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Comparison of a Full Second-Order Moment Model and an Algebraic Stress Two-Phase Turbulence Model for Simulating Bubble-Liquid Flows in a Bubble Column

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Chinese journal of Chemical Engineering 2002年第2期10卷 142-148页

作者：周力行杨玟廉春英 L.S.Fan d.j.lee department of Engineering Mechanics Tsinghua University Beijing 100084 China department of Chemical Engineering The Ohio State University USA

A full second-order moment (FSM) model and an algebraic stress (ASM) two-phase turbulence modelare proposed and applied to predict turbulent bubble-liquid flows in a 2d rectangular bubble column. Predictiongives the bubble and liquid velocities, bubble volume fraction, bubble and liquid Reynolds stresses and bubble-liquidvelocity correlation. For predicted two-phase velocities and bubble volume fraction there is only slight differencebetween these two models, and the simulation results using both two models are in good agreement with the particleimage velocimetry (PIV) measurements. Although the predicted two-phase Reynolds stresses using the FSM are insomewhat better agreement with the PIV measurements than those predicted using the ASM, the Reynolds stressespredicted using both two models are in general agreement with the experiments. Therefore, it is suggested to usethe ASM two-phase turbulence model in engineering application for saving the computation time.

关键词： second-order moment model two-phase turbulence bubble-liquid flow bubble column

Microchimerism in recurrent miscarriage

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Cellular & Molecular Immunology 2014年第6期11卷 589-594页

作者： Hilary S Gammill Mary d Stephenson Tessa M Aydelotte j lee Nelson Clinical Research division Fred Hutchinson Cancer Research Center Seattle WA USA department of Obstetrics & Gynecology University of Washington Seattle WA USA department of Obstetrics and Gynecology University of Chicago Chicago IL USA and Department of Obstetrics and Gynecology University of Illinois at Chicago Chicago IL USA division of Rheumatolegy University of Washington Seattle WA USA

Maternal-fetal cell exchange during pregnancy results in acquisition of microchimerism, which can durably persist in both recipients. Naturally acquired microchimerism may impact maternal-fetal interaction in pregnancy. We conducted studies to ask whether microchimerism that a woman acquired from her own mother is detectable before or during pregnancy in women with recurrent miscarriage. Fetal microchimerism was also assayed. Women with primary idiopathic recurrent miscarriage （n=23） and controls （n=31） were studied. Genotyping was conducted for probands, their mothers and the fetus, a non-shared polymorphism identified and quantitative polymerase chain reaction performed to measure microchimerismin peripheral blood mononuclear cells. Preconception comparisons were made between recurrent miscarriage subjects and controls, using logistic regression and Wilcoxon rank sum. Longitudinal microchimerism in subsequent pregnancies of recurrent miscarriage subjects was described. There was a trend toward lower preconception detection of microchimerism in recurrent miscarriage versus controls, 6% vs. 19% （1/16 vs. 6/31, P=0.2）. during pregnancy, 3111 （27%） of recurrent miscarriage subjects who went on to have a birth had detection of microchimerism from their own mother, whereas neither of two subjects who went on to miscarry had detection （0/2）. This initial data suggest that microchimerism from a woman＇s own mother, while detectable in women with recurrent miscarriage, may differ from controls and according to subsequent pregnancy outcome. Further studies are needed to determine the cell types,quantities and any potential functional role of microchimerism in recurrent miscarriage.

关键词： microchimerism pregnancy recurrent miscarriage reproduction

Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

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Neural Regeneration Research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha j.Holdsworth Alistair j.Gunn Laura Bennet Hamid Abbasi Mātai Medical Research Institute Tairāwhiti GisborneNew Zealand department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand Center for Brain Research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

ZnO-Embedded Expanded Graphite Composite Anodes with Controlled Charge Storage Mechanism Enabling Operation of Lithium-Ion Batteries at Ultra-Low Temperatures

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Energy & Environmental Materials 2023年第4期6卷 31-39页

作者： Kun Ryu Michael j.lee Kyungbin lee Seung Woo lee George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

As lithium(Li)-ion batteries expand their applications,operating over a wide temperature range becomes increasingly ***,the lowtemperature performance of conventional graphite anodes is severely hampered by the poor diffusion kinetics of Li ions(Li^(+)).Here,zinc oxide(ZnO) nanoparticles are incorporated into the expanded graphite to improve Li^(+)diffusion kinetics,resulting in a significant improvement in lowtemperature *** ZnO-embedded expanded graphite anodes are investigated with different amounts of ZnO to establish the structurecharge storage mechanism-performance relationship with a focus on lowtemperature *** analysis reveals that the ZnOembedded expanded graphite anode with nano-sized ZnO maintains a large portion of the diffusion-controlled charge storage mechanism at an ultra-low temperature of-50℃ due to this significantly enhanced Li^(+)diffusion rate,a full cell with the ZnO-embedded expanded graphite anode and a LiNi_(0.88)Co_(0.09)Al_(0.03)O_(2)cathode delivers high capacities of 176 mAh g^(-1)at20℃ and 86 mAh g^(-1)at-50℃ at a high rate of 1 *** outstanding low-temperature performance of the composite anode by improving the Li^(+)diffusion kinetics provides important scientific insights into the fundamental design principles of anodes for low-temperature Li-ion battery operation.

关键词： diffusive and capacitive charge storages expanded graphite composites anode lithium-ion battery low-temperature operation transition metal oxide

Effects of Reduced Nocturnal Temperature on Performance and Behavior of Nursery Pigs

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journal of Integrative Agriculture 2012年第9期11卷 1509-1516页

作者： lee j johnston West Central Research and Outreach Center University of MinnesotaMorris MN 56267 USA

Previous studies suggested that pigs prefer lower environmental temperatures during nighttime compared to daytime. So reducing nocturnal temperature in nursery barns may not jeopardize performance or welfare of pigs, but can save energy for heating the barn. A study was conducted to investigate growth performance and behavioral response of nursery pigs to reduced nocturnal temperature. This study was conducted in four replicates, each utilizing 270 newly weaned pigs and lasting for 5 wk. Temperature setpoint in the control room （CON） was started at 30℃ and decreased by 2℃ per week. In the treatment room （RNT）, temperature setpoint was maintained same as in CON between 7：00 h and 19：00 h, and reduced by 8~C between 19：00 h and 7：00 h starting from d 5. Growth performance （15 pens/room, 9 pigs/pen, BW=（6.3±0.61） kg） was monitored for 5 wk, and behaviors in 6 pens in each room were video-recorded for 24 h 3 d after being exposed to the experimental temperature. Instantaneous scan sampling was performed to determine time budgets for standing, sitting, eating, drinking, belly nosing, three postures of lying, and huddling. Two focal pigs were continuously viewed to record duration and occurrence of eating and drinking. Reduced nocturnal temperature did not affect the growth performance of the pigs, time spent standing, sitting, total lying and eating or duration and frequencies of eating and drinking （all P〉0.10）. However, RNT increased time spent lying sternal （83 vs. 72%, P〈0.001） and number of pigs that were huddling （70 vs. 50% of lying pigs, P〈0.001）, and decreased time spent lying laterally （0.8 vs. 4.6%, P〈0.001）, lying half laterally （5.3 vs. 11.0%, P〈0.001）, and belly nosing （0.9 vs. 1.7%, P=0.01） during nighttime. These results indicate that nursery pigs adopted the posture of lying sternal and huddled together to reduce heat loss from their body surface to maintain thermal balance and growth performance in RNT. Such mild reduction in nocturnal temperature in th

关键词： reduced nocturnal temperature behavior growth performance pigs

Flexural-wave-generation using a phononic crystal with a piezoelectric defect

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Applied Mathematics and Mechanics(English Edition) 2023年第8期44卷 1241-1262页

作者： S.H.jO d.lee department of Mechanical Roboticsand Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea department of Mechanical Engineering Seoul National UniversitySeoul 08826Republic of Korea

This paper proposes a method to amplify the performance of a flexural-wave-generation system by utilizing the energy-localization characteristics of a phononic crystal(PnC)with a piezoelectric defect and an analytical approach that accelerates the predictions of such wave-generation *** proposed analytical model is based on the Euler-Bernoulli beam *** proposed analytical approach,inspired by the transfer matrix and S-parameter methods,is used to perform band-structure and time-harmonic analyses.A comparison of the results of the proposed approach with those of the finite element method validates the high predictive capability and time efficiency of the proposed model.A case study is explored;the results demonstrate an almost ten-fold amplification of the velocity amplitudes of flexural waves leaving at a defect-band frequency,compared with a system without the ***,design guidelines for piezoelectric-defect-introduced PnCs are provided by analyzing the changes in wave-generation performance that arise depending on the defect location.

关键词： phononic crystal(PnC) defect wave-generation fexural wave analytical model

Pan-TRK positive uterine sarcoma in immunohistochemistry without neurotrophic tyrosine receptor kinase gene fusions:A case report

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World journal of Clinical Cases 2025年第2期13卷 39-49页

作者： Seungmee lee Yu-Ra jeon Changmin Shin Sun-Young Kwon Sojin Shin department of Obstetrics and Gynecology Keimyung University School of MedicineDaegu 42601South Korea department of Pathology and Institute for Cancer Research Keimyung University School of MedicineDaegu 42601South Korea

BACKGROUNd The classification of uterine sarcomas is based on distinctive morphological and immunophenotypic characteristics,increasingly supported by molecular genetic *** on neurotrophic tyrosine receptor kinase(NTRK)gene fusionpositive uterine sarcoma,potentially aggressive and morphologically similar to fibrosarcoma,are limited due to its recent ***-TRK immunohistochemistry(IHC)analysis serves as an effective screening tool with high sensitivity and specificity for NTRK-fusion *** SUMMARY We report a case of a malignant mesenchymal tumor originating from the uterine cervix,which was pan-TRK IHC-positive but lacked NTRK gene fusions,accompanied by a brief literature review.A 55-year-old woman presented to the emergency department with abdominal pain and distension,exhibiting significant ascites and multiple solid pelvic *** examination revealed a tumor encompassing the uterine cervix,extending to the vagina and uterine corpus.A punch biopsy of the cervix indicated NTRK sarcoma with positive immunochemical pan-TRK ***,subsequent next generation sequencing revealed no NTRK gene fusion,leading to a diagnosis of poorly differentiated,advanced-stage *** The clinical significance of NTRK gene fusion lies in potential treatment with TRK inhibitors for positive *** such rare tumors is crucial due to the potential applicability of tropomyosin receptor kinase inhibitor treatment.

关键词： Uterine sarcoma Cervical sarcoma Neurotrophic tyrosine receptor kinase gene fusion Next generation sequencing Case report

Computational Analysis of a Variable Ejector Flow

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journal of Thermal Science 2006年第2期15卷 140-144页

作者： H.d. KIM j.H. lee T. SETOGUCHI S.MATSUO School of Mechanical Engineering Andong National University 388 Songchun-dong Andong 760-749 Korea department of Mechanical Engineering Saga University 1 Honjo Saga 840-8502 Japan

The present study addresses a variable ejector which can improve the ejector efficiency and control the re-circulation ratio under a fixed operating pressure ratio. The variable ejector is a facility to obtain specific recirculation ratio under a given operating pressure ratio by varying the ejector throat area ratio. The numerical simulations are carried out to provide an understanding of the flow characteristics inside the variable ejector. The sonic and supersonic nozzles are adopted as primary driving nozzles in the ejector system, and a movable cone cylinder, inserted into a conventional ejector-diffuser system, is used to change the ejector throat area ratio. The numerical simulations are based on a fully implicit finite volume scheme of the compressible, Reynolds-Averaged Navier-Stokes equations. The results show that the variable ejector can control the recirculation ratio at a fixed operating pressure ratio.

关键词： variable ejector ejector throat area ratio re-circulation ratio

Fabrication of ultrafine Nd-Fe-B powder by a modified reduction-diffusion process

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Rare Metals 2006年第Z2期25卷 223-226页

作者： jANG T.S. lee d.H. CHOI C.j. SEO W.S. lee Y.H. department of Electronic Materials Engineering Sunmoon University Korea Powder Materials Research Center Korea Institute of Machinery and Materials Korea Advanced Materials Analysis & Evaluation Center Korea Institute of Ceramic Engineering and Technology Korea

In order to obtain ultrafine Nd-Fe-B powder, a spray-dried precursor was treated by reduction-diffusion (R/d) process. And, unlike the conventional R/d process, calcium reduction that is a crucial step for the formation of Nd2Fe14B was performed without conglomerating the precursor with Ca powder. By adopting this modified process, it is possible to synthesize the hard magnetic Nd2Fe14B at the reaction temperature as low as 850 ℃. The average size of Nd2Fe14B particles that are uniformly distributed in the optimally treated powder was d2Fe14B particles were enclosed with thin layers of Nd-rich phase. Typical magnetic properties of such powder without eliminating impurity CaO were iHc=～5.9 kOe, Br=～5.5 kG, and (BH)max=～6 MGOe.

关键词： NdFeB powder spray drying reduction-diffusion process Nd2Fe14B magnetic powder