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超音速火焰喷涂碳化物粒径不同的WC-10Co4Cr涂层在粗细磨粒下的磨损性能 被引量:15
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作者 Arash Ghabchi Tommi Varis +3 位作者 Erja Turunen tomi Suhonen S-P Hannula 谢旭霞 《热喷涂技术》 2010年第4期45-51,共7页
改进的ASTM G65橡胶轮测试方法可采用220nm二氧化钛颗粒和368μm的砂粒分别在潮湿和干燥条件下使用。在由碳化物粒径不同(传统和亚微米)的两种粉末所制备的WC-CoCr涂层上开展试验,研究碳化物大小和磨损介质特性对涂层磨损性能的影响。... 改进的ASTM G65橡胶轮测试方法可采用220nm二氧化钛颗粒和368μm的砂粒分别在潮湿和干燥条件下使用。在由碳化物粒径不同(传统和亚微米)的两种粉末所制备的WC-CoCr涂层上开展试验,研究碳化物大小和磨损介质特性对涂层磨损性能的影响。采用扫描电镜对同一位置磨损前后的低倍和高倍形貌进行观察,并分析了涂层的磨损机理。结果表明:磨损机理取决于碳化物和磨粒的相对大小。在样品上进行磨损定量分析,通过调整碳化物尺寸可改善磨损性能,测试涂层的一些力学性能用于对比。 展开更多
关键词 WC-10Co4Cr 超音速火焰喷涂 磨损
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Advantages of white LED lamps and new detector technology in photometry 被引量:11
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作者 tomi Pulli Timo Donsberg +3 位作者 Tuomas Poikonen Farshid Manoocheri Petri Karha Erkki Ikonen 《Light(Science & Applications)》 SCIE EI CAS CSCD 2015年第1期216-222,共7页
Light emitting diode(LED)lighting is becoming more and more popular,as incandescent lamps are being phased out globally.LEDs have several advantages over incandescent lamps,including energy efficiency,robustness,long ... Light emitting diode(LED)lighting is becoming more and more popular,as incandescent lamps are being phased out globally.LEDs have several advantages over incandescent lamps,including energy efficiency,robustness,long lifetime,and good temporal stability.The three latter features make LEDs attractive candidates as new photometric standards.Because the spectra of white LEDs are limited to the visible wavelength range,a novel method for the realization of photometric units based on the predictable quantum efficient detector(PQED)can be utilized.The method eliminates the need of photometric filters that are traditionally used in photometry,and instead relies on carrying out the photometric weighting numerically based on the measured relative spectrum of the source.The PQED-based realization simplifies the traceability chain of photometric measurements significantly as compared with the traditional filter-based method.The measured illuminance values of a white LED deviate by only 0.03%when determined by the new and the traditional methods.The new PQED method has significantly lower expanded uncertainty of 0.26%(k=52)as compared with that of the traditional filter-based method of 0.42%(k=52).Furthermore,when filtered photometers that measure LED lighting are calibrated using LED lamps as calibration sources instead of incandescent lamps,a significant decrease in the uncertainty related to the spectral mismatch correction can be obtained.The maximum spectral mismatch errors of LED measurements decreased on average by a factor of 3 when switching from an incandescent lamp to an LED calibration source. 展开更多
关键词 LED optical metrology PHOTOMETRY standard lamp
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Phenotypic Characterization of Carbapenemase-Producing Enterobacteriaceae Strains in a Referral Teaching Hospital in Yaoundé, Cameroon
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作者 Cecile Ingrid Djuikoue Paule Dana Djouela Djoulako +10 位作者 Rodrigue Kamga Wouambo Charlène Nkouankou tomi Christiane Possi Kiyang Murielle Chantale Tchitchoua Vynnie Manuella Nyatchoutou Blondelle Kitio Messeu Herman Koyouo Tagne Cedric Dylan Seugnou Nana Nadjia Benhamed Hortense Gonsu Kamga Benjamin D. Thumamo Pokam 《Open Journal of Medical Microbiology》 CAS 2023年第1期52-67,共16页
Background: Carbapenemase-producing Enterobacteriaceae (CPE) are an important and increasing threat to global health. They are nowadays more encountered routinely in hospitals and cause high morbidity and mortality du... Background: Carbapenemase-producing Enterobacteriaceae (CPE) are an important and increasing threat to global health. They are nowadays more encountered routinely in hospitals and cause high morbidity and mortality due to limited therapeutic alternatives. This study sought to determine the prevalence of CPE in Yaoundé teaching hospital, Cameroon, and the associated risk factors. Materials and Method: To achieve this goal, a descriptive cross-sectional study coupled to an analytical component with consecutive collection of Enterobacteria strains was carried out during a three-month period (from 27<sup>th</sup> July to 24<sup>th</sup> October 2018) in the University Teaching Hospital of Yaoundé, Cameroon. The oxidase and biochemical identification tests using a miniaturized Api 20 E system were performed on colonies grown on Eosin Methylene Blue (EMB) medium and subcultured on nutrient agar. Drug susceptibility testing was carried out according to the Antibiogram Committee of the French Society of Microbiology (CA-SFM 2018.V.2.0). The detection of carbapenemase production was performed by the CA-SFM 2018 algorithm for the screening of carbapenemase-producing enterobacteriaceae and its classification by inhibitory synergy tests. Results: Out of the 104 isolates, Escherichia coli (50%) was the most prevalent species, followed by Klebsiella pneumoniae (37.5%) and Citrobacter frendii (12.5%). Drugs susceptibility patterns showed a high resistance to penicillins group (97.4% to amoxicillin), cephalosporins (68.4% to cefotaxim, 58.1% to cefixim, 60.7% to ceftazidim, 57.1% of cefoxitin) and aztreonam (55.7%). However, 11.9% carbapenems related resistance was noticed: 14.4% to imipenem, 13.8% to ertapenem and 7.5% to meropenem. Numerous co-resistance to quinolones (65.8%), fluoroquinolones (49.6%), aminoglycosides (49.6%) and cotrimoxazole (71.8%) were also observed. From 104 isolates, AmpC production represented 23.08% (25/104) and 36.54% (38/104) were ESBL-isolates. The overall prevalence of CPE was 25% (26/104) with K 展开更多
关键词 ENTEROBACTERIACEAE ANTIBIOTICS CARBAPENEMASE RESISTANCE
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Clustering Structure Analysis in Time-Series Data With Density-Based Clusterability Measure 被引量:6
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作者 Juho Jokinen tomi Raty Timo Lintonen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1332-1343,共12页
Clustering is used to gain an intuition of the struc tures in the data.Most of the current clustering algorithms pro duce a clustering structure even on data that do not possess such structure.In these cases,the algor... Clustering is used to gain an intuition of the struc tures in the data.Most of the current clustering algorithms pro duce a clustering structure even on data that do not possess such structure.In these cases,the algorithms force a structure in the data instead of discovering one.To avoid false structures in the relations of data,a novel clusterability assessment method called density-based clusterability measure is proposed in this paper.I measures the prominence of clustering structure in the data to evaluate whether a cluster analysis could produce a meaningfu insight to the relationships in the data.This is especially useful in time-series data since visualizing the structure in time-series data is hard.The performance of the clusterability measure is evalu ated against several synthetic data sets and time-series data sets which illustrate that the density-based clusterability measure can successfully indicate clustering structure of time-series data. 展开更多
关键词 CLUSTERING EXPLORATORY data analysis time-series UNSUPERVISED LEARNING
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THE USE OF PLANE WAVES TO APPROXIMATE WAVE PROPAGATION IN ANISOTROPIC MEDIA 被引量:5
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作者 tomi Huttunen Peter Monk 《Journal of Computational Mathematics》 SCIE CSCD 2007年第3期350-367,共18页
In this paper we extend the standard Ultra Weak Variational Formulation (UWVF) of Maxwell's equations in an isotropic medium to the case of an anisotropic medium. We verify that the underlying theoretical framework... In this paper we extend the standard Ultra Weak Variational Formulation (UWVF) of Maxwell's equations in an isotropic medium to the case of an anisotropic medium. We verify that the underlying theoretical framework carries over to anisotropic media (however error estimates are not yet available) and completely describe the new scheme. We then consider TM mode scattering, show how this results in a Helmholtz equation in two dimensions with an anisotropic coefficient and demonstrate how to formulate the UWVF for it. In one special case, convergence can be proved. We then show some numerical results that suggest that the UWVF can successfully simulate wave propagation in anisotropic media. 展开更多
关键词 Ultra weak MAXWELL Plane wave Anisotropic medium.
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Baseline neutrophil-lymphocyte ratio and platelet-lymphocyte ratio appear predictive of immune treatment related toxicity in hepatocellular carcinoma
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作者 Sirish Dharmapuri UmutÖzbek +34 位作者 Hiren Jethra tomi Jun Thomas U Marron Anwaar Saeed Yi-Hsiang Huang Mahvish Muzaffar Matthias Pinter Lorenz Balcar Claudia Fulgenzi Suneetha Amara Arndt Weinmann Nicola Personeni Bernhard Scheiner Tiziana Pressiani Musharraf Navaid Bertram Bengsch Sonal Paul Uqba Khan Dominik Bettinger Naoshi Nishida Yehia Ibrahim Mohamed Arndt Vogel Anuhya Gampa James Korolewicz Antonella Cammarota Ahmed Kaseb Peter R Galle Anjana Pillai Ying-Hong Wan Alessio Cortellini Masatoshi Kudo Antonio D’Alessio Lorenza Rimassa David James Pinato Celina Ang 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第11期1900-1912,共13页
BACKGROUND A well-recognized class effect of immune checkpoint inhibitors(ICI)is immune-related adverse events(IrAEs)ranging from low grade toxicities to life-threatening end organ damage requiring permanent discontin... BACKGROUND A well-recognized class effect of immune checkpoint inhibitors(ICI)is immune-related adverse events(IrAEs)ranging from low grade toxicities to life-threatening end organ damage requiring permanent discontinuation of ICI.Deaths are reported in<5%of patients treated with ICI.There are,however,no reliable markers to predict the onset and severity of IrAEs.We tested the association between neutrophil-lymphocyte ratio(NLR)and platelet-lymphocyte ratio(PLR)at baseline with development of clinically significant IrAEs(grade≥2)in hepatocellular carcinoma(HCC)patients treated with ICI.AIM To test the association between NLR and PLR at baseline with development of clinically significant IrAEs(grade≥2)in HCC patients treated with ICI.METHODS Data was extracted from an international database from a consortium of 11 tertiary-care referral centers.NLR=absolute neutrophil count/absolute lymphocyte count(ALC)and PLR=platelet count/ALC.Cutoff of 5 was used for NLR and 300 for PLR based on literature.We also tested the association between RESULTS Data was collected from 361 patients treated between 2016-2020 across the United States(67%),Asia(14%)and Europe(19%).Most patients received Nivolumab(n=255,71%).One hundred sixty-seven(46%)patients developed at least one IrAE,highest grade 1 in 80(48%),grade≥2 in 87(52%)patients.In a univariable regression model PLR>300 was significantly associated with a lower incidence of grade≥2 IrAEs(OR=0.40;P=0.044).Similarly,a trend was observed between NLR>5 and lower incidence of grade≥2 IrAEs(OR=0.58;P=0.097).Multivariate analyses confirmed PLR>300 as an independent predictive marker of grade≥2 IrAEs(OR=0.26;P=0.011),in addition to treatment with programmed cell death ligand 1(PD-1)/cytotoxic T lymphocyte-associated protein-4(OR=2.57;P=0.037)and PD-1/tyrosine kinase inhibitor(OR=3.39;P=0.01)combinations.Antibiotic use was not associated with IrAE incidence(OR=1.02;P=0.954).Patients treated with steroids had a>2-fold higher incidence of grade≥2 IrAEs(OR=2.74;P<0.001),altho 展开更多
关键词 Neutrophil-lymphocyte ratio Platelet-lymphocyte ratio Inflammatory biomarkers Immunotherapy Immune toxicity
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Electrical Characteristics of Super Capacitors Using KOH Gel
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作者 tomi Ryu Daisuke Tashima 《Journal of Mechanics Engineering and Automation》 2023年第4期111-116,共6页
Despite aqueous electrolytes having a low cost and excellent ionic conductivity,their low withstand voltage of 1.2 V makes them problematic for battery utility because that is a very important factor in battery produc... Despite aqueous electrolytes having a low cost and excellent ionic conductivity,their low withstand voltage of 1.2 V makes them problematic for battery utility because that is a very important factor in battery production.In this research,the possibility of increasing the withstand voltage while maintaining the low cost of aqueous electrolytes was investigated.In this research,the solution electrolyte was made into a viscous solid polymer electrolyte to improve the withstand voltage of the electrolyte.A solid polymer electrolyte was made from sodium polyacrylate and doped with KOH(potassium hydroxide)and pure water.The improvement of the withstand voltage was evaluated by the specific capacitance. 展开更多
关键词 Electric double layer capacitor sodium polyacrylate potassium hydroxide.
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Prevalence of Extended Spectrum Beta-Lactamase-Producing Escherichia coli in Broiler Chickens in YaoundéCapital City of Cameroon
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作者 Cecile Ingrid Djuikoue Charlène Nkouankou tomi +7 位作者 Cedric Seugnou Nana Müller Fotsac Moffo Frédéric Willy Yamdeu Djonkouh Andrea Tchouotou Didi Cedric Ngalani Toutcho Abel Wade Venant Tchokonte-Nana 《Open Journal of Medical Microbiology》 CAS 2022年第4期156-167,共12页
Background: Escherichia coli are ubiquitous bacteria colonising both humans and animals. Extended spectrum β-lactamase-producing E. coli has been selected as a suitable indicator for the monitoring and surveillance o... Background: Escherichia coli are ubiquitous bacteria colonising both humans and animals. Extended spectrum β-lactamase-producing E. coli has been selected as a suitable indicator for the monitoring and surveillance of antimicrobial resistance. Death due to resistant bacteria is continuously rising in Cameroon, but the contribution of the aviary sector is not well studied. Therefore, this study aimed to investigate the resistance profile of extended spectrum beta-lactamases-producing Escherichia coli strains, isolated from faeces of broiler chickens in Yaoundé, capital city of Cameroon. Methods: A cross-sectional descriptive study was carried out from February to June 2020. Escherichia coli were isolated from samples of broilers in poultry farms in Yaoundé and submitted to the extended spectrum β-lactamase screening. The logistic regression was used to assess the statistical association of a significance threshold p-value of 0.05. Results: Out of 385 faecal samples collected in broiler farms, 114 Escherichia coli isolates were obtained out of which 30 (26.32%) were Extended Spectrum Beta-Lactamases-producing Escherichia coli. These isolates revealed high resistance to all antibiotic families. Poor storage conditions for feeds and the proximity to latrines, the troughs on the ground, the lack of foot bath and uniforms, the inadequate treatment of faeces, the poor usage of preventive antibiotics and the lack of water treatment have been identified as risk factors to faecal carriage of ESBL-producing Escherichia coli. Conclusion: This work reveals the emergence of Extended Spectrum Beta-Lactamases-producing Escherichia coli in poultry farms in Yaoundé and the failure in the biosecurity system. As such, the awareness of poultry breeders on the respect of biosecurity measures may be an effective tool to tackle antimicrobial resistance, specifically in livestock industries using a One Health approach. 展开更多
关键词 Extended Spectrum Beta-Lactamase Escherichia coli Antibiotic Resistance Broiler Chicken Yaoundé Cameroon
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Local corticosterone production and angiotensin-Ⅰconverting enzyme shedding in a mouse model of intestinal inflammation 被引量:2
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作者 Hanne Salmenkari tomi Issakainen +1 位作者 Heikki Vapaatalo Riitta Korpela 《World Journal of Gastroenterology》 SCIE CAS 2015年第35期10072-10079,共8页
AIM: To investigate local corticosterone production and angiotensin-Ⅰ converting enzyme(ACE) protein expression and their interaction in healthy and inflamed intestine.METHODS: Acute intestinal inflammation was induc... AIM: To investigate local corticosterone production and angiotensin-Ⅰ converting enzyme(ACE) protein expression and their interaction in healthy and inflamed intestine.METHODS: Acute intestinal inflammation was induced to six weeks old male Balb/c mice by administration of either 3% or 5% dextran sodium sulfate(DSS) in drinking water for 7 d(n = 12 in each group). Healthy controls(n = 12) were given tap water. Corticosterone production and ACE protein shedding were measured from ex vivo incubates of the small and large intestine using EIA and ELISA, respectively. Morphological changes of the intestinal wall were assessed in hematoxylin-eosin stained tissue preparations of jejunum and distal colon. Effects of angiotensin Ⅱ, captopril and metyrapone on corticosterone production was assessed by incubating pieces of small intestine of healthy mice in the presence of 0.1, 1 or 10 μmol/L angiotensin Ⅱ, 1, 10 or 100 μmol/L captopril or 1, 10 or 100 μmol/L metyrapone solutions and measuring corticosterone released to the incubation buffer after 90 min(n = 5 in each group).RESULTS: Both concentrations of DSS induced inflammation and morphological changes in large intestines but not in small intestines. Changes were observed as distortions of the crypt structure, mucosal erosion, immune cell infiltration to the mucosa and submucosal edema. Ex vivo corticosterone production(2.9 ± 1.0 ng/mL vs 2.0 ± 0.8 ng/mL, P = 0.034) and ACE shedding(269.2 ± 97.1 ng/m L vs 175.7 ± 52.2 ng/mL, P = 0.016) were increased in small intestines in 3% DSS group compared to the controls. In large intestine, corticosterone production was increased compared to the controls in both 3% DSS(229 ± 81 pg/mL vs 158 ± 30 pg/mL, P = 0.017) and 5% DSS groups(366 ± 163 pg/mL vs 158 ± 30 pg/mL, P = 0.002). Large intestine ACE shedding was increased in 5% DSS group(41.5 ± 9.0 ng/mL vs 20.9 ± 5.2 ng/mL, P = 0.034). Angiotensin Ⅱ treatment augmented corticosterone production in small intestine at concentration of 10 μmol/L(0.97 ± 0.21 ng/m 展开更多
关键词 DEXTRAN sodium SULFATE Inflammation Angiotensin-I
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Optimal investment analysis for heat pumps and nuclear heat in decarbonised Helsinki metropolitan district heating system 被引量:1
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作者 Esa Pursiheimo tomi JLindroos +2 位作者 Dennis Sundell Miika Rämä Ville Tulkki 《Energy Storage and Saving》 2022年第2期80-92,共13页
Decarbonisation of district heating and cooling(DHC)system in Helsinki metropolitan area requires investments in new energy technologies and approaches to replace fossil fuel fired district heating(DH)production.Inves... Decarbonisation of district heating and cooling(DHC)system in Helsinki metropolitan area requires investments in new energy technologies and approaches to replace fossil fuel fired district heating(DH)production.Invest-ment paths involving(a)DH heat pumps(HPs)from low quality heat sources and(b)small modular nuclear reactors(SMR)are compared by utilising investment analysis based on optimisation model depicting the as-sumed 2030 situation.Several scenarios,with varying assumptions concerning existing DHC system,investment costs and electricity prices,are analysed in terms of new capacity and total annualised costs.The results indicate that the SMR option is more cost-efficient than the HP option with 4-8€/MWh difference in operation costs including annualised investments.Biomass fired boiler investments,enabled in both options,are preferred to HP investments in most scenarios.The cost-efficiency of HP investments is sensitive to investment cost,whereas SMR investments are relatively stable to investment cost variations.Varying electricity market prices affect cost-efficiency of large-scale HPs,and investments in SMR cogeneration units take place only with high electricity prices. 展开更多
关键词 District heating Decarbonisation Heat pumps Small modular reactors Optimisation model
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扁桃斑鸠菊及非洲印楝叶的提取物对链脲佐菌素致糖尿病大鼠肝脏形态学及肝毒性标志物的影响(英文) 被引量:2
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作者 Oluwole Busayo Akinola Gabriel Olaiya Omotoso +2 位作者 Oluwafunmike Sharon Akinola Olufunke Olubusola Dosumu Esther tomi Adewoye 《中西医结合学报》 CAS 2011年第12期1373-1379,共7页
目的:研究扁桃斑鸠菊及非洲印楝叶的提取物对链脲佐菌素致糖尿病大鼠肝脏形态学、肝脏氧化性应激标志物及部分肝脏酶类的影响。方法:大鼠腹腔注射链脲佐菌素致糖尿病。不同治疗组大鼠分别口服扁桃斑鸠菊及非洲印楝叶的提取物(500mg/kg)... 目的:研究扁桃斑鸠菊及非洲印楝叶的提取物对链脲佐菌素致糖尿病大鼠肝脏形态学、肝脏氧化性应激标志物及部分肝脏酶类的影响。方法:大鼠腹腔注射链脲佐菌素致糖尿病。不同治疗组大鼠分别口服扁桃斑鸠菊及非洲印楝叶的提取物(500mg/kg)或二甲双胍(150mg/kg),疗程8周,每周测量大鼠的血糖水平及体质量变化。8周后麻醉处死大鼠。取肝组织制成切片,希夫染色法染色,并测量肝匀浆中丙二醛和谷胱甘肽过氧化物酶的含量;下腔静脉采血,分离血浆,检测血浆中丙氨酸氨基转移酶和天冬氨酸氨基转移酶的活性。结果:二甲双胍及植物提取物均能显著改善糖尿病大鼠的血糖水平,且与糖尿病模型组相比,治疗组的体质量明显增加(P<0.05)。光学显微镜下,各组大鼠的肝脏形态学无明显差别。植物提取物治疗组大鼠的血浆丙氨酸氨基转移酶及天冬氨酸氨基转移酶的活性与正常对照组相比无明显变化(P>0.05),而丙二醛含量明显下降(P<0.05)。结论:扁桃斑鸠菊及非洲印楝叶的提取物对糖尿病大鼠有明显的降糖作用,而肝脏形态学及肝毒性标志物没有明显变化。 展开更多
关键词 糖尿病 实验性 斑鸠菊属 印楝属 植物提取物 肝脏毒性 氧化性应激 大鼠
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Experimental salt cavern in offshore ultra-deep water and well designevaluation for CO_(2) abatement 被引量:2
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作者 Alvaro Maia da Costa Pedro V.M.Costa +12 位作者 Antonio C.O.Miranda Mariana B.R.Goulart Okhiria D.Udebhulu Nelson F.F.Ebecken Ricardo C.Azevedo Sérgio M.de Eston Giorgio de tomi Andre B.Mendes Julio R.Meneghini Kazuo Nishimoto Claudio Mueller Sampaio Camila Brandao Alexandre Breda 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第5期641-656,共16页
This paper presents a proposal for an experimental salt cavern in offshore ultra-deep water for CO2 abatement,including the instrumentation plan and well conceptual design evaluated for carbon capture and storage(CCS)... This paper presents a proposal for an experimental salt cavern in offshore ultra-deep water for CO2 abatement,including the instrumentation plan and well conceptual design evaluated for carbon capture and storage(CCS)application.These studies are based on applied computational mechanics associated with field experimentation that has contributed to the technical feasibility of the underground potash mine at the State of Sergipe in Brazil.This knowhow allowed the stability analysis of several salt caverns for brine production at the State of Alagoas in Brazil and to the drilling through stratified thick layers of salt of the pre-salt reservoirs in Santos Basin.Now,this knowledge has been applied in the design of onshore and offshore salt caverns opened by dissolution for storage of natural gas and CO2.The geomechanical study,through the application of computational mechanics,of offshore giant salt caverns of 450 m high by 150 m in diameter,shows that one cavern can store about 4 billion Sm3 or 7.2 million tons of CO2.Before the construction of the giant cavern,which will be the first gas storage offshore in the world,it has been decided to develop an experimental one,with smaller size,to obtained field parameters.The experimental cavern will allow the calibration of parameters to be used in the structural integrity analysis of the cavern and well for storage of natural gas which is rich in CO2 under high pressure. 展开更多
关键词 Salt cavern Pre-salt reservoir Geomechanical study Carbon capture and storage
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Self-Learning of Multivariate Time Series Using Perceptually Important Points 被引量:2
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作者 Timo Lintonen tomi Raty 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1318-1331,共14页
In machine learning,positive-unlabelled(PU)learning is a special case within semi-supervised learning.In positiveunlabelled learning,the training set contains some positive examples and a set of unlabelled examples fr... In machine learning,positive-unlabelled(PU)learning is a special case within semi-supervised learning.In positiveunlabelled learning,the training set contains some positive examples and a set of unlabelled examples from both the positive and negative classes.Positive-unlabelled learning has gained attention in many domains,especially in time-series data,in which the obtainment of labelled data is challenging.Examples which originate from the negative class are especially difficult to acquire.Self-learning is a semi-supervised method capable of PU learning in time-series data.In the self-learning approach,observations are individually added from the unlabelled data into the positive class until a stopping criterion is reached.The model is retrained after each addition with the existent labels.The main problem in self-learning is to know when to stop the learning.There are multiple,different stopping criteria in the literature,but they tend to be inaccurate or challenging to apply.This publication proposes a novel stopping criterion,which is called Peak evaluation using perceptually important points,to address this problem for time-series data.Peak evaluation using perceptually important points is exceptional,as it does not have tunable hyperparameters,which makes it easily applicable to an unsupervised setting.Simultaneously,it is flexible as it does not make any assumptions on the balance of the dataset between the positive and the negative class. 展开更多
关键词 Positive-unlabelled(PU) learning SELF-LEARNING stopping criterion time series
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Biomarkers for therapy selection in metastatic urothelial cancer
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作者 tomi Jun Jonathan Anker Matthew D.Galsky 《Journal of Cancer Metastasis and Treatment》 2022年第1期579-606,共28页
The treatment of metastatic urothelial cancer(mUC)has been transformed by recent progress in clinical trials and drug development.There are now three therapeutic classes with proven benefits in mUC:chemotherapy,immuno... The treatment of metastatic urothelial cancer(mUC)has been transformed by recent progress in clinical trials and drug development.There are now three therapeutic classes with proven benefits in mUC:chemotherapy,immunotherapy,and targeted therapy.The optimal sequence and combination of these classes remain to be defined.Biomarker development is essential to guide treatment selection at each therapeutic juncture.Two biomarkers,programmed death-ligand 1 expression and fibroblast growth factor receptor alterations,have been incorporated into the mUC treatment paradigm thus far.This review discusses predictive biomarkers in development and their potential to influence mUC treatment selection moving forward. 展开更多
关键词 Metastatic urothelial cancer biomarkers IMMUNOTHERAPY CHEMOTHERAPY targeted therapy antibody-drug conjugates
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The tumor suppressor kinase LKB1:lessons from mouse models 被引量:1
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作者 Saara Ollila tomi P.Makela 《Journal of Molecular Cell Biology》 SCIE CAS CSCD 北大核心 2011年第6期330-340,共11页
Mutations in the tumor suppressor gene LKB1 are important in hereditary Peutz–Jeghers syndrome,as well as in sporadic cancers including lung and cervical cancer.LKB1 is a kinase-activating kinase,and a number of LKB1... Mutations in the tumor suppressor gene LKB1 are important in hereditary Peutz–Jeghers syndrome,as well as in sporadic cancers including lung and cervical cancer.LKB1 is a kinase-activating kinase,and a number of LKB1-dependent phosphorylation cascades regulate fundamental cellular and organismal processes in at least metabolism,polarity,cytoskeleton organization,and proliferation.Conditional targeting approaches are beginning to demonstrate the relevance and specificity of these signaling pathways in development and homeostasis of multiple organs.More than one of the pathways also appear to contribute to tumor growth following Lkb1 deficiencies based on a number of mouse tumor models.Lkb1-dependent activation of AMPK and subsequent inactivation of mammalian target of rapamycin signaling are implicated in several of the models,and other less well characterized pathways are also involved.Conditional targeting studies of Lkb1 also point an important role of LKB1 in epithelial–mesenchymal interactions,significantly expanding knowledge on the relevance of LKB1 in human disease. 展开更多
关键词 LKB1 tumor suppressor mouse model AMPK
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公司责任及其在林产工业中的体现 被引量:1
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作者 Rajat Panwar tomi Rinne +2 位作者 Eric Hansen Heikki Juslin 管宁 《国际木业》 2007年第1期33-34,共2页
工商活动以及社会对其认识经历过很多显著的变化。中世纪流动的商人取代本地的工匠,满足社会对商品的需求是一大变革。社会对这些早期商人常取负面态度,认为他们进行剥削。工业革命使这种情况加剧。工商活动越来越专注于创造财富和谋... 工商活动以及社会对其认识经历过很多显著的变化。中世纪流动的商人取代本地的工匠,满足社会对商品的需求是一大变革。社会对这些早期商人常取负面态度,认为他们进行剥削。工业革命使这种情况加剧。工商活动越来越专注于创造财富和谋求利润而置社会问题于不顾。随着时间的推移,社会管理调控的加强,工商活动的影响及其与社会及环境的相互关系逐渐被认识。自身的进化和社会的关注,使工商活动逐渐重新定向,承担起社会责任,造福于环境和社会。 展开更多
关键词 社会责任 林产工业 社会问题 工业革命 社会管理 商人 环境 商品
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Asthma-associated polymorphisms in 17q12-21 locus modulate methylation and gene expression of GSDMA in naive CD4^+ T cells 被引量:1
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作者 Anne-Marie Madore Lucile Pain +8 位作者 Anne-Marie Boucher-Lafleur Andréanne Morin Jolyane Meloche Marie-Michelle Simon Bing Ge Tony Kwan Warren A.Cheung tomi Pastinen Catherine Laprise 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2020年第3期171-174,共4页
The 17q12-21 locus harboring ORMDL sphingolipid biosynthesis regulator 3(ORMDL3)and Gasdermin B(GSDMB)genes exhibits one of the most significant and replicated associations with asthma[MIM:600807](Stein et al.,2018).S... The 17q12-21 locus harboring ORMDL sphingolipid biosynthesis regulator 3(ORMDL3)and Gasdermin B(GSDMB)genes exhibits one of the most significant and replicated associations with asthma[MIM:600807](Stein et al.,2018).Several studies explored the complex interactions between SNPs,gene expression and epigenetic modifications at this locus,primarily focusing on the levels of expressed ORMDL3 and GSDMB(Stein et al.,2018).Given that DNA methylation and gene expression signals are cell-type specific(Reinius et al.,2012),isolated materials such as lymphocytes from blood and,to a lesser extent,bronchial epithelial cells from biopsies of bronchi or bronchoalveolar lavages have been used in a number of studies to investigate such interactions(Stein et al.,2018). 展开更多
关键词 FDR T cells Asthma-associated polymorphisms gene expression of GSDMA
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3G运营:新商业模式与新生活
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作者 tomi T.Ahonen 王丽娜 《深圳特区科技》 2004年第11期50-54,共5页
关键词 3G移动电话 运营商 3G网络
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具备颜色管理功能的发光二极管驱动器:前景一片璀璨
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作者 tomi Koskela 《电子设计应用》 2007年第9期I0001-I0007,共7页
越来越多移动电话、便携式媒体播放机、电子游戏机以及导航系统等便携式电子消费产品采用彩色发光二极管。一般来说,这些发光二极管都用作指示灯,例如,利用红绿蓝光发光二极管发光的指示灯会根据不同事件如短信服务(SMS)或来电,... 越来越多移动电话、便携式媒体播放机、电子游戏机以及导航系统等便携式电子消费产品采用彩色发光二极管。一般来说,这些发光二极管都用作指示灯,例如,利用红绿蓝光发光二极管发光的指示灯会根据不同事件如短信服务(SMS)或来电,发出不同颜色的灯光。驱动这些发光二极管的方法有很多, 展开更多
关键词 蓝光发光二极管 二极管驱动器 颜色管理 媒体播放机 电子游戏机 移动电话 电子消费 导航系统
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加强便携式设备中的背光照明
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作者 tomi Koskela 《今日电子》 2008年第2期62-64,共3页
现在大部分的便携式电子产品,如移动电话、个人电子手帐、导航系统等,都拥有一个需要背光照明的小型LCD显示屏作为用户界面。人们用这些设备来观看高分辨率的相片、影片和上网浏览的时间亦越来越长。这样,人们对具备媒体存储能力的... 现在大部分的便携式电子产品,如移动电话、个人电子手帐、导航系统等,都拥有一个需要背光照明的小型LCD显示屏作为用户界面。人们用这些设备来观看高分辨率的相片、影片和上网浏览的时间亦越来越长。这样,人们对具备媒体存储能力的高质亮显示屏的需求变得越来越强烈,对背光LED和驱动器技术的挑战也就越大。 展开更多
关键词 便携式设备 背光照明 LCD显示屏 便携式电子产品 移动电话 电子手帐 导航系统 用户界面
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