bluuebunny/crossref_metadata_2025 huggingface dataset:
Methane Combustion over Zeolite-Supported Palladium-Based Catalysts
Authors: Tao Jinxiong , Liu Yuxi , Deng Jiguang , Jing Lin , Hou Zhiquan , Wei Lu , Wang Zhiwei , Dai Hongxing
Published: August 2023

The emission of methane leads to the increase in the methane concentration in the atmosphere, which not only wastes resources but also intensifies the greenhouse effect and brings about serious environmental problems. Catalytic combustion can completely convert methane into carbon dioxide and water at low temperatures. However, the catalytic activities of the conventional supported palladium catalysts (e.g., Pd/Al2O3 and Pd/ZrO2) are easy to decrease or the two catalysts can even be deactivated under actual harsh reaction conditions (high temperatures, steam- and sulfur dioxide-containing atmospheres, etc.). Recently, noble metal catalysts supported on zeolites with ordered pores and good thermal stability have attracted much attention. This review article summarizes the recent progress on the development and characteristics of zeolite-supported noble metal catalysts for the combustion of methane. The effects of framework structures, silica/alumina ratios, acidity, doping of alkali metals or transition metals, particle sizes and distributions, and their locations of/in the zeolites on methane combustion activity are discussed. The importance of developing high-performance catalysts under realistic operation conditions is highlighted. In addition, the related research work on catalytic methane combustion in the future is also envisioned.
Glia Cells Control Olfactory Neurogenesis by Fine-Tuning CXCL12
Authors: Dietz André , Senf Katja , Karius Julia , Stumm Ralf , Neuhaus Eva Maria
Published: August 2023

Olfaction depends on lifelong production of sensory neurons from CXCR4 expressing neurogenic stem cells. Signaling by CXCR4 depends on the concentration of CXCL12, CXCR4’s principal ligand. Here, we use several genetic models to investigate how regulation of CXCL12 in the olfactory stem cell niche adjusts neurogenesis. We identify subepithelial tissue and sustentacular cells, the olfactory glia, as main CXCL12 sources. Lamina propria-derived CXCL12 accumulates on quiescent gliogenic stem cells via heparan sulfate. Additionally, CXCL12 is secreted within the olfactory epithelium by sustentacular cells. Both sustentacular-cell-derived and lamina propria-derived CXCL12 are required for CXCR4 activation. ACKR3, a high-affinity CXCL12 scavenger, is expressed by mature glial cells and titrates CXCL12. The accurate adjustment of CXCL12 by ACKR3 is critical for CXCR4-dependent proliferation of neuronal stem cells and for proper lineage progression. Overall, these findings establish precise regulation of CXCL12 by glia cells as a prerequisite for CXCR4-dependent neurogenesis and identify ACKR3 as a scavenger influencing tissue homeostasis beyond embryonic development.
Dynamic and Steady-State Simulation Study for the Stabilization of Natural Gas Condensate and CO2 Removal through Heating and Pressure Reduction
Authors: Ehsan Mohsin , Ali Usman , Sher Farooq , Abubakar Hafiz M. , Basit Muhammad Fazal Ul
Published: August 2023

Stabilization of condensate is a highly energy-consuming process compared to other oil and gas processes. There is a need to reduce this energy consumption. Therefore, the present work aims to simulate the stabilization unit in terms of available energy and on-spec stabilized condensate products. Natural gas condensate liquids (NGL) need to be stabilized by eliminating lighter hydrocarbon gases and acid gases before being sent to the refinery. Stabilized NGL has the vapor pressure determined as a Reid vapor pressure of 7 psia, showing that light components did not evolve as a separate gas phase. Stabilization and CO2 removal was performed through the distillation method by heating and pressure reduction using steady state and dynamic simulation through Aspen HYSYS. Different process alterations around the exchanger and column have been studied based on the utilities available for the stabilization and CO2 removal process. Sensitivity studies, including the impact of CO2 concentration, the temperature at the inlet of the stabilizer flash separator, and the dynamic simulation for the PID controller, have been performed to analyze the impact on the process parameters, such as Reid vapor pressure (RVP) and CO2 of the rundown air cooler and heat duties of the exchangers. Actual plant data have been used for the validation of process simulation values for the accuracy of the condensate stabilization unit model. Based on the scenarios analyzed, it can be concluded that the nitrogen stripping method achieved 7 ppmv CO2 and 7 psia RVP in the condensate from the cooler outlet, while a variation of 29 bpd was observed for the stabilized condensate flowrate throughout all scenarios with data validation showing 0.24% discrepancy between Aspen Hysys data and actual plant data.
Extraction and Characterization of Cellulose Obtained from Banana Plant Pseudostem
Authors: Nascimento Rosa E. A. , Carvalheira Mónica , Crespo João G. , Neves Luísa A.
Published: August 2023

Each year, the amount of residue generated from food production increases, caused by the continuous population growth. Banana is one of the most consumed fruits in the world, with an annual production of 116.78 million tonnes. However, just 12 wt% of the plant, corresponding to the bunch, is effectively used. After the bunch is harvested, the rest of the plant is disposed of as residue, the pseudostem (PS) being the main constituent. Aiming to give an added-value application to the PS, this work is focused on the extraction of cellulose from this waste. For this, three different fractions of PS particles—a non-classified fraction (milled but without sieving), a fine fraction (≤180 μm), and a coarse fraction (≥2000 μm)—and three extraction methods—alkaline-acid hydrolysis, enzymatic hydrolysis, and TEMPO oxidation—were studied to determine the most promising method for the cellulose extraction from the PS. The alkaline-acid hydrolysis samples presented a higher number of amorphous compounds, resulting in lower crystallinity (13.50% for the non-classified fraction). The TEMPO-oxidation process, despite allowing the highest cellulose extraction yield (25.25 ± 0.08% on a dried basis), resulted in samples with lower thermal stability (up to 200 °C). The most promising extraction method was enzymatic, allowing the extraction of 14.58 ± 0.30% of cellulose (dried basis) and obtaining extracts with the highest crystallinity (68.98% for the non-classified fraction) and thermal stability (until 250 °C).
Torus-Connected Toroids: An Efficient Topology for Interconnection Networks
Authors: Bossard Antoine
Published: August 2023

Recent supercomputers embody hundreds of thousands of compute nodes, and sometimes millions; as such, they are massively parallel systems. Node interconnection is thus critical to maximise the computing performance, and the torus topology has come out as a popular solution to this crucial issue. This is the case, for example, for the interconnection network of the Fujitsu Fugaku, which was ranked world no. 1 until May 2022 and is the world no. 2 at the time of the writing of this article. Here, the number of dimensions used by the network topology of such torus-based interconnects stays rather low: it is equal to three for the Fujitsu Fugaku’s interconnect. As a result, it is necessary to greatly increase the arity of the underlying torus topology to be able to connect the numerous compute nodes involved, and this is eventually at the cost of a higher network diameter. Aiming at avoiding such a dramatic diameter rise, topologies can also combine several layers: such interconnects are called hierarchical interconnection networks (HIN). We propose, in this paper, which extends an earlier study, a novel interconnect topology for massively parallel systems, torus-connected toroids (TCT), whose advantage compared to existing topologies is that while it retains the torus topology for its desirable properties, the TCT network topology combines it with an additional layer, toroids, in order to significantly lower the network diameter. We both theoretically and empirically evaluate our proposal and quantitatively compare it to conventional approaches, which the TCT topology is shown to supersede.
Hubbard Bands and Exotic States in Doped and Undoped Mott Systems: The Kotliar–Ruckenstein Representation
Authors: Irkhin Valentin Yu.
Published: August 2023

The slave–particle representation is a promising method to treat the properties of exotic strongly correlated systems. We develop a unified approach to describe both the paramagnetic state with possible spin–liquid features and states with strong long-range or short-range magnetic order. Combining the Kotliar–Ruckenstein representation and fractionalized spin–liquid deconfinement picture, the Mott transition and Hubbard subbands are considered. The spectrum in the insulating state is significantly affected by the presence of the spinon spin–liquid spectrum and a hidden Fermi surface. Presenting a modification of the Kotliar–Ruckenstein representation in the spin–wave region, we treat the case of magnetic order, with special attention being paid to the half-metallic ferromagnetic state. The formation of small and large Fermi surfaces for doped current carriers in the antiferromagnetic state is also discussed.
Exploring the Biological Functions and Anti-Melanogenesis of Phallus indusiatus for Mushroom-Based Cosmetic Applications
Authors: Theeraraksakul Kanyanat , Jaengwang Kittitat , Choowongkomon Kiattawee , Tabtimmai Lueacha
Published: August 2023

Phallus indusiatus, or bamboo mushroom, has been reported for its nutraceutical properties, while its cosmeceutical properties remain unclear. In this study, we conducted extractions of whole, fresh P. indusiatus using both aqueous and ethanolic methods. Among the extracts, ultrasonic-assisted extraction method with DI showed the highest antioxidant activity compared to the others. For cosmeceutical assessment, we evaluated the extracts’ inhibitory effects against ECM-degrading enzymes and found that they exhibited a modest inhibitory effect of approximately 50%. Remarkably, ultrasonic-assisted extraction with DI demonstrated promising cosmeceutical properties. Additionally, pressure-assisted extraction with DI showed a potentially protective effect against H2O2-induced DNA damage. To investigate the anti-melanogenic effect on MNT-1 cells, we treated them with the extracts and observed a significant decrease in cellular tyrosinase activity under α-MSH stimulation. This resulted in a relative reduction in melanin content. Notably, autoclaving extraction exhibited a significantly greater anti-melanogenic effect than the other extracts at the lowest concentration tested. Furthermore, the extracts demonstrated a reduction in NO production under LPS-induced inflammation. Hot water extraction with DI and ethanol exhibited a stronger anti-inflammatory effect compared to diclofenac, without any cytotoxicity. These findings highlight the hidden cosmeceutical properties of P. indusiatus and suggest its potential use as a bioactive ingredient in cosmetic formulations.
Novel Approach to Grain Boundary Modification in Stainless and Duplex Steel L-PBF Components through In Situ Heat Treatment
Authors: Andani Mohsen Taheri , Sundararaghavan Veera , Misra Amit
Published: August 2023

Additive manufacturing (AM) has provided new possibilities for improving the grain boundary properties of metallic components. However, effectively modifying the microstructure, particularly the grain boundary properties, of laser powder bed fusion (L-PBF) components remains a challenge. Post-processing methods have shown some success in adjusting grain boundary angles, but they have limitations when it comes to complex geometries and internal features. In this study, we propose an innovative in situ heat treatment to control the grain boundary properties of L-PBF components. A model is proposed to predict the thermal cycle at a single point, and it is validated through experiments on 2507 super duplex steel and 316L austenitic steel samples. The results demonstrate that, by applying controlled in situ heat treatment, the dynamic recovery processes can be influenced, and thereby the grain boundary properties of the manufactured parts can be controlled. This proposed method improves our understanding of the impact of in situ heat treatment on grain boundary properties and offers potential for designing and fabricating high-performance L-PBF components. The findings from this study lay the groundwork for the further exploration of grain boundary engineering in metallic components using L-PBF. By leveraging in situ heat treatment, future research can open up new avenues in additive manufacturing, facilitating the production of advanced and high-quality metallic components.
Identification of Proteins Adsorbed on Hydroxyapatite Ceramics with a Preferred Orientation to a-Plane
Authors: Onuma Erika , Honda Takayuki , Yoshimura Hideyuki , Nishihara Tappei , Ogura Atsushi , Kanzawa Nobuyuki , Aizawa Mamoru
Published: August 2023

Protein adsorption is essential for determining material biocompatibility and promoting adherent cell growth. In this study, we focused on the a-plane structure of hydroxyapatite (HAp). This a-plane structure closely resembles the crystal plane where apatite is exposed in long bones. We conducted protein adsorption experiments using HAp ceramics with a preferred orientation to a-planes (aHAp), employing bovine serum albumin (BSA), lysozyme, and fetal bovine serum (FBS) as protein models to mimic the in vivo environment. Higher zeta potential and contact angle values were found in aHAp than in HAp ceramics fabricated from commercial HAp powder (iHAp). Bradford-quantified protein adsorption revealed BSA adsorption of 212 ng·mm−2 in aHAp and 28.4 ng mm−2 in iHAp. Furthermore, the Bradford-quantified protein adsorption values for FBS were 2.07 μg mm−2 in aHAp and 1.28 µg mm−2 in iHAp. Two-dimensional electrophoresis (2D-PAGE) showed a higher number of protein-derived major spots in aHAp (37 spots) than in iHAp (12 spots). Mass spectrometry analysis of the resulting 2D-PAGE gels revealed proteins adsorbed on aHAp, including secreted frizzled-related protein 3 and vitamin K epoxide reductase complex 1, which are involved in cellular bone differentiation. Overall, these proteins are expected to promote bone differentiation, representing a characteristic property of aHAp.
Hot Is Rich—An Enormous Diversity of Simple Trichal Cyanobacteria from Yellowstone Hot Springs
Authors: Kaštovský Jan , Johansen Jeffrey R. , Hauerová Radka , Akagha Mildred U.
Published: August 2023

In 2019, cyanobacterial samples were collected from thermal sites in Yellowstone National Park. In this paper, we discuss the considerable richness of representatives of simple filamentous cyanobacteria. Using a polyphasic approach, one new genus, Copelandiella, with two species (C. yellowstonensis and C. thermalis) and eight additional new species Albertania prattii, K. anagnostidisii, Kovacikia brockii, Leptolyngbya tildenae, L. vaporiphila, Nodosilinea calida, N. igneolacustris, and Oculatella castenholzii were described. At the same time, by analyzing our new molecular data, we concluded that other genera of trichal cyanobacteria can be merged with existing genera: species within the genus Plectolyngbya are herein transferred to Leptolyngbya, and if some nomenclatural issues are resolved, species within the genus Leptothermofonsia will be subsequently transferred to the genus Kovacikia, an earlier synonym.
Insight into Trophic Interactions of Spiders in Olive Groves with Integrated and Ecological Pest Management Using DNA Metabarcoding
Authors: Anđelić Dmitrović Barbara , Gajski Domagoj , Kos Tomislav , Jelić Mišel , Šerić Jelaska Lucija
Published: August 2023

Spiders act as one of the major predators among arthropods in agroecosystems and are crucial to the control of pest densities. As they are almost exclusively predators, they have developed a number of hunting strategies, which have consequently impacted their complex trophic interactions. The development of molecular biology methods for environmental DNA analysis has made it easier to analyze such complex trophic networks. In order to ascertain the trophic interactions of spiders, a sampling of spider species was carried out in two olive groves in Zadar County, Croatia, under integrated and ecological pest management. To construct the trophic networks of spiders, we performed DNA metabarcoding. The combined general and spider-excluding primers were able to recognize prey from 12 distinct orders in the guts of the 57 spiders. According to our results, spiders have a complex trophic network that exhibits seasonal and site-specific variations. The results obtained from both sites having different pest management also confirmed that spiders consumed phytophagous insects in the highest ratio, including some important pests, in comparison to other prey and that management and guild type had an impact on the predation of phytophagous insects.
A Review on the Genus Paramacrobiotus (Tardigrada) with a New Diagnostic Key
Authors: Kayastha Pushpalata , Mioduchowska Monika , Warguła Jędrzej , Kaczmarek Łukasz
Published: August 2023

Paramacrobiotus species have been described in almost every corner of the world. To date, 45 species have been reported from this genus. Among which, 13 belong to the areolatus group (without a microplacoid) and 32 belong to the richtersi group (with a microplacoid). The species’ presence in different climatic conditions and habitats provides evidence of their adaptation to various harsh environments. The species of the genus are both bisexual (diploid) and parthenogenetic (triploid). The bisexual species have external fertilization. And they are omnivorous whose diet consists of certain cyanobacteria, algae, fungi, rotifers, nematodes and juvenile tardigrades. The life history of species from this genus varies from species to species. Because the species has a strong predilection for cryptobiosis, numerous investigations involving anhydrobiosis have been conducted utilizing specimens from varied Paramacrobiotus species to date. In this review, we provide a concise summary of changes observed due to various cryptobiotic conditions in many species of this genus, the geographical distribution of all the species, feeding behaviour, life history, microbiome community, Wolbachia endosymbiont identification, reproduction, phylogeny and general taxonomy of the species from the genus Paramacrobiotus. Furthermore, we provide a new diagnostic key to the genus Paramacrobiotus based on the morphological and morphometric characters of adults and eggs.
Hybrid Methods for Fundus Image Analysis for Diagnosis of Diabetic Retinopathy Development Stages Based on Fusion Features
Authors: Alshahrani Mohammed , Al-Jabbar Mohammed , Senan Ebrahim Mohammed , Ahmed Ibrahim Abdulrab , Saif Jamil Abdulhamid Mohammed
Published: August 2023

Diabetic retinopathy (DR) is a complication of diabetes that damages the delicate blood vessels of the retina and leads to blindness. Ophthalmologists rely on diagnosing the retina by imaging the fundus. The process takes a long time and needs skilled doctors to diagnose and determine the stage of DR. Therefore, automatic techniques using artificial intelligence play an important role in analyzing fundus images for the detection of the stages of DR development. However, diagnosis using artificial intelligence techniques is a difficult task and passes through many stages, and the extraction of representative features is important in reaching satisfactory results. Convolutional Neural Network (CNN) models play an important and distinct role in extracting features with high accuracy. In this study, fundus images were used for the detection of the developmental stages of DR by two proposed methods, each with two systems. The first proposed method uses GoogLeNet with SVM and ResNet-18 with SVM. The second method uses Feed-Forward Neural Networks (FFNN) based on the hybrid features extracted by first using GoogLeNet, Fuzzy color histogram (FCH), Gray Level Co-occurrence Matrix (GLCM), and Local Binary Pattern (LBP); followed by ResNet-18, FCH, GLCM and LBP. All the proposed methods obtained superior results. The FFNN network with hybrid features of ResNet-18, FCH, GLCM, and LBP obtained 99.7% accuracy, 99.6% precision, 99.6% sensitivity, 100% specificity, and 99.86% AUC.
The Correlation of In Vivo MR Spectroscopy and Ex Vivo 2-Hydroxyglutarate Concentration for the Prediction of Isocitrate Dehydrogenase Mutation Status in Diffuse Glioma
Authors: van Dijken Bart R. J. , Jeltema Hanne-Rinck , Kłos Justyna , van Laar Peter Jan , Enting Roelien H. , Maatman Ronald G. H. J. , Bijsterveld Klaas , Den Dunnen Wilfred F. A. , Dierckx Rudi A. , Sijens Paul E. , van der Hoorn Anouk
Published: August 2023

Isocitrate dehydrogenase (IDH) mutation status is an important biomarker in the glioma-defining subtype and corresponding prognosis. This study proposes a straightforward method for 2-hydroxyglutarate (2-HG) quantification by MR spectroscopy for IDH mutation status detection and directly compares in vivo 2-HG MR spectroscopy with ex vivo 2-HG concentration measured in resected tumor tissue. Eleven patients with suspected lower-grade glioma (ten IDH1; one IDHwt) were prospectively included. Preoperatively, 3T point-resolved spectroscopy (PRESS) was acquired; 2-HG was measured as the percentage elevation of Glx3 (the sum of 2-HG and Glx) compared to Glx4. IDH mutation status was assessed by immunochemistry or direct sequencing. The ex vivo 2-HG concentration was determined in surgically obtained tissue specimens using gas chromatography–mass spectrometry. Pearson correlation was used for assessing the correlation between in vivo MR spectroscopy and ex vivo 2-HG concentration. MR spectroscopy was positive for 2-HG in eight patients, all of whom had IDH1 tumors. A strong correlation (r = 0.80, p = 0.003) between 2-HG MR spectroscopy and the ex vivo 2-HG concentration was found. This study shows in vivo 2-HG MR spectroscopy can non-invasively determine IDH status in glioma and demonstrates a strong correlation with ex vivo 2-HG concentration in patients with lower-grade glioma.
Palatal Rugae as a Discriminating Factor in Determining Sex: A New Method Applicable in Forensic Odontology?
Authors: Trizzino Andrea , Messina Pietro , Sciarra Fabio Massimo , Zerbo Stefania , Argo Antonella , Scardina Giuseppe Alessandro
Published: August 2023

The purpose of this study is a new method that can help to identify the sex through the study of palatal rugae, comparing sagittal sections of the hard palate using Cartesian coordinates and evaluating the assistance given by digital technology and its applicability in this method. In this study, 57 digital impressions were examined and divided in two groups based on sex. Results: 2223 impression sections were studied and 145 coordinates that were present with a frequency greater than 50% in one or both groups were obtained: 52 discriminating traits (DT) in the male group, 29 discriminating traits in the female group, and 64 common traits (CT). The DTs in the female group showed no statistically significant difference from the same coordinates in the male one (p = 0.832). Statistically significant differences were observed in the DTs in the male group compared to the same coordinates in the female group (p = 0.018). No statistically significant differences were observed in the frequency of DTs in both sexes (p = 0.056). Further research in forensic odontology is needed to determine its scientific certainty. It is certain that digital technology may one day be a valuable support for the forensic odontologist but to date the lack of dedicated and certified programs limits its reliability.
Association between Salivary Cortisol Levels, Dental Anxiety, and Dental Caries in Children: A Cross-Sectional Study
Authors: Padmanabhan Vivek , Islam Md Sofiqul , Habib Muneera , Abdulaziz Zainab , Goud Manjunatha , Chaitanya Nallan CSK , Haridas Sheela , Rahman Muhammed Mustahsen
Published: August 2023

Aim: This study aimed to investigate the relationship between dental caries, dental anxiety, and salivary cortisol levels in children visiting pediatric dental clinics and their implications on pediatric oral health. Materials and Methods: A cross-sectional study was conducted at a dental university in the UAE. A total of 60 children, aged 4–12 years, were included. Salivary cortisol levels were measured using an Enzyme-Linked Immunosorbent Assay (ELISA) kit. Dental caries status was evaluated, and dental anxiety levels were assessed using the Modified Dental Anxiety Scale (MDAS). Statistical analyses, including Mann-Whitney U test and Pearson’s correlation coefficient, were performed to determine significant differences and associations. Results: The study group showed significantly higher salivary cortisol levels compared to the control group (p < 0.0001). A strong positive correlation was found between salivary cortisol levels and dental caries status (p < 0.001). However, no significant difference in dental anxiety levels was observed between the study and control groups (p = 0.85). A strong positive correlation was found between dental anxiety levels and dental caries status (p < 0.001). Conclusion: The findings indicate a significant association between salivary cortisol levels and dental caries, suggesting that higher cortisol levels are associated with active caries. Dental anxiety levels were positively correlated with dental caries. Understanding the relationship between these variables can contribute to better oral health strategies and interventions for children, emphasizing the importance of managing dental anxiety and stress in pediatric dental care. Clinical Significance: This study highlights the potential of salivary cortisol as a biomarker for assessing stress and its impact on oral health in children. By addressing dental anxiety and stress, dental professionals can provide child-friendly dental care, enhance preventive measures, and improve oral health outcomes in pediatric patients.
Reliability and Failure Mode of Ti-Base Abutments Supported by Narrow/Wide Implant Systems
Authors: Benalcázar-Jalkh Ernesto B. , de Carvalho Laura F. , Alves Larissa M. M. , Campos Tiago M. B. , Sousa Edisa de Oliveira , Bergamo Edmara T. P. , Coelho Paulo G. , Gierthmuehlen Petra C. , Spitznagel Frank A. , Zahoui Abbas , Bonfante Estevam A.
Published: August 2023

To assess the reliability and failure modes of Ti-base abutments supported by narrow and wide-diameter implant systems. Narrow (Ø3.5 × 10 mm) and wide (Ø5 × 10 mm) implant systems of two different manufacturers with internal conical connections (16°) and their respective Ti-base abutments (3.5 and 4.5 mm) were evaluated. Ti-base abutments were torqued to the implants, standardized metallic maxillary incisor crowns were cemented, and step stress accelerated life testing of eighteen assemblies per group was performed in three loading profiles: mild, moderate, and aggressive until fracture or suspension. Reliability for missions of 100,000 cycles at 100 and 150 N was calculated, and fractographic analysis was performed. For missions at 100 N for 100,000 cycles, both narrow and wide implant systems exhibited a high probability of survival (≥99%, CI: 94–100%) without significant differences. At 150 N, wide-diameter implants presented higher reliability (≥99%, CI: 99–100%) compared to narrow implants (86%, CI: 61–95%), with no significant differences among manufacturers. Failure mode predominantly involved Ti-base abutment fractures at the abutment platform. Ti-base abutments supported by narrow and wide implant systems presented high reliability for physiologic masticatory forces, whereas for high load-bearing applications, wide-diameter implants presented increased reliability. Failures were confined to abutment fractures.
The Impact of Core Complex Training on Some Basketball-Related Aspects of Physical Strength and Shooting Performance
Authors: Hassan Ahmed K. , Bursais Abdulmalek K. , Alibrahim Mohammed S. , Selim Hossam S. , Abdelwahab Ahmed M. , Hammad Badry E.
Published: August 2023

Exercises for the core can be categorized as promoting core-stability, core-strength, or functionality, as these are crucial aspects of most sports activities. This study aimed to examine the effects of using core complex training (CCT), complex training (CT), and core exercise (CE) on some aspects of muscle strength and shooting performance in basketball players. The 36 participants were divided into three groups of 12 each, and then the experimental approach was applied to each group. The groups were labeled as follows: the core complex training group (N = 12; age, 18.58 ± 0.67 years; height, 178.08 ± 0.79 cm; weight, 76.42 ± 1.38 kg; training age, 7.42 ± 0.51 years); the complex training group (N = 12; age, 18.50 ± 0.52 years; height, 177.92 ± 1.31 cm; weight, 76.67 ± 1.78 kg; training age, 7.33 ± 0.49 years); and the core exercise group (n = 12; age, 18.42 ± 0.52 years; height, 177.75 ± 1.29 cm; weight, 76.58 ± 1.38 kg; training age, 7.42 ± 0.67 years). For ten weeks, each of the three groups participated in three training sessions every week. This study investigates the impact of core complex training on basketball shooting ability and muscle strength. The eight-week program, consisting of weight training, plyometric exercises, and core exercises, yielded improvements in muscle strength and shooting accuracy. In tests of muscular strength and basketball shooting ability, the CCT group outperformed the CE and CT groups. The F value varied from 3.75 to 58.77, which are function values with a p < 0.05 significance level. The core complex training group exhibited superior muscle strength to that of both the complex training group and the core exercise group, in some areas. This is shown in the results of the javelin quadrathlon medicine ball test, the core muscle strength and stability test, the sit-up abdomen test, the sit-up back test, the standing long jump test, the Sargent jump test, and the shooting test (p < 0.005). Due to the effect of the core complex training program on improving performance efficiency and muscle strength, which affects the results of matches, we have recommended using the proven basic strength training program at other age stages, with the objective of including the concept, importance, and design of compound basic strength training in training programs used by basketball coaches.
Image Formation Algorithms for Low-Cost Freehand Ultrasound Scanner Based on Ego-Motion Estimation and Unsupervised Clustering
Authors: Abbas Ayusha , Neasham Jeffrey , Naqvi Mohsen
Published: August 2023

This paper describes the application of unsupervised learning techniques to improve ego-motion estimation for a low-cost freehand ultrasound probe. Echo decorrelation measurements, which are used to estimate the lateral velocity of a scanning probe as it is passed over the skin, are found to be sensitive to varying tissue types and echogenicity in the imaged scene, and this can impact the geometric accuracy of the generated images. Here, we investigate algorithms to cluster the collated 1D echo data into regions of different echogenicity by applying a Gaussian mixture model (GMM), spatial fuzzy c-means (SFCM) or k-means clustering techniques, after which the decorrelation measurements can focus on the regions that yield the most accurate velocity estimates. A specially designed mechanical rig is used to provide the ground truth for the quantitative analysis of probe position estimation on phantom and in vivo data using different clustering techniques. It is concluded that the GMM is the most effective in classifying regions of echo data, leading to the reconstruction of the most geometrically correct 2D B-mode ultrasound image.
Novel Neural-Network-Based Fuel Consumption Prediction Models Considering Vehicular Jerk
Authors: Zhang Licheng , Ya Jingtian , Xu Zhigang , Easa Said , Peng Kun , Xing Yuchen , Yang Ran
Published: August 2023

Conventional fuel consumption prediction (FCP) models using neural networks usually adopt driving parameters, such as speed and acceleration, as the training input, leading to a low prediction accuracy and a poor correlation between fuel consumption and driving behavior. To address this issue, the present study introduced jerk (an acceleration derivative) as an important variable in the training input of four selected neural networks: long short-term memory (LSTM), recurrent neural network (RNN), nonlinear auto-regressive model with exogenous inputs (NARX), and generalized regression neural network (GRNN). Furthermore, the root-mean-square error (RMSE), relative error (RE), and coefficient of determination (R2) were used to evaluate the prediction performance of each model. The results from the comparison experiment show that the LSTM model outperforms the other three models. Specifically, the four selected neural network models exhibited an improved accuracy in fuel consumption prediction after the jerk was added as a new variable to the training input. LSTM exhibited the greatest improvement under the high-speed expressway scenario, in which the RMSE decreased by 14.3%, the RE decreased by 28.3%, and the R2 increased by 9.7%.
A Ka-Band Doherty Power Amplifier in a 150 nm GaN-on-SiC Technology for 5G Applications
Authors: Parisi Alessandro , Papotto Giuseppe , Nocera Claudio , Castorina Alessandro , Palmisano Giuseppe
Published: August 2023

This paper presents a Ka-band three-stage power amplifier for 5G communications, which has been implemented in a 150 nm GaN-on-SiC technology and adopts a Doherty architecture. The amplifier is made up of a 50 Ω input buffer, which drives a power splitter, thanks to which it delivers its output power to the two power amplifier units of the Doherty topology, namely the main and auxiliary amplifier. Finally, the outputs of the two power amplifiers are properly arranged in a current combining scheme that enables the typical load modulation of the Doherty architecture, alongside allowing power combining at the final output. The proposed amplifier achieves a small signal gain of around 30 dB at 27 GHz, while providing a saturated output power of 32 dBm, with a power-added efficiency (PAE) as high as 26% and 18% at peak and 6 dB output power back-off, respectively.
Development of a Hybrid Method for Multi-Stage End-to-End Recognition of Grocery Products in Shelf Images
Authors: Melek Ceren Gulra , Battini Sonmez Elena , Ayral Hakan , Varli Songul
Published: August 2023

Product recognition on grocery shelf images is a compelling task of object detection because of the similarity between products, the presence of the different scale of product sizes, and the high number of classes, in addition to constantly renewed packaging and added new products’ difficulty in data collection. The use of conventional methods alone is not enough to solve a number of retail problems such as planogram compliance, stock tracking on shelves, and customer support. The purpose of this study is to achieve significant results using the suggested multi-stage end-to-end process, including product detection, product classification, and refinement. The comparison of different methods is provided by a traditional computer vision approach, Aggregate Channel Features (ACF) and Single-Shot Detectors (SSD) are used in the product detection stage, and Speed-up Robust Features (SURF), Binary Robust Invariant Scalable Key points (BRISK), Oriented Features from Accelerated Segment Test (FAST), Rotated Binary Robust Independent Elementary Features (BRIEF) (ORB), and hybrids of these methods are used in the product classification stage. The experimental results used the entire Grocery Products dataset and its different subsets with a different number of products and images. The best performance was achieved with the use of SSD in the product detection stage and the hybrid use of SURF, BRISK, and ORB in the product classification stage, respectively. Additionally, the proposed approach performed comparably or better than existing models.
Forecasting of Solar and Wind Resources for Power Generation
Authors: Islam M. K. , Hassan N. M. S. , Rasul M. G. , Emami Kianoush , Chowdhury Ashfaque Ahmed
Published: August 2023

Solar and wind are now the fastest-growing power generation resources, being ecologically benign and economical. Solar and wind forecasts are significantly noteworthy for their accurate evaluation of renewable power generation and, eventually, their ability to provide profit to the power generation industry, power grid system and local customers. The present study has proposed a Prophet-model-based method to predict solar and wind resources in the Doomadgee area of Far North Queensland (FNQ), Australia. A SARIMA modelling approach is also implemented and compared with Prophet. The Prophet model produces comparatively less errors than SARIMA such as a root mean squared error (RMSE) of 0.284 and a mean absolute error (MAE) of 0.394 for solar, as well as a MAE of 0.427 and a RMSE of 0.527 for wind. So, it can be concluded that the Prophet model is efficient in terms of its better prediction and better fitting in comparison to SARIMA. In addition, the present study depicts how the selected region can meet energy demands using their local renewable resources, something that can potentially replace the present dirty and costly diesel power generation of the region.
Effects of Anhydrous and Hydrous Fusel Oil on Combustion and Emissions on a Heavy-Duty Compression-Ignition Engine
Authors: Gao Dongzhi , Ikram Mubasher , Geng Chao , Wu Yangyi , Li Xiaodan , Jin Chao , Zheng Zunqing , Li Mengliang , Liu Haifeng
Published: August 2023

The efficient application of oxygen-containing clean fuels in engines has always been a research focus. With the increase in ethanol production, the output of fusel as a co-product is also increasing. The application of fusel is also an effective way to lessen the consumption of fossil fuels. Therefore, the influences of fusel on performance and emissions were investigated in the current study on a six-cylinder heavy-duty compression-ignition engine and revolved around the WHSC test cycle. The three test fuels were diesel, F20NW (the volume proportion of anhydrous fusel is 20%, and the rest is pure diesel), and F20WW (the volume proportion of hydrous fusel is 20%). The addition of fusel improved BTE, reduced NOx and soot emissions, and thermal efficiency and emissions were further improved in combination with EGR optimization. In terms of WHSC, the improvement effect of hydrous fusel was the best. The equivalent fuel consumption, NOx, soot, and CO2 emissions of F20WW were reduced by 1.77%, 37.49%, 17.38%, and 1.32%, respectively, with the optimization of EGR compared with pure diesel. The addition of 20% hydrous fusel combined with the introduction of EGR can be directly applied to existing diesel engines and achieve a simultaneous reduction in fuel consumption and emissions.
Robust Predictive Current Control of PMSG Wind Turbines with Sensor Noise Suppression
Authors: Li Junda , Babayomi Oluleke , Zhang Zhenbin , Li Zhen
Published: August 2023

Model predictive control (MPC) is an efficient and multi-functional control scheme for synchronous permanent magnet generators (PMSGs). However, the effective management of traditional MPC depends on precise system models. Multiple uncertainties of permanent magnet flux, motor inductance, filter inductance and parameter measurement noise will limit MPC’s performance. The conventional linear extended state observer (ESO) can perform robust predictive control of the ultralocal model of the PMSG system to cope with parameter mismatches. However, the ESO is limited in balancing disturbance rejection with measurement noise attenuation. Since the amplification of high-frequency noise pollution can lead to both poor control performance and system instability, this challenge is of significant importance. To solve the problem, a new hybrid parallel cascaded ESO (PCESO) model-free predictive control framework is proposed using the three-level neutral-point-clamped (NPC) power electronic converter, on both the machine side and grid side. Analytical discussions of the time and frequency domain characteristics of the PCESO demonstrate its superior characteristics over the ESO. The proposed method can effectively balance parameter mismatch, disturbance rejection and high-frequency noise suppression. Finally, the effectiveness of the proposed method, under uncertainties of parameter mismatches, measurement noise and permanent magnet flux, is verified through real-time hardware-in-the-loop tests on a back-to-back grid-tied PMSG interfaced with an NPC power converter.
Numerical Investigation on Heat Transfer and Flow Resistance Characteristics of Superheater in Hydrocracking Heat Recovery Steam Generator
Authors: Zhang Danfeng , Wang Xin , Zhao Liang , Xie Huaqing , Guo Chen , Qian Feizhou , Dong Hui , Hu Yun
Published: August 2023

The heat recovery steam generator (HRSG) was utilized to recover the waste heat resources of the catalyst’s regenerated gas with the objective to reduce the energy consumption of the hydrocracking process. In this study, the flow resistance and heat transfer performance of the superheater tube bundles in the hydrocracking HRSG were investigated via numerical simulation. The performance evaluation criterion (PEC1) was applied to characterize the comprehensive heat transfer performance of superheater tube bundles. The results showed that as the transverse tube pitch increased, the Nusselt number (Nu) showed a monotonically increasing trend, the Euler number (Eu) showed a monotonically decreasing trend, and PEC1 showed a monotonically increasing trend. As the longitudinal tube pitch increased, Nu exhibited a monotonically increasing trend, Eu showed a monotonically decreasing trend, and PEC1 showed a monotonically increasing trend. In the scope of the simulated results, as the transverse and longitudinal tube pitches were 110 mm and 95 mm, respectively, PEC1 reached the maximum value. Compared with the primary structural parameters, PEC1 increased by 2.32% and 8.50%, respectively. Finally, a new correlation was proposed to predict Nu and Eu of the superheater tube bundles in the hydrocracking HRSG.
An Improved Power-Sharing Method for a Multi-Terminal HVDC Transmission System Based on Adaptive Voltage Droop Control
Authors: Jing Liuming , Wei Jiahe , Xia Lei , Fan Zhaolin , Zhou Jinghua
Published: August 2023

The prerequisite for the normal operation of a flexible high-voltage direct current (HVDC) transmission system is the maintenance of the stability of the direct current (DC)-side voltage, and droop control has a good dynamic regulation capability. In this paper, we first study the operating characteristics of droop control and derive its equivalent circuit, as well as the power distribution equation for droop control with a four-terminal system as an example. Then, based on this, an improved droop control method is proposed so that the droop factor can be adaptively adjusted according to the power change and provide corresponding characteristics under different operating conditions to enhance the power regulation capability of the controller under high power fluctuations. Finally, a power systems computer-aided design (PSCAD) electromagnetic transient model of the four-terminal, flexible, high-voltage DC transmission system was established and verified by simulation results.
Trends, Projections, and Regional Disparities of Maternal Mortality in Africa (1990–2030): An ARIMA Forecasting Approach
Authors: Onambele Luc , Guillen-Aguinaga Sara , Guillen-Aguinaga Laura , Ortega-Leon Wilfrido , Montejo Rocio , Alas-Brun Rosa , Aguinaga-Ontoso Enrique , Aguinaga-Ontoso Ines , Guillen-Grima Francisco
Published: August 2023

With the United Nations Sustainable Development Goals (SDG) (2015–2030) focused on the reduction in maternal mortality, monitoring and forecasting maternal mortality rates (MMRs) in regions like Africa is crucial for health strategy planning by policymakers, international organizations, and NGOs. We collected maternal mortality rates per 100,000 births from the World Bank database between 1990 and 2015. Joinpoint regression was applied to assess trends, and the autoregressive integrated moving average (ARIMA) model was used on 1990–2015 data to forecast the MMRs for the next 15 years. We also used the Holt method and the machine-learning Prophet Forecasting Model. The study found a decline in MMRs in Africa with an average annual percentage change (APC) of −2.6% (95% CI −2.7; −2.5). North Africa reported the lowest MMR, while East Africa experienced the sharpest decline. The region-specific ARIMA models predict that the maternal mortality rate (MMR) in 2030 will vary across regions, ranging from 161 deaths per 100,000 births in North Africa to 302 deaths per 100,000 births in Central Africa, averaging 182 per 100,000 births for the continent. Despite the observed decreasing trend in maternal mortality rate (MMR), the MMR in Africa remains relatively high. The results indicate that MMR in Africa will continue to decrease by 2030. However, no region of Africa will likely reach the SDG target.
Exploring Anaerobic Digestion from Mesophilic to Thermophilic Temperatures—Operational and Microbial Aspects
Authors: Steiniger Bettina , Hupfauf Sebastian , Insam Heribert , Schaum Christian
Published: August 2023

Digesters at water resource recovery facilities (WRRFs) operating at different temperatures within the mesophilic and thermophilic temperature range is a flexibilization concept to contribute to heat management. Four 25 L digesters were fed with sewage sludge from a municipal WRRF and were operated at 37, 43, 47 and 53 °C, respectively, to describe changes in the overall process performance and the microbiota. Specific methane yield and COD degradation rates were the highest at 47 °C, only being up to 7% higher compared with at 37 °C. The increase in pH and concentrations of NH4-N and PO4-P above 43 °C were statistically significant. The effect on the microbial community was strong, indicating both a constant specialization towards thermophilic organisms as well as a change from acetoclastic to hydrogenotrophic/methylotrophic methanogenesis. The influence of temperature on process-engineering and physicochemical aspects was rather small compared with the changes in the microbiota.
Use of Bio-Waste of Ilex paraguariensis A. St. Hil. (Yerba mate) to Obtain an Extract Rich in Phenolic Compounds with Preservative Potential
Authors: Menezes Bárbara , Caleja Cristina , Calhelha Ricardo C. , Pinela José , Dias Maria Inês , Stojković Dejan , Soković Marina , Gonçalves Odinei Hess , Leimann Fernanda Vitória , Pereira Eliana , Barros Lillian
Published: August 2023

In this work, a comparison between the extracts of dehydrated yerba mate (Ilex paraguariensis) and bio-waste of yerba mate leaves from the Brazilian industry was made. The incorporation of the functional extract as a preservative/functional ingredient in a pastry product (pancakes) was tested. The individual profile of phenolic compounds was determined by HPLC-DAD-ESI/MS, and the bioactive potential was assessed using in vitro assays for antioxidant, anti-inflammatory, antimicrobial, and cytotoxic activities. The yerba mate extracts revealed a high antimicrobial potential against the tested strains and a very promising antioxidant and anti-inflammatory action. Additionally, revealed a cytotoxic capacity for MCF-7, CaCo and AGS tumor cell-lines. In the three types of pancakes, after 3 days of storage, the chemical and nutritional characteristics remain unchanged, proving the preservative efficiency of the extract. This study showed the benefits of the use bio-waste from agro-industrial sector, focusing on sustainable production and the development of circular economy.