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Rolling Bearing Condition Monitoring Technique Based on Cage Rotation Analysis and Acoustic Emission

Journal of Dynamics, Monitoring and Diagnostics 2022年第2期1卷 57-65页

作者： matías marticorena Oscar García Peyrano Vibrations Laboratory Vibrations DivisionNational Atomic Energy CommissionSan Carlos de BarilocheArgentina Balseiro Institute Cuyo National UniversitySan Carlos de BarilocheArgentina

In this paper,we present an alternative technique for detecting changes in the operating conditions of rolling element bearings(REBs)that can lead to premature *** developed technique is based on measuring the kinematics of the bearing *** rotational motion of the cage is driven by traction forces generated in the contacts of the rolling elements with the *** is known that the cage angular frequency relative to shaft angular frequency depends on the bearing load,the bearing speed,and the lubrication condition since these factors determine the lubricant film thickness and the associated traction *** a large percentage of REB failures are due to misalignment or lubrication problems,any evidence of these conditions should be interpreted as an incipient *** this paper,a novel method for the measurement of the instantaneous angular speed(IAS)of the cage is *** method is evaluated in a deep groove ball bearing test rig equipped with a cage IAS sensor,as well as a custom acoustic emission(AE)transducer and a piezoelectric *** IAS of the cage is analyzed under different bearing loads and shaft speeds,showing the dependence of the cage angular speed with the calculated lubricant film *** bearing faulty operating conditions(mixed lubrication regime,lubricant depletion,and misalignment)are *** is shown that the cage IAS is dependent on the lubrication regime and is sensitive to *** AE signal is also used to evaluate the lubrication *** results suggest that the proposed technique can be used as a condition monitoring tool in industrial environments to detect abnormal REB conditions that may lead to premature failure.

关键词： acoustic emission cage instantaneous angular speed condition monitoring cyclostationary analysis rolling element bearing

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Online Unbalance Detection and Diagnosis on Large Flexible Rotors by SVR and ANN trained by Dynamic Multibody Simulations

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Journal of Dynamics, Monitoring and Diagnostics 2022年第3期1卷 139-147页

作者： Oscar García Peyrano Juan Vignolo Rodrigo Mayer matías marticorena Balseiro Institute Cuyo National UniversitySan Carlos de BarilocheArgentina GPSignal San Carlos de BarilocheArgentina Vibrations Laboratory Vibration DivisionNational Atomic Energy CommissionSan Carlos de BarilocheArgentina

Multiple-stage steam turbine generators,like those found in nuclear power plants,pose special challenges with regards to mechanical unbalance *** factors contribute to a complex vibrational response,which can lead to incorrect assessments if traditional condition monitoring strategies are used without considering the mechanical system as a ***,in turn,can lead to prolonged machinery *** machine learning techniques can be used to integrally correlate mechanical unbalance along the shaft with transducer signals from rotor ***,this type of machinery has scarce data regarding faulty ***,a variety of fault conditions can be simulated in order to generate these data using computational models to simulate the dynamic response of individual *** the present work,a multibody model of a 640MWsteam turbine flexible rotor is employed to simulate mechanical unbalance in several positions along the *** components of the resulting vibration signals at each bearing are obtained and utilized as training data for two regression models designed for mechanical unbalance *** first approach uses an artificial neural network and the second one utilizes a support vector regression *** order to test their performance,the stiffness of each bearing in the multibody simulation was altered between 50%and 150%of the training model values,random noise was added to the signal and several dynamic unbalance conditions were *** show that both approaches can reliably diagnose dynamic rotor unbalance even when there is a typical degree of uncertainty in bearing stiffness values.

关键词： condition monitoring mechanical unbalance machine learning steam turbine

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New Precipitation and Temperature Grids for Northern Patagonia： Advances in Relation to Global Climate Grids

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Journal of Meteorological Research 2016年第1期30卷 38-52页

作者： Emilio Bianchi Ricardo Villalba Maximiliano Viale Fleur Couvreux Rocio marticorena instituto nacional de tecnología agropecuaria estación experimental agropecuaria barilocheModesta Victoria 4450BarilocheArgentina consejo nacional de investigaciones científicas y tcnicas Argentina instituto argentino de nivología glaciología y ciencias ambientales-consejo nacional de investigaciones científicas y tcnicasMendozaRuiz LealMendozaArgentina centre national de recherches mtorologiques(cnrm-game) Mdtdo-FranceToulouseFrance autoridad interjurisdiccional de cuencas Argentina

Climate data of mean monthly temperature and total monthly precipitation compiled from different sources in northern Patagonia were interpolated to 20-km resolution grids over the period 1997-2010. This northern Patagonian climate grid （NPCG） improves upon previous gridded products in terms of its spatial resolution and number of contributing stations, since it incorporates 218 and 114 precipitation and temper- ature records, respectively. A geostatistical method using surface elevation from a Digital Elevation Model （DEM） as the ancillary variable was used to interpolate station data into even spaced points. The maps provided by NPCG are consistent with the broad spatial and temporal patterns of the northern Patagonian climate, showing a comprehensive representation of the latitudinal and altitudinal gradients in temperature and precipitation, as well as their related patterns of seasonality and continentality. We compared the per- formance of NPCG and various other datasets available to the climate community for northern Patagonia. The grids used for the comparison included those of the Global Precipitation Climatology Project, ERA- Interim, Climate Research Unit （University of East Anglia）, and University of Delaware. Based on three statistics that quantitatively assess the spatial coherence of gridded data against available observations （bias, MAE, and RMSE）, NPCG outperforms other global grids. NPCG represents a useful tool for understand- ing climate variability in northern Patagonia and a valuable input for regional models of hydrological and ecological processes. Its resolution is optimal for validating data from the general circulation models and working with raster data derived from remote sensing, such as vegetation indices.

关键词： northern Patagonia precipitation temperature co-kriging climate grids Cordillera de los Andes

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An air quality forecasting system in Beijing-Application to the study of dust storm events in China in May 2008

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Journal of Environmental Sciences 2012年第1期24卷 102-111页

作者： Benoit Laurent Fanny Velay-Lasry Richard Ngo Claude Derognat Batrice marticorena Armand Albergel Laboratoire Inter-universitaire des Systèmes Atmosphriques Laboratorie mixte Paris VII-UPEC-CNRSUMR 7583CrteilFrance ARIA Technologies Boulogne-BillancourtFrance

An air pollution forecast system,ARIA Regional,was implemented in 2007–2008 at the Beijing Municipality Environmental Monitoring Center,providing daily forecast of main pollutant *** chemistry-transport model CHIMERE was coupled with the dust emission model MB95 for restituting dust storm events in springtime so as to improve forecast *** storm events were sporadic but could be extremely intense and then control air quality indexes close to the source areas but also far in the Beijing area.A dust episode having occurred at the end of May 2008 was analyzed in this article,and its impact of particulate matter on the Chinese air pollution index （API） was *** our estimation,about 23 Tg of dust were emitted from source areas in Mongolia and in the Inner Mongolia of China,transporting towards *** episode of dust storm influenced a large part of North China and East China,and also South *** model result was then evaluated using satellite observations and in situ *** simulated daily concentrations of total suspended particulate at 6：00 UTC had a similar spatial pattern with respect to OMI satellite aerosol *** evolution of dust plume was evaluated by comparing dust aerosol optical depth （AOD） calculated from the simulations with AOD derived from MODIS satellite ***,the comparison of reported Chinese API in Beijing with API calculated from the simulation including dust emissions had showed the significant improvement of the model results taking into accountmineral dust correctly.

关键词： dust particulate matter modeling Beijing air quality forecast and analysis system

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Ocular trauma in an urban Spanish population:epidemiology and visual outcome

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International Journal of Ophthalmology(English edition) 2021年第9期14卷 1327-1333页

作者： Marta Belmonte-Grau Guadalupe Garrido-Ceca Paula marticorena-álvarez Department of Ophthalmology Hospital Universitario de La PrincesaMadrid 28006Spain Universidad Autónoma de Madrid Medicine UniversityMadrid 28006Spain

AIM:To describe epidemiological aspects,clinical findings,and visual results in eye trauma patients requiring urgent surgery at a tertiary ***:Retrospective review of adult patients requiring urgent surgery for trauma to the eyeball from January 2010 and April *** was collected relative to age,gender,mechanism of the injury,type of wound,initial and final visual acuity,number and type of surgeries carried *** were classed according to the Birmingham Eye Trauma Terminology(BETT)and the Ocular Trauma Score(OTS)***:The survey included 92 *** age was 54.76±22.18 *** most frequent cause was domestic accidents(44.6%),followed by aggression(22.80%)and occupational accidents(17.4%).Trauma from aggression was more frequent in men(P=0.006)and accidents in the home more common in women(P=0.011).Patients over 65 y presented an odds ratio(OR)of 10.71 for suffering a domestic *** between 15-45 and 46-65 y were at higher risk of trauma from aggression(OR=17.52 and OR=10.94,respectively).As for the type of injury,63.04%were open-globe lesions,Zone II being the most frequently affected(27.2%).In Logistic regression analysis,old age(P=0.05)and retinal involvement(P=0.001)were found to be associated with higher rate of unfavourable visual ***:The epidemiological aspects of eye trauma are highly dependent on the area of population *** accidents are more relevant than workplace accidents in older urban areas with high socioeconomic status.A better knowledge of the epidemiological characteristics is useful for implementing specific prevention measures and appropriate treatment strategies.

关键词： ocular trauma epidemiology domestic accident

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CRISPR/Cas9: Development and Application in Rice Breeding

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Rice science 2019年第5期26卷 265-281页

作者： Fernando matías ROMERO Andrés GATICA-ARIAS Laboratory of Plant Biotechnology School of Biology/Research Center in Cellular and Molecular Biology University of Costa Rica

Rice(Oryza sativa L.)is an important staple food crop worldwide due to its adaptability to different environmental *** of its great economic and social importance,there is a constant requirement for new varieties with improved agronomic characteristics,such as tolerance to different biotic(such as bacterium,fungus,insect and virus)and abiotic stresses(such as salinity,drought and temperature),higher yield and better organoleptic and nutritional *** the new genome editing technologies,the clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas)(CRISPR/Cas)system allows precise and specific edition in a targeted genome *** is one of the most frequently used techniques for the study of the function of new genes and for the development of mutant lines with enhanced tolerance to biotic and abiotic stresses,herbicide resistance or improved *** wide varieties of applications for this technology include simple non-homologous end joining,homologous recombination,gene replacement,and base *** this review,we analyzed how some of these applications have been used in rice cultivars to obtain rice varieties better adapted to current environmental conditions and market requirements.

关键词： rice CRISPR Cas genome editing biotic stress abiotic stress yield off-target mutation

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Ethical and legal implications of gene editing in plant breeding:a systematic literature review

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第12期24卷 1093-1105页

作者： Siti Hafsyah IDRIS Nurzatil Sharleeza mat JALALUDDIN Lee Wei CHANG Faculty of Law Universiti Teknologi MARAJalan Sarjana 1/2Shah Alam 40450SelangorMalaysia Centre for Research in Biotechnology for Agriculture(CEBAR) Level 3Research Management and Innovation ComplexUniversiti MalayaKualaLumpur50603Malaysia Centre for Civilisational Dialogue Level 1High Impact Research BuildingUniversiti MalayaKuala Lumpur 50603Malaysia

Biotechnology policies and regulations must be revised and updated to reflect the most recent advances in plantbreeding technology. New Plant Breeding Techniques(NPBT) such as gene editing have been applied to address the myriad of challenges in plant breeding, while the use of NPBT as emerging biotechnological tools raises legal and ethical concerns. This study aims to highlight how gene editing is operationalized in the existing literature and examine the critical issues of ethical and legal issues of gene editing for plant breeding. We carried out a systematic literature review(SLR) to provide the current states of ethical and legal discourses surrounding this topic. We also identified critical research priority areas and policy gaps that must be addressed when designing the future governance of gene editing in plant breeding.

关键词： Systematic literature review Gene editing Plant breeding Ethical and legal issues Consequentialism Virtue ethics principles

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Prevalence of gastrointestinal nematodiasis and coccidiosis in goats from three selected farms in Terengganu,Malaysia

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Asian Pacific Journal of Tropical Biomedicine 2016年第9期6卷 735-739页

作者： Afzan mat Yusof Muhammad Lokman Md Isa Department of Biomedical Science Kulliyyah of Allied Health SciencesInternational Islamic University Malaysia Integrated Cellular and Molecular Biology Cluster(iMolec) Integrated Centre for Animal Care and UseInternational Islamic University Malaysia

Objective:To reveal the prevalence of gastrointestinal nematodiasis,Trichostrogylus,Haemonchus,Strongyloides and Trichuris and coccidiosis,mainly Eimeria in kids,yearlings and adult ***:A total of 287 goat faecal specimens were randomly collected from three farms in Kuala Terengganu,Setiu and ***:Prevalence of coccidiosis(89.2%) was significantly higher(Pmatodiasis(52.3%).Gastrointestinal nematodes(GINs) were found in37.0% kids,63.5% yearlings and 53.3% *** of GINs revealed the predominance of Strongyloides(45.6%) followed by Trichostrogylus(12.9%),Haemonchus(11.8%) and Trichuris(8.7%) in all groups whereby the adult goats recorded the highest infections of Trichostrogylus(20.5%),Haemonchus(10.6%),Strongyloides(51.5%) in all *** age-specific intensity for Eimeria was in following order:kids(92.6%),adults(86.6%) and yearlings(51.5%) and the difference was not significant(P > 0.05).The concurrent infections between GINs and Eimeria were 67.94% in all *** of Trichostrongylus(17.4%),Haemonchus(15.15%) and Strongyloides(40.4%) with Eimeria had infected most adult *** infections of Trichostrongylus with Eimeria and Trichuris with Eimeria were significantly higher in adults than yearlings and kids(P < 0.05).Conclusions:GINs and Eimeria were widely distributed in the goats leading to higher risk of morbidity and mortality.

关键词： Age Coccidia Goat Nematodes Terengganu

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Effect of combination of Gynura procumbens aqueous extract and Trigona spp. honey on fertility and libido of streptozotocin-induced hyperglycaemic male rats

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Asian pacific Journal of Reproduction 2019年第2期8卷 56-62页

作者： Khaidatul Akmar Mahanem mat Noor Centre for Biotechnology and Functional Food Faculty of Science and TechnologyUniversiti Kebangsaan MalaysiaBangiSelangorMalaysia

Objective: To study the effects of co-administration of Gynura procumbens (GP) and kelulut honey (KH) on male fertility and libido in diabetes-induced rats. Methods: A total 42 males Sprague Dawley rats aged 8 weeks were randomly and equally divided into six different groups. All groups except a normal control group were induced with 50 mg/kg of streptozotocin (STZ) intravenously to induce diabetes. A positive control group was treated with an antidiabetic drug, metformin (500 mg/kg) whereas a negative control group remained untreated throughout the experiment. Meanwhile, another three treatments on diabetic rat groups were performed and categorised as Group 1 (450 mg/kg GP+ 300 mg/kg KH), Group 2 (450 mg/kg GP + 600 mg/kg KH) and Group 3 (450 mg/kg GP+ 1200 mg/kg KH). Treatments were given for seven consecutive days through oral gavage and all rats were euthanized on day 8th for fasting blood glucose analysis, sperm quality, spermatogenesis, sexual behaviour and implantation sites analysis. Results: Fasting blood glucose levels were significantly reduced after treatment of GP and KH, compared to negative and positive controls. The treated groups showed significant increment in sperm quality compared to all control groups. Testes histology illustrated significant damages on leydig and sertoli cells for both negative and positive controls. On the contrary, co-administration of GP and KH displayed regeneration of leydig and sertoli cells in the testes. Additionally, the number of implantation sites significantly increased in females copulated with treated groups, compared to controls. Besides, the libido analysis displayed improvement of libido in treated groups, compared to all controls. Throughout the study, insignificant variances were recorded between the treated groups, indicating that treatment in Group 1 was sufficient to trigger significant improvement on fasting blood glucose level, fertility, and libido in diabetic male rats. Conclusions: Co-administration o

关键词： Diabetes mellitus Gynura procumbens Trigona spp. Honey Sperm quality Spermatogenesis

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Valorization of fruit waste from Cucurbitaceae family:Profiling of phytoconstituent of Benincasa hispida and Citrullus lanatus rinds using ultrasound-assisted extraction

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Food Bioscience 2023年第1期51卷 1317-1323页

作者： Ida Madiha Yusoff Lee Suan Chua Zarani mat Taher Herbal and Phytochemical Unit Institute of Bioproduct DevelopmentUniversiti Teknologi Malaysia81310UTM SkudaiJohor BahruJohorMalaysia Department of Bioprocess and Polymer Engineering School of Chemical and Energy EngineeringFaculty of EngineeringUniversiti Teknologi Malaysia81310UTM SkudaiJohor BahruJohorMalaysia

Food agricultural waste from fruit products such as rinds can be one source of environmental ***,the study was conducted to investigate the total phenolic content,total flavonoid content,antioxidant property,and chemical profiling using gas chromatography-mass spectrometer(GC-MS)and high-performance liquid chromatography tandem mass spectrometry of triple quadrupole(HP LCMS-MS QTOF).Ultrasoundassisted extraction for 45 min was used as a green technique to extract bioactive compounds from watermelon(Citrullus lanatus)and wintermelon(Benincasa hispida)*** total phenolic content and total flavonoid content of ultrasound-assisted extraction were compared with maceration *** revealed by the results,maceration technique had a lower total phenolic content for both *** rind(7.07±0.86μg GAE/mg)and *** rind(13.87±0.11μg GAE/mg)compared to ultrasound-assisted *** similar trends can be observed in total flavonoid content of *** rind(4.97±0.29μg RE/g)and *** rind(8.30±0.17μg RE/g)by maceration which showed a lower quantity compared to ultrasound-assisted *** ultrasound-assisted extraction was selected for further *** total phenolic content assay found that the *** rind extract exhibited higher total phenolic content values(23.39±0.22μg GAE/mg),than *** rind extract(15.10±0.58μg GAE/mg).*** rind extract had a higher total flavonoid content(11.17±0.17μg RE/g)than *** rind extract(6.16±0.09μg RE/g).The antioxidant activity was investigated using DPPH scavenging *** antioxidant capacity of *** rind extract(20872.19±1301.47 mg/mL)stronger compared to *** rind extract(23514.47±678.70 mg/mL).Results revealed that there was a negative correlation between total phenolic content,total flavonoid content,and DPPH scavenging activity *** phytoconstituent determination in *** and *** rind extract showed both contained phenolic,malic acid,and other co

关键词： Ultrasonic Fruit by-product Phenolic Flavonoid Antioxidant

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