157 research outputs found
Identification of nucleocytoplasmic transport signals in Rps15 and Ltv1, two proteins related to small ribosomal subunit export
[EN] Ribosomes are indispensable organelles for cell survival. Eukaryotic ribosomes are made up of two subunits (60S and 40S), which are independently exported from the nucleolus to the cytoplasm, where they are finally assembled to form the functional ribosome. Due to their large size, ribosomal subunits need nuclear transport receptors, or karyopherins (such as the export receptor XPO1), to move through the nuclear pore complex. Karyopherins recognize cargo proteins bearing nucleocytoplasmic transport signals (nuclear localization signals (NLSs) or nuclear export signals (NESs)). In addition to karyopherins, nucleocytoplasmic transport of the small ribosomal subunit (40S), requires other factors, such as the ribosomal protein Rps15 and the non-ribosomal protein Ltv1. Due to the role of these proteins in the export of small ribosomal subunit, we hypothesized that they could carry still uncharacterized nucleocytoplasmic transport signals. Here we describe the identification of three new functional nuclear transport signals: one NLS and one NES in Rps15, as well as one NLS in Ltv1. Our results provide new information on the specific amino acid sequences that contribute to the function of Ltv1 and Rps15 as adapters in the nuclear export of the small ribosomal subunit.[ES] Los ribosomas son orgánulos indispensables para la supervivencia de la célula. Los ribosomas eucariotas están compuestos por dos subunidades (60S y 40S), que se exportan desde el nucleolo hasta el citoplasma de forma independiente, donde son finalmente ensambladas para dar lugar al ribosoma funcional. Debido a su gran tamaño, las subunidades ribosómicas necesitan receptores de transporte nuclear, o carioferinas (como el receptor de exportación XPO1), para atravesar el complejo del poro nuclear. Las carioferinas reconocen proteínas “cargo” que portan señales de transporte nucleocitoplásmico (señales de localización nuclear (NLSs) o señales de exportación nuclear (NESs)). Además de las carioferinas, el transporte nucleocitoplásmico de la subunidad ribosómica pequeña (40S), requiere otros factores, como la proteína ribosómica Rps15 y la proteína no ribosómica Ltv1. Debido al importante papel que juegan en la exportación de la subunidad ribosómica pequeña, planteamos la hipótesis de que estas proteínas podrían poseer señales de transporte nucleocitoplásmico aún sin caracterizar. Aquí describimos la identificación de tres nuevas señales de transporte nuclear funcionales: una NLS y una NES en Rps15, así como una NLS en Ltv1. Nuestros resultados aportan nueva información sobre las secuencias de aminoácidos concretas que contribuyen al funcionamiento de Ltv1 y de Rps15 como adaptadores en la exportación nuclear de la subunidad ribosómica pequeña
Identification of nucleocytoplasmic transport signals in Rps15 and Ltv1, two proteins related to small ribosomal subunit export
[EN] Ribosomes are indispensable organelles for cell survival. Eukaryotic ribosomes are made up of two subunits (60S and 40S), which are independently exported from the nucleolus to the cytoplasm, where they are finally assembled to form the functional ribosome. Due to their large size, ribosomal subunits need nuclear transport receptors, or karyopherins (such as the export receptor XPO1), to move through the nuclear pore complex. Karyopherins recognize cargo proteins bearing nucleocytoplasmic transport signals (nuclear localization signals (NLSs) or nuclear export signals (NESs)). In addition to karyopherins, nucleocytoplasmic transport of the small ribosomal subunit (40S), requires other factors, such as the ribosomal protein Rps15 and the non-ribosomal protein Ltv1. Due to the role of these proteins in the export of small ribosomal subunit, we hypothesized that they could carry still uncharacterized nucleocytoplasmic transport signals. Here we describe the identification of three new functional nuclear transport signals: one NLS and one NES in Rps15, as well as one NLS in Ltv1. Our results provide new information on the specific amino acid sequences that contribute to the function of Ltv1 and Rps15 as adapters in the nuclear export of the small ribosomal subunit.[ES] Los ribosomas son orgánulos indispensables para la supervivencia de la célula. Los ribosomas eucariotas están compuestos por dos subunidades (60S y 40S), que se exportan desde el nucleolo hasta el citoplasma de forma independiente, donde son finalmente ensambladas para dar lugar al ribosoma funcional. Debido a su gran tamaño, las subunidades ribosómicas necesitan receptores de transporte nuclear, o carioferinas (como el receptor de exportación XPO1), para atravesar el complejo del poro nuclear. Las carioferinas reconocen proteínas “cargo” que portan señales de transporte nucleocitoplásmico (señales de localización nuclear (NLSs) o señales de exportación nuclear (NESs)). Además de las carioferinas, el transporte nucleocitoplásmico de la subunidad ribosómica pequeña (40S), requiere otros factores, como la proteína ribosómica Rps15 y la proteína no ribosómica Ltv1. Debido al importante papel que juegan en la exportación de la subunidad ribosómica pequeña, planteamos la hipótesis de que estas proteínas podrían poseer señales de transporte nucleocitoplásmico aún sin caracterizar. Aquí describimos la identificación de tres nuevas señales de transporte nuclear funcionales: una NLS y una NES en Rps15, así como una NLS en Ltv1. Nuestros resultados aportan nueva información sobre las secuencias de aminoácidos concretas que contribuyen al funcionamiento de Ltv1 y de Rps15 como adaptadores en la exportación nuclear de la subunidad ribosómica pequeña
Ru-Promoted Ni/γAl2O3 Fluidized Catalyst for Biomass Gasification
Fluidizable catalysts based on Ni/γAl2O3 with added Ru were used for the gasification of
a lignin surrogate (2-methoxy-4-methylphenol) in a fluidized CREC Riser Simulator reactor. This was
done in order to quantify lignin surrogate conversion and lignin surrogate products (H2, CO, CO2 and
CH4) as well as the coke deposited on the catalyst. The catalysts that were evaluated contained 5% wt. Ni
with various Ru loadings (0.25%, 0.5% and 1% wt). These catalysts were synthesized using an incipient
Ni and Ru co-impregnation. Catalysts were characterized using XRD, N2 adsorption-desorption (BET
Surface Area, BJH), Temperature Programmed Reduction (TPR), Temperature Programmed Desorption
(TPD) and H2 chemisorption. Catalytic steam gasification took place at 550, 600 and 650 ◦C using 0.5,
1.0 and 1.5, steam/biomass ratios. The results obtained showed that Ru addition helped to decrease
both nickel crystallite site sizes and catalyst acid site density. Moreover, it was observed that coke on
the catalyst was reduced by 60%. This was the case when compared to the runs with the Ni/γAl2O3
free of Ru
Catalytic Steam Gasification of Glucose for Hydrogen Production Using Stable Based Ni on a γ–Alumina Fluidizable Catalyst
Six different Ni-based fluidizable catalysts were synthesized using both incipient impregnation and co-
impregnation. Ni-based catalysts were also promoted with 2.0 wt% La or alternatively with 2 wt% Ce. The
preparation procedure included catalysts treated at high temperatures and under free of oxygen conditions.
Catalysts were characterized using BET, XRD, AA, PSD, TPR, TPD, H2-chemisorption. TPR and H2 chemisorp-tion showed good metal dispersion with 10 nm- 40 nm metal crystallites.
Glucose catalytic gasification runs were performed in a CREC Riser Simulator to evaluate the following cata-
lysts: (a) 5 %Ni/γ-Al2O3, (b) 5 %Ni-2 %La/γ-Al2O3 and (c) 5 %Ni-2 %Ce/γ-Al2O3. In all cases, the preparation
steps involved acid solutions with pHs of 1 and 4. In between consecutive runs, different approaches were
considered: (a) A catalyst was regenerated by air, (b) A catalyst was regenerated by air followed by hydrogen
pretreatment, (c) A catalyst was reused directly without any regeneration or hydrogen pretreatment. It was
observed that Ni-based catalysts, which were subjected after every run, to both, air regeneration and hydro-
gen pretreatment, displayed the best yields in close agreement with thermodynamic equilibrium. On the other
hand, Ni-based catalysts regenerated with air only, showed the worst hydrogen yields. In between these two-
hydrogen yield limits, where catalysts not contacted with air nor hydrogen, with these yields being moderately
below chemical equilibrium.
This shows that Ni-based fluidizable catalysts can perform on stream for extended periods, requiring limited
reactivation with air and H2. This makes of gasification using the catalysts of the present study, a viable process alternative that could be implemented at industrial scale
Virtual 3D environment as a support stragey to the listening learning in English as a foreing language in the students of english 1 at Uniminuto
This research gets importance at the moment of thinking about benefits that will be add not only to students but also to teachers, to the University and to the teaching English as a foreign language field. For this reason, in the next paragraphs it will be described the importance of studying this problem for students, teachers and the English teaching field.
It makes necessary to study this problem because students of English 1, are students of all programs at “Uniminuto” (Corporacion Univeristaria Minuto de Dios) (except for the students of the English teaching program)
Towards a new classification of galaxies: principal component analysis of CALIFA circular velocity curves
We present a galaxy classification system for 238 (E1-Sdm) CALIFA (Calar Alto
Legacy Integral Field Area) galaxies based on the shapes and amplitudes of
their circular velocity curves (CVCs). We infer the CVCs from the de-projected
surface brightness of the galaxies, after scaling by a constant mass-to-light
ratio based on stellar dynamics - solving axisymmetric Jeans equations via
fitting the second velocity moment of
the stellar kinematics. We use principal component analysis (PCA) applied to
the CVC shapes to find characteristic features and use a -means classifier
to separate circular curves into classes. This objective classification method
identifies four different classes, which we name slow-rising (SR), flat (FL),
round-peaked (RP) and sharp-peaked (SP) circular curves.
SR are typical for low-mass, late-type (Sb-Sdm), young, faint, metal-poor and
disc-dominated galaxies. SP are typical for high-mass, early-type (E1-E7), old,
bright, metal-rich and bulge-dominated galaxies. FL and RP appear presented by
galaxies with intermediate mass, age, luminosity, metallicity, bulge-to-disk
ratio and morphologies (E4-S0a, Sa-Sbc). The discrepancy mass factor,
, have the largest value for SR and SP classes ( 74
per cent and 71 per cent, respectively) in contrast to the FL and RP
classes (with 59 per cent and 61 per cent, respectively).
Circular curve classification presents an alternative to typical morphological
classification and appears more tightly linked to galaxy evolution.Comment: Accepted for publication in MNRAS (Minor changes), 123 pages, 19
figures, 87 Tables (containing the basic properties of the 238 E1-Sdm
galaxies; the five main Principal Component Eigenvectors; the five main
Principal Components - PC_i; the Multi-Gaussian Expansion models - MGEs; the
circular velocity curve models and their uncertainties
Epidemiología y parasitismo gastrointestinal en equinos del departamento Maracó, provincia de La Pampa, República Argentina
An epidemiologic survey of the gastrointestinal parasites that affect equines was carried out in 4 farms in Maracó Department, La Pampa Province, from March 15, 2005 to February 28, 2007.Ten equines chosen randomly from each farm were evaluated. The sample results of faecal matter taken each month showed the h.p.g. porcentages higher in the months of January, February, March, November and December (P 0,001). The species found were Cyatostomun spp. 76%,Triodonthophorus Triodonthophorus spp. 17,5%, Strongylus spp. 4,5 % y Trichostrongylus spp. 2%. Samples of the pastures were taken every fifteen days in the pasture grounds where the equines under study were grazing.The greatest amount of larvae were observed in the months of March,April, May, October and November (P 0,01) and the most important genre found were Cyatostomun spp. 71%, Triodontophorus spp. 19,5%, Strongylus spp. 7,5% yTrichostrongylus spp. 2%.These results suggested that the antiparasitic treatments should be undergone in autumn, spring and summerEn 4 establecimientos rurales del Departamento Maracó, Provincia de La Pampa, se realizó un estudio epidemiológico de los parásitos gastrointestinales que afectan a los equinos durante el período comprendido desde el 15/3/05 hasta el 28/2/07. Se evaluaron 10 equinos elegidos al azar de cada establecimiento. Los resultados de las muestras de materia fecal tomadas mensualmente mostraron los porcentajes de h.p.g. mayores en los meses de enero, febrero, marzo, noviembre y diciembre (P <0,01). Las especies encontradas fueron Cyatostomum spp. 76%, Triodontophorus spp. 17,5%, Strongylus spp. 4,5% y Trichostrongylus spp. 2%. Las muestras de pasturas se tomaron cada 15 días en los potreros donde pastaban los equinos en estudio. El mayor porcentaje de larvas se observó en los meses de marzo, abril, mayo, octubre y noviembre (P <0,01) y los principales géneros encontrados fueron Cyatostomum spp. 71 %, Triodontophorus spp. 19,5 %, Strongylus spp. 7,5 % y Trichostrongylus spp. 2%. Estos resultados sugieren que los tratamientos antiparasitarios deberían realizarse en otoño, primavera y verano
EQUIDAD DE GÉNERO UNA MIRADA DESDE TERAPIA OCUPACIONAL
Objetivo: relacionar la competencia ocupacional y la equidad de género de la población femenina del municipio de Villa del Rosario Metodología: Para esta investigación se realizó la aplicación del perfil ocupacional inicial del MOHOST evaluando 6 criterios; motivación, patrón de ocupación, habilidades de comunicación e interacción, habilidades de procesamiento, habilidades motoras y ambiente, lo que permitió identificar la situación de la Mujer Rosariense y así obtener un análisis del equilibrio ocupacional a través de grupos institucionales que permitieron incluir a la población femenina en actividades de su interés mediante talleres productivos, psicoeducativas y vocacionales o de trabajo. Esta investigación se aplicó a 100 mujeres del municipio de Villa del Rosario a través una metodología de un enfoque mixto, bajo un diseño exploratorio, descriptivo explicativo y correlacional. Resultados: se evidenció que las mujeres estudiadas se perciben excluidas en los ámbitos social, político y laboral, asimismo, hay escaza capacidad de elección de sus actividades y ocupaciones. Conclusiones: las mujeres perciben que existe inequidad de género, por tal motivo se generaron intervenciones para concientizar y motivar a esta población en cuanto su rol productivo logrando así su inclusión en actividades que les brindan gratificación personal y económica
Actividades motivacionales y de metaconocimiento dirigidas a mejorar el pensamiento crítico
Memoria ID12-0152. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2012-2013
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