The electrophysical property of saturated rocks is very important for reservoir identification and evaluation. In this paper, the lattice Boltzmann method (LBM) was used to study the electrophysical property of rock...The electrophysical property of saturated rocks is very important for reservoir identification and evaluation. In this paper, the lattice Boltzmann method (LBM) was used to study the electrophysical property of rock saturated with fluid because of its advantages over conventional numerical approaches in handling complex pore geometry and boundary conditions. The digital core model was constructed through the accumulation of matrix grains based on their radius distribution obtained by the measurements of core samples. The flow of electrical current through the core model saturated with oil and water was simulated on the mesoscopic scale to reveal the non-Archie relationship between resistivity index and water saturation (I-Sw). The results from LBM simulation and laboratory measurements demonstrated that the I-Sw relation in the range of low water saturation was generally not a straight line in the log-log coordinates as described by the Archie equation. We thus developed a new equation based on numerical simulation and physical experiments. This new equation was used to fit the data from laboratory core measurements and previously published data. Determination of fluid saturation and reservoir evaluation could be significantly improved by using the new equation.展开更多
BACKGROUND Splenic artery aneurysm(SAA)rupture is a rare,life-threatening condition characterized by acute intra-abdominal hemorrhage and hemodynamic instability.Ruptured SAAs may exhibit a biphasic and relatively slo...BACKGROUND Splenic artery aneurysm(SAA)rupture is a rare,life-threatening condition characterized by acute intra-abdominal hemorrhage and hemodynamic instability.Ruptured SAAs may exhibit a biphasic and relatively slow clinical progression,commonly referred to as the“double-rupture phenomenon”.The reported incidence of the double-rupture phenomenon ranges 12%-21%in patients with ruptured SAAs,potentially due to variations in intra-abdominal pressure.Following anesthesia induction,muscle relaxation can decrease intra-abdominal pressure,potentially triggering the double-rupture phenomenon and leading to circulatory collapse.CASE SUMMARY A 61-year-old female presented to the Department of Emergency with upper abdominal pain,abdominal distension,dizziness,and vomiting.Her vital signs were initially stable.Physical examination revealed abdominal tenderness and positive-shifting dullness.Abdominal contrast-enhanced computed tomography revealed cirrhosis,severe portal hypertension,and splenomegaly.Acute rupture was suggested by a hematoma on the upper left side outside the SAA.Surgeons deemed intravascular intervention challenging and open splenectomy inevitable.Circulatory collapse occurred after anesthesia induction,likely due to a double rupture of the SAA.This double-rupture phenomenon may have resulted from an initial rupture of the SAA into the omental bursa,forming a hematoma that exerted a tamponade effect.A second rupture into the peritoneal cavity may have been triggered by decreased intra-abdominal pressure following anesthesia induction.The patient’s life was saved through early,coordinated,multidisciplinary significant postoperative bleeding or hypoxic encephalopathy.CONCLUSION Anesthesia-induced pressure reduction may trigger a second SAA rupture,causing collapse.Early diagnosis and multidisciplinary teamwork improve outcomes.This is a rare and life-threatening case of SAA rupture,which is of great significance to the medical community for understanding and handling such emergencies.展开更多
Mechanical properties of Mg-3Gd(wt.%)samples with average grain sizes ranging from 3 to 45μm were characterized by room temperature tensile test.A reversal of the trade-off,i.e.,high yield strength and large tensile ...Mechanical properties of Mg-3Gd(wt.%)samples with average grain sizes ranging from 3 to 45μm were characterized by room temperature tensile test.A reversal of the trade-off,i.e.,high yield strength and large tensile elongation,was simultaneously observed in the fine-grained samples.The microstructures and hardening response were analyzed in terms of the viewpoint of strain evolution,including local strain evolution by tensile digital image correlation strain measurement,and lattice strain by using synchrotronbased in-situ high energy X-ray diffraction technique.The dislocation-based deformation mechanisms were investigated to underpin the microstructural origin of the yield point phenomenon and enhancement in work-hardening.The occurrence of the yield point phenomenon represented by a yield drop and propagation of the Lüders band is related to the absence of mobile dislocations at an early stage and to the slip transmission between the adjacent grain.The extraordinary work-hardening enhancement over an extended range can be ascribed mainly to the increases in dislocation multiplication and accumulation capabilities by the activation and interaction of multiple slip systems includingand<c+a>types.These results contribute to the design of strong and ductile Mg alloys.展开更多
1|Goalie Phenomenon The goalie phenomenon describes a group of health issues that may become apparent in children who prefer playing as goalkeepers.This preference might not only be about the excitement of the role bu...1|Goalie Phenomenon The goalie phenomenon describes a group of health issues that may become apparent in children who prefer playing as goalkeepers.This preference might not only be about the excitement of the role but also as a coping mechanism for underlying health issues that make continuous running and high physical exertion challenging.The term highlights how certain positions in sports can sometimes obscure or reveal hidden health conditions,particularly among young athletes[1–3].To our knowledge,this is the first paper to formally introduce the term“Goalie phenomenon”in the literature exploring exerciseinduced asthma and sports role preferences in children.展开更多
Primary congenital lymphedema(PCL)is a rare lymphatic disorder that typically presents in early life and is usually managed conservatively.In severe neonatal cases,however,complications such as skin necrosis and coagu...Primary congenital lymphedema(PCL)is a rare lymphatic disorder that typically presents in early life and is usually managed conservatively.In severe neonatal cases,however,complications such as skin necrosis and coagulopathy can occur.We report the case of a term male infant with prenatally diagnosed vascular malformations who presented with progressive limb swelling,hemorrhagic skin necrosis,and systemic signs of infection.Laboratory findings revealed severe thrombocytopenia and coagulopathy,consistent with Kasabach-Merritt-like phenomenon.The patient underwent staged surgical management,including limb decompression and debridement,followed by negative pressure wound therapy(NPWT),application of an acellular dermal matrix(ADM),and full-thickness skin grafting.The combined use of ADM and NPWT promoted rapid granulation tissue formation and neovascularization,resulting in stable wound coverage and successful limb preservation.Follow-up at 12 months showed excellent graft take,improved limb function,and no recurrence of necrosis or infection.This case highlights the potential role of integrating NPWT and regenerative scaffolds in managing complex neonatal wounds associated with PCL and Kasabach-Merritt-like phenomenon.To our knowledge,this is the first report describing such an approach in a neonate,offering a viable limb-salvaging strategy in otherwise life-threatening presentations.展开更多
With the availability of high-performance computing technology and the development of advanced numerical simulation methods, Computational Fluid Dynamics (CFD) is becoming more and more practical and efficient in engi...With the availability of high-performance computing technology and the development of advanced numerical simulation methods, Computational Fluid Dynamics (CFD) is becoming more and more practical and efficient in engineering. As one of the high-precision representative algorithms, the high-order Discontinuous Galerkin Method (DGM) has not only attracted widespread attention from scholars in the CFD research community, but also received strong development. However, when DGM is extended to high-speed aerodynamic flow field calculations, non-physical numerical Gibbs oscillations near shock waves often significantly affect the numerical accuracy and even cause calculation failure. Data driven approaches based on machine learning techniques can be used to learn the characteristics of Gibbs noise, which motivates us to use it in high-speed DG applications. To achieve this goal, labeled data need to be generated in order to train the machine learning models. This paper proposes a new method for denoising modeling of Gibbs phenomenon using a machine learning technique, the zero-shot learning strategy, to eliminate acquiring large amounts of CFD data. The model adopts a graph convolutional network combined with graph attention mechanism to learn the denoising paradigm from synthetic Gibbs noise data and generalize to DGM numerical simulation data. Numerical simulation results show that the Gibbs denoising model proposed in this paper can suppress the numerical oscillation near shock waves in the high-order DGM. Our work automates the extension of DGM to high-speed aerodynamic flow field calculations with higher generalization and lower cost.展开更多
At the late stage of solidification with ultrasonic treatment (UST) in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification micro...At the late stage of solidification with ultrasonic treatment (UST) in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification microstructure were investigated in order to better study the mechanism of UST. It is considered that the overflowing phenomenon occurs due to the changes of vibration and flow in the remaining semisolid. Because the overflowed portion comes from the region with intense UST effect and vibrates with the probe during solidification, great modification of primary and euteetic Si (about 10 pm in length) and refinement of primary a(Al) (about 70 μm in size) are observed in this portion.展开更多
目的探讨盐酸贝尼地平联合替米沙坦治疗原发性高血压的临床疗效。方法选取首都医科大学附属北京潞河医院2024年2月至12月收治的原发性高血压患者100例,按随机数字表法分为对照组和观察组,各50例。两组患者均口服替米沙坦片,观察组患者...目的探讨盐酸贝尼地平联合替米沙坦治疗原发性高血压的临床疗效。方法选取首都医科大学附属北京潞河医院2024年2月至12月收治的原发性高血压患者100例,按随机数字表法分为对照组和观察组,各50例。两组患者均口服替米沙坦片,观察组患者加用盐酸贝尼地平片。两组均连续治疗8周。结果观察组总有效率为88.00%,显著高于对照组的56.00%(P<0.05)。两组患者治疗后的24 h平均收缩压(24 h SBP)、夜间睡眠SBP、晨峰血压、24 h平均舒张压(24 h DBP)、夜间睡眠DBP,血清内皮素、过氧化脂质、胱抑素C(CysC)、超敏C反应蛋白、白细胞介素(IL)1、IL-6水平均显著降低,一氧化氮(NO)、25-羟维生素D[25-(OH)D]水平均显著升高(P<0.05);且观察组上述指标均显著优于对照组(P<0.05)。观察组与对照组不良反应发生率相当(12.00%比8.00%,P>0.05)。结论盐酸贝尼地平联合替米沙坦治疗原发性高血压,可有效降低血压,改善患者血压晨峰现象及血管内皮功能,降低CysC及25-(OH)D水平,并抑制炎性反应。展开更多
近年来随着手机薄型化趋势的发展以及对可靠性要求的提高,OLED(Organic Light-Emitting Diode)屏幕孔区出现彩虹纹现象的比例有一定的上升。本文定性、定量地分析了OLED屏幕孔区出现彩虹纹现象的原因,并基于此,建立了一套相对完备的可...近年来随着手机薄型化趋势的发展以及对可靠性要求的提高,OLED(Organic Light-Emitting Diode)屏幕孔区出现彩虹纹现象的比例有一定的上升。本文定性、定量地分析了OLED屏幕孔区出现彩虹纹现象的原因,并基于此,建立了一套相对完备的可以相互交叉印证结果的多维度分析测试方法。对薄膜封装(Thin Film Encapsulation,TFE)膜层结构成分的进一步优化,可以最大限度地降低可靠性测试后出现与孔区彩虹纹相关的暗斑风险。通过裂片,分析了高温高湿实验条件下孔区发生彩虹纹的区域和位置;并以透射电子显微镜(Transmission Electron Microscope,TEM)、飞行时间二次离子质谱(Time of Flight Secondary Ion Mass Spectrometry,TOF-SIMS)和X射线光电子能谱(X-ray Photoelectron Spectroscopy,XPS)系统分析了孔区产生现象的原因。实验结果表明,CVD1(Chemical Vapor Deposition 1)中SiON在高温高湿条件下,会逐步向SiO膜层转化。TEM和TOF-SIMS的结果表明,被氧化后膜层的含氮量小于2%;XPS分峰结果显示,CVD1-2表面的SiON几乎全部转化为SiO膜层。通过将TFE中CVD1-1的SiON膜层折光率从1.72提升为1.76,CVD1-1的SiON膜层被氧化的深度下降了70%。该分析方法的建立不仅解释了孔区CVD膜层被氧化后生成的SiO是造成出现彩虹纹现象的原因,而且提出了彩虹纹区域对OLED面板孔区可靠性的影响。该方案策略为OLED显示未来在车载、IT(Information Technology)、广告牌等具有更高可靠性要求领域的应用提供了相应的解决思路。展开更多
基金sponsored by the project No.50404001 from the National Natural Science Foundation of Chinathe National Key Fundamental Research & Development Project(Grant No.2007CB209601)+1 种基金the China National PetroleumCorporation Fundamental Research Program (Grant No.06A30102)the China Postdoctoral Science Foundation(Project No.2004035350)
文摘The electrophysical property of saturated rocks is very important for reservoir identification and evaluation. In this paper, the lattice Boltzmann method (LBM) was used to study the electrophysical property of rock saturated with fluid because of its advantages over conventional numerical approaches in handling complex pore geometry and boundary conditions. The digital core model was constructed through the accumulation of matrix grains based on their radius distribution obtained by the measurements of core samples. The flow of electrical current through the core model saturated with oil and water was simulated on the mesoscopic scale to reveal the non-Archie relationship between resistivity index and water saturation (I-Sw). The results from LBM simulation and laboratory measurements demonstrated that the I-Sw relation in the range of low water saturation was generally not a straight line in the log-log coordinates as described by the Archie equation. We thus developed a new equation based on numerical simulation and physical experiments. This new equation was used to fit the data from laboratory core measurements and previously published data. Determination of fluid saturation and reservoir evaluation could be significantly improved by using the new equation.
基金Supported by National High Level Hospital Clinical Research Funding,No.2022-PUMCH-B-119.
文摘BACKGROUND Splenic artery aneurysm(SAA)rupture is a rare,life-threatening condition characterized by acute intra-abdominal hemorrhage and hemodynamic instability.Ruptured SAAs may exhibit a biphasic and relatively slow clinical progression,commonly referred to as the“double-rupture phenomenon”.The reported incidence of the double-rupture phenomenon ranges 12%-21%in patients with ruptured SAAs,potentially due to variations in intra-abdominal pressure.Following anesthesia induction,muscle relaxation can decrease intra-abdominal pressure,potentially triggering the double-rupture phenomenon and leading to circulatory collapse.CASE SUMMARY A 61-year-old female presented to the Department of Emergency with upper abdominal pain,abdominal distension,dizziness,and vomiting.Her vital signs were initially stable.Physical examination revealed abdominal tenderness and positive-shifting dullness.Abdominal contrast-enhanced computed tomography revealed cirrhosis,severe portal hypertension,and splenomegaly.Acute rupture was suggested by a hematoma on the upper left side outside the SAA.Surgeons deemed intravascular intervention challenging and open splenectomy inevitable.Circulatory collapse occurred after anesthesia induction,likely due to a double rupture of the SAA.This double-rupture phenomenon may have resulted from an initial rupture of the SAA into the omental bursa,forming a hematoma that exerted a tamponade effect.A second rupture into the peritoneal cavity may have been triggered by decreased intra-abdominal pressure following anesthesia induction.The patient’s life was saved through early,coordinated,multidisciplinary significant postoperative bleeding or hypoxic encephalopathy.CONCLUSION Anesthesia-induced pressure reduction may trigger a second SAA rupture,causing collapse.Early diagnosis and multidisciplinary teamwork improve outcomes.This is a rare and life-threatening case of SAA rupture,which is of great significance to the medical community for understanding and handling such emergencies.
基金financially supported by the National Key Research and Develop-ment Program(No.2023YFB3712702)the National Natural Science Foundation of China(Nos.52071038,52071039,and 52301156)the Natural Science Foundation of Jiangsu Province(Nos.BK20232025 and BK20243005)。
文摘Mechanical properties of Mg-3Gd(wt.%)samples with average grain sizes ranging from 3 to 45μm were characterized by room temperature tensile test.A reversal of the trade-off,i.e.,high yield strength and large tensile elongation,was simultaneously observed in the fine-grained samples.The microstructures and hardening response were analyzed in terms of the viewpoint of strain evolution,including local strain evolution by tensile digital image correlation strain measurement,and lattice strain by using synchrotronbased in-situ high energy X-ray diffraction technique.The dislocation-based deformation mechanisms were investigated to underpin the microstructural origin of the yield point phenomenon and enhancement in work-hardening.The occurrence of the yield point phenomenon represented by a yield drop and propagation of the Lüders band is related to the absence of mobile dislocations at an early stage and to the slip transmission between the adjacent grain.The extraordinary work-hardening enhancement over an extended range can be ascribed mainly to the increases in dislocation multiplication and accumulation capabilities by the activation and interaction of multiple slip systems includingand<c+a>types.These results contribute to the design of strong and ductile Mg alloys.
文摘1|Goalie Phenomenon The goalie phenomenon describes a group of health issues that may become apparent in children who prefer playing as goalkeepers.This preference might not only be about the excitement of the role but also as a coping mechanism for underlying health issues that make continuous running and high physical exertion challenging.The term highlights how certain positions in sports can sometimes obscure or reveal hidden health conditions,particularly among young athletes[1–3].To our knowledge,this is the first paper to formally introduce the term“Goalie phenomenon”in the literature exploring exerciseinduced asthma and sports role preferences in children.
文摘Primary congenital lymphedema(PCL)is a rare lymphatic disorder that typically presents in early life and is usually managed conservatively.In severe neonatal cases,however,complications such as skin necrosis and coagulopathy can occur.We report the case of a term male infant with prenatally diagnosed vascular malformations who presented with progressive limb swelling,hemorrhagic skin necrosis,and systemic signs of infection.Laboratory findings revealed severe thrombocytopenia and coagulopathy,consistent with Kasabach-Merritt-like phenomenon.The patient underwent staged surgical management,including limb decompression and debridement,followed by negative pressure wound therapy(NPWT),application of an acellular dermal matrix(ADM),and full-thickness skin grafting.The combined use of ADM and NPWT promoted rapid granulation tissue formation and neovascularization,resulting in stable wound coverage and successful limb preservation.Follow-up at 12 months showed excellent graft take,improved limb function,and no recurrence of necrosis or infection.This case highlights the potential role of integrating NPWT and regenerative scaffolds in managing complex neonatal wounds associated with PCL and Kasabach-Merritt-like phenomenon.To our knowledge,this is the first report describing such an approach in a neonate,offering a viable limb-salvaging strategy in otherwise life-threatening presentations.
基金co-supported by the Aeronautical Science Foundation of China(Nos.2018ZA52002,2019ZA052011).
文摘With the availability of high-performance computing technology and the development of advanced numerical simulation methods, Computational Fluid Dynamics (CFD) is becoming more and more practical and efficient in engineering. As one of the high-precision representative algorithms, the high-order Discontinuous Galerkin Method (DGM) has not only attracted widespread attention from scholars in the CFD research community, but also received strong development. However, when DGM is extended to high-speed aerodynamic flow field calculations, non-physical numerical Gibbs oscillations near shock waves often significantly affect the numerical accuracy and even cause calculation failure. Data driven approaches based on machine learning techniques can be used to learn the characteristics of Gibbs noise, which motivates us to use it in high-speed DG applications. To achieve this goal, labeled data need to be generated in order to train the machine learning models. This paper proposes a new method for denoising modeling of Gibbs phenomenon using a machine learning technique, the zero-shot learning strategy, to eliminate acquiring large amounts of CFD data. The model adopts a graph convolutional network combined with graph attention mechanism to learn the denoising paradigm from synthetic Gibbs noise data and generalize to DGM numerical simulation data. Numerical simulation results show that the Gibbs denoising model proposed in this paper can suppress the numerical oscillation near shock waves in the high-order DGM. Our work automates the extension of DGM to high-speed aerodynamic flow field calculations with higher generalization and lower cost.
基金Project(50874022)supported by the National Natural Science Foundation of China
文摘At the late stage of solidification with ultrasonic treatment (UST) in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification microstructure were investigated in order to better study the mechanism of UST. It is considered that the overflowing phenomenon occurs due to the changes of vibration and flow in the remaining semisolid. Because the overflowed portion comes from the region with intense UST effect and vibrates with the probe during solidification, great modification of primary and euteetic Si (about 10 pm in length) and refinement of primary a(Al) (about 70 μm in size) are observed in this portion.
文摘目的探讨盐酸贝尼地平联合替米沙坦治疗原发性高血压的临床疗效。方法选取首都医科大学附属北京潞河医院2024年2月至12月收治的原发性高血压患者100例,按随机数字表法分为对照组和观察组,各50例。两组患者均口服替米沙坦片,观察组患者加用盐酸贝尼地平片。两组均连续治疗8周。结果观察组总有效率为88.00%,显著高于对照组的56.00%(P<0.05)。两组患者治疗后的24 h平均收缩压(24 h SBP)、夜间睡眠SBP、晨峰血压、24 h平均舒张压(24 h DBP)、夜间睡眠DBP,血清内皮素、过氧化脂质、胱抑素C(CysC)、超敏C反应蛋白、白细胞介素(IL)1、IL-6水平均显著降低,一氧化氮(NO)、25-羟维生素D[25-(OH)D]水平均显著升高(P<0.05);且观察组上述指标均显著优于对照组(P<0.05)。观察组与对照组不良反应发生率相当(12.00%比8.00%,P>0.05)。结论盐酸贝尼地平联合替米沙坦治疗原发性高血压,可有效降低血压,改善患者血压晨峰现象及血管内皮功能,降低CysC及25-(OH)D水平,并抑制炎性反应。
文摘近年来随着手机薄型化趋势的发展以及对可靠性要求的提高,OLED(Organic Light-Emitting Diode)屏幕孔区出现彩虹纹现象的比例有一定的上升。本文定性、定量地分析了OLED屏幕孔区出现彩虹纹现象的原因,并基于此,建立了一套相对完备的可以相互交叉印证结果的多维度分析测试方法。对薄膜封装(Thin Film Encapsulation,TFE)膜层结构成分的进一步优化,可以最大限度地降低可靠性测试后出现与孔区彩虹纹相关的暗斑风险。通过裂片,分析了高温高湿实验条件下孔区发生彩虹纹的区域和位置;并以透射电子显微镜(Transmission Electron Microscope,TEM)、飞行时间二次离子质谱(Time of Flight Secondary Ion Mass Spectrometry,TOF-SIMS)和X射线光电子能谱(X-ray Photoelectron Spectroscopy,XPS)系统分析了孔区产生现象的原因。实验结果表明,CVD1(Chemical Vapor Deposition 1)中SiON在高温高湿条件下,会逐步向SiO膜层转化。TEM和TOF-SIMS的结果表明,被氧化后膜层的含氮量小于2%;XPS分峰结果显示,CVD1-2表面的SiON几乎全部转化为SiO膜层。通过将TFE中CVD1-1的SiON膜层折光率从1.72提升为1.76,CVD1-1的SiON膜层被氧化的深度下降了70%。该分析方法的建立不仅解释了孔区CVD膜层被氧化后生成的SiO是造成出现彩虹纹现象的原因,而且提出了彩虹纹区域对OLED面板孔区可靠性的影响。该方案策略为OLED显示未来在车载、IT(Information Technology)、广告牌等具有更高可靠性要求领域的应用提供了相应的解决思路。