bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical simulation on water exchange affected by tidal and runoff in Xiaohai Lagoon, Hainan province
Authors: Meng Hui , Zhang Xueqing
Published: September 2024

Xiaohai Lagoon is the largest lagoon in Hainan, connected to the open sea through a narrow channel. In this study, a hydrodynamic numerical model based on the FVCOM model is established to quantitatively investigate the water exchange characteristics between Xiaohai Lagoon and the open sea under tidal and runoff conditions, utilizing concepts such as residual flow, tidal prism, and half-life time. Under the influence of runoff effect, the water exchange capacity in the lagoon has significant spatial variations, and the closer the distance to the estuary and inlet compared to the tidal drive, the faster the water exchange. The strongest areas of water exchange capacity in the Xiaohai lagoon are located in the mouth, tidal channel and estuary areas, and the weakest area is the southeastern part of the lagoon. The simulation results showed that the runoff input has a certain promotion effect on the water exchange in the lagoon, especially in the scouring effect of freshwater in the estuary area, the easier the water exchange between the sea areas.
Growth and phosphate uptake of microalgae under different phosphate conditions
Authors: Wei Cao
Published: September 2024

Microalgae could utilize the nutrients in the environment and therefore are widely used in wastewater treatment. The variety and complexity of phosphates in the water column and different types of wastewater can affect the growth of microalgae, which further affects the treatment efficiency of phosphorus- containing wastewater. In this study, phosphate uptake and microalgal growth were investigated under different phosphate conditions. The results showed that the increase of phosphate concentration could promote the growth of microalgae. Phosphate species affected the phosphate uptake and transformation process. Orthophosphate and polyphosphate were first adsorbed on the surface of microalgae and then transported inside the cell. Polyphosphates produce desorption in the early stages of uptake. The adsorbed polyphosphates were released back into the culture medium and were taken up and utilized again in the later stages of incubation. Polyphosphates were taken up and utilized by microalgae for a longer period of time than orthophosphates. It was also found that orthophosphate was more readily utilized by microalgae compared to polyphosphate. An increase in phosphate concentration promotes the growth of microalgae.
Alternating Direct Current Field Assistant Promoting Chemical Stabilization of Combined Heavy Metals Contaminated Soil
Authors: Mi Ruidong , Jin Jiyuan , Zhang Cunkuan , Long Linzi , Ding Wenchuan , Huang Renli , Ding Sicheng
Published: September 2024

To enhance the remediation efficiency and reduce the chemicals consumption, the combined heavy metals Lead (Pb), Copper (Cu) and Cadmium (Cd) contaminated soil were stabilized by chemical passivators with alternating direct current field (ADC) assistant. The results showed that ADC treatment activated initial heavy metal compounds in the soil. The leaching concentrations of Pb, Cu and Cd in soil under ADC condition increased by 19.61%, 38.77% and 49.10% in comparison with no electric field, respectively. The exchangeable fractions of Pb, Cu and Cd increased while the reducible, oxidizable and residual fractions decreased substantially. Thus, the chemical passivators addition companied with ADC treatment in the beginning increased stabilization efficiency of heavy metals in the soil and reduced over 30% amount of chemical agent consumption, comparing with only chemical passivator stabilization. The mechanism can be speculated that ADC assistant facilitated more heavy metal ions in the soil reacting with phosphorus- containing passivator to formed more complex and stable metal phosphates. It was confirmed by XRD measurement that silicon element in the crystal structure of metallic compound was replaced by phosphorus element.
Assessing the Impact of Organic-Inorganic Nitrogen Application on Maize Yield and Nitrogen Leaching Using the DNDC Model
Authors: Liu Hu , Zhou Hui , Li Hongfang
Published: September 2024

In order to optimize maize yield and minimize nitrogen leaching, field experiments and DNDC model simulations assessed various organic-inorganic nitrogen application treatments. Trials were conducted in the Hetao irrigation area of Inner Mongolia, comparing six treatments: no nitrogen (CK), solely inorganic nitrogen (U1), and combinations where 25%, 50%, 75%, and 100% of inorganic nitrogen was replaced with organic nitrogen (U3O1, U1O1, U1O3, O1). The DNDC model was calibrated using the U1 treatment data from 2018-2020 and validated with other treatments. Results indicated the model accurately simulated maize yield (NRMSE < 5°%) and nitrate nitrogen leaching (NRMSE < 15%). Simulation outcomes demonstrated that increasing inorganic nitrogen application reduced crop yield and significantly increased nitrate leaching. Conversely, higher proportions of organic nitrogen, along with adjusted irrigation and frequency of inorganic nitrogen fertilization, increased maize yield while reducing nitrate leaching. At a fixed nitrogen application rate of 240 kg hm−2, maize yield initially rose and then declined with increasing organic nitrogen ratios, while nitrate nitrogen leaching decreased consistently. Optimal results were achieved with a 3:2 ratio of organic to inorganic nitrogen, yielding 12578 kg hm−2 with nitrate nitrogen leaching at 15.7 kg NO-3-N hm−2, indicating this ratio as the preferred method for combined nitrogen application in the region.
Analysis and Discussion on the Current State and Demand of Energy Supply for Highway Transportation Facilities
Authors: Wang Jian , Liu Zhiqiang , Qiang Rongrong , Xia Lishuang
Published: September 2024

Energy supply is a crucial factor in realizing the future transformation of highway transportation. Determining a comprehensive and sustainable energy supply network that aligns with the demands of future highway transportation facilities - ensuring they are "safe, reliable, environmentally friendly, efficient, and sustainable" - poses a key challenge for current highway developers and operational managers. This study examines the types and energy consumption of significant energy-consuming facilities along expressways. It delves into the current state of power supply and distribution technologies for highway transportation facilities, including low-voltage, medium-voltage, and complementary wind and solar power systems. Additionally, the research analyzes existing issues within power supply and distribution systems for highway transportation facilities. The study investigates the load characteristics and spatial distribution of electricity-consuming facilities along expressways, concluding with an analysis of the future trends in energy demand for highway transportation facilities. This comprehensive exploration encompasses aspects such as the scale of energy demand, the diversification of energy supply, and the need for a secure, efficient, and intelligent energy supply. The findings aim to provide valuable insights for developing innovative, diverse energy supply, and control technologies for safe, efficient, and interconnected highway transportation facilities.
Real-Time Monitoring Technology for Carbon Emissions in Mountain Expressway Tunnel Construction
Authors: Yang Jiaqi , Li Jingdong , Liu Zhiqiang , Qiang Rongrong , Liu Yongmin , Li Zhijun , Liang Hua
Published: September 2024

The complexity of tunnel construction places it in a position of great importance in the overall construction of highways, and the carbon emissions generated during its construction also account for a large portion. The report of the 20th National Congress of the Communist Party of China pointed out the need to "actively and steadily promote carbon peaking and carbon neutrality." As one of the main contributors of carbon emissions, the transportation industry needs to actively increase its efforts to reduce emissions, innovate ways to reduce emissions, and not overlook any sources of carbon emissions. This article relies on the Linshuang Expressway project, which combines theoretical calculation logic with information and Internet of Things technology to complete the construction of a real-time monitoring system for carbon emissions during tunnel construction in mountainous areas. Through this system, construction carbon emissions can be visualized and monitored in real-time, providing reliable data support for emission reduction in tunnel construction, and providing technical references for promoting low-carbon, clean, and green highway tunnel construction, in order to further support the development of a strong transportation country.
Development of nuclear industry: The roles of international civil liability legal regime for nuclear damage
Authors: Liu Jiu , Shen Le , Liu Yi , Gao Yuetong , Wu Jingyi
Published: September 2024

As International Atomic Energy Agency has stated in its Handbook on Nuclear Law, "Even in situations for which the highest standard of safety has been achieved, the occurrence of nuclear accidents cannot be completely excluded." Therefore, the international legal framework for nuclear damage compensation liability has been evolving since the establishment of Nuclear Energy Agency of Organization for Economic Co-operation and Development (OECD NEA) and International Atomic Energy Agency (IAEA). Over the years, various international treaties have been enacted to address the compensation of nuclear damage and to establish liability regimes for nuclear incidents. To date, these treaties have established a series of legal principles of nuclear damage liability, such as the sole liability principle, the strict liability principle, the financial guarantee principle etc., which have been developing since establishment. This paper offers an overview of the historical development of the principles of these international treaties for nuclear damage liability and thus draws upon both primary and secondary sources, including treaties, official documents, academic literature, and reports by international organizations. The paper reveals that with the awareness of protecting public's rights having been significantly strengthened, the range of compensation has been broader, the matters of immunity from liability for operators of nuclear power plants have been reduced, the limitation of the compensation amount has been higher etc. In conclusion, the international legal regime for nuclear damage liability has been showing a shift from protecting the development of the nuclear industry to a joint protection of both public health and rights and the nuclear industry.
Study on displacement and imbibition law of tight sandstone reservoir
Authors: Rongkai Yuan , Pingb Jiang , Guicai Zhang , Zhinan Liu
Published: September 2024

Due to the rapid increase of the world's energy demand, people gradually put the focus of oil and gas development on unconventional. Tight reservoir as an important part of unconventional, how to improve the recovery rate of tight reservoir has become the focus of the times. In this paper, the relationship between oil saturation and recovery rate of tight reservoir is explained by displacement and imbibition experiments on cores with different oil saturation, and the mechanism is explained by nuclear magnetic resonance, which provides direction for improving the recovery rate of tight reservoir.
Research on the spatiotemporal evolution and driving mechanism of coupling coordination between energy structure transformation and common prosperity
Authors: Sun Yikai , Ye Chengjin , Huang Jingjing
Published: September 2024

Promoting the transformation of energy structure is the important method to realize common prosperity in China. This paper estimates China's energy structure transition, explores the spatial evolution characteristics of the coupling and co-ordinated development of energy structure transformation and common prosperity, and analyzes its driving mechanism. The results show that the comprehensive evaluation index and coupling coordination degree of energy structure transformation and common prosperity show a steady improvement trend. The coupling coordination type is between low-degree and high-degree coordination. The coupling coordination degree presents a spatial allocation pattern of high in the east and low in the west, high in the center and low in the south. The transformation of energy structure and the drive of common prosperity are greatly affected by macroeconomics and policies. This study provides an empirical reference for promoting the transformation of energy structure and the realization of common prosperity.
New Energy Vehicle Development and Electricity Demand Forecasting Based on Random Forest Model
Authors: Zhou Lin , Wang Kun , Zhang Weiwei
Published: September 2024

With the implementation of the green economy and the decarbonization strategy, the new energy automobile industry has developed rapidly in China, which poses new challenges to the balance and stability of the power system. This paper predicts the development trend of China's new energy vehicle industry through the random forest model, and analyses the impact of the development of new energy vehicles on power demand. The results show that the number of new energy vehicles in China is expected to increase significantly, accounting for a quarter of the total number of vehicles, and the number of charging piles will increase significantly to meet the demand. With the development of the new energy automobile industry, the demand for electricity and power load in the whole society are expected to maintain rapid growth, which poses new challenges to the power supply stability of the power grid. This study provides an important reference for government regulation, power grid adaptation and new energy vehicle enterprise development planning.
Strength analysis of feeding device of coal-bed methane truck-mounted drilling rig
Authors: Qi Liu
Published: September 2024

Feeding device is the main working part of coal-bed methane truck-mounted drilling rig. In this paper, through analyzing the structural strength characteristics of the feeding device of the CBM truck- mounted drilling rig, the secondary feeding device and the pulley frame, which are the main bearing components, are selected for strength analysis. The three-dimensional model of the feeding device drawn by solidedge was imported into ABAQUS and the finite element model was established to analyze the main load- bearing parts under the limit condition of strong pulling. The analysis shows that under this working condition, the strength of the feeding device fully meets the design requirements. Finally, through the physical prototype performance test, the strength analysis results of the feeding device of the CBM drilling rig are verified.
A study of automobile market structure prediction based on multivariate logit model with embedded Newton's method
Authors: Yufan Jiao , Bingyu Zhang , Panchun Liang
Published: September 2024

In order to deeply understand the factors that consumers focus on when choosing models with different technological routes, and to predict the structure of the future automobile market accordingly, a multivariate logit model incorporating Newton's method of optimization is used, which is able to accurately measure the weights of the various factors that influence the process of choosing models by consumers, in order to reflect the degree of heterogeneity of consumers' preferences for these factors, and to predict the future market share of the different technological routes on the basis of this model. Based on this, it predicts the share of different technological routes in the future market. The results of this study show that when choosing a vehicle of different technological routes, convenience of replenishment is the most important factor, with a preference weight of 0.39. In contrast, the imitation coefficient has the lowest preference weight of 0.11, which suggests that consumers are more likely to take into account their personal experience rather than the choices made by others in their vehicle purchasing decisions. In addition, in the prediction of future technological routes in the automobile market, it is also found that by 2025, consumers' tendency to choose new energy vehicles will be more than 50%, and by 2030, the proportion will be more than 70%. Meanwhile, the market share of sales of traditional fuel vehicles is expected to fall to 17% by 2035.
Study on the multi-level evaluation method of small hydropower sustainable development
Authors: Qiao Haijuan , Lei Lei , Zhang Conglin , Wang Weiwei
Published: September 2024

Currently, there is a lack of a comprehensive evaluation method for assessing the sustainability of small hydropower at different levels. This deficiency hinders the rational planning of small hydropower development and utilization, as well as the delicate balance between safeguarding and harnessing small hydropower resources. To address this gap, this study primarily focuses on establishing a comprehensive evaluation system for the sustainability of small hydropower at the international, national, and individual power station levels. On the international stage, an evaluation index system is formulated, and a national quantitative assessment model for small hydropower sustainability is developed using the Analytic Hierarchy Process (AHP) combined with fuzzy evaluation techniques. The research is exemplified by investigating countries within the Belt and Road Initiative. At the national level, models for assessing the overall development status and spatial distribution patterns of small hydropower are created. The study thoroughly examines the temporal and spatial evolution patterns and trends in the sustainable development of small hydropower in various provinces and states, with China serving as a case study. At the individual power station level, a green evaluation model is established to comprehensively assess small hydropower stations. This model considers ecological, social, managerial, and economic dimensions to evaluate the environmental sustainability of each small hydropower station.
Optimization of Wellbore Annulus Cleaning Tool Based on CFD-DEM and Box-Behnken Design
Authors: Hu Wei , Zhang Jinya , Guan Ning , Zhang Yanping , Xu Binggui , Zhu Hongwu
Published: September 2024

During the oil and gas drilling process, inefficient cuttings transport may elevate cuttings concentration, leading to higher Equivalent Circulating Density (ECD) and easily triggering a series of wellbore stability issues. In this paper, a new type of annulus cleaning tool is developed, incorporating the H- B non-Newtonian fluid model and a coupled CFD-DEM to construct a numerical model for analyzing the cuttings transport behavior within the multi-layer wellbore annulus using the cleaning tool. The model, validated against experiments, reveals factors affecting Cuttings Transport Ratio (CTR). Through Box- Behnken Design (BBD), Response Surface Methodology (RSM), and Analysis of Variance (ANOVA), a correlation function for CTR is derived to optimize the cleaning tool parameters. Findings show an initial increase then decrease in CTR with nozzle quantity, diameter, and angle. Decreasing hydraulic diameter enhances CTR, whereas nozzle diameter variation has minimal impact at smaller diameters. After optimization, CTR reaches 95.76% with 4 nozzles of 10mm diameter, 32° angle, and 57mm hydraulic diameter. These results guide cleaning tool optimization design , improving cuttings transport efficiency, and ensuring safe oil and gas production.
Layout optimization of heliostat field based on genetic algorithm
Authors: LIu Yuan , Tang Yi , Cong Weijie
Published: September 2024

In order to improve the annual average optical efficiency of a tower solar power plant, a simulated heliostat field layout optimization model is constructed using ray tracing method to calculate the shadow shading efficiency. is constructed using ray tracing method to calculate the shadow shading efficiency. Genetic algorithms are used to encode the variables such as solar pitch angle, solar azimuth angle, and coordinates of heliostat mirrors in chromosomal individuals in binary regions, and to find the near-optimal solutions in iterative populations through the use of ray tracing method. Simulation results show that the model can significantly optimize the layout of the tower solar power system. Simulation results show that the model can significantly optimize the layout of the tower solar power plant and improve the annual average optical efficiency. neighboring heliostats is at 0.398 times the sum of the length and width, the optical efficiency of the Khi Solar One power plant reaches 61.83%, which is an improvement of 15.74% compared to that of the Khi Solar One power plant. improvement of 15.74% compared to this engineering example.
Analysis of Carbon Footprint Assessment and Accounting System of Photovoltaic Industry under Dual-Carbon Background
Authors: Zhang Congguang , Li Zhengguo , Yan Lifei , Liu Hui , Luo Xinlei
Published: September 2024

With the intensification of global climate change and the growing demand for the Sustainable Development Goals (SDGs), dual-carbon policies are on the rise globally, bringing new challenges and opportunities to the energy industry. Focusing on the photovoltaic (PV) industry, this study carries out a carbon footprint analysis in the context of dual-carbon to gain a comprehensive understanding of the current status of PV modules in terms of carbon emissions and emission reduction measures. This paper firstly summarizes the development of the PV industry, and deeply analyzes the relevant theories and methods of carbon footprint assessment and accounting system. Then, it systematically evaluates the carbon emissions of crystalline silicon PV modules throughout their life cycle, and based on this, it puts forward suggestions on strategies to reduce the carbon footprint. Finally, the opportunities and challenges that the PV industry may encounter in the process of moving towards a low-carbon future are discussed to provide a reference for decision-making and practice in this field.
Prospects and Management Strategies for High Noise, Soft Geological and Strong Earthquake Environments
Authors: Gao Jie , Ma Yuchao , Li Yigang , Fang Zhenggang , Li Xiang , Yang Zhen
Published: September 2024

With global warming, environmental degradation is becoming increasingly severe, and the impact on power transmission and transformation equipment is increasing. The changing environment will also have cross impacts, and people are paying more attention to environmental protection. Therefore, under complex environmental conditions, research on new technologies continues, and the emergence of new technologies can improve efficiency and reduce costs. This article focuses on three typical environments: noise environment, soft geological environment, and seismic environment, with a focus on analysing their latest technological situation and management strategies. At the same time, it proposes future development directions, guides the emergence of new business models and service methods, and promotes industry innovation and change.
Research on the sustainable development of scenic-dependent rural spaces: A Case Study of Heping Village
Authors: Wang Xinman , Zhu Rong
Published: September 2024

Scenic-dependent rural areas, as a distinct category of rural spaces, are a significant element that cannot be overlooked in China's current efforts towards sustainable rural development. This study focuses on the spatial issues encountered during the development of scenic-dependent rural areas, taking Heping Village as a case study. It emphasizes the needs of the users and employs Space Syntax to analyze spatial patterns at three levels: points, lines, and areas. By adjusting the spatial sustainable layout, accessibility, and complexity, a model for sustainable rural spatial development is proposed, characterized by "one village, two cores, three axes, four zones, and multiple points." The aim of this model is to reconstruct the inadequacies of spatial arrangement within the village and promote the sustainable development of scenic-dependent rural areas through a symbiotic approach.
The Energy Transition - The challenges of defossilisation
Authors: Bonhomme Gérard
Published: September 2024

This special report on energy marks the culmination of a long-term project by the SFP’s Energy & Environment Committee. The initial impetus for the project was provided by Michel Spiro. In the editorial entitled “Physicists facing the challenge of global warming” in issue No. 55 of Reflets de la physique (October-November 2017), he already indicated the main themes in which physicists should get involved to face this global challenge of the energy transition. This transition must lead to a move away from fossil fuels, which currently account for more than 80% of primary energy resources supply worldwide and provide around 60% of our final energy consumption in France and Europe.

The scale of the challenge is immediately clear!
New challenges for French energy policy
Authors: Percebois Jacques , Pommeret Stanislas
Published: September 2024

France now faces three new challenges in implementing its energy policy.

It needs to move away from carbon-based fossil fuels in order to meet the target of carbon neutrality by 2050, and this will involve raising the price of carbon. Secondly, it needs to invest massively in electricity generation to meet the growing demand for electricity as a result of the electrification of energy uses, and this requires investment in dispatchable, low-carbon nuclear power. Finally, France must rise to the challenge of large-scale storage and retrieval of renewable energies, and look at the extent to which electric mobility can contribute to this.

We also need to rethink the way the electricity markets operate if we are to ensure that these challenges are financed.
Scenarios for an energy transition
Authors: Bobin Jean-Louis
Published: September 2024

Developed on behalf of decision-makers or whistleblowers, scenarios describe stories that could happen. They involve assumptions about the socio-economic future of humanity and must take account of constraints, the main one being the threat of man-made climate change.
Energy uses of biomass
Authors: Boissonnet Guillaume
Published: September 2024

The climate and geopolitical context are forcing our societies to look at how best to use new energy resources without contributing to the greenhouse effect. However, “greenhouse neutral” does not mean carbon-free. Assessing carbon neutrality must therefore be carried out across the entire processing chain, and the laws of thermodynamics apply at every stage.

In today’s energy mix, fossil carbon dominates. And even in a future system, carbon will remain essential for materials, chemicals and energy, just as it is for food. We shall see that it is not so much a question of “decarbonising” the system as of “defossilising” it. Since carbon is a critical resource, we need to encourage the best uses of it and maximise its conversion efficiency.
Wind energy, from the perspective of physics
Authors: Peinke Joachim , Fuchs André
Published: September 2024

Electrical energy is one of the most valuable forms of energy, as it can be optimally transported and converted into other forms of energy with low losses.

Most future scenarios predict that electrical energy consumption will continue to grow significantly, and that the share of renewable energies, due to their abundance, will also increase.

This contribution focuses on wind power, discussing how it works and its contribution to the overall energy supply.
Offshore wind power: from fixed to floating
Authors: Gilloteaux Jean-Christophe , Aubrun Sandrine
Published: September 2024

Wind power is expected to make the biggest contribution to renewable energy deployment targets for 2030 and beyond. Installed wind power capacity in the European Union is around 236 GW (end 2021); with 207 GW of onshore wind and 28 GW of offshore wind, it covers 15% of electricity demand (8% in France). The most promising scenarios aim to achieve a total capacity of 60 to 80 GW of installed offshore wind power by 2030, including 6 to 12 GW of floating offshore wind power.

This article provides some background on offshore wind energy. The advantages of floating wind power, the associated obstacles and innovative hybrid experimentation systems are briefly outlined.
Nuclear fusion by magnetic confinement: advances, challenges and prospects
Authors: Bonhomme Gérard
Published: September 2024

Mastering fusion energy would offer a low-carbon energy resource of major interest. With ITER, the experimental reactor under construction at Cadarache, research will enter a decisive phase.

This article describes the principles of nuclear fusion by magnetic confinement, the steps taken up to the ITER project, and its objectives. The future of fusion depends on other research currently underway, in particular the choice of the optimum magnetic configuration. The implementation of breakthrough technologies, particularly in the field of materials, could also prove decisive for the future of fusion.
Does intermittent electricity jeopardise grid stability?
Authors: Sapy Georges
Published: September 2024

Intermittent sources of electricity (solar photovoltaic and wind power) supply electricity grids in very different ways to dispatchable sources (hydro, nuclear or fossil fuel power plants).

This article sets out these specific features and gives some indications of the solutions that will need to be implemented to guarantee grid balance in the event of strong growth in intermittent sources.
The weight of mineral resources in energy systems
Authors: Bonhomme Gérard , Treiner Jacques , Vidal Olivier
Published: September 2024

Humanity is using mineral resources at an unprecedented rate, and demand will continue to grow over the coming decades, fuelled by the energy and digital transitions and the economic development of highly populated countries. But the nature and quantities of mineral resources needed are highly dependent on the types of use envisaged, which vary according to the organisation and level of development of societies.

The demand for raw materials must therefore be estimated using a dynamic and regionalised approach, taking into account the different development scenarios, particularly as regards the deployment of renewable or decarbonised energy resources.

This article summarises the main analyses of previously published articles by Olivier Vidal et al. [1-4].
Sanitary energy costs
Authors: Masse Roland
Published: September 2024

Energy production and consumption are essential to the development of industrial societies. It has been shown that there is a strong correlation between the increase in life expectancy and the amount of energy per capita, but that this effect reaches a plateau at a value of less than a quarter of that of current Western societies.

In addition to energy consumption, the interaction between energy and health is dominated by the effects of environmental pollution.
Analysis of painful situations during unsedated esophagogastroduodenoscopy
Authors: Kanzaki Hiromitsu , Kuraoka Sakiko , Satomi Takuya , Okanoue Shotaro , Hamada Kenta , Kono Yoshiyasu , Iwamuro Masaya , Kawano Seiji , Kawahara Yoshiro , Okada Hiroyuki , Otsuka Motoyuki
Published: September 2024

Background and study aims Although esophagogastroduodenoscopy (EGD) is a widely used technique, the procedure is often associated with discomfort. This study aimed to analyze painful situations, their frequency, and factors associated with patient discomfort during EGD.

Patients and methods This prospective observational study included patients scheduled to undergo EGD. Seven endoscopists recruited patients scheduled for EGD screening or surveillance. Each endoscopist enrolled 20 patients, performing 10 EGD procedures using ultraslim endoscopes and 10 with standard-sized endoscopes. Data regarding painful situations and frequency were collected using specialized buttons pressed by the patients during EGD. A survey about overall discomfort was conducted after the procedure.

Results We analyzed data from 140 patients. Esophageal insertion and duodenal observation were associated with the highest incidence of pressing the pain button, accounting for 59.3% and 40.7% of the cases, respectively. The factor associated with pressing the pain button during esophageal insertion was endoscopist experience (< 10 years). In contrast, younger age and female sex were the factors associated with pressing the pain button during duodenal observation. In the post-procedure survey, 63.6% of patients reported discomfort. Factors associated with patient discomfort included pressing the pain button during esophageal insertion (odds ratio [OR]: 2.84, P = 0.01) and previous painful EGD experience (OR: 2.41, P = 0.03).

Concusions This study provides objective data on painful situations, their frequency, and related factors during EGD. Further research and interventions focusing on pain reduction during endoscopic procedures are warranted. The results of this study will help endoscopists manage painful situations and potentially improve skills.
Conservative Management of Necrotizing Enterocolitis in Newborns: Incidence and Management of Intestinal Strictures
Authors: Mena Rach , Guillén Gabriela , Lopez-Fernandez Sergio , Martos Rodríguez Marta , Ruiz César W. , Montaner-Ramon Alicia , López Manuel , Molino José A.
Published: September 2024

Background Necrotizing enterocolitis (NEC) is one of the main causes of acute abdomen in neonates. Surgical treatment entails important morbidity and mortality and conservative management, when possible, offers better outcomes. Post-NEC intestinal strictures are one of the main complications.

Methods Retrospective analysis from June 2011 to November 2022 of post-NEC strictures (PNS) after conservative management of neonates diagnosed with NEC (modified Bell stage IIA or higher) at a tertiary neonatal surgery center.

Results Out of 219 NEC, 126 received initial conservative management (57.5%), 24 (19%) of which eventually underwent surgery for PNS. Average gestational age and weight at birth of our cohort were 31.3 ± 4.9 weeks and 1,694 ± 1,009 g.

PNS diagnosis was made 38.4 ± 16.5 days after the NEC episode. 6/24 (25%) were asymptomatic and diagnosed by screening enema, 11 (46%) presented signs of intestinal obstruction before the enema could be performed and 7 (29%) after a normal previous protocol study.

Median age at PNS surgery was 56 ± 17.9 days. A total of 2/3 strictures were found in cecum, ascendent, and transverse colon. Primary resection and anastomosis were performed in all cases. Feeds were restarted on postoperative day 4.3 ± 2.9. Two cases presented anastomotic complications (1 dehiscence and 1 stenosis), and no deaths were recorded.

Conclusions PNS is a frequent complication after conservative management. Deffered surgical treatment after the acute NEC episode is resolved allows for safer surgeries (since patients have reached hemodynamical stability and overcome septic shock), shorter resections, and favorable postoperative outcomes.
Endoscopic submucosal dissection of colorectal pedunculated polyps
Authors: Jakobs Johanna Katharina , Zumblick Malte , von Gerlach Susanne , Stathopoulos Petros , Glas Sebastian , Denkert Carsten , Denzer Ulrike Walburga
Published: September 2024

Background and study aims For pedunculated colon polyps, en bloc resection with inclusion of the polyp stalk is necessary to yield an accurate histologic staging. This can be challenging in cases of a large polyp and/or broad stalk using conventional snare resection. We evaluated the feasibility of endoscopic submucosal dissection (ESD) for large pedunculated polyps with broad stalks.

Patients and methods Between February 2019 and November 2021 all patients with large pedunculated polyps defined as polyp diameter ≥ 20 mm and or a broad stalk > 5 mm were enrolled in the study. All polyps were resected in ESD technique with dissection of the polyp stalk at the base after injection.

Results Twenty-five patients (male = 18, age mean: 67 years) were
included. En bloc resection was achieved in 100% of the patients (25/25 polyps). Polyps were
mainly located in the sigmoid (n = 19) and rectum (n = 3). Median polyp size was 30×25×17 mm.
Histologic examination revealed the following results: adenoma low-grade intraepithelial
neoplasia (LG-IEN): nine; high-grade intraepithelial neoplasia (HG-IEN): seven; pTis: three;
adenoarcinoma: five (G1, pT1, L0, V0, Haggitt 3: 2/G2, pT1, L0, V0, Haggitt 3:2/G3, pT1, Bd3,
V1, Haggitt 4: 1); other: 1.

R0 resection rate was 100% and the curative resection rate yielded 96% (24/25) without severe adverse events.

Conclusions ESD achieved high en bloc and R0 resection rates for large pedunculated polyps. In our collective, up to 32% of polyps already had adenocarcinoma, resulting in a high curative resection rate due to complete resection and subsequently accurate risk classification.
Initial experience with transmural use of a new endoscopic ultrasound electric core needle biopsy device: Case series
Authors: Mendoza Ladd Antonio , Alsamman Amer , Meiklejohn Karleen , Viramontes Omar
Published: September 2024

Background and study aims Endoscopic ultrasound-guided biopsy via fine-needle biopsy/fine-needle aspiration (FNB/FNA) is currently the standard method to sample tumors in the mediastinum and abdomen. Although specimens obtained with these needles are acceptable, a histological diagnosis is not always possible. Recently, a new EUS-guided core needle biopsy (EUS-CNB) device became available. Herein, we describe the first experience with its use in a transmural fashion.

Patients and methods This was a case series of patients who underwent EUS-CNB at an academic center. All patients provided written informed consent and were observed in the hospital ≥ 48 hours after the procedure.

Results A total of 8 patients underwent EUSC-CNB: five in the pancreas, two in the retroperitoneum, and one in the mediastinum. The diagnostic accuracy of EUS-CNB was 100% after one actuation. In four patients, same-session FNB and EUS-CNB were obtained from the same lesion with superior tissue sample in the latter. No adverse events were documented.

Conclusions To our knowledge this is the first report on transmural use of EUS-CNB in gastroenterology. Our findings suggest that the device is effective and safe. Larger studies comparing it with FNA/FNB needles will be required to further assess performance and safety.
Anticancer Potential of Quercetin on Oral Squamous Cell Carcinoma: A Scoping Review and Molecular Docking
Authors: Afriza Dhona , Arma Utmi , Faslah Raefany , Suriyah Wastuti Hidayati
Published: September 2024

Oral squamous cell carcinoma (OSCC) is a type of cancer that has a low survival rate and high recurrence and metastasis rates. To date, there is still no effective treatment for OSCC. Various types of cancer, including OSCC, have reported quercetin to act as an anticancer agent, but there is no clear research data on how it may affect OSCC. To determine the anticancer potential of quercetin in OSCC, we conducted a scoping review, and to determine the interaction of quercetin with one of the proteins that plays a role in carcinogenesis, namely, BCL-2, we conducted molecular docking. The scoping review process was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews. The scoping review was searched by collecting articles related to the research topic in Google Scholar, PubMed, ScienceDirect, Cochrane, and EBSCOhost databases. All of the literature records found during the search were imported into the Mendeley software to remove duplication. Nine studies were generated after the titles and abstracts were reviewed according to the inclusion and exclusion criteria. After the full-text screening, no studies were excluded, leaving nine publications determined to be eligible for inclusion in the scoping review. Quercetin showed effects on inhibiting cancer invasion, migration, proliferation, and many protein expressions, as well as increasing cell apoptosis. Molecular docking was done for quercetin and BCl-2 protein. Doxorubicin was utilized as a comparison ligand. The in silico study was utilized using AutoDock Vina, AutoDock Tools 1.5.6, Biovia Discovery Studio 2021, and PyMol. Molecular docking indicated quercetin has a strong binding affinity with BCl-2 protein (ΔG –7.2 kcal/mol). Both scoping review and molecular docking revealed that quercetin is a promising candidate for anticancer agent.
Investigating the nonlinear dynamics of photosensitive Belousov–Zhabotinsky gels via bifurcation analyses
Authors: Rajput Vandana , Dayal Pratyush
Published: September 2024

Controlling the dynamics of active stimuli-responsive smart materials is essential to replicate the biomimetic functionalities at different length scales for a variety of biological systems-based applications. Photosensitive Belousov–Zhabotinsky (BZ) gels, powered by a nonlinear chemical oscillator, called a BZ reaction are one of the stimuli-responsive smart materials in demand due to their ability to continuously transduce chemical oscillations into mechanical deformations. The chemical oscillations in a BZ reaction and subsequent mechanical oscillations in photosensitive BZ gels occur due to the redox cycle of photosensitive ruthenium complex-based catalysts. In this work, our objective is to identify how the behavior of photosensitive BZ gels can be tuned and used for biomimetic applications by investigating its dynamical characteristics using bifurcation analyses. Specifically, we use the normal form approach and perform linear and nonlinear stability analyses to identify high-order bifurcations by computing higher-order Lyapunov and frequency coefficients. We revealed the existence of domains that encompass coexisting stable and unstable limit cycles (LCs), which merge to form a semi-stable LC at the limit point of cycle (LPC). Their existence shows how a slight variation in the BZ gel recipe can significantly alter its dynamics. Subsequently, we quantify the amplitude and frequency of oscillations in different domains under the effect of variation of BZ reaction formulations. We believe that the outcomes of our work serve as an efficient template for the design and control of BZ gel-based applications. The usage of a normal form and a systematic representation of nonlinear dynamics allow our framework to be extended for other nonlinear dynamical systems.
An exact analytical solution for the weakly magnetized flow around an axially symmetric paraboloid, with application to magnetosphere models
Authors: Kleimann Jens , Röken Christian
Published: September 2024

Rotationally symmetric bodies with longitudinal cross sections of parabolic shape are frequently used to model astrophysical objects, such as magnetospheres and other blunt objects, immersed in interplanetary or interstellar gas or plasma flows. We discuss a simple formula for the potential flow of an incompressible fluid around an elliptic paraboloid whose axis of symmetry coincides with the direction of incoming flow. Prescribing this flow, we derive an exact analytical solution to the induction equation of ideal magnetohydrodynamics for the case of an initially homogeneous magnetic field of arbitrary orientation being passively advected in this flow. Our solution procedure employs Euler potentials and Cauchy's integral formalism based on the flow's stream function and isochrones. Furthermore, we use a particular renormalization procedure that allows us to generate more general analytical expressions modeling the deformations experienced by arbitrary scalar or vector-valued fields embedded in the flow as they are advected first toward and then past the parabolic obstacle. Finally, both the velocity field and the magnetic field embedded therein are generalized from incompressible to mildly compressible flow, where the associated density distribution is found from Bernoulli's principle.
Lax integrability and nonlinear dispersive wave phenomenon for the (3 + 1) dimensional Kudryashov–Sinelshchikov equation
Authors: Chen Wenxia , Ni Weixu , Tian Lixin
Published: September 2024

A (3 + 1) dimensional Kudryashov–Sinelshchikov equation is investigated in this paper, which describes bubbles in the liquid fluctuations. By virtue of the binary Bell polynomials, the bilinear representation, bilinear Bäcklund transformation with associated Lax pair are obtained, respectively. Moreover, utilizing Hirota’s bilinear representation, four new lump solutions are constructed and the interaction phenomenon between lump and periodic solution is thoroughly examined. The work also illustrates the intriguing dynamical behavior with the aid of Maple software, which plots the three-dimensional surface, two-dimensional density, and contour profiles of the solutions constructed in this work in various planes.
Measurement and assignment of J = 5 to 9 rotational energy levels in the 9070–9370 cm−1 range of methane using optical frequency comb double-resonance spectroscopy
Authors: Hjältén Adrian , Silva de Oliveira Vinicius , Silander Isak , Rosina Andrea , Rey Michael , Rutkowski Lucile , Soboń Grzegorz , Lehmann Kevin K. , Foltynowicz Aleksandra
Published: September 2024

We use optical–optical double-resonance spectroscopy with a continuous wave (CW) pump and a cavity-enhanced frequency comb probe to measure the energy levels of methane in the upper part of the triacontad polyad (P6) with higher rotational quantum numbers than previously assigned. A high-power CW optical parametric oscillator, tunable around 3000 cm−1, is consecutively locked to the P(7, A2), Q(7, A2), R(7, A2), and Q(6, F2) transitions in the ν3 band, and a comb covering the 5800–6100 cm−1 range probes sub-Doppler ladder-type transitions from the pumped levels with J′ = 6 to 8, respectively. We report 118 probe transitions in the 3ν3 ← ν3 spectral range with uncertainties down to 300 kHz (1 × 10−5 cm−1), reaching 84 unique final states in the 9070–9370 cm−1 range with rotational quantum numbers J between 5 and 9. We assign these states using combination differences and by comparison with theoretical predictions from a new ab initio-based effective Hamiltonian and dipole moment operator. This is the first line-by-line experimental verification of theoretical predictions for these hot-band transitions, and we find a better agreement of transition wavenumbers with the new calculations compared to the TheoReTS/HITEMP and ExoMol databases. We also compare the relative intensities and find an overall good agreement with all three sets of predictions. Finally, we report the wavenumbers of 27 transitions in the 2ν3 spectral range, observed as V-type transitions from the ground state, and compare them to the new Hamiltonian, HITRAN2020, ExoMol, and the WKMLC line lists.