bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of transcription factors and chromatin modifiers in driving lineage reprogramming in treatment-induced neuroendocrine prostate cancer
Authors: Sreekumar Amritha , Saini Sharanjot
Published: January 2023

Therapy-induced neuroendocrine prostate cancer (NEPC) is a highly lethal variant of prostate cancer that is increasing in incidence with the increased use of next-generation of androgen receptor (AR) pathway inhibitors. It arises via a reversible trans-differentiation process, referred to as neuroendocrine differentiation (NED), wherein prostate cancer cells show decreased expression of AR and increased expression of neuroendocrine (NE) lineage markers including enolase 2 (ENO2), chromogranin A (CHGA) and synaptophysin (SYP). NEPC is associated with poor survival rates as these tumors are aggressive and often metastasize to soft tissues such as liver, lung and central nervous system despite low serum PSA levels relative to disease burden. It has been recognized that therapy-induced NED involves a series of genetic and epigenetic alterations that act in a highly concerted manner in orchestrating lineage switching. In the recent years, we have seen a spurt in research in this area that has implicated a host of transcription factors and epigenetic modifiers that play a role in driving this lineage switching. In this article, we review the role of important transcription factors and chromatin modifiers that are instrumental in lineage reprogramming of prostate adenocarcinomas to NEPC under the selective pressure of various AR-targeted therapies. With an increased understanding of the temporal and spatial interplay of transcription factors and chromatin modifiers and their associated gene expression programs in NEPC, better therapeutic strategies are being tested for targeting NEPC effectively.
Use of fluorescence imaging to optimize location of tissue sampling in hard-to-heal wounds
Authors: Serena Thomas E. , Snyder Robert J. , Bowler Philip G.
Published: January 2023

Introduction

Wound microflora in hard-to-heal wounds is invariably complex and diverse. Determining the interfering organisms(s) is therefore challenging. Tissue sampling, particularly in large wounds, is subjective and, when performed, might involve swabbing or biopsy of several locations. Fluorescence (FL) imaging of bacterial loads is a rapid, non-invasive method to objectively locate microbial hotspots (loads >104 CFU/gr). When sampling is deemed clinically necessary, imaging may indicate an optimal site for tissue biopsy. This study aimed to investigate the microbiology of wound tissue incisional biopsies taken from sites identified by FL imaging compared with sites selected by clinical judgment.

Methods

A post hoc analysis of the 350-patient FLAAG wound trial was conducted; 78 wounds were included in the present study. All 78 wounds were biopsied at two sites: one at the center of the wound per standard of care (SoC) and one site guided by FL-imaging findings, allowing for comparison of total bacterial load (TBL) and species present.

Results

The comparison between the two biopsy sites revealed that clinical uncertainty was higher as wound surface area increased. The sensitivity of a FL-informed biopsy was 98.7% for accurately finding any bacterial loads >104 CFU/g, compared to 87.2% for SoC (p=0.0059; McNemar test). Regarding species detected, FL-informed biopsies detected an average of 3 bacterial species per biopsy versus 2.2 species with SoC (p < 0.001; t-test). Microbial hotspots with a higher number of pathogens also included the CDC’s pathogens of interest.

Conclusions & perspective

FL imaging provides a more accurate and relevant microbiological profile that guides optimal wound sampling compared to clinical judgment. This is particularly interesting in large, complex wounds, as evidenced in the wounds studied in this post hoc analysis. In addition, fluorescence imaging enables earlier bacterial detection and intervention, guiding early and appropriate wound hygiene and potentially reducing the need for antibiotic use. When indicated, this diagnostic partnership with antibiotic stewardship initiatives is key to ameliorating the continuing threat of antibiotic resistance.
COVID-19 telephone contact tracing in Flanders as a “contested” new genre of conversation: Discrepancies between interactional practice and media image
Authors: Bafort Anne-Sophie , De Timmerman Romeo , Van de Geuchte Sofie , Slembrouck Stef , Vandenbroucke Mieke
Published: January 2023

During the COVID-19 pandemic in Belgium, most COVID-19-related information was communicated to the public through mainstream media such as newspaper outlets, television, and radio. These media had substantial influence over which information was (widely) distributed and how this information was framed, subsequently shaping citizens' interpretations of matters concerning the pandemic. This chapter considers one of the government's endeavors to contain the pandemic: COVID-19 telephone contact tracing. Specifically, we compare the image of such telephone contact tracing generated by the media with the de facto interactional practice. We report on analyses made as part of a 1 year applied conversation analytic and pragmatic study conducted at Ghent University and the University of Antwerp in collaboration with the Flemish Agency of Health and Care. Methodologically, we use thematic content analysis to examine the portrayal of COVID-19 telephone contact tracing in widespread Flemish newspapers and its evolution throughout the pandemic. We then compare this media analysis to our analysis of a corpus of 170 recorded, transcribed, and interactionally analyzed contact tracing calls. Our results demonstrate how the mainstream media's image of contact tracing does not align with the various (interactional) functions of COVID-19 contact tracing calls identified in the study. We argue that this one-sided, distorted image produced by the media may have had considerable consequences for the efficacy of contact tracing, especially because the contact tracing call was a new genre of conversation. It was introduced to the public almost exclusively through mainstream media and, at the same time, its success relied for the most part on citizens' voluntary participation, trust, and willingness to share private information.
Case report: A rare manifestation of vasospasm induced myocardial infarction with ST-segment elevation in a young male patient
Authors: Diečkus Laurynas , Rodevič Greta , Baranauskas Arvydas , Davidavičius Giedrius , Budrys Povilas
Published: January 2023

Background

Minority of acute myocardial infarctions (MI) are caused by a non-atherosclerotic occlusion of the coronary artery. We present a case report, where MI with ST-segment elevation was provoked by a vasospasm, which is a rare aetiological finding.

Case presentation

27-year-old male patient presented to the emergency department because of a sudden onset chest pain radiating to the left arm. The patient underwent percutaneous coronary intervention (PCI) to the right coronary artery (RCA) 3 months ago due to inferior wall MI, however, chest pain episodes kept on recurring at night throughout the whole period after the intervention. During current admission, initial electrocardiogram (ECG) demonstrated ST-segment elevation in leads II, III and aVF. Coronary angiogram revealed diffuse severe narrowing of the right coronary artery, which was relieved with intracoronary administration of nitrates and verapamil. After coronary angiogram patient was given oral long-acting nitrates and verapamil, however, during the following days nocturnal chest pain episodes reoccurred. It was decided to swap verapamil to diltiazem, which led to complete cessation of angina episodes. The patient was discharged in stable condition and symptom free. It was suspected that the first MI was of vasospastic origin, which likely led to unnecessary stenting.

Conclusions

This clinical case has demonstrated the challenges clinician could face in order to correctly diagnose vasospasm-induced MI because of its rare occurrence and highly variable presentation. We strongly suggest using intracoronary nitroglycerine during coronary angiography as a standard practice to avoid a potential diagnostic error and unnecessary stenting. Although, in some cases the reason behind coronary artery spasm (CAS) remains unclear, medical treatment can be very effective for CAS prevention.
Risk for acquired coronary artery disease in genetic vs. congenital thoracic aortopathy
Authors: Dolmaci Onur B. , Ayyildiz Tugay , Poelmann Robert E. , Driessen Antoine H. G. , Koolbergen Dave R. , Klautz Robert J. M. , Lindeman Jan H. N. , Grewal Nimrat
Published: January 2023

Objective

Patients with Marfan syndrome (MFS) and patients with a bicuspid aortic valve (BAV) have a significantly increased risk to develop thoracic aortopathy. Both conditions share many pathophysiological mechanisms leading to aortic complications. Bicuspidy is known to have a low risk for acquired coronary artery sclerosis. The aim of this study is to determine the risk of coronary sclerosis in MFS patients.

Methods

Marfan syndrome patients with an aortic root dilatation, which were surgically treated between 1999 and 2017, were included and matched with BAV and tricuspid aortic valves (TAV) patients based on sex and age. Cardiovascular risk profiles were determined in all three groups. Coronary sclerosis was graded in all patients on coronary imaging (coronary angiography or computed tomography) using a coronary artery scoring method, which divides the coronaries in 28 segments and scores non-obstructive (20–49% sclerosis) and obstructive coronary sclerosis (>49% sclerosis) in each segment.

Results

A total of 90 matched patients (30 within each group) were included. MFS patients showed less cardiovascular risk factors compared to BAV and TAV patients. TAV patients had higher amounts of obstructive coronary sclerosis as compared to BAV patients (p = 0.039) and MFS patients (p = 0.032). No difference in non- and obstructive coronary artery disease (CAD) was found between the MFS and BAV population.

Conclusion

Marfan syndrome and bicuspid aortic valve patients have a significantly lower risk for, and prevalence of CAD as compared to TAV individuals.
Case report: Polyarteritis nodosa as a substrate for a massive myocardial infarction
Authors: Solis-Jimenez Fabio , Gonzalez-Ortiz Araceli , Larios-Lara Juan H. , Castro-Garcia Carlos A. , Arteaga-Chan Eduardo I. , Velazquez-Sanchez Fernando , Vargas-Estrada Jorge L. , Ramirez-Marcano Erika Y. , Garaygordobil Diego Araiza , Briseño De La Cruz Jose L. , Gopar-Nieto Rodrigo , Martinez Daniel Sierra-Lara , Arias-Mendoza Alexandra
Published: January 2023

This report describes a rare case of a global myocardial infarction caused by severe vasospasm of the coronary arteries secondary to the administration of pyridostigmine in a patient with polyarteritis nodosa (PAN). Details about the clinical presentation, the typical electrocardiographic pattern of multivessel disease, the differential diagnoses suspected in the multi-imaging approach, and the treatment of cardiogenic shock are described. The definitive diagnosis of infarction and the histopathological findings compatible with polyarteritis nodosa were made by autopsy.
Case report: Left ventricular perforation caused by right ventricular pacemaker lead
Authors: Huang Xiang , Zhou Heng , Li Xiao-Mei , Li Xiao-Lan
Published: January 2023

Background

Perforation of the interventricular septum and left ventricular (LV) free wall by a right ventricular (RV) lead is an extremely rare and potentially life-threatening complication. In this case report, we discussed the diagnosis and management of a very unusual complication of pacemaker (PM) implantation, i.e., LV perforation brought on by an RV pacing lead.

Case summary

A 92-year-old man was admitted to Xiangyang No.1 People’s Hospital due to a complete atrioventricular block. We performed a dual-chamber PM implantation; however, on the second postoperative day (POD), pacemaker failure occurred. Thoracic computed tomography (CT) scan showed that RV lead had pierced the interventricular septum and LV free wall. A transvenous lead extraction of the penetrating lead was performed uneventfully, and RV lead was refixed at the lower RV septum on the 5th POD.

Discussion

Identification of high-risk patients is mandatory to prevent this serious complication, and transvenous lead extraction with cardiac surgery backup may be an option.
Predictive effect of different blood lipid parameters combined with carotid intima-media thickness on coronary artery disease
Authors: Yu Bingyan , Wu Ying , Li Wei , Zhou Langping , Lin Yan , Wang Weimian , Li Guang , Zhou Yingling , Hu Xiangming , Li Xiaohong
Published: January 2023

Background

Blood lipids disorder and atherosclerosis are closely related to coronary artery disease (CAD). This study aims to compare different blood lipid parameters combined with carotid intima-media thickness (cIMT) in predicting CAD.

Methods

This was a retrospective study including patients who underwent coronary angiography for highly suspected CAD. Blood samples were taken for lipid profile analysis and cIMT was evaluated by carotid ultrasound. Logistic analysis was used to establish different models of different lipid parameters in predicting CAD. The area under the receiver operating characteristic curve (AUC) was used to examine the predictive value. The optimal lipid parameter was also used to explore the relationship with multi-vessel CAD.

Results

Patients were classified into two groups based on whether CAD existed. Compared with non-CAD patients, the CAD group had higher lipoprotein (a) [Lp (a)], apolipoprotein B/apolipoprotein A, total cholesterol/high-density lipoprotein cholesterol (HDL-C), triglyceride/HDL-C and LDL-C/HDL-C. According to the AUCs, Lp (a) combined with cIMT (AUC: 0.713, P < 0.001) had the best performance in predicting CAD compared to other lipid parameters. High level of Lp (a) was also associated with multi-vessel CAD (odds ratio: 1.41, 95% confidence interval: 1.02–1.95, P = 0.036).

Conclusion

For patients with highly suspected CAD, Lp (a) better improved the predictive value of CAD rather than most of blood lipid indices, especially in the absence of high levels of LDL-C. Lp (a) also can be used to predict the multi-vessel CAD.
Hydrodynamic variations and human activities have influenced sediment fluxes in the pearl river delta since the late holocene
Authors: Yang Xiaoqiang , Wu Shuang , Shang Shentang , Chen Yan
Published: January 2023

Climate change and human activity can both exert a role in the river discharge and sediment load in river deltas when the sea level remains relatively stable. The Pearl River Delta constitutes the metropolitan region of the Guangdong–Hong Kong–Macau Greater Bay Area, and its evolution in the past and future impacts the sustainable development of this region. In this manuscript, a core situated in the northern South China Sea, adjacent to Qiao Island of Zhuhai city in the Pearl River Delta, was selected to investigate the hydrodynamic variation influenced by tropical processes and the sediment flux imposed by human activities. Using paleosecular variations (PSVs) in geomagnetic field correlations constrained by seven radiocarbon ages, an ∼2.5 kyr chronology was provided for core sediments ∼2.8 m in length. The magnetic fabric results suggest that deposition was influenced by the two types of hydrodynamic-weak energy modulated by El Niño–Southern Oscillation (ENSO) activity and higher energy regulated by high-frequency tropical storms. The cyclic variations in the degree of anisotropy of magnetic susceptibility (P) indicate two periodic changes at approximately 300 and 100 years, which were forced by ENSO activity, while the ratio of lineation with foliation (q value) implies a higher energy flow period of 1.3–1.9 kyr, arising from strong tropical storms. Moreover, the high saturation remanence (SIRM) introduces more sediment flux, which is impacted by growing human activity during the period of 1.0–1.6 kyr.
Seismicity-based 3D model of ruptured seismogenic faults in the North-South Seismic Belt, China
Authors: Rong Yilin , Bai Yongliang , Ren Mengjiao , Liang Mingjian , Wang Zhenjie
Published: January 2023

The North–South Seismic Belt produces the most frequent strong earthquakes in the Chinese continental region, such as the MS 8.0 Wenchuan earthquake on 12 May 2008 and Ms 7.0 Lushan earthquake on 20 April 2013. This seismicity results in significant hazards. Fault geometry modeling is crucial for analyzing earthquake preparation and trigger mechanisms, simulating and predicting strong earthquakes, inverting fault slip rates,etc.In this study, a novel method for obtaining geometric models of ruptured seismogenic faults over a large area is designed based on datasets from surface fault traces, fault orientations, focal mechanism solutions, and earthquake relocations. This method involves three steps. 1) An initial model of the fault geometry is constructed from the focal mechanism solution data. This initial model is used to select the earthquake relocation data related to the target fault. 2) Next, a fine model of the fault geometry with a higher resolution than that of the initial model is fitted based on the selected earthquake relocation data. 3) The minimum curvature interpolation method (Briggs, 2012)is adopted to build a 3D model of the subsurface fault geometry according to the three-dimensional coordinates of nodes on all profiles of each fault/segment. Based on this method and data collected in the North–South Seismic Belt, the fine morphologies of different faults along 1,573 transverse profiles were fitted, and a 3D model of 263 ruptured seismogenic faults or fault segments in the North–South Seismic Belt was built using the minimum curvature spatial interpolation method. Since the earthquake number decreases with increasing depth, the model uncertainty increases with increasing depth. Different ruptured faults have different degrees of seismicity, so different fault models may have different uncertainties. The overall fitting error of the model is 0.98 km with respect to the interpreted results, from six geophysical exploration profiles.
Experimental investigation of the effects of the turbulence on the impact force of flash flood
Authors: Gu Haihua , Lei Yu
Published: January 2023

Flash floods cause damage to engineering structures and buildings mainly due to their huge impact force. Scientific investigation of the impact process of flash floods has significant theoretical and engineering implications in ensuring the safety of flood-resistant structures and human life. In this experimental study, the impact pressure and flow velocity in the flow field were measured synchronously using the impact detection system and a particle image velocimetry system in a water channel and the effects of the turbulence structure on the impact process of flash flood were investigated. As shown by the experimental measurements, the large-scale coherent structure in the flow field reached six times the boundary layer thickness. The turbulence and impact force energy spectra were very similar in the low-frequency, large-scale wave band, indicating that the large-scale turbulence structure dominated the impact process. Both the mean and maximum impact pressures increased with the turbulence kinetic energy. An equation for impact force characterization that considers the effects of turbulence and thus was more accurate was given, providing a theoretical basis for the protection of engineering structures from the damage by flash floods.
A numerical study on the effects of a midlatitude upper-level trough on the track and intensity of Typhoon Bavi (2020)
Authors: Wang Hui , Yu Yubin , Xu Hongxiong , Zhao Dajun , Liang Jia
Published: January 2023

The complex interactions between a tropical cyclone (TC) and the midlatitude upper-level trough or cutoff low (sometimes called a cold-core vortex) can lead to an unusual track, such as sudden turning motion, and intensity change of the tropical cyclone, often leading to large forecast errors. In this study, the track and intensity changes of Typhoon Bavi (2020) under the influence of the upper-level trough and the detached cutoff low from its base are investigated based on numerical experiments using the advanced Weather Research and Forecasting (WRF) model. Bavi formed over the western North Pacific between Taiwan and Okinawa Islands on 23 August 2020. Under the influence of an upper-level trough to the north, Bavi initially moved northeastward. As the trough propagated eastward, a cutoff low was detached from the base of the trough on the next day. The downward penetration of the upper-level cutoff low led to a sudden northwestward turning motion of Bavi when it intensified to a severe typhoon and then moved almost due north and made landfall over North Korea. These changes and processes are well captured in a control numerical experiment. In a sensitivity experiment with the mid-latitude upper-level trough removed in the initial conditions, the tropical cyclone moved primarily north-northeastward after 1-day simulation without the sudden northwestward turning. This track change led to an earlier landfall of the storm over South Korea and, thus, an earlier weakening than in the control experiment, which is termed as the indirect effect on the storm intensity due to the change in the tropical cyclone track. The results also show that eddy angular momentum flux convergence associated with the upper-level trough contributed little to the simulated tropical cyclone intensification, while the environmental vertical wind shear is key to the intensity change of Bavi.
Study of the response characteristics of the water–force coupling action of hard coal bodies in steeply inclined coal seams
Authors: Zhang Leiming , Lai Xingping , Bai Rui
Published: January 2023

Study of the pre-blast weakening of hard-top coal water injection is especially important to solve problems related to the low recovery rate of coal resources and frequent dynamic disasters due to the low degree of fragmentation of hard-top coal during high-stage fully mechanized top-coal caving in steeply inclined coal seams. With the application of rock mechanical tests and numerical simulations, this study carries out mechanical property testing on natural and water-saturated coal samples, investigates the effect of moisture on coal sample mechanical properties in meso-scale, and quantifies the degradation of coal samples under moisture due to mollification. It also reveals the interaction between water and acoustic emission signals based on the statistics of acoustic emission count and energy. A numerical model is established to analyze coal sample internal stress distribution features before and after water injection in macro-scale. Moreover, the detailed mitigating measures for top-coal water injection for engineering practice are designed. The results demonstrate that the mechanical properties of coal samples are significantly affected by moisture-induced degradation. The failure and collapse degrees of water-saturated samples are generally larger than those of natural samples. When the water content is higher, the acoustic emission count and energy of the coal sample are smaller—presenting a negative correlation. The internal stress of coal samples before and after water injection differs significantly. When subjected to water, the top-coal stress releases and transfers, and the peak value is significantly reduced. This study has verified in macro- and meso-scales that top coal can be fully weakened under water–force coupling. The findings of this study are of practical significance for safe and efficient mining and provide a reference for presplit weakening of hard-top coal during horizontal sublevel fully mechanized top-coal caving in steeply inclined coal seams.
Adsorption mechanism of shell powders on heavy metal ions Pb2+/Cd2+ and the purification efficiency for contaminated soils
Authors: Bai Bing , Bai Fan , Sun Chenmiao , Nie Qingke , Sun Shuo
Published: January 2023

The adsorption capacity of oyster shell powders (SPs) and the adsorption mechanism of heavy metal ions (HMs; i.e., cadmium ions Cd2+ and lead ions Pb2+) on SPs are discussed by means of adsorption kinetics tests, adsorption-desorption tests, scanning electron microscopy and Fourier transform infrared spectroscopy. The influences of seepage velocity, heavy metal types, and SP addition amount/concentration on the adsorption effect of SPs in the treatment of HMs in laterite as well as quartz sand were analyzed. Studies have shown that i) the adsorption of HMs on SPs can be divided into three stages, i.e., the surface adsorption stage, the internal pore diffusion stage, and the equilibrium stage; ii) with the increase in seepage velocity, the effluent concentration of HMs will slightly increase, and the residual amounts at each section of the column generally decrease rapidly with the increase in migration distance; iii) the increase in the concentration of SP solution provides more adsorption points for the adsorption of HMs, and finally, the amount of HMs desorbed from quartz sand is reduced, which also reduces the concentration of HMs in the effluent. Overall, SPs possess high purification efficiency for the HMs of contaminated soils.
Late Guadalupian–early Lopingian marine geochemical records from the Upper Yangtze, South China: Implications for climate-biocrisis events
Authors: Li Ruixuan , Sun Shi , Xia Wenpeng , Chen Anqing , Ogg James G. , Yang Shuai , Xu Shenglin , Liao Zhiwei , Yang Di , Hou Mingcai
Published: January 2023

Major paleoenvironmental changes occurred during the Guadalupian-Lopingian boundary (GLB) transition, but the causative linkages among the Emeishan Large Igneous Province (LIP), end-Guadalupian crisis and climatic fluctuations are still in dispute. Variation of geochemical proxies preserved in the sedimentary records is important evidence in examining potential links between volcanisms and environmental changes. Herein, we carried out a comprehensive study of carbon/strontium isotope and trace element geochemistry at the Dukou section, northern margin of the Upper Yangtze. During the Late Guadalupian, the carbon isotope showed a negative drift, the marine primary productivity declined simultaneously, and redox proxies indicate the enhancement of ocean oxidation. It is worth noting that the δ13Ccarb turns into a rapid negative drift from a slow decline at approximately 260.55 Ma, which was almost synchronized with the latest reported eruption ages of Emeishan Large Igneous Province. This coincidence suggests that global volcanic-tectonic activity during the Late Guadalupian might have been the important factor in carbon-cycle perturbation. Subsequently, the δ13Ccarb presents a rapid positive shift at approximately 259.4 Ma, and climate transformed from interglacial to P4 glacial, indicating that the climate rapidly cooled before the Emeishan LIP completely ended, which may be due to carbon sinks caused by weathering of mafic rocks, and may also be associated with a significant reduction in global volcanic activity. Accompanied by sudden weathering attenuation, the 87Sr/86Sr ratios show a significant increase instead from the previous long-time low value, which only can be explained reasonably by the rapid decline in mantle-derived Sr flux associated with the weakening of volcanic activity and mafic weathering. Intergrated geochemical indices in this interval shows that there is a rapid climate perturbation associated with a significant δ13Ccarb negative shift at approximately 260.55 Ma ∼ 259.10 Ma, which may be related to the eruption surge of the Emeishan LIP, active volcanic arcs, and triggered the end-Guadalupian biocrisis.
Multi-scale characteristics of an extreme rain event in Shandong Province, produced by Typhoon Lekima (2019)
Authors: Gao Yue , Zhang Yi , Lei Lili , Tang Jie
Published: January 2023

Super Typhoon Lekima (2019) is the fifth strongest typhoon to make landfall in mainland China since 1949. After its landfall, Typhoon Lekima moved northward along the coastline, resulting in an extreme rain event in Shandong Province that caused the highest precipitation in available meteorological records. A Weather Research and Forecasting (WRF) model simulation that properly produces the track and intensity of Typhoon Lekima and the spatio-temporal evolution of rainfall is used to analyze the multi-scale characteristics of the extreme rain event. The results show that different from the typhoon precipitation which occurred at low latitudes, the extreme rain event that occurred in mid-latitudes was influenced by the interactions of mid-latitude synoptic systems and typhoon circulation, especially with five mesoscale rainbands. The mid-latitude synoptic systems, mainly including the upper-tropospheric jet, the western North Pacific subtropical high, the mid-latitude trough, the low-level jets, and Typhoon Krosa (2019), allowed Typhoon Lekima to maintain its intensity after landfall and provided favorable kinematic, thermodynamic, and moisture conditions for the heavy rainfall in Shandong. Based on the evolution of the mesoscale rainbands, the extreme rain event can be divided into three stages. The first stage can be classified as distant rainfall, which was affected by two convective rainbands associated with boundary-layer processes. The second stage had the highest precipitation, featuring the formation of a frontal zone in Shandong, interacting with Typhoon Lekima. The third stage had weakened rainfall and was directly influenced by the spiral rainband of Typhoon Lekima.
Key stage and model of hydrocarbon accumulation of Ordovician reservoir in Gucheng area, Tarim Basin, China
Authors: Zhang You , Li Qiang , Niu Yongbin , Li Bin , Shi Yanqing , Pang Yumao
Published: January 2023

The heterogeneity of deep carbonate reservoirs is strong, it is significant for exploration and development to clarify the key stages of oil and gas accumulation. Taking the Ordovician in the Gucheng area of Tarim Basin as an example, this paper systematically investigated the key stage and model of hydrocarbon accumulation using the data of the cores, thin sections, cathode luminescence tests, laser ablation U-Pb isotope geochronometry, bitumen reflectance, and fluid inclusion tests, and seismic interpretation. (1) The Tarim Basin mainly develops three sets of effective source rocks, namely the Cambrian Yuertusi Formation, Cambrian Moheershan Formation, and Mid-Lower Ordovician Heituwa Formation, which are concentrated in the slope-basin facies of eastern Tarim Basin. (2) The Gucheng area is located in a favorable paleo-structural position. The pathway system composed of vertical faults and lateral unconformities occurs in the paleo-uplift, which is critical for hydrocarbon migration and accumulation. (3) The laser in-situ U-Pb dating, distribution and genesis of reservoir bitumen, burial-thermal maturation history, and the homogenization temperature of fluid inclusions suggest that the multi-stage tectonic thermal events of the Caledonian and Hercynian stages result in key adjustment and modification to deep hydrocarbon accumulation. Due to magmatic hydrothermal activities, the Caledonian primary oil reservoir massively evolved into oil-cracking gas reservoirs and residual paleo-oil reservoirs. (4) The paleo tectonic-fluid effect plays an important factor controlling the development of the Ordovician reservoirs. The evolution of the hydrocarbon accumulation in Gucheng area can be divided into three stages, namely formation of primary oil and gas reservoirs, oil-cracking gas reservoirs, and adjustment, destruction and reforming of gas reservoirs. To sum up, the western and northern parts of the paleo-uplift with favorable source-reservoir-cap rock assemblage and less effects of hydrothermal activities are the favorable zones for hydrocarbon exploration in the Gucheng area, the Tarim Basin.
Study on reservoir characteristics, pore-throat structure, and origin of tight oolitic reservoirs: A case study of Triassic Feixianguan Formation, NE Sichuan Basin, SW China
Authors: Ren Guanxiong , Qin Qirong , Zhang Qiang , Guo Yanbo , Ye Zhaoyang
Published: January 2023

The origin and pore-throat structure of different lithofacies are key issues in exploration and development of tight oolitic reservoirs. Based on core and thin section observation, four types of lithofacies can be recognized in the Feixianguan Formation oolitic reservoir: 1) oolitic limestone with intergranular pores (Lithofacies A), 2) oolitic limestone with mold pores (Lithofacies B), 3) oolitic dolostone (Lithofacies C), and 4) silty crystalline dolomite and fine crystalline dolostone (Lithofacies D). The subsurface core samples from the different lithofacies were studied using mercury injection, 3D CT scanning, and nuclear magnetic resonance, indicating that Lithofacies D possesses the best pore-throat structure and reservoir connectivity. The pore-throat structure of Lithofacies C is very similar to that of D, but the heterogeneity is much stronger. By comparison, the pore-throat structure of Lithofacies A and B is relatively poor. Although the pore heterogeneity of Lithofacies B is weaker than that of Lithofacies A, there is no effective throat connection in Lithofacies B. On the basis of oolitic shoal deposition, the factors controlling the origin of different lithofacies are meteoric freshwater leaching and then dolomitization. Meteoric freshwater leaching dominates the origin of Lithofacies B but does not affect the origin of Lithofacies C. Lithofacies C is jointly controlled by seepage-reflux and hydrothermal dolomitization fluids. The origin of Lithofacies D is only controlled by seepage-reflux dolomitization. Some other diagenesis effects may also have an impact on petrophysical properties of different lithofacies, but they do not play a decisive role in the origin of different lithofacies.
A new method for estimating multi-source water supply considering joint probability distributions under uncertainty
Authors: Wei Chenxi , Wang Xuan , Fang Jiajia , Wang Zhijing , Li Chunhui , Liu Qiang , Yu Jingzhi
Published: January 2023

A new method integrating techniques of copula and interval estimation to estimate multi-source water supply was proposed. Using the copula theory, joint probability distributions of multiple water sources were constructed for the estimation of water supply. In addition, the interval estimation was used to obtain the interval of water supply under uncertainty for the formulation of water-diversion strategies and the efficient allocation of water resources. This method can give an in-depth investigation on correlations and synchronous–asynchronous characteristics of runoff variations for multiple water sources, thus solving the uncertainty problem of water supply. To demonstrate its applicability, the method was applied to a case study in the Xiong’an New Area, a future metropolis in North China. The results showed that log-normal distributions for the marginal distributions of source 2 (i.e., the Water Diversion Project from the Yellow River to Baiyangdian Lake) and source 3 (i.e., the South-to-North Water Diversion Project) were feasible. The combined channel source, composed of source 2 and source 3, provided [5.20, 12.10] × 108 m3, and reservoir source provided [0.76, 3.60] × 108 m³ of water resources to the Xiong’an New Area per year. Furthermore, without the implementation of multi-source combined water supply pattern in the Xiong’an New Area, there would be a large water supply deficit. This research can provide effective practical suggestions and guidance on water-resource planning and management.
Geochemistry and zircon U–Pb ages of early Ordovician syenites from the Inexpressible Island, Antarctica and tectonic implications
Authors: Gao Peng , Tang Limei , Chen Ling
Published: January 2023

The Ross Orogenic Belt is in the Antarctica Transantarctic Mountains. North Victoria Land Granite Harbour Intrusive complex (GHI) records the tectonic-magmatism evolution of Ross orogeny. Extensively developed post-collisional granites around this margin of early Paleozoic magmatism can provide insights into the growth of continental crust through accretionary orogenesis. We provide geochemical and geochronological data from syenites from Terra Nova Bay, north Victoria Land in order to constrain its tectonic evolution and setting. The syenite belongs to the potassium-alkaline, calc-alkaline series and is characterized by high concentrations of rare Earth elements and large ion lithophile elements (LILE), and low content in high field strength elements (Nb, Ta, P, Ti). The petrographic and geochemical signatures show a possible island-arc granite affinity. LA-ICP-MS zircon U-Pb dating results suggest that the Inexpressible Island syenite was emplaced at ca. 471.8 ± 1.8 Ma and 477.3 ± 1.7 Ma, respectively. Zircon εHf(t) values range from −7.4 to −9.1; average −8.2 and whole-rock εNd (t) values range from −8.5 to −10.3, indicating that formed by the partial melting of the lithospheric mantle enriched with subduction slab fluids and subcontinental lithosphere. Whereas, the syenite has a strong positive Eu anomaly and a positive Sr anomaly, suggesting that plagioclase cumulate crystallization occurred in the magma source area. Furthermore, through integration with previous studies, we suggest that syenite is a result of the melting zone of an older previously subduction enriched layer of the subcontinental lithospheric mantle (SCLM). To enable syenite emplacement we suggest a tectonic-magmatic model that invokes alternating phases of extension and contraction in the overriding plate. Finally, we report the youngest age of (post-orogenic) magmatism occurred during extension in the overriding plate ca. 478–471 Ma.
Influence mechanism of confining pressure on the hydraulic aperture based on the fracture deformation constitutive law
Authors: Feng Peichao , Ma Haichun , Wang Jingping , Qian Jiazhong , Luo Qiankun
Published: January 2023

The confining pressure induces the deformation of fractures with seepage through the fracture. The seepage characteristics can reflect the deformation of the hydraulic aperture. We propose theoretical models to describe the mechanism by which the confining pressure influences the hydraulic aperture based on the fracture deformation constitutive law models of Goodman, Bandis, Sun, and Rong. Hydromechanical testing data were used to validate the four types of proposed models. The experiment results reveal the confining pressure and hydraulic aperture model based on Sun’s exponential model describes the mechanism the best. The maximum hydraulic aperture closure deformation and initial hydraulic aperture go through a growth phase with a decreasing rate, and then, they enter a stability phase when the flow rate increases to 7 ml/min, while the normal stiffness of the fracture decreases to a certain value and then tends to a stable value. Flow rate decreases as confining pressure increases in a nonlinear progression, which is described by Sun’s exponential model well. We further found that in laboratory tests at various temperatures and in field tests, the confining pressure’s influence on the hydraulic aperture is highly consistent with the model based on Sun’s model. The model developed in this study describes the mechanism by which the confining pressure influences the hydraulic aperture, and it is meaningful to rock seepage engineering with in situ stress changes at different temperatures.
Study on the underpinning mechanisms of microwave-induced synthesis of carbon-coated metal nanoparticles
Authors: Jia Pingshan , Sun Jing , Wang Wenlong , Song Zhanlong , Zhao Xiqiang , Mao Yanpeng
Published: January 2023

Microwave-induced metal arc discharge provides an intriguing solution for the synthesis of carbon-coated metal nanoparticles (M@CNPs) due to its fast formation and improved quality of products, however, the underpinning reaction mechanism is not comprehensively revealed. In this work, the effect of arc discharge intensity on the product morphology is firstly investigated by adjusting microwave power. And then, the effects of the organic groups (i.e. cyclopentadienyl v. s Acetylacetonate groups) and metal catalysis on the product morphology are also investigated by selecting ferrocene, iron acetylacetonate, nickelocene, and nickel acetylacetonate as precursors. Specifically, moderate microwave power can not only destroy the precursor to form carbon nanosheets by inducing intense discharge heat release but also provide sufficient intermittency to allow the carbon nanosheets to deposit on the surface of the metal core, which is an important precondition in fabricating M@CNPs. The structure of organic groups in the precursor also plays a predominant role in adjusting product morphology. Cyclopentadienyl groups tend to encapsulate the metal core to form graphitized carbon shells as the coordination bond between cyclopentadienyl and metal is recognized as a very strong covalent bond that confines the cyclopentadienyl collapse to metal core, and the cyclic structure facilitates the formation of graphite. In contrast, the acetylacetonate groups intend to combine randomly due to their open-loop structure. Moreover, for open-loop structures such as acetylacetonate groups, metal catalysis also affects the growth trend, of which Ni is more likely to induce the formation of carbon nanotubes relative to Fe. This work can provide a good reference for the synthesis of M@CNPs with controllable morphology.
Trade network characteristics, competitive patterns, and potential risk shock propagation in global aluminum ore trade
Authors: Wang Yue , Chen Lu , Wang Xiaoyi , Tang Nan , Kang Xinyu
Published: January 2023

Aluminum is an essential strategic mineral resource. The geographical space distribution characteristics make the aluminum ore trade relationship more complicated. This paper analyzes the evolution characteristics, spatial migration, and trade competition of aluminum ore trade from 2011 to 2020. This paper constructs the aluminum supply risk propagation network Aluminum Supply Risk Spread Network to analyze the propagation path, impact scope, and potential impact of different risk outbreak sources. The results show that a few countries control more aluminum ore resources, and the trade community and center of trade gravity have changed significantly. Trade competition gradually intensifies, mainly concentrated in Asia and Europe. When supply risk occurs, the threat spreads rapidly. This paper selects four major trading countries Brazil, Guinea, Australia, and China, as risk outbreak countries. Risk outbreak mainly shows three typical characteristics. Meanwhile, indirect infections account for a large proportion, and China plays an essential role in trade. Finally, based on these findings, some suggestions to maintain the stability of the aluminum resource trade and improve its ability to resist risks for China.
Curve and double-layer economic dispatching considering reasonable wind abandonment under different time granularities
Authors: Gang Zhang , Yue Yang , Tuo Xie , She Zhang Kao , Xin He
Published: January 2023

In view of the large output of wind power during the load trough time, the peak regulation cost may increase sharply, and the traditional hourly dispatch may not be able to accurately track the load fluctuation due to the fluctuation of renewable energy. In this paper, based on different time granularities, an adaptive segmented double-layer economic scheduling model of the net load curve considering reasonable wind abandonment is constructed. The model can better cope with net load changes while reducing the load peak-to-valley difference. First, a reasonable wind abandonment model is established under different time granularities of 5 min, 15 min, 30 min, and 1 h; Then, based on the static thinking of the net load curve by time period, the load change in the hourly scale is fully considered without changing the total number of dispatching periods so that each dispatching period can adaptively select the duration according to the change of net load gradient, and a self-adaptive subsection model of the net load curve is established to minimize the total running cost. Finally, taking IEEE-30 nodes as the example system, the NSGA-II algorithm and CPLEX solver are used to solve the model. The results verify the economy and feasibility of the proposed model.
CE-SDT: A new blockchain-based distributed community energy trading mechanism
Authors: Wang Bozhi , Xu Jinfei , Ke Jin , Chen C. L. Philip , Wang Junyu , Wang Nanxin , Li Xi , Zhang Fangfei , Li Lulu
Published: January 2023

With the spread of distributed renewable energy, residents are shifting from being mere consumers to being energy producers and consumers. This role shift poses challenges to the electricity trading mechanism that connects distributed renewable energy sources to the grid. In this paper, a new efficient and secure blockchain-based distributed community energy trading mechanism is proposed, called CE-SDT. Our system is proved to be stable and scalable. It can also help shift loads and power peaks and reduce customer costs by 60%. As a result, our proposed blockchain-based trading mechanism, as compared to the centralized trading mechanism, is applied to microgrids formed by distributed renewable energy sources, not only obtaining greater economic benefits but also reducing the carbon footprint of residents, and furthermore, it promotes low or zero-carbon configurations of the power system, thereby achieving certain environmental benefits.
Numerical investigation of cooling ability in heat-generating porous debris bed after severe accident in PWR
Authors: Xu Junying , Dong Xiaomeng , Zhang Huiyong , Yun Xiangyu , Zhang Lei , Ye Yuzhao , Liu Xiang , Mo Jinhong , Yang Ming
Published: January 2023

A porous debris bed formed after a severe accident is a structure composed of different sized particles. Due to the fission reaction in the debris bed, decay heat is continuously released. Therefore, the cooling ability should be investigated to determine the safety of the debris bed. In this paper, two-phase conservation equations with closure correlations are proposed for the boiling phenomenon inside the pool. For the flow resistance, the drag force between the gas and liquid in the continuous fluid is considered as well as the flow resistance of the solid to fluid in the porous medium area. The heat transfer model takes into account the heat transfer between solid phase and fluid phases as well as the heat and mass transfer between gas and liquid. All calculations are conducted based on the CFD method, and the related models are written into the CFD calculation program in the form of a User Defined Function (UDF). After the necessary validation of the proposed correlations, the analysis and discussion are based on the effect of the heating type, the non-uniform distribution of structural parameters, and the shape of the geometry. The results show the key effect of natural convection between the different boundary settings of the heating type. The time series of strong natural convection formation and the decay power of heat are the factors that are determined for the position of the boiling crisis. In addition, the limited power density is determined by the top half of the debris bed. The increase in structural parameters and operating pressure leads to a better cooling ability. For the shape of the debris bed, a regular cylinder is a better structure for heat removal, while the conical shape significantly reduces the limited power density, which is dangerous for the long-term cooling of the debris bed. The cooling ability would be improved if a downcomer existed in the porous debris bed. These three research parts are conducive to deepening the understanding of the process of a serious accident.