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Simulation of the Ecosystem Productivity Responses to Aerosol Diffuse Radiation Fertilization Effects over the Pan-Arctic during 2001–19 被引量:1
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作者 Zhiding ZHANG Xu YUE +3 位作者 Hao ZHOU Jun ZHU Yadong LEI Chenguang TIAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期84-96,共13页
The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).Whil... The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).While such DRFEs have been explored at low to middle latitudes,the aerosol impacts on pan-Arctic ecosystems and the contributions by anthropogenic and natural emission sources remain less quantified.Here,we perform regional simulations at 0.2o×0.2ousing a well-validated vegetation model(Yale Interactive terrestrial Biosphere,YIBs)in combination with multi-source of observations to quantify the impacts of aerosol DRFEs on the net primary productivity(NPP)in the pan-Arctic during 2001-19.Results show that aerosol DRFEs increase pan-Arctic NPP by 2.19 Pg C(12.8%)yr^(-1)under clear-sky conditions,in which natural and anthropogenic sources contribute to 8.9% and 3.9%,respectively.Under all-sky conditions,such DRFEs are largely dampened by cloud to only 0.26 Pg C(1.24%)yr^(-1),with contributions of 0.65% by natural and 0.59% by anthropogenic species.Natural aerosols cause a positive NPP trend of 0.022% yr^(-1)following the increased fire activities in the pan-Arctic.In contrast,anthropogenic aerosols induce a negative trend of-0.01% yr^(-1)due to reduced emissions from the middle latitudes.Such trends in aerosol DRFEs show a turning point in the year of 2007 with more positive NPP trends by natural aerosols but negative NPP trends by anthropogenic aerosols thereafter.Though affected by modeling uncertainties,this study suggests a likely increasing impact of aerosols on terrestrial ecosystems in the pan-Arctic under global warming. 展开更多
关键词 diffuse radiation fertilization effects anthropogenic aerosols natural aerosols pan-Arctic net primary productivity
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Transition from a filamentary mode to a diffuse one with varying distance from needle to stream of an argon plasma jet
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作者 许慧敏 高敬格 +3 位作者 贾鹏英 冉俊霞 陈俊宇 李金懋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期539-544,共6页
Plasma jet has extensive application potentials in various fields, which normally operates in a diffuse mode when helium is used as the working gas. However, when less expensive argon is used, the plasma jet often ope... Plasma jet has extensive application potentials in various fields, which normally operates in a diffuse mode when helium is used as the working gas. However, when less expensive argon is used, the plasma jet often operates in a filamentary mode. Compared to the filamentary mode, the diffuse mode is more desirable for applications. Hence, many efforts have been exerted to accomplish the diffuse mode of the argon plasma jet. In this paper, a novel single-needle argon plasma jet is developed to obtain the diffuse mode. It is found that the plasma jet operates in the filamentary mode when the distance from the needle tip to the central line of the argon stream(d) is short. It transits to the diffuse mode with increasing d. For the diffuse mode, there is always one discharge pulse per voltage cycle, which initiates at the rising edge of the positive voltage. For comparison, the number of discharge pulse increases with an increase in the peak voltage for the filamentary mode. Fast photography reveals that the plasma plume in the filamentary mode results from a guided positive streamer,which propagates in the argon stream. However, the plume in the diffuse mode originates from a branched streamer, which propagates in the interfacial layer between the argon stream and the surrounding air. By optical emission spectroscopy,plasma parameters are investigated for the two discharge modes, which show a similar trend with increasing d. The diffuse mode has lower electron temperature, electron density, vibrational temperature, and gas temperature compared to the filamentary mode. 展开更多
关键词 plasma jet diffuse mode filamentary mode optical emission spectroscopy
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Extragastrointestinal stromal tumors with diffuse membranous distribution with bleeding:A case report
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作者 Jian-Duo Xu Zheng Wang +3 位作者 Qian Zhou Ning Meng Shu-Mei Zhang Nan Liu 《World Journal of Clinical Cases》 SCIE 2024年第26期5990-5997,共8页
BACKGROUND Extragastrointestinal stromal tumors(EGIST)and gastrointestinal stromal tumors are of similar pathological type and form.Here we report a rare case of EGIST diffusely distributed in membranous tissue in abd... BACKGROUND Extragastrointestinal stromal tumors(EGIST)and gastrointestinal stromal tumors are of similar pathological type and form.Here we report a rare case of EGIST diffusely distributed in membranous tissue in abdominal cavity,the feature of which included diffuse tumors at membranous tissue in entire abdominal cavity and spontaneous bleeding of the tumors.CASE SUMMARY The patient was a 71-year man and hospitalized due to continuous pain at lower abdomen for more than 10 days.Upon physical examination,the patient had flat and tough abdomen with mild pressing pain at lower abdomen,no obvious abdominal mass was touchable,and shifting dullness was positive.Positron emission tomography-computed tomography(CT)showed that in his peritoneal cavity,there were multiple nodules of various sizes,seroperitoneum,multiple enlarged lymph nodes in abdominal/pelvic cavity and right external ilium as well as pulmonary nodules.Plain CT scanning at epigastrium/hypogastrium/pelvic cavity+enhanced three-dimensional reconstruction revealed multiple soft tissue nodules in abdominal/pelvic cavity,peritoneum and right groin.Tumor marker of carbohydrate antigen 125 was 808 U/mL,diffuse tuberous tumor was seen in abdominal/pelvic cavity during operation with hematocelia,and postoperative pathological examination confirmed EGIST.Imatinib was administered with better therapeutic effect.CONCLUSION Gene testing showed breast cancer susceptibility gene 1 interacting protein C-terminal helicase 1 and KIT genovariation,and the patient was treated with imatinib follow-up visit found that his clinical symptoms disappeared and the tumor load alleviated obviously via imageological examination. 展开更多
关键词 diffuse tumor in abdominal cavity Extragastrointestinal stromal tumors Gastrointestinal stromal tumors Malignant extragastrointestinal stromal tumors diffusely membranous metastasis
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Influence of bias voltage and oxygen addition on the discharge aspects of a diffuse argon plume in an atmospheric pressure plasma jet
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作者 Pengying JIA Guoxin HAN +6 位作者 Xiupin DONG Kaiyue WU Junxia RAN Xuexia PANG Xuexue ZHANG Jiacun WU Xuechen LI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第12期75-81,共7页
A remote plasma,also referred to as a plasma plume(diffuse or filamentary),is normally formed downstream of an atmospheric pressure plasma jet.In this study,a diffuse plume is formed by increasing the bias voltage(U_(... A remote plasma,also referred to as a plasma plume(diffuse or filamentary),is normally formed downstream of an atmospheric pressure plasma jet.In this study,a diffuse plume is formed by increasing the bias voltage(U_(b))applied to the downstream electrode of an argon plasma jet excited by a negatively pulsed voltage.The results indicate that the plume is filamentary when U_(b)is low,which transits to the diffuse plume with increasing U_(b).The discharge initiated at the rising edge of the pulsed voltage is attributed to the diffuse plume,while that at the falling edge contributes to the filament in the plume.For the diffuse plume,the discharge intensity decreases with the increasing oxygen content(C_o).Fast photography reveals that the diffuse plume results from a negative streamer,which has a dark region near the nozzle with C_o=0%.However,the dark region is absent with C_o=0.5%.From the optical emission spectrum,the electron density,electron excitation temperature,gas temperature,and oxygen atom concentration are investigated. 展开更多
关键词 atmospheric pressure plasma jet diffuse plasma plume optical emission spectrum
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InternDiffuseDet:结合可变形卷积和扩散模型的目标检测方法 被引量:1
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作者 袁志祥 高永奇 《计算机工程与应用》 CSCD 北大核心 2024年第12期203-215,共13页
针对现有目标检测中存在的漏检和误检、特征提取能力有限、处理复杂场景时检测精度不高等问题,基于DiffusionDet进行改进,提出了一种结合可变形卷积和扩散模型的目标检测方法。以模型在进入检测头之前需要更多且优质的特征图为核心思想... 针对现有目标检测中存在的漏检和误检、特征提取能力有限、处理复杂场景时检测精度不高等问题,基于DiffusionDet进行改进,提出了一种结合可变形卷积和扩散模型的目标检测方法。以模型在进入检测头之前需要更多且优质的特征图为核心思想,在主干网络中引入InternImage和DCNv3可变形卷积算子提升模型的感受野和非线性建模能力。对中间层的FPN特征金字塔进行改进,设计了一种基于选择性加权的特征金字塔CS-FPN;利用深度可分离卷积实现通道和区域的分离,同时采用CARAFE算子替代传统的上采样操作,提高分辨率和语义信息的传递;随后利用SGE注意力机制对特征图进行重组,以确保特征图在扩散的过程中保留更多的层次化信息。在特征图进入检测头之前,进行DDIM的扩散操作,获得不同时刻的特征图,以扩充检测特征图的数量。最后在目标框匹配和损失函数方面采用EIOU算法以处理目标框之间的位置偏移和尺度差异。实验数据显示,在COCO数据集和道路检测数据集上,改进后的模型在相同的实验环境下比原有模型分别提升了3.8和3.6个百分点。实验结果表明该方法在提高目标检测的准确性和鲁棒性方面具有一定的潜力,并为解决现实场景中的目标检测问题提供了新的思路和方法。 展开更多
关键词 diffusionDet 可变形卷积 扩散模型 特征金字塔 损失函数
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RPRD1B/CREPT facilitates the progression of diffuse large B-cell lymphoma by inhibiting apoptosis through the NF-κB signaling pathway
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作者 Lu Xu Zhi-Hao Xie +5 位作者 Jun Li Shi Tao Fang-Li Ren Yin-Yin Wang Zhi-Jie Chang Xin-Bao Hao 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第7期307-318,共12页
Objective:To investigate the role of RPRD1B in the progression of diffuse large B-cell lymphoma(DLBCL)and its potential as a therapeutic target.Methods:This study analyzed RPRD1B expression in DLBCL and normal tissues... Objective:To investigate the role of RPRD1B in the progression of diffuse large B-cell lymphoma(DLBCL)and its potential as a therapeutic target.Methods:This study analyzed RPRD1B expression in DLBCL and normal tissues using public databases and assessed its prognostic impact through survival analysis.In vitro and in vivo experiments were conducted to explore the mechanisms by which RPRD1B influences tumor growth and apoptosis.Results:RPRD1B expression was significantly elevated in DLBCL compared to normal tissues and was associated with poor prognosis.In vitro and in vivo experiments demonstrated that RPRD1B promoted lymphoma cell proliferation and inhibited apoptosis through the NF-κB signaling pathway.Conclusions:RPRD1B plays a critical role in the progression of DLBCL by modulating apoptosis and cellular proliferation.Targeting RPRD1B may offer a novel therapeutic strategy for DLBCL,suggesting its potential as a prognostic marker and therapeutic target in hematological malignancies. 展开更多
关键词 RPRD1B RNAPⅡ diffuse large B-cell lymphoma NF-ΚB APOPTOSIS
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Identifying relevant factors influencing cancer-related fatigue in patients with diffuse large B-cell lymphoma during chemotherapy
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作者 Xiu-Qiao Hao Xiang-Dan Yang Yue Qi 《World Journal of Psychiatry》 SCIE 2024年第7期1017-1026,共10页
BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is a rapidly growing malignant tumor,and chemotherapy is one of the treatments used to combat it.Although advancements of science and technology have resulted in more and... BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is a rapidly growing malignant tumor,and chemotherapy is one of the treatments used to combat it.Although advancements of science and technology have resulted in more and more patients being able to receive effective treatment,they still face side effects such as fatigue and weakness.It is important to thoroughly investigate the factors that contribute to cancer-related fatigue(CRF)during chemotherapy.AIM To explore the factors related to CRF,anxiety,depression,and mindfulness levels in patients with DLBCL during chemotherapy.METHODS General information was collected from the electronic medical records of eligible patients.Sleep quality and mindfulness level scores in patients with DLBCL during chemotherapy were evaluated by the Pittsburgh Sleep Quality Index and Five Facet Mindfulness Questionnaire-Short Form.The Piper Fatigue Scale was used to evaluate the CRF status.The Self-Rating Anxiety Scale and Self-Rating Depression Scale were used to evaluate anxiety and depression status.Univariate analysis and multivariate regression analysis were used to investigate the factors related to CRF.RESULTS The overall average CRF level in 62 patients with DLBCL during chemotherapy was 5.74±2.51.In 25 patients,the highest rate of mild fatigue was in the cognitive dimension(40.32%),and in 35 patients the highest moderate fatigue rate in the behavioral dimension(56.45%).In the emotional dimension,severe fatigue had the highest rate of occurrence,34 cases or 29.03%.The CRF score was positively correlated with cancer experience(all P<0.01)and negatively correlated with cancer treatment efficacy(all P<0.01).Tumor staging,chemotherapy cycle,self-efficacy level,and anxiety and depression level were related to CRF in patients with DLBCL during chemotherapy.CONCLUSION There was a significant correlation between CRF and perceptual control level in patients.Tumor staging,chemotherapy cycle,self-efficacy level,and anxiety and depression level influenced CRF in patients with DLBCL during chemotherapy. 展开更多
关键词 diffuse large B-cell lymphoma CHEMOTHERAPY Cancer-related fatigue ANXIETY DEPRESSION MINDFULNESS
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Formation of diffuse and spark discharges between two needle electrodes with the scattering of particles
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作者 Victor F TARASENKO Dmitry V BELOPLOTOV +1 位作者 Alexei N PANCHENKO Dmitry A SOROKIN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期32-39,共8页
The development of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark decay.Positive and ... The development of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark decay.Positive and negative nanosecond voltage pulses with an amplitude of tens of kilovolts were applied.Time-resolved images of the discharge development were taken with a fourchannel Intensified Charge Coupled Device(ICCD)camera.The minimum delay between the camera channels could be as short as≈0.1 ns.This made it possible to study the gap breakdown process with subnanosecond resolution.It was observed that a wide-diameter streamer develops from the high-voltage pointed electrode.The ionization processes near the grounded pin electrode started when the streamer crossed half of the gap.After bridging the gap by the streamer,a diffuse discharge was formed.The development of spark leaders from bright spots on the surface of the pointed electrodes was observed at the next stage.It was found that the rate of development of the spark leader is an order of magnitude lower than that of the wide-diameter streamer.Long thin luminous tracks were observed against the background of a discharge plasma glow.It has been established that the tracks are adjacent to brightly glowing spots on the electrodes and are associated with the flight of small particles. 展开更多
关键词 needle electrodes short voltage pulses atmospheric air streamer breakdown diffuse and spark discharges scattering metal particles
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基于Diffusers框架的电商产品图制作方法研究
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作者 伍海洋 马川越 刘登辉 《无线互联科技》 2024年第2期104-106,共3页
基于Diffusers框架与Control Net网络,文章开发并实现了服装产品图的制作流程,将Segment Anything与Grounding DINO结合,实现了自动分割衣服蒙版。将Semantic Segmentation与ViTmatte结合,实现了对皮肤的精细化分割。文章使用大模型的... 基于Diffusers框架与Control Net网络,文章开发并实现了服装产品图的制作流程,将Segment Anything与Grounding DINO结合,实现了自动分割衣服蒙版。将Semantic Segmentation与ViTmatte结合,实现了对皮肤的精细化分割。文章使用大模型的低秩适应实现了对图像风格的微调,利用Ultralytics框架,结合Diffusers提出了一种图像修复方法。将生成图与原图对比,实验结果表明:将Diffusers与Control Net网络结合,能够实现模特替换与背景替换,该方法可以为用户提供衣服上身的参考,降低商家的产品图制作成本。 展开更多
关键词 电商产品图 模特替换 diffuseRS Control Net
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Association of overall survival benefit of radiotherapy with progression-free survival after chemotherapy for diffuse large B-cell lymphoma:A systematic review and meta-analysis
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作者 Jingnan Wang Xin Liu +21 位作者 Yunpeng Wu Qiuzi Zhong Tao Wu Yong Yang Bo Chen Hao Jing Yuan Tang Jing Jin Yueping Liu Yongwen Song Hui Fang Ningning Lu Ning Li Yirui Zhai Wenwen Zhang Min Deng Shulian Wang Fan Chen Lin Yin Chen Hu Shunan Qi Yexiong Li 《Journal of the National Cancer Center》 2024年第3期249-259,共11页
Objective:To evaluate whether improved progression-free survival(PFS)from radiotherapy(RT)translates into an overall survival(OS)benefit for diffuse large B-cell lymphoma(DLBCL).Methods:A systematic literature search ... Objective:To evaluate whether improved progression-free survival(PFS)from radiotherapy(RT)translates into an overall survival(OS)benefit for diffuse large B-cell lymphoma(DLBCL).Methods:A systematic literature search identified randomized controlled trials(RCTs)and retrospective studies that compared combined-modality therapy(CMT)with chemotherapy(CT)alone.Weighted regression analyses were used to estimate the correlation between OS and PFS benefits.Cohen’s kappa statistic assessed the consis-tency between DLBCL risk-models and PFS patterns.Furthermore,the benefit trend of RT was analyzed by fitting a linear regression model to the pooled hazard ratio(HR)according to the PFS patterns.Results:For both 7 RCTs and 52 retrospective studies,correlations were found between PFS HR(HRPFS)and OS HR(HROS)at trial level(r=0.639-0.876),and between PFS and OS rates at treatment-arm level,regardless of CT regimens(r=0.882-0.964).Incorporating RT into CT increased about 18%of PFS,and revealed a different OS benefit profile.Patients were stratified into four CT-generated PFS patterns(>80%,>60-80%,>40-60%,and≤40%),which was consistent with risk-stratified subgroups(kappa>0.6).Absolute gain in OS from RT ranged from≤5%at PFS>80%to about 21%at PFS≤40%,with pooled HROS from 0.70(95%CI,0.51-0.97)to 0.48(95%CI,0.36-0.63)after rituximab-based CT.The OS benefit of RT was predominant in intermediate-and high-risk patients with PFS≤80%.Conclusion:We demonstrated a varied OS benefit profile of RT to inform treatment decisions and clinical trial design. 展开更多
关键词 diffuse large B-cell lymphoma CHEMOTHERAPY RADIOTHERAPY Risk-benefit
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GAN与Diffusion在传统纹样设计中的实验研究
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作者 李莉 毛子晗 +2 位作者 吕思奇 袁晨旭 彭玉旭 《丝绸》 CAS CSCD 北大核心 2024年第8期9-22,共14页
传统纹样是中国优秀传统文化的重要组成部分,传统人工设计已经无法满足纹样的现代设计需求,生成式AI为传统纹样设计提供了新的设计路径和方法。文章将生成式AI应用于传统纹样设计中,通过适配实验优选基于GAN的Style GAN和基于Diffusion... 传统纹样是中国优秀传统文化的重要组成部分,传统人工设计已经无法满足纹样的现代设计需求,生成式AI为传统纹样设计提供了新的设计路径和方法。文章将生成式AI应用于传统纹样设计中,通过适配实验优选基于GAN的Style GAN和基于Diffusion的Stable Diffusion两种主流图像生成模型进行实验,采用技术分析与艺术分析相结合,对实验结果进行多角度、多维度对比分析,为设计师选择生成设计方法提供参照。实验结果表明,两个模型均能满足基本的艺术设计需求。Style GAN模型生成的纹样图像更接近真实图像的分布,具有更高的图像质量和多样性;Stable Diffusion模型能较好地传承传统纹样的基因,艺术性与创造性兼具,更加符合传统纹样的艺术设计需求。 展开更多
关键词 GAN diffusION 传统纹样 评价指标 对比分析 实验研究
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Does the intracoronary pressure differ according to two types(diffuse or focal)of coronary spasm? 被引量:1
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作者 Hiroki Teragawa Chikage Oshita Yuko Uchimura 《World Journal of Cardiology》 2023年第1期1-12,共12页
BACKGROUND Several reports show that two types of coronary vasospasm(diffuse and focal spasm)are associated with the severity or prognosis of coronary spasm in patients with vasospastic angina(VSA).It is unclear wheth... BACKGROUND Several reports show that two types of coronary vasospasm(diffuse and focal spasm)are associated with the severity or prognosis of coronary spasm in patients with vasospastic angina(VSA).It is unclear whether intracoronary pressure differs between the two spasm types.AIM To investigate such relationships using a pressure wire during the spasm provocation test(SPT)in patients with VSA.METHODS Eighty-seven patients with VSA(average age:67 years;50 men,37 women)underwent SPT.During the SPT,a pressure wire was advanced into the distal portion of the right coronary artery and left anterior descending coronary artery,and the ratio of the intracoronary pressure to the aortic pressure(Pd/Pa)was continuously monitored.An SPT was performed using acetylcholine(ACh),and the presence of coronary spasm was defined as the presence of>90%arterial narrowing in response to an ACh infusion,with the usual chest symptoms and/or ischemic ECG changes.Focal spasm was defined as total or subtotal spasm within one segment of the AHA classification,while diffuse spasm was defined as>90%spasm with two or more segments.RESULTS Among 87 patients,the frequencies of metabolic syndrome and having coronary atherosclerosis were higher in the focal group(n=33)than in the diffuse spasm group(n=54,P<0.05).In the vessel analyses,in these 134 spastic segments,diffuse and focal spasms were detected in 100 and 34 vessels,respectively.The Pd/Pa at baseline was similar in both groups(diffuse:0.96±0.05,focal:0.95±0.05,P=0.35);however,the Pd/Pa during coronary spasm was lower in focal spastic vessels(0.66±0.20)than in diffuse spastic vessels(0.76±0.11,P<0.01),and the reduction in Pd/Pa during an SPT was also lower in focal spastic vessels(-0.29±0.20)than in diffuse spastic vessels(-0.18±0.11,P<0.01).The presence of focal spasm was a significant factor responsible for reduction in Pd/Pa during SPT.CONCLUSION These findings suggest that focal spasm may be more severe than diffuse spasm,judging from the intracoronary pressure during coronary spasm. 展开更多
关键词 ACETYLCHOLINE Intracoronary pressure diffuse or focal spasm Vasospastic angina
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基于Stable Diffusion的虚拟人形象预设计的应用与研究 被引量:2
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作者 曾建勇 沈晓萍 《现代信息科技》 2024年第3期169-175,共7页
对当前AIGC在虚拟形象预设计方面的现状及影响进行了分析和探讨。以Stable Diffusion为例,详细介绍了工程构建和实现,对相关模块的作用、运行环境、使用方法及其指令等多个方面进行了综合叙述、分析和探讨,针对使用不同采样方法、不同... 对当前AIGC在虚拟形象预设计方面的现状及影响进行了分析和探讨。以Stable Diffusion为例,详细介绍了工程构建和实现,对相关模块的作用、运行环境、使用方法及其指令等多个方面进行了综合叙述、分析和探讨,针对使用不同采样方法、不同采样参数及不同训练模型生成图片效果的优劣进行了说明及展示。随后,通过项目实例,完整地展示了人物形象预设计的过程。最后,对AIGC等新技术可能带来的社会影响进行了预测和总结。 展开更多
关键词 AI生成内容 Stable diffusion 生成对抗网络 提示词 虚拟人形象
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Diffusion and reaction mechanism of limestone and quartz in fluxed iron ore pellet roasting process 被引量:1
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作者 Yufeng Guo Jinlai Zhang +5 位作者 Shuai Wang Jianjun Fan Haokun Li Feng Chen Kuo Liu Lingzhi Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期485-497,共13页
The increase to the proportion of fluxed pellets in the blast furnace burden is a useful way to reduce the carbon emissions in the ironmaking process.In this study,the interaction between calcium carbonate and iron or... The increase to the proportion of fluxed pellets in the blast furnace burden is a useful way to reduce the carbon emissions in the ironmaking process.In this study,the interaction between calcium carbonate and iron ore powder and the mineralization mechanism of fluxed iron ore pellet in the roasting process were investigated through diffusion couple experiments.Scanning electron microscopy with energy dispersive spectroscopy was used to study the elements’diffusion and phase transformation during the roasting process.The results indicated that limestone decomposed into calcium oxide,and magnetite was oxidized to hematite at the early stage of preheating.With the increase in roasting temperature,the diffusion rate of Fe and Ca was obviously accelerated,while the diffusion rate of Si was relatively slow.The order of magnitude of interdiffusion coefficient of Fe_(2)O_(3)-CaO diffusion couple was 10^(−10) m^(2)·s^(−1) at a roasting temperature of 1200℃for 9 h.Ca_(2)Fe_(2)O_(5) was the initial product in the Fe_(2)O_(3)-CaO-SiO_(2) diffusion interface,and then Ca_(2)Fe_(2)O_(5) continued to react with Fe_(2)O_(3) to form CaFe_(2)O_(4).With the expansion of the diffusion region,the sillico-ferrite of calcium liquid phase was produced due to the melting of SiO_(2) into CaFe_(2)O_(4),which can strengthen the consolidation of fluxed pellets.Furthermore,andradite would be formed around a small part of quartz particles,which is also conducive to the consolidation of fluxed pellets.In addition,the principle diagram of limestone and quartz diffusion reaction in the process of fluxed pellet roasting was discussed. 展开更多
关键词 fluxed iron ore pellet LIMESTONE HEMATITE QUARTZ diffusion reaction
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Value of multiple models of diffusion-weighted imaging to predict hepatic lymph node metastases in colorectal liver metastases patients 被引量:1
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作者 Hai-Bin Zhu Bo Zhao +3 位作者 Xiao-Ting Li Xiao-Yan Zhang Qian Yao Ying-Shi Sun 《World Journal of Gastroenterology》 SCIE CAS 2024年第4期308-317,共10页
BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindicatio... BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindication for liver resection.Up to now,there’s still lack of reliable preoperative methods to assess the status of hepatic lymph nodes in patients with CRLM,except for pathology examination of lymph node after resection.AIM To compare the ability of mono-exponential,bi-exponential,and stretchedexponential diffusion-weighted imaging(DWI)models in distinguishing between benign and malignant hepatic lymph nodes in patients with CRLM who received neoadjuvant chemotherapy prior to surgery.METHODS In this retrospective study,97 CRLM patients with pathologically confirmed hepatic lymph node status underwent magnetic resonance imaging,including DWI with ten b values before and after chemotherapy.Various parameters,such as the apparent diffusion coefficient from the mono-exponential model,and the true diffusion coefficient,the pseudo-diffusion coefficient,and the perfusion fraction derived from the intravoxel incoherent motion model,along with distributed diffusion coefficient(DDC)andαfrom the stretched-exponential model(SEM),were measured.The parameters before and after chemotherapy were compared between positive and negative hepatic lymph node groups.A nomogram was constructed to predict the hepatic lymph node status.The reliability and agreement of the measurements were assessed using the coefficient of variation and intraclass correlation coefficient.RESULTS Multivariate analysis revealed that the pre-treatment DDC value and the short diameter of the largest lymph node after treatment were independent predictors of metastatic hepatic lymph nodes.A nomogram combining these two factors demonstrated excellent performance in distinguishing between benign and malignant lymph nodes in CRLM patients,with an area under the curve of 0.873.Furthermore,parameters from SEM showed substantial repeatability.CONCLUSION The developed nomogram,incorporating the pre-treatment DDC and the short axis of the largest lymph node,can be used to predict the presence of hepatic LNM in CRLM patients undergoing chemotherapy before surgery.This nomogram was proven to be more valuable,exhibiting superior diagnostic performance compared to quantitative parameters derived from multiple b values of DWI.The nomogram can serve as a preoperative assessment tool for determining the status of hepatic lymph nodes and aiding in the decision-making process for surgical treatment in CRLM patients. 展开更多
关键词 Colorectal cancer Individualized treatment diffusion magnetic resonance imaging Intravoxel incoherent motion LIVER
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Does Diffuse Circumnuclear Gas around Sgr A^(*) Achieve Collisional Ionization Equilibrium or Remain Non-equilibrium Ionization?
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作者 Shu Niu Fu-Guo Xie +1 位作者 Wei Sun Li Ji 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期103-116,共14页
The feeding and feedback processes at the vicinity of a supermassive black hole(BH)are essential for our understanding of the connection between supermassive BH and its host galaxy.In this work,we provide a detailed i... The feeding and feedback processes at the vicinity of a supermassive black hole(BH)are essential for our understanding of the connection between supermassive BH and its host galaxy.In this work,we provide a detailed investigation,both observational and theoretical,on the diffuse(~2"-20",~0.08-0.8 pc)X-ray emission around Sgr A*.Over two-decade Chandra observations are gathered to obtain highest signal-to-noise to date.We find that,the line center of iron lines of the outer 8"-18"region,ε_(c)=6.65+0.02-0.03 keV,is comparable to that(ε_(c)=6.60+0.05-0.03 keV)of the inner 2"-5"region.This is somewhat unexpected,since the gas temperature decreases further away from the central BH.Based on a dynamical inflow-outflow model that considers the gas feeding by stellar winds from Wolf-Rayet stars,we calculate the X-ray spectrum based on both the conventional collisional ionization equilibrium(CIE)assumption,and the newly developed non-equilibrium ionization(NEI)assumption.We find that,theoretically gases within~8"-10"remain in a CIE state,outside of this radius they will be in the NEI state.A comparison of the properties of~6.6 keV iron lines between CIE and NEI is addressed.Interestingly,the NEI interpretation of outer region is supported by the Chandra line center ε_(c) measurements of this region. 展开更多
关键词 X-rays diffuse background-galaxies active-Galaxy center-(galaxies:)quasars emission lines
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Dihydroartemisinin enhances cell apoptosis in diffuse large B cell lymphoma by inhibiting the STAT3 activity
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作者 ZHENG CAO CHUNXIAO ZHOU +5 位作者 ZHIMIN WU CHUNYAN WU WEN ZHANG SHILV CHEN XINDONG ZHAO SHAOLING WU 《BIOCELL》 SCIE 2023年第5期1075-1083,共9页
Background:Dihydroartemisinin(DHA)is reported to be a potential anticancer agent,and the mechanisms underlying the effects of DHA on diffuse large B cell lymphoma however are still obscure.This study aimed to assess t... Background:Dihydroartemisinin(DHA)is reported to be a potential anticancer agent,and the mechanisms underlying the effects of DHA on diffuse large B cell lymphoma however are still obscure.This study aimed to assess the antitumor effect of DHA on diffuse large B cell lymphoma cells and to determine the potential underlying mechanisms of DHA-induced cell apoptosis.Methods:Here,the Cell Counting Kit 8 assay was conducted to study cell proliferation.We performed Annexin V-FITC/propidium iodide staining,real-time polymerase chain reaction,and western blot analysis to analyze cell apoptosis and potential molecular mechanisms.Results:The results showed that DHA substantially suppressed cell proliferation and induced cell apoptosis in vitro in a time-and concentration-dependent fashion.Moreover,STAT3 activity could be inhibited after stimulation with DHA.Conclusion:These results imply that the underlying anti-tumoral effect of DHA may increase apoptosis in diffuse large B cell lymphoma cells via the STAT3 signaling pathway.In addition,DHA might be an effective drug for diffuse large B cell lymphoma therapy. 展开更多
关键词 diffuse large B cell lymphoma DIHYDROARTEMISININ STAT3 Cell apoptosis
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Young thoracic vertebra diffuse idiopathic skeletal hyperostosis with Scheuermann disease:A case report
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作者 Wen-Zheng Liu Zheng-Qi Chang Zhe-Ming Bao 《World Journal of Clinical Cases》 SCIE 2023年第3期655-661,共7页
BACKGROUND Diffuse idiopathic skeletal hyperostosis(DISH)is a disorder characterised by the calcification and ossification of ligaments and entheses.It is a frequent occurrence in elderly males,but rarely encountered ... BACKGROUND Diffuse idiopathic skeletal hyperostosis(DISH)is a disorder characterised by the calcification and ossification of ligaments and entheses.It is a frequent occurrence in elderly males,but rarely encountered in younger individuals.CASE SUMMARY A 24-year-old male was admitted to the hospital due to low back pain accompanied with numbness in both lower limbs for 10 d.Upon clinical examination and imaging tests,the patient was diagnosed with DISH with Scheuermann disease and thoracic spinal stenosis.Before the operation and medical treatment,the patient had hypoesthesia of the skin below the xiphoid process.Afterward,a standard laminectomy was conducted using ultrasonic bone curette and internal fixation was applied.Subsequently,the patient was given corticosteroids,neurotrophic drugs,hyperbaric oxygen and electric stimulation.As a result of the treatment,the patient’s sensory level decreased to the navel level and there was no major change in the muscle strength of the lower limbs.During follow-up,the patient’s skin sensation has returned to normal.CONCLUSION This case is a rare instance of DISH co-existing with Scheuermann’s disease in a young adult.This provides a valuable reference point for spine surgeons,as DISH is more commonly observed in middle-aged and elder adults. 展开更多
关键词 diffuse idiopathic skeletal hyperostosis Scheuermann disease Thoracic spinal stenosis Case report
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Helicobacter pylori eradication treatment for primary gastric diffuse large B-cell lymphoma:A single-center analysis
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作者 Makoto Saito Akio Mori +7 位作者 Sayaka Kajikawa Emi Yokoyama Minoru Kanaya Koh Izumiyama Masanobu Morioka Takeshi Kondo Zen-Ichi Tanei Ai Shimizu 《World Journal of Clinical Cases》 SCIE 2023年第27期6424-6430,共7页
BACKGROUND Unlike the already established effect of Helicobacter pylori(H.pylori)eradication on gastric mucosa-associated lymphoid tissue(MALT)lymphoma,its therapeutic effect on primary gastric diffuse large B-cell ly... BACKGROUND Unlike the already established effect of Helicobacter pylori(H.pylori)eradication on gastric mucosa-associated lymphoid tissue(MALT)lymphoma,its therapeutic effect on primary gastric diffuse large B-cell lymphoma(DLBCL)is still unclear.AIM To clarify the efficacy of H.pylori eradication treatment for primary gastric DLBCL.METHODS We reported on 3 new cases,and added them to 3 previously reported cases.We analyzed the usefulness of H.pylori eradication treatment for gastric DLBCL for a total of 6 cases at our center.RESULTS Of the 6 patients(27-90 years old,3 males and 3 females),all 3 patients with single lesions(one transformed from MALT lymphoma)achieved complete remission(CR)after H.pylori eradication.Regarding the 2 newly reported cases,CR was maintained for more than 6 years with eradication treatment alone.In contrast,none of the 3 patients with 2 lesions achieved CR.In 1 newly reported case,endoscopic CR was achieved in one lesion,while stable disease was obtained in the other lesion.Two patients with progressive disease responded to standard chemo therapy±radiation and remained in CR for more than 6 years.CONCLUSION We believe it is worthwhile to attempt H.pylori eradication for elderly patients with primary gastric DLBCL in a single lesion with a small tumor burden. 展开更多
关键词 Primary gastric diffuse large B-cell lymphoma TREATMENT Helicobacter pylori ERADICATION
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Sodium Diffuses from Glass Substrates through P1 Lines and Passivates Defects in Perovskite Solar Modules
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作者 Felix Utama Kosasih Francesco Di Giacomo +13 位作者 Jordi Ferrer Orri Kexue Li Elizabeth M.Tennyson Weiwei Li Fabio Matteocci Gunnar Kusch Narges Yaghoobi Nia Rachel A.Oliver Judith L.MacManus-Driscoll Katie L.Moore Samuel D.Stranks Aldo Di Carlo Giorgio Divitini Caterina Ducati 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期393-401,共9页
Most thin-film photovoltaic modules are constructed on soda-lime glass(SLG)substrates containing alkali oxides,such as Na_(2)O.Na may diffuse from SLG into a module's active layers through P1 lines,an area between... Most thin-film photovoltaic modules are constructed on soda-lime glass(SLG)substrates containing alkali oxides,such as Na_(2)O.Na may diffuse from SLG into a module's active layers through P1 lines,an area between a module's constituent cells where the substrate-side charge transport layer(CTL)is in direct contact with SLG.Na diffusion from SLG is known to cause several important effects inⅡ-Ⅵand chalcogenide solar modules,but it has not been studied in perovskite solar modules(PSMs).In this work,we use complementary microscopy and spectroscopy techniques to show that Na diffusion occurs in the fabrication process of PSMs.Na diffuses vertically inside P1 lines and then laterally from P1 lines into the active area for up to 360 pm.We propose that this process is driven by the high temperatures the devices are exposed to during CTL and perovskite annealing.The diffused Na preferentially binds with Br,forming Br-poor,l-rich perovskite and a species rich in Na and Br(Na-Br)close to P1 lines.Na-Br passivates defect sites,reducing non-radiative recombination in the perovskite and boosting its luminescence by up to 5×.Na-Br is observed to be stable after 12 weeks of device storage,suggesting long-lasting effects of Na diffusion.Our results not only point to a potential avenue to increase PSM performance but also highlight the possibility of unabated Na diffusion throughout a module's lifetime,especially if accelerated by the electric field and elevated temperatures achievable during device operation. 展开更多
关键词 defect passivation monolithic interconnection perovskite solar modules soda-lime glass sodium diffusion solar cells thin-film photovoltaics
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