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Bacteriological challenges to asbestos cement water distribution pipelines

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Journal of Environmental Sciences 2010年第8期22卷 1203-1208页

作者： Dunling Wang D. Roy Cullimore Centre for Sustainable Infrastructure Research Institute for Research in Construction National Research Council Canada 6 Research Drive Regina SK S4S 7J7 Canada Droycon Bioconcepts Inc. 315 Dewdney Avenue Regina SK S4N 0E7 Canada

Asbestos cement （AC） pipes were commonly installed in the drinking water distribution systems from the mid 1920s to the late 1980s. In recent years, an increase in the number of water main breaks has occurred in the AC portions of some pipe networks, which can be partially attributed to the corrosion of the aged pipes. This study evaluated the potential role that microorganisms may have played in the degeneration and failure of AC pipes. In this study, a fresh AC pipe section was collected from the distribution network of the city of regina, Canada and examined for microbiological activities and growth on inside surfaces of pipe sample. Black slime bacterial growths were found to be attached to inner pipe surfaces and a distinctively fibrous internal coating （patina） with iron oxides was formed over the time. The microbial populations inside the patina and the black slime were tested with BART^TM testers. Heterotrophic aerobic bacteria （HAB） and slime forming bacteria （SLYM） dominated in both the black growths and inside the patina. Iron related bacteria, denitrification bacteria and sulfate reducing bacteria were also commonly present. Microbial challenge assays were conducted by submerging the cut segments of the AC pipe into selected bacterial cultures for a period of 10 days under both aerobic and anaerobic environments. Weight changes were determined and the surface morphology was examined for each of the assayed pipe segments. Results indicated that acid producing bacteria, SLYM and HAB could facilitate the pipe weight loss under anaerobic environments.

关键词： asbestos cement pipes drinking water distribution network bacteriological challenges biofilms patina

Evolutionary Techniques for Reverse Auctions

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Intelligent Control and Automation 2013年第4期4卷 371-378页

作者： Shubhashis Kumar Shil Samira Sadaoui Malek Mouhoub Department of Computer Science University of Regina Regina Canada

Winner determination is one of the main challenges in combinatorial auctions. However, not much work has been done to solve this problem in the case of reverse auctions using evolutionary techniques. This has motivated us to propose an improvement of a genetic algorithm based method, we have previously proposed, to address two important issues in the context of combinatorial reverse auctions: determining the winner(s) in a reasonable processing time, and reducing the procurement cost. In order to evaluate the performance of our proposed method in practice, we conduct several experiments on combinatorial reverse auctions instances. The results we report in this paper clearly demonstrate the efficiency of our new method in terms of processing time and procurement cost.

关键词： Winner Determination Combinatorial Reverse Auctions Genetic Algorithms

Structural deformation, metallogenic epoch and genetic mechanism of the Woxi Au-Sb-W deposit, Western Hunan Province, South China

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Science China Earth Sciences 2022年第12期65卷 2358-2384页

作者： Bin LI Deru XU Daoyuan BAI Guoxiang CHI Junfeng DAI Cheng GAO Teng DENG Shaohao ZOU Wen MA Guojian WANG Yuexin LING Guangqian ZENG Yinmin LI State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth Sciences East China University of TechnologyNanchang 330013China Hunan Institute of Geological Survey Changsha 410116China Department of Geology University of ReginaRegina S4S 0A2SaskatchewanCanada

The remobilization,migration,precipitation,and enrichment of ore-forming elements are closely related to ***,detailed regional and ore-field structural analyses are critical for determining the genesis of a mineral *** Jiangnan Orogenic Belt(JOB)is an important gold polymetallic metallogenic belt in South China,which is characterized by multiple periods of gold mineralization in the Paleozoic and ***,the genesis of these gold polymetallic deposits is still not well understood due to a lack of systematic research on the regional geology,ore-controlling structures and metallogenic *** this study,a detailed structural survey at the surface and in the subsurface tunnels was conducted on the Woxi Au-Sb-W deposit,the genesis of which is relatively controversial among the gold polymetallic deposits in the JOB due to poor structural *** addition,a wolframite U-Pb dating was carried out to further constrain the relationship between structures and *** on the results of these studies,together with those from previous studies,it is proposed that the Woxi deposit and surrounding areas likely underwent six periods of regional deformation,which are constrained in time and geodynamic ***,we present a systematic discussion on the roles of ore-controlling structures in the transportation,distribution,and deposition of ore-forming elements and localization of *** to the wolframite dating results,structural analyses,and previous data,we propose that the Woxi Au-Sb-W deposit was formed in two stages during the Yanshanian:a W(wolframite)-Au mineralization stage at ca.140 Ma and an Au-Sb-W(scheelite)mineralization stage at<130 *** mineralizing events are interpreted to have a tight relationship with tectonic reactivation,and the ore-forming fluids were derived from deep sources,including those of magmatic or metamorphic *** Woxi deposit can therefore be classified as an“

关键词： Structural deformation Wolframite U-Pb age Metallogenic epoch Genetic mechanism Woxi Au-Sb-W deposit Western Hunan Province Jiangnan orogen

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Renewed considerations on the utility(or the futility)of hepatic resections for breast cancer liver metastases

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Hepatobiliary Surgery and Nutrition 2021年第1期10卷 49-58页

作者： Gian Luca Grazi Hepatobiliary Biliary Pancreatic Surgery IRCCS Regina Elena National Cancer InstituteRomeItaly

Importance:Indication for liver resection(LR)for localized hepatic metastases from breast cancer(BC)is still a matter of ***:A literature review of recent scientific papers pertaining to hepatectomies for BC liver metastases(LM).Evidence Review:We based our systematic review on case series on literature reviews,comparative studies and cost-utility analysis which have been selected based on criteria regarding surgery,possible prognostic factors and evaluation of long-term ***:There is a strong inhomogeneity in the reported data,with 5-year survivals ranging from 21%to 58%.There is no agreement in the evaluation of prognostic variables predicting good survival,with the only exception of the time of treatment of the primary BC until the diagnosis of *** out of the four comparative studies report better survivals for patients who underwent a hepatectomy in comparison to those treated with chemotherapy alone,but their strength in terms of scientific evidence is *** only cost-utility analysis revealed that 2 out of the 3 scenarios considered were in favor of the treatment with surgery followed by conventional ***:There is no definitive proof on the effectiveness of LRs for BC *** can be proposed when it is possible to perform radical surgery,with R0 margins and saving at least 30%of the liver with its vascular and biliary *** skeletal metastases are not a *** interval between treatment of the primary location and diagnosis of hepatic metastases is the only prognosis criteria available.

关键词： Breast cancer(BC) liver metastases(LM) liver surgery hepatectomy

Model Helicopter Control Using Body-Mounted Vibro-Tactile Transducers

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World Journal of Engineering and Technology 2014年第4期2卷 322-330页

作者： Rui Zhou Merhran Mehrandezh Raman Paranjape Electronic Systems Program Faculty of Engineering University of Regina Regina Canada Industrial Systems Program Faculty of Engineering University of Regina Regina Canada

The sense of touch as a man-machine communication channel can be as acute as the sense of sight and sound. In some scenarios such as those seen in aerobatics, stunt flying, and combat flights, tactile sensors can even outperform the conventional non-contact sensors in terms of situation awareness. Fusion of tactile sensory information with those obtained via sight and sound can avoid diverting the user’s attention away from the operational task at hand as well. In this study, the performance of an operator, to servo control the motion of a 2-dof model helicopter with pitch/yaw maneuverability, subjected to an intuitive body-referenced arrangement of a cluster of vibro-tactile sensors is investigated. A blindfolded operator will then control the helicopter to a safe attraction zone via a joystick based on this tactile sensory information. A fine-tuned local controller would take over for the end-of-motion precise homing. This study can pave the way towards a systematic integration and characterization of tactile sensors in high performance weapon platforms with improved situation awareness in visually awkward maneuvers such as those seen in aerial combat scenarios.

关键词： Haptics Flight Control Linear Quadratic Regulators (LQR) Tactile Immersive Control 2-Dof Model Helicopter Mechatronics Real-Time Control

Colorectal cancer screening behavior and willingness

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World Journal of Gastroenterology 2012年第22期18卷 2885-2886页

作者： Stefano Pontone Department of Surgical Sciences "Sapienza" University of Rome V.le Regina Elena 324 00161 Rome Italy

The outpatient-based study by Deng et al [World J Gastroenterol 2011 July 14; 17(26): 3133-3139] on the factors that may influence the colorectal cancer (CRC) screening feasibility, encouraged our curiosity. Establishing a simple method for quickly assessing the educational level of patients and modulating a questionnaire for each type of patient, may be an effective protocol to increase the people participation, mainly in countries where sufficient medical resources and financial support are lacking. In fact, the knowledge directly affects the feasibility when screening is offered. Patient educational level influences the understanding of the knowledge and the screening method. This factor may affect patient's priority level on the study participation, the understanding of questions, and the motivation to complete the questionnaire and, consequently, the screening success. Recent studies have found a relationship between high educational level and CRC screening participation, and emphasized the question-naire ineffectiveness in the illiterate people. Although the questionnaire is an excellent method for this kind of evaluation, physician's contribution could be the most important factor associated with the screening method. Thus, further studies should be conducted to explore the compliance of patients with low educational level and to look for the best solutions for their enrollment.

关键词： Colorectal cancer Screening Educationallevel Survey Socioeconomic factors

Quantitative study on pollen-based reconstructions of vegetation history from central Canada

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Science China Earth Sciences 2008年第8期51卷 1081-1088页

作者： HART Catherina VETTER Mary SAUCHYN David Department of Biology University of ReginaS4S 0A2Canada Prairie Adaptation Research Collaborative SK S4S 7J7Canada Department of GeographyUniversity of ReginaS4S 0A2Canada

Based on high-resolution pollen records from lake cores in central Canada, the present study instructed pollen taxa assignations in ecosystem groups and modern analogue technique, reported major results of quantitativ... 详细信息

关键词： sedimentary pollen surface pollen modern analogue technique ecosystem paleovegetation past 1000 years

An Example Using Improved Lefschetz Duality

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Chinese Annals of Mathematics,Series B 2017年第6期38卷 1269-1274页

作者： Pascal LAMBRECHTS Jeremy LANE Donald STANLEY Pascal Lambrechts Institut Mathmatique Universit de Louvain Department of Mathemtics University of Toronto Department of Mathematics and Statistics University of Regina

A theorem of Lambrechts and Stanley is used to find the rational cohomology of the complement of an embedding S^(4n-1)→ S^(2n)× S^m as a module and demonstrate that it is not necessarily determined by the map induced on cohomology by the embedding, nor is it a trivial extension. This demonstrates that the theorem is an improvement on the classical Lefschetz duality.

关键词： Lefschetz duality Embedding Extension problem

Unusual retention behavior of omeprazole and its chiral impurities B and E on the amylose tris(3-chloro-5-methylphenylcarbamate)chiral stationary phase in polar organic mode

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Journal of Pharmaceutical Analysis 2018年第4期8卷 234-239页

作者： Rosella Ferretti Leo Zanitti Adriano Casulli Roberto Cirilli Centro nazionale per il controllo e la valutazione dei farmaci Istituto Superiore di Sanita Viale Regina Elena 299 00161 Rome Italy European Union Reference Laboratory for the Parasites Istituto Superiore di Sanita Viale Regina Elena 299 00161 Rome Italy World Health Organization Collaborating Centre for the Epidemiology Detection and Control of Cystic and Alveolar Echinococcosis (In Animals and Humans) Istituto Superiore di Sanita Viale Regina Elena 299 00161 Rome Italy

Recent reports have demonstrated that the new commercially available immobilized-type chiral stationary phases（CSPs） containing amylose tris（3-chloro-5-methylphenylcarbamate）（ACMPC） as a selector exhibit not only an exceptionally high enantioselectivity in high-performance liquid chromatography（HPLC） but they are also applicable to a wide range of chiral analytes. Herein, we report the results obtained in the HPLC analysis of omeprazole and its impurities B and E on the ACMPC-based Chiralpak IG-3 CSP（CSP） under polar organic conditions. A systematic evaluation of the retention characteristics of the selected benzimidazole chiral probes was carried out by changing the composition of the mobile phase and the column temperature. It is worth emphasizing that the high affinity of both enantiomers of all analytes recorded in pure methanol mode dramatically decreased incorporating small volumes of either basic or acid additives in the mobile phase. Unspecified sites of the IG-3 CSP presumably involved in strong and non-stereoselective H-bonding contacts with chiral analytes are assumed responsible for the unproductive retention process.

关键词： Chiralpak IG-3 Retention Enantioselective HPLC Omeprazole Column temperature Basic/acid additives