bluuebunny/crossref_metadata_2025 huggingface dataset:
Exome Profiling Suggests Combined Effect of Myeloperoxidase, Toll-Like Receptors, and Metallopeptidase in Hidradenitis Suppurativa
Authors: Azzarà Alessia , Cassano Ilaria , Lintas Carla , Gurrieri Fiorella
Published: October 2024

Background: Hidradenitis suppurativa, also called acne inversa, is a chronic skin inflammatory condition involving hair follicles, sebaceous glands, and apocrine glands. Symptoms can be variable in intensity, ranging from mild to severe. The exact causes of hidradenitis suppurativa are not fully understood, but the etiology is presumed to be multifactorial, encompassing genetics and environmental factors. Methods: Two families presented with hidradenitis suppurativa with an autosomal dominant pattern. We performed whole-exome sequencing in two unrelated patients from the two families. Results: We identified two and three variants in the two families, respectively. Variants involved the TLR2 and MPO genes in the first family and the MMP2, GJB2, and TLR4 genes, some of which have already been previously reported as possible candidates for hidradenitis suppurativa. Conclusion: It is very likely that variants in a single gene only rarely cause the condition and that most cases, especially familial hidradenitis suppurativa cases, may more probably take the form of polygenic disorders.
Tumor-Associated Tractography Derived from High-Angular-Resolution Q-Space MRI May Predict Patterns of Cellular Invasion in Glioblastoma
Authors: Leary Owen P. , Zepecki John P. , Pizzagalli Mattia , Toms Steven A. , Liu David D. , Suita Yusuke , Ding Yao , Wang Jihong , He Renjie , Chung Caroline , Fuller Clifton D. , Boxerman Jerrold L. , Tapinos Nikos , Gilbert Richard J.
Published: October 2024

Background: The invasion of glioblastoma cells beyond the visible tumor margin depicted by conventional neuroimaging is believed to mediate recurrence and predict poor survival. Radiomic biomarkers that are associated with the direction and extent of tumor infiltration are, however, non-existent. Methods: Patients from a single center with newly diagnosed glioblastoma (n = 7) underwent preoperative Q-space magnetic resonance imaging (QSI; 3T, 64 gradient directions, b = 1000 s/mm2) between 2018 and 2019. Tumors were manually segmented, and patterns of inter-voxel coherence spatially intersecting each segmentation were generated to represent tumor-associated tractography. One patient additionally underwent regional biopsy of diffusion tract- versus non-tract-associated tissue during tumor resection for RNA sequencing. Imaging data from this cohort were compared with a historical cohort of n = 66 glioblastoma patients who underwent similar QSI scans. Associations of tractography-derived metrics with survival were assessed using t-tests, linear regression, and Kaplan–Meier statistics. Patient-derived glioblastoma xenograft (PDX) mice generated with the sub-hippocampal injection of human-derived glioblastoma stem cells (GSCs) were scanned under high-field conditions (QSI, 7T, 512 gradient directions), and tumor-associated tractography was compared with the 3D microscopic reconstruction of immunostained GSCs. Results: In the principal enrollment cohort of patients with glioblastoma, all cases displayed tractography patterns with tumor-intersecting tract bundles extending into brain parenchyma, a phenotype which was reproduced in PDX mice as well as in a larger comparison cohort of glioblastoma patients (n = 66), when applying similar methods. Reconstructed spatial patterns of GSCs in PDX mice closely mirrored tumor-associated tractography. On a Kaplan–Meier survival analysis of n = 66 patients, the calculated intra-tumoral mean diffusivity predicted the overall survival (p = 0.037), as did tractography-associated features including mean tract length (p = 0.039) and mean projecting tract length (p = 0.022). The RNA sequencing of human tissue samples (n = 13 tumor samples from a single patient) revealed the overexpression of transcripts which regulate cell motility in tract-associated samples. Conclusions: QSI discriminates tumor-specific patterns of inter-voxel coherence believed to represent white matter pathways which may be susceptible to glioblastoma invasion. These findings may lay the groundwork for future work on therapeutic targeting, patient stratification, and prognosis in glioblastoma.
The Role of the Microbiome and of Radiotherapy-Derived Metabolites in Breast Cancer
Authors: Herrera-Quintana Lourdes , Vázquez-Lorente Héctor , Silva Rafael Cardoso Maciel Costa , Olivares-Arancibia Jorge , Reyes-Amigo Tomás , Pires Bruno Ricardo Barreto , Plaza-Diaz Julio
Published: October 2024

The gut microbiome has emerged as a crucial player in modulating cancer therapies, including radiotherapy. In the case of breast cancer, the interplay between the microbiome and radiotherapy-derived metabolites may enhance therapeutic outcomes and minimize adverse effects. In this review, we explore the bidirectional relationship between the gut microbiome and breast cancer. We explain how gut microbiome composition influences cancer progression and treatment response, and how breast cancer and its treatments influence microbiome composition. A dual role for radiotherapy-derived metabolites is explored in this article, highlighting both their therapeutic benefits and potential hazards. By integrating genomics, metabolomics, and bioinformatics tools, we present a comprehensive overview of these interactions. The study provides real-world insight through case studies and clinical trials, while therapeutic innovations such as probiotics, and dietary interventions are examined for their potential to modulate the microbiome and enhance treatment effectiveness. Moreover, ethical considerations and patient perspectives are discussed, ensuring a comprehensive understanding of the subject. Towards revolutionizing treatment strategies and improving patient outcomes, the review concludes with future research directions. It also envisions integrating microbiome and metabolite research into personalized breast cancer therapy.
Tumor Response and Its Impact on Treatment Failure in Rectal Cancer: Does Intensity of Neoadjuvant Treatment Matter?
Authors: Diefenhardt Markus , Martin Daniel , Fleischmann Maximilian , Hofheinz Ralf-Dieter , Ghadimi Michael , Rödel Claus , Fokas Emmanouil
Published: October 2024

Objectives: Additional adjuvant treatment in patients with rectal cancer with limited response to neoadjuvant treatment to mitigate their higher risk of treatment failure remains controversial. Methods: This is a post hoc analysis of a cohort study of 3 randomized phase 2 or 3 trials (CAO/ARO/AIO-94, -04, and -12 trial) that included 1948 patients with locally advanced rectal adenocarcinoma. After excluding patients with missing information, 1788 patients (1254 men and 524 women; median age: 62.6 years, age range: 19–84 years) were eligible. We analyzed the extent of tumor response and its association with the incidence of treatment failure after different neoadjuvant treatment approaches. Results: Tumor response was significantly enhanced with more intensive neoadjuvant treatment. After a median follow-up of 55 months for the entire cohort (IQR: 37 months–62 months), the incidence of treatment failure (TF) stratified by tumor response or post-neoadjuvant pathological outcome was not significantly affected by the intensity of neoadjuvant treatment, whereas the ypTNM stage was significantly associated with the risk of treatment failure. Conclusions: In this cohort study, we provide evidence that limited or no response to intensified neoadjuvant treatment protocols is not likely to be more strongly associated with an extensive risk of TF after 5-FU CRT+/− adjuvant chemotherapy.
Analysis of Predictive Factors Associated with Unsuccessful Sentinel Lymph Node Mapping in Endometrial Carcinoma
Authors: Andreika Linas , Šiaudinytė Monika , Vankevičienė Karolina , Ramašauskaitė Diana , Rudaitis Vilius
Published: October 2024

Background: Sentinel lymph node (SLN) biopsy is recommended over systematic lymphadenectomy in early-stage endometrial cancer due to its lower morbidity and comparable detection rate. The objective of this study was to identify clinical factors associated with unsuccessful mapping. Methods: Between April 2020 and June 2024, 120 patients over the age of 18 and diagnosed with early-stage endometrial cancer were enrolled in this prospective study at a single institution. Demographic, clinicopathologic, and treatment data were collected and analyzed using descriptive statistics. Univariate and multiple linear regressions were performed to identify predictors of failed mapping. Results: The mean age of the patient cohort was 62.5 years (range 33 to 83), and the mean body mass index (BMI) was 32 kg/m2 (range 18 to 50). Patients underwent intracervical injections with methylene blue (MB), indocyanine green (ICG), or a combination of both tracers, with 40 patients in each group. A total of 108 patients (90.0%) were diagnosed with endometrioid carcinoma and 12 (10.0%) with non-endometrioid cancers. Additionally, 110 patients (91.7%) were diagnosed in early stages of the disease. The overall SLN detection rate was 73.4%, with bilateral detection at 49.2% and unilateral detection at 24.2%. Univariate analysis showed that older age (p < 0.001), menopause (p = 0.001), the use of MB as the sole tracer (p = 0.006), a shorter tumor-to-serosa distance (p = 0.048), and bulky lymph nodes (p = 0.18) were associated with unsuccessful mapping. Multiple linear regression model analysis identified age (p = 0.007), tracer type (p = 0.013), and enlarged lymph nodes (p = 0.013) as independent predictors of SLN mapping failure. Conclusions: Advanced age, tracer type, and intraoperative detection of enlarged lymph nodes were identified as independent risk factors for unsuccessful mapping in patients undergoing laparoscopic SLN mapping.
Prognostic Value of Neutrophil-to-Eosinophil Ratio (NER) in Cancer: A Systematic Review and Meta-Analysis
Authors: Sahin Taha Koray , Ayasun Ruveyda , Rizzo Alessandro , Guven Deniz Can
Published: October 2024

Background: The identification of reliable prognostic biomarkers is crucial for optimizing cancer treatment strategies, especially in the era of personalized medicine. This systematic review and meta-analysis evaluate the prognostic significance of the neutrophil-to-eosinophil ratio (NER) in various cancer types, with a focus on its association with overall survival (OS) and progression-free survival (PFS). Methods: We conducted a systematic literature search across PubMed, Scopus, and Web of Science databases for studies published up to 28 July 2024. We performed the meta-analyses with the generic inverse variance method with a random effects model and reported hazard ratios (HR) with 95% confidence intervals (CI). Results: The comprehensive literature search identified 10 studies comprising 2351 patients. Pooled analyses demonstrated that elevated pretreatment NER levels were significantly correlated with poorer OS (HR: 1.74, 95% CI: 1.28–2.36, p < 0.001) and PFS (HR: 1.53, 95% CI: 1.21–1.95, p < 0.001). Subgroup analyses confirmed a consistent adverse association between high NER and OS across various tumor types and geographic locations, although results from studies conducted in the Far East did not reach statistical significance. Conclusions: This meta-analysis demonstrates that elevated NER is associated with poorer OS and PFS in cancer patients, suggesting its potential utility as a non-invasive prognostic marker. Further validation in large, prospective studies is warranted to establish NER’s role in guiding personalized treatment strategies across diverse oncologic contexts.
Color Stability of Bulk-Fill Flowable Resin Composites After Artificial Aging
Authors: Floriani Franciele , Jurado Carlos A. , Madhu Nikkita , Lackey Mark A. , Azpiazu-Flores Francisco X. , Lopes Guilherme Carpena
Published: October 2024

Background: This study aimed to evaluate the color stability of bulk-fill flowable resin composites with 2 difference shades at baseline and after artificial aging. Methods: Disk-shaped specimens (Ø10 × 4 mm) were fabricated from three bulk-fill flowable resin resin composites (Filtek Bulk-Fill Flow, Venus Bulk-Fill Flow, and Estelite Bulk-Fill Flow). The specimens in each bulk-fill resin composite group were divided into two subgroups (n = 10 per subgroup) with two different shades, A1 (N = 30) and A3 (N = 30), and were polymerized with light curing (800 mW/cm2/Valo LED Unit, Ultradent) and polished. The color difference between bulk-fill resin composites was evaluated at baseline and after artificial aging using a spectrophotometer (CM-700d, Konica Minolta, Tokyo, Japan) under D65 illumination. Color coordinates were measured with CIEDE2000, and color differences (∆E00) and relative translucency parameter (RTP) values were calculated. Subsequently, the comparison of color changes (∆E00) before and after thermocycling was performed using the t-test for paired samples. Results: The bulk-fill flow resin composites evaluated in the present study were capable of mimicking important optical properties such as light transmission. All the resin composites provided acceptable color stability at baseline and after thermocycling when the color A1 was used. On the other hand, whenever the shade A3 was used, the Venus Bulk-Fill Flow demonstrated the best optical properties. There was no statistically significant difference when comparing baseline and after thermocycling in bulk-fill flowable resin composites (p > 0.05). After thermocycling, A1 bulk-fill flowable resin composites provided acceptable color stability, and all A3 bulk-fill flowable resin composites provided visible color change, except for the Venus Bulk-Fill Flow (∆E00 = 2.35). Conclusions: Estelite Bulk-Fill Flow displayed the best color stability (∆E00 = 2.22) between all the combinations evaluated.
Comprehensive Theoretical Formulation and Numerical Simulation of the Internal Flow in Pressure-Swirl Atomizers Type Screw-Conveyer
Authors: Ronceros Julio , Raymundo Carlos , Zapata Gianpierre , Namay Wilder , Ronceros Gustavo
Published: October 2024

The present work shows the development of a comprehensive theoretical formulation for its application in the study of the internal flow of pressure-swirl atomizers with helical channels: “screw-conveyer”, which are characterized by presenting in their inlet channels, an angle of incidence or helix angle ψ. This angle originates a trigonometric factor (cosψ) that must be considered in the geometrical characteristics parameter of pressure-swirl atomizer (Ah), which consequently involves other geometric parameters, such as the annular section coefficient (φ), discharge coefficient (Cd), spray angle (2α), etc., being relevant in the internal flow study and design of the pressure-swirl atomizers type screw-conveyer. This theoretical formulation integrates an internal ideal flow model (Abramovich theory) with a model that considers the influence of the liquid viscosity (Kliachko theory) and hydraulic resistance of Idelchik. For the validation of this theoretical formulation, numerical simulation was used, considering the commercial software Ansys Fluent 2023 R2 furthermore, hexahedral meshes were generated with the ICEM CFD software 2023, for four cases of helix angle ψ (15°, 30°, 45° and 60°), with application of the RNG k-ε turbulence model and VOF multiphase model (volume of fluid) for the location of the liquid-gas interface and spray angle visualization.
Analyze the Temporal and Spatial Distribution of Carbon Capture in Sustainable Development of Work
Authors: Chen Fu-Hsuan , Liu Hao-Ren
Published: October 2024

This study aims to analyze the temporal and spatial distribution of carbon capture technologies worldwide, examining the economic, social, and political developments reflected in related academic literature. By conducting a comprehensive analysis of over 40,000 related documents from 2004 to June 2024, as well as selecting 108 relevant articles from SSCI and SCI journals, the study explores the development of carbon capture technologies from different perspectives through keyword searches, trend analysis, and relevance ranking. The study finds that, in terms of temporal trends, significant progress has been made in carbon capture technologies since 2009, and their importance has surpassed that of carbon trading, becoming one of the core technologies in addressing climate change. Spatial trend analysis shows that North American and European countries are more inclined to prioritize “carbon capture” technologies, while Asian countries focus more on “carbon trading”, reflecting regional differences in economic, policy, and technological development. Although carbon capture technologies hold immense potential for sustainable development, they also face numerous challenges, including balancing technological advancements with economic and policy frameworks. This balance is crucial to ensuring that carbon capture technologies can make a positive contribution to sustainable work, climate action, and environmental sustainability, further transforming the essence of sustainable efforts. To fully realize their benefits, it is essential to recognize and address these challenges.
Hydrogen Yield Enhancement in Biogas Dry Reforming with a Ni/Cr Catalyst: A Numerical Study
Authors: Nishimura Akira , Yamada Souta , Ichii Ryoma , Ichikawa Mizuki , Hayakawa Taisei , Kolhe Mohan Lal
Published: October 2024

This numerical study investigates the impact of the reaction temperature, molar ratio of CH4:CO2, and catalyst porosity (εp) on the H2 yield and H2 selectivity during biogas dry reforming over a Ni/Cr catalyst. Using COMSOL Multiphysics, we conducted detailed simulations to elucidate the underlying reaction characteristics. Our findings reveal that increasing εp from 0.1 to 0.95 significantly provides a 5 times increase in H2 production and a 2.3% increase in H2 selectivity while simultaneously reducing CO selectivity by 2.3%. This effect is attributed to the improved mass transfer within the catalyst bed, leading to more efficient reactant conversion and product formation. Additionally, we observed a strong correlation between higher reaction temperatures and increased H2 yield and H2 selectivity. By optimizing these operational parameters, our results suggest that Ni/Cr catalysts can be effectively employed for the sustainable production of H2 from biogas.
Multimodal Operation Data Mining for Grid Operation Violation Risk Prediction
Authors: Meng Lingwen , Zhong Jingliang , Luo Shasha , Zhu Xinshan , Wang Yulin , Zhang Shumei
Published: October 2024

With the continuous expansion of the power grid, the issue of operational safety has attracted increasing attention. In power grid operation control, unauthorized operations are one of the primary causes of personal accidents. Therefore, preventing and monitoring unauthorized actions by power grid operators is of critical importance. First, multimodal violation data are integrated through information systems, such as the power grid management platform, to construct a historical case database. Next, word vectors for three types of operation-related factors are generated using natural language processing techniques, and key vectors are selected based on generalized correlation coefficients using mutual information, enabling effective dimensionality reduction. Independent component analysis is then employed for feature extraction and further dimensionality reduction, allowing for the effective characterization of operational scenarios. For each historical case, a risk score is derived from a violation risk prediction model constructed using the Random Forests (RF) algorithm. When a high-risk score is identified, the K-Nearest Neighbor (KNN) algorithm is applied to locate similar scenarios in the historical case database where violations may have occurred. Real-time violation risk assessment is performed for each operation, providing early warnings to operators, thereby reducing the likelihood of violations, and enhancing the safety of power grid operations.
Two-Stage Optimal Scheduling Strategy of Microgrid Distribution Network Considering Multi-Source Agricultural Load Aggregation
Authors: Ma Guozhen , Pang Ning , Wang Yunjia , Hu Shiyao , Xu Xiaobin , Zhang Zeya , Wang Changhong , Gao Liai
Published: October 2024

With the proposed “double carbon” target for the power system, large-scale distributed energy access poses a major challenge to the way the distribution grid operates. The rural distribution network (DN) will transform into a new local power system primarily driven by distributed renewable energy sources and energy storage, while also being interconnected with the larger power grid. The development of the rural DN will heavily rely on the construction and efficient planning of the microgrid (MG) within the agricultural park. Based on this, this paper proposes a two-stage optimal scheduling model and solution strategy for the microgrid distribution network with multi-source agricultural load aggregation. First, in the first stage, considering the flexible agricultural load and the market time-of-use electricity price, the economic optimization is realized by optimizing the operation of the schedulable resources of the park. The linear model in this stage is solved by the Lingo algorithm with fast solution speed and high accuracy. In the second stage, the power interaction between the MG and the DN in the agricultural park is considered. By optimising the output of the reactive power compensation device, the operating state of the DN is optimised. At this stage, the non-linear and convex optimization problems are solved by the particle swarm optimization algorithm. Finally, the example analysis shows that the proposed method can effectively improve the feasible region of safe operation of the distribution network in rural areas and improve the operating income of a multi-source agricultural load aggregation agricultural park.
Integrating Metal–Organic Frameworks and Polyamide 12 for Advanced Hydrogen Storage Through Powder Bed Fusion
Authors: Shang Chengming , Liu Yaan , Ghita Oana , Lachman Noa , Wang Dong , Tian Mi
Published: October 2024

This paper introduces a pioneering approach that combines ex situ synthesis with advanced manufacturing to develop ZIF-67-PA12 Nylon composites with mixed-matrix membranes (MMMs), with the goal of enhancing hydrogen storage systems. One method involves producing MOF-PA12 composite powders through an in situ process, which is then commonly used as a base powder for powder bed fusion (PBF) to fabricate various structures. However, developing the in situ MOF-PA12 matrix presents challenges, including limited spreadability and processability at higher MOF contents, as well as reduced porosity due to pore blockage by polymers, ultimately diminishing hydrogen storage capacity. To overcome these issues, PBF is employed to form PA12 powder into films, followed by the ex situ direct synthesis of ZIF-67 onto these substrates at loadings exceeding those typically used in conventional MMM composites. In this study, ZIF-67 mass loadings ranging from 2 to 30 wt.% were synthesized on both PA12 powder and printed film substrates, with loadings on printed PA12 films extended up to 60 wt.%. ZIF-67-PA12-60(f) demonstrated a hydrogen capacity of 0.56 wt.% and achieved 1.53 wt.% for ZIF-67-PA12-30(p); in comparison, PA12 exhibited a capacity of 0.38 wt.%. This was undertaken to explore a range of ZIF-67 Metal–organic frameworks (MOFs) to assess their impact on the properties of the composite, particularly for hydrogen storage applications. Our results demonstrate that ex situ-synthesized ZIF-67-PA12 composite MMMs, which can be used as a final product for direct application and do not require the use of in situ pre-synthesized powder for the PBF process, not only retain significant hydrogen storage capacities, but also offer advantages in terms of repeatability, cost-efficiency, and ease of production. These findings highlight the potential of this innovative composite material as a practical and efficient solution for hydrogen storage, paving the way for advancements in energy storage technologies.
Enhancing Regional Wind Power Forecasting through Advanced Machine-Learning and Feature-Selection Techniques
Authors: Taheri Nabi , Tucci Mauro
Published: October 2024

In this study, an in-depth analysis is presented on forecasting aggregated wind power production at the regional level, using advanced Machine-Learning (ML) techniques and feature-selection methods. The main problem consists of selecting the wind speed measuring points within a large region, as the wind plant locations are assumed to be unknown. For this purpose, the main cities (province capitals) are considered as possible features and four feature-selection methods are explored: Pearson correlation, Spearman correlation, mutual information, and Chi-squared test with Fisher score. The results demonstrate that proper feature selection significantly improves prediction performance, particularly when dealing with high-dimensional data and regional forecasting challenges. Additionally, the performance of five prominent machine-learning models is analyzed: Long Short-Term Memory (LSTM) networks, Artificial Neural Networks (ANNs), Support Vector Machines (SVMs), Convolutional Neural Networks (CNNs), and Extreme-Learning Machines (ELMs). Through rigorous testing, LSTM is identified as the most effective model for the case study in northern Italy. This study offers valuable insights into optimizing wind power forecasting models and underscores the importance of feature selection in achieving reliable and accurate predictions.
Computational Methods for Verifying the Normative Requirements Regarding the Lateral Correction Force of a Powered Roof Support
Authors: Szweda Stanisław , Szyguła Marek , Szelka Michał , Banaś Marian , Kołodziejczyk Krzysztof
Published: October 2024

The article discusses laboratory methods and the corresponding computational methods verifying compliance with the normative requirements regarding the lateral correction force of the powered roof support. The currently used flat model only allows for checking the normative requirement in relation to the sum of active forces of the correction cylinders installed in the roof support. Determining the required value of the active force of each cylinder is possible due to the simplified FEM model of a powered roof support, described in the research work, treated as a uniform weightless elastic body loaded with a concentrated force recreating the weight of the roof support located on an inclined longwall panel. The third analysed computational method involves determining the reaction in the four correction cylinders of the roof support, creating a spatial, statically indeterminate system of forces. It enables determining the range of variability of the response in the correction cylinders as a function of the distribution of floor pressure on the roof support base. The discussed computational methods were used to determine, for example, the lateral correction force of one of the types of powered supports used in a longwall panel inclined at an angle of 35°. The usefulness of the discussed calculation methods at various stages of the designing process of the powered support and its certification has been confirmed.
Optimal Configuration of Electricity-Heat Integrated Energy Storage Supplier and Multi-Microgrid System Scheduling Strategy Considering Demand Response
Authors: Liu Yuchen , Dou Zhenhai , Wang Zheng , Guo Jiaming , Zhao Jingwei , Yin Wenliang
Published: October 2024

Shared energy storage system provides an attractive solution to the high configuration cost and low utilization rate of multi-microgrid energy storage system. In this paper, an electricity-heat integrated energy storage supplier (EHIESS) containing electricity and heat storage devices is proposed to provide shared energy storage services for multi-microgrid system in order to realize mutual profits for different subjects. To this end, electric boiler (EB) is introduced into EHIESS to realize the electricity-heat coupling of EHIESS and improve the energy utilization rate of electricity and heat storage equipment. Secondly, due to the problem of the uncertainty in user-side operation of multi-microgrid system, a price-based demand response (DR) mechanism is proposed to further optimize the resource allocation of shared electricity and heat energy storage devices. On this basis, a bi-level optimization model considering the capacity configuration of EHIESS and the optimal scheduling of multi-microgrid system is proposed, with the objectives of maximizing the profits of energy storage suppliers in upper-level and minimizing the operation costs of the multi-microgrid system in lower-level, and solved based on the Karush-Kuhn-Tucker (KKT) condition and Big-M method. The simulation results show that in case of demand response, the total operation cost of multi-microgrid system and the total operation profit of EHIESS are 51,687.73 and 11,983.88 CNY, respectively; and the corresponding electricity storage unit capacity is 9730.80 kWh. The proposed model realizes the mutual profits of EHIESS and multi-microgrid system.
Comparative Numerical and Experimental Analyses of Conical Solar Collector and Spot Fresnel Concentrator
Authors: Alsalame Haedr Abdalha Mahmood , Sik Kang Kyeong , Lee Gwi Hyun
Published: October 2024

This paper aims to compare the thermal performances of the conical solar collector (CSC) system and the spot Fresnel lens system (SFL) using water and CuO nanofluid as the working fluids. The studied CFD models for both systems were validated using experimental data. At an optimal flow rate of 6 L/min, the SFL system showed higher optical and thermal performance in comparison with that of the CSC system. In the case of the SFL system, the availability of a greater amount of solar energy per unit collector area caused an increase in thermal energy. Moreover, in the case of the CSC system, the non-uniform distribution of solar flux on the absorber’s outer surface leads to an increase in temperature gradient and heat losses. As a heating medium, the CuO nanofluid outperformed the water in terms of higher thermal conductivity and heat capacity. The average thermal efficiencies of 64.7% and 61.2% were achieved using SFL with and without CuO nanofluid, respectively, which were 2.4% and 0.5% higher than those of the CSC with and without nanofluid. CFD simulations show a 2.80% deviation for SFL and 2.92% for CSC, indicating acceptable accuracy compared to experimental data.
Study on Coal Pillar Setting and Stability in Downward Mining Section of Close Distance Coal Seam
Authors: Ma Longpei , Liu Chongyan , Zhao Guangming
Published: October 2024

To investigate the reasonable width of a coal pillar in the downward mining section of close-distance coal seams, the stress state of any point below the residual coal pillar in the overlying goaf and the width of a small coal pillar were studied by theoretical calculation, numerical simulation, similar simulation and field monitoring. The findings indicate that the width range of the small coal pillar is 7.92~11.42 m. The 4-1 coal seam is in the stress reduction zone when it is more than 16.6 m horizontally from the border of the residual coal pillar above it. In addition, the peak stress is situated inside the elastic zone of the coal pillar and is lower than the coal pillar’s bearing limit when a small coal pillar of 8 m is maintained. With the help of distributed optical fiber monitoring to model the coal pillars’ stress distribution, it is found that 8 m simulated coal pillars have a certain bearing capacity. The practical findings demonstrate that the 8 m small coal pillar that was left on the site satisfies the demand, and the convergence of the roadway’s floor and roof, and its two sides fall within the controllable range. The findings of the study offer a reference for the location of a return air roadway and the width of section coal pillars in the downward mining of close-distance coal seams.
Waste-to-Energy Conversion of Rubberwood Residues for Enhanced Biomass Fuels: Process Optimization and Eco-Efficiency Evaluation
Authors: Kasawapat Jannisa , Khamwichit Attaso , Dechapanya Wipawee
Published: October 2024

Torrefaction was applied to enhance the fuel properties of sawdust (SD) and bark wood (BW), biomass wastes from the rubberwood processing industry. Design Expert (DE) software was used in an experimental design to study the effects of affecting factors including torrefaction temperature and time as well as the biomass size towards the desirable properties such as HHV, mass yield, fixed carbon content, and eco-efficiency values. Promising results showed that the HHVs of the torrefied SD (25 MJ/kg) and BW (26 MJ/kg) were significantly increased when compared to preheated SD (17 MJ/kg) and preheated BW (17 MJ/kg) and in a range similar to that of coal (25–35 MJ/kg). The TGA, FTIR, biomass compositions, and O/C ratios suggested that thermochemical reactions played a significant role in the torrefaction at which thermal degradation coupled with possible in situ chemical reactions took place, to some extent. The optimal conditions of the torrefaction were identified at 320 °C and 30 min for SD, and 325 °C and 30 min for BW. The maximum HHVs at the optimal condition were 22, 23, and 20 MJ/kg while the eco-efficiency values were 29.18, 27.89, and 13.72 kJ/kg CO2_eq*THB for torrefied SD, torrefied BW, and coal, respectively. The findings of this study indicate that torrefied rubberwood residues enhanced HHV, eco-efficiency, and less contribution to CO2 emissions compared to fossil fuels.
Aerodynamic Performance and Numerical Validation Study of a Scaled-Down and Full-Scale Wind Turbine Models
Authors: Mehmood Zahid , Wang Zhenyu , Zhang Xin , Shen Guiying
Published: October 2024

Understanding the aerodynamic performance of scaled-down models is vital for providing crucial insights into wind energy optimization. In this study, the aerodynamic performance of a scaled-down model (12%) was investigated. This validates the findings of the unsteady aerodynamic experiment (UAE) test sequence H. UAE tests provide information on the configuration and conditions of wind tunnel testing to measure the pressure coefficient distribution on the blade surface and the aerodynamic performance of the wind turbine. The computational simulations used shear stress transport and kinetic energy (SST K-Omega) and transitional shear stress transport (SST) turbulence models, with wind speeds ranging from 5 m/s to 25 m/s for the National Renewable Energy Laboratory (NREL) Phase VI and 4 m/s to 14 m/s for the 12% scaled-down model. The aerodynamic performance of both cases was assessed at representative wind speeds of 7 m/s for low, 10 m/s for medium, and 20 m/s for high flow speeds for NREL Phase VI and 7 m/s for low, 9 m/s medium, and 12 m/s for the scaled-down model. The results of the SST K-Omega and transitional SST models were aligned with experimental test measurement data at low wind speeds. However, the SST K-Omega torque values exhibited a slight deviation. The transitional SST and SST K-Omega models yielded aerodynamic properties that were comparable to those of the 12% scaled-down model. The torque values obtained from the simulation for the full-scale NREL Phase VI and the scaled-down model were 1686.5 Nm and 0.8349 Nm, respectively. Both turbulence models reliably predicted torque and pressure coefficient values that were consistent with the experimental data, considering specific flow regimes. The pressure coefficient was maximum at the leading edge of the wind turbine blade on the windward side and minimum on the leeward side. For the 12% scaled-down model, the flow simulation results bordering the low-pressure region of the blade varied slightly.
Enhanced Energy Harvesting from Thermoelectric Modules: Strategic Manipulation of Element Quantity and Geometry for Optimized Power Output
Authors: Wu Chun-I , Du Kung-Wen , Tu Yu-Hsuan
Published: October 2024

Rising environmental concerns and increasing electricity generation costs have sparked significant interest in waste heat recovery systems, particularly thermoelectric modules. Given the challenge of breakthroughs in thermoelectric materials, improving module structure has become a key strategy for enhancing efficiency. This study examines the commercially available TGM1-127-1.0-0.8 thermoelectric module through comparative simulation of flat plate and annular configurations. By maintaining consistent conditions across designs—including total volume of thermoelectric material, element geometry, heat source contact area, temperature differential, and connecting copper plate volume—we investigated the relationship between thermoelectric element quantity and module performance. Results demonstrate that the number of thermoelectric elements not only determines the open-circuit voltage but also significantly influences output power. Notably, the output power trend remains consistent across temperature differentials, independent of load resistance variations, suggesting a fundamental relationship between element quantity and module efficiency.
Valorization of Spent Mushroom Compost Through a Cascading Use Aproach
Authors: Londoño Carolina Restrepo , Gil Alexander Giraldo , Moreno Andrés , Alvarado Pedro Nel
Published: October 2024

Spent mushroom compost (SMC) is a waste byproduct generated by the mushroom industry, with the current disposal methods involving landfills or incineration, causing environmental problems. This study introduces a cascading valorization based on circular economy. A water-washing pretreatment is suggested to reduce the ash content and improve the calorific value. Furthermore, an oxidative torrefaction is proposed to enhance the physicochemical properties and evaluate the residence time, temperature, and initial weight effects. The investigation revealed that the calorific value increased by 49.46% in the best water washing scenario and the SMC contains laccase. During SMC torrefaction, mass and energy yields exceeded 80%, and the calorific value was improved. Finally, torrefaction in situ CO2 capture was achieved by forming CaCO3, with a mass fraction increase of up to 7.4%. The study describes the cascading innovation use of this residue on a TRL4 higher than previously reported studies, thereby contributing to gaining an understanding of sustainable industrial mushroom production.
Evolution of the Caprock Sealing Capacity Induced by CO2 Intrusion: A Simulation of the Dezhou Dongying Formation
Authors: Yang Shuo , Tian Hailong
Published: October 2024

CO2–water–rock interactions have an important impact on the stability and integrity of the caprock in CO2 geological storage projects. The injected CO2 in the reservoir enters the caprock via different mechanisms, leading to either the dissolution or precipitation of minerals. The mineral alterations change the porosity, permeability, and mechanical properties of the caprock, affecting its sealing capability. To evaluate the sealing effectiveness of overlying caprock and identify the influencing factors, numerical simulations and experiments were carried out on the mudstone Dongying Formation in Dezhou, China. Based on high-temperature and high-pressure autoclave experiments, batch reaction simulations were performed to obtain some key kinetic parameters for mineral dissolution/precipitation. Then, they were applied to the following simulation. The simulation results indicate that gaseous CO2 has migrated 7 m in the caprock, while dissolved CO2 migrated to the top of the caprock. Calcite is the dominant mineral within 1 m of the bottom of the caprock. The dissolution of calcite increases the porosity from 0.0625 to 0.4, but the overall porosity of the caprock decreases, with a minimum of 0.054, mainly due to the precipitation of montmorillonite and K-feldspar. A sensitivity analysis of the factors affecting the sealing performance of the caprock considered the changes in sealing performance under different reservoir sealing conditions. Sensitivity analysis of the factors affecting the sealing performance of the caprock indicates that the difference in pressure between reservoir and caprock affects the range of CO2 transport and the degree of mineral reaction, and the sealing of the caprock increases with the difference in pressure. Increasing the initial reservoir gas saturation can weaken the caprock’s self-sealing behavior but shorten the migration distance of CO2 within the caprock. When the content is lower than 2%, the presence of chlorite improves the sealing performance of the caprock and does not increase with further chlorite content. This study elucidates the factors that affect the sealing ability of the caprock, providing a theoretical basis for the selection and safety evaluation of CO2 geological storage sites.
Applying the International Maritime Organisation Life Cycle Assessment Guidelines to Pyrolysis Oil-Derived Blends: A Sustainable Option for Marine Fuels
Authors: Prussi Matteo
Published: October 2024

Reducing maritime greenhouse gas (GHG) emissions is challenging. As efforts to address climate change are gaining momentum, reducing the environmental impact becomes crucial for maritime short-to-medium-term sustainability. The International Maritime Organisation (IMO) has adopted Life Cycle Assessment (LCA) guidelines for estimating GHG emissions associated with alternative fuels. This paper proposes an examination of the latest IMO-adopted LCA guidelines, comparing them with existing methodologies used for the transport sector. By scrutinising these guidelines, the paper aims to provide a better understanding of the evolving landscape for GHG emission estimation within the maritime sector. The paper presents a case study that applies the newly established LCA guidelines to a promising alternative fuel pathway, i.e., waste-wood-derived pyrolysis oil. Pyrolysis oil offers an attractive option, leveraging waste materials to generate a sustainable energy source. The environmental impact of pyrolysis oils is quantified according to the IMO LCA guidelines, offering insights into its viability as a cleaner alternative as marine fuel. The results show the large potential for GHG savings offered by this pathway: upgraded pyrolysis oil can deliver significant GHG savings, and this contribution is linearly dependent of its energy share when blended with standard Heavy Fuel Oil.
Runoff Change Characteristics and Response to Climate Variability and Human Activities Under a Typical Basin of Natural Tropical Rainforest Converted to Monoculture Rubber Plantations
Authors: Xue Shiyu , Zhu Lirong , He Yanhu , Li Dan , Ye Changqing
Published: October 2024

Climate variability and human activities are major influences on the hydrological cycle. However, the driving characteristics of hydrological cycle changes and the potential impact on runoff in areas where natural forests have been converted to rubber plantations on a long-term scale remain unclear. Based on this, the Mann–Kendall (MK) and Pettitt breakpoint tests and the Double Mass Curve method were employed to identify the variation characteristics and breakpoints of precipitation (P), potential evapotranspiration (ET0), and runoff depth (R) in the Wanquan River Basin (WQRB) during the 1970–2016 period. The changes in runoff attributed to P, ET0, and the catchment characteristics parameter (n) were quantified using the elastic coefficient method based on the Budyko hypothesis. The results revealed that the P and R in the WQRB exhibited statistically insignificant decreasing trends, while ET0 displayed a significant increasing trend (p < 0.05). The breakpoint of runoff changes in the Jiabao and the Jiaji stations occurred in 1991 and 1983, respectively. The runoff changes show a negative correlation with both the n and ET0, while exhibiting a positive correlation with P. Moreover, it is observed that P and ET0 display higher sensitivity towards runoff changes compared to n. The decomposition analysis reveals that in the Dingan River Basin (DARB), human activities account for 53.54% of the runoff changes, while climate variability contributes to 46.46%. In the Main Wanquan River Basin (MWQRB), human activities contribute to 46.11%, whereas climate variability accounts for 53.89%. The research findings suggest that runoff is directly reduced by climate variability (due to decreased P and increased ET0), while human activities indirectly contribute to changes in runoff through n, exacerbating its effects. Rubber forest stands as the prevailing artificial vegetation community within the WQRB. The transformation of natural forests into rubber plantations constitutes the primary catalyst for the alteration of n in the WQRB. The research findings provide important reference for quantifying the driving force of hydrological changes caused by deforestation, which is of great significance for sustainable management of forests and water resources.
Stem Longitudinal Gradient for Basic Density, Carbon, Nitrogen, and CN Ratio in Khaya spp.: Improved Correlation Using Diameter Instead of Commercial Height
Authors: Momolli Dione Richer , Caldeira Marcos Vinicius Winckler , Gomes Gabriel Soares Lopes , Gomes Robert , Duarte Victor Braga Rodrigues , Godinho Tiago de Oliveira , da Silva João Gabriel Missia , dos Santos Vaniele Bento , Vidaurre Graziela Baptista , Faria Júlio Cézar Tannure , Schumacher Mauro Valdir , Pereira Marcos Gervasio
Published: October 2024

The basic wood density influences the carbon stock, playing a crucial role in climate-changing global mitigation through carbon sequestration. Understanding wood carbon release depends on the Nitrogen assessment and CN ratio. Therefore, our research aimed to: (i) Compare basic density, organic carbon, nitrogen, and C/N ratio among the Khaya grandifoliola, K. ivorensis, and K. senegalensis; (2) Analyze the gradient along positions and diameter of the commercial stem; (3) Recommend the most representative sampling position for each species based on the diameter. The experimental area is located in Southeastern Brazil. Twelve average-diameter trees per species were cut down, and wood disc samples were collected at 0, 25, 50, 75, and 100% commercial height. Our results show statistical differences in wood basic density among the species, and K. senegalensis has the highest basic density, 592 kg m3. There was no statistical difference in organic carbon between species and along the stem. Stem diameter instead of commercial height improved the variable studied, confirming the research hypothesis. Sampling at 17% of the commercial height, ranging to 18–22 cm stem diameters, is recommended for greater representativeness.