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Physical and chemical characterization of sediments from an Andean river exposed to mining and agricultural activities: The Moquegua River, Peru

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International Journal of Sediment Research 2022年第6期37卷 780-793页

作者： Luis de Los Santos Valladares Juan Luis Ccamapaza Renato Arturo Valencia-Bedregal Luis Enrique Borja-Castro Jose Velazquez-garcia Dehiwalage Harshani Nimalika Perera Adrian Ionescu david Arvidsson Eustace Peregrine Barnes Peter Newton Hugo Lepage Patrick Byrne Angel Guillermo Bustamante Dominguez Crispin H.W.Barnes Cavendish Laboratory Department of Physics University of Cambridge Escuela Acad emico Profesional de Ingeniería Ambiental Universidad Nacional de Moquegua Provincia de Mariscal Nieto Laboratorio de Cer amicos y Nanomateriales Facultad de Ciencias Físicas Universidad Nacional Mayor de San Marcos School of Biological and Environmental Science Liverpool John Moores University

This study presents an analysis of sediments in an Andean river impacted by both natural conditions and anthropogenic activities. Fifty samples were collected from selected sites throughout the Moquegua River drainage basin, and Tambo River headwaters at Pasto Grande, in Peru, and analysed with X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy and thermogravimetric analysis. Si, Ca, Al, Fe, and O, common constituents of soils, were dominant, along with K, N, and P. The latter originating as primary macronutrients or chemical residuals from fertilizers used in agriculture. Higher concentrations of macronutrients and organic components were found in agricultural and urban areas, respectively. Arsenic minerals were also detected, which occur naturally, but possibly at levels augmented by anthropogenic activity. The application of cluster analysis revealed clustering between arsenic, arsenolite, and potassium but no significant geospatial correlation between sample sites in the drainage basin.

关键词： Andean river Moquegua river Sediments Fourier-transform infrared spectroscopy TG-DTG/DTA Clustering analysis

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XAANTAL2 （AGL14） Is an Important Component of the Complex Gene Regulatory Network that Underlies Arabidopsis Shoot Apical Meristem Transitions

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Molecular Plant 2015年第5期8卷 796-813页

作者： Rigoberto V. Perez-R.u.iz Berenice garcia-Ponce Nayelli Marsch-Martinez Yamel Ugartechea-Chirino Mitzi Villajuana-Bonequi Stefan de Folter Eugenio Azpeitia Jose Davila-Velderrain david Cruz-Sanchez Adriana Garay-Arroyo Maria de la Paz Sanchez Juan M. Estevez-Palmas Elena R. Alvarez-Buylla Instituto de Ecologia Universidad Nacionat Autonoma de Moxico 3er Circuito Exterior s/no Junto al Jardin Bot~nico and Centro de Ciencias de la ComplejidadCiudad Universitaria Coyoacan 04510 Mexico D.F. Mexico Laboratorio Nacional de Genemica para la Biodiversidad (Langebio) Centro de Investigaci6n y de Estudios Avanzados del Instituto Polit~cnico Nacional(CINVESTAV-IPN) Km. 9.6 Carretera Irapuato - Leen AP 629 36821 Irapuato Guanajuato Mexico University of California 431 Koshland Hall Berkeley CA 94720 USA These authors contributed equally to this article. present address: Departamento de Biotecnologia y Biquimica Centro de )nvestigaci6n y de Estudios Avanzados del Instituto Polit6cnico Nacional(CINVESTAV-IPN) Km. 9.6 Libramiento Norte Carr. Irapuato-Leen 36821 Irapuato Guanajuato Mexico present address: Max Planck Institute for Plant Breeding Research D-50829 Cologne Germany Present address: INRIA Project-Team Virtual Plants/CIRAD/INRA UMR AGAP Campus St Priest - BAT 5 CC 05018 860 rue de St Priest 34095 Montpellier Cedex5 France

In Arabidopsis thaliana, multiple genes involved in shoot apical meristem （SAM） transitions have been char- acterized, but the mechanisms required for the dynamic attainment of vegetative, inflorescence, and floral meristem （VM, IM, FM） cell fates during SAM transitions are not well understood. Here we show that a MADS-box gene, XAANTAL2 （XAL2/AGL14）, is necessary and sufficient to induce flowering, and its regula- tion is important in FM maintenance and determinacy, xal2 mutants are late flowering, particularly under short-day （SD） condition, while XAL2 overexpressing plants are early flowering, but their flowers have vege- tative traits. Interestingly, inflorescences of the latter plants have higher expression levels of LFY, AP1, and TFL1 than wild-type plants. In addition we found that XAL2 is able to bind the TFL1 regulatory regions. On the other hand, the basipetal carpels of the 35S：：XAL2 lines lose determinacy and maintain high levels of WUS expression under SD condition. To provide a mechanistic explanation for the complex roles of XAL2 in SAM transitions and the apparently paradoxical phenotypes of XAL2 and other MADS-box （SOCl, AGL24） over- expressors, we conducted dynamic gene regulatory network （GRN） and epigenetic landscape modeling. We uncovered a GRN module that underlies VM, IM, and FM gene configurations and transition patterns in wild- type plants as well as loss and gain of function lines characterized here and previously. Our approach thus provides a novel mechanistic framework for understanding the complex basis of SAM development.

关键词： XAL2/AGL14 MADS-box TFL1 SAM transitions floral reversion gene regulatory networks,epigenetic landscape modeling

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Determining a Diagnostic Cut-Off on Fluorescence Polarization Assay(FPA)for Bovine Brucellosis in Carchi,Ecuador

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Open Journal of Animal Sciences 2017年第4期7卷 425-432页

作者： Ibarra Marcelo Benavides Hernan Salgado Ruth Gutierrez Milena garcia Judith Pena Julio Herrera david Mina Jorge Campos Martin Puga Byron Agricultural Career Carchi State Polytechnic UniversityTulcánEcuador School of Veterinary Medicine and Animal Science Central University of EcuadorQuitoEcuador

Serology is the foundation of any brucellosis control and eradication program worldwide, thus it is important to define accuracy diagnostics assays and cut-off of those assays, due to variations from country to country and even among specific areas in the country. The variation of cutoff values depended on: prevalence of disease, vaccination status, animal management, and control and eradication programs. Therefore, a cut-off for the diagnosis of bovine brucellosis through fluorescence polarization assay (FPA) in Carchi—Ecuador was determined. The survey has been carried out in Carchi province of Ecuador, who is considered a province of high prevalence of brucellosis and the vaccination status is unknown due to the lack of registers. Sera samples (n = 200) were obtained from individual cows from randomly selected herds. Blood sera were tested through Fluoresce Polarization Assay (FPA) and competitive enzyme-linked inmunosorbent assay (cELISA) as confirmatory test, and then receiver operating characteristic (ROC) analysis was done. The sensitivity and specificity values of FPA were 88.7% and 92.50% respectively using a cut-off of 89.90 mP. Moreover, the area under the curve showed that 92.2% is the probability accuracy of the test. The advantage of the FPA is that it is a test with good characteristics of sensitivity and specificity as well as a simple and quick test.

关键词： Brucella Diagnosis Fluorescence Polarization Sensitivity Specificity

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Integrated Off-Line Ballast for High Brightness LEDs with Dimming Capability

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Circuits and Systems 2011年第4期2卷 338-351页

作者： Jorge garcia Antonio J. Calleja Emilio L. Corominas david Gacio Lidia Campa Ramón E. Díaz 不详

This paper presents an off-line integrated full ballast to supply a 35W assembly of Power LEDs. The proposed solution integrates an input PFC stage (a flyback converter operating in DCM) and a DC-DC output converter (a buck converter) into a single switch power stage, operating with peak current control. As it will be shown, this control scheme maintains the current through the load constant, regardless of the instantaneous value of the DC link voltage. This issue allows the use of a small capacitor for the DC link, which enhances the overall system reliability. The complete ballast has full dimming capability, and all the analysis and design steps are presented, thus ensuring the fulfilling of the existing regulations. The novelty of the final solution comes from the simplicity and robustness of the control scheme in an integrated compact single-switch power stage. A final prototype of the ballast has been built and tested, and experimental results are shown in the last part of the paper. Finally, conclusions and future developments are shown.

关键词： High Brightness LEDs Light Dimming Electrolytic Capacitor Avoidance Integration of Stages

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Amphibians and Reptiles of Luzon Island,V:The Herpetofauna of Angat Dam Watershed,Bulacan Province,Luzon Island,Philippines

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Asian Herpetological Research 2011年第4期2卷 177-198页

作者： david S.MCLEOD Cameron D.SILER Arvin C.DIESMOS Mae L.DIESMOS Vhon S.garcia Angela O.ARKONCEO Kelvin L.BALAQUIT Charlene C.UY Mariden M.VILLASERAN Earle C.YARRA Rafe M.BROWN Natural History Museum and Biodiversity Research Center Department of Ecology and Evolutionary BiologyUniversity of Kansas LawrenceKS 66045-7561USA Herpetology Section Zoology DivisionPhilippine National MuseumRizal ParkBurgos St.Ermita 1000ManilaPhilippines University of Santo Tomas Espana BoulevardSampaloc 1015ManilaPhilippines

We report amphibian and reptile distribution records based on recent biodiversity surveys conducted at the Angat Watershed Reservation, Bulacan Province, Luzon Island, Philippines. This watershed constitutes the principal water source for Manila, the Philippines＇ largest metropolitan area. As virtually nothing is known of the herpetological diversity of the immediate area and the surrounding Bulacan Province, all species recorded as part of our surveys constitute major geographical records and/or significant range extensions. Our data result in a total of 63 new records of amphibian （19 frogs） and reptile （22 lizards, 2 turtles, and 20 snakes） species for this protected area （and immediate vicinity） that serves as a watershed for the major metropolitan area of Manila and surrounding cities. Together with the few previous literature records, our new records bring the total number of amphibian and reptile species for Bulacan Province to 68. We discuss several strategies for future survey work （focusing on habitat type, seasonal variation, and elevational variability） that we anticipate will result in increased knowledge of diversity within the Angat Watershed Reserve. The impressive level of herpetological diversity within such a small area, so close to Metro Manila, emphasizes that the diversity and distribution patterns of amphibians and reptiles from Luzon are still poorly known and in need of further study.

关键词： amphibians Anagat Dam diversity Philippines reptiles

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Current role in facial allograft transplantation:what have we learned?

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Plastic and Aesthetic Research 2016年第1期3卷 211-218页

作者： Pedro Infante-Cossio Fernando Barrera-Pulido Tomas Gomez-Cia Domingo Sicilia-Castro Alberto garcia-Perla-garcia Purificacion Gacto-Sanchez Jose Maria Hernandez-Guisado Araceli Lagares-Borrego Rocio Narros-Gimenez Juan-david Gonzalez-Padilla Department of Oral and Maxillofacial Surgery Virgen del Rocio University Hospital41013 SevilleSpain Department of Plastic and Reconstructive Surgery Virgen del Rocio University Hospital41013 SevilleSpain

Face transplant(FT)has evolved enormously in the last 10 years since the successful completion of the first facial *** procedure has become a new reconstructive option for complex facial deformities to restore the anatomy of patients with severely disfigured *** authors review the literature and discuss the main surgical,immunological,and ethical aspects as well as the results described in patients undergoing *** date there have been more than thirty FT *** main indication was post-traumatic *** all cases a standard immunosuppression was performed with three drugs,although acute rejection episodes were observed,that could be controlled with conventional immunosuppressive ***,functional and aesthetic results have been excellent at short-term and high satisfaction rate exceeded initial expectations,although long-term data are still *** complications were opportunistic *** deaths that occurred have reopened the ethical debate about the potential complications and concerns of providing informed consent to *** progresses in microsurgical techniques and preoperative planning have promoted the evolution from partial to full *** these are on the basis of accurate and careful selection of well-motivated *** next challenge will be getting new immunosuppressive treatment *** clinical experience has demonstrated the FT viability,it is still considered an experimental procedure in which we have much to learn to define its true role in the current reconstructive surgery and resolve major technical,medical and ethical problems involved.

关键词： Face transplantation composite tissue transplantation facial allograft transplantation facial reconstruction outcomes and complications of face transplantation

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High-Impact Bug Report Identification with Imbalanced Learning Strategies

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Journal of Computer Science & Technology 2017年第1期32卷 181-198页

作者： Xin-Li Yang david Lo Xin Xia Qiao Huang Jian-Ling Sun College of Computer Science and Technology Zhejiang University Hangzhou 310027 China School of Information Systems Singapore Management University Singapore Singapore

In practice, some bugs have more impact than others and thus deserve more immediate attention. Due to tight schedule and limited human resources, developers may not have enough time to inspect all bugs. Thus, they often concentrate on bugs that are highly impactful. In the literature, high-impact bugs are used to refer to the bugs which appear at unexpected time or locations and bring more unexpected effects （i.e., surprise bugs）, or break pre-existing functionalities and destroy the user experience （i.e., breakage bugs）. Unfortunately, identifying high-impact bugs from thousands of bug reports in a bug tracking system is not an easy feat. Thus, an automated technique that can identify high-impact bug reports can help developers to be aware of them early, rectify them quickly, and minimize the damages they cause. Considering that only a small proportion of bugs are high-impact bugs, the identification of high-impact bug reports is a difficult task. In this paper, we propose an approach to identify high-impact bug reports by leveraging imbalanced learning strategies. We investigate the effectiveness of various variants, each of which combines one particular imbalanced learning strategy and one particular classification algorithm. In particular, we choose four widely used strategies for dealing with imbalanced data and four state-of-the-art text classification algorithms to conduct experiments on four datasets from four different open source projects. We mainly perform an analytical study on two types of high-impact bugs, i.e., surprise bugs and breakage bugs. The results show that different variants have different performances, and the best performing variants SMOTE （synthetic minority over-sampling technique）＋ KNN （K-nearest neighbours） for surprise bug identification and RUS （random under-sampling）＋ NB （naive Bayes） for breakage bug identification outperform the Fl-scores of the two state-of-the-art approaches by Thung et al. and garcia and Shihab.

关键词： high-impact bug imbalanced learning bug report identification

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Numerical Model of Ultra-High Molecular Weight Polyethylene Abrasive Wear Tests

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Modeling and Numerical Simulation of Material Science 2020年第1期10卷 1-14页

作者： Tomas De la Mora Ramirez Isaias Hilerio Cruz Marco Antonio Donu Ruiz Noe Lopez Perrusquia david garcia Bustos Martin Flores Martinez Autonomous Metropolitan University Azcapotzalco UnitAzcapotzalcoMexico CityMexico Science and Engineering of Materials Technological of Studies of JocotitlanJocotitlan State of MexicoMexico Group of Materials Science and Engineering Polytechnic University of the Valley of MexicoTultitlanMariano EscobedoMexico University of Guadalajara University Center of Exact Sciences and EngineeringGuadalajaraMéxico

Ultra-high molecular weight polyethylene (UHMWPE) has been used in orthopedics as one of the materials for artificial joints in knee, hip and spine prostheses, most of the implanted joints are designed so that the metal of the prosthesis is articulate against a polymeric material, however the main problems is the average life time of the UHMWPE due to wear, and the particles generated by the friction of the metal on the articulation of the polymer are the most common inducer of osteolysis, generating a loosening of the implant leading to an imminent failure resulting in the total replacement of the prosthesis. In this investigation a numerical model of abrasive wear was made using the classic Archard wear equation applied to dynamic simulation of finite element analysis (FEA) of the micro-abrasion test using a subroutine written in Fortran language linked to the finite element software to predict the rate of wear. The results of the numerical model were compared with tests of abrasive wear in the laboratory, obtaining a margin of error below 5%,concluding that the numerical model is feasible for the prediction of the rate of wear and could be applied in knowing the life cycle of joint prostheses or for the tribological analysis in industrial machinery or cutting tools. The wear coefficient (K) was obtained from the grinding tests depending on the depth of stroke of the crater, which was analyzed by 3D profilometry to obtain the wear rate and the wear constant.

关键词： Abrasive Wear Finite Element Numerical Wear Model UHMWPE

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Uncovering the genetic diversity of Giardia intestinalis in isolates from outbreaks in New Zealand

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Infectious Diseases of Poverty 2022年第3期11卷 27-36页

作者： Paul Ogbuigwe Patrick J.Biggs Juan Carlos garcia-Ramirez Matthew A.Knox Anthony Pita Niluka Velathanthiri Nigel P.French david T.S.Hayman School of Veterinary Science Massey UniversityPalmerston NorthManawatu-WanganuiNew Zealand School of Natural Sciences Massey UniversityPalmerston NorthManawatu-WanganuiNew Zealand

Background:Giardia intestinalis is one of the most common causes of diarrhoea worldwide. Molecular techniques have greatly improved our understanding of the taxonomy and epidemiology of this parasite. Co-infection with mixed (sub-) assemblages has been reported, however, Sanger sequencing is sometimes unable to identify shared subtypes between samples involved in the same epidemiologically linked event, due to samples showing multiple dominant subtypes within the same outbreak. Here, we aimed to use a metabarcoding approach to uncover the genetic diversity within samples from sporadic and outbreak cases of giardiasis to characterise the subtype diversity, and determine if there are common sequences shared by epidemiologically linked cases that are missed by Sanger ***:We built a database with 1109 unique glutamate dehydrogenase (gdh) locus sequences covering most of the assemblages of G. intestinalis and used gdh metabarcoding to analyse 16 samples from sporadic and outbreak cases of giardiasis that occurred in New Zealand between 2010 and ***:There is considerable diversity of subtypes of G. intestinalis present in each sample. The utilisation of metabarcoding enabled the identification of shared subtypes between samples from the same outbreak. Multiple variants were identified in 13 of 16 samples, with Assemblage B variants most common, and Assemblages E and A present in mixed ***:This study showed that G. intestinalis infections in humans are frequently mixed, with multiple subtypes present in each host. Shared sequences among epidemiologically linked cases not identified through Sanger sequencing were detected. Considering the variation in symptoms observed in cases of giardiasis, and the potential link between symptoms and (sub-) assemblages, the frequency of mixed infections could have implications for our understanding of host–pathogen interactions.

关键词： DNA sequencing Epidemiology Genetic diversity Giardiasis Metabarcoding

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喷涂胶结内衬修复后的腐蚀金属管道强度测试

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非开挖技术 2014年第6期 53-57页

作者： david Becerril garcia Ian D.Moore 邬明皓

通过喷涂胶结内衬的方法对埋于皇后大学地球工程实验室西侧试验坑的两根直径1．2m且底部（invert）被强烈腐蚀的金属管道进行了修复。在金属管道以及内部的衬板均装置有线性电位器（1inear poten-tiometers），传统应变传感器以及光纤... 详细信息

通过喷涂胶结内衬的方法对埋于皇后大学地球工程实验室西侧试验坑的两根直径1．2m且底部（invert）被强烈腐蚀的金属管道进行了修复。在金属管道以及内部的衬板均装置有线性电位器（1inear poten-tiometers），传统应变传感器以及光纤应变传感器用于测量管道直径的变化。并分别在1．2m与2．1m的埋深下利用标准单轴和平衡悬架轴加载的方法对管道在工作荷载下的性能做了评估。之后在1．2m埋深下利用平衡悬架轴加载对管道的最大极限状态进行了测试。将管道从地底挖掘出后，观测了修复后的厚度剖面。本文简要说明了本次修复对管道在工作载荷下的变形与曲率产生的影响。之后对最大极限状态（包括裂纹的分布和抗表面载荷能力）进行了描述。本次试验所得结论已考虑加载过程中圆周弯矩和内衬裂纹的影响。

关键词：喷涂胶结内衬技术管道修复强度测试

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