bluuebunny/crossref_metadata_2025 huggingface dataset:
Switching Patients from Originator to Biosimilar Medications in Rheumatoid Arthritis: Limiting The ‘Nocebo’ Effect
Authors: Ali Rugina , Ford Phil
Published: January 2023

Biosimilars have been available in Europe since 2006, and biosimilars of monoclonal antibodies since 2013, and are now a widespread clinical reality. Since their introduction, various sources of data have become available to help physicians make knowledgeable decisions about their use. For example, randomised clinical trials can demonstrate the comparable efficacy and safety between the biosimilar and its reference biologic. Real-world evidence from registries and individual clinical centres provide additional data on the actual use of biosimilars across different therapeutic indications and broader patient populations, including those who have switched from the reference biologic to the biosimilar, while offering additional understanding of the long-term safety and effectiveness. Well-informed decisions based on a solid understanding of these data are important and can help the physician guide the patient to their own well-informed decision, thereby reducing the possibility of a nocebo effect. Here we review available data sources and look at best practice examples of communicating with patients.
Photoacoustic signal enhancement in dual-contrast gastrin-releasing peptide receptor-targeted nanobubbles
Authors: Zhao Shensheng , Lee Leanne , Zhao Yang , Liang Nu-Chu , Chen Yun-Sheng
Published: January 2023

Translatable imaging agents are a crucial element of successful molecular imaging. Photoacoustic molecular imaging relies on optical absorbing materials to generate a sufficient signal. However, few materials approved for human use can generate adequate photoacoustic responses. Here we report a new nanoengineering approach to further improve photoacoustic response from biocompatible materials. Our study shows that when optical absorbers are incorporated into the shell of a gaseous nanobubble, their photoacoustic signal can be significantly enhanced compared to the original form. As an example, we constructed nanobubbles using biocompatible indocyanine green (ICG) and biodegradable poly(lactic-co-glycolic acid) (PLGA). We demonstrated that these ICG nanobubbles generate a strong ultrasound signal and almost four-fold photoacoustic signal compared to the same concentration of ICG solution; our theoretical calculations corroborate this effect and elucidate the origin of the photoacoustic enhancement. To demonstrate their molecular imaging performance, we conjugated gastrin-releasing peptide receptor (GRPR) targeting ligands with the ICG nanobubbles. Our dual photoacoustic/ultrasound molecular imaging shows a more than three-fold enhancement in targeting specificity of the GRPR-targeted ICG nanobubbles, compared to untargeted nanobubbles or prostate cancer cells not expressing GRPR, in a prostate cancer xenograft mouse model in vivo.
A local-saturation-and-delay MRI method for evaluation of red blood cells aggregation in vivo for tumor-bearing or drug-used rats
Authors: Shan Haiwei , Shi Lei , Liu Shuang , Yuan Yaping , Li Hongchuang , Chen Shizhen , Zhou Xin
Published: January 2023

Hyperviscosity syndrome (HVS) is a combination of clinical signs and symptoms related to increased blood viscosity. HVS can increase the thrombotic risk by causing a major disturbance to the blood flow, which is usually found in the advanced stages of the tumor. Moreover, some of the drugs used in chemotherapy, such as 5-fluorouracil and erythropoietin, are also capable of causing HVS through their respective pathways. Clinically, the viscosity of a patient’s blood sample is measured by a rotary rheometer to estimate the risk of hyperviscosity syndrome. However, the measurement of blood viscosity in vitro is easily affected by storage time, storage environment, and anticoagulants. In addition, the fluid conditions in the rheometer are quite different from those in natural blood vessels, making this method inappropriate for evaluating blood viscosity and its effects in vivo under physiological condition. Herein, we presented a novel magnetic resonance imaging method called local-saturation-and-delay imaging (LSDI). The radial distributions of flow velocity measured by LSDI are consistent with the Ultrasonic (US) method (Spearman correlation coefficient r = 0.990). But the result of LSDI is more stable than US (p < 0.0001). With the LSDI method, we can directly measure the radial distribution of diastolic flow velocity, and further use these data to calculate the whole blood relative viscosity (WBRV) and erythrocyte aggregation trend. It was a strong correlation between the results measured by LSDI and rotary rheometer in the group of rats given erythropoietin. Furthermore, experimental results in glioma rats indicate that LSDI is equivalent to a rheometer as a method for predicting the risk of hyperviscosity syndrome. Therefore, LSDI, as a non-invasive method, can effectively follow the changes in WBRV in rats and avoid the effect of blood sampling during the experiment on the results. In conclusion, LSDI is expected to become a novel method for real-time in vivo recognition of the cancer progression and the influence of drugs on blood viscosity and RBC aggregation.
A preliminary biomechanical study on trachea reconstruction surgery using the clavicular periosteum
Authors: Zhu Xiaoli , Sun Kangli , Xia Xin , Chen Yu , Sun Anqiang , Chen Xingming
Published: January 2023

Introduction: The clavicular periosteum is a suitable material for trachea reconstruction. However, because the periosteum is softer and has different mechanical properties than tracheal cartilage, the mechanical loads under physiological conditions after trachea reconstruction may cause collapse or stenosis of the repaired trachea.

Methods: In this study, the mechanical properties of the clavicular periosteum were tested, and the 3D trachea geometry was constructed based on CT-scanning images acquired before the surgery. Differing degrees of stenosis (0%, 33%, and 55%) for the repaired trachea sections were predetermined, presenting the different degrees of the tracheal cross-sectional area immediately after clavicular periosteum reconstruction. Then the biomechanical environments of the trachea and the airflow were simulated and analyzed.

Results: In the fluid mechanics simulation, the air pressure on the patch area decreased with increasing degrees of stenosis, while the fluid velocity increased as stenosis increased. In solid mechanics simulations, patch area deformation increased as the cross-sectional area of the trachea decreased, and the stress in the patch increased as stenosis increased.

Discussion: The solid stress changes may cause tissue remodeling, thickening, and scarring of the patch area. The fluid mechanical changes in the repaired trachea would further aggravate the stenosis. The numerical simulation study would provide references for biomechanical evaluation of trachea reconstruction surgery. The surgical indications may be expanded in the future based on the model prediction results.
Mutational analysis of the spike protein of SARS-COV-2 isolates revealed atomistic features responsible for higher binding and infectivity
Authors: Hanifa Muhammad , Salman Muhammad , Fatima Muqaddas , Mukhtar Naila , Almajhdi Fahad N. , Zaman Nasib , Suleman Muhammad , Ali Syed Shujait , Waheed Yasir , Khan Abbas
Published: January 2023

Introduction: The perpetual appearance of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-COV-2), and its new variants devastated the public health and social fabric around the world. Understanding the genomic patterns and connecting them to phenotypic attributes is of great interest to devise a treatment strategy to control this pandemic.

Materials and Methods: In this regard, computational methods to understand the evolution, dynamics and mutational spectrum of SARS-CoV-2 and its new variants are significantly important. Thus, herein, we used computational methods to screen the genomes of SARS-CoV-2 isolated from Pakistan and connect them to the phenotypic attributes of spike protein; we used stability-function correlation methods, protein-protein docking, and molecular dynamics simulation.

Results: Using the Global initiative on sharing all influenza data (GISAID) a total of 21 unique mutations were identified, among which five were reported as stabilizing while 16 were destabilizing revealed through mCSM, DynaMut 2.0, and I-Mutant servers. Protein-protein docking with Angiotensin-converting enzyme 2 (ACE2) and monoclonal antibody (4A8) revealed that mutation G446V in the receptor-binding domain; R102S and G181V in the N-terminal domain (NTD) significantly affected the binding and thus increased the infectivity. The interaction pattern also revealed significant variations in the hydrogen bonding, salt bridges and non-bonded contact networks. The structural-dynamic features of these mutations revealed the global dynamic trend and the finding energy calculation further established that the G446V mutation increases the binding affinity towards ACE2 while R102S and G181V help in evading the host immune response. The other mutations reported supplement these processes indirectly. The binding free energy results revealed that wild type-RBD has a TBE of −60.55 kcal/mol while G446V-RBD reported a TBE of −73.49 kcal/mol. On the other hand, wild type-NTD reported −67.77 kcal/mol of TBE, R102S-NTD reported −51.25 kcal/mol of TBE while G181V-NTD reported a TBE of −63.68 kcal/mol.

Conclusions: In conclusion, the current findings revealed basis for higher infectivity and immune evasion associated with the aforementioned mutations and structure-based drug discovery against such variants.
Steps of actin filament branch formation by Arp2/3 complex investigated with coarse-grained molecular dynamics
Authors: Zhang Shuting , Vavylonis Dimitrios
Published: January 2023

The nucleation of actin filament branches by the Arp2/3 complex involves activation through nucleation promotion factors (NPFs), recruitment of actin monomers, and binding of the complex to the side of actin filaments. Because of the large system size and processes that involve flexible regions and diffuse components, simulations of branch formation using all-atom molecular dynamics are challenging. We applied a coarse-grained model that retains amino-acid level information and allows molecular dynamics simulations in implicit solvent, with globular domains represented as rigid bodies and flexible regions allowed to fluctuate. We used recent electron microscopy structures of the inactive Arp2/3 complex bound to NPF domains and to mother actin filament for the activated Arp2/3 complex. We studied interactions of Arp2/3 complex with the activating VCA domain of the NPF Wiskott-Aldrich syndrome protein, actin monomers, and actin filament. We found stable configurations with one or two actin monomers bound along the branch filament direction and with CA domain of VCA associated to the strong and weak binding sites of the Arp2/3 complex, supporting prior structural studies and validating our approach. We reproduced delivery of actin monomers and CA to the Arp2/3 complex under different conditions, providing insight into mechanisms proposed in previous studies. Simulations of active Arp2/3 complex bound to a mother actin filament indicate the contribution of each subunit to the binding. Addition of the C-terminal tail of Arp2/3 complex subunit ArpC2, which is missing in the cryo-EM structure, increased binding affinity, indicating a possible stabilizing role of this tail.
Prospects for utilizing microbial consortia for lignin conversion
Authors: Rodriguez Alberto , Hirakawa Matthew P. , Geiselman Gina M. , Tran-Gyamfi Mary B. , Light Yooli K. , George Anthe , Sale Kenneth L.
Published: January 2023

Naturally occurring microbial communities are able to decompose lignocellulosic biomass through the concerted production of a myriad of enzymes that degrade its polymeric components and assimilate the resulting breakdown compounds by members of the community. This process includes the conversion of lignin, the most recalcitrant component of lignocellulosic biomass and historically the most difficult to valorize in the context of a biorefinery. Although several fundamental questions on microbial conversion of lignin remain unanswered, it is known that some fungi and bacteria produce enzymes to break, internalize, and assimilate lignin-derived molecules. The interest in developing efficient biological lignin conversion approaches has led to a better understanding of the types of enzymes and organisms that can act on different types of lignin structures, the depolymerized compounds that can be released, and the products that can be generated through microbial biosynthetic pathways. It has become clear that the discovery and implementation of native or engineered microbial consortia could be a powerful tool to facilitate conversion and valorization of this underutilized polymer. Here we review recent approaches that employ isolated or synthetic microbial communities for lignin conversion to bioproducts, including the development of methods for tracking and predicting the behavior of these consortia, the most significant challenges that have been identified, and the possibilities that remain to be explored in this field.
Influence of ionic conditions on knotting in a coarse-grained model for DNA
Authors: Wettermann Sarah , Datta Ranajay , Virnau Peter
Published: January 2023

We investigate knotting probabilities of long double-stranded DNA strands in a coarse-grained Kratky-Porod model for DNA with Monte Carlo simulations. Various ionic conditions are implemented by adjusting the effective diameter of monomers. We find that the occurrence of knots in DNA can be reinforced considerably by high salt conditions and confinement between plates. Likewise, knots can almost be dissolved completely in a low salt scenario. Comparisons with recent experiments confirm that the coarse-grained model is able to capture and quantitatively predict topological features of DNA and can be used for guiding future experiments on DNA knots.
From design to clinic: Engineered peptide nanomaterials for cancer immunotherapy
Authors: Du Jing-Jing , Su Zhenhong , Yu Haoyi , Qin Sanhai , Wang Dongyuan
Published: January 2023

Immunotherapy has revolutionized the field of cancer therapy. Nanomaterials can further improve the efficacy and safety of immunotherapy because of their tunability and multifunctionality. Owing to their natural biocompatibility, diverse designs, and dynamic self-assembly, peptide-based nanomaterials hold great potential as immunotherapeutic agents for many malignant cancers, with good immune response and safety. Over the past several decades, peptides have been developed as tumor antigens, effective antigen delivery carriers, and self-assembling adjuvants for cancer immunotherapy. In this review, we give a brief introduction to the use of peptide-based nanomaterials for cancer immunotherapy as antigens, carriers, and adjuvants, and to their current clinical applications. Overall, this review can facilitate further understanding of peptide-based nanomaterials for cancer immunotherapy and may pave the way for designing safe and efficient methods for future vaccines or immunotherapies.
Lethal activity of BRD4 PROTAC degrader QCA570 against bladder cancer cells
Authors: Wang Qiang , Li Baohu , Zhang Wenkai , Li Zhuoyue , Jiang Bo , Hou Sichuan , Ma Shumin , Qin Chong
Published: January 2023

Bladder cancer is the most common malignancy of the urinary system. Efforts to identify innovative and effective therapies for bladder cancer are urgently needed. Recent studies have identified the BRD4 protein as the critical factor in regulation of cell proliferation and apoptosis in bladder cancer, and it shows promising potential for pharmacologic treatment against bladder cancer. In this study, we have evaluated the biological function of QCA570, a novel BET degrader, on multiple bladder cancer cells and explore its underlying mechanisms. QCA570 potently induces degradation of BRD4 protein at nanomolar concentrations, with a DC50 of ∼ 1 nM. It decreases EZH2 and c-MYC levels by transcriptional suppression and protein degradation. Moreover, the degrader significantly induces cell apoptosis and cycle arrest and shows antiproliferation activity against bladder cancer cells. These findings support the potential efficacy of QCA570 on bladder cancer.
Pro-inflammatory role of Wnt/β-catenin signaling in endothelial dysfunction
Authors: Wadey Kerry S. , Somos Alexandros , Leyden Genevieve , Blythe Hazel , Chan Jeremy , Hutchinson Lawrence , Poole Alastair , Frankow Aleksandra , Johnson Jason L. , George Sarah J.
Published: January 2023

Background

Endothelial dysfunction is a critical component of both atherosclerotic plaque formation and saphenous vein graft failure. Crosstalk between the pro-inflammatory TNF-α-NFκB signaling axis and the canonical Wnt/β-catenin signaling pathway potentially plays an important role in regulating endothelial dysfunction, though the exact nature of this is not defined.

Results

In this study, cultured endothelial cells were challenged with TNF-α and the potential of a Wnt/β-catenin signaling inhibitor, iCRT-14, in reversing the adverse effects of TNF-α on endothelial physiology was evaluated. Treatment with iCRT-14 lowered nuclear and total NFκB protein levels, as well as expression of NFκB target genes, IL-8 and MCP-1. Inhibition of β-catenin activity with iCRT-14 suppressed TNF-α-induced monocyte adhesion and decreased VCAM-1 protein levels. Treatment with iCRT-14 also restored endothelial barrier function and increased levels of ZO-1 and focal adhesion-associated phospho-paxillin (Tyr118). Interestingly, inhibition of β-catenin with iCRT-14 enhanced platelet adhesion in cultured TNF-α-stimulated endothelial cells and in an ex vivo human saphenous vein model, most likely via elevating levels of membrane-tethered vWF. Wound healing was moderately retarded by iCRT-14; hence, inhibition of Wnt/β-catenin signaling may interfere with re-endothelialisation in grafted saphenous vein conduits.

Conclusion

Inhibition of the Wnt/β-catenin signaling pathway with iCRT-14 significantly recovered normal endothelial function by decreasing inflammatory cytokine production, monocyte adhesion and endothelial permeability. However, treatment of cultured endothelial cells with iCRT-14 also exerted a pro-coagulatory and moderate anti-wound healing effect: these factors may affect the suitability of Wnt/β-catenin inhibition as a therapy for atherosclerosis and vein graft failure.
Comprehensive analysis of transcriptomics and metabolomics to understand tail-suspension-induced myocardial injury in rat
Authors: Liu Yu , Guo Liguo , Xu Chong , Liu Junlian , Fan Quanchun , Gai Yuqing , Zhao Shuang , Wu Xiaorui , Mi Tao , Wang Jiaping , Li Yongzhi
Published: January 2023

Background/Aims

The effect and underlying mechanism of microgravity on myocardium still poorly understood. The present study aims to reveal the effect and underlying mechanism of tail-suspension-induced microgravity on myocardium of rats.

Methods

Tail-suspension was conducted to simulate microgravity in rats. Echocardiography assay was used to detect cardiac function. The cardiac weight index was measured. Hematoxylin and eosin (HE) staining and transmission electron microscopy assay were conducted to observe the structure of the tissues. RNA sequencing and non-targeted metabolomics was employed to obtain transcriptome and metabolic signatures of heart from tail-suspension-induced microgravity and control rats.

Results

Microgravity induced myocardial atrophy and decreased cardiac function in rats. Structure and ultrastructure changes were observed in myocardium of rats stimulated with microgravity. RNA sequencing for protein coding genes was performed and identified a total of 605 genes were differentially expressed in myocardium of rats with tail suspension, with 250 upregulated and 355 downregulated (P < 0.05 and | log2fold change| > 1). A total of 55 differentially expressed metabolites were identified between the two groups (VIP > 1 and P < 0.05) by the metabolic profiles of heart tissues from microgravity groups and control. Several major pathways altered aberrantly at both transcriptional and metabolic levels, including FoxO signaling pathway, Amyotrophic lateral sclerosis, Histidine metabolism, Arginine and proline metabolism.

Conclusion

Microgravity can induce myocardial atrophy and decreases cardiac function in rats and the molecular alterations at the metabolic and transcriptomic levels was observed, which indicated major altered pathways in rats with tail suspension. The differentially expressed genes and metabolites-involved in the pathways maybe potential biomarkers for microgravity-induced myocardial atrophy.
Comparing the pooled cohort equations and coronary artery calcium scores in a symptomatic mixed Asian cohort
Authors: Baskaran Lohendran , Lee Jing Kai , Ko Michelle Shi Min , Al’Aref Subhi J. , Neo Yu Pei , Ho Jien Sze , Huang Weiting , Yoon Yeonyee Elizabeth , Han Donghee , Nakanishi Rine , Tan Swee Yaw , Al-Mallah Mouaz , Budoff Matthew J. , Shaw Leslee J.
Published: January 2023

Background

The value of pooled cohort equations (PCE) as a predictor of major adverse cardiovascular events (MACE) is poorly established among symptomatic patients. Coronary artery calcium (CAC) assessment further improves risk prediction, but non-Western studies are lacking. This study aims to compare PCE and CAC scores within a symptomatic mixed Asian cohort, and to evaluate the incremental value of CAC in predicting MACE, as well as in subgroups based on statin use.

Methods

Consecutive patients with stable chest pain who underwent cardiac computed tomography were recruited. Logistic regression was performed to determine the association between risk factors and MACE. Cohort and statin-use subgroup comparisons were done for PCE against Agatston score in predicting MACE.

Results

Of 501 patients included, mean (SD) age was 53.7 (10.8) years, mean follow-up period was 4.64 (0.66) years, 43.5% were female, 48.3% used statins, and 50.0% had no CAC. MI occurred in 8 subjects while 9 subjects underwent revascularization. In the general cohort, age, presence of CAC, and ln(Volume) (OR = 1.05, 7.95, and 1.44, respectively) as well as age and PCE score for the CAC = 0 subgroup (OR = 1.16 and 2.24, respectively), were significantly associated with MACE. None of the risk factors were significantly associated with MACE in the CAC > 0 subgroup. Overall, the PCE, Agatston, and their combination obtained an area under the receiver operating characteristic curve (AUC) of 0.501, 0.662, and 0.661, respectively. Separately, the AUC of PCE, Agatston, and their combination for statin non-users were 0.679, 0.753, and 0.734, while that for statin-users were 0.585, 0.615, and 0.631, respectively. Only the performance of PCE alone was statistically significant (p = 0.025) when compared between statin-users (0.507) and non-users (0.783).

Conclusion

In a symptomatic mixed Asian cohort, age, presence of CAC, and ln(Volume) were independently associated with MACE for the overall subgroup, age and PCE score for the CAC = 0 subgroup, and no risk factor for the CAC > 0 subgroup. Whilst the PCE performance deteriorated in statin versus non-statin users, the Agatston score performed consistently in both groups.
An optimized three-dimensional time-space domain staggered-grid finite-difference method
Authors: Liu Wei , Wang Wei , You Jiachun , Cao Junxing , Wang Haibo
Published: January 2023

Numerical simulation of three-dimensional (3D) seismic wavefields forms the basis of the research on the migration methods of 3D seismic data based on wave equations. Because the simulation precision of wavefield extrapolation determines the imaging accuracy to a certain extent, it is very important to study how to enhance the forward modeling precision of 3D seismic wavefields. Thus, we build on an optimized 3D staggered-grid finite-difference (SFD) method with high simulation precision based on two-dimensional (2D) seismic modeling. Since it generates the corresponding difference coefficients by utilizing the least square (LS) method to minimize the objective function constructed by the time-space domain dispersion relation of the 3D acoustic wave equation, our optimized time-space domain LS-based 3D SFD method can effectively enhance the modeling precision of the 3D seismic wavefields in theory compared with the 3D SFD methods based on the Taylor-series expansion (TE), especially for the large wavenumber range. Examining the numerical dispersion, algorithm stability and computational cost, we compare our optimized time-space domain LS-based 3D SFD method with three conventional TE-based and LS-based 3D SFD methods to illustrate and demonstrate its effectiveness and feasibility. The numerical examples from different 3D models suggest that our optimized time-space domain LS-based 3D SFD method can generate less numerical dispersion and higher simulation accuracy for 3D seismic wavefields than three other conventional 3D SFD methods, but its stability condition is stricter and its computational cost is slightly higher.
Analytical solution for the influence of irregular shape loads on near borehole strain observations
Authors: Yan Wei , Li Zirui
Published: January 2023

Borehole strain observations are widely used to research slow earthquakes, volcanic activity and seismic precursors. Due to the high resolution and sensitivity, borehole strain monitoring records not only tectonic signals, but also signals from environmental disturbances. Based on the analytical solution of the displacement caused by the punctate load model, this paper derives the equation of the peripheral strain field, which provides a theoretical basis for the quantitative calculation of the load effect of borehole strain observation, and proposes a method for calculating the strain effect of two-dimensional and three-dimensional irregularly shaped loads. The results show that, 1) For the two-dimensional irregular shape load model, we can calculate it by vector superposition after load scattering. 2) For the three-dimensional irregular shape load model, we can calculate by assigning different weights to the scattering points after load scattering using two-dimensional irregular shape load method. The convergence process during the vector superposition shows the correctness and feasibility of the method, and the study can provide a research basis for the quantitative analysis of the influence of peripheral load disturbance in borehole strain observation.
Reservoir properties and hydrocarbon enrichment law of Chang 1 oil layer group in Yanchang Formation, Wanhua area, Ordos Basin
Authors: Ji Chaohui , Xue Chengwei , Sun Min , Li Xiang , Wang Li
Published: January 2023

Evaluation of tight oil reservoir properties is of great significance to the exploration of oil and gas in tight reservoirs. The Chang 1 Member of the Yanchang Formation in the Wanhua Area, Ordos Basin is a new exploration stratum for tight sandstone oil. The lack of understanding of reservoir characteristics and crude oil enrichment rules has seriously restricted the efficient development of oil and gas resources in this stratum. In this study, the reservoir characteristics of the Chang 1 Member in the Wanhua area and the effects of superimposed sand bodies, structures and paleogeomorphology on accumulation of hydrocarbons were systematically studied. The Chang 1 sandstone is a typical ultra-low porosity-ultra-low permeability reservoir, and it has experienced destructive diagenesis of mechanical compaction, pressure solution and cementation, and constructive diagenesis of dissolution. Strong pressure solution caused the secondary enlargement of quartz and feldspar and the formation of patchy dense mosaic structures. The target layer has experienced argillaceous, siliceous and carbonate cementations. Moreover, the sandstone reservoir in the Chang 1 Member also experienced strong dissolution, and it is the main factor for the formation of secondary pores and the improvement of reservoir physical properties. The study also found that the main types of pores in the Chang 1 Member are intergranular dissolved pores and remaining intergranular pores. Superimposed sand bodies, nose-shaped uplifts, dominant facies and eroded paleo-highlands have significant effects on the hydrocarbon accumulation. Based on this study, it was found that the migration and accumulation mode of hydrocarbons in the Chang 1 reservoir belongs to the ladder-like climbing migration + structural ridge accumulation type. In addition, sand body thickness is an important controlling factor for the hydrocarbon accumulation. At present, the discovered crude oil in the Chang 1 Member is always distributed in the areas with thick sand bodies (>20 m), and most of the sand bodies have a thickness in the range of 25–40 m, and the effective thickness is in the range of 2–6 m. In addition, the eroded highlands are the highest topographic units, they are favorable areas for the large-scale accumulation of oil and gas.
Study on coal seam physical characteristics and influence on stimulation: A case study of coal seams in zhengzhuang block
Authors: Lu Yanjun , Han Jinxuan , Zhang Hua , Xu Zhenping , Yang Zhaozhong , Yang Manping , Guo Junfeng , Zhu Hongjian , Qi Yu
Published: January 2023

Coalbed Methane (CBM) is an unconventional form of natural gas which is self-generated and self-stored in coal seams. In order to realize the effective exploitation of CBM in Zhengzhuang block, microstructure, wettability, permeability, rock mechanics and in-situ stress of coal were studied in this research. It is found that high rank anthracite characterized by high vitrinite content and low inorganic mineral content, is abundant in CBM. More than 96% of inorganic minerals are clays dominated by kaolinite and illite. Various types of pores are developed on the coal. The wettability of coal differs from high to low to surface water, active water, and foam fracturing fluid; and contact angles of coal with active water and foam fracturing fluid decrease with the increase of burial depth. Gradients of fracture pressure and closure pressure in No.3 coal seam are higher than that of No.15 coal seam. The elastic modulus of coal is lower than that of sandstone. The construction curve of hydraulic fracturing shows that, when the construction flow rate and sand quantity are similar, the construction pressure of prepad in No.3 coal seam is lower than the pumping pressure of No.15 coal seam, but the propagated pressure is higher than that of No.15 coal seam. The drainage effect of No.3 coal seam with large pore volume, shallow burial depth and obvious fracture pressure is better than that of No.15 coal seam. The comprehensive understanding of coal physical properties and engineering practice in the block provide certain guiding significance to the CBM exploitation in Qinshui Basin.
Application of a model-driven simultaneous prestack inversion of rock physical properties in ultra-deep Ordovician carbonate reservoirs in the Shunbei area
Authors: Wang Zhiwei , Fu Li-Yun , Jian Shikai , Deng Wubing
Published: January 2023

Synchronous prestack inversion technology has been widely used to predict the fluid and lithological properties of reservoirs. Its prediction accuracy depends on the seismic data quality. Ultra-deep carbonate reservoirs in the Shunbei area of the Tarim Basin were used as research objects. Based on the shear wave (S-wave) prediction method, petrophysical logging analysis was carried out to select the physical property-sensitive elastic parameters. A physical property indicator with porosity as the target curve was constructed to quantitatively characterize the differences in physical properties in this area. The signal-to-noise ratio (SNR) and resolution of the dataset were improved by preprocessing the seismic and logging data. P- and S-wave impedances and densities obtained from prestack synchronous inversion, which integrate the physical property indicator model. Spatial distribution and transverse variation of the physical parameters of the Ordovician carbonate reservoirs are described. The planar distribution of reservoirs can be effectively predicted.
Digital construction of geophysical well logging curves using the LSTM deep-learning network
Authors: Li Jing , Gao Guozhong
Published: January 2023

A complete well logging suite is needed frequently, but it is either unavailable or has missing parts. The mudstone section is prone to wellbore collapse, which often causes distortion in well logs. In many cases, well logging curves are never measured, yet are needed for petrophysical or other analyses. Re-logging is expensive and difficult to achieve, while manual construction of the missing well logging curves is costly and low in accuracy. The rapid technical evolution of deep-learning algorithms makes it possible to realize the digital construction of missing well logging curves with high precision in an automated fashion. In this article, a workflow is proposed for the digital construction of well logging curves based on the long short-term memory (LSTM) network. The LSTM network is chosen because it has the advantage of avoiding the vanishing gradient problem that exists in traditional recurrent neural networks (RNNs). Additionally, it can process sequential data. When it is used in the construction of missing well logging curves, it not only considers the relationship between each logging curve but also the influence of the data from a previous depth on data at the following depth. This influence is validated by exercises constructing acoustic, neutron porosity, and resistivity logging curves using the LSTM network, which effectively achieves high-precision construction of these missing curves. These exercises show that the LSTM network is highly superior to the RNN in the digital construction of well logging curves, in terms of accuracy, efficiency, and reliability.
The characteristics and genetic mechanisms of the Upper Permian Shangwuerhe clastic reservoir in the eastern Junggar Basin, Northwest China
Authors: Qin Zhijun , Tang Yong , Chang Qiusheng , Liu Chaowei , Ren Haijiao
Published: January 2023

In this paper, the lithology, pore type, throat structure, and physical characteristics of the sandstone and conglomerate reservoirs of the Upper Permian Shangwuerhe Formation in the Fukang Sag of the Junggar Basin were analyzed through rock cast thin section, scanning electron microscopy, fluid inclusions, piezometric mercury, and porosity–permeability analysis. In addition, the reservoir densification mechanism and the genesis of deep effective reservoirs were discussed. The results show that the reservoir is dominated by lithic sandstone (or lithic sandstone conglomerate). The lithic fragments primarily comprise tuffaceous volcanic rocks, supported by grains and cemented by clay, carbonate, authigenic quartz, and laumontite. The reservoir properties are characterized by extra-low porosity and permeability, and the pore type is dominated by inter- and intragrain dissolved pores of lithic fragments, feldspar, and quartz. The pore connectivity is poor due to poorly sorted extra-fine throat channels. The tightness of the reservoir.is due to the strong cementation of calcite, chlorite, montmorillonite, illite-montmorillonite mixed layer, authigenic quartz, and laumontite. Furthermore, the large amount of Ca2+ released by the hydration of tuff rock debris and intermediate–basic volcanic rock debris and the CO2-rich thermal fluid from the deep layers cause the development of several calcites. The formation of several montmorillonites is mainly related to the alteration of filled volcanic ash, and the hydration of volcanic tuff material primarily causes the development of laumontite cementation. The dissolution of feldspar and various volcanic lithic fragments by acidic fluids triggers the physical improvement of the reservoir in the local section.
Development or absence of conjugate fractures in low-permeability sandstones
Authors: Yang Haimeng , Yu Jifeng , Chen Peng , Hu Caifu , Dai Peng
Published: January 2023

Natural fractures are ubiquitous in rocks. The Coulomb law of Mohr’s failure theory predicts that the angle between conjugate failure surfaces is a constant. In the Ordos Basin, observing the development of two groups of conjugate fractures in the field, cores and imaging logging is very difficult. In this paper, the directions of paleocurrents in the Upper Triassic Yanchang Formation of the Ordos Basin are determined by measuring the orientations of field bedding. Through the correlation analysis of paleocurrent and natural fracture orientations, when the sediment comes from a single source, a group of fractures with a large angle between conjugate fractures and the paleocurrent direction is found not to develop. When the sediments in the study area have two provenances, both provenance directions affect the development of conjugate fractures. In the southern Ordos Basin, influenced by the direction of paleocurrent flow in the near-north direction, fractures in the near N‒S direction develop. Through rock mechanics experiments in different directions, the planar anisotropy in rock mechanics parameters caused by the direction of paleocurrent flow is found to be the geological factor leading to various degrees of fracture development in different directions within the Ordos Basin.
Eco-development of oil and gas industry: CCUS-EOR technology
Authors: Yan Liangzhu , Hu Jiajia , Fang Qiongyao , Xia Xueqing , Lei Banyu , Deng Qiao
Published: January 2023

The current status and development prospects of CCUS-EOR technology development are sorted out from the perspective of ecological development. A good foundation is laid to promote the world low-carbon development pattern and the development of CCUS-EOR technology in oil-rich, low-permeability reservoirs. By analyzing the differences between China and the United States regarding the technology level, application scale, and production effect, the development gaps between different countries in terms of CO2 burial for enhanced oil and gas recovery are derived. In response to these gaps, recommendations for responsive technology research and supporting infrastructure construction are proposed, which are of reference significance for advancing the development of large-scale CCUS technology for all of humanity.
Transformation of animal utilization strategies from the late Neolithic to the Han Dynasty in the Hexi Corridor, northwest China: Zooarchaeological and stable isotopic evidence
Authors: Li Xin , Wei Wenyu , Ma Minmin , Lu Minxia , Du Linyao , Yang Yishi , Chen Guoke , Ren Lele
Published: January 2023

The trajectory and influencing factors for changes to ancient human livelihoods in the Hexi Corridor of northwest China have been intensively discussed. The Hexi Corridor is a key crossroads for trans-Eurasian exchange in both the prehistoric and historical periods. Although most studies have focused on the reconstruction of human paleodiet and plant subsistence, the diachronic change of animal utilization strategies spanning the prehistoric and historical periods remains unclear, due to the absence of zooarchaeological and isotopic studies, especially in Han Dynasty (202 BCE–220 CE). Here we report new zooarchaeological, stable isotope, and radiocarbon dating data from the Heishuiguo Cemetery of the Han Dynasty in the Hexi Corridor, indicating that humans mainly used domestic chickens, pigs and sheep as funerary objects, with other buried livestock including cattle, horses and dogs. Stable carbon and nitrogen isotope data suggest humans might have fed chickens, pigs and dogs more C4 foods (likely millets or their byproducts) than herbivorous livestock in the Heishuiguo during the Han Dynasty. Compared to other prehistoric zooarchaeological and isotopic studies in the Hexi Corridor, we detected an increasing significance of herbivorous livestock in animal utilization strategies compared with omnivorous livestock, and a basic declining weight of C4 foods in fodders from ∼2,300 to 200 BCE, which was probably induced by long-distance exchange and climate fluctuation. However, the trend was reversed during the Han Dynasty in the Hexi Corridor, primarily due to the control of the area by the Han Empire and the subsequent massive immigration from the Yellow River valley of north China.
Study on stability of underlying room and pillar old goaf in close coal seam and mining of the upper coal seam
Authors: Liu Hongtao , Hao Cheng , Wang Zhiwen , Li Chong , Guo Linfeng , Liang Jialu , Wang Haozhu
Published: January 2023

Possible issues during mining of the upper coal seam in old goaf of nearby coal seams, including step subsidence, gas overflow in goaf, and roadway around rock fragmentation. Using the Hanjiawa Coal Mine’s upper coal seam mining, which takes place 28 m above the working face of the lower coal seam, as the research’s focal point. The paper focuses on the self-stability of the coal pillar in the old goaf, the failure form of the upper coal seam mining floor, the roof caving rule of the old goaf in the lower coal seam mining of the upper coal seam, and the bearing capacity of the interlayer rock strata using the pillar goaf stability evaluation system, field geological borehole electrical logging and borehole peeping, finite element difference numerical calculation, and other methods. The conclusion that the old goaf’s coal pillar can be completely stable and that the interlayer rock strata can bear the stress of upper coal seam mining is reached. The results show that the failure depth of the coal pillar in the lower coal seam old goaf is 1–3 m, the maximum failure depth accounting for 15% of the width of the coal pillar, and the failure depth of the roof in the old goaf is 0–3 m; After the mining of the upper coal seam, the floor above the coal pillar of the lower coal seam is plastic failure, and the failure depth is 1–10 m, and the failure depth of the roof of the old goaf of the lower coal seam is 3–15 m, which is 4 times greater than that before the mining. The maximum failure depth of the interlayer rock strata is 22 m, accounting for 78.6% of the rock strata spacing. The interlayer rock strata can bear the mining disturbance of the upper coal seam. The plastic zone of the floor of the upper coal seam is not connected with the plastic zone of the roof of the lower coal seam.
Hydrogeochemical characteristics and genesis of Hongshuilantang Hot Spring and its water temperature anomalies during the Rushan earthquake swarm in Eastern China
Authors: Du Guilin , Su Shujuan , Chang Xiangchun , Ren Hongwei , Huo Zhuqing , Zhang Xiaohui
Published: January 2023

Water temperatures of hot springs close to tectonic fault zones often show some variations before earthquakes, and analyses of earthquake precursors in hot springs have significant referential meaning for earthquake monitoring and forecasting. This study measured the concentration of major ions in water from the Hongshuilantang Hot Spring in 2017 and 2020. The ion composition was classified by hydrochemistry into the HCO3·SO4-Na chemical type. The composition of hydrogen and oxygen isotopes in the Hongshuilantang Hot Spring were located near the global meteoric water line (GMWL), indicating that the recharge source of the hot spring was meteoric water. The δD and δ18O values were not plotted on the Glogal Meteroric Water Line (GMWL), and there were some deviations, which suggested that hot spring water underwent water–rock interactions. Deep circulation water played an important role during the evolution process of thermal water. Water temperature showed a decreasing trend from October 2013 to June 2015 during the Rushan earthquake swarm in eastern China. Because of the occurrence of the earthquake swarm, we inferred that regional stress in this area began to be released, allowing continuous rebalancing. Free surface water appeared in some aquifers, and the seepage of low-temperature underground water into the upper aquifer led to a drop in water temperature in the hot spring. The Hongshuilantang Hot Spring and the epicenter of the Rushan earthquake swarm were located on the Muping–Jimo seismological fault zone, with the same seismotectonic system and some genesis relationships.
Gated recurrent unit neural network (GRU) based on quantile regression (QR) predicts reservoir parameters through well logging data
Authors: Yu Zhengjun , Sun Youzhuang , Zhang Junhua , Zhang Yongan , Liu Zhen
Published: January 2023

The prediction of reservoir parameters is the most important part of reservoir evaluation, and porosity is very important among many reservoir parameters. In order to accurately measure the porosity of the core, it is necessary to take cores for indoor experiments, which is tedious and difficult. To solve this problem, this paper introduces machine learning models to estimate porosity through logging parameters. In this paper, gated recurrent unit neural network based on quantile regression method is introduced to predict porosity. Porosity measurement is implemented by taking cores for indoor experiments. The data is divided into training set and test set. The logging parameters are used as the input parameters of the prediction model, and the porosity parameters measured in the laboratory are used as the output parameters. Experimental results show that the quantile regression method improves the accuracy of the gated recurrent unit neural network, and the RMSE (Root Mean Square Error) of the unoptimized GRU neural network is 0.1774, after optimization, the RMSE is 0.1061. By comparing with the most widely used BP neural network, the accuracy of the method proposed in this paper is much higher than that of BP neural network. This shows that the gated recurrent neural network method based on quantile regression is excellent in predicting reservoir parameters.
Spatiotemporal dynamics of vegetation in response to climate variability in the Borana rangelands of southern Ethiopia
Authors: Worku Mitiku Adisu , Feyisa Gudina Legese , Beketie Kassahun Ture , Garbolino Emmanuel
Published: January 2023

In this paper, we analyze the spatiotemporal dynamics of vegetation and its association with climate variables in the Borana rangelands of southern Ethiopia. Moderate resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) data, namely, MODIS/TERRA, MOD09Q1 16-day L3 Global 250 m Version 6 from National Aeronautics and Space Administration (NASA) United States Geological Survey (USGS), and climate data from 2000 to 2018 obtained from the National Meteorological Agency (NMA) of Ethiopia are used to determine the vegetation dynamics both at annual and seasonal timescales. The results indicate that the NDVI varies between .31 and .41, and the study area is dominated by sparse vegetation, especially shrubs and grasslands. The Borana rangelands were previously dominated by open grasslands, perennial herbaceous and woody vegetations, and some encroaching woody vegetations. The NDVI revealed poorer vegetation growth than the vegetation condition index (VCI) between 2000 and 2018, although variations were observed spatiotemporally. Rainfall was more highly variable both at annual and seasonal scales than the temperature during the studied years. The climate variables significantly determined the condition of vegetation, particularly during the growing seasons compared to other periods. A significant strong positive correlation was observed between the NDVI, VCI, and climate variables during the main (Belg) and short (Meher) rainy seasons in the Borana rangelands. The results of this study are beneficial for the development of proper intervention policies and provide information for sustainable rangeland management.