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Pad-scale control improves SAGD performance

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Petroleum 2018年第3期4卷 318-328页

作者： Tao Guo j.ngyi Wang ian D.Gates Department of Chemical and Petroleum Engineering Schulich School of EngineeringUniversity of CalgaryCanada

Steam Assisted Gravity Drainage(SAGD)is widely used in the Athabasca oil sands deposit to recover *** the viscosity of bitumen is high at original reservoir conditions,heat is required to lower its viscosity to the point it becomes mobile enough to be recovered under gravity *** heat the reservoir,steam is inj.cted into the formation and thus SAGD is energy *** that the fuel used to generate steam is the largest operating cost,the steam-to-oil ratio is one of the key parameter for evaluating the economics of any SAGD ***,the use of dynamic distributed steam inj.ction within a pad of SAGD wellpairs is *** results demonstrate that feedback control leads to improvements of the SOR over that of constant *** results show that the controller is able to detect the“sweet spots”(oil zones with better geological properties)in the reservoir and dynamically deliver more steam to that ***,it reduces the steam inj.ction towards relatively worse quality zones to lower the local SOR.

关键词： Steam-assisted gravity drainage SAGD pad Control strategies PID cSOR Oil sands emissions

Abiotic predictors of fine sediment accumulation in lowland rivers

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International j.urnal of Sediment Research 2022年第1期37卷 128-137页

作者： Morwenn McKenzie j.dy England ian D.L.Foster Martin A.Wilkes Geography and Environment Loughborough University Centre for Agroecology Water & Resilience Coventry University Research Environment Agency Howbery Park Environmental and Geographical Sciences University of Northampton Learning Hub University Drive Geography Department Rhodes University

The delivery of excessive fine sediment (particles<2 mm in diameter) to rivers can cause serious deleterious effects to aquatic ecosystems and is widely acknowledged to be one of the leading contributors to the degradation of rivers *** advances in using biological methods as a proxy,physical measures remain an important method through which fine sediment can be *** aim of this study was to provide further insights into the environmental variables controlling sediment accumulation in lowland gravel bed *** sampled 21 sites,during spring and autumn,selected to cover a gradient of excess fine *** sediment was sampled using a range of methods including visual assessments,the disturbance method,and suspended sediment concentrations.A range of abiotic predictors was measured during sampling,and hydrological and antecedent flow indices were derived from local flow gauging station *** results show reach scale visual estimates of fine sediment to be significantly and highly correlated with fully quantitative estimates of total surface *** regression analysis showed that flow variables (regime,antecedent,and local flow characteristics)were strong predictors of deposited sediment metrics but poor predictors of suspended *** content was shown to be relatively independent of total sediment quantity and is likely driven by other factors which influence the supply and breakdown of organic matter.

关键词： Deposited sediment Suspended sediment Visual assessments Disturbance Sediment sampling

Body Mass Index of North American Participants at the World Masters Games

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j.urnal of Sports Science 2014年第4期2卷 189-194页

作者： Mark DeBeliso Trish Sevene j.e Walsh Kent j. Adams j.rki Kettunen ian T. Heazlewood Mike Climstein Department of Physical Education and Human Performance Southern Utah University Cedar City UT 84720 USA Kinesiology Department California State University Monterey Bay Seaside CA 93955 USA Medical Health and Fitness Clinic Five Dock NSW 2137 A US School of Environmental and Life Sciences Faculty Education Health and Science Charles Darwin University NT 0909 A US Medical Sciences Arcada University of Applied Sciences Helsinki FI-00550 FIN Faculty of Health Science and Medicine Bond University Gold Coast Queensland 4229 A US

WMG （World Masters Games） athletes have either pursued a physically active lifestyle for an extended period of time or have initiated exercise/sport in later life. This unique cohort of middle-aged to older-aged adults remains relatively uninvestigated with regards to various measures of health. With a need for multifaceted solutions to the obesity epidemic, investigating special populations such as those competing in sport at older ages may further the understanding of the nexus between aging, physical activity and obesity. This study aims to investigate the BMI （body mass index） of North American WMG competitors with respect to national health guidelines and demographics. An online survey was utilized to collect demographic information from athletes competing at the Sydney WMG. BMI was derived using the participant＇s height and body mass. A total of 928 （46.7% male, 53.3% female） participants from Canada and the United States （age： 52.6 ± 9.8 years） completed the survey. The top 5 sports in which participants competed were football （25.6%）, track/field （15.4%）, swimming （8.4%）, volleyball （8.2%）, and softball （7.8%）. Female and male BMI （kg/m2） across all sports were：〉 30 （obese： 13.9%）, 25-29.9 （overweight： 34.1%）, 18.5-24.9 （normal： 50.3%）, and 〈18.5 （underweight： 1.7%）. Data indicated that BMI was a health risk factor for 13.9% of the participants and a developing risk factor for 34.1% of the participants. Analysis demonstrated a significantly reduced （P 〈 0.05） classification of obesity of the North American WMG competitors when compared to Canadian and United States national populations. It is believed that adherence to exercise improves indices of general health. A key index of health （obesity） is significantly lower in incidence for North American WMG competitors when compared to Canadian and US populations.

关键词： Masters athletes masters games BMI obesity.

Quantitative determination of vitexin in Passiflora foetida Linn. leaves using HPTLC

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Asian Pacific j.urnal of Tropical Biomedicine 2016年第3期6卷 216-220页

作者： Aussavashai Shuayprom Donruedee Sanguansermsri Phanchana Sanguansermsri ian Hamilton Fraser Nalin Wongkattiya Department of Biochemistry Faculty of Medical Science Naresuan University Department of Microbiology and Parasitology Faculty of Medical Science Naresuan University Centre of Excellence in Medical Biotechnology Faculty of Medical Science Naresuan University School of Chemistry Monash University Program in Biotechnology Faculty of Science Maejo University

Obj.ctive: To establish a simple, rapid, precise and accurate high performance thin layer chromatography(HPTLC) method with densitometric detection for the determination of vitexin in Passiflora foetida Linn.(P. foetida).Methods: Ethanolic extract of the plant leaf powder was used for the experimental *** was performed on silica gel 60 F254 HPTLC plates with ethyl acetate:methanol: distilled water: formic acid in the proportion of 50:2:3:6(v/v), as the mobile phase. The determination was carried out using the densitometric absorbance mode at340 ***: Vitexin response was linear over the range of 2.5–17.5 mg/m L with a correlation coefficient of 0.996. Intraday and interday precision studies showed the relative SD was< 3%. Accuracy of the method was determined and the average recovery was 100.3%.The limit of quantitation and limit of detection were 0.879 and 0.290 mg/m L, *** contents of vitexin in P. foetida leaf extracts were within the range of 0.030%–0.310%.Conclusions: The method was evaluated for sensitivity, accuracy, precision and reproducibility. Each analysis by HPTLC is less expensive than current methods. This method is suitable for routine quality control of raw material of the leaves of P. foetida extract and its products.

关键词： HPTLC Thin layer chromatography Vitexin Passiflora foetida Linn

Early life exposure to per-and polyfluoroalkyl substances(PFASs):A critical review

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Emerging Contaminants 2017年第2期3卷 55-68页

作者： Kerstin Winkens Robin Vestergren Urs Berger ian TCousins Department of Environmental Science and Analytical Chemistry(ACES) Stockholm UniversitySE-10691 StockholmSweden Swedish Environmental Research Institute IVL SE-10031 StockholmSweden Department Analytical Chemistry Helmholtz Centre for Environmental Research(UFZ)DE-04318 LeipzigGermany

Due to the dynamic developmental processes during pregnancy,infancy,childhood and adolescence,exposure to PFASs is hypothesized to have the most pronounced negative effects during this *** this review we critically evaluate the current state of the science regarding human early life exposure processes(until 18 years of age)to per-and polyfluoroalkyl substances(PFASs).Efficient placental transfer of perfluoroalkyl acids(PFAAs)results in relatively high prenatal exposure compared with many neutral organic *** few biomonitoring studies that specifically target infants,toddlers and other children suggest relatively high serum concentrations of perfluorooctane sulfonic acid(PFOS)and perfluorooctanoic acid(PFOA)in early life with peak concentrations occurring sometime before the child reaches 20 *** peak in serum concentrations is most likely explained by exposure via breastfeeding,ingestion of house dust and/or specific contact events with consumer products leading to high body weight normalized estimated daily intakes(EDIs).Although children have higher EDIs of PFASs than adults,these are not always reflected by higher serum levels of PFASs in children in cross-sectional biomonitoring studies due to the confounding effect of age and birth cohort,and different exposure histories due to production *** exposure studies measuring internal and external exposure(for multiple pathways and PFASs)at several time points during early life are strongly encouraged to understand temporal changes in exposure of individual children.A better quantitative understanding of early life exposure processes would help to improve the validity of epidemiological studies and allow informed decisions regarding setting of regulatory thresholds and appropriate mitigation actions.

关键词： life exposure likely

ZIKA-How fast does this virus mutate?

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Zoological Research 2016年第2期37卷 110-115页

作者： ian S.LOGAN 22ParksideDrive ExmouthDevonUKEX84LB

The World Health Organization has declared the present Zika virus epidemic to be a ＇Public Health Emergency of International Concern＇. The virus appears to have spread from Thailand to French Polynesia in 2013, and has since infected over a million people in the countries of South and Central America. In most cases the infection is mild and transient, but the virus does appear to be strongly neurotropic and the presumptive cause of both birth defects in fetuses and Guillain-Barr6 syndrome in some adults. In this paper, the techniques and utilities developed in the study of mitochondrial DNA were applied to the Zika virus. As a result, it is possible to show in a simple manner how a phylogenetic tree may be constructed and how the mutation rate of the virus can be measured. The study showed the mutation rate to vary between 12 and 25 bases a year, in a viral genome of 10 272 bases. This rapid mutation rate will enable the geographic spread of the epidemic to be monitored easily and may also prove useful in assisting the identification of preventative measures that are working, and those that are not.

关键词： Zika Virus Polyprotein Mutation rate Phylogenetic tree

Targeting EZH2 for the treatment of soft tissue sarcomas

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j.urnal of Cancer Metastasis and Treatment 2021年第1期7卷 226-241页

作者： Magdalena Karolak ian Tracy j.net Shipley ZoëS Walters Translational Epigenomics Team Cancer SciencesFaculty of MedicineUniversity of SouthamptonSouthampton SO166YDUK Sarcoma Molecular Pathology Team Divisions of Molecular Pathology and Cancer TherapeuticsThe Institute of Cancer ResearchLondon SM25NGUK.

Soft tissue sarcomas(STS)are a heterogenous group of rare malignancies of mesenchymal origin,affecting both children and *** maj.rity of STS have a poor prognosis and advanced stage at the time of *** treatments for STS largely constitute tumour resection with chemotherapy and/or radiotherapy,and there has been little significant advancement in the application of novel therapies for treatment of these *** current multimodal approach to therapy often leads to long-term side effects,and for some patients,resistance to cytotoxic agents is associated with local recurrence and/or *** is,therefore,a need for novel therapeutic strategies for the treatment of *** advances in epigenetics have implicated the histone methyltransferase,EZH2,in the development and progression of diseases such as breast cancer,lymphoma and more recently *** we will review the current literature for EZH2 in STS,including high expression of EZH2 in STS and correlation of this with specific features of malignancy(metastasis,histological grade,and prognosis).The effects of targeting EZH2 using RNA interference and small molecule inhibitors will also be reviewed and the potential for the use of EZH2 inhibition in therapeutic strategies for STS patients will be discussed.

关键词： EZH2 epigenetics therapy

东南极格罗夫山新生代沉积岩漂砾陆相孢粉研究

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微体古生物学报 2013年第2期30卷 113-122页

作者：韦利杰刘小汉 j.ian RAINE 周学君中国科学院地质与地球物理研究所北京100029 中国科学院青藏高原研究所北京100101 新西兰地质与核科学研究所

格罗夫山沉积岩漂砾是东南极兰伯特冰川活动所遗留下来的新生代沉积物,因而是研究东南极冰盖历史演化的直接证据。格罗夫山沉积岩漂砾所含孢粉非常稀少,其孢粉组合特征以低丰富度草本植物花粉为主,伴有少量其它被子植物和藻类孢子。虽... 详细信息

格罗夫山沉积岩漂砾是东南极兰伯特冰川活动所遗留下来的新生代沉积物,因而是研究东南极冰盖历史演化的直接证据。格罗夫山沉积岩漂砾所含孢粉非常稀少,其孢粉组合特征以低丰富度草本植物花粉为主,伴有少量其它被子植物和藻类孢子。虽然孢粉的种类和数量不足以重建原始的植物群落,但至少可以为晚新生代南极大陆古植被提供信息。暗示草本-苔原植被或许发育,气候类似于现今温凉-寒冷的亚南极地区。格罗夫山沉积岩漂砾中稀有的陆相孢粉可能是由于沉积时期周围陆地稀有的边缘植被产生的,也可能由于快速沉积稀释的结果。

关键词：孢粉古植被新生代格罗夫山东南极

Abundance of White-fronted Parrots and diet of an urban parrot assemblage(Aves:Psittaciformes)in a green Neotropical city

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Avian Research 2022年第1期13卷 36-42页

作者： CristelAlvarez-Castillo ian MacGregor-Fors Stefan LArriaga-Weiss Claudio Mota-Vargas Diego Santiago-Alarcon Biología y Conservación de Vertebrados Instituto de EcologíaA.C.-CONACYTXalapaMexico Biological and Environmental Sciences University of HelsinkiLahtiFinland División Académica de Ciencias Biológicas Universidad Juárez Autónoma de TabascoVillahermosaMexico Biología Evolutiva Instituto de EcologíaA.C.-CONACYTXalapaMexico Department of Integrative Biology University of South FloridaTampaUSA

Urban ecosystems are evolutionarily recent novel environments acting as biodiversity *** birds are considered successful urban adapters mainly due to their generalist feeding and opportunistic behavior,allowing them to occupy environments from cold temperate to dry xeric ***,it is important to understand how these species interact in the urban *** studied the interannual(2013–2016)abundance of the White-fronted Parrot(Amazona albifrons)in the Neotropical cities of Xalapa and Coatepec,in Central Veracruz,Mé***,we studied the feeding ecology during 13 months of 6 parrot species detected in the city of *** abundance of the White-fronted Parrot was significantly higher in Xalapa than in Coatepec,and it was homogeneous across ***-native plants represented 30–41%of Psittacidae diets in Xalapa,where seeds were the most commonly consumed *** recorded the highest Psittacidae species richness and highest diet overlap among species by the end of the dry season(April–May).The White-fronted Parrot had the highest plant richness in its diet,followed by the Monk Parakeet(Myiopsitta monachus)and the Green Parakeet(Psittacara holochlorus);yet,the White-fronted Parrot had a specialized diet dominated by two plant species(Grevillea robusta and Ficus aurea).The diet overlap among the three above-mentioned parrot species was not significantly different to a null model,where the White-fronted Parrot and the Monk Parakeet overlapped during the months of February,April,j.ne,and *** White-fronted Parrot is an urban adapter that has successfully expanded its geographic range via natural means and by human *** invasive Monk Parakeet is currently restricted to one park in Xalapa,and it has remained in that stage for many years(i.e.,pre-expansion phase).Exotic plant species in Xalapa represent∼55%of the woody vegetation,some of which have longer flowering and fruiting periods that may have aided the s

关键词： Biological invasions Feeding ecology Population biology Psittacidae Urban ecology