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Advances in Biological Chemistry 2017年第2期7卷 122-138页

作者： luis raúl gutiérrez-lucas luz María Chávez-ramírez leticia Arregui Departamento de Ciencias Naturales DCNI Universidad Aut&oacute noma Metropolitana Unidad Cuajimalpa M&eacute xico City M&eacute xico Secretarí a de Salud Centro de Salud TI Memetla M&eacute xico City M&eacute xico

The Desierto de los leones National Park is a place that features recreational activities for residents and visitors to Mexico City. The Presa de los Patos (Ducks Dam) is one of the many bodies of water that are present in the park. By means of physico-chemical and microbiological analysis, it was determined that the water of the Presa de los Patos cannot be considered potable. The pH range was between 5.5 - 5.9. The turbidity exceeded the values established in the standards (10.7 - 32.3 Nephelometric Turbidity Units (NTU’s)). Chemical Oxygen Demand (COD) showed that large amounts of oxygen are needed to oxidize organic matter (106 - 450 mg/l). The amount of coliforms and fecal coliforms exceeds the values established by the standards used (total coliforms 98 - 956 Colony Forming Units (CFU’s), fecal coliforms 78 - 807 CFU’s). Five bacterial genera (Escherichia coli, Pseudomona, Klebsiella, Shigella and Salmonella) were isolated and identified. Most of the bacteria isolated were resistant to ampicillin (90%), while 25% were resistant to ciprofloxacin. The water consumption of the Presa de los Patos is a great risk for the habitants and visitors of the park.

关键词： Water Physico-Chemical Microbiological Antimicrobial Resistance Antibiotics

Bioinformatics Analysis of NprR-NprX Quorum-Sensing System of <i>Bacillus thuringiensis</i>Isolates from the Papaloapan Region, Oaxaca-Mexico

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Advances in Biological Chemistry 2015年第7期5卷 293-304页

作者： Humberto rafael Bravo-D Alain Cruz-Nolasco luis raúl gutiérrez-lucas Ana Karin Navarro-Mtz División de Estudios de Posgrado Universidad del Papaloapan Circuito Central 200 Parque Industrial Tuxtepec Oaxaca México Instituto de Biotecnología Universidad del Papaloapan Circuito Central 200 Parque Industrial Tuxtepec Oaxaca México

Quorum sensing is a chemical communication process that bacteria use to regulate collective behaviors. In Gram-positive bacteria, oligopeptides (called autoinducers) are the signaling molecules to elicit quorum sensing. In Bacillus thuringiensis, NprR is a transcriptional regulator whose activity depends on the NprX signalling peptide. Bacillus thuringiensis is closely related to Bacillus cereus and Bacillus anthracis. The principal difference between them is that Bacillus thuringiensis is the only one that produced Cry protein. The aim of this study is to explore the relation of nprR and 16S rRNA genes in Bacillus thurin-giensis. Phylogenetic trees of nucleotide sequences of nprR and 16S rRNA genes were built. Sequences of fourteen new isolates from Papaloapan region were included in those phylo-genetic trees. In order to identify the isolates, a simple and fast methodology considering the Cry protein formation was used. The 16S rRNA phylogenetic tree allows identify eight isolates as Bacillus thuringiensis and the others as Bacillus spp. The nprR phylogenetic tree does not match with the 16S rRNA phylogenetic tree. This confirms that nprR is not a molecular marker for evolution. Most of the new isolates have the same NprR sequence (WTSDIVG). However, the SKPDIVG is the most common NprR sequence in thuringiensis species.

关键词： Quorum-Sensing Bacillus thuringiensis NprR-NprX Phylogenetic Tree

Strategies for the Extraction, Purification and Amplification of Metagenomic DNA from Soil Growing Sugarcane

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Advances in Biological Chemistry 2014年第4期4卷 281-289页

作者： luis raúl gutiérrez-lucas Juan José Montor-Antonio Nohemí Gabriela Cortés-lópez Sandra del Moral División de Estudios de Posgrado Universidad del Papaloapan Tuxtepec México Instituto de Biotecnología. Universidad del Papaloapan Tuxtepec Oaxaca México

Recently, studies were initiated to investigate the metagenome, which represents the genomes of cultured and uncultured microbes, as a rich source for isolation of many novel genes. The meta-genomic approach originated from the molecular analysis of microbial communities, which revealed that the majority of microorganisms in nature were not cultivable by standard culturing techniques. Therefore, most microorganisms in nature have not been characterized. Although numerous methods have been reported for direct DNA isolation and purification from microorganisms in soil, the sample preparation procedures and experimental conditions used in different studies vary widely. Soils are therefore one of the most challenging environmental matrices from which to obtain microbial DNA that will support PCR. The Papaloapan River is the second largest river basin in México. For the climatic conditions of this region, there is great diversity in plants, animals and microorganisms. In the Papaloapan region different fruits are grown, however, the main crops are sugarcane and pineapple. In this work the extraction of DNA from soils of sugarcane cultivation was performed. We used PCR tests to assess the quality of DNA extracted from soil by amplifying the 16S rDNA gene. Changes in both protocols were performed;satisfactory results were obtained as to the quality of DNA and gene amplification. These results will allow continuing the metagenomic studies, such as sequencing, library construction and identification of enzymes cellulase and amylase activity. It is the first time these studies were performed in the Papaloapan region.

关键词： Metagenomic Soil DNA Metagenome Papaloapan Basin

Identification of the autotransporter Pet toxin in Proteus mirabilis strain isolated from patients with urinary tract infections

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Advances in Biological Chemistry 2012年第3期2卷 283-290页

作者： luis raúl gutiérrez-lucas Guillermo Mendoza-Hernández Bertha González-Pedrajo Carlos Eslava-Campos Jaime Bustos-Martínez Teresita Sainz-Espunes Departamento de Sistemas Biológicos Universidad Autónoma Metropolitana-XochimilcoMéxico CityMéxico Departamento de Bioquímica Facultad de MedicinaUNAMMéxico CityMéxico Instituto de Fisiología Celular UNAMMéxico CityMéxico Departamento de Atención a la Salud Universidad Autónoma Metropolitana-XochimilcoMéxico CityMéxico

Proteus mirabilis, a motile Gram-negative bacterium, represents a common cause of complicated urinary tract infections. Autotransporters are a family of secreted proteins from Gram-negative bacteria that direct their own secretion across the outer membrane (type V autotransporter secretion mechanism). Serine protease autotransporters of Enterobacteriaceae (SPATEs) include adhesins, toxins, and proteases that can contribute to the virulence. Plasmid-encoded toxin (Pet) is the predominant protein in culture supernatants of enteroaggregative E. coli prototype strain 042 and has been extensively studied. Pet toxin is encoded on the 65-MDa adherence-related plasmid of EAEC 042 strain. In this work, Pet protein was found in the supernatant obtained from Proteus mirabilis RTX339 strain isolated from a psychiatric patient suffering complicated urinary tract infections (UTIs). The nucleotide sequence of pet gene was obtained using primers designed from E. coli 042 pet gene reported. The alignment of the sequence showed 100% identity with the pet gene reported. Is important to note that Proteus mirabilis RTX339 pet gene has chromosomal location. The chromosomal location of the gene was established since no plasmids were harbored by this strain.

关键词： Pet Proteus mirabilis SPATEs

Microsurgical management of radicular cyst using guided tissue regeneration technique:A case report

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World Journal of Clinical Cases 2024年第7期12卷 1346-1355页

作者： Juan Carlos Gómez Mireles Eugenia Karina Martínez Carrillo Katia Alcalá Barbosa Evangelina gutiérrez Cortés Javier González ramos luis Antonio González Gómez Rubén Alberto Bayardo González Sarah Monserrat lomelí Martínez Periodontics Specialty Department of Integral Dentistry ClinicsCentro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajara 44340Mexico Endodontics Specialty Department of Integral Dentistry ClinicsCentro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajara 44340Mexico Endodontics Specialty Department of ClinicsCentro Universitario de Los AltosUniversidad de GuadalajaraTepatitlán de Morelos 47620Mexico Specialty in Oral Pathology Surgical-Stomatological DepartmentAutonomous University of GuadalajaraZapopan 45129Mexico Independent Researcher Guadalajara 44340Mexico Department of Integral Dentistry Clinics Centro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajara 44340Mexico Department of Medical and life Sciences Centro Universitario de la CiénegaUniversidad de GuadalajaraOcotlán 47810Mexico Master of Public Health Department of Well-being and Sustainable DevelopmentCentro Universitario del NorteUniversidad de GuadalajaraColotlán 46200Mexico

BACKGROUND radicular cyst is a lesion of odontogenic origin that arises from epithelial remains due to periapical periodontitis caused by inflammatory reactions generated at the apex of affected teeth with infected or necrotic *** therapeutic mana gement of radicular cysts is *** is only one case report of enucleation of a radicular cyst managed with microsurgery and apicoectomy,but without the use of the guided tissue regeneration(GTR)technique in the same surgical *** present clinical case describes the management of a radicular cyst with microsurgical approach,performance of an apicoectomy of the tooth associated with the entity,application of GTR technique,use of a resorbable membrane of type I bovine collagen,and bovine *** SUMMARY A 68-year-old patient presented with a radicular cyst from an upper lateral *** microsurgical management used was aimed at enucleating the chemical membrane,performing apicoectomy of the tooth along with careful and precise retrograde filling,and implementing GTR technique using a resorbable collagen membrane and bovine *** diagnosis of radicular cyst was confirmed using histopathological *** patient underwent follow-up evaluations at 10 and 30 d *** 4 months postoperative evaluation,she remained asymptomatic,and radiographs showed significant periapical healing with adequate bone *** These results suggest that microsurgical management using the GTR technique with collagen membrane and xenograft,contributes to bone regeneration.

关键词： Odontogenic cysts Apical periodontal cyst Dental root end cyst Case report

A novel heterozygous SF1/NR5A1 gene variant causes 46,XY DSD-gonadal dysgenesis with hypergonadotropic hypogonadism without adrenal insufficiency

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Genes & Diseases 2024年第4期11卷 128-130页

作者： luis ramos Department of Reproductive Biology Instituto Nacional de Ciencias Medicas y Nutricion Salvador ZubirdnTlalpanMexico City 14080Mexico

Steroidogenic factor 1(SF1/NR5A1;nuclear receptor subfamily 5 group A member 1)is an essential orphan protein involved in gonadal embryogenesis,sex determination,and reproductive endocrinology.

关键词： insufficiency determination gonadal

A cleaner production strategy for acid mine drainage prevention of waste rock:A porphyry copper case

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International Journal of Mining Science and Technology 2024年第8期34卷 1163-1177页

作者： Yesica l.Botero Isabelle Demers luis A.Cisternas ArnoldoÁvila Mostafa Benzaazoua Departamento de Ingeniería Química y Procesos de Minerales Universidad de AntofagastaAntofagasta1240000Chile Research Institute on Mines and Environment Universitédu Québec en Abitibi-TémiscamingueRouyn-NorandaQC J9X5E4Canada Eriez Flotation Group Chile S.A. Santiago1240000Chile Geology and Sustainable Mining Institute University Mohammed Ⅵ PolytechnicLot 660 Hay Moulay RachidBen Guerir 43150Morocco

An in-process technology approach is proposed to identify the source of acid mine drainage(AMD)generation and prevent its formation in a porphyry copper waste rock(WR).Adopting actions before stockpiling the WR enables the establishment of potential contaminants and predicts the more convenient method for AMD prevention.A WR sample was separated into size fractions,and the WR’s net acidgenerating potential was quantified using chemical and mineralogical *** diameter of physical locking of sulfides(DPlS)was determined,and the fractions below the DPlS were desulfurized using ***,the WR fractions and tailing from the flotation test were submitted to acid-base accounting and weathering tests to evaluate their acid-generating *** show that the WR’s main sulfide mineral is pyrite,and the DPlS was defined as 850μm.A sulfide recovery of 91%was achieved using a combination of HydroFloat^(®)and Denver cells for a size fraction lower than *** grinding was *** results show that size fractions greater than DPlS and the desulfurized WR are unlikely to produce *** outcomes show that in-processing technology can be a more proactive approach and an effective tool for avoiding AMD in a porphyry copper WR.

关键词： Waste rock Porphyry copper ore Desulfurization Acid mine drainage HydroFloat^(®) In-process technology Cleaner production

Measuring Impact of lean Manufacturing Tools for Continuous Improvement on Economic Sustainability

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 452-474页

作者： luis Javier Márquez Figueroa Jorge luis García-Alcaraz Ahmed I.Osman Alfonso Jesús Gil lópez Yashar Aryanfar Mika Sillanpää Mamdouh El Haj Assad Department of Electrical Engineering and Computer Science Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico Department of Industrial Engineering and Manufacturing Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico School of Chemistry and Chemical Engineering Queens UniversityBelfastNorthern IrelandUK Department of Economic and Managerial Sciences University of La RiojaLa RiojaSpain Department of Chemical Engineering University of JohannesburgJohannesburgSouth Africa Department of Sustainable and Renewable Energy Engineering University of SharjahSharjahUAE

Using lean Manufacturing(lM)tools in production processes is crucial for companies’economic,environmental,and social sustainability *** study shows a structural equation model(SEM)that shows the relationship between lM Tools like Kaizen(KAI),Gemba(GEM),Value Stream Mapping(VSM)and Key Performance Indicator(KPI)with Economic Sustainability(ECS).Seven hypotheses were evaluated with data from 179 responses to a questionnaire about the Mexican maquiladora industry,showing that these variables are *** a 95%confidence level,the model was evaluated using the partial least squares *** findings indicate that the relationships between KAI and GEM and KAI and VSM have the strongest relationship,followed by VSM and ECS;however,VSM has the strongest effect on *** on these findings,it is recommended that managers adopt a continuous improvement(KAI)approach based on working directly on the shop floor(GEM and VSM)to support their decisions regarding economic growth(ECS).

关键词： lean manufacturing economic sustainability structural equation model quality improvement

Online Demand Response Characterization Based on Variability in Customer Behavior

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 936-946页

作者： lester Marrero Daniel Sbárbaro luis García-Santander the Department of Electrical Engineering University of ConcepciónConcepción 4070409Chile

This paper proposes an online framework to characterize demand response(DR)over *** proposed framework facilitates obtaining and updating the daily consumption patterns of *** essential concept of response profile class(RPC)is introduced for characterization and complemented by the measure of the variability in customer *** paper uses a modified version of the incremental clustering by fast search and find of density peaks(CFSFDP)algorithm for daily profiles,considering the multivariate normal kernel density estimator and incremental forms of the Davies-Bouldin(i DB)and Xie-Beni(i XB)validity *** studies conducted using real-world and simulated daily profiles of residential and commercial Chilean end-users have demonstrated how the proposed framework can continuously characterize *** proposed framework is proven to achieve realistic customer models for effective energy management by estimating the customer response to price signals at the distribution system operator(DSO)level.

关键词： Demand response(DR) incremental indice online characterization online clustering response profile class(RPC)

Optimal Design of Hybrid Microgrid in Isolated Communities of Ecuador

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 488-499页

作者： luis A.Pesantes Ruben Hidalgo-león Johnny Rengifo Miguel Torres Jorge Aragundi JoséCordova-Garcia luis F.Ugarte Facultad de Ingeniería en Electricidad y Computación of Escuela Superior Politécnica del litoral(ESPOl)University GuayaquilEcuador Department of Electrical Engineering at Universidad Técnica Federico Santa María SantiagoChile IEEE

In rural territories, the communities use energy sources based on fossil fuels to supply themselves with electricity, which may address two main problems: greenhouse gas emissions and high fuel prices. Hence, there is an opportunity to include renewable resources in the energy mix. This paper develops an optimization model to determine the optimal sizing, the total annual investment cost in renewable generation, and other operating costs of the components of a hybrid microgrid. By running a k-means clustering algorithm on a meteorological dataset of the community under study, the hourly representative values become input parameters in the proposed optimization model. The method for the optimal design of hybrid microgrid is analyzed in six operating scenarios considering:(1) 24-hour continuous power supply;(2) load shedding percentage;(3) diesel power generator(genset) curtailment;(4) the worst meteorological conditions;(5) the use of renewable energy sources including battery energy storage systems(BESSs);and(6) the use of genset. A mathematical programming language(AMPl) tool is used to find solutions of the proposed optimization model. Results show that the total costs of microgrid in the scenarios that cover 100% of the load demand(without considering the scenario with 100% renewables) increase by over 16% compared with the scenario with genset operation limitation. For the designs with power supply restrictions, the total cost of microgrid in the scenario with load shedding is reduced by over 27% compared with that without load shedding.

关键词： Battery energy storage system(BESS) isolated community microgrid renewable energy optimization