensation of formaldehyde and propionaldehyde to prepare MAL. It was found that the structure of the amines and acids directly affected the yield of MAL. The effect of the catalyst was closely related to the nucleophilicity of the amines as well as the steric hindrance effect, while acids also played a role as co-catalysts. Dibutylamine acetate was selected as the catalyst after investigation. The catalytic performance of the system was systematically studied by a series of single-factor experiments, including stirring rate, temperature, reaction time, acid/amine ratio, and the solvent, and the optimized reaction conditions were obtained. In the optimum condition, the yield of MAL was up to 97.3%. Kinetic experiments were performed for the condensation of formaldehyde and propionaldehyde to MAL, and the activation energies, reaction orders, and rate-limiting step of the reaction were determined. The results indicate that the decomposition of the Mannich base is a rate-limiting step.
Assessment of the Type of Paint on Performance of Rendering Mortars
Authors: Baltazar Luis G. , Morais Antonio
Published: April 2023

The aim of this work is to determine how the mechanical and physical properties of render mortars, in particular their moisture performance, are affected by the application of paint. In this study, three commercial paints, hydro-pliolite-based paint, acrylic paint and silicate paint, were applied as coating layers on render mortars formulated with different binders. The choice of the binders used (hydrated lime, natural hydraulic lime and cement) was related to the functional requirements that the renders have to fulfil according to the type of buildings where they are applied (i.e., new or old buildings). Firstly, the hardness and surface cohesion of the different painted and unpainted renders were analysed in order to investigate the effect of the type of paint on the mechanical strength of the render surface. The influence of the paints on the moisture behaviour of the renders was then investigated using the water capillarity test, the water vapour permeability test and the drying test. The results show that all the paints studied can cause a significant change in the behaviour of the renders in terms of moisture transport phenomena. Nevertheless, it can be concluded that acrylic paint has the greatest resistance to water absorption, but it is also the paint with the higher resistance to water vapour diffusion. Hydro pliolite paint was found to be adequate from the point of view of reducing moisture accumulation and is the most recommended for old buildings with hydrated lime or hydraulic lime-based renders.
Our Cases and Literature Review for Presence of Bladder Hernias in the Inguinal Region in Children
Authors: Kapisiz Alparslan , Karabulut Ramazan , Kaya Cem , Eryilmaz Sibel , Turkyilmaz Zafer , Atan Ali , Sonmez Kaan
Published: April 2023

Background: The rate of bladder injury during inguinal hernia repair in children is not well known. However, it is known that bladder injury during childhood inguinal hernia repair places a serious morbidity burden on children. We sought to determine an algorithm to avoid accidental bladder injuries. Methods: Reports that included pediatric patients with inguinal hernias containing the bladder were searched. Keywords and mesh term searches were conducted in the MEDLINE, Scopus, and Web of Science databases. We reviewed our clinical records and found that two patients had inguinal hernias containing the bladder. Results: Nineteen articles reporting on 26 patients diagnosed with the presence of the bladder within the inguinal canal from 1962 to 2021 were included in this article. Our two patients were added to this group. Diagnoses were made incidentally during genitourinary radiological examinations (n = 3), intraoperatively during hernia repair (n = 7), or due to clinical symptoms and findings (n = 18) after standard hernia repair. Bladder augmentation was required for three patients. Conclusions: During the operation, if there is any suspicion regarding the presence of the bladder in the inguinal region, we suggest performing a preoperative cystogram to confirm the position of the bladder and its injury. We recommend that the sac should be opened and the contents inspected before performing transfixion during high ligation of the hernia sac.
Positron Emission Tomography/Computed Tomography (PET/CT)-Based, Local Consolidative Radiotherapy after Chemoimmunotherapy in Metastatic, Non-Oncogene-Addicted Non-Small-Cell Lung Cancer (NSCLC)
Authors: Angelini Lucia , Pazos Montserrat , Käsmann Lukas , Manapov Farkhad
Published: April 2023

The optimal sequence of chemo/immuno- and radiotherapy (RT) in metastatic non-small-cell lung cancer (NSCLC) remains challenging. Here, we describe the case of a 58-year-old female patient with an initially metastasized NSCLC obtaining local and distance durable response after chemo-immunotherapy and local RT associated with immunotherapy maintenance. Our experience offers a valuable perspective in choosing how to combine therapies to ensure the longest possible response in patients with estimated poor prognosis.
Recent Developments in the Theory and Applicability of Swarm Search
Authors: Altshuler Yaniv
Published: April 2023

Swarm intelligence (SI) is a collective behaviour exhibited by groups of simple agents, such as ants, bees, and birds, which can achieve complex tasks that would be difficult or impossible for a single individual [...]
Technology-Enhanced Learning, Data Sharing, and Machine Learning Challenges in South African Education
Authors: Combrink Herkulaas MvE , Marivate Vukosi , Masikisiki Baphumelele
Published: April 2023

The objective of this paper was to scope the challenges associated with data-sharing governance for machine learning applications in education research (MLER) within the South African context. Machine learning applications have the potential to assist student success and identify areas where students require additional support. However, the implementation of these applications depends on the availability of quality data. This paper highlights the challenges in data-sharing policies across institutions and organisations that make it difficult to standardise data-sharing practices for MLER. This poses a challenge for South African researchers in the MLER space who wish to advance and innovate. The paper proposes viewpoints that policymakers must consider to overcome these challenges of data-sharing practices, ultimately allowing South African researchers to leverage the benefits of machine learning applications in education effectively. By addressing these challenges, South African institutions and organisations can improve educational outcomes and work toward the goal of inclusive and equitable education.
A Robust CCS Predictive Current Control for Photovoltaic Energy Storage System Based on a Nonlinear Disturbance Observer
Authors: Yang Hui , Long Huachuan , Zhang Qi , Sun Xiangdong
Published: April 2023

This article introduces a new control strategy for a bidirectional DC/DC converter used in photovoltaic energy storage systems (PV-ESSs), aimed to address the DC bus voltage deviation problem. The purpose of this paper is to design and practically implement a robust continuous control set predictive current control (CCS-PCC) method based on a nonlinear disturbance observer (NDO) to tightly regulate the common DC bus voltage in islanded DC microgrids. The CCS-PCC controller is used to replace the current loop PI controller, which effectively overcomes the shortcomings of the traditional linear lag control and improves the dynamic performance of the system. At the same time, the CCS-PCC method solves the inherent defect of finite control set predictive current control (FCS-PCC), where the switching frequency is not fixed. It effectively reduces the current ripple and realizes constant frequency control. In order to effectively suppress the DC bus voltage fluctuation during transients, the nonlinear disturbance observer is designed and combined with CCS-PCC. The feedforward method based on the NDO was utilized to enhance the disturbance rejection capability of the system. The simulation and experimental results show the feasibility and effectiveness of the proposed CCS-PCC+NDO approach, both during transient and steady-state operating conditions.
Two-Fluid Large-Eddy Simulation of Two-Phase Flow in Air-Sparged Hydrocyclone
Authors: Bukhari Mustafa , Fayed Hassan , Ragab Saad
Published: April 2023

The two-fluid (Euler–Euler) model and large-eddy simulation are used to compute the turbulent two-phase flow of air and water in a cyclonic flotation device known as an Air-Sparged Hydrocyclone (ASH). In the operation of ASH, air is injected through a porous cylindrical wall. The study considers a 48 mm diameter hydrocyclone and uses a block-structured fine mesh of 10.5 million hexagonal elements. The air-to-water injection ratio is 4, and a uniform air bubble diameter of 0.5 mm is specified. The flow field in ASH was investigated for the inlet flow rate of water of 30.6 L/min at different values of underflow exit pressure. The current simulations quantify the effects of the underflow exit pressure on the split ratio and the overall flow physics in ASH, including the distribution of the air volume fraction, water axial velocity, tangential velocity, and swirling-layer thickness. The loci of zero-axial velocity surfaces were determined for different exit pressures. The water split ratio through the overflow opening varies with underflow exit pressure as 6%, 8%, 16%, and 26% for 3, 4, 5, and 6 kPa, respectively. These results indicate that regulating the pressure at the underflow exit can be used to optimize the ASH’s performance. Turbulent energy spectra in different regions of the hydrocyclone were analyzed. Small-scale turbulence spectra at near-wall points exhibit f−4 law, where f is frequency. Whereas for points at the air-column interface, the energy spectra show an inertial subrange f−5/3 followed by a dissipative range of f−7 law.
Non-Destructive Detection of Different Pesticide Residues on the Surface of Hami Melon Classification Based on tHBA-ELM Algorithm and SWIR Hyperspectral Imaging
Authors: Hu Yating , Ma Benxue , Wang Huting , Li Yujie , Zhang Yuanjia , Yu Guowei
Published: April 2023

In the field of safety detection of fruits and vegetables, how to conduct non-destructive detection of pesticide residues is still a pressing problem to be solved. In response to the high cost and destructive nature of existing chemical detection methods, this study explored the potential of identifying different pesticide residues on Hami melon by short-wave infrared (SWIR) (spectral range of 1000–2500 nm) hyperspectral imaging (HSI) technology combined with machine learning. Firstly, the classification effects of classical classification models, namely extreme learning machine (ELM), support vector machine (SVM), and partial least squares discriminant analysis (PLS-DA) on pesticide residues on Hami melon were compared, ELM was selected as the benchmark model for subsequent optimization. Then, the effects of different preprocessing treatments on ELM were compared and analyzed to determine the most suitable spectral preprocessing treatment. The ELM model optimized by Honey Badger Algorithm (HBA) with adaptive t-distribution mutation strategy (tHBA-ELM) was proposed to improve the detection accuracy for the detection of pesticide residues on Hami melon. The primitive HBA algorithm was optimized by using adaptive t-distribution, which improved the structure of the population and increased the convergence speed. Compared the classification results of tHBA-ELM with HBA-ELM and ELM model optimized by genetic algorithm (GA-ELM), the tHBA-ELM model can accurately identify whether there were pesticide residues and different types of pesticides. The accuracy, precision, sensitivity, and F1-score of the test set was 93.50%, 93.73%, 93.50%, and 0.9355, respectively. Metaheuristic optimization algorithms can improve the classification performance of classical machine learning classification models. Among all the models, the performance of tHBA-ELM was satisfactory. The results indicated that SWIR-HSI coupled with tHBA-ELM can be used for the non-destructive detection of pesticide residues on Hami melon, which provided the theoretical basis and technical reference for the detection of pesticide residues in other fruits and vegetables.
Deep Learning Network of Amomum villosum Quality Classification and Origin Identification Based on X-ray Technology
Authors: Wu Zhouyou , Xue Qilong , Miao Peiqi , Li Chenfei , Liu Xinlong , Cheng Yukang , Miao Kunhong , Yu Yang , Li Zheng
Published: April 2023

A machine vision system based on a convolutional neural network (CNN) was proposed to sort Amomum villosum using X-ray non-destructive testing technology in this study. The Amomum villosum fruit network (AFNet) algorithm was developed to identify the internal structure for quality classification and origin identification in this manuscript. This network model is composed of experimental features of Amomum villosum. In this study, we adopted a binary classification method twice consecutive to identify the origin and quality of Amomum villosum. The results show that the accuracy, precision, and specificity of the AFNet for quality classification were 96.33%, 96.27%, and 100.0%, respectively, achieving higher accuracy than traditional CNN under the condition of faster operation speed. In addition, the model can also achieve an accuracy of 90.60% for the identification of places of origin. The accuracy of multi-category classification performed later with the consistent network structure is lower than that of the cascaded CNNs solution. With this intelligent feature recognition model, the internal structure information of Amomum villosum can be determined based on X-ray technology. Its application will play a positive role to improve industrial production efficiency.
Rapid and Portable Detection of Hg and Cd in Grain Samples Based on Novel Catalytic Pyrolysis Composite Trap Coupled with Miniature Atomic Absorption Spectrometry
Authors: Liu Tengpeng , Liu Jixin , Mao Xuefei , Jiang Xiaoming , Zhao Yabo , Qian Yongzhong
Published: April 2023

As toxic metals, Hg and Cd are a concern for food safety and human health; their rapid and portable analysis is still a challenge. A portable and rapid Hg–Cd analyzer constructed from a metal–ceramic heater (MCH)-based electrothermal vaporizer (ETV), an on-line catalytic pyrolysis furnace (CPF), a composite Pt/Ni trap, and a homemade miniature atomic absorption spectrometer (AAS) was proposed for grain analysis in this work. To enhance sensitivity, a new folded light path was designed for simultaneous Hg and Cd analysis using charge coupled device (CCD) in AAS. To eliminate the grain matrix interference, a catalytic pyrolysis furnace with aluminum oxide fillers was utilized to couple with a composite Pt/Ni trap. The method limits of detection (LODs) were 1.1 μg/kg and 0.3 μg/kg for Hg and Cd using a 20 mg grain sample, fulfilling the real sample analysis to monitor the grain contamination quickly; linearity R2 > 0.995 was reached only using standard solution calibration, indicating the sample was free of grain matrix interference. The favorable analytical accuracy and precision were validated by analyzing real and certified reference material (CRM) grains with recoveries of 97–103% and 96–111% for Hg and Cd, respectively. The total analysis time was less than 5 min without sample digestion or use of any chemicals, and the instrumental size and power consumption were <14 kg and 270 W, respectively. Compared with other rapid methods, this newly designed Hg–Cd analyzer is proven to be simple, portable, and robust and is, thus, suitable to quickly monitor Hg and Cd contamination in the field to protect grain and food safety.
Designing Hyperbolic Tangent Sigmoid Function for Solving the Williamson Nanofluid Model
Authors: Souayeh Basma , Sabir Zulqurnain
Published: April 2023

This study shows the design of the novel hyperbolic tangent sigmoid function for the numerical treatment of the Williamson nanofluid model (WNM), which is categorized as velocity, concentration, and temperature. A process of a deep neural network using fifteen and thirty neurons is presented to solve the model. The hyperbolic tangent sigmoid transfer function is used in the process of both hidden layers. The optimization is performed through the Bayesian regularization approach (BRA) to solve the WNM. A targeted dataset through the Adam scheme is achieved that is further accomplished using the procedure of training, testing, and verification with ratios of 0.15, 0.13, and 0.72. The correctness of the deep neural network along with the BRA is performed through the overlapping of the solutions. The small calculated absolute error values also enhance the accurateness of the designed procedure. Moreover, the statistical observations are authenticated to reduce the mean square error for the nonlinear WNM.
The Digital Heritage of the Battle to Contain COVID-19 in Australia and Its Implications for Heritage Studies
Authors: Spennemann Dirk H.R.
Published: April 2023

One of the major public health measures to manage and contain the outbreak of the COVID-19 pandemic was to engage in systematic contact tracing, which required gastronomy, community and sporting venues to keep patron registers. Stand-alone and web-based applications, developed by a range of private IT providers, soon replaced pen-and-paper lists. With the introduction of a uniform, state-wide, mandatory data collection system, these private applications became obsolete. Although only active for four months, these applications paved the way for the public acceptance of state-administered collection systems that allowed for an unprecedented, centralized tracking system of the movements of the entire population. This paper discusses the cultural significance of these applications as a game changer in the debate on civil liberties, and addresses the question of how the materiality, or lack thereof, of this digital heritage affects the management of ephemeral smartphone applications, and its preservation for future generations.
Durable Consumption-Based Asset Pricing Model with Foreign Factors for the Korean Stock Market
Authors: Cho Cheol-Keun , Jang Bosung
Published: April 2023

This paper explores the implications of consumption heterogeneity between domestic and foreign investors on the cross-section of stock returns in a host country. We argue that foreign investors in a small open economy integrated into global financial markets may face consumption risk, which could result in risk premia being reflected in stock returns. To account for the potential influence of foreign investors on asset prices in a host country, we develop a two-country durable consumption model under market incompleteness, which extends the one-country durable consumption model. The proposed model includes both domestic and foreign pricing factors. We investigate the empirical performance of our model with Fama–French portfolios for Korea, taking U.S. investors as representative foreign investors. The empirical results advocate the two-country durable consumption model, confirming the significant role of foreign factors in the cross-section of domestic stock returns. Additionally, R2 tests conducted with different sets of test assets show that the explanatory power of our model is comparable to that of the Fama–French three-factor model.
NT-proBNP Is a Predictor of Mortality in Adults with Pulmonary Arterial Hypertension Associated with Congenital Heart Disease
Authors: Maurer Susanne J. , Habdank Veronika , Hörer Jürgen , Ewert Peter , Tutarel Oktay
Published: April 2023

Background: About 5–10% of adults with congenital heart disease (ACHD) will develop pulmonary arterial hypertension (PAH), which is associated with significant mortality. Studies on risk factors for poor outcome in a contemporary cohort of these patients with PAH associated with CHD (PAH-CHD) are rare. Methods: In this retrospective, single-center study, adult patients with the diagnosis PAH-CHD who had at least one contact as an outpatient or inpatient at the German Heart Centre Munich during the period January 2010–September 2019 were included. Patients with PAH without a CHD were excluded. The primary endpoint was all-cause mortality. Results: Altogether, 158 patients (mean age 39.9 ± 15.4 years, female 64.6%) were included in the study. A pre-tricuspid shunt was present in 17.7%, other shunts in 51.3%, PAH associated with complex CHD in 22.8%, and segmental PAH in 8.2%. An NT-proBNP measurement at baseline was available in 95 patients (60.1%). During a median follow-up of 5.37 years [IQR 1.76–8.63], the primary endpoint occurred in 10 patients (6.7%). On univariate analysis, CRP (log) (HR 3.35, 95% CI (1.07–10.48), p = 0.037), NT-proBNP (log) (HR: 7.10, 95% CI: 1.57–32.23, p = 0.011), and uric acid (HR: 1.37, 95% CI: 1.05–1.79, p = 0.020) were predictors of the primary endpoint. On multivariate analysis, only NT-proBNP (log) (HR: 6.91, 95% CI: 1.36–35.02, p = 0.0196) remained as an independent predictor. Conclusion: NT-proBNP is an independent predictor of all-cause mortality in a contemporary cohort of PAH-CHD patients. The role of CRP and uric acid should be further assessed in future studies.
3-Tesla T2 Mapping Magnetic Resonance Imaging for Evaluation of SLAP Lesions in Patients with Shoulder Pain: An Arthroscopy-Controlled Study
Authors: Stein Patrick , Wuennemann Felix , Schneider Thomas , Zeifang Felix , Burkholder Iris , Weber Marc-André , Kauczor Hans-Ulrich , Rehnitz Christoph
Published: April 2023

This study investigated the ability of T2 mapping to assess the glenoid labrum and to differentiate between healthy labral substances and superior labral anterior posterior (SLAP) lesions using arthroscopy as the gold standard. Eighteen patients (mean age: 52.4 ± 14.72 years, 12 men) with shoulder pain were examined using 3-Tesla T2 mapping. All the patients underwent shoulder arthroscopy. Using morphological sequences for correlation, regions of interest covering the entire labral substance were placed in the corresponding T2 maps. The diagnostic cutoff values, sensitivities, and specificities, as well as the inter-reader correlation coefficients (ICCs) determined by two independent radiologists, were calculated. The mean T2 value was 20.8 ± 2.4 ms for the healthy labral substances and 37.7 ± 10.63 ms in the patients with SLAP lesions. The maximum T2 value in normal labrum (21.2 ms) was lower than the minimum T2 value in the patients with SLAP lesions (27.8 ms), leading to sensitivities, specificities, and positive and negative predictive values of 100% (95% CI 54.1–100.0) for all the cutoff values between 21.2 and 27.8 ms. The ICCs ranged from 0.91 to 0.99. In summary, the data suggest that evaluation and quantification of the labral (ultra)structural integrity using T2 mapping may allow discrimination between arthroscopically confirmed SLAP lesions and a healthy glenoid labrum. T2 mapping may therefore be helpful in diagnosing patients with suspected labral damage.
The Burden of Survivorship: Survivor Guilt and Its Association with Psychiatric Sequelae in COVID-19 Patients
Authors: Palladini Mariagrazia , Mazza Mario Gennaro , Scalabrini Andrea , Rovere Querini Patrizia , Poletti Sara , Benedetti Francesco
Published: April 2023

COVID-19 survivors struggle with intense depressive and post-traumatic symptoms in sub-acute stages. Survivor guilt may affect post-acute psychopathology. Herein, we aim to unveil the potential affective mechanism underpinning post-COVID psychiatric implications by focusing on the association of survivor guilt with psychopathology and maladaptive attributional style. At one month after discharge, we evaluated symptoms of depression on The Zung Severity Rating Scale (ZSDS), post-traumatic distress on Impact of Event Scale-Revised (IES-R), and sleep disturbances on the Women’s Health Initiative Insomnia Rating Scale (WHIIRS) in 195 COVID-19 survivors. Interpersonal Guilt Rating Scale (IGRS-15) rated survivor guilt. A discrepancy score between the burden of depression and post-traumatic distress symptoms was computed individually. Dysfunctional depressive attributions were assessed through the Cognition Questionnaire (CQ). Survivor guilt significantly predicts all evaluated psychopathological dimensions. Moreover, higher rates of survivor guilt were associated with an overlap between post-traumatic and depressive symptomatology, thus suggesting that survivor guilt equally sustains both psychiatric manifestations. Finally, survivor guilt fully mediated the relationship between dysfunctional depressive attributions and the discrepancy index. Our results confirm survivor guilt as a clinically relevant form of suffering related to psychopathological dimensions of post COVID-19 infection, gaining the status of a specific phenomenon and a promising treatment target.