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Environmental Fate of Petroleum Hydrocarbons in Soil:Review of Multiphase Transport,Mass Transfer,and natural Attenuation Processes

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Pedosphere 2018年第6期28卷 833-847页

作者： Maria BALSEIRO-ROMERO Carmen MOnTERROSO juan j.CASARES Department of Chemical Engineering Centre for Research in Environmental Technologies (CRETUS)Universidade de Santiago de CompostelaSantiago de Compostela 15782(Spain) Department of Soil Science and Agricultural Chemistry Centre for Research in Environmental Technologies (CRETUS)Unzversidade de Santiago de CompostelaSantiago de Compostela 15782(Spain)

The increasing use of petroleum-derived fuels over the last few decades has subsequently augmented the risk of spills in the environment. Soil pollution with petroleum hydrocarbons(principally caused by leaks in pipelines and underground storage tanks) is one of the major sources of soil degradation. Once in soil, fuel hydrocarbons suffer from a wide variety of multiphase processes including transport(advection, diffusion, and dispersion) among and within phases(aqueous and non-aqueous liquid, gas, and soil solids), mass transfer among phases(volatilization, sorption, and solution), and other natural attenuation processes, such as biodegradation and plant uptake and metabolism. This review identifies and describes the major processes occurring in soil that have a significant influence on the environmental fate of petroleum hydrocarbons. The definition of the processes involved in pollutant migration and distribution in soil and the formulation of adequate equations using accurate parameters(e.g., diffusion coefficients, velocity of advective flows, and mass transfer coefficients) will allow prediction of the final fate of soil pollutants. In addition to transport and mass transfer processes,which are more widely studied, the incorporation of attenuation mechanisms driven by microorganisms and plants is essential to predict the final concentration of the pollutants in the whole multiphase scenario. This work underlines the importance of the determination of accurate parameters through the performance of laboratory and/or field-scale experiments to develop precise pollutant migration models.

关键词： degradation fuel-derived pollutants modelling multiphase non-aqueous phase liquid soil pollution soil processes sorption

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An Adaptive Lasso Grey Model for Regional FDI Statistics Prediction

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Computers, Materials & Continua 2021年第11期69卷 2111-2121页

作者： juan Huang Bifang Zhou Huajun Huang jianjiang Liu neal n.Xiong Centre for Innovation Research in Social Governance Changsha University of Science and TechnologyChangsha410114China College of Information Technology and Management Hunan University of Finance and EconomicsChangsha410205China Department of Mathematics and Computer Science Northeastern State UniversityTahlequah74464USA

To overcome the deficiency of traditional mathematical statistics methods,an adaptive Lasso grey model algorithm for regional FDI(foreign direct investment)prediction is proposed in this paper,and its validity is ***,the characteristics of the FDI data in six provinces of Central China are generalized,and the mixture model’s constituent variables of the Lasso grey problem as well as the grey model are ***,based on the influencing factors of regional FDI statistics(mean values of regional FDI and median values of regional FDI),an adaptive Lasso grey model algorithm for regional FDI was ***,an application test in Central China is taken as a case study to illustrate the feasibility of the adaptive Lasso grey model algorithm in regional FDI *** also select RMSE(root mean square error)and MAE(mean absolute error)to demonstrate the convergence and the validity of the ***,we train this proposedal gorithm according to the regional FDI statistical data in six provinces in Central China from 2006 to *** then use it to predict the regional FDI statistical data from 2019 to 2023 and show its changing *** extended work for the adaptive Lasso grey model algorithm and its procedure to other regional economic fields is also discussed.

关键词： Adaptive lasso grey model algorithm regional FDI statistics mean value of regional FDI median value of regional FDI

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海洋平台支撑板异种金属焊接试验研究

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精密成形工程 2024年第9期16卷 201-208页

作者：徐和林王江华廖娟西南交通大学希望学院成都610400 四川大学机械工程学院成都610065

目的结合Q245R/Q690D 2种材料的优势研究其焊接接头性能,获得最优的焊接和后热处理工艺参数。方法以某海洋平台建造为背景,选用E50-6焊丝、j形坡口设计对Q245R/Q690D中厚板多道次焊接进行试验研究。在8、12、16、20 kj/cm热输入下,对接... 详细信息

目的结合Q245R/Q690D 2种材料的优势研究其焊接接头性能,获得最优的焊接和后热处理工艺参数。方法以某海洋平台建造为背景,选用E50-6焊丝、j形坡口设计对Q245R/Q690D中厚板多道次焊接进行试验研究。在8、12、16、20 kj/cm热输入下,对接头进行力学性能测试和微观组织观察;为细化接头组织、提高综合力学性能,对最佳热输入下的接头进行不同温度的后热处理,后热处理温度分别为250、350、580℃并保温2 h,进一步观察接头的性能和微观组织。结果焊态下拉伸断裂均发生在Q245R母材侧,在12 kj/cm热输入下,焊缝表面硬度在338HV左右,焊缝冲击功为172 j;在20 kj/cm热输入下,冲击功下降至82.7 j,组织粗大且呈板条状。在250、350℃回火能够降低表面硬度,同时焊缝冲击功较焊态的略有上升,最大增加了21 j;在580℃回火后,内部晶粒粗大,焊缝表面硬度增大,最大为448HV,较焊态的提高了32.5%,同时冲击功显著下降,下降至80 j,下降约53.5%。结论Q245R/Q690D中厚板多道次焊接热输入采用12 kj/cm为宜,同时焊后对接头进行250~350℃回火并保温2 h为推荐后热处理方式。

关键词：异种金属焊接接头多道次焊接接头性能 Q245R/Q690D

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TWOPHASE FLOW OF HIGHLY COnCEnTRATED SLURRY In A PIPELInE

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journal of Hydrodynamics 2004年第3期16卷 325-331页

作者： nIFu-sheng ZHAOLi-juan MATOUSEKV. VLASBLOMW.j. ZWARTBOLA. FacultyofMechanicalandElectricalEngineering HohaiUniversityChangzhou213022China SectionofDredgingTechnology DelftUniversityofTechnologyTheNetherlands

Hydraulic transport of sand is one of the key processes in river, lake,harbor and waterway dredging engineering. Understanding the flow resistance, solid distribution,flow stratification, transport economy, etc. , in the two-phase flow of sand-water mixture through apipeline is crucial to the design and operation of power drives of a dredger, and to theconstruction of a dredging project. This paper presents the intensive laboratory experimental dataand physical and numerical analyses on the highly concentrated slurry flow under an extended largerange of slurry mean velocities for three narrow-graded sands of different sizes. The investigationindicates that the solids concentration and particle size strongly affect the slurry flowcharacteristics.

关键词： two-phase flow hydraulic transport laboratory experiment modeling

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退火温度对共挤压DP600/AA1060层合板微观组织及力学性能的影响

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锻压技术 2024年第5期49卷 219-225页

作者：江永涛彭凤英廖娟福州大学机械工程及自动化学院福建福州350116

以转角复合挤压工艺制备的DP600/AA1060(双相钢/铝)层合板为研究对象,探究不同退火温度(490、520和550℃)下层合板的界面力学性能及微观组织。通过界面剪切试验和显微硬度测试试验对界面结合处及两侧金属进行了力学性能研究,采用扫描电... 详细信息

以转角复合挤压工艺制备的DP600/AA1060(双相钢/铝)层合板为研究对象,探究不同退火温度(490、520和550℃)下层合板的界面力学性能及微观组织。通过界面剪切试验和显微硬度测试试验对界面结合处及两侧金属进行了力学性能研究,采用扫描电镜和能谱仪分析不同退火温度对层合板界面形貌变化和成分分布的影响。试验结果表明:退火处理有助于提高层合板结合区域的硬度。随着退火温度的升高,界面剪切强度增加,在550℃下界面剪切强度相比于未退火时提高了2.2倍。随着退火温度的升高,钢/铝复合界面开始出现间断的扩散层,界面主要失效形式由脆性断裂转变为韧性断裂,层合板的塑性变形能力得到了改善。

关键词： DP600/AA1060层合板转角复合挤压工艺退火温度显微硬度界面强度微观组织共挤压成形

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结构参数对金属丝网夹芯板力学性能的影响

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兵器材料科学与工程 2024年第2期47卷 29-35页

作者：郭晴晴钱金行廖娟福州大学机械工程及自动化学院福建福州350116

为了研究不锈钢编织金属丝网(SSWWM)芯构成的轻质夹芯板的性能,用真空钎焊技术制备不同结构参数(层数、金属网的堆叠顺序和中间层)的夹芯板。对金属丝网夹芯板进行拉伸试验和三点弯曲试验,评估其力学性能。并对抗弯刚度的理论解析值与... 详细信息

为了研究不锈钢编织金属丝网(SSWWM)芯构成的轻质夹芯板的性能,用真空钎焊技术制备不同结构参数(层数、金属网的堆叠顺序和中间层)的夹芯板。对金属丝网夹芯板进行拉伸试验和三点弯曲试验,评估其力学性能。并对抗弯刚度的理论解析值与试验值进行比较。结果表明:适当增加夹芯板的层数、合适的堆叠顺序、在金属丝网间加入层间板均可显著提升夹芯板的力学性能。在所有试样中,带层间板的三层混合堆叠夹芯板(Tw-mix)的抗弯刚度最佳,带层间板的双层45°(Dw-45°)夹芯板的抗拉强度和伸长率最高。

关键词：夹芯板力学性能金属丝网轻量化理论弯曲刚度

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Clinical and Demographic Profile of Women with Uterine Fibroids Living in Puerto Rico

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Open journal of Obstetrics and Gynecology 2024年第9期14卷 1347-1362页

作者： Edwin Y. Soto-Velázquez Alexander j. jaramillo-Cañas Shania n. Aponte-Paris Gabriela V. Martínez-Marrero Irazu S. Guinan Gabrielle A. Rivera-Maldonado Alexandra novas Pedro L. Cruz-Rosa Idhaliz Flores-Caldera Maricarmen Colón-Diaz Department of Physiology and Pathology San Juan Bautista School of Medicine Caguas Puerto Rico United States Ponce Research Institute Ponce Health Sciences University Ponce Puerto Rico United States

Introduction: Uterine leiomyomas, or fibroids, are prevalent benign tumors affecting up to 70% of reproductive-age women in the United States, significantly impacting productivity and quality of life. Despite their commonality, the epidemiology and clinical patterns of leiomyomas in Puerto Rico remain inadequately researched. Methods: This study conducted a secondary data analysis using clinical, menstrual cycle characteristics, and demographic data from self-administered questionnaires of women undergoing diagnostic laparoscopy for endometriosis in Puerto Rico. Chi-square tests and t-tests analyzed categorical and continuous variables, respectively (p Results: Among 1,610 endometriosis cases, 312 included uterine fibroids. Prevalence estimates were 10.3% (40 years). Primiparous women averaged 22.14 years, with 40.71% having 2 - 3 pregnancies and 26.28% experiencing miscarriages. Symptoms included infertility (29.5%), dyspareunia (40.7%), severe pain (50%), and dysmenorrhea (75.6%). Comorbidities included ovarian cysts (52.2%) and abnormal uterine bleeding (37.8%). Conclusions: Advanced age, parity, and comorbidities like diabetes and hypertension were prevalent in our cohort. Understanding the epidemiological profile of women living in Puerto Rico with uterine fibroids is crucial for improving diagnostic awareness and enhancing patient care.

关键词： Uterine Fibroids Puerto Rico Epidemiology Dysmenorrhea Abnormal Uterine Bleeding

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Multifaceted role of one-carbon metabolism on immunometabolic control and growth during pregnancy, lactation and the neonatal period in dairy cattle

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journal of Animal Science and Biotechnology 2021年第1期12卷 82-109页

作者： Danielle n.Coleman Abdulrahman S.Alharthi Yusheng Liang Matheus Gomes Lopes Vincenzo Lopreiato Mario Vailati-Riboni juan j.Loor Department of Animal Sciences Division of Nutritional SciencesUniversity of IllinoisUrbanaIL 61801USA .2Department of Animal Production College of Food and Agriculture SciencesKing Saud UniversityRiyadh 11451Saudi Arabia .3Department of Animal Sciences Food and NutritionFaculty of AgricultureFood and Environmental ScienceUniversitàCattolica del Sacro Cuore29122 PiacenzaItaly.

Dairy cattle undergo dramatic metabolic, endocrine, physiologic and immune changes during the peripartal period largely due to combined increases in energy requirements for fetal growth and development, milk production, and decreased dry matter intake. The negative nutrient balance that develops results in body fat mobilization,subsequently leading to triacylglycerol(TAG) accumulation in the liver along with reductions in liver function,immune dysfunction and a state of inflammation and oxidative stress. Mobilization of muscle and gluconeogenesis are also enhanced, while intake of vitamins and minerals is decreased, contributing to metabolic and immune dysfunction and oxidative stress. Enhancing post-ruminal supply of methyl donors is one approach that may improve immunometabolism and production synergistically in peripartal cows. At the cellular level, methyl donors(e.g. methionine, choline, betaine and folic acid) interact through one-carbon metabolism to modulate metabolism,immune responses and epigenetic events. By modulating those pathways, methyl donors may help increase the export of very low-density lipoproteins to reduce liver TAG and contribute to antioxidant synthesis to alleviate oxidative stress. Thus, altering one-carbon metabolism through methyl donor supplementation is a viable option to modulate immunometabolism during the peripartal period. This review explores available data on the regulation of one-carbon metabolism pathways in dairy cows in the context of enzyme regulation, cellular sensors and signaling mechanisms that might respond to increased dietary supply of specific methyl donors. Effects of methyl donors beyond the one-carbon metabolism pathways, including production performance, immune cell function,mechanistic target or rapamycin signaling, and fatty acid oxidation will also be highlighted. Furthermore, the effects of body condition and feeding system(total mixed ration vs. pasture) on one-carbon metabolism pathways are explored. Poten

关键词： Epigenetics Immune system Metabolism Methyl donor Transition period

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Effect of tibolone pretreatment on kinases and phosphatases that regulate the expression and phosphorylation of Tau in the hippocampus of rats exposed to ozone

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neural Regeneration Research 2018年第3期13卷 440-448页

作者： Rodolfo Pinto-Almazán julia j. Segura-Uribe Marvin A. Soriano-Ursúa Eunice D. Farfán-García juan M. Gallardo Christian Guerra-Araiza Unidad de Investigación Hospital Regional de Alta Especialidad Ixtapaluca Carretera Federal México-Puebla km 34.5 C.P. 56530. Ixtapaluca State of Mexico Mexico Institute for the Developing Mind Children's Hospital Los Angeles Los Angeles CA USA Department of Pediatrics Keck School of Medicine University of Southern California Los Angeles CA USA Unidad de Investigación Médica en Enfermedades neurológicas Hospital de Especialidades Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Av. Cuauhtémoc 330 Col. Doctores. C. P. 06720. Mexico City Mexico Escuela Superior de Medicina Instituto Politécnico Nacional Plan de San Luis y Diaz Mirón Col. Casco de Santo Tomis. C. P. 11340. Mexico City Mexico Unidad de Investigación Médica en Enfermedades nefrológicas Hospital de Especialidades Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Av. Cuauhtémoc 330 Col. Doctores. C. P. 06720. Mexico City Mexico Unidad de Investigación Médica en Farmacologia Hospital de Especialidades Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Av. Cuauhtémoc 330 Col. Doctores. C. P. 06720. Mexico City Mexico

Oxidative stress （OS） is a key process in the development of many neurodegenerative diseases, memory disorders, and other pathological processes related to aging. Tibolone （TIB）, a synthetic hormone used as a treatment for menopausal ymptoms, decreases lipoperoxidation levels, prevents memory impairment and learning disability caused by ozone （O3） exposure. However, it is not clear if TIB could prevent the increase in phosphorylation induced by oxidative stress of the microtubule-associated protein Tau. In this study, the effects of TIB at different times of administration on the phosphorylation of Tau, the activation of glycogen synthase kinase-3β （GSK3β）, and the inactivation of Akt and phosphatases PP2A and PTEn induced by O3 exposure were assessed in adult male Wistar rats. Rats were divided into 10 groups： control group （ozone-free air plus vehicle [C]）, control ＋ TIB group （ozone-free air plus TIB 1 mg/kg [C ＋ TIB]）; 7,15, 30, and 60 days of ozone exposure groups [O3] and 7, 15, 30, and 60 days of TIB 1 mg/kg before ozone exposure groups [O3 ＋ TIB]. The effects of O3 exposure and TIB administration were assessed by western blot analysis of total and phosphorylated Tau, GSK3β, Akt, PP2A, and PTEn proteins and oxidative stress marker nitrotyrosine, and superoxide dismutase activity and lipid peroxidation of malondialdehyde by two different spectrophotometric methods （Marklund and TBARS, respectively）. We observed that O3 exposure increases Tau phosphorylation, which is correlated with decreased PP2A and PTEn protein levels, diminished Akt protein levels, and increased GSK3β protein levels in the hippocampus of adult male rats. The effects of O3 exposure were prevented by the long-term treatment （over 15 days） with TIB. Malondialdehyde and nitrotyrosine levels increased from 15 to 60 days of exposure to O3 in comparison to C group, and superoxide dismutase activity decreased. Furthermore, TIB administration limited the changes induced by O3 exposure. Our results

关键词： tibolone oxidative stress ozone exposure Tau GSK3 hippocampus neuroprotection

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Analysis of alkaline phosphatase and γ-glutamyltransferase after radiofrequency ablation of primary liver cancer: A retrospective study

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World journal of Gastrointestinal Surgery 2024年第9期16卷 2860-2869页

作者： Wen-Yu Huang Sheng Zheng Dan Zhu Ying-Lang Zeng juan Yang Xue-Li Zeng Pei Liu Shun-Ling Zhang Ming Yuan Zhi-Xia Wang Department of Tumor and Vascular Interventional Therapy Xiamen Humanity HospitalXiamen 361000Fujian ProvinceChina Department of Gastroenterology The Third People's Hospital of Yunnan ProvinceKunming 650011Yunnan ProvinceChina Medical Imaging Center Qian Wei Hospital of Jilin ProvinceChangchun 130000Jilin ProvinceChina Department of Science and Education The Third People's Hospital of Yunnan ProvinceKunming 650011Yunnan ProvinceChina Graduate School of Clinical Medicine Dali UniversityDali 671000Yunnan ProvinceChina Department of Hepatobiliary Surgery Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina Department of Oncology The Affiliated Shuyang Hospital of Xuzhou Medical UniversitySuqian 223600Jiangsu ProvinceChina

BACKGROUnD Changes in alkaline phosphatase(ALP)andγ-glutamyltransferase(GGT)levels in patients with primary liver cancer(PLC)after radiofrequency ablation(RFA).Hepatocellular carcinoma is a malignant tumor with high incidence *** a common local treatment,RFA has attracted much attention for its efficacy and influence on liver *** To investigate the effect of serum ALP and GGT levels on the prognosis of patients with PLC treated by *** The preoperative clinical data of 165 patients who were pathologically or clinically diagnosed with PLC and who received RFA in our hospital between October 2018 and june 2023 were *** chi-square test was used to compare the data between *** Kaplan-Meier method and Cox regression were used to analyze the associ-ations between serum ALP and GGT levels and overall survival,progression-free survival(PFS)and clinical characteristics of patients before *** The 1-year survival rates of patients with normal(≤135 U/L)and abnormal(>135 U/L)serum ALP before treatment were 91%and 79%,respectively;the 2-year survival rates were 90%and 68%,respectively;and the 5-year survival rates were 35%and 18%,*** difference between the two groups was statistically significant(P=0.01).Before treatment,the 1-year survival rates of patients with normal serum GGT levels(≤45 U/L)and abnormal serum GGT levels(>45 U/L)were 95%and 87%,the 2-year survival rates were 85%and 71%,and the 5-year survival rates were 37%and 21%,*** difference between the two groups was statist-ically significant(Pnfidence interval(95%CI):1.068-2.921,P=0.027]and GGT(HR=2.312,95%CI:1.367-3.912,P=0.002)is closely related to the overall survival of PLC patients after RF ablation and is an independent prognostic *** 1-year PFS rates were 72%and 50%,the 2-year PFS rates were 52%and 21%,and the 5-year PFS rates were 14%and 3%,*** difference between the

关键词： Alkaline phosphatase γ-glutamyltransferase Radiofrequency ablation Primary liver cancer Retrospective study

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