Nature Machine Intelligence
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2021
·Vol. 3
·期 3
·199-217
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IF 15.508
Roberts Michael,Driggs Derek,Thorpe Matthew,Gilbey Julian,Yeung Michael,Ursprung Stephan,Aviles-Rivero Angelica I.,Etmann Christian,McCague Cathal,Beer Lucian,Weir-McCall Jonathan R.,Teng Zhongzhao,Gkrania-Klotsas Effrossyni,Rudd James H. F.,Sala Evis,Schönlieb Carola-Bibiane
Machine learning methods offer great promise for fast and accurate detection and prognostication of coronavirus disease 2019 (COVID-19) from standard-of-care chest radiographs (CXR) and chest computed tomography (CT) images. Many articles have been published in 2020 describing new machine learning-based models for both of these tasks, but it is unclear which are of potential clinical utility. In this systematic review, we consider all published papers and preprints, for the period from 1 January 2020 to 3 October 2020, which describe new machine learning models for the diagnosis or prognosis of COVID-19 from CXR or CT images. All manuscripts uploaded to bioRxiv, medRxiv and arXiv along with all entries in EMBASE and MEDLINE in this timeframe are considered. Our search identified 2,212 studies, of which 415 were included after initial screening and, after quality screening, 62 studies were included in this systematic review. Our review finds that none of the models identified are of potential clinical use due to methodological flaws and/or underlying biases. This is a major weakness, given the urgency with which validated COVID-19 models are needed. To address this, we give many recommendations which, if followed, will solve these issues and lead to higher-quality model development and well-documented manuscripts.
研究领域:
医学影像学
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人工智能
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流行病学
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DOI
高影响因子
MOLECULAR PHARMACEUTICS
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2018
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IF 4.556
Hui Liu,Yuxiang Han,Jiyuan Li,Ming Qin,Qunfeng Fu,Chunhong Wang,Zhibo Liu
Amino acids derivative are well established molecular probes for diagnosis of a variety of cancer using positron emission tomography (PET). Recently, boramino acid (BAAs) was found as a prospective molecular platform for developing PET tracer. The objective of this study was to develop a 18F-labeled alanine derivative through displacing its carboxylate by trifluoroborate as a selective ASCT2 marker for cancer imaging. 18F-Ala-BF3 was first evaluated in healthy FVB/N mice in vivo, exhibiting rapid renal clearance with almost negligible uptake in stomach (1.53 ± 0.31%ID/g). Notable uptake was observed in thyroid (3.71 ± 0.49%ID/g, 40 min post injection), of which the uptake was significantly inhibited by co-injection with natural L-alanine. In addition, we further established 18F-Ala-BF3 on a human gastric cancer cell (BGC-823) xenografts bearing mouse model. Dynamic PET-CT scan revealed the optimal time window for tumor imaging, it was between 40 and 60 min post injection, when the BGC-823 xenografts uptake was 5.49 ± 1.47%ID/g (n = 4), and the tumor-to-stomach, tumor-to-blood, tumor-to-muscle, and tumor-to-brain ratios were 3.27 ± 1.53, 3.80 ± 1.48, 3.47 ± 1.48, and 6.20 ± 1.47, respectively.
研究领域:
医学影像学
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肿瘤学
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分子生物学
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DOI
PubMed
高影响因子
Materials
·
2023
·Vol. 16
·期 19
·6613
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IF 3.4
Lixiao Xiao,Jirui Hou,Weiju Wang,Infant Raj
This work focuses on the development of a novel high-temperature microemulsion for enhanced oil recovery in tight oil reservoirs. Microemulsions are a type of mixture that has properties of both liquids and solids; they have shown significant potential for improving oil recovery through spontaneous imbibition. Herein, a high-temperature-tolerant lower-phase microemulsion using a microemulsion dilution method was developed. The properties and morphological characteristics of the microemulsion were evaluated and proposed a mechanism for enhanced spontaneous imbibition oil recovery using imbibition tests and CT scanning technology. The results of the study showed that the optimum concentration of the microemulsion was 0.2 wt% and that it had good thermal stability, small droplet size, lower interfacial tension, good wettability alteration ability, and minimum adsorption loss. The imbibition and CT experiments demonstrated that the reduction in oil/solid adhesion was due to the synergistic effect of IFT reduction and wettability alteration and the ability to increase the imbibition distance through a larger self-driving force. The study concludes that the solubilization coefficient and self-driving force were defined and calculated to quantitatively analyze the imbibition mechanisms and the results showed that the reduction in oil/solid adhesion was due to the synergistic effect of IFT reduction and wettability alteration and the ability to increase the imbibition distance through a larger self-driving force.
研究领域:
石油工程
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化学工程
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产品关联
DOI
PubMed
高影响因子
Processes
·
2019
·Vol. 7
·期 3
·159
·
IF 1.963
Yahong Wu,Weiwei Luo,Xunan Jia,Haoqing Fang,Honggang Wang,Shuai Yu
We investigated the performance of viscoelastic surfactant (VES) solution when applied in treatment on the uninvaded matrix using core flooding tests to analyze the impact of VES/CaCl2concentration on fluid viscosity. In this paper, core samples from Tahe carbonate reservoir, with an average permeability less than 0.02 × 10−3μm−2and a small average porosity in the range of approximately 0.04–5.24% are used in the experiments. Computed tomography (CT) scanning is used to provide a detailed description of inner structure variation of cores after the acid system treatment. The results confirmed that a large pressure difference contributed to fracture propagation and the relative permeability of water increased significantly after the treatment. It was also found that higher concentrations of VES and/or Ca2+induced higher viscosity and a stronger fracturing effect, while a lower concentration improved the reaction rates and etching effect, generating small worm holes inside the core. Foam in-situ produced during the etching process is the major contributor to the fluid viscosity enhancement. The permeability of fracture formed on the surface of the core is more sensitive to the confining pressure. These findings can help better understand the rheological properties of the acid system and etching and fracturing mechanisms during acid treatment, and which provides instructions for field implementation.Keywords:VES/HCl solution;carbonate rock;acid etching;X-CT scan;filter loss;core flow experiment
研究领域:
石油工程
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地质学
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产品关联
DOI
高影响因子
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
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2024
·Vol. 50
·期 13
·10327-10344
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IF 2.6
Xu Ruifeng,Wang Shuoshi,Guo Ping,Hukuang Haoxiang,Yuan Na
The CO 2 -WAG injection method proposed for unconventional tight oil reservoirs has been successfully applied in field. However, for water-sensitive tight oil reservoirs, there is a lack of research focusing on the displacement mechanisms and effects of WAG injection at the pore scale. And the gap between nuclear magnetic resonance (NMR) and computerized tomography (CT) scanning technologies is not well explored. This study integrated deuterium oxide-shielded NMR and contrast agent (n-butane iodide and lead iso-octanoate mixture) enhanced micro-CT to study the immiscible CO 2 -WAG mechanisms for water-sensitive tight oil. The aim is to investigate the microscopic distribution and displacement mechanisms of residual oil after CO 2 flooding and WAG injection in water-sensitive cores. Experimental results showed that NMR experiments and CT experiments identified the microscopic distribution of oil at different injection stages successfully. The contrast agent, despite its similar viscosity ratio, had poor representativeness in other properties, leading to significant differences in the microscopic fluid distribution results compared to NMR experiments. The primary WAG flood mechanism observed was that CO 2 dispersed oil droplets, with most being displaced out of the pores, while water played a mobility control role by blocking large pores. However, due to water sensitivity, medium and small pores also experienced blockage, making the effect of WAG injection after CO 2 flooding not significant. In the NMR experiment, the final recovery of core 6–1 after WAG injection was 64.71%. In the CT scan experiment, due to the smaller volume of the microcore, the water sensitivity effect was relatively weaker, and under the stronger influence of the capillary end effect, the final recovery reached 76.91%. In the five sets of long-core experiments, by controlling the gas–water ratio and slug size, the recovery ranged from 56.51 to 64.04%. The core flood experiments validated the representativeness of the microscopic experiments. And for water-sensitive tight oil reservoirs, controlling the volumes of water and CO 2 during the WAG injection process is crucial.
研究领域:
石油工程
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油气田开发
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渗流力学
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岩石物理
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提高采收率
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2022
·
IF 8.025
Zewen Shi,Fang Yang,Qian Pang,Yiwei Hu,Haijian Wu,Xueqiang Yu,Xianjun Chen,Lin Shi,Bowen Wen,Rui Xu,Ruixia Hou,Dan Liu,Qingjiang Pang,Yabin Zhu
With the development of minimally invasive orthopedics, injectable materials for bone repair are attracted more attention, especially for those wound with a small external mouth and sizeable internal cavity. In this work, the hydrogel with features of thermo-responsiveness, degradability and injectability was designed and fabricated. The hydrogel, named as FHCS, is composed of Pluronic F-127 (F127) loaded with carboxymethyl chitosan/sodium alginate nanoparticles (nCS) and nanohydroxyapatite (nHA). The hydrogel FHCS was non-toxic and good hemocompatible. It can enhance the ALP activity and extracellular matrix calcification of MC3T3-E1 due to the chitosan-based nanoparticle components (nCS). Moreover, FHCS-5 (containing 5 mg/mL nCS) showed relative high expression of osteogenic genes and protein markers. Osteal regeneration was observed treated by FHCS-5 hydrogel in a critical-size rat calvarial bone defect model. CT scanning showed that the whole defect was basically covered by new bone after FHCS-5 hydrogel. The results of H&E staining and Masson's trichrome staining on histological sections further confirmed that FHCS-5 hydrogel promoted new osteal formation and maturation, which up regulated the osteogenic related genes and proteins of ALP, OCN, OPN through BMP/Smad signaling pathway. Hence, this study suggests that FHCS-5 hydrogels have a promising application for non-loading bone regeneration.
研究领域:
生物医学工程
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材料科学
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骨科
·
组织工程
✓ 已验证
DOI
PubMed
高影响因子
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