Variação temporal de propriedades físicas do solo e crescimento radicular de feijoeiro em quatro sistemas de manejo

Os objetivos deste trabalho foram determinar a variação temporal da porosidade, da densidade e da resistência à penetração do solo, em quatro sistemas de manejo, e estudar seus efeitos sobre o crescimento radicular do feijoeiro (Phaseolus vulgaris). O experimento foi conduzido em Argissolo, em delineamento experimental de blocos ao acaso, com três repetições. Os tratamentos foram: plantio direto há 10 anos, preparo convencional, plantio em solo escarificado recentemente (Esc. recente) e plantio direto sobre área escarificada há 1 ano (Esc. 1 ano). A escarificação reduziu a densidade média do solo e aumentou a porosidade total durante o ciclo do feijoeiro. A maior densidade ocorreu na camada de 0,10-0,15 m dos sistemas plantio direto e Esc. 1 ano. A resistência à penetração foi a propriedade que melhor caracterizou e diferenciou os sistemas de manejo, as camadas com impedimento e o efeito do tempo de amostragem, porém não afetou o crescimento radicular do feijoeiro. Os efeitos da escarificação sobre a densidade e a resistência à penetração desapareceram um ano após a escarificação, o que indica a reconsolidação do solo.

Estimating soybean crop areas using spectral-temporal surfaces derived from MODIS images in Mato Grosso, Brazil

The objective of this work was to evaluate the application of the spectral-temporal response surface (STRS) classification method on Moderate Resolution Imaging Spectroradiometer (MODIS, 250 m) sensor images in order to estimate soybean areas in Mato Grosso state, Brazil. The classification was carried out using the maximum likelihood algorithm (MLA) adapted to the STRS method. Thirty segments of 30x30 km were chosen along the main agricultural regions of Mato Grosso state, using data from the summer season of 2005/2006 (from October to March), and were mapped based on fieldwork data, TM/Landsat-5 and CCD/CBERS-2 images. Five thematic classes were considered: Soybean, Forest, Cerrado, Pasture and Bare Soil. The classification by the STRS method was done over an area intersected with a subset of 30x30-km segments. In regions with soybean predominance, STRS classification overestimated in 21.31% of the reference values. In regions where soybean fields were less prevalent, the classifier overestimated 132.37% in the acreage of the reference. The overall classification accuracy was 80%. MODIS sensor images and the STRS algorithm showed to be promising for the classification of soybean areas in regions with the predominance of large farms. However, the results for fragmented areas and smaller farms were less efficient, overestimating soybean areas.

Una proposta d’ensenyament aprenentatge basada en l’aprenentatge cooperatiu i el wiki com a eina afavoridora del treball compartit en els estudis de magisteri.

Presentem una experiència que s'ha desenvolupant en la diplomatura de Magisteri de la FPCEE Blanquerna de la URL durant els cursos 2008/09 i 2009/10 en el marc del procés d'implantació dels crèdits ECTS en els futurs graus d'Educació Primària. Aquesta forma part dels projectes seleccionats i finançats per al disseny, la planificació i l’avaluació de mòduls docents i seminaris dels nous plans d'estudis de grau. L'objectiu principal del projecte ha estat organitzar i experimentar l’ensenyament i l’aprenentatge des de dues assignatures de tercer curs de l’especialitat d’Educació Primària amb un enfocament metodològic interdisciplinari basat en l’aprenentatge en equips cooperatius amb el suport TIC. Cada curs han participat uns 60 estudiants distribuïts en 12 grups de treball cooperatiu. Per a l’ elaboració i seguiment del treball, s'ha escollit utilitzar els Wikis com a eina que facilita el treball cooperatiu, i així tant el professorat implicat en el projecte com cada grup ha creat el seu wiki a wikispaces: http://www.wikispaces.com/site/for/teachers i GoogleDocs per a la implementació i recollida d'informació de les tutories de seguiment i avaluació del treball fet pels estudiants. Finalment, hem analitzat i valorat el grau de satisfacció dels estudiants i professorat que ha participat tant en el disseny com en el desplegament de l'experiència i la consecució dels objectius previstos.

Spatio-temporal sequence of cross-regulatory events in root meristem growth.

A central question in developmental biology is how multicellular organisms coordinate cell division and differentiation to determine organ size. In Arabidopsis roots, this balance is controlled by cytokinin-induced expression of SHORT HYPOCOTYL 2 (SHY2) in the so-called transition zone of the meristem, where SHY2 negatively regulates auxin response factors (ARFs) by protein-protein interaction. The resulting down-regulation of PIN-FORMED (PIN) auxin efflux carriers is considered the key event in promoting differentiation of meristematic cells. Here we show that this regulation involves additional, intermediary factors and is spatio-temporally constrained. We found that the described cytokinin-auxin crosstalk antagonizes BREVIS RADIX (BRX) activity in the developing protophloem. BRX is an auxin-responsive target of the prototypical ARF MONOPTEROS (MP), a key promoter of vascular development, and transiently enhances PIN3 expression to promote meristem growth in young roots. At later stages, cytokinin induction of SHY2 in the vascular transition zone restricts BRX expression to down-regulate PIN3 and thus limit meristem growth. Interestingly, proper SHY2 expression requires BRX, which could reflect feedback on the auxin responsiveness of SHY2 because BRX protein can directly interact with MP, likely acting as a cofactor. Thus, cross-regulatory antagonism between BRX and SHY2 could determine ARF activity in the protophloem. Our data suggest a model in which the regulatory interactions favor BRX expression in the early proximal meristem and SHY2 prevails because of supplementary cytokinin induction in the later distal meristem. The complex equilibrium of this regulatory module might represent a universal switch in the transition toward differentiation in various developmental contexts.

Temporal evolution of MR perfusion in neonatal hypoxic-ischemic encephalopathy

PURPOSE: To illustrate the evolution of brain perfusion-weighted magnetic resonance imaging (PWI-MRI) in severe neonatal hypoxic-ischemic (HI) encephalopathy, and its possible relation to further neurodevelopmental outcome. MATERIALS AND METHODS: Two term neonates with HI encephalopathy underwent an early and a late MRI, including PWI. They were followed until eight months of age. A total of three "normal controls" were also included. Perfusion maps were obtained, and relative cerebral blood flow (rCBF) and cerebral blood volume (rCBV) values were measured. RESULTS: Compared to normal neonates, a hyperperfusion (increased rCBF and rCBV) was present on early scans in the whole brain. On late scans, hyperperfusion persisted in cortical gray matter (normalization of rCBF and rCBV ratios in white matter and basal ganglia, but not in cortical gray matter). Diffusion-weighted imaging (DWI) was normalized, and extensive lesions became visible on T2-weighted images. Both patients displayed very abnormal outcome: Patient 2 with the more abnormal early and late hyperperfusion being the worst. CONCLUSION: PWI in HI encephalopathy did not have the same temporal evolution as DWI, and remained abnormal for more than one week after injury. This could be a marker of an ongoing mechanism underlying severe neonatal HI encephalopathy. Evolution of PWI might help to predict further neurodevelopmental outcome.

Projecte Gutenberg : l'aplicació del mètode de treball per projectes per a l'edició d'un llibre

L’objectiu prioritari d’aquesta intervenció, presentada en el marc dels MQD (Mòduls de qualitat docent) del curs 2010-2011, titulada Projecte Gutenberg, ha estat la pràctica de realitzar uns treballs cooperatius amb un grup classe per tal d’assolir la competència bàsica de saber treballar en equip i de ser conscient de la responsabilitat que aquest treball requereix per part de cada alumne. La finalitat, però, d’aquest projecte ha estat també la publicació d’un opuscle (llibret amb ISBN) amb un total de deu articles a partir de cinc temàtiques diferents triades pels mateixos alumnes. Cada un d’aquests temes s’ha tractat des de dues perspectives diferents: una més global, des d’una visió social, i l’altra més concreta, des d’una visió educativa. Aquest projecte proposava tanmateix una activitat transversal programada duta a terme en el marc de la Trobada Internacional per la Pau celebrada a Barcelona i organitzada per la Comunitat de Sant Egidi, dels dies 3 al 5 d’octubre del 2010. El grup classe que ha participat d’aquest esdeveniment ha estat el de segon curs de Magisteri del Grau de Primària (EP, tarda). El projecte s’ha realitzat des del mòdul d’Humanitats Cristianisme i Cultura i des dels seminaris corresponents al mòdul 2, amb la col·laboració dels seus tutors/es durant el primer semestre del curs 2010-2011.

Les pràctiques d'FP com a eina de formacio i d'insercio en el mercat de treball

Quan analitzem I'evolució del nostre país en el camp educatiu, particularment en el camp de la formació, comprovarem que ha seguit un camí que, almenys en certa mesura, ha anat relacionat amb I'evolució económica i social, sense que aixó hagi d'implicar cap dependencia directa ni una total coordinació: de fet, cada subsistema social té la seva própia dinamica i les seves inercies...

Estudi sobre la influència de l'equilibri treball-família en la satisfacció i l’estrès a una organització catalana

A partir dels estudis previs sobre l’equilibri entre la vida familiar i laboral, es desenvolupa el present estudi sobre les relacions de l’equilibri treball-família en la satisfacció i l’estrès en una organització pública catalana. S’utilitza una mostra diversa de 123 treballadors, la qual inclou treballadors dediversos departaments amb diferenciació de treballs i tasques. L’estudi utilitza la tècnica multivariable dels models d’equacions estructurals que realitza estimacions de relacions causals a partir de dades estadístiques, les quals expressen el grau en què les dades s’ajusten a un model proposat, confirmant la seva validesa.Els resultats dels models d’equacions estructurals van demostrar que existeix una relació positiva entre l’equilibri treball-família amb la satisfacció laboral i la satisfacció familiar, en canvi aquesta relació és negativa quan es tracta de l’estrès. A més a més, els models d’equacions confirmen que existeix una correlació negativa entre la satisfacció laboral i l’estrès. Aquest estudi també confirma que l’equilibri treball-vida és un bon predictor sobre la satisfacció laboral.

Molecular phylogenetics and temporal diversification in the genus Aeromonas based on the sequences of five housekeeping genes

Several approaches have been developed to estimate both the relative and absolute rates of speciation and extinction within clades based on molecular phylogenetic reconstructions of evolutionary relationships, according to an underlying model of diversification. However, the macroevolutionary models established for eukaryotes have scarcely been used with prokaryotes. We have investigated the rate and pattern of cladogenesis in the genus Aeromonas (γ-Proteobacteria, Proteobacteria, Bacteria) using the sequences of five housekeeping genes and an uncorrelated relaxed-clock approach. To our knowledge, until now this analysis has never been applied to all the species described in a bacterial genus and thus opens up the possibility of establishing models of speciation from sequence data commonly used in phylogenetic studies of prokaryotes. Our results suggest that the genus Aeromonas began to diverge between 248 and 266 million years ago, exhibiting a constant divergence rate through the Phanerozoic, which could be described as a pure birth process.

Different methods to assess yield temporal stability in rubber

The objective of this work was to assess, during six years, the temporal stability of natural rubber yield of 25 superior Hevea brasiliensis genotypes, using the Wricke, Eberhart & Russell, Lin & Binns, additive main effect and multiplicative interaction (AMMI) analysis, and harmonic mean of the relative performance of the genetic values (HMRPGV) methods. The IAC 40 and IAC 300 genotypes were identified as stable and high yielding by the Eberhart & Russell, Lin & Binns, HMRPGV, and AMMI Biplot methods. The ranking of the other more stable genotypes identified by these analyses was altered. The observed results in the AMMI Biplot agreed with those observed in the Wricke method for identifying stable, but lower yielding genotypes. The simultaneous use of different methods allows a more accurate indication of stable genotypes. Stability analyses based on different principles show agreement in indicating stable genotypes.

Sensitivity of Spring Phenology to Warming Across Temporal and Spatial Climate Gradients in Two Independent Databases

Disparate ecological datasets are often organized into databases post hoc and then analyzed and interpreted in ways that may diverge from the purposes of the original data collections. Few studies, however, have attempted to quantify how biases inherent in these data (for example, species richness, replication, climate) affect their suitability for addressing broad scientific questions, especially in under-represented systems (for example, deserts, tropical forests) and wild communities. Here, we quantitatively compare the sensitivity of species first flowering and leafing dates to spring warmth in two phenological databases from the Northern Hemisphere. One-PEP725-has high replication within and across sites, but has low species diversity and spans a limited climate gradient. The other-NECTAR-includes many more species and a wider range of climates, but has fewer sites and low replication of species across sites. PEP725, despite low species diversity and relatively low seasonality, accurately captures the magnitude and seasonality of warming responses at climatically similar NECTAR sites, with most species showing earlier phenological events in response to warming. In NECTAR, the prevalence of temperature responders significantly declines with increasing mean annual temperature, a pattern that cannot be detected across the limited climate gradient spanned by the PEP725 flowering and leafing data. Our results showcase broad areas of agreement between the two databases, despite significant differences in species richness and geographic coverage, while also noting areas where including data across broader climate gradients may provide added value. Such comparisons help to identify gaps in our observations and knowledge base that can be addressed by ongoing monitoring and research efforts. Resolving these issues will be critical for improving predictions in understudied and under-sampled systems outside of the temperature seasonal mid-latitudes.

Temporal trends in chemical parameters of upland forest soils in southern Finland

Abstract

Coneixements sobre salut sexual i reproductiva en estudiants de Farmàcia (Treball Final de Grau)

Se presenta un TFG (Trabajo de Final de Grado) que se realizó durante el curso académico 2011-12 en el Grado de Farmacia de la UB. Su objetivo fue describir los conocimientos y opiniones de los estudiantes del Grado de Farmacia-UB, respecto a la prevención de enfermedades de transmisión sexual y embarazos no deseados.