bluuebunny/crossref_metadata_2025 huggingface dataset:
Therapeutic RNA regulation during cardiac remodeling and disease
Authors:   , Vigil Garcia Marta
Published: January 2023

Cardiovascular diseases (CVDs) are diseases that affect the heart and blood vessels and to date, there is no cure. The only available clinical practices to manage CVDs are suggesting lifestyle changes, exercise-based cardiac rehabilitation, symptom management with medication, surgical intervention to prevent sudden cardiac arrest, or heart transplantation in case of end-stage heart failure. In this thesis we performed studies to extend our knowledge on 1) cardiac-specific gene regulation pathways relevant during CVDs and 2) new therapeutic approach to deliver pharmacological agents in the heart cells to treat ischemic heart disease. To do so, we sequenced the RNA of cardiomyocytes isolated from mouse models of cardiac pathological and physiological hypertrophy, we used in vitro cardiac models to identify and investigate the role of novel gene targets. Additionally, we studied the safety and efficacy of a hydrogel-based delivery method to increase local delivery of miRNA therapeutics to cardiomyocytes in a mouse model of ischemic heart disease. Our results showed that cardiomyocytes at various stages of cardiac remodeling present remarkably diverse genetic profiles and that these genetic profiles have a potentially relevant role in regulating heart remodeling, from metabolic switch to transcription factors to miRNAs. At therapeutic level, we show that we can intervene using RNA therapeutics and hydrogel-based delivery.
Thesis outline
The studies described in this thesis were aimed to extend our insights on CM-specific gene regulation relevant for cardiac remodeling and to study a novel therapeutic approach for CM-specific delivery.
In chapter 2 we investigate CM-specific gene programs in pathological remodeling. Using a model of pressure overload, we identified a failure-induced gene program, which is conserved between mouse and human. Here, we identified phosphofructokinase-platelet isoform (PFKP) to play a role in CM remodeling during HF.
In chapter 3 we investigate CM-specific gene programs driving physiological hypertrophy. Using a model of swimming, we identified the exercise-induced gene program in CMs. By focusing on transcription factors, we identified high expression of Sox17 in hypertrophic CMs. We investigated the potential cardioprotective role of Sox17 in a model of pressure overload by using adenoviral delivery which failed to preserve cardiac function during pathology.
In chapter 4 we investigate the efficacy and safety of a new hydrogel-based delivery system in a model of ischemic injury. Hydrogel-based delivery of antimir-195 improved CM local delivery and enhanced target de-repression and CM proliferation.
Finally, in chapter 5 we discuss all findings in a broader context together with future perspectives.
Biological carbon pump in the Black Sea
Authors: Silkin Vladimir A. , Podymov Oleg I. , Lifanchuk Anna V.
Published: January 2023

In the northeastern part of the Black Sea, the biological carbon pump is represented by both organic and carbonate pumps. The organic carbon pump consists of small-cell diatoms (mainly Pseudo-nitzschia pseudodelicatissima) and large-cell diatoms (Pseudosolenia calcar-avis and Proboscia alata). The carbonate pump is represented by only one species of cococcolithophore, Emiliania huxleyi. These species form intense blooms that require characteristic hydrological and hydrochemical conditions. The seasonal dynamics of the biological carbon pump is as follows: organic pump (spring) → carbonate pump (late spring and early summer) → organic pump (summer and autumn). An exception is the long-term dynamics of carbon concentration, and no significant carbon growth trends have been identified. During the intensification of the work of the carbonate pump, partial concentrations of carbon in water, increased relative to the atmosphere, and an increased influence of the organic pump on high partial pressure are released. In late spring and early summer, CO2 is released in the Black Sea, as a result, absorption increases in summer. The carbonate pump arises with a greater arrival at sea.
VALUE MEASUREMENTS: CONTENT ANALYSIS IN SOCIAL NETWORKS
Authors:   Institute of Public Service and Management of the RANEPA under the President of the Russian Federation, Moscow, Russian Federation, ILYICHEVA LYUDMILA , SYZDYKOV  ASKAR
Published: January 2023

Social media platforms are becoming important translators of values in modern society, where young people express political sentiments through the use of various types of content. Relatively free online communication platforms, as well as high Internet penetration among young people, make it particularly relevant to study political values through content analysis in social networks. In order to determine the political values of young people that they broadcast on social networks, a comprehensive study was conducted based on the use of case-study, event-analysis and content analysis methods. In total, 42 groups of neutral dialogue platforms were studied; 42 - opposition and 23 communities of the “Young Guard”. Such a sample allows us to identify the peculiarities of the transmission of political values depending on geography, local traditions, peculiarities of mentality, and the development of civic activism.
ENERGY MANAGEMENT AND NEW PARADIGM
Authors: Knoll-Csete Edit
Published: January 2023

Energy management includes the planning and operation of energy-related generation and consumption units. The goals are resource conservation as well as climate protection and cost reductions, while ensuring the energy needs of users. The energy controlling division supports cost- and material-efficient energy and material flow management. The key issue in energy management is a paradigm shift in thinking. Actors in the energy sector are used to the fact that there is a supply market in the energy sources market. The essence of the new paradigm shift to be implemented in energy management can be summed up in the fact that the goal system of the energy policy, which until now has only been aimed at always achieving supply surplus, will fundamentally change. Ultimately, consumers paid all the costs of energy supply management, and this has maximized the high profits of companies operating in the energy sector.
Comprehensive genome-scale metabolic model of the human pathogen Cryptococcus neoformans: A platform for understanding pathogen metabolism and identifying new drug targets
Authors: Tezcan Enes Fahri , Demirtas Yigit , Cakar Zeynep Petek , Ulgen Kutlu O.
Published: January 2023

Introduction: The fungal priority pathogen Cryptococcus neoformans causes cryptococcal meningoencephalitis in immunocompromised individuals and leads to hundreds of thousands of deaths per year. The undesirable side effects of existing treatments, the need for long application times to prevent the disease from recurring, the lack of resources for these treatment methods to spread over all continents necessitate the search for new treatment methods.

Methods: Genome-scale models have been shown to be valuable in studying the metabolism of many organisms. Here we present the first genome-scale metabolic model for C. neoformans, iCryptococcus. This comprehensive model consists of 1,270 reactions, 1,143 metabolites, 649 genes, and eight compartments. The model was validated, proving accurate when predicting the capability of utilizing different carbon and nitrogen sources and growth rate in comparison to experimental data.

Results and Discussion: The compatibility of the in silico Cryptococcus metabolism under infection conditions was assessed. The steroid and amino acid metabolisms found in the essentiality analyses have the potential to be drug targets for the therapeutic strategies to be developed against Cryptococcus species. iCryptococcus model can be applied to explore new targets for antifungal drugs along with essential gene, metabolite and reaction analyses and provides a promising platform for elucidation of pathogen metabolism.
MGMSN: Multi-Granularity Matching Model Based on Siamese Neural Network
Authors: Wang Xin , Yang Huimin
Published: January 2023

Graphical Abstract
Sustained intra-articular reactive oxygen species scavenging and alleviation of osteoarthritis by biocompatible amino-modified tantalum nanoparticles
Authors: Jiang Yunsheng , Li Tao , Yang Junjun , Wang Xin , Song Xiongbo , Chen Guangxing , Dai Gang , Li Rong , Yao Chunyan , Chen Jiajia , Chen Cheng , Gong Xiaoyuan , Yang Liu
Published: January 2023

Recent studies highlight the vital role of oxidative stress and reactive oxygen species (ROS) during progression of osteoarthritis (OA). Attenuating oxidative stress and reducing reactive oxygen species generation in joints represent reasonable strategies for the treatment of osteoarthritis. To address the potential question for clinical translation, and improve the biocompatibility and long-term performance of current antioxidants, the present study provided high biocompatible small positively charged tantalum nanoparticles (Ta-NH2 NPs) with sustained intra-articular catalase activity and first applied to osteoarthritis intervention. Our in vitro results showed that Ta-NH2 NPs were stable with good biocompatibility, and protected viability and hyaline-like phenotype in H2O2-challenged chondrocytes. In addition, the in vivo biodistribution data demonstrated a sustained retention of Ta-NH2 NPs in the joint cavity, particularly in articular cartilage without organ toxicity and abnormality in hemogram or blood biochemistry indexes. Finally, compared with catalase (CAT), Ta-NH2 NPs exhibited long-term therapeutic effect in monosodium iodoacetate (MIA) induced osteoarthritis model. This study preliminarily explored the potential of simply modified metal nanoparticles as effective reactive oxygen species scavenging agent for osteoarthritis intervention, and offered a novel strategy to achieve sustained reactive oxygen species suppression using biocompatible Ta-based nano-medicine in oxidative stress related diseases.
Apocrine secretion in the salivary glands of Drosophilidae and other dipterans is evolutionarily conserved
Authors: Babišová Klaudia , Mentelová Lucia , Geisseová Terézia Klaudia , Beňová-Liszeková Denisa , Beňo Milan , Chase Bruce A. , Farkaš Robert
Published: January 2023

Apocrine secretion is a transport and secretory mechanism that remains only partially characterized, even though it is evolutionarily conserved among all metazoans, including humans. The excellent genetic model organism Drosophila melanogaster holds promise for elucidating the molecular mechanisms regulating this fundamental metazoan process. Two prerequisites for such investigations are to clearly define an experimental system to investigate apocrine secretion and to understand the evolutionarily and functional contexts in which apocrine secretion arose in that system. To this end, we recently demonstrated that, in D. melanogaster, the prepupal salivary glands utilize apocrine secretion prior to pupation to deliver innate immune and defense components to the exuvial fluid that lies between the metamorphosing pupae and its chitinous case. This finding provided a unique opportunity to appraise how this novel non-canonical and non-vesicular transport and secretory mechanism is employed in different developmental and evolutionary contexts. Here we demonstrate that this apocrine secretion, which is mechanistically and temporarily separated from the exocytotic mechanism used to produce the massive salivary glue secretion (Sgs), is shared across Drosophilidae and two unrelated dipteran species. Screening more than 30 species of Drosophila from divergent habitats across the globe revealed that apocrine secretion is a widespread and evolutionarily conserved cellular mechanism used to produce exuvial fluid. Species with longer larval and prepupal development than D. melanogaster activate apocrine secretion later, while smaller and more rapidly developing species activate it earlier. In some species, apocrine secretion occurs after the secretory material is first concentrated in cytoplasmic structures of unknown origin that we name “collectors.” Strikingly, in contrast to the widespread use of apocrine secretion to provide exuvial fluid, not all species use exocytosis to produce the viscid salivary glue secretion that is seen in D. melanogaster. Thus, apocrine secretion is the conserved mechanism used to realize the major function of the salivary gland in fruitflies and related species: it produces the pupal exuvial fluid that provides an active defense against microbial invasion during pupal metamorphosis.
Mesenchymal stem cell-based therapy for female stress urinary incontinence
Authors: Liu Xiaochun , Li Tingting , Zhang Jia , Lin Xiling , Wang Wenzhen , Fan Xiaodong , Wang Lili
Published: January 2023

Stress urinary incontinence (SUI) adversely affects the quality of life of patients, while the currently available surgical and non-surgical therapies are not effective in all patients. Application of mesenchymal stem cells (MSCs) for regaining the ability to control urination has attracted interest. Herein, we reviewed the literature and analyzed recent studies on MSC-based therapies for SUI, summarized recent treatment strategies and their underlying mechanisms of action, while assessing their safety, effectiveness, and prospects. In addition, we traced and sorted the root literature and, from an experimental design perspective, divided the obtained results into four categories namely single MSC type therapy for SUI, MSC-based combination therapy for SUI, treatment of SUI with the MSC secretome, and other factors influencing MSC therapy. Although evidence demonstrates that the treatment strategies are safe and effective, the underlying mechanisms of action remain nebulous, hence more clinical trials are warranted. Therefore, future studies should focus on designing clinical trials of MSC-based therapies to determine the indications for treatment, cell dosage, appropriate surgical strategies, and optimal cell sources, and develop clinically relevant animal models to elucidate the molecular mechanisms underlying stem cell therapies improvement of SUI.
Interstrand crosslinking oligonucleotides elucidate the effect of metal ions on the methylation status of repetitive DNA elements
Authors: Liu Shan , Morihiro Kunihiko , Takeuchi Fumika , Li Yufeng , Okamoto Akimitsu
Published: January 2023

DNA methylation plays an important physiological function in cells, and environmental changes result in fluctuations in DNA methylation levels. Metal ions have become both environmental and health concerns, as they have the potential to disrupt the genomic DNA methylation status, even on specific sequences. In the current research, the methylation status of two typical repetitive DNA elements, i.e., long-interspersed nuclear element-1 (LINE-1) and alpha satellite (α-sat), was imaged and assessed using methylation-specific fluorescence in situ hybridization (MeFISH). This technique elucidated the effect of several metal ions on the methylation levels of repetitive DNA sequences. The upregulation and downregulation of the methylation levels of repetitive DNA elements by various metal ions were confirmed and depended on their concentration. This is the first example to investigate the effects of metal ions on DNA methylation in a sequence-specific manner.
Quantitative analysis of fertilizer using laser-induced breakdown spectroscopy combined with random forest algorithm
Authors: Wei Lai , Ding Yu , Chen Jing , Yang Linyu , Wei Jinyu , Shi Yinan , Ma Zigao , Wang Zhiying , Chen Wenjie , Zhao Xingqiang
Published: January 2023

Chemical fertilizers are important for effectively improving soil fertility, promoting crop growth, and increasing grain yield. Therefore, methods that can quickly and accurately measure the amount of fertilizer in the soil should be developed. In this study, 20 groups of soil samples were analyzed using laser-induced breakdown spectroscopy, and partial least squares (PLS) and random forest (RF) models were established. The prediction performances of the models for the chemical fertilizer content and pH were analyzed as well. The experimental results showed that the R2 and root mean square error (RMSE) of the chemical fertilizer content in the soil obtained using the full-spectrum PLS model were .7852 and 2.2700 respectively. The predicted R2 for soil pH was .7290, and RMSE was .2364. At the same time, the full-spectrum RF model showed R2 of .9471 (an increase of 21%) and RMSE of .3021 (a decrease of 87%) for fertilizer content. R2 for the soil pH under the RF model was .9517 (an increase of 31%), whereas RMSE was .0298 (a decrease of 87%). Therefore, the RF model showed better prediction performance than the PLS model. The results of this study show that the combination of laser-induced breakdown spectroscopy with RF algorithm is a feasible method for rapid determination of soil fertilizer content.
Association between probiotic therapy and the risk of hepatocellular carcinoma in patients with hepatitis B-related cirrhosis
Authors: Shi Ke , Zhang Qun , Zhang Yi , Bi Yufei , Zeng Xuanwei , Wang Xianbo
Published: January 2023

Objective

Probiotics may offer cancer-prevention benefits, based on experimental investigation results. This study aimed to determine the potential association between probiotics and hepatocellular carcinoma (HCC) in patients with hepatitis B-related cirrhosis (HBC) receiving antiviral therapy.

Design

This retrospective study included 1267 patients with HBC treated with entecavir or tenofovir between January 2013 and December 2017. The risk of developing HCC was compared between two cohorts of 449 probiotic users (taking a cumulative defined daily doses [cDDD] of ≥ 28) and 818 non-probiotic users (< 28 cDDD). To eliminate the bias caused by confounding factors, propensity score matching (PSM) was used.

Results

On multivariate regression analysis, probiotic consumption was an independent protective factor for HCC occurrence. After PSM, the incidence of HCC was significantly lower in the probiotic users than that in the nonusers (adjusted hazard ratio [aHR]: 0.70, 95% confidence interval: 0.59–0.83, P < 0.001). The aHRs for probiotics with 28–89, 90–180, and >180 cDDD were 0.58, 0.28, and 0.12, respectively, indicating a dose-response pattern. In 28–89, 90–180, and >180 cDDD, the 3-year cumulative incidence of HCC was 8.7%, 4.7%, and 3.0%, respectively. A multivariate stratified analysis confirmed that the administration of probiotics could help patients.

Conclusion

Adjuvant probiotic therapy may reduce the risk of HCC in patients receiving antiviral medication for HBC. However, further clinical research is required to confirm these findings.
Collective storytelling as a river restoration tool: The role of catchment communities in inspiring environmental change
Authors: Doehring Katharina , Cole Cathy , Young Roger G. , Longnecker Nancy
Published: January 2023

In Aotearoa New Zealand, catchment communities have been actively working to restore the health of their rivers, in some cases for many decades. Their knowledge offers a valuable resource that could motivate and empower other groups to do the same, making river restoration more effective at large scales. We spoke to five catchment groups across Aotearoa New Zealand to conceptualize and define how knowledge sharing through storytelling could be used as a tool to inspire freshwater restoration action amongst their own community and elsewhere. Each group created a “Catchment Journey,” a graphical artwork that told a story of their land and people, and their restoration activities. Whilst each of these “Journeys” was unique, the following common elements were important for knowledge sharing: (1) the role of respected storytellers (e.g., community champions) in influencing restoration in their community; (2) recognition of responsibility to act (e.g., concern for future generations, land stewardship, prosperity and community cohesion); and (3) authenticity (e.g., true and honest stories, including weaknesses, threats and hardship). Participants recommended including each of these key elements in collective catchment storytelling to encourage large scale freshwater restoration.
Identification of pathological-related and diagnostic potential circular RNAs in Stanford type A aortic dissection
Authors: Liang Qiao , Zhou Zeyi , Li Hui , Tao Qing , Wang Yali , Lin Anqi , Xu Jing , Zhang Bin , Wu Yongzheng , Min Haiyan , Wang Lei , Song Shiyu , Wang Dongjin , Gao Qian
Published: January 2023

Introduction

Stanford type A aortic dissection (TAAD) is one of the lethal macrovascular diseases caused by the invasion of blood into the media layer of ascending aortic wall. Inflammation, smooth muscle dysfunction, and extracellular matrix (ECM) degradation were regarded as the major pathology in affected tissue. However, the expression pattern and its regulation especially through circular RNAs (circRNAs) as an overall characteristic of TAAD molecular pathology remain unclear.

Methods

We employed CIRCexplorer2 to identify circRNAs based on the RNA sequencing (RNA-seq) data of human ascending aortic tissues to systematically assess the role of circRNA in the massive alterations of gene expression in TAAD aortas. The key circRNAs were determined by LASSO model and functionally annotated by competing endogenous RNAs (ceRNA) network and co-analysis with mRNA profile. The expression level and diagnostic capability of the 4 key circRNAs in peripheral serum were confirmed by real-time polymerase chain reaction (RT-PCR).

Results

The 4 key circRNAs, namely circPTGR1 (chr9:114341075-114348445[−]), circNOX4 (chr11:89069012-89106660[−]), circAMN1 (chr12:31854796-31862359[−]) and circUSP3 (chr15:63845913-63855207[+]), demonstrated a high power to discriminate between TAAD and control tissues, suggesting that these molecules stand for a major difference between the tissues at gene regulation level. Functionally, the ceRNA network of circRNA-miRNA-mRNA predicted by the online databases, combining gene set enrichment analysis (GSEA) and cell component prediction, revealed that the identified circRNAs covered all the aspects of primary TAAD pathology, centralized with increasing inflammatory factors and cells, and ECM destruction and loss of vascular inherent cells along with the circRNAs. Importantly, we validated the high concentration and diagnostic capability of the 4 key circRNAs in the peripheral serum in TAAD patients.

Discussion

This study reinforces the vital status of circRNAs in TAAD and the possibility of serving as promising diagnostic biomarkers.
Architecture, genesis, and the sedimentary evolution model of a single sand body in tight sandstone reservoirs: A case from the Permian Shan-1–He 8 members in the northwest Ordos Basin, China
Authors: Yang Zhen , Wang Shumin , Chen Jiahao , Jing Shuai
Published: January 2023

A single sand body is defined as a geological unit that is continuous vertically and horizontally but separated from the upper and lower sand bodies by mudstone or impermeable intercalation. The architecture of a single sand body is significant in the determination of hydrocarbon accumulation mechanisms in gas reservoirs, especially for exploitation of multiple tight sandstone gas (TSG) reservoirs. One such example is the gas reservoirs in the Tianhuan Depression, China, where the architecture and genesis of sand bodies are poorly understood. Based on the geologic background and sedimentary characteristics, the evolution of the distributary channel in the Tianhuan Depression has been examined using data from geological outcrops, cores, and well logs. The results showed that sand body architecture depends on the evolution of channel systems, and the scale and size of the channel are controlled by the sedimentary environment. Three kinds of sedimentary microfacies (distributary channel, channel mouth bar, and interdistributary bay) are mainly developed in the study area, and four types of single sand body stacking patterns (isolated, vertically superimposed, laterally tangentially superimposed, and horizontally bridged sand bodies) have formed in such a depositional environment. The target strata (Shan-1 and He-8 members) provide an ideal object for studying the evolution of the river and the architecture of the sand bodies. During the early stage of deposition, the sediment supply was insufficient, with restricted meandering river deltas dominating and sand bodies mostly existing as isolated types. Until the middle period of deposition, the sediment supply suddenly increased, the sedimentation rate accelerated with the decrease in the lake water base level, and the channel evolved into a large-scale braided river delta, generally forming superimposed sand bodies. By the late period of deposition, the provenance supply was reduced again; although braided river delta deposits were still dominant, the channel scale was restricted, and the sand bodies were predominantly isolated and horizontally bridged types. This work establishes a sedimentary evolution model for tight sandstone gas reservoirs, that is, a complete cycle of river evolution from small scale to large scale to terminal weakening, and discusses the genetic mechanism of single sand body architecture in such a depositional model.
Temporally varied coastal uplift rates north of the Littoral Fault Zone since the late Quaternary in the northern South China Sea: Insights from the wave-cut platform and cosmogenic exposure dating
Authors: Liang Hao , Zhang Ke , Li Zhigang , Chen Zhen , Hui Gege , Huang Ping , Tian Qingying , Tang Yongjie , Chen Cong , Zhang Yipeng , He Xiaohui , Yan Yonggang , Dai Xiangming , Li Zhongyun , Wang Weitao , Zhang Peizhen
Published: January 2023

While understanding the long-term slip rate of active normal faults is essential for the comprehensive assessment of seismic activity, it is difficult due to the absence of age control in the erosional bedrock region. The preserved sequence of wave-cut platforms in granite allows exploration of the long-term slip rate in the footwall of some normal faults. We investigated wave-cut platforms in the southern Pearl River Delta (PRD), a coastal delta transected by the seismically active Littoral Fault Zone (LFZ) in the northern South China Sea, to derive slip rates and their impacts on the seismic hazard potential. We mapped a flight of four wave-cut platforms (T1–T4), dated the T2 and T4 platforms by 10Be cosmogenic nuclide dating, and used the absolute age to correlate the un-dated platform to global sea-level highstands. Our results allocate the ages of 128 ka, 197 ka, and 239 ka to the upper three wave-cut platforms and yield temporally various uplift rates ranging from 0.30 to 0.38 mm/a during 239–128 ka to 0.09 mm/a since 128 ka. A decrease in the uplift rate, which coincided with a decreased subsidence rate within the PRD in previous work, implied a weakened differential uplift onshore of the LFZ system. Our findings infer that the transgression event occurred as early as marine isotope stage (MIS) 7 in the PRD, consistent with the view that Pleistocene sedimentation began in MIS 5 or earlier in the PRD.
Quantitative prediction of sand bodies in a sparsely explored zone of the Tarim basin: A case study of the aketao area
Authors: Xiaoqian Shi , Yongqiang Qu , Junfeng Zhou , Wenhao Liu , Juanjuan Guo , Junfa Xie
Published: January 2023

Thin sandstone reservoirs of the fan delta front sub-facies occur in the early Neogene (Miocene) series of the Aketao (Akto) structural belt within the Kunlun piedmont zone of the Tarim Basin. Oil and gas reservoirs in this area correspond to stratigraphic traps. However, owing to the low density of the 2D seismic survey grid deployed in the Aketao belt, inferior seismic data quality, and lack of well logging data, reservoir prediction in this area suffers from a multiplicity of problems and it is difficult to effectively identify sand bodies. Here, a new research approach is proposed involving the use of 3D seismic, well logging, and drilling data from a neighboring highly-explored 3D seismic survey area as a reference for the 2D seismic interpretation of the non-drilled Aketao survey area. Moreover, this approach is integrated with forward modeling and the inversion of post-stack seismic data to identify sand bodies. A comparison of the seismic reflection characteristics clarifies that these 3D and 2D seismic survey areas share similar sedimentary environments. Forward modeling confirms their similar reservoir characteristics, while the reservoir distribution in the 2D seismic survey area is effectively mapped via the inversion. The results show that for a 2D seismic survey area characterized by a low degree of hydrocarbon exploration and appraisal, and a lack of well logging data, the proposed approach can confirm the sedimentary characteristics that correspond to the seismic reflection characteristics, and can quantitatively map the reservoir thickness.
Study on numerical simulation method of viscosity time-varying slurry diffusion law
Authors: Zhang Guohua , Zhang Jiaxing , Pei Xiangjun , He Zhihao , Zheng Guoxun
Published: January 2023

In this study, finite element and finite difference methods were used for numerical calculations. The law of slurry diffusion in the inclined plane cracks is summarized in this study. Further, the equation describing the diffusion of slurry with time-varying viscosity in the plane fracture with dip angle was derived, and the mathematical model of slurry diffusion control equation and improved entropy clustering algorithm were developed. Thus, the law of slurry diffusion with time-varying viscosity in an inclined plane fractured rock mass was studied in detail, and the control equation obtained was modified to improve the prediction accuracy of diffusion of slurry with time-varying viscosity. By applying the model to actual working conditions, the results highlighted that the improved entropy clustering algorithm could more accurately describe the relationship between the factors influencing slurry diffusion and the slurry diffusion radius. The improved entropy clustering algorithm model can adjust the weights of the factors influencing the slurry diffusion in the diffusion control equation, which leads to a more flexible and more accurate slurry diffusion control equation.
Automatic karst cave detection from seismic images via a convolutional neural network and transfer learning
Authors: Huang Jianping , Huang Yunbo , Ma Yangyang , Liu Bowen
Published: January 2023

The identification of karst caves in seismic imaging profiles is a key step for reservoir interpretation, especially for carbonate reservoirs with extensive cavities. In traditional methods, karst caves are usually detected by looking for the string of beadlike reflections (SBRs) in seismic images, which are extremely time-consuming and highly subjective. We propose an end-to-end convolutional neural network (CNN) to automatically and effectively detect karst caves from 2D seismic images. The identification of karst caves is considered as an image recognition problem of labeling a 2D seismic image with ones on caves and zeros elsewhere. The synthetic training data set including the seismic imaging profiles and corresponding labels of karst caves are automatically generated through our self-defined modeling and data augmentation method. Considering the extreme imbalance between the caves (ones) and non-caves (zeros) in the labels, we adopt a class-balanced loss function to maintain good convergence during the training process. The synthetic tests demonstrate the capability and stability of our proposed network, which is capable of detecting the karst caves from the seismic images contaminated with severe random noise. The physical simulation data example also confirms the effectiveness of our method. To overcome the generalization problem of training the neural network with only synthetic data, we introduce the transfer learning strategy and obtain good results on the seismic images of the field data.
Extreme-wind events in China in the past 50 years and their impacts on sandstorm variations
Authors: Jiang Yingsha , Miao Yunfa , Zhao Yongtao , Liu Jingjing , Gao Yanhong
Published: January 2023

Extreme-wind events not only cause disasters by themselves but can also trigger sandstorms, resulting in significant social and economic losses. Since recent years have experienced more frequent and severe extreme weather events, it is worth to explore how extreme-wind events response to recent climate change and how they impact the sandstorm variation. This work established two indices, EW90 and EW95, to identify extreme-wind events based on the relation between extreme-wind intensity and local-source sandstorm. EW90 and EW95 extreme-wind indices are defined as the daily maximum wind speeds greater than the 90th and 95th quantiles of local long-term historical records. The spatial distributions of EW90 and EW95 extreme-wind events are similar, which is higher in arid and semi-arid and coastal regions, and lower in southern China. Seasonally, extreme-wind events mainly occur in April and May for most areas over China, while they are more frequent from July to August for humid regions. During 1971–2020, both the EW90 and EW95 extreme-wind speeds and annual frequencies have significant decreasing trend (p < 0.01), while the daily mean wind speed does not decrease significantly. Extreme-wind events do not have significant abrupt change as well, while a turning positive trend after 2003 is found for mean wind speed. Moreover, sandstorm days are highly correlated with the EW90 and EW95 extreme-wind events, with linear and partial correlation coefficients around 0.95 and 0.5, respectively, while they do not have significant correlations with mean wind speed. Therefore, the significant reduction of sandstorms over northern China in the past 50 years is mainly due to the substantially decreasing extreme-wind events.
Discovery of solid bitumen in the Cambrian reservoirs and its geological implications in the Ordos Basin, China
Authors: Huang Junping , Li Xiangbo , Tan Kaijun , Xiang Nijiao , Zhang Yan
Published: January 2023

This study reports a comprehensive geochemical analysis of several samples of the solid bitumen recently discovered in the Cambrian reservoirs in drillings and outcrops in the Ordos Basin. The results show that the solid bitumen in the reservoir features intergranular pores and micro-fractures, with mineral particle surfaces of dolomite and limestone, and relatively clear and flat boundaries. The D and G peaks in the laser Raman spectrum were prominent. According to distributions of shapes of the D and G peaks and the relevant parameters of the laser Raman spectrum, the vitrinite equivalent reflectance (Roeq) values were from 2.12% to 3.46% in the solid bitumen. This indicates that the solid bitumen in the reservoirs had undergone significant thermal evolution and was mainly composed of pyrobitumen. Moreover, it mainly consisted of four types of atoms, C, O, Ca, and Mg, which confirms the hypothesis of the significant thermal evolution of the samples. In addition, the analysis of the origin of the Cambrian natural gas and the correlation between the solid bitumen and the potential source rocks show that the solid bitumen in the Cambrian reservoirs of the Southern Basin had features similar to those of the Lower Cambrian source rocks, except for the samples from well T59. All evidence suggests that the high-abundance source rocks of the Lower Cambrian have made considerable contributions to the Cambrian natural gas and the solid bitumen in the Cambrian reservoirs of the Southern Basin. The work here provides a new scientific basis for exploring natural gas in the Cambrian reservoirs and deep strata of the Ordos Basin.
Analysis of the wind regime at high spatial-temporal resolution in the itacaiúnas river watershed, eastern amazon
Authors: Tavares Alexandra Lima , Da Silva Renato Oliveira , Do Carmo Alexandre Melo Casseb , Martins Gabriel Caixeta , Nascimento Wilson Da Rocha , Ferreira Douglas Batista Da Silva , Da Silva Marcio Sousa , Costa Carlos Eduardo Aguiar De Souza , Pontes Paulo Rógenes , Tedeschi Renata Gonçalves
Published: January 2023

In the present study, hourly wind direction and speed data from six subregions along the Itacaiúnas River watershed (IRW), Eastern Amazon, are analyzed over a 1-year period. The data are acquired from six hydrometeorological stations located in areas of the IRW with different characteristics of land use and plant cover. Among the stations studied, Serra Leste (mine to pasture transition) stands out, with prevailing winds from the Southeast and the East-Southeast, in addition to higher wind speeds. In contrast, at the Salobo (forest) station, the lowest wind speeds are observed, and this station presents the highest percentage of calm winds (60%) in the series. In the analysis of the daytime (from 6 a.m. to 5 p.m.) and nighttime (from 6 p.m. to 5 a.m.) wind cycles, the breeze and mesoscale circulation system are identified. Predominantly northerly winds are observed acting on the Abadia Farm and IFPA Rural (Federal Institute of Education, Science and Technology of Pará) stations, both during the day and at night, overlapping with the local breeze effects. Daily (24 h) and associated breeze circulation (12 h) cycle frequency signals are identified through wavelet transform analyses of the wind for all stations. The interference from large-scale phenomena, such as the Intertropical Convergence Zone (ITCZ) and the South Atlantic Convergence Zone (SACZ), which operate in the region, is evident. Finally, the data show that the differences in wind patterns are also due to environmental aspects such as plant cover, land use, and topography.
Fracture development and controlling factors at metamorphic buried-hill reservoirs of Bozhong 19-6 gas field in Bohai Bay, East China
Authors: Mi Lijun , Fan Tingen , Fan Hongjun , Niu Tao , Gong Lei , Su Xiaocen , Sun Yonghe , Cheng Yuqi
Published: January 2023

Fractures of multi-scales and multi-origins are primary storage space and effective seepage channels for metamorphic buried-hill reservoirs. They not only allow communication between various pores to enhance storage and seepage capacity, but also are essential for high yields. Fracture development and controlling factors at metamorphic buried-hill reservoirs of Bozhong 19-6 Gas Field were investigated based on imaging log, core data, experiments, e.g., thin sections and scanning electron microscope, and outcrop description. Results show that structural fractures, weathering fractures and dissolution fractures were developed in the metamorphic buried-hill reservoirs in the study area, among which structural fractures and weathering fractures are the most popular ones. However, fracture types varied obviously among different structure positions. Lithology, fault, weathering crust and ancient landform are primary factors affecting fracture distribution. Fractures were prone to be developed at lithology with high bright mineral contents. Faults were characterized by a dual structure including fault core and damage zone. Fracture density followed a decreasing trend with increasing distance from faults. Damage zone could be identified when fracture density was consistent with regional fracture density. The width of the damage zone was determined by factors such as fault scale and structure location. Well-connected weathering fractures were popular at the leached unit, with structural fractures of secondary importance. The unweathered unit was dominated by structural fractures with low density.
Study on the mechanism of coal pillar breaking and fracture development under repeated mining in a close seam group
Authors: Teng Fei , Yu Minggao , Han Xuefeng , Chao Jiangkun
Published: January 2023

The study show the influence of coal mining on pillar under a repeated mining, in a close coal seam group, the fracture and instability process and influence mechanism of fracture development on the oxidation of coal pillars. In this paper, FLAC3D numerical simulation software is used to simulate the dynamic evolution characteristics of stress, displacement of the upper coal pillar. The results show that 1) The theoretical length of the fracture along the strike of the upper coal pillar is obtained by establishing the mechanical model of the upper coal pillar, which is consistent with the numerical simulation results. 3) In this paper, according to the dynamic evolution characteristics of displacement and stress on the coal pillar, the coal pillar is divided into the “step subsidence area”, “fracture compaction area” and “reverse stress area”, and the high risk area of the coal spontaneous combustion is determined.
Fracturing criterion of rock hydrofracturing considering pore pressure effect
Authors: Huang Bingxiang , Li Heng , Zhao Xinglong , Xing Yuekun
Published: January 2023

Traditional hydraulic fracturing theory believes that as the initial pore pressure increases, the breakdown pressure of the rock will decrease. Previous experimental studies have shown that the breakdown pressure of rock hydraulic fracturing may increase with the increase of initial pore pressure (gradient), which cannot be explained by traditional theory. The current understanding of the effect of pore pressure and its gradient during hydraulic fracturing is still unclear. In this study, the pore pressure effect of rock hydraulic fracturing is analyzed based on a large number of macroscopic and microscopic phenomena of rock hydraulic fracturing in the previous study. Then, a new fracture criterion of rock fracturing is built considering the pressure-gradient effect. This new fracture criterion can reflect the main influence factors, including the rock particle size, porosity, pumping flow, inner diameter of open hole section, length of main fracture, height of main fracture (or length of open hole section), fluid viscosity, pore pressure, minimum initial in situ stress and rock tensile strength. The new fracture criterion is examined by the rock fracturing experiment which considering the pressure-gradient effect. The results show that the proposed fracture criterion considering the pore pressure effect can well predict the breakdown pressure of rock, and the prediction trend is consistent with the experimental results. The average error is less than 1% when adopting the present fracture criterion. The parameter sensitivity of the fracture criterion is analyzed. Results show that the fracture pressure increases with the rock porosity and this trend becomes more apparent with a larger initial pore pressure. It shows that the fracture pressure increases with the pumped flow rate. Besides, it shows that the fracture pressure decreases when increasing the particle size of the rock, but the decreasing trend gradually slows down. The research results can provide a theoretical basis for the mechanism of rock hydraulic fracturing and the structural modification effect of fluids in rock engineering.
Keeping distance with a telepresence robot: A pilot study
Authors: Leoste Janika , Heidmets Mati , Virkus Sirje , Talisainen Aleksei , Rebane Martin , Kasuk Tiina , Tammemäe Kalle , Kangur Katrin , Kikkas Kaido , Marmor Kristel
Published: January 2023

Introduction

Telepresence robots (TPRs) are the subject of an emerging field of application and research that has recently received attention from various disciplines. Most of the relevant research has been done in computer science, while the interest from psychology and education has been relatively modest. Proximity plays an important role in personal interactions. Although human spatial behavior has been widely studied in social psychology, little attention has been paid to the spatial behavior of humans and TPRs.

Methods

The purpose of this paper is to present the results of a pilot study that investigated a certain aspect of spatial behavior – physical proximity or interpersonal distance – based on four social zones of interpersonal distance that characterize Western culture: intimate, personal, social, and public. The study conducted an experiment involving participants both in person and via TPRs, using the Double 3 TPRs in various simulated situations.

Results

According to the findings, when interacting with a TPR, most participants maintained a communication distance of 60 to 160 cm, which is the borderline between personal and social distance, quite similar to normal human-to-human social communication. Status and previous relationship did not play any role in the choice of communication distance, but there were significant gender differences. On average, male participants chose a shorter distance to interact with TPRs compared to female participants. Persons with previous computer gaming experience chose a significantly shorter communication distance compared to persons with no such experience. A little more than half of the participants found the method of communication through TPRs to be pleasant.

Discussion

TPR mediated persons might be perceived as “real” when communicating with physically present persons, with similar norms applied as in human-to-human social interactions. Especially in the context of classroom communication, people keep communication distances comparable to far personal or close social distances. These findings suggest that implementation of TPRs in education does not put additional requirements for physical space in classroom.
A novel fault diagnosis method for power grid based on graph Fourier transform
Authors: Liao Xiaojun , Yu Senlin , Zhang Li , Feng Xianzheng , Wang Xiaoru
Published: January 2023

The fast and robust identification of fault elements is essential for the security and continuous operation of the power grid. The existing methods might be maloperation for bad data disturbance and require strict and exact synchronization. To address the challenge, this paper uses the conflict graph to propose a new sensitivity graph signal model for the power grid fault diagnosis. Next, a novel graph Fourier transform (GFT)-based method is proposed to diagnose the fault branch. Firstly, the measurement sensitivity graph signals are constructed by the conflict graph model, where the data is from activated recorders and protection devices. Next, the eigenvalue and GFT coefficient are used to extract the frequency characteristics of the signals. The fault branches provide the maximum contribution rate to the high-frequency coefficient of GFT. Then, for each node, the importance degree of the measurement sensitivity conflict graph signal is defined. The high-frequency importance degree-based method is proposed to discriminate the fault branch. Finally, simulations and practical cases verify the correctness and effectiveness of the proposed method. The proposed method owns fast faults diagnosis and good practicability. Additionally, the identification accuracy is high and the method is robust to bad data interference, due to considering measured data from whole activated fault recorders and protection devices.
China’s green finance and total factor energy efficiency
Authors: Zhou Chaobo , Shaozhou Qi , Yuankun Li
Published: January 2023

Based on data on 280 prefecture-level cities from 2008 to 2019, this study uses a difference-in-difference (DID) model to first analyze the impact of China’s green finance pilot policy (GFPP) on total factor energy efficiency (TFEE) and then further investigate the mediating and heterogeneous effects of GFPP. Results indicate that first, GFPP effectively improves TFEE, and the robustness tests show that the estimation results are reliable. Second, GFPP mainly improves TFEE by promoting industrial structure optimization and green technology innovation. Last, the role of GFPP in improving TFEE is mainly reflected in cities with high environmental protection enforcement and intellectual property protection. Therefore, China must expand the GFPP scope, further improve the local green finance practice capability, actively guide green fund to support energy technology innovation, accelerate green industrial transformation, and pool social forces to jointly promote green economic development.