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Linking temporal records

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Frontiers of Computer Science 2012年第3期6卷 293-312页

作者： Pei LI Xin luna DONG Andrea MAURINO Divesh SRIVASTAVA Department of Informatics Systems and Communication University of Milan-Bicocca Milan 20126 Italy Data Management Department AT&T Labs-Research Florham Park NJ 07932 USA

Many data sets contain temporal records which span a long period of time; each record is associated with a time stamp and describes some aspects of a real-world en- tity at a particular time （e.g., author information in DBLP）. In such cases, we often wish to identify records that describe the same entity over time and so be able to perform interest- ing longitudinal data analysis. However, existing record link- age techniques ignore temporal information and fall short for temporal data. This article studies linking temporal records. First, we ap- ply time decay to capture the effect of elapsed time on entity value evolution. Second, instead of comparing each pair of records locally, we propose clustering methods that consider the time order of the records and make global decisions. Ex- perimental results show that our algorithms significantly out- perform traditional linkage methods on various temporal data sets.

关键词： temporal data record linkage data integration

Flow and thermal modeling of liquid metal in expanded microchannel heat sink

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Frontiers in Energy 2023年第6期17卷 796-810页

作者： Mingkuan ZHANG Xudong ZHANG luna GUO Xuan LI Wei RAO Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin 300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of TechnologyTianjin 300384China Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China School of Mechanical Engineering Tianjin University of CommerceTianjin 300134China Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China Beijing Key Laboratory of CryoBiomedical Engineering and Key Laboratory of Cryogenics Beijing 100190China

Liquid metal-based microchannel heat sinks (MCHSs) suffer from the low heat capacity of coolant, resulting in an excessive temperature rise of coolant and heat sink when dealing with high-power heat dissipation. In this paper, it was found that expanded space at the top of fins could distribute the heat inside microchannels, reducing the temperature rise of coolant and heat sink. The orthogonal experiments revealed that expanding the top space of channels yielded similar temperature reductions to changing the channel width. The flow and thermal modeling of expanded microchannel heat sink (E-MCHS) were analyzed by both using the 3-dimensional (3D) numerical simulation and the 1-dimensional (1D) thermal resistance model. The fin efficiency of E-MCHS was derived to improve the accuracy of the 1D thermal resistance model. The heat conduction of liquid metal in Z direction and the heat convection between the top surface of fins and the liquid metal could reduce the total thermal resistance (Rt). The above process was effective for microchannels with low channel aspect ratio, low mean velocity (Um) or long heat sink length. The maximum thermal resistance reduction in the example of this paper reached 36.0%. The expanded space endowed the heat sink with lower pressure, which might further reduce the pumping power (P). This rule was feasible both when fins were truncated (h_(2) 0).

关键词： liquid metal cooling heat sink expanded microchannel flow and thermal modeling

Proteomic analysis reveals dysregulated cell sign aling in ejaculated spermatozoa from in fertile men

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Asian Journal of Andrology 2019年第2期21卷 121-130页

作者： luna Samanta Rakesh Sharma Zhihong Cui Ashok Agarwal American Center for Reproductive Medicine Cleveland ClinicClevelandOH 44195USA Department of Zoology School of Life SciencesRavenshaw UniversityCuttackOdisha 753003India Institute of Toxicology The Third Military Medical UniversityChongqing 400038China

Dysfunctional sperm maturation is the primary reason for the poor sperm motility and morphology in infertile *** from infertile men were fractioned on three-layer density gradient(80%,60%,and 40%).Fraction 1(Fl)refers to the least mature stage having the lowest den sity,whereas the fraction 4(F4)in eludes the most dense and morphologically mature motile *** 2(F2)and fraction 3(F3)represent the intermediate *** were extracted and separated by dimensional *** were digested with trypsin and analyzed on a LTQ-Orbitrap Elite hybrid mass spectrometer *** annotations of proteins were obtained using bioinformatics tools and pathway databases.A total of 1585 proteins were detected in the four fractions of spermatozoa.A dysregulated protein turnover and protein folding may lead to accumulation of defective proteins or proteins that otherwise would have been eliminated during the process of maturation,resulting in the impairment of sperm fun *** nt chaper one expressi on may be a major con tributing factor to the defective sperm *** n receptor was predicted as a transcription regulator in one of the networks and the affected pathways were chaperone-mediated stress response,proteosomal pathway,and sperm *** down regulation of key pathways and protei ns which compromises the fertilizi ng potential of spermatozoa may provide in sight into the mecha nisms that lead to male infertility.

关键词： androgen receptor chaperone immature sperm infertile men proteasome spermatozoa

Identification and Characterization of Sulfur Compounds in Straight-Run Diesel Using Comprehensive Two-Dimensional GC Coupled with TOF MS

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China Petroleum Processing & Petrochemical Technology 2014年第3期16卷 10-18页

作者： Niu luna Liu Zelong Tian Songbai Research Institute of Petroleum Processing SINOPEC

The solid-phase extraction using Pd-Al2O3 as the stationary phase was employed to pre-separate the sulfur compounds in straight-run diesel. The isolating effect was evaluated quantitatively by gas chromatography with a sulfur chemiluminescence detector to harvest a satisfactory result. The identification of the structure of sulfur compounds by comprehensive two-dimensional gas chromatography coupled with the time-of-flight mass spectrometry indicated that cyclo-sulfides, benzothiophenes, dibenzothiophenes, dihydro-benzothiophenes and tetrahydro-dibenzothiophenes were included in straightrun diesel obtained from the Arab medium crude(AM). A total of 259 individual compounds were detected and their molecular structures were identified. The analytical method was approved as an effective way to characterize the composition of sulfur compounds, which reduced the interference of other compounds, facilitated the data presentation and provided more detailed information about molecular composition of sulfur compounds.

关键词： sulfur compounds straight-run diesel solid-phase extraction (SPE) comprehensive two-dimensional gas chromatographycoupled with the time-of-flight mass spectrometry (GC×GC-TOF MS)

PRSS1 and SPINK1 mutations in idiopathic chronic and recurrent acute pancreatitis

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World Journal of Gastroenterology 2014年第33期20卷 11788-11792页

作者： Mario Pelaez-luna Guillermo Robles-Diaz Samuel Canizales-Quinteros Maria T Tusié-luna Research Division School of Medicine UNAM Pancreas Clinic-Gastroenterology Department Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán Mexico City CP 14000 Mexico Maria T Tusié-luna Unit of Molecular Biology and Genomic Medicine Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán Mexico City CP 14000 Mexico

AIM: To identify gene mutations in PRSS1 and SPINK1 in individuals with early onset idiopathic chronic or recurrent acute pancreatitis.

关键词： Cationic trypsinogen SPINK1 PRSS1 Chronic pancreatitis Recurrent acute pancreatitis He-reditary pancreatitis

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响应面优化酶法提取地皮菜粗多糖工艺的研究

中国食品添加剂 2024年第10期35卷 118-124页

作者：张占霞闫路娜崔媛婕河北科技大学食品与生物学院石家庄050018

以野生地皮菜为原料,研究木瓜蛋白酶提取地皮菜粗多糖的最佳工艺。以多糖提取率为考察指标,首先对酶添加量、酶解时间、酶解温度和料液比四个提取条件进行单因素优化,并在单因素的基础上,进行响应面优化。结果表明:通过单因素试验优化,... 详细信息

以野生地皮菜为原料,研究木瓜蛋白酶提取地皮菜粗多糖的最佳工艺。以多糖提取率为考察指标,首先对酶添加量、酶解时间、酶解温度和料液比四个提取条件进行单因素优化,并在单因素的基础上,进行响应面优化。结果表明:通过单因素试验优化,酶添加量为4.00%、酶解温度60℃、酶解时间4 h和料液比为1∶50 g/mL。通过响应面试验优化,影响地皮菜多糖提取率的四个因素从大到小依次为:酶解时间>酶解温度>料液比>酶添加量;当酶添加量为4.00%、酶解时间为5 h、酶解温度为53.58℃和料液比为1∶45.11 g/mL时,地皮菜多糖提取率理论最高值为24.26%;实际测得多糖的平均提取率为24.69%,与模型预测值相近,可用于酶法提取地皮菜粗多糖。

关键词：地皮菜多糖木瓜蛋白酶响应面工艺优化

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Computational screening of transition metal-doped CdS for photocatalytic hydrogen production

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npj Computational Materials 2022年第1期8卷 2190-2198页

作者： Yuting Li Daniel Bahamon Mutasem Sinnokrot Lourdes F.vega Research and Innovation Center on CO_(2) and Hydrogen(RICH) Khalifa UniversityPO Box 127788Abu DhabiUAE Chemical Engineering Department.Khalifa University PO Box 127788Abu DhabiUAE Chemistry Department Khalifa UniversityPO Box 127788Abu DhabiUAE

A novel computational screening study of single transition metal(TM),TM-doped,and dual TMs-doped on CdS(110)surfaces via DFT calculations is presented,focusing on their stability and catalytic activity,searching for efficient photocatalysts for hydrogen *** based on key performance descriptors allowed to fine-tune the *** indicate that TM dopants can reduce the energy band gap and enhance impurity ***,Rh,and Pd were found to be the best dopants in TM-doped CdS,since their|ΔG_(H)|is 80%smaller compared to the pristine CdS ***,TM1-TM2-co-doped CdS catalysts show better performance for the hydrogen evolution reaction(HER)due to synergistic effects of the two TMs,where Co-Pt,Pd-Pt and Co-Rh co-doping CdS significantly reduced|ΔGH|to less than 0.1 *** point out four promising novel co-catalysts(i.e.,Co,Co-Pt,Co-Rh,Rh-Ag)with very good performance in HER,to be further explored in experimental studies.

关键词： surface transition allowed

Synthetic Time Series Generation Model for Analysis of Power System Operation and Expansion with High Renewable Energy Penetration

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Journal of Modern Power Systems and Clean Energy 2021年第4期9卷 849-858页

作者： Rodrigo Palma-Behnke Jorge vega-Herrera Felipe Valencia Oscar Nunez-Mata Energy Center Department of Electrical EngineeringFaculty of Mathematical and Physical SciencesUniversity of ChileSantiagoChile Department of Electrical Engineering University of AntofagastaAntofagastaChile School of Electrical Engineering University of Costa RicaSan PedroCosta Rica

The increasing integration of renewable energy sources into current power systems has posed the challenge of adequately representing the statistical properties associated with their variable power generation. In this paper, a novel procedure is proposed to select a proper synthetic time series generation model for renewable energy sources to analyze power system problems. The procedure takes advantage of the objective of the specific analysis to be performed and the statistical characteristics of the available time series. The aim is to determine the suitable model to be used for generating synthetic time series of renewable energy sources. A set of indicators is proposed to verify that the statistical properties of synthetic time series fit the statistical properties of the original data. The proposal can be integrated into systematic tools available for data analysis without compromising the representation of the statistical properties of the original time series. The procedure is tested using real data from the New Zealand power system in a mid-term analysis on integrating wind power plants into the power system. The results show that the proposed procedure reduces the error obtained in analyzing power systems compared with reference models.

关键词： Time series analysis renewable energy source solar energy stochastic process statistical analysis wind energy

Comparison of reflux esophagitis and its complications between African Americans and non-Hispanic whites

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World Journal of Gastroenterology 2009年第23期15卷 2878-2881页

作者： Kenneth J vega Sian Chisholm M Mazen Jamal Divisions of Gastroenterology and General Internal Medicine University of Florida Health Sciences Center Jacksonville Florida 32207 United States Gastroenterology Section Veterans Affairs Medical Center 5901 E. 7th St. Long Beach CA 90822 United States

AIM: To determine the effect of ethnicity on the severity of reflux esophagitis (RE) and its complications. METHODS: A retrospective search of the endoscopy database at the University of Florida Health Science Center/Jacksonville for all cases of reflux esophagitis and its complications from January 1 to March 31, 2001 was performed. Inclusion criteria were endoscopic evidence of esophagitis using the LA classif ication, reflux related complications and self-reported ethnicity. The data obtained included esophagitis grade, presence of a hiatal hernia, esophageal ulcer, stricture and Barrett's esophagus, and endoscopy indication. RESULTS: The search identified 259 patients with RE or its complications, of which 171 were non-Hispanic whites and 88 were African Americans. The mean ages and male/female ratios were similar in the two groups. RE grade, esophageal ulcer, stricture and hiatal hernia frequency were likewise similar in the groups. Barrett's esophagus was present more often in non-Hispanic whites than in African Americans (15.8% vs 4.5%; P < 0.01). Heartburn was a more frequent indication for endoscopy in non-Hispanic whites with erosive esophagitis than in African Americans (28.1% vs 7.9%; P < 0.001). CONCLUSION: Distribution of RE grade and frequency of reflux-related esophageal ulcer, stricture andhiatal hernia are similar in non-Hispanic whites and African Americans. Heartburn was more frequently and nausea/vomiting less frequently reported as the primary endoscopic indication in non-Hispanic whites compared with African Americans with erosive esophagitis or its complications. African Americans have a decreased prevalence of Barrett's esophagus compared with non-Hispanic whites.

关键词： Reflux esophagitis African American Hiatal hernia Barrett's esophagus