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High Temperature Iron Ethylene Polymerization Catalysts Bearing n,n,n'-2-(1-(2,4-Dibenzhydryl-6-fluorophenylimino)ethyl)-6-(1-(arylphenylimino)ethyl)pyridines

第五届国际高分子化学学术讨论会

作者： gregory n.tew Polymer Science and Engineering University of MassachusettsAmherstDepartment 120 Governors Dr AmherstMAUSA 01003

＜正＞Our primary research aim is to create new materials using a combination of principles,many of which are inspired by biology.1-10 We target supramolecular chemistry to organize molecules into novel materials.We

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Chinese Journal of Polymer Science 2024年第2期42卷 188-201,I0007页

作者： Chantsalnyam Bariashir Qiu-Yue Zhang Bayasgalan Ulambayar gregory A.Solan Tong-Ling Liang Wen-Hua Sun Institute of Chemistry and Chemical Technology Mongolian Academy of SciencesUlaanbaatar13330Mongolia Key Laboratory of Engineering Plastics and Beijing national Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China Department of Chemistry University of LeicesterUniversity RoadLeicesterLE17RHUK State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

The n,n,n'-ferrous chloride complexes,[2-{CMen(2,4-(CHPh)_(2)-6-FC_(6)H_(2))}-6-(CMenAr)C_(5)H_(3)n]FeCl_(2)(Ar=2,6-Me_(2)C_(6)H_(3) Fe1,2,6-Et_(2)C_(6)H_(3)Fe2,2,6-^(i)Pr_(2)C_(6)H_(3) Fe3,2,4,6-Me_(3)C_(6)H_(2) Fe4 and 2,6-Et_(2)-4-MeC_(6)H_(2) Fe5),each possessing one n-2,4-dibenzhydryl-6-fluorophenyl group,were readily synthesized from their respective unsymmetrical bis(imino)pyridines,L1-L5.Structural identification of Fe2 highlighted the variation in the steric properties provided by the dissimilar n-aryl groups.Following pre-treatment with either MAO or MMAO,complexes Fe1-Fe5 all displayed,at an operating temperature of 80℃,high activities for ethylene polymerization with levels falling in the order:Fe4> Fe1> Fe5> Fe2> Fe3.notably,Fe4/MAO displayed the highest activity of 1.94×10^(7) g_(PE)·mol_(Fe)^(-1)·h^(-1) of the study with only a modest loss in performance at 90℃.Generally,the resulting polyethylenes were highly linear(T_(m) range:122-132℃),narrowly disperse and of low molecular weight(M_(w) range:6.73-46.04kg·mol^(-1)),with the most sterically hindered Fe3 forming the highest molecular weight polymer of the series.End-group analysis by ^(1)H-and ^(13)CnMR spectroscopy revealed saturated alkyl(n-propyl and i-propyl) and unsaturated vinyl chain ends indicative of the role of both β-H elimination and chain transfer to aluminum as termination pathways.By comparison with previou sly reported iron precatalysts with similar tridentate ligand skeletons,it is evident that the introduction of a large benzhydryl group in combination with a fluorine as the ortho-substituents of one n-aryl group has the effect of enhancing thermal stability of the iron polymerization catalyst whilst maintaining appreciable polymer molecular weight.

关键词： Iron catalyst Ethylene polymerization Linear polyethylene Fluoride effect Thermal stability

Applying Earth Observation Technologies to Economic Consequence Modeling:A Case Study of COVID‑19 in Los Angeles County,California

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International Journal of Disaster Risk Science 2024年第1期15卷 18-31页

作者： Fynnwin Prager Marina T.Mendoza Charles K.Huyck Adam Rose Paul Amyx gregory Yetman Kristy F.Tiampo California State University Dominguez HillsCarsonCA 90747USA ImageCat Inc.Long BeachCA 90802USA University of Southern California Los AngelesCA 90015USA CIESIn–Center for International Earth Science Information network Columbia UniversityPalisadesNY 10964USA Cooperative Institute for Research in Environmental Sciences(CIRES) University of Colorado BoulderBoulderCO 80309USA

Earth observation(EO) technologies,such as very high-resolution optical satellite data available from Maxar,can enhance economic consequence modeling of disasters by capturing the fine-grained and real-time behavioral responses of businesses and the public.We investigated this unique approach to economic consequence modeling to determine whether crowd-sourced interpretations of EO data can be used to illuminate key economic behavioral responses that could be used for computable general equilibrium modeling of supply chain repercussions and resilience effects.We applied our methodology to the COVID-19 pandemic experience in Los Angeles County,California as a case study.We also proposed a dynamic adjustment approach to account for the changing character of EO through longer-term disasters in the economic modeling context.We found that despite limitations,EO data can increase sectoral and temporal resolution,which leads to significant differences from other data sources in terms of direct and total impact results.The findings from this analytical approach have important implications for economic consequence modeling of disasters,as well as providing useful information to policymakers and emergency managers,whose goal is to reduce disaster costs and to improve economic resilience.

关键词： Computable general equilibrium models COVID-19 Disaster economic impacts Earth observation Economic consequence analysis Los Angeles County

Comparison between upfront surgery and neoadjuvant chemotherapy in patients with locally advanced gastric cancer:A systematic review

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世界胃肠外科杂志:英文版(电子版) 2023年第8期15卷 1808-1818页

作者： Stylianos Fiflis Menelaos Papakonstantinou Alexandros Giakoustidis gregory Christodoulidis Eleni Louri Vasileios n Papadopoulos Dimitrios Giakoustidis A’Department of Surgery General Hospital PapageorgiouThessaloniki 56429Greece Department of General Surgery University Hospital of LarissaLarissa 41110Greece

BACKGROUnD Gastric cancer(GC)is a major health concern worldwide.Surgical resection and chemotherapy is the mainstay treatment for gastric carcinoma,however,the optimal approach remains unclear and should be different in each individual.Chemotherapy can be administered both pre-and postoperatively,but a multidisciplinary approach is preferred when possible.This is particularly relevant for locally advanced GC(LAGC),as neoadjuvant chemotherapy(nAT)could potentially lead to tumor downsizing thus allowing for a complete resection with curative intent.Even though the recent progress has been impressive,European and International guidelines are still controversial,thus attenuating the need for a more standardized approach in the management of locally advanced cancer.AIM To investigate the effects of nAT on the overall survival(OS),the disease-free survival(DFS),the morbidity and the mortality of patients with LAGC in comparison to upfront surgery(US).METHODS For this systematic review,a literature search was conducted between november and February 2023 in PubMed,Cochrane Library and clinicaltrials.gov for studies including patients with LAGC.Two independent reviewers conducted the research and extracted the data according to predetermined inclusion and exclusion criteria.The Preferred Reporting Items for Systematic Reviews and Meta-Analyses was used to form the search strategy and the study protocol has been registered in the International Prospective Register of Systematic Reviews.RESULTS Eighteen studies with 4839 patients with LAGC in total were included in our systematic review.Patients were separated into two groups;one receiving nAT before the gastrectomy(nAT group)and the other undergoing upfront surgery(US group).The OS ranged from 41.6%to 74.2%in the nAT group and from 30.9%to 74%in the US group.The DFS was also longer in the nAT group and reached up to 80%in certain patients.The complications related to the chemotherapy or the surgery ranged from 6.4%to 38.1%in the nAT group and from 5%to 40.5%in the US grou

关键词： Gastric cancer Locally advanced gastric cancer neoadjuvant chemotherapy Surgery Survival

Beyond the SDG 15.3.1 Good Practice Guidance 1.0 using the Google Earth Engine platform: developing a self-adjusting algorithm to detect significant changes in water use efficiency and net primary production

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Big Earth Data 2023年第1期7卷 59-80页

作者： Andrea Markos neil Sims gregory Giuliani Foundation for the Conservation of the Chiquitano Forest Santa CruzBolivia Bolivian national Academy of Sciences La PazBolivia Centre for Earth Observation Space&AstronomyCSIROClaytonAustralia GEO LDn Initiative Institute for Environmental Sciences EnviroSPACE LabUniversity of GenevaGenevaSwitzerland Institute for Environmental Sciences GRID-GenevaUniversity of GenevaGenevaSwitzerland

Monitoring changes in Annual net Primary Productivity(AnPP)is required for reporting on Un Sustainable Development Goal(SDG)Indicator 15.3.1:the proportion of land that is degraded over the total land area.Calibrating time-series observations of AnPP to derive Water Use Efficiency(WUE;a measure of AnPP per unit of evapotranspiration)can minimize the influence of climate factors on AnPP observations and highlight the influence of non-climatic drivers of degradation such as land use changes.Comparing the AnPP and WUE time series may be useful for identifying the primary drivers of land degradation,which could be used to support the Land Degradation neutrality objectives of the Un Convention to Combat Desertification(UnCCD).This paper presents an algorithm for the Google Earth Engine(freely and openly available upon request-http://***/10.5281/zenodo.4429773)to calculate and compare AnPP and WUE time series for Santa Cruz,Bolivia,which has recently experienced an intensification in its land use.This code builds on the Good Practice Guidance document(ver-sion 1)for monitoring SDG Indicator 15.3.1.We use the MODIS 16-day average,250 m resolution to demonstrate that the Enhanced Vegetation Index(EVI)responds faster to changes in water avail-ability than the normalized Difference Vegetation Index(nDVI).We also consider the relationships between AnPP and WUE.Significant and concordant trends may highlight good agricultural practices or increased resilience in ecosystem structure and productivity when they are positive or reducing resilience and functional integrity if negative.The sign and significance of the correlation between AnPP and WUE may also diverge over time.With further analysis,it may be possible to interpret this relationship in terms of the drivers of change in plant productivity and ecosystem resilience.

关键词： Land degradation land productivity water use efficiency Google Earth Engine MODIS Good Practice Guidance SDG 15.3.1

A survey of high resolution image processing techniques for cereal crop growth monitoring

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Information Processing in Agriculture 2022年第2期9卷 300-315页

作者： Sanaz Rasti Chris J.Bleakley n.M.Holden Rebecca Whetton David Langton gregory O’Hare School of Computer Science University College DublinDublinIreland School of Agriculture and Food Science University College DublinDublinIreland School of Biosystems and Food Engineering University College DublinDublinIreland Origin Enterprises plc DublinIreland

This paper presents a survey of image processing techniques proposed in the literature forextracting key cereal crop growth metrics from high spatial resolution, typically proximalimages. The descriptive crop growth metrics considered are: crop canopy cover, aboveground biomass, leaf area index (including green area index), chlorophyll content, andgrowth stage. The paper includes an overview of relevant fundamental image processingtechniques including camera types, colour spaces, colour indexes, and image segmentation. The descriptive crop growth metrics are defined. Reference methods for groundtruth measurement are described. Image processing methods for metric estimation aredescribed in detail. The performance of the methods is reviewed and compared. The surveyreveals limitations in image processing techniques for cereal crop monitoring such as lackof robustness to lighting conditions, camera position, and self-obstruction. Directions forfuture research to improve performance are identified.

关键词： Crop canopy cover Above ground biomass Leaf area index Chlorophyll content Growth stage Cereal image processing

Median arcuate ligament syndrome often poses a diagnostic challenge: A literature review with a scope of our own experience

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World Journal of Gastrointestinal Surgery 2023年第6期15卷 1048-1055页

作者： Alexandros Giakoustidis Stavros Moschonas gregory Christodoulidis Danae Chourmouzi Anna Diamantidou Sophia Masoura Eleni Louri Vasileios n Papadopoulos Dimitrios Giakoustidis Department of Surgery General Hospital PapageorgiouAristotle University of ThessalonikiThessaloniki 56429Greece Fifth Department of Surgery Interbalkan European Medical CentreThessaloniki 55535Greece Department of General Surgery University Hospital of LarissaLarissa 41110Greece

The median arcuate ligament syndrome(MALS)is recognized as a rare clinical entity,characterized by chronic post-prandial abdominal pain,nausea,vomiting,and unintentional weight loss.Due to its vague symptomatology,it is mainly regarded as a diagnosis of exclusion.Patients can often be misdiagnosed for several years before a correct diagnosis is established,also due to a medical team’s clinical suspicion.We present a case series of two patients who suffered from MALS and were treated successfully.The first patient is a 32-year-old woman,presenting with post-prandial abdominal pain and weight loss that have lasted for the past ten years.The second patient,a 50-year-old woman,presented with similar symptomatology,with the symptoms lasting for the last five years.Both cases were treated by laparoscopic division of the median arcuate ligament fibers,which alleviated extrinsic pressure from the celiac artery.Previous cases of MALS were retrieved from PubMed,to assemble a better diagnostic algorithm and propose a treatment method of choice.The literature review suggests an angiography with a respiratory variation protocol as the diagnostic modality of choice,along with the laparoscopic division of the median arcuate ligament fibers as the proposed treatment of choice.

关键词： Median arcuate ligament syndrome Dunbar syndrome Celiac trunk compression syndrome Celiac artery compression syndrome Case series Review

A pilot prospective prevalence study of chronic rhinosinusitis associated with inflammatory bowel disease

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World Journal of Otorhinolaryngology-Head and neck Surgery 2022年第4期8卷 339-344页

作者： India Dhillon Jennifer Ham Ximena Maul gregory Rosenfeld Andrew Thamboo Division of Otolaryngology St.Paul's Sinus CentreUniversity of British ColumbiaVancouverBritish ColumbiaCanada Division of Gastroenterology University of British ColumbiaVancouverBritish ColumbiaCanada

Background:Inflammatory bowel disease(IBD)is characterized by chronic inflammation of the gastrointestinal tract.Extra-intestinal manifestations such as pulmonary diseases have been reported.Chronic rhinosinusitis(CRS),an inflammatory condition of the sinonasal mucosa,has been associated with several lung diseases.Given the relationship between lung and intestinal pathologies,and lung and sinus pathologies,we aimed to determine the prevalence of IBD among CRS patients.Methods:Pilot prevalence study.ninety-two CRS patients were screened for IBD symptoms from October 2018 to January 2020.Patient-reported disease symptoms and overall quality of life were evaluated using the Sino-nasal Outcome Test 22(SnOT-22),Short Inflammatory Bowel Disease Questionnaire(SIBDQ),and EuroQol 5 Dimension 5 Level(EQ-5D-5L)questionnaires.The Modified Lund-Kennedy(MLK)endoscopic and Lund-Mackay(LM)grading systems were used to confirm CRS diagnoses.Individuals who reported subjective symptoms of IBD were referred to a gastroenterologist clinic for further diagnostics.Results:Twenty of the 92(20.2%,95%CI:12.6%-29.8%)CRS patients reported symptoms of IBD and four individuals(4.26%,95%CI:1.17%-10.50%)were sub-sequently diagnosed with IBD.Compared to patients without IBD symptoms(n=72),those with symptoms(n=20)reported significantly worse SnOT-22(P=0.002),SIBDQ(Pnd EQ-5D-3L(P=0.0063)scores.However,these patients did not exhibit significantly different MLK(P=0.81)or LM(P=0.04)scores.Conclusion:The prevalence of IBD may be elevated among individuals with CRS relative to the general Canadian population.This pilot study suggests that CRS with IBD is associated with lower quality of life.Further cross-sectional studies with larger sample sizes are required.

关键词： chronic rhinosinusitis microbiome Modified Lund–Kennedy quality of life Sino-nasal Outcome Test 22(SnOT-22)

The Conceptualization of Qing-Era （1644-1911） Chinese Literature in nineteenth Century Choson （1392-1910） Korea

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2013年第3期7卷 396-421页

作者： gregory n. Evon School of Humanities and Languages The University of New South Wales Sydney NSW2052 Australia

In a poem composed in 1832, the Chosrn-Korean polymath Chrng Yagyong （1762-1836） declared his fidelity towards Confucian literary principles. Chrng＇s poem was a product of an elite education, and in both form and content, it embodied the ideals of the Chosrn elite： written in classical Chinese rather than Korean, it was an expression of cultural self-confidence. From the point of view of nationalism and its emphasis on vernaculars, it seems strange to define oneself through a cosmopolitan written language. But Chrng was no nationalist. He was a Confucian conservative, and the sense of distinction and difference that animated Chrng＇s poem was Confucian and literary. His articulation of such ideals manifested unease over the erosion of Confucian literary values in China and the prospect of the same occurring in Chos6n under Chinese influence. The source of that influence was books imported from China. What Chrng was reacting against was, at root, the commodification of literature and all that had entailed in Ming （1368-1644） and Qing （1644-1911） China. Although such concerns had grown increasingly urgent a half-century before, they had a long pedigree in Choson, stretching back to debates that had arisen in relation to Ming China and the principal emblem of the commodification of literature： commercial bookstores. This paper examines some of the principal differences between Chinese and Korean literary cultures that were embodied in Chang. It therefore begins with a brief overview of Chang and his poem, before turning to a discussion of some key sociopolitical and intellectual features that distinguished Chosrn＇s literary culture from that of China. Sixteenth-century attitudes towards bookstores are discussed to contextualize subsequent worries over Chinese books, with special attention given to the historical and historiographical dimensions of the question, before concluding with an assessment of the final moments of direct Chinese literary influence in Korea.

关键词： Chong Yagyong Chinese literature in Choson Korea literarycommercialization Ming-Qing China Choson Korea