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OALib Journal期刊

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Investigación en Ingeniería de Software en la carrera de Ingeniería en Ciencias Informáticas. Software Engineering Research at the University of Informatics Sciences
Julio Cesar Diaz Vera
Avanzada Científica , 2012,
Abstract: Los procesos de investigación en Ingeniería de Software en Cuba carecen de suficiente claridad, principalmente por el nivel de madurez alcanzado en esta disciplina. Este elemento dificulta la capacidad de los investigadores noveles para dise ar sus propias estrategias de investigación o reconocer investigaciones de excelencia. En este trabajo se caracterizan las estrategias de investigación en la Universidad de Ciencias Informáticas, se comparan con las estrategias utilizadas internacionalmente y se determina el nivel de madurez de la investigación relacionada con esta área del conocimiento en la universidad. Los resultados alcanzados constituyen una contribución para el dise o de las investigaciones en Ingeniería de Software y la presentación de sus aportes con mayor claridad e impacto.
Peroxidase activity, soluble proteins and chlorophyll content in spruce (Picea abies L. Karst.) needles affected by cement dust
Cesar, Vera,Lepedu？, Hrvoje
- , 2001,
Abstract: Sa？etak The correlation between the peroxidase activity, chlorophyll and soluble protein content as well as the changes in vascular bundle structure in Norway spruce (Picea abies L. Karst.) needles affected by cement dust were studied. In spite of the absence of any yellowing symptoms, a significantly lower chlorophyll content was measured in spruce needles affected by cement dust. Observed sieve cells distortions in needle samples indicated that spruce trees grown near the cement factory were Mg deficient. Total guaiacol peroxidase activity in non-af- fected was significantly higher than in dust-affected needles, while soluble protein content was not significantly different
CARACTERIZACIóN SUPERFICIAL, ELECTROQUíMICA Y DE COMPOSICIóN DE ALEACIONES ZINC NíQUEL ELECTRODEPOSITADAS
PIRATOBA,ULISES; VERA,ENRIQUE; ORTIZ,CESAR;
DYNA , 2008,
Abstract: the high request for zinc or zinc alloys electro coating steel sheets is attended by continuous electro coating process; this required high current densities obtained in acidic electrolytes. in this work, the composition, surface morphology and electrochemical characterization of gamma phase zinc nickel alloys on cold rolled steel sheets, obtained with high current densities is present. these were determined by energy dispersive x-ray analysis edx, scanning electron microscopy sem and atomic force microscopy afm, and electrochemical impedance ei and tafel polarization. it was find passive coatings of fine grain that exhibit anodic behavior against the steel substrate.
CARACTERIZACIóN SUPERFICIAL, ELECTROQUíMICA Y DE COMPOSICIóN DE ALEACIONES ZINC NíQUEL ELECTRODEPOSITADAS
ULISES PIRATOBA,ENRIQUE VERA,CESAR ORTIZ
DYNA , 2008,
Abstract: La gran demanda de láminas de acero recubiertas con Zinc o con aleaciones de Zinc, es atendida conprocesos de electro deposición en continuo; estos requieren de altas densidades de corriente, obtenidas en electrolitos ácidos. En este trabajo se presenta la composición, morfología superficial y la caracterización electroquímica de aleaciones Zinc Níquel fase gamma sobre láminas de acero, depositadas con altas densidades de corriente. Estas fueron determinadas mediante Análisis de Energía Dispersa de Rayos EDX, Microscopias Electrónica de Barrido SEM y de Fuerza Atómica AFM, e Impedancia Electroquímica EI y polarización Táfel. Se encontraron recubrimientos de grano fino que se pasivan y exhiben un comportamiento anódico frente al sustrato de acero.
The effect of 2,4-D on the photosynthetic apparatus in cotyledons of spruce (Picea abies L. Karst.) seedlings grown in the dark
Cesar, Vera,Lepedu？, Hrvoje,Ljube？i？, Nikola
- , 2001,
Abstract: Sa？etak Growth regulating substance, 2,4-dichlorophenoxyacetic acid (2,4-D) is widely used in plant cell cultures and also in agriculture as a herbicide. The effect of 2,4-D on photosynthetic pigment content and chloroplast ultrastructure in spruce seedlings grown in the dark was studied. Seedlings were grown for 16 days in the dark at room temperature in Petri dishes moistened either with tap water (control) or 4.5, 45 and 450 μM 2,4-D. The lowest concentration (4.5 μM) of 2,4-D induced both chlorophyll and carotenoid biosynthesis as compared to the control treatment. There were no statistically significant differences in any of the measured parameters between the control and the 45 μM 2,4-D treatment. A herbicidal concentration of 2,4-D (450 μM) induced a decline in chlorophyll content, while carotenoids were not significantly influenced. In contrast to the low concentration treatments, a herbicidal concentration of 2,4-D caused extensive changes in chloroplast shape and ultrastructure
Gvajakol-peroksidaze i fotosintetski pigmenti u razli？ito starim iglicama smreke
Cesar, Vera,Ga？a, Vlatka,Lepedu？, Hrvoje
- , 2005,
Abstract: Sa？etak Prou？avane su promjene u aktivnosti gvajakol-peroksidaza, u elektroforetskome sastavu, u sadr？aju fotosintetskih pigmenata i u？inkovitosti fotosustava II u iglicama smreke (Picea abies L. Karst.) razli？ite starosti. ？etiri generacije iglica (ovogodi？nje, jedno-, dvo- i trogodi？nje) prikupljene su s deset stabala smreke. Sli？ne Fv/Fm vrijednosti u svim ispitivanim iglicama pokazuju da su zdrave s potpuno funkcionalnim fotosustavom II. Zna？ajno pove？anje sadr？aja fotosintetskih pigmenata se dogodilo tijekom prve godine razvoja. Ukupna aktivnost gvajakol-peroksidaza pove？avala se kontinuirano tijekom starenja iglica. Statisti？ka zna？ajnost utvr？ena je izme？u ovogodi？njih i starijih iglica te izme？u jednogodi？njih i trogodi？njih iglica. Pojava novih izoformi peroksidaza uo？ena je u jednogodi？njim iglicama u odnosu na ovogodi？nje iglice. Izme？u jednogodi？ njih, dvogodi？njih i trogodi？njih iglica nisu uo？ene promjene u sastavu izoformi peroksidaza. Dobiveni rezultati pokazuju da iglice smreke podlije？u najintenzivnijim biokemijskim i molekularnim promjenama tijekom prve godine razvoja
First isolation and identification of H1N1 swine influenza viruses in Colombian pig farms  [PDF]
Gloria Consuelo Ramirez-Nieto, Cesar Augusto Diaz Rojas, Victor Julio Vera Alfonso, Jairo Jaime Correa, Jose Dario Mogollon Galvis
Health (Health) , 2012, DOI: 10.4236/health.2012.430150
Abstract: The pig industry in Colombia has grown 30% in the last decade achieving high levels of technology and efficiency; in spite of that, respiratory diseases remain a constraint. Since 1970, serological evidence and histological findings suggested the role of swine influenza virus (SIV) as part of the porcine respiratory disease complex; nevertheless, elusive and molecular typing isolates are missing. This study was aimed at isolating SIV from intensive pig farms and to achieve molecular characterization to determine strains circulating in the field. In order to accomplish this goal, 242 samples were taken from nasal swabs, 25 from bronchial washes and 8 from lung tissue. Samples were collected during a period of three years, between 2008 and 2010 and were originated from 78 farms of the three main pig production regions of the country. The samples were transported in BHI broth with 2% antibiotic and antimycotic solution and stored at –70?C until processed. The swabs were inoculated in 9 - 11 days old embryo chicken eggs and in MDCK (Madin Darby Canine Kidney) cell cultures with the addition of trypsin. The isolates were identified by the HA (hemoagglutination) test and by RT-PCR targeting the HA (hemagglutinin), NA (Neuraminidase) and M (Matrix) genes. Full length sequence of the HA and NA glycoproteins from four selected virus isolates was conducted (Macrogen?. USA). As a result, fifteen SIV isolates from nine farms distributed in the three regions were obtained. Twelve of the isolates are related to the swine origin H1N1 virus that caused the 2009 influenza pandemic. The remaining three viruses were related to classical swine influenza viruses.
THE ROLE OF LIGHT REGIME AND SUBSTRATE IN PHOTOSYNTHETIC PIGMENTS, FREE PROLINE CONTENT AND FLOWER QUALITY OF GERBERA JAMESONII L.
Nada Para？ikovi？,Jadranka Mustapi？-Karli？,Tihana Tekli？,Vera Cesar
Poljoprivreda (Osijek) , 2008,
Abstract: The research of light and substrate role in leaf photosynthetic pigments, free proline content and flower quality indices in two gerbera cultivars (Vino and Ruby Red) showed that flower stems were longer in additional lighting treatment, coco’s peat amended with rice chaff and cultivar Ruby Red. Chlorophyll b concentration was in negative relation to leaf proline content and correlated to longer flower stems. In general, the higher leaf total chlorophyll concentration was related to longer stems, and such stems have had larger flower heads. Flower head diameter did not differ significantly between cultivars; it depended on light regime, substrate and their interaction.
PHOTOSYNTHETIC EFFICIENCY IN JUVENILE STAGE AND WINTER BARLEY BREEDING FOR IMPROVED GRAIN YIELD AND STABILITY
Josip Kova？evi？,Maja Kova？evi？,Vera Cesar,Alojzije Lali？
Poljoprivreda (Osijek) , 2011,
Abstract: Photosynthetic efficiency parameters (Fv/Fm, ET0/ABS and PIABS) were investigated at the end of tillering stage of winter barley grown in stress environment (21.3% vol. water content of soil) and control (water content 30.4% vol.) in relation to grain yield per vegetative pot. The trial was conducted in vegetative pots according to the RBD method of two-factorial experiment with 10 winter barley cultivars (7 tworowed and 3 six-rowed) and 2 treatments in 3 repetitions. The stressed variant was exposed to water reduction three times (end of tillering stage, flag leaf to beginning of heading stage, grain filling stage). From sowing to maturity, the air temperature varied from -3.9°C to 32.9°C and water content from 16.4 % to 39.0 % of soil volume in vegetative pot. Significant differences were found for grain yield among the cultivars. The short-term drought stress caused significant reductions in grain yield per pot. The photosynthetic efficiency parameters were significant between cultivars, but significant effects for treatments and interaction were only detected for the Fv/Fm parameter. Photosynthetic efficiency parameters did not have significant correlation coefficients with grain yield and its stability in both treatments. Stability indexes of the parameters PIABS and Fv/Fm had positive but not significant correlations with grain yield in stressed variant (0.465 and 0.452) and stability index of grain yield (0.337 and 0.481).
Contribui es do estágio extracurricular para as competências profissionais: percep es de enfermeiros de um hospital público
Kely Cesar Martins de Paiva,Vera Lúcia Vieira Martins
Revista Eletr？nica de Enfermagem , 2011,
Abstract: Este estudo teve como objetivo descrever e analisar como os enfermeiros de um hospital público de Belo Horizonte (MG) percebem as contribui es ideais (desejada) e reais (efetiva), do estágio extracurricular para o processo de forma o e desenvolvimento de competências profissionais dos acadêmicos de Enfermagem, dada sua importancia na forma o acadêmica e profissional do estudante durante tal processo pedagógico. Na pesquisa de campo, descritiva e com abordagem quantitativa, os dados foram coletados por meio de um questionário aplicado a 65 enfermeiros que acompanham os acadêmicos durante o estágio extracurricular. Os resultados mostraram que, tanto do ponto de vista do ideal como do real, tal modalidade de estágio tem contribuído para a forma o dos acadêmicos. No entanto, alguns pontos de defasagem foram identificados, os quais carecem de aten o por parte de todos os atores envolvidos: Estado, institui es de ensino, o hospital, os acadêmicos e os enfermeiros que os acompanham.
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