bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of Coal Seam Connectivity via Multi-Seam Pinpoint Fracturing Operations in the Walloons Coal Measures, Surat Basin
Authors: Pandey Vibhas J. , Ganpule Sameer , Dewar Steven
Published: April 2021

The Walloons coal measures located in Surat Basin (eastern Australia) is a well-known coal seam gas play that has been under production for several years. The well completion in this play is primarily driven by coal permeability which varies from 1 Darcy or more in regions with significant natural fractures to less than 1md in areas with underdeveloped cleat networks. For an economic development of the latter, fracturing treatment designs that effectively stimulate numerous and often thin coals seams, and enhance inter-seam connectivity, are a clear choice. Fracture stimulation of Surat basin coals however has its own challenges given their unique geologic and geomechanical features that include (a) low net to gross ratio of ~0.1 in nearly 300 m (984.3 ft) of gross interval, (b) on average 60 seams per well ranging from 0.4 m to 3 m in thickness, (c) non-gas bearing and reactive interburden, and (d) stress regimes that vary as a function of depth. To address these challenges, low rate, low viscosity, and high proppant concentration coiled tubing (CT) conveyed pinpoint stimulation methods were introduced basin-wide after successful technology pilots in 2015 (Pandey and Flottmann 2015). This novel stimulation technique led to noticeable improvements in the well performance, but also highlighted the areas that could be improved – especially stage spacing and standoff, perforation strategy, and number of stages, all aimed at maximizing coal coverage during well stimulation.

This paper summarizes the findings from a 6-well multi-stage stimulation pilot aimed at studying fracture geometries to improve standoff efficiency and maximizing coal connectivity amongst various coal seams of Walloons coal package. In the design matrix that targeted shallow (300 to 600 m) gas-bearing coal seams, the stimulation treatments varied in volume, injection rate, proppant concentration, fluid type, perforation spacing, and standoff between adjacent stages. Treatment designs were simulated using a field-data calibrated, log-based stress model. After necessary adjustments in the field, the treatments were pumped down the CT at injection rates ranging from 12 to 16 bbl/min (0.032 to 0.042 m3/s).

Post-stimulation modeling and history-matching using numerical simulators showed the dependence of fracture growth not only on pumping parameters, but also on depth. Shallower stages showed a strong propensity of limited growth which was corroborated by additional field measurements and previous work in the field (Kirk-Burnnand et al. 2015). These and other such observations led to revision of early guidelines on standoff and was considered a major step that now enabled a cost-effective inclusion of additional coal seams in the stimulation program. The learnings from the pilot study were implemented on development wells and can potentially also serve as a template for similar pinpoint completions worldwide.
Modeling Multistage Acid Fracturing Treatments in Carbonate Reservoirs
Authors: Dong Rencheng , Wheeler Mary F. , Su Hang , Ma Kang
Published: April 2021

As our industry is tapping into tighter carbonate reservoirs than in the past, completion techniques need to be improved to stimulate the low-permeability carbonate formation. Multistage acid fracturing technique has been developed in recent years and proved to be successful in some carbonate reservoirs. A multistage acid fracturing job is to perform several stages of acid fracturing along a horizontal well. The goal of acid fracturing operations is to create enough fracture roughness through differential acid etching on fracture walls such that the acid fracture can keep open and sustain a high enough acid fracture conductivity under the closure stress. In multistage acid fracturing treatments, acid flow is in a radial flow scenario and the acid etching process can be different from acid fracturing in vertical wells. In order to accurately predict the acid-fracture conductivity, a detailed description of the rough acid-fracture surfaces is required. In this paper, we developed a 3D acid transport model to compute the geometry of acid fracture for multistage acid fracturing treatments. The developed model couples the acid fluid flow, reactive transport and rock dissolution in the fracture. We also included acid viscous fingering in our model since viscous fingering mechanism is commonly applied in multistage acid fracturing to achieve non-uniform acid etching. Our simulation results reproduced the acid viscous fingering phenomenon observed from experiments in the literature. During the process of acid viscous fingering, high-conductivity channels developed in the fingering regions. We modeled the acid etching process in multistage acid fracturing treatments and compared it with acid fracturing treatments in vertical wells. We found that due to the radial flow effect, it is more difficult to achieve non-uniform acid etching in multistage acid fracturing treatments than in vertical wells. We investigated the effects of perforation design and pad fluid viscosity on multistage acid fracturing treatments. We need to have an adequate number of perforations in order to develop non-uniform acid etching. We found that a higher viscosity pad fluid helps acid to penetrate deeper in the fracture and result in a longer and narrower etched channel.
Machine Learning and Artificial Intelligence Provides Wolfcamp Completion Design Insight
Authors: Shelley Robert , Oduba Oladapo , Melcher Howard
Published: April 2021

The subject of this paper is the application of a unique machine learning approach to the evaluation of Wolfcamp B completions. A database consisting of Reservoir, Completion, Frac and Production information from 301 Multi-Fractured Horizontal Wolfcamp B Completions was assembled. These completions were from a 10-County area located in the Texas portion of the Permian Basin. Within this database there is a wide variation in completion design from many operators; lateral lengths ranging from a low of about 4,000 ft to a high of almost 15,000 ft, proppant intensities from 500 to 4,000 lb/ft and frac stage spacing from 59 to 769 ft.

Two independent self-organizing data mappings (SOM) were performed; the first on completion and frac stage parameters, the second on reservoir and geology. Characteristics for wells assigned to each SOM bin were determined. These two mappings were then combined into a reservoir type vs completion type matrix. This type of approach is intended to remove systemactic errors in measuement, bias and inconsistencies in the database so that more realistic assessments about well performance can be made. Production for completion and reservoir type combinations were determined. As a final step, a feed forward neural network (ANN) model was developed from the mapped data. This model was used to estimate Wolfcamp B production and economics for completion and frac designs.

In the performance of this project, it became apparent that the incorporation of reservoir data was essential to understanding the impact of completion and frac design on multi-fractured horizontal Wolfcamp B well production and economic performance. As we would expect, wells with the most permeability, higher pore pressure, effective porosity and lower water saturation have the greatest potential for hydrocarbon production. The most effective completion types have an optimum combination of proppant intensity, fluid intensity, treatment rate, frac stage spacing and perforation clustering.

This paper will be of interest to anyone optimizing hydraulically fractured Wolfcamp B completion design or evaluating Permian Basin prospects. Also, of interest is the impact of reservoir and completion characteristics such as permeability, porosity, water saturation, pressure, offset well production, proppant intensity, fluid intensity, frac stage spacing and lateral length on well production and economics. The methodology used to evaluate the impact of reservoir and completion parameters for this Wolfcamp project is unique and novel. In addition, compared to other methodologies, it is low cost and fast. And though the focus of this paper is on the Wolfcamp B Formation in the Midland Basin, this approach and workflow can be applied to any formation in any Basin, provided sufficient data is available.
Effectiveness and Safety of Bushen Huoxue in Treatment of Premature Ovarian Insufficiency: study protocol for a randomised, double-blinded, placebo-controlled and multicentre clinical trial
Authors: Cao Ying , Wang Juan Pei , Lu Yan , Chen Yue , Chen Si , Zhao Bo Wei
Published: April 2021

Introduction Premature Ovarian Insufficiency (POI) seriously affects the quality of life, endocrine function, and fertility of women of childbearing age. Currently, Hormone replacement therapy for POI has some limitations, either with low efficacies or high side effects. Bushen Huoxue (BSHX) plays an important role in alleviating clinical symptoms and improving health status of POI patients. This placebo-controlled, randomised, double-blind, and multicentre clinical trial protocol aims to evaluate the effectiveness and safety of BSHX in women with POI.Methods and Design We plan to recruit 150 women with POI from four participating hospitals in China. Participants will be randomised in a 1:1 to receive oral BSHX or BSHX placebo. All participants will be treated for 3-month and will be followed up for another 3-month. The primary outcome is questionnaire scores based on the changes in the total symptoms, which is the Chinese version of the Menopause-Specific Quality of Life (CMS)1. The other measurements include serum sex hormone levels, anti-mullerian hormone (AMH) levels, ovarian peak systolic velocity (PSV; cm/s), and antral follicle count (AFC). In this study, the regulatory effects of traditional Chinese medicine on hormones was evaluated by the changes of serum sex hormone levels, which include serum estradiol (E2), luteinizing hormone (LH), and follicle-stimulating hormone (FSH). Ethics and dissemination This study was approved by the Research Ethics Committee of Jiangsu Province Hospital on Integration of Chinese and Western Medicine (2019LWKY014). All participants will provide written informed consent prior to randomization. The results of this research will be presented to academic conferences and peer-reviewed journals.Trial registration number ChiCTR1900028451.Registered 22 December 2019, www.chictr.org.
Hilbert's First Problem and the New Progress of Infinity Theory
Authors: Wang Xijia
Published: April 2021

In the 19th century, Cantor created the infinite cardinal number theory based on the "1-1 correspondence" principle. The continuum hypothesis is proposed under this theoretical framework. In 1900, Hilbert made it the first problem in his famous speech on mathematical problems, which shows the importance of this question. We know that the infinitesimal problem triggered the second mathematical crisis in the 17-18th centuries. The Infinity problem is no less important than the infinitesimal problem. In the 21st century, Sergeyev introduced the Grossone method from the principle of "whole is greater than part", and created another ruler for measuring infinite sets. The development of the infinity theory provides new ideas for solving Hilbert's first problem, and provides a new mathematical foundation for Cosmic Continuum Theory.
Prediction of Soil-Water Characteristic Curve of Compacted Loess With Different Dry Densities Based on Nuclear Magnetic Resonance
Authors: yuan kangze , Ni Wan kui , LV Xiang-Fei , Li Xiang-ning , Wang Hai-man , Li Lan , Nie Yong-peng
Published: April 2021

Accurate determination of soil-water characteristic (SWCC) is of great importance for understanding the mechanical properties of unsaturated loess. In this study, the compacted loess columns with different dry densities were prepared. Moisture sensor, water potential sensor and nuclear magnetic resonance (NMR) were used to investigate the SWCC and NMR signals intesity of compacted loess under different dry densities. It has been found that with increasing dry density, the saturated water content and the residual water content gradually decreases, but the decrease in residual water content is smaller, and both can establish a linear relationship with dry density. The NMR results showed that the compacted loess pore volume gradually decreased with increasing dry density. When the dry density increased from 1.45 g/cm3 to 1.55 g/cm3, the pore volume of compacted loess decreased by 14.7%, while when the dry density increased from 1.55 g/cm3 to 1.65 g/cm3, the pore volume of compacted loess decreased by 13.2%. The Van Genuchten (VG) model was used to fit the NMR results and SWCC, and a good corresponding relationship was found between the parameters. Therefore, according to the cumulative NMR intensity parameters, SWCC was predicted under different dry densities and the effect was found very well.
How Does Economic Policy Uncertainty Affect CO2 Emissions? A Regional Analysis in China
Authors: Liu Yan , Zhang Zepeng
Published: April 2021

More recently, the COVID-19 pandemic outbreak has created massive economic policy uncertainty (EPU). EPU and its economic fallout have been a hot topic of study, however, the impact of EPU on CO2 emissions has been seldom addressed to date. This paper investigates the direct impact of the EPU on CO2 emissions and indirect effect via the environmental regulation at the national and regional levels using the panel data model and provincial panel data from 2003 to 2017 in China. The empirical results show that the central region is the most special one, which all explanatory variables except energy consumption are all non-significant even at the 10% level. For other samples, there is a significant positive correlation between EPU and CO2 emissions, whether in the national or regional level. Additionally, environmental regulation alone can achieve the purpose of curtailing carbon emissions. However, when the EPU is taken into consideration, environmental regulation exerts a significantly positive effect on CO2 emissions, leading to unintended increase in emissions. Moreover, the Environmental Kuznets Curve (EKC) hypothesis was confirmed in the national and eastern samples, while CO2 emissions increase monotonically as economic level grows for western datasets. Based on the overall findings, some policy implications were put forward.
Does the EU emissions trading system help reduce PM2.5 damage? A research based on PSM- DID method
Authors: Wan Liang , Wang Shanyong , Zang Jianing , Zheng Qiaoqiao , Fang Wenpei
Published: April 2021

Air quality, especially haze pollution, has become an important issue that threatens the sustainable development and health of human beings. To study and formulate effective environmental regulations to control and reduce the concentration of PM2.5 in the air, especially to clarify the effect of the relevant emission trading system on the emission reduction of air pollutants is a research topic with important practical significance and theoretical value. Previous studies on the environmental effects of emissions trading system (ETS) generally focused on carbon emission and their intensity, instead of focusing on the synergistic governance effects between ETS and PM2.5. Based on the PSM-DID method, this paper selects PM2.5 damage and other related data from 147 countries in the World Development Index (WDI) database. This paper examined whether the EU ETS has a spillover effect on PM2.5 damage reduction, and further discussed the related impact mechanisms and approaches. The research results show that the EU ETS has promoted the reduction of PM2.5 damage, and at different stages of implementation, the impact of the EU ETS on the reduction of PM2.5 damage has a dynamic effect. After discussion, it is found that ETS mainly affects PM2.5 emission reduction through two channels: pollution industry transfer, industrial structure upgrading and green technology innovation. Finally, this paper gives relevant policy suggestions, which can encourage companies to achieve carbon emission reduction targets while helping to reduce PM2.5 emissions, and eventually achieve a win-win situation between economic growth and environmental improvement.
A Rare Case With Arterial and Venous Thrombotic Complications After COVID-19
Authors: Songur Kadir , DILEK Banu , AYDEMIR Mustafa Dogukan , SAHIN Ebru , OZTURK Vesile , Gulbahar Selmin
Published: April 2021

Background
Recently, it has been reported that there is an increase in the incidence of arterial and venous thrombotic complications associated with severe COVID-19 disease. Studies have revealed the definition of COVID-19-associated coagulopathy as the underlying cause of these complications. With the emergence of hypercoagulability, systemic anticoagulant therapy was required at variable doses and durations in COVID-19 patients.
Case Report:
We present the case of a 79-year-old female patient who developed ischemic stroke, deep vein thrombosis, and acute pulmonary embolism, respectively, despite the use of anticoagulants since hospitalization for severe COVID-19 disease.
Discussion
Owing to SARS-CoV2 infection may be accompanied by comorbidities such as hypoxia, immobilization, active cancer, and obesity, close patient monitoring should be performed during the period of active disease and recovery.
Conclusion
The most important message to be taken from this case is that even in patients using anticoagulants, there is still a higher risk of thrombotic complications.
Facile stearoyl chloride grafted cotton filter fabric and its application in oil-water separation
Authors: He Yuan , Luo Yejun , Li Zheng , Yan Chao , Chen Yufang , Jin Tao
Published: April 2021

Chemical graft technology has been arisen widely interesting for its stronger chemical interaction between hydrophobic layers and substrates. Instead of coating technology based on physical function, chemical graft technology can produce hydrophobic membrane with more efficient durability for oil-water separation, which is essential in various industries like sewage treatment and oil spill. As cellulose-based material, cotton filter fabric is a flexible and degradable material with abundant hydroxyl groups, providing great possibility for graft reactions. Stearyl chloride has both hydrophobic alkyl chain and active acyl group, making it easily to be grafted onto cotton filter fabrics. Therefore, we propose to use stearyl chloride as hydrophobic layer and one-step modify cotton filter fabric. The obtained hydrophobic modified cotton filter fabric exhibits high contact angles (CAmax = 147o, CAavg = 141.8o), which only decrease slightly after 5 h droplet holding time (CAmax = 141o, CAavg = 126.3o). Besides, the modified sample also shows hydrophobic durability after three times gravity-drove oil-water filtration separation (CAmax = 137o, CAavg = 132.6o). This hydrophobic modified cotton filter fabric may have potential application in future oil-water separation and the stearyl chloride graft technology is an both effective and efficient way in hydrophobic modification.
Assessment of Pilot Direct Contact Membrane Distillation Regeneration of Lithium Chloride Solution in Liquid Desiccant Air-conditioning Systems Using Computer Simulation
Authors: Duong Hung Cong , Nghiem Long Duc , Ansari Ashley Joy , Vu Thao Dinh , Nguyen Khai Manh
Published: April 2021

Membrane distillation (MD) has been increasingly explored for treatment of various hyper saline waters, including lithium chloride (LiCl) solutions used in liquid desiccant air-conditioning (LDAC) systems. In this study, the regeneration of liquid desiccant LiCl solution by a pilot direct contact membrane distillation (DCMD) process is assessed using computer simulation. Unlike previous experimental investigations, the simulation allows to incorporate both temperature and concentration polarisation effects in the analysis of heat and mass transfer through the membrane, thus enabling the systematic assessment of the pilot DCMD regeneration of the LiCl solution. The simulation results demonstrate distinctive profiles of water flux, thermal efficiency, and LiCl concentration along the membrane under co-current and counter-current flow modes, and the pilot DCMD process under counter-current flow is superior to that under co-current flow regarding the process thermal efficiency and LiCl concentration enrichment. Moreover, for the pilot DCMD regeneration of LiCl solution under the counter-current flow, the feed inlet temperature, LiCl concentration, and especially the membrane leaf length exert profound impacts on the process performance: the process water flux halves from 12 to 6 L/(m2×h) while thermal efficiency decreases by 20% from 0.46 to 0.37 when the membrane leaf length increases from 0.5 to 1.5 m.
A Highly Efficient Adsorbent Based On Starch-Graphene Oxide Architecture For Scavenging Aqueous Pb(II): Isotherms, Kinetics, Thermodynamics And Interaction Mechanism
Authors: Guo Ting , Bulin Chaoke , Zhang Bangwen , Ma Zeyu , Xing Ruiguang , Ge Xin , Zhang Yanghuan , Li Bo
Published: April 2021

Heavy metal pollution stems from the modern industry is a severe environmental problem. In this work, a highly efficient adsorbent based on starch-graphene oxide architecture (SGO) was fabricated, characterized and employed to scavenge aqueous Pb(Π). The scavenging performance was evaluated, and the interaction mechanism between SGO and Pb(Π) was elucidated. Results indicate, the starch introduction brought performance enhancement, consequently made SGO outperform both single starch and GO in terms of adsorption efficiency. SGO adsorbs 95.83 % of Pb(Π) in 16 min, with adsorption capacity 383.32 mg•g− 1, manifesting some advantages over other analogous adsorbents, such as higher capacity and faster kinetics. The chemical interaction between Pb(OH)+ and C = O, C-O related groups in SGO supported the adsorption, which was a spontaneous, exothermic and entropy increasing process. The adsorption was well described by the Freundlich, pseudo-second-order model and Intra-particle diffusion models, both intra-particle diffusion and chemical interaction were the rate controlling steps. Based on its high adsorption efficiency, SGO may have promising application in heavy metal scavenging from water.
Health Beneficial Effects and Chemical Profiles of Special Oolong Teas
Authors: Rujanapun Narawadee , Jaidee Wuttichai , Duangyod Thidarat , Phuneerub Pravaree , Wattanasiri Chakree , Paojumroom Napassawan , Maneerat Tharakorn , Pringpuangkeo Chuchawal , Charoensup Rawiwan
Published: April 2021

Background: Tea blended with medicinal plants usually consists of a mixture of active compounds that can increase the beneficial health effects. Eternity tea is dried tea leaves blended with ginger (Zingiber officinale), lemongrass (Cymbopogon citratus), and celery (Apium graveolens L.), and peaceful rest tea is dry tea leaves blended with Indian gooseberry (Phyllanthus emblica), Turkey berry (Solanum torvum Swartz), and wild betel leaf bush leaves (Piper sarmentosum Roxb.). These teas have been widely used for their ability to reduce blood sugar levels. However, there are no previous reports on their pharmacological activities. This work investigates the chemical profiles and pharmacological activities, especially the antidiabetes activity, of special oolong teas blended with local Thai medicinal plants (peaceful rest tea and eternity tea).Method: Eternity, Peaceful rest, and Oolong (Camellia sinensis) leaf samples were collected from Doi Chang organic tea plantation in Chiang Rai, Thailand. The chemical profiles of all tea samples were characterized by UHPLC-QTOF-MS. The extracts of these teas were investigated for their biological activities, including antioxidant, antiinflammatory, anticancer, and antidiabetic activities.Results: Catechins were found in eternity and oolong teas. Peaceful rest tea contained catechins/dimeric catechins, flavonoid glycosides, and alkaloids. Biological testing showed that peaceful rest and eternity tea extracts inhibited nitric oxide formation in a dose-dependent manner with IC50 values of 42.6 and 48.9 µg/mL, respectively. Peaceful rest tea extracts inhibited the growth of K562 human erythroleukemia cells. Furthermore, peaceful rest tea with both ethanol and water extracts demonstrated higher α-glucosidase inhibition activities than acarbose (IC50 = 75.71 µg/mL), with IC50 values of 10.6 and 1.22 µg/mL, respectively.Conclusions: Major antidiabetic compounds (5-O-Caffeoylquinic acid, kaempferol 3-O-glucosylrutinoside, and procyanidin B2) were found in peaceful rest tea. This finding corroborates that peaceful rest tea has greater antidiabetic effects than other teas against glucose and lipid levels. In vivo and clinical studies are therefore recommended to provide implications for the potential anti-diabetic properties of special oolong teas.
Integrated Treatment of Mining Dam Wastewater With Quaternized Chitosan and Pan/hpmc/agno3 Nanostructured Hydrophylic Membranes
Authors: Bigogno Rodrigo Gonçalves , Dias Marcos Lopes , Manhães Mariana Borges N. , Rodriguez Ruben J. Sanchez
Published: April 2021

This study was developed a novel nanostructured membrane by electrospinning process, from polyacrylonitrile (PAN) modify by hydroxypropyl methylcellulose (HPMC) polymers containing AgNO3, to be used as a filter in an integrated wastewater dam treatment process to reuse it as drinking water. Different formulations (108 samples) were electrospun from PAN and (0, 5, 10%w) HPMC and (0, 0.5, 1%w) solutions to selected a more efficient formulation in water disinfection and higher hydrophilic character of the membrane to flow performance in the wastewater treatment. The PAN and HPMC phases in membranes were characterize by infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The nanostructured membranes (SEM) were characterized by thickness fiber between 251 ± 58 and 306 ± 49 nm and lower fiber/membrane volume relations. The presence of HPMC and AgNO3 in membrane formulation endows superhydrophilicity and permeability increase which up to 21,151 ± 445 L.m-2.h-1. After filtration process with PAN/HPMC/AgNO3, all the tested water potability indexes were achieved. The primary treatment, using quaternized chitosan reduced the turbidity parameter from 19,000 NTU to 14 NTU, and after filtration with nanostructured membrane, to levels was below 1 NTU and pathogenic potential removed (Total Coliform and Escherichia coli). The results of this study indicated that the hydrophilic nanostructured membranes PAN/10%HPMC/1%AgNO3 have adequate properties to potential wastewater treatment mining for reuse. It´s give a sustainable strategy for managing wastewater which should be reduce the volume of water in the tailing’s dams and contributes to increasing the stability of dams and reducing risks with catastrophic environmental impact.
Skin liquid biopsy method for assessing the immune environment of cutaneous T-cell lymphoma lesions
Authors: Torii Kan , Okada Yukinori , Morita Akimichi
Published: April 2021

(179/200 words) Detailed analysis of cells infiltrating lesional skin cannot be performed in skin biopsy specimens by immunohistochemistry or cell separation techniques because small amounts of protein and minor cell populations in the biopsy specimen might be destroyed by enzyme treatment in the isolation step. Here, we describe a skin liquid biopsy method that enables T cell isolation in small amounts of lesional whole blood from patients with cutaneous T-cell lymphoma. Lesional blood, assumed to contain lesional resident cells, cells from capillary vessels, and blood overflowing from capillary vessels in the lesion area, was obtained during regular skin biopsy. The lesional blood showed substantial increases in distinct cell populations, chemokines, and expression of various genes. CD8 + CD45RO + T cells in the lesional blood negatively correlated with the modified severity-weighted assessment tool scores. CD4 + CD45RO + T cells in the lesional blood expressed genes associated with the development of cancer and progression of cutaneous T-cell lymphoma. The skin liquid biopsy technique might provide new insight into the pathogenesis of mycosis fungoides and facilitate evaluation of the treatment efficacy for other skin inflammatory diseases.
Relationship Between PD-L1 Expression, CD8+ T-Cell Infiltration and Prognosis in Intrahepatic Cholangiocarcinoma Patients
Authors: Deng Min , Li Shao-Hua , Fu Xu , Yan Xiao-Peng , Chen Jun , Qiu Yu-Dong , Guo Rong-Ping
Published: April 2021

Background: Programmed death- ligand 1(PD-L1) seems to be associated with the immune escape of tumors, and immunotherapy may be a favorable treatment for PD-L1-positive patients. We evaluated ICC specimens for their expression of PD-L1, infiltration of CD8+ T cells, and the relationship between these factors and patient survival.Methods: In total, 69 resections of ICC were stained by immunohistochemistry for PD-L1, programmed death factor-1(PD-1), and CD8+ T cells. CD8+ T-cell densities were analyzed both within tumors and at the tumor-stromal interface. Patient survival was predicted based on the PD-L1 status and CD8+ T-cell density.Results: The expression rate of PD-L1 was 12% in cancer cells and 51% in interstitial cells. The expression rate of PD-1 was 30%, and the number of CD8+ T-cells increased with the increase of PD-L1 expression (p<0.05). The expression of PD-L1 in the tumor was correlated with poor overall survival(OS) (p=0.004), and the number of tumor and interstitial CD8+ T-cells was correlated with poor OS and disease-free survival (DFS) (All p<0.001).Conclusions: The expression of PD-L1 in the tumor is related to poor OS, and the number of tumor or interstitial CD8+ T-cells is related to poor OS and DFS. For patients who lose their chance of surgery, PD-L1 immunosuppressive therapy may be the focus of future research as a potential treatment.
Mapping Patterns of Para-aortic Lymph Node Recurrence in Cervical Cancer: A Retrospective Cohort Analysis
Authors: Bae Bong Kyung , Park Shin-Hyung , Jeong Shin Young , Chong Gun Oh , Kim Mi Young , Kim Jae-Chul
Published: April 2021

Background: To map anatomic patterns of para-aortic lymph node (PALN) recurrence in cervical cancer patients and validate currently available guidelines on PA clinical target volumes (CTV).Methods: Cervical cancer patients who developed PALN recurrence were included. The PALNs were classified as left-lateral para-aortic (LPA), aorto-caval (AC), and right para-caval (RPC). Four PA CTVs were contoured for each patient to validate PALN coverage. CTVRTOG was contoured based on the Radiation Therapy Oncology Group guideline. CTVK was contoured as proposed by Keenan et al. CTVM was contoured by expanding symmetrical margins around the aorta and inferior vena cava of 7 mm up to the T12–L1 interspace. CTVnew was created by modifying CTVRTOG to obtain better coverage.Results: We identified 92 PALNs in 35 cervical cancer patients. 46.8% of the PALNs were at LPA, 38.0% were at AC, and 15.2% were at RPC areas. CTVRTOG, CTVK, and CTVM covered 87.0%, 88.0%, and 62.0% of all PALNs, respectively. PALN recurrence above the left renal vein was associated with PALN involvement at diagnosis (p = 0.043). Extending upper border to the superior mesenteric artery allowed the CTVnew to cover 96.7% of all PALNs and all nodes in 91.4% of patients.Conclusion: CTVRTOG and CTVK encompassed most PALN recurrences. For high-risk patients, such as those having PALN involvement at diagnosis, extending the superior border of CTV from the left renal vein to superior mesenteric artery could be considered.
Engineering oxygen vacancies in Na2Ti3O7 for boosting its catalytic performance in MgH2 hydrogen storage
Authors: Zhang Huanhuan , Kong Qianqian , Hu Song , Zhang Dafeng , Chen Haipeng , Xu Chunbao (Charles) , Li Baojun , Fan Yanping , Liu Baozhong
Published: April 2021

Rational design of high-efficiency catalysts plays a critical role in improving the hydrogen storage performances of the MgH2. Herein, flower-like Na2Ti3O7 catalyst with rich oxygen vacancies (Na2Ti3O7-Ov) was synthesized from Ti3C2-MXene and demonstrated to remarkably enhance the hydrogen storage of MgH2. Specifically, with an addition of 5 wt.% Na2Ti3O7-Ov, the initial dehydrogenation temperature of the MgH2 + 5Na2Ti3O7-Ov composite reduced substantially from 287 °C (for MgH2) to 183 °C. Moreover, the MgH2 + 5Na2Ti3O7-Ov composite exhibited fast hydrogen ab/desorption kinetics and superb reversible hydrogen storage performance with a retention rate of 90.1 % after 10 cycles attributed to the higher structural stability of Na2Ti3O7-Ov. Both experimental and theoretical results confirm that the oxygen vacancies in Na2Ti3O7-Ov reduce the reaction activation energy during MgH2 dehydrogenation, hence accounting for the excellent hydrogen sorption kinetics. This work would lead to new design and development of advanced defect-based nano-catalysts for the MgH2 hydrogen storage system.
Loss of nuclear envelope phosphatase CTDNEP1 drives aggressive medulloblastoma by triggering MYC amplification and genomic instability
Authors: Luo Zaili , Liao Yunfei , Xin Dazhuan , Berry Kalen , Ogurek Sean , Dong Xinran , Li Hao , Yu Jianzhong , Zhang Feng , Han Ron , Dong Chen , Xia Mingyang , Xu Lingli , Lin Yifeng , Ye Chang , Zhang Liguo , Huang Guoying , Zhou Wenhao , Xin Mei , hu xiaohua , Zhao Chuntao , Rao Rohit , Nishinakamura Ryuichi , Yu Jiyang , Kool Marcel , Pfister Stefan , Roussel Martine , Weiss William A , Andreassen Paul , Lu Q. Richard
Published: April 2021

MYC-driven medulloblastomas are highly aggressive childhood brain tumors, however, the genetic events triggering MYC amplification and malignant transformation remain elusive. Here we report that mutations in CTDNEP1, a CTD nuclear-envelope-phosphatase, are the most significantly enriched recurrent alterations in MYC-driven medulloblastomas, and define high-risk subsets with poorer prognosis. CTDNEP1 ablation transforms murine cerebellar progenitors into MYC-amplified medulloblastomas, resembling their human counterparts. CTDNEP1 deficiency stabilizes MYC protein by elevating MYC serine-62 phosphorylation, and triggers genomic instability with eventual MYC amplification and p53 loss. Further, phosphoproteomics reveals that CTDNEP1 post-translationally modulates the activities of key regulators for proper chromosome segregation and mitotic checkpoints including topoisomerase TOP2A and checkpoint kinase CHEK1. Co-targeting CHEK1 and MYC activities synergistically inhibits CTDNEP1-deficient MYC-amplified tumor growth and prolongs animal survival. Together, our studies identify CTDNEP1 acting as a tumor suppressor in highly aggressive medulloblastomas by maintaining homeostatic MYC levels and genomic stability, highlighting a CTDNEP1-dependent therapeutic vulnerability.
lncRNA-Disease Association Prediction Based On Weight Matrix And Projection Score
Authors: Wang Bo , Zhang Chao , Du Xiao-xin , Zhang Jian-fei
Published: April 2021

Background: with the development of medical science, lncRNA, originally considered as a noise gene, has been found to participate in a variety of biological activities. Nowadays, more and more studies show that lncRNA is involved in various human diseases, such as gastric cancer, prostate cancer, lung cancer, etc. However, obtaining lncRNA-disease association only through biological experiments not only costs manpower and material resources, but also gains little. Therefore, it is very important to develop effective computational models for predicting lncRNA-disease association. Results: In this paper, a new lncRNA-disease association prediction model LDAP-WMPS based on weight distribution and projection score is proposed. Based on the existing research results of disease semantic similarity, the integrated lncRNA similarity matrix and the integrated disease similarity matrix are calculated according to the disease semantic similarity and the association information between data. On this basis, the weight algorithm is combined with the improved projection algorithm to predict the lncRNA-disease association through the known lncRNA-miRNA association and miRNA-disease association. The simulation results show that under the loocv framework, the AUC of LDAP-WMPS can reach 0.8822. Better than the latest results. Through the case study of adenocarcinoma and colorectal cancer, it is proved that LDAP-WMPS can effectively infer lncRNA-disease association. Conclusions: The simulation results show that LDAP-WMPS has good prediction performance, which is an important supplement to the research of lncRNA-disease association prediction without lncRNA-disease association data. Keywords: lncRNA-miRNA association, miRNA-disease association, disease semantic similarity, Integrated lncRNA similarity, integrated disease similarity, Weight allocation algorithm, Projection score.
Sex-differences in COVID-19 associated excess mortality is not exceptional for the COVID-19 pandemic. A population based study from 27 European countries
Authors: Nielsen Jens , Nørgaard Sarah , Lanzieri Giampaolo , Vestergaard Lasse , Moelbak Kaare
Published: April 2021

Background

Europe experienced increased mortality from February through June, 2020 due to the COVID-19 pandemic, with more COVID-19-associated deaths in males compared to females. However, a sex-difference in excess mortality may be a more general phenomenon, and should be investigated in none-COVID-19 situations as well.
Methods

Based on death counts from Eurostat, separate excess mortalities were estimated for each of the sexes using the EuroMOMO algorithm. Sex-differences were expressed as differences in excess mortality incidence rates. A general relation between sex-differences and overall excess mortality both during the COVID-19 pandemic and in preceding seasons were investigated.
Results

Data from 27 European countries were included, covering the seasons 2016/17 to 2019/20. In periods with increased excess mortality, excess was consistently highest among males. From February through May 2020 male excess mortality was 52.7 (95% PI: 56.29; 49.05) deaths per 100,000 person years higher than for females. Increased male excess mortality compared to female was also observed in the seasons 2016/17 to 2018/19. We found a linear relation between sex-differences in excess mortality and overall excess mortality, i.e., 40 additional deaths among males per 100 excess deaths per 100,000 population. This corresponds to an overall female/male mortality incidence ratio of 0.7.
Conclusion

In situations with overall excess mortality, excess mortality increases more for males than females. We suggest that the sex-differences observed during the COVID-19 pandemic reflects a general sex-disparity in excess mortality.
Numerical study of bio-convection flow of magneto-Cross nanofluid containing gyrotactic microorganisms with effective Prandtl number approach
Authors: Hamid Aamir , Khan M. Ijaz , Kumar R. Naveen , Gowda R. J. Punith , Prasannakumara B.C.
Published: April 2021

In this study, a mathematical model is developed to scrutinize the transient magnetic flow of Cross nanoliquid past a stretching sheet with thermal radiation effects. Binary chemical reactions and heat source/sink effects along with convective boundary condition are also taken into the consideration. Apposite similarity transformations are utilized to transform partial differential equations (PDE’s) into ordinary ones and then numerically tackled by shooting method. The Impacts of different emerging parameters on the thermal, concentration, velocity, and micro-rotation profiles are incorporated and discussed in detail by means of graphs. Results reveals that, the escalation in Magnetic parameter and Rayleigh number slowdowns the velocity and momentum of the fluid. The increase in Biot number, radiation and Heat sink/source parameters upsurges the thermal boundary but, converse trend is seen for escalating Prandtl number. The density number of motile microorganisms acts as a growing function of bioconvection Lewis number and declining function of bioconvection Peclet number.
New temperature and oxygen fugacity data of Martian nakhlite from Northwest Africa (NWA) 5790 and implications for sulphur degassing depth
Authors: Wang Zilong , Tian Wei
Published: April 2021

Newly analysed titanomagnetite–ilmenite (Tim–Ilm) intergrowths from Martian nakhlite meteorite Northwest Africa (NWA) 5790 yielded crystallisation temperature up to 1032°C and oxygen fugacity (fO2) up to ΔQFM + 1.6, notably higher than previous estimates for nakhlite magmas (temperature < 950°C, fO2 = ΔQFM-1 to ΔQFM + 1). To interpret how the magma was reduced from ΔQFM-1 to ΔQFM + 1.6, we used D-Compress to model the sulphur degassing process. For fO2 to significantly decrease in this extended range, the sulphur-rich Martian magma had to degas all the sulphur species at a certain final degassing pressure, which was 2–4 bar for NWA 988 and Lafayette and < 0.7 bar for Y-000593 and Nakhla. These final degassing pressure data are in good agreement with the Martian nakhlite burial depth estimated by other petrological and geochemical methods. These estimates are also comparable with the excavation depth of ~ 40 m based on the small (6.5 km in diameter) impact crater over the Elysium lava plain. The fO2-controlled sulphur degassing pressure may constitute a method for estimating the burial depth of sulphur-rich lava flows on Mars.
Efficient Crowd Counting Model using Feature Pyramid Network and ResNeXt
Authors: G Kalyani , B Janakiramaiah , L.V Narasimha Prasad , A Karuna , A Mohan Babu
Published: April 2021

Crowd counting is one of the most challenging issues in computer vision community for safety and security through surveillance systems. It has extensive range of applications, such as disaster management, surveillance event detection, intelligence gathering and analysis, public safety control, trafﬁc monitoring, design of public spaces, anomaly detection and military. Early approaches still encounter many issues, like non-uniform density distribution, partial occlusion and discrepancies in scale and point of view. To address the above problems, Feature Pyramid Networks are introduced in deep convolution networks for counting the individuals in the Crowd. The designed network has extracted the features at all resolutions and is constructed rapidly from only one input image. This method achieves out-performance results compared to the well-known networks on three demanding standard crowd counting datasets.
Characterization of Thrust Force, Temperature, Chip Morphology and Power in Ultrasonic-assisted Drilling of Aluminium 6061
Authors: Moghaddas Amin
Published: April 2021

In this study, a special resolution V design and Response surface methodology (RSM) were used to characterize the ultrasonic-assisted drilling (UAD) process of Aluminum 6061. This characterization was done through developing mathematical models to study the effect of ultrasonic and drilling parameters including spindle speed, feed rate and amplitude on thrust force, temperature, chip morphology and power. The tests were done using an industrially hardened non-rotating UAD system mounted in a CNC turning center. The analysis of variance (ANOVA) was used to find significant parameters of thrust force, temperature, chip morphology and power. Then, for all responses, the optimum drilling parameters that provide desired solutions for all responses were obtained. This was followed by out-of-sample testing to verify the accuracy of the developed models. The results of this study showed that in UAD of aluminum, the minimum values of thrust force and chip size were obtained at low spindle speed, low feed rate and high amplitude. The results also showed that amplitude was not a significant parameter affecting the tool temperature and cannot be used to analyze the effect of ultrasonic vibrations on generated heat during UAD. Instead, the interaction of amplitude and feed rate was significant and should be considered in the analysis. Finally, minimum consumed power, specially at higher amplitudes, can be obtained using high spindle speed and low feed rate.
A Comparison of Infectious Outcomes Between In-Office Transperineal Prostate Biopsies Without Antibiotic Prophylaxis and Transrectal Prostate Biopsies
Authors: Islam Majdee , Silva Rodrigo Donalisio Da , Quach Alan , Gustafson Diedra , Nogueira Leticia , Clark Nathan , Kim Fernando J.
Published: April 2021

Background: To describe our experience with office-based transperineal biopsy (TPB) without antibiotics compared to transrectal biopsy (TRB) with antibiotics and bowel preparation. The literature elicits comparable cancer detection, time, and cost between the two. As antibiotic resistance increases, antimicrobial stewardship is imperative. Methods: In our retrospective review, we compared the TPB to TRB in our institution for in-office prostate biopsies with local anesthesia from 06/2017-06/2019. Patients had negative urinalysis on day of procedure. Patients presenting with symptoms concerning for UTI followed by positive urine culture were determined to have a UTI. Results: Two hundred twenty-two patients met inclusion criteria. Age, race, BMI, pre-procedure PSA, history of UTI, BPH or other GU history were similar between both groups. Two TPB patients (1.8%) had post-procedure UTI; one received oral antibiotics and one received a dose of intravenous and subsequent oral antibiotics. There were no sepsis events or admissions. Six TRB patients (5.4%) had post-procedure UTI; five received oral antibiotics, and one received intravenous antibiotics and required admission for sepsis. One TPB patient (0.9%) had post-procedure retention and required catheterization, while four TRB patients (3.6%) had retention requiring catheterization. No significant difference noted in cancer detection between the two groups. Conclusion: In-office TPB without antibiotic prophylaxis/bowel prep is comparable to TRB in regard to safety and cancer detection. TPB without antibiotics had a lower infection and retention rate than TRB with antibiotics. Efforts to reduce antibiotic resistance should be implemented into daily practice. Future multi-institutional studies can provide further evidence for guideline changes.