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Wyszukujesz frazę "Rodríguez, Carlos" wg kryterium: Autor


Tytuł:
Matices del entorno pandémico: Covidianidad, polarización y vulnerabilidad social
Nuances do ambiente pandêmico: covidância, polarizaçao e vulnerabilidade social
Autorzy:
Rodríguez Arechavaleta, Carlos Manuel
Powiązania:
https://bibliotekanauki.pl/articles/2131604.pdf
Data publikacji:
2022-06-30
Wydawca:
Uniwersytet Warszawski. Wydawnictwa Uniwersytetu Warszawskiego
Tematy:
COVID-19
covidianity
polarization
social trust
social vulnerability
covidianidad
polarización
confianza social
vulnerabilidad social
Opis:
El artículo aborda la complejidad del impacto pandémico en contextos de alta incertidumbre estructural, déficits institucionales y vulnerabilidad social. Basado en una amplia revisión bibliográfica, el argumento tiene como premisa el carácter público y letal de las pandemias y su naturaleza implosiva sobre los estándares básicos de la vida social, las prácticas de carácter rutinarias o reflexivas, las cosmovisiones, las creencias, así como las formas históricas de interacción, asociación y de acción colectiva de una determinada comunidad. Además, pone en el centro de atención la capacidad de respuesta de los gobiernos al COVID-19, sus trayectorias de políticas sanitarias y la cultura cívica de la sociedad. Recupera la noción de confianza social, tanto horizontal entre ciudadanos, como vertical entre estos y gobierno, componente clave en la construcción de capital de acción colectiva para ampliar el paquete de opciones de respuestas a la pandemia, reconociendo el reto comunicativo. Finalmente, subraya que, en estos entornos, la crisis pandémica reta los cimientos mínimos de equidad y justicia social.
O artigo aborda a complexidade do impacto da pandemia em contextos de alta incerteza estrutural, déficits institucionais e vulnerabilidade social. Baseado em uma extensa revisao bibliográfica, e projectado para a regiao da América Latina, parte do carácter público e letal das pandemias e sua natureza implosiva sobre os padroes básicos de vida social, prácticas rotineiras ou reflexivas, visoes de mundo, crenças, bem como o histórico formas de interaçao, associaçao e açao colectiva de uma determinada comunidade. Além disso, coloca no centro das atençoes a capacidade de resposta dos governos ao COVID-19, suas trajetórias de políticas de saúde e a cultura cívica da sociedade. Resgata a noçao de confiança social, tanto horizontalmente entre cidadaos quanto verticalmente entre governo e cidadaos, como componente fundamental na construçao do capital de açao coletiva para ampliar o pacote de opçoes de respostas à pandemia, reconhecendo o desafio da eqüidade e justiça social.      
The article addresses the complexity of the pandemic impact in contexts of high structural uncertainty, institutional deficits and social vulnerability. Based on an extensive bibliographic review, and designed for the Latin American region, part of the public and lethal nature of pandemics and their implosive nature on the basic standards of social life, routine or reflective practices, worldviews, beliefs, as well as the historical forms of interaction, association and collective action of a certain community. In addition, the response capacity of governments to COVID-19 is exposed to the center of attention, their health policy trajectories and the civic culture of society. It recovers the notion of social trust, both horizontally between citizens and vertical between government and citizens, as a key component in the construction of collective action capital to expand the package of options for responses to the pandemic, recognizing the communication challenge. Finally, it underlines that in these settings the pandemic crisis challenges the minimum foundations of equity and social justice.
Źródło:
Revista del CESLA. International Latin American Studies Review; 2022, 29; 123-138
1641-4713
Pojawia się w:
Revista del CESLA. International Latin American Studies Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Event-based feedforward control of linear systems with input time-delay
Autorzy:
Rodríguez, Carlos
Aranda-Escolástico, Ernesto
Guinaldo, Maria
Guzmán, José Luis
Dormido, Sebastián
Powiązania:
https://bibliotekanauki.pl/articles/330326.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
time delay system
linear system
process control
control system design
układ z opóźnieniem
układ liniowy
sterowanie procesem
układ regulacji
Opis:
This paper proposes a new method for the analysis of continuous and periodic event-based state-feedback plus static feedforward controllers that regulate linear time invariant systems with time delays. Measurable disturbances are used in both the control law and triggering condition to provide better disturbance attenuation. Asymptotic stability and L2-gain disturbance rejection problems are addressed by means of Lyapunov–Krasovskii functionals, leading to performance conditions that are expressed in terms of linear matrix inequalities. The proposed controller offers better disturbance rejection and a reduction in the number of transmissions with respect to other robust event-triggered controllers in the literature.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2019, 29, 3; 541-553
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Al Khudairah Necropolis (Sharjah, UAE): Reflections from the 2023 Field Season
Autorzy:
del Cerro Linares, Carmen
Fernández Rodríguez, Carlos
Gómez Sanz, Paula
Alonso García, Alicia
González Martín, Armando
Powiązania:
https://bibliotekanauki.pl/articles/28763082.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Instytut Kultur Śródziemnomorskich i Orientalnych PAN
Tematy:
al Khudairah
Sharjah
necropolis
burial mound
anthropological studies
Opis:
The necropolis from Jebel al Khudairah, located in the Central Region of the Emirate of Sharjah (United Arab Emirates) witnessed excavations in 2020 and 2023 from members of the Spanish Archaeological and Archaeobiological Mission at Sharjah, drawn from Universidad Autónoma de Madrid. In this paper we present a preliminary overview of the results from these two field seasons after completing excavations of five tombs of very diverse types, located in several sectors of the jebel. Only one of them provided remains of burials of at least two individuals accompanied by a metal arrowhead. Nevertheless, the preliminary comparative analysis of the architecture of the structures as well as of the only datable find, allows one to make some suggestions concerning the chronological span of the necropolis.
Źródło:
Études et Travaux (Institut des Cultures Méditerranéennes et Orientales de l’Académie Polonaise des Sciences); 2023, 36; 39-56
2084-6762
2449-9579
Pojawia się w:
Études et Travaux (Institut des Cultures Méditerranéennes et Orientales de l’Académie Polonaise des Sciences)
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Is Uruguay More Resilient This Time? Distributional Impacts of a Crisis Similar to the 2001–02 Argentine Crisis
Autorzy:
Cabanillas, Oscar Barriga
Lugo, Maria Ana
Rodríguez-Castelan, Carlos
Nielsen, Hannah
Powiązania:
https://bibliotekanauki.pl/articles/565692.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Warszawski. Wydawnictwo Naukowe Wydziału Zarządzania
Tematy:
Business cycles
microsimulations
distributional analysis
Uruguay
Opis:
The 2001–02 Argentine crisis had a profound impact on Uruguay’s economy. Uruguay’s gross domestic product shrank by 17.5 percent, and the proportion of people living below the poverty line doubled in only two years. It took almost 10 years for the poverty rate to recover to its precrisis level. This paper uses a macro-micro simulation technique to simulate the impact of a similar crisis on the current Uruguayan economy. The simulation exercise suggests that Uruguay would now be in a better place to weather such a severe crisis. The impact on poverty would be considerably more moderate; inequality would not change significantly; and household incomes would be 8 percent lower than in the absence of a crisis (almost 9 percent lower among households in the bottom 40 percent of the income distribution). The paper also explores the changes in social welfare policy that took place in the last decade that are protecting vulnerable groups from new macroeconomic shocks. We find that, despite the new policies, young individuals, woman-headed households, residents of Montevideo, and people who have not completed secondary education are more vulnerable to falling into poverty were the crisis to strike.
Źródło:
Journal of Banking and Financial Economics; 2015, 2(4); 64-90
2353-6845
Pojawia się w:
Journal of Banking and Financial Economics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effective treatment of severe hypertensive crisis in 2-year-old child with neuroblastoma
Autorzy:
Raciborska, Anna
Bilska, Katarzyna
Antoniewicz, Jolanta
Rychłowska-Pruszyńska, Magdalena
Rodriguez-Galindo, Carlos
Fijałkowska, Anna
Powiązania:
https://bibliotekanauki.pl/articles/1065170.pdf
Data publikacji:
2015
Wydawca:
Medical Education
Tematy:
children
doxazosin
hypertensive crisis treatment
labetalol
neuroblastoma
Opis:
We describe a case of a 2-year-old boy with neuroblastoma and high catecholamine levels which developed a severe hypertensive crisis. An oral propranolol and oral angiotensin-converting enzyme inhibitor were used with a mild short transient benefit. However, an intravenous labetalol and oral doxazosin used for over 3 weeks resulted in successful blood pressure control. This report highlights the prolonged use of α and β-adrenergic antagonist therapy in children with neuroblastoma with refractory catecholamine-induced hypertension.
Źródło:
OncoReview; 2015, 5, 2; A53-56
2450-6125
Pojawia się w:
OncoReview
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Migration Coverage in Europe, Russia and the United States
Autorzy:
Kreutler, Marcus
Fengler, Susanne
Asadi, Nastaran
Bodrunova, Svetlana
Budivska, Halyna
Diop, Layire
Ertz, Georgia
Gigola, Daria
Katus, Eszter
Kovacs, Denisa
Kuś, Michał
Láb, Filip
Litvinenko, Anna
Mack, Johanna
Maier, Scott
Pinto Martinho, Ana
Matei, Antonia
Miller, Kaitlin C.
Oppermann, Lisa
Pérez Vara, Eva
Polyák, Gábor
Ravisankar, Rajeev
Rodríguez Pérez, Carlos
Semova, Dimitrina J.
Skleparis, Dimitris
Splendore, Sergio
Štefaniková, Sandra
Szynol, Adam
Telo, Décio
Zguri, Rrapo
Powiązania:
https://bibliotekanauki.pl/articles/2152496.pdf
Data publikacji:
2022-09-22
Wydawca:
Polskie Towarzystwo Komunikacji Społecznej
Tematy:
comparative analysis
journalism
migration
refugee
media coverage
Opis:
Six years after the so-called ‘refugee crisis’ in 2015, the European Union remains divided on questions of migration and asylum policy. The issue also remains high on the agendas of the USA and Russia, two other key destination countries with immigration from Latin America and the Post-Soviet space. This article presents results from a comparative study of news coverage in 17 countries, focusing on 10 EU member states in Western and Central Eastern Europe (CEE), the USA and Russia. The intensity of coverage was remarkably different, with Hungary’s and Germany’s media standing out while Russian media displayed relatively low levels of coverage. Individual migrants and refugees were most visible in the two outlets from the USA. Media in CEE countries tended towards a more critical approach than media in Western Europe. However, differences between most countries’ pairs of analyzed media outlets indicate a more pluralistic debate than frequently assumed.
Źródło:
Central European Journal of Communication; 2022, 15, 2(31); 202-226
1899-5101
Pojawia się w:
Central European Journal of Communication
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Using the instantaneous angular speed measurement to characterize the transient dynamic response of an inertial system
Autorzy:
Valencia, Andrés Felipe Rodríguez
Piedrahita, Carlos Alberto Romero
Powiązania:
https://bibliotekanauki.pl/articles/2096188.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
Tematy:
dynamic response
transient state
starter motor
instantaneous angular velocity
inertial system
odpowiedź dynamiczna
stan nieustalony
rozrusznik samochodowy
system inercyjny
Opis:
The measurement of instantaneous angular speed in flywheels has been used in Internal Combustion Engines for the diagnosis of faults in the fuel injection systems, combustion quality at idle, ignition system, and especially in the performance assessment of starter motor and battery accumulator, among others. It is the aim of this paper to forecast the use of an experimental flywheel-based test bench, driven by a single-cylinder Internal Combustion Engine and a starter motor, developed to perform research studies in the laboratory of internal combustion engines. It is illustrated the measurement and processing of the instantaneous angular speed of a flywheel to characterize the dynamic response of the inertial system during the run-up and run-out regimes. The mathematical model of the transfer function is presented, relating the angular velocity with the torque transmitted by the starter motor as a first-order system. For the acquisition of the signal, a NI 6009 card is used, while a Matlab computer program is employed to plot the instantaneous angular velocity curves, and also to identify the time response of the system. The time constant is 1.54 seconds, which corresponds to 63.2% of the value of steady state signal in run-up regime.
Źródło:
Diagnostyka; 2022, 23, 2; art. no. 2022204
1641-6414
2449-5220
Pojawia się w:
Diagnostyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Manufacture of Toughened Al2O3-Based Composites by the Combination of RBAO and SPS Processes
Autorzy:
Rocha-Rangel, Enrique
Calles-Arriaga, Carlos A.
López-Hernández, Juan
Rodríguez-García, José A.
Powiązania:
https://bibliotekanauki.pl/articles/2203745.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
RBAO process
SPS process
Al2O3
fracture toughness
ceramic composites
Opis:
The effect of additions of silver or titanium (0.5 or 3 vol.%) microparticles on the microstructure, as well as some physical properties of Al2O3-based composites, were studied. The processing method for the manufacturing of alumina-based composites was a combination of RBAO and SPS processes. After the SPS process, bodies with almost full density were obtained. Observations by optical microscopy show a very fine and homogenous microstructure in all samples. Concerning mechanical properties, the addition of metals on alumina increases its fracture toughness significantly (112% for the sample with additions of silver, while the composite with additions of titanium fracture toughness increases by 72%). In terms of optical properties, both silver and titanium improve the absorbance in the visible range.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 1; 249--255
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Approach to students’ social representations in the construction of academic European geography: A case study of Spanish university students
Autorzy:
Macía Arce, Xosé Carlos
Lois González, Rubén Camilo
Lestegás, Francisco Rodríguez
Armas Quintá, Francisco Xosé
Powiązania:
https://bibliotekanauki.pl/articles/1052584.pdf
Data publikacji:
2017-12-15
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
academic geography of Europe
teacher training for secondary education
social representations
test of word association
Opis:
This article provides the results of classroom research involving university students training to be secondary school teachers of geography and history. The research is based on the analysis of a word association test on Europe and the European Union. The results constitute an approach to the geographical and historical representations these students have of their own European continent. This is a fundamental question considering that this collective group is training to teach the contents and values of European geography in secondary school education. From here on, our intention is no other than to carry out an exercise of synthesis and overall reflection on the test results and introduce issues which could generate some debate in the educational community.
Źródło:
Quaestiones Geographicae; 2017, 36, 4; 159-169
0137-477X
2081-6383
Pojawia się w:
Quaestiones Geographicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A study of the Inverse Gaussian Process with hazard rate functions-based drifts applied to degradation modelling
Autorzy:
Rodríguez-Picón, Luis Alberto
Méndez-González, Luis Carlos
Pérez-Olguín, Iván JC
Hernández-Hernández, Jesús Israel
Powiązania:
https://bibliotekanauki.pl/articles/2175136.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
inverse Gaussian process
hazard rate function
degradation rate
variable drift
Opis:
The stochastic modelling of degradation processes requires different characteristics to be considered, such that it is possible to capture all the possible information about a phenomenon under study. An important characteristic is what is known as the drift in some stochastic processes; specifically, the drift allows to obtain information about the growth degradation rate of the characteristic of interest. In some phenomenon’s the growth rate cannot be considered as a constant parameter, which means that the rate may vary from trajectory to trajectory. Given this, it is important to study alternative strategies that allow to model this variation in the drift. In this paper, several hazard rate functions are integrated in the inverse Gaussian process to describe its drift in the aims of individually characterize degradation trajectories. The proposed modelling scheme is illustrated in two case studies, from which the best fitting model is selected via information criteria, a discussion of the flexibility of the proposed models is provided according to the obtained results.
Źródło:
Eksploatacja i Niezawodność; 2022, 24, 3; 590--602
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stochastic modelling of the temperature increase in metal stampings with multiple stress variables and random effects for reliability assessment
Ocena niezawodności z wykorzystaniem stochastycznego modelu wzrostu temperatury w metalowych wytłoczkach, uwzględniającego wielorakie zmienne naprężeniowe oraz efekty losowe
Autorzy:
Quezada del Villar, Andrea Viridiana
Rodríguez-Picón, Luis Alberto
Pérez-Olguín, Iván JC
Méndez-González, Luis Carlos
Powiązania:
https://bibliotekanauki.pl/articles/301832.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
accelerated degradation test
gamma process
random effect
reliability assessment
badanie przyspieszonego starzenia
proces gamma
efekty losowe
ocena niezawodności
Opis:
Many products wear out over time even before they fail or stop working, therefore, through accelerated degradation tests one is able to make inferences about statistical parameters or the distributions of a product useful life. Since many devices experience different types of variation due to unobservable factors during the manufacturing processes or under certain operating conditions; these situations lead to the need in developing accelerated degradation models with several variables of acceleration and random effects. The proposed model in this paper, is a model based on the gamma process with random effects to have a better analysis of degradation. This model is applied to the analysis of the temperature increase of metal stampings that are affected by multiple explanatory variables. In addition, a statistical inference method based on a Bayesian approach is used to estimate the unknown parameters to then perform a reliability analysis after obtaining the first-passage time distributions.
Wiele produktów zużywa się z upływem czasu zanim nawet ulegną uszkodzeniu lub przestaną działać. Badania przyspieszonego starzenia pozwalają wyciągać wnioski na temat parametrów statystycznych lub rozkładów okresu użytkowania produktu. Wiele urządzeń podlega różnym rodzajom zmienności pod wpływem działania nieobserwowalnych czynników występujących podczas procesu produkcyjnego lub w pewnych warunkach pracy; sytuacje te wymagają opracowania modeli przyspieszonego starzenia uwzględniających wielorakie zmienne przyspieszenia oraz efekty losowe. Zaproponowany w przedstawionym artykule model opiera się na procesie gamma z efektami losowymi, dzięki czemu pozwala na lepszą analizę degradacji. Model ten zastosowano do analizy wzrostu temperatury w metalowych wytłoczkach, na które oddziałuje wiele zmiennych objaśniających. Ponadto do oszacowania nieznanych parametrów wykorzystano metodę wnioskowania statystycznego opartą na podejściu bayesowskim. Umożliwiło to analizę niezawodności po uzyskaniu rozkładów czasu pierwszego przejścia.
Źródło:
Eksploatacja i Niezawodność; 2019, 21, 4; 654-661
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Atomic scale study of silver sulfide leaching with cyanide and thiourea
Autorzy:
Bernaola-Flores, Roxana
Silva-Quiñones, Dhamelyz
Balbuena, Perla B.
Rodríguez-Reyes, Juan Carlos F.
Tarazona-Vasquez, Francisco
Powiązania:
https://bibliotekanauki.pl/articles/109763.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
leaching
cyanidation
thioureation
DFT
cluster models
Ag2S
Opis:
Understanding of atomic scale interactions of molecular species with mineral surfaces is needed to bring about mineral processing innovation. In this regard, Density Functional Theory (DFT) methods are well suited. In this work, the outcome of leaching synthetic acanthite –a surrogate for a silver-containing sulfide ore- with both cyanide ion and thiourea are studied with DFT considering solvent effects. The results are correlated to the experimental percentage of silver extracted with each of the leaching agents under similar conditions of molar concentration, temperature and percentage of solids. Our calculations show both leaching reactions to be exergonic and of the same order of magnitude in Gibbs energy of reaction than values determined from thermodynamic tables. Also, less favorable Gibbs reaction energies are obtained for cyanidation in absence of oxygen and thioureation in absence of Fe(II) highlighting the impact of oxidants on the exergonicity of the respective global leaching reactions. Finally, analyzing the percentage of silver extracted from acanthite and the absolute value of Gibbs energies of the respective reaction, we conclude that the more exergonic a leaching reaction, the higher percentage of silver is extracted from acanthite, provided that there is no kinetic control of each of the leaching reactions.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 4; 969-980
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis of SrTiO3 by the Calcination of SrCO3 and TiO2 Mixtures Intensively Ground by Means of High Energy Milling
Autorzy:
Rocha-Rangel, Enrique
Pech-Rodríguez, Wilian J.
López-Hernández, Juan
Calles-Arriaga, Carlos A.
Armendáriz-Mireles, Eddie N.
Castillo-Robles, José A.
Rodríguez-García, José A.
Powiązania:
https://bibliotekanauki.pl/articles/356247.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
SrTiO3
mechanochemistry
insulating ceramics
perovskite
Opis:
A SrTiO3 electroceramic with perovskite structure was produced by the calcination of a mixture of SrCO3 and TiO2 intensively grounded by high energy milling. For this purpose, raw materials were mixed in stoichiometric amounts in a planetary type mill; the obtained powder mixture was calcined for 2 h at temperatures between 800 and 1300°C. Samples resulting from the calcination were characterized by XRD, FTIR, SEM analysis and electrical measurements. From XRD, it was determined that the SrTiO3 formed presents the cubic structure of perovskite. The complete reaction for SrTiO3 compound formation occurs at 1200°C. Micrograph observations indicate the presence of a homogeneous microstructure with tiny grain size. The measured values of electrical resistivity were within the typical range of insulating materials.
Źródło:
Archives of Metallurgy and Materials; 2020, 65, 2; 621-626
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Purification and characterization of GlcNAc-6-P 2-epimerase from Escherichia coli K92
Autorzy:
Ferrero, Miguel
Martínez-Blanco, Honorina
Lopez-Velasco, Federico
Ezquerro-Sáenz, Carlos
Navasa, Nicolas
Lozano, Sofia
Rodríguez-Aparicio, Leandro
Powiązania:
https://bibliotekanauki.pl/articles/1041092.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
sialic acid
capsular polysialic acid
N-acetylglucosamine
2-epimerase
Opis:
N-Acetylmannosamine (ManNAc) is the first committed intermediate in sialic acid metabolism. Thus, the mechanisms that control intracellular ManNAc levels are important regulators of sialic acid production. In prokaryotic organisms, UDP-N-acetylglucosamine (GlcNAc) 2-epimerase and GlcNAc-6-P 2-epimerase are two enzymes capable of generating ManNAc from UDP-GlcNAc and GlcNAc-6-P, respectively. We have purified for the first time native GlcNAc-6-P 2-epimerase from bacterial source to apparent homogeneity (1 200 fold) using Butyl-agarose, DEAE-FPLC and Mannose-6-P-agarose chromatography. By SDS/PAGE the pure enzyme showed a molecular mass of 38.4 ± 0.2 kDa. The maximum activity was achieved at pH 7.8 and 37°C. Under these conditions, the Km calculated for GlcNAc-6-P was 1.5 mM. The 2-epimerase activity was activated by Na+ and inhibited by mannose-6-P but not mannose-1-P. Genetic analysis revealed high homology with bacterial isomerases. GlcNAc-6-P 2-epimerase from E. coli K92 is a ManNAc-inducible protein and is detected from the early logarithmic phase of growth. Our results indicate that, unlike UDP-GlcNAc 2-epimerase, which promotes the biosynthesis of sialic acid, GlcNAc-6-P 2-epimerase plays a catabolic role. When E. coli grows using ManNAc as a carbon source, this enzyme converts the intracellular ManNAc-6-P generated into GlcNAc-6-P, diverting the metabolic flux of ManNAc to GlcNAc.
Źródło:
Acta Biochimica Polonica; 2007, 54, 2; 387-399
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Engineering Graduate Studies for Public Security Professionals: the Bachelor Thesis at the End of the Studies
Autorzy:
Loya, Jose Antonio
Moreno, Carlos Edgar
Rodríguez, Marcos
Miguelez, Maria Henar
Moure, Fernando
del Moral, Anselmo
Verón, Emilio José
Powiązania:
https://bibliotekanauki.pl/articles/504164.pdf
Data publikacji:
2014
Wydawca:
Międzynarodowa Wyższa Szkoła Logistyki i Transportu
Tematy:
Bachelor Thesis
Security Engineering Degree Engineering Degree
Opis:
This work presents the latest results concerning the Bachelor Thesis developed at the end of the fourth course in the Security Engineering Degree. A combined approach has been selected applying technological issues to crime problems, and also attending to legal and social aspects involved.
Źródło:
Logistics and Transport; 2014, 24, 4; 49-52
1734-2015
Pojawia się w:
Logistics and Transport
Dostawca treści:
Biblioteka Nauki
Artykuł

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