Phylogenetic analysis of plastid and nuclear DNA sequences reveals a rapid late Miocene radiation of the temperate bamboo tribe Arundinarieae (Poaceae, Bambusoideae)

Background: Arundinarieae are a large tribe of temperate woody bamboos for which phylogenetics are poorly understood because of limited taxon sampling and lack of informative characters. Aims: This study assessed phylogenetic relationships, origins and classification of Arundinarieae. Methods: DNA sequences (plastid trnL-F; nuclear ITS) were used for parsimony and Bayesian inference including 41 woody bamboo taxa. Divergence dates were estimated using a relaxed Bayesian clock. Results: Arundinarieae were monophyletic but their molecular divergence was low compared to the tropical Bambuseae. Ancestors of the Arundinarieae lineage were estimated to have diverged from the other bamboos 23 (15-30) million years ago (Mya). However, the Arundinarieae radiation occurred 10 (6-16) Mya compared to 18 (11-25) Mya for the tropical Bambuseae. Some groups could be defined within Arundinarieae, but they do not correspond to recognised subtribes such as Arundinariinae or Shibataeinae. Conclusions: Arundinarieae are a relatively ancient bambusoid lineage that underwent a rapid radiation in the late Miocene. The radiation coincides with the continental collision of the Indo-Australian and Eurasian Plates. Arundinarieae are distributed primarily in East Asia and the Himalayas to northern Southeast Asia. It is unknown whether they were present in Asia long before their radiation, but we believe recent dispersal is a more likely scenario. Keywords: Arundinarieae; Bambuseae; internal transcribed spacer (ITS); molecular clock; phylogenetics; radiation; temperate bamboos; Thamnocalaminae; trnL-F

Childhood cancer and nuclear power plants in Switzerland: a census-based cohort study.

BACKGROUND: Previous studies on childhood cancer and nuclear power plants (NPPs) produced conflicting results. We used a cohort approach to examine whether residence near NPPs was associated with leukaemia or any childhood cancer in Switzerland. METHODS: We computed person-years at risk for children aged 0-15 years born in Switzerland from 1985 to 2009, based on the Swiss censuses 1990 and 2000 and identified cancer cases from the Swiss Childhood Cancer Registry. We geo-coded place of residence at birth and calculated incidence rate ratios (IRRs) with 95% confidence intervals (CIs) comparing the risk of cancer in children born <5 km, 5-10 km and 10-15 km from the nearest NPP with children born >15 km away, using Poisson regression models. RESULTS: We included 2925 children diagnosed with cancer during 21 117 524 person-years of follow-up; 953 (32.6%) had leukaemia. Eight and 12 children diagnosed with leukaemia at ages 0-4 and 0-15 years, and 18 and 31 children diagnosed with any cancer were born <5 km from a NPP. Compared with children born >15 km away, the IRRs (95% CI) for leukaemia in 0-4 and 0-15 year olds were 1.20 (0.60-2.41) and 1.05 (0.60-1.86), respectively. For any cancer, corresponding IRRs were 0.97 (0.61-1.54) and 0.89 (0.63-1.27). There was no evidence of a dose-response relationship with distance (P > 0.30). Results were similar for residence at diagnosis and at birth, and when adjusted for potential confounders. Results from sensitivity analyses were consistent with main results. CONCLUSIONS: This nationwide cohort study found little evidence of an association between residence near NPPs and the risk of leukaemia or any childhood cancer.

Implementation of population balances in simulation of gas-liquid reactors using a CFD-PBM coupled approach

In bubbly flow simulations, bubble size distribution is an important factor in determination of hydrodynamics. Beside hydrodynamics, it is crucial in the prediction of interfacial area available for mass transfer and in the prediction of reaction rate in gas-liquid reactors such as bubble columns. Solution of population balance equations is a method which can help to model the size distribution by considering continuous bubble coalescence and breakage. Therefore, in Computational Fluid Dynamic simulations it is necessary to couple CFD and Population Balance Model (CFD-PBM) to get reliable distribution. In the current work a CFD-PBM coupled model is implemented as FORTRAN subroutines in ANSYS CFX 10 and it has been tested for bubbly flow. This model uses the idea of Multi Phase Multi Size Group approach which was previously presented by Sha et al. (2006) [18]. The current CFD-PBM coupled method considers inhomogeneous flow field for different bubble size groups in the Eulerian multi-dispersed phase systems. Considering different velocity field for bubbles can give the advantageof more accurate solution of hydrodynamics. It is also an improved method for prediction of bubble size distribution in multiphase flow compared to available commercial packages.

Características de tolerância à seca em genótipos de uma coleção nuclear de arroz de terras altas

Resumo:O objetivo deste trabalho foi avaliar características morfofisiológicas relacionadas à tolerância ao estresse hídrico em genótipos de uma coleção nuclear temática de arroz de terras altas, bem como identificar os materiais mais tolerantes. Foram avaliados 100 genótipos de arroz de terras altas em experimentos conduzidos com e sem estresse por deficiência hídrica. Os genótipos tenderam a aumentar o número de dias para o florescimento (FLO) e a diminuir a altura (ALT), na condição de estresse, mas manifestaram ampla variação de comportamento. A esterilidade das espiguetas (EST) foi a característica mais importante para a seleção, nas duas condições de cultivo, em razão de sua elevada correlação negativa com a produtividade. O número de perfilhos não diferiu entre os genótipos na condição sem estresse, mas houve diferença significativa sob estresse hídrico. Os genótipos Ligeiro e Canela de Ferro apresentaram baixos índices de susceptibilidade à seca (ISS), mas baixa produtividade em ambas as condições de cultivo; já os materiais Catetão, Jatobá e Arroz do Maranhão apresentaram elevada produtividade sob estresse e valores de ISS relativamente baixos. EST, FLO, ALT e ISS são características morfofisiológicas relacionadas à tolerância à seca, e os genótipos Catetão, Jatobá e Arroz do Maranhão podem constituir boas fontes de genes para tolerância à seca em programas de melhoramento.

Guiding ligands to nuclear receptors.

Retinoic acid-the active metabolite of vitamin A-influences biological processes by activating the retinoic acid receptor (RAR). In this issue, Schug et al. (2007) demonstrate that retinoic acid also activates the peroxisome proliferator-activated receptor beta/delta (PPARbeta/delta). Remarkably, retinoic acid signaling through RAR or PPARbeta/delta-which depends on cytoplasmic retinoic acid transporters-commits the cell to opposite fates, apoptosis or survival, respectively.

Turvallisuustoimintojen käyttö ydinvoimalaitoksilla

Tässä diplomityössä tarkastellaan turvallisuustoiminto-käsitteen määrittelyä ja käyttöä osana ydinvoimalaitosten turvallisuuden varmistamista. Työssä kuvataan paine- ja kiehutusvesilaitosten toiminnan yleispiirteet, sekä Teollisuuden Voima Oy:n (TVO) laitosten Olkiluoto 1 & 2 sekä Olkiluoto 3 tarkempi turvallisuustoiminta turvallisuusjärjestelmien ja -automaation osalta. Työssä esitellään eräs tapa määrittää turvallisuustoimintoja. Malli perustuu hierarkkiseen rakenteeseen, jossa ylimpänä ovat laitostason turvallisuustoiminnot ja alimpana turvallisuustoimintoihin osallistuvien laitteiden ja niiden osien toiminnot. Turvallisuustoimintoja on mahdollista käyttää ydinvoimalaitoksen turvallisuusluokituksen tekemiseen ja perustelemiseen. Turvallisuustoiminto kertoo suoraan luokiteltavan kohteen turvallisuusmerkityksen. Kohteen turvallisuusmerkityksen selvittäminen, eli liittäminen turvallisuustoimintoon, voi olla vaikeaa. Turvallisuustoimintoja on myös mahdollista käyttää laitoksen turvallisuusautomaation riittävän varmistamisen (mm. redundanttisuus, diversiteetti ja erotus) osoittamiseen erityisesti ohjelmoitavan automaation yhteydessä. Turvallisuustoimintoja voidaan hyödyntää laitoksen hätätilanneohjeiden kehittämisessä ja myös laitoksenmuun turvallisuusdokumentaation selkeyttämisessä. Työn tuloksena kehitettiin käyville laitoksille (OL1 & 2) aikaisempaa kattavammat turvallisuustoiminnot. Lisäksi tarkasteltiin rakenteilla olevalle laitokselle (OL3) määriteltyjä turvallisuustoimintoja.

Procés de patrimonialització cultural de la central nuclear de Lemoiz (Bizkaia)

El propòsit central d’aquest treball és el de plantejar un procés d’activació del patrimoni cultural i històric, concretament el de la Central Nuclear de Lemoiz (Biscaia). Si la central fos declarada patrimoni industrial i històric es podria establir un punt de partida per a la resolució d’una situació complexa a nivell social, polític, urbanístic i medi-ambiental com és l’existència de la central nuclear

Flow phenomena, heat and mass transfer in microchannel reactors

The studies of flow phenomena, heat and mass transfer in microchannel reactors are beneficial to estimate and evaluate the ability of microchannel reactors to be operated for a given process reaction such as Fischer-Tropsch synthesis. The flow phenomena, for example, the flow regimes and flow patterns in microchannel reactors for both single phase and multiphase flow are affected by the configuration of the flow channel. The reviews of the previous works about the analysis of related parameters that affect the flow phenomena are shown in this report. In order to predict the phenomena of Fischer-Tropsch synthesis in microchannel reactors, the 3-dimensional computational fluid dynamic simulation with commercial software package FLUENT was done to study the flow phenomena and heat transfer for gas phase Fischer-Tropsch products flow in rectangular microchannel with hydraulic diameter 500 ¿m and length 15 cm. Numerical solution with slip boundary condition was used in the simulation and the flowphenomena and heat transfer were determined.

In vivo nuclear translocation of mineralocorticoid and glucocorticoid receptors in rat kidney: differential effect of corticosteroids along the distal tubule.

Aldosterone and corticosterone bind to mineralocorticoid (MR) and glucocorticoid receptors (GR), which, upon ligand binding, are thought to translocate to the cell nucleus to act as transcription factors. Mineralocorticoid selectivity is achieved by the 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) that inactivates 11β-hydroxy glucocorticoids. High expression levels of 11β-HSD2 characterize the aldosterone-sensitive distal nephron (ASDN), which comprises the segment-specific cells of late distal convoluted tubule (DCT2), connecting tubule (CNT), and collecting duct (CD). We used MR- and GR-specific antibodies to study localization and regulation of MR and GR in kidneys of rats with altered plasma aldosterone and corticosterone levels. In control rats, MR and GR were found in cell nuclei of thick ascending limb (TAL), DCT, CNT, CD cells, and intercalated cells (IC). GR was also abundant in cell nuclei and the subapical compartment of proximal tubule (PT) cells. Dietary NaCl loading, which lowers plasma aldosterone, caused a selective removal of GR from cell nuclei of 11β-HSD2-positive ASDN. The nuclear localization of MR was unaffected. Adrenalectomy (ADX) resulted in removal of MR and GR from the cell nuclei of all epithelial cells. Aldosterone replacement rapidly relocated the receptors in the cell nuclei. In ASDN cells, low-dose corticosterone replacement caused nuclear localization of MR, but not of GR. The GR was redistributed to the nucleus only in PT, TAL, early DCT, and IC that express no or very little 11β-HSD2. In ASDN cells, nuclear GR localization was only achieved when corticosterone was replaced at high doses. Thus ligand-induced nuclear translocation of MR and GR are part of MR and GR regulation in the kidney and show remarkable segment- and cell type-specific characteristics. Differential regulation of MR and GR may alter the level of heterodimerization of the receptors and hence may contribute to the complexity of corticosteroid effects on ASDN function.

Aplicações da tomografia de ressonância magnética nuclear como método não-destrutivo para avaliar os efeitos de injúrias mecânicas em goiabas 'Paluma' e 'Pedro Sato'

Objetivou-se determinar o potencial do uso da tomografia de ressonância magnética, como método não-destrutivo, para avaliar os efeitos das injúrias mecânicas em goiabas. Foram utilizados frutos no estádio de maturação "de vez" das cultivares Paluma e Pedro Sato. Na injúria por impacto, os frutos foram deixados cair, em queda livre, de uma altura de 1,20 m, sofrendo dois impactos, em lados opostos de sua porção equatorial. Na injúria por compressão, os frutos foram submetidos a um peso de 29,4 N, por 15 minutos. Para a injúria por corte, foram efetuados dois cortes, no sentido longitudinal dos frutos, de exatamente 30 mm de comprimento por 2 mm de profundidade. Os frutos injuriados foram armazenados sob condições de ambiente (22 ± 2 °C e 40 %UR). Foram realizadas análises com tomógrafo de ressonância magnética Varian Inova de 2 Tesla. As imagens foram obtidas a partir da detecção dos prótons de hidrogênio (¹H). Para cada fruto, foram obtidos tomogramas simétricos a partir do centro do fruto. A tomografia de ressonância magnética nuclear mostrou-se uma ferramenta eficaz na detecção de injúrias internas de frutos. O estresse físico causado pelo impacto produziu um colapso interno nos lóculos desses frutos (internal bruising), levando à perda da integridade celular e a conseqüente liquefação dos tecidos placentários. A cultivar Pedro Sato mostrou uma suscetibilidade maior à injúria por impacto que a 'Paluma'. A injúria por compressão tornou-se mais evidente no pericarpo externo do fruto, de ambas as cultivares. A injúria por corte levou a lignificação dos tecidos no local injuriado e deformações superficiais devido à perda acentuada de matéria fresca no local da lesão, evidentes no sexto dia de avaliação.

Different concentrations of Mg++ ions affect nuclear matrix protein distribution during thermal stabilization of isolated nuclei.

The nuclear matrix, a proteinaceous network believed to be a scaffolding structure determining higher-order organization of chromatin, is usually prepared from intact nuclei by a series of extraction steps. In most cell types investigated the nuclear matrix does not spontaneously resist these treatments but must be stabilized before the application of extracting agents. Incubation of isolated nuclei at 37C or 42C in buffers containing Mg++ has been widely employed as stabilizing agent. We have previously demonstrated that heat treatment induces changes in the distribution of three nuclear scaffold proteins in nuclei prepared in the absence of Mg++ ions. We studied whether different concentrations of Mg++ (2.0-5 mM) affect the spatial distribution of nuclear matrix proteins in nuclei isolated from K562 erythroleukemia cells and stabilized by heat at either 37C or 42C. Five proteins were studied, two of which were RNA metabolism-related proteins (a 105-kD component of splicing complexes and an RNP component), one a 126-kD constituent of a class of nuclear bodies, and two were components of the inner matrix network. The localization of proteins was determined by immunofluorescent staining and confocal scanning laser microscope. Mg++ induced significant changes of antigen distribution even at the lowest concentration employed, and these modifications were enhanced in parallel with increase in the concentration of the divalent cation. The different sensitivity to heat stabilization and Mg++ of these nuclear proteins might reflect a different degree of association with the nuclear scaffold and can be closely related to their functional or structural role.

Validation Studies of Thermal-hydraulic Code for Safety Analysis of Nuclear Power Plants

This thesis gives an overview of the validation process for thermal hydraulic system codes and it presents in more detail the assessment and validation of the French code CATHARE for VVER calculations. Three assessment cases are presented: loop seal clearing, core reflooding and flow in a horizontal steam generator. The experience gained during these assessment and validation calculations has been used to analyze the behavior of the horizontal steam generator and the natural circulation in the geometry of the Loviisa nuclear power plant. The cases presented are not exhaustive, but they give a good overview of the work performed by the personnel of Lappeenranta University of Technology (LUT). Large part of the work has been performed in co-operation with the CATHARE-team in Grenoble, France. The design of a Russian type pressurized water reactor, VVER, differs from that of a Western-type PWR. Most of thermal-hydraulic system codes are validated only for the Western-type PWRs. Thus, the codes should be assessed and validated also for VVER design in order to establish any weaknesses in the models. This information is needed before codes can be used for the safety analysis. Theresults of the assessment and validation calculations presented here show that the CATHARE code can be used also for the thermal-hydraulic safety studies for VVER type plants. However, some areas have been indicated which need to be reassessed after further experimental data become available. These areas are mostly connected to the horizontal stem generators, like condensation and phase separation in primary side tubes. The work presented in this thesis covers a large numberof the phenomena included in the CSNI code validation matrices for small and intermediate leaks and for transients. Also some of the phenomena included in the matrix for large break LOCAs are covered. The matrices for code validation for VVER applications should be used when future experimental programs are planned for code validation.

Effect of Noncondensable Gases on Circulation of Primary Coolant in Nuclear Power Plants in Abnormal Situations

The present study focuses on two effects of the presence of a noncondensable gas on the thermal-hydraulic behavior of thecoolant of the primary circuit of a nuclear reactor in the VVER-440 geometry inabnormal situations. First, steam condensation with the presence of air was studied in the horizontal tubes of the steam generator (SG) of the PACTEL test facility. The French thermal-hydraulic CATHARE code was used to study the heat transfer between the primary and secondary side in conditions derived from preliminary experiments performed by VTT using PACTEL. In natural circulation and single-phase vapor conditions, the injection of a volume of air, equivalent to the totalvolume of the primary side of the SG at the entrance of the hot collector, did not stop the heat transfer from the primary to the secondary side. The calculated results indicate that air is located in the second half-length (from the mid-length of the tubes to the cold collector) in all the tubes of the steam generator The hot collector remained full of steam during the transient. Secondly, the potential release of the nitrogen gas dissolved in the water of the accumulators of the emergency core coolant system of the Loviisa nuclear power plant (NPP) was investigated. The author implemented a model of the dissolution and release ofnitrogen gas in the CATHARE code; the model created by the CATHARE developers. In collaboration with VTT, an analytical experiment was performed with some components of PACTEL to determine, in particular, the value of the release time constant of the nitrogen gas in the depressurization conditions representative of the small and intermediate break transients postulated for the Loviisa NPP. Such transients, with simplified operating procedures, were calculated using the modified CATHARE code for various values of the release time constant used in the dissolution and release model. For the small breaks, nitrogen gas is trapped in thecollectors of the SGs in rather large proportions. There, the levels oscillate until the actuation of the low-pressure injection pumps (LPIS) that refill the primary circuit. In the case of the intermediate breaks, most of the nitrogen gas is expelled at the break and almost no nitrogen gas is trapped in the SGs. In comparison with the cases calculated without taking into account the release of nitrogen gas, the start of the LPIS is delayed by between 1 and 1.75 h. Applicability of the obtained results to the real safety conditions must take into accountthe real operating procedures used in the nuclear power plant.