Assessment of RNAi-induced silencing in banana (Musa spp.)

In plants, RNA- based gene silencing mediated by small RNAs functions at the transcriptional or post-transcriptional level to negatively regulate target genes, repetitive sequences, viral RNAs and/or transposon elements. Post-transcriptional gene silencing (PTGS) or the RNA interference (RNAi) approach has been achieved in a wide range of plant species for inhibiting the expression of target genes by generating double-stranded RNA (dsRNA). However, to our knowledge, successful RNAi-application to knock-down endogenous genes has not been reported in the important staple food crop banana

Assessing Tolerance to Heavy-Metal Stress in Arabidopsis thaliana Seedlings

The deposited book chapter is a post-print version and has been submitted to peer review.The deposited book chapter version contains attached the supplementary materials within the pdf.This publication hasn't any creative commons license associated.The deposited book chapter is part of the book series: "Environmental Responses in Plants: Methods and Protocols" (pp.197-208) published by Springer.Heavy-metal soil contamination is one of the major abiotic stress factors that, by negatively affecting plant growth and development, severely limit agricultural productivity worldwide. Plants have evolved various tolerance and detoxification strategies in order to cope with heavy-metal toxicity while ensuring adequate supply of essential micronutrients at the whole-plant as well as cellular levels. Genetic studies in the model plant Arabidopsis thaliana have been instrumental in elucidating such mechanisms. The root assay constitutes a very powerful and simple method to assess heavy-metal stress tolerance in Arabidopsis seedlings. It allows the simultaneous determination of all the standard growth parameters affected by heavy-metal stress (primary root elongation, lateral root development, shoot biomass, and chlorophyll content) in a single experiment. Additionally, this protocol emphasizes the tips and tricks that become particularly useful when quantifying subtle alterations in tolerance to a given heavy-metal stress, when simultaneously pursuing a large number of plant lines, or when testing sensitivity to a wide range of heavy metals for a single line.Fundação para a Ciência e a Tecnologia grants: (EXPL/AGR-PRO/1013/2013, SFRH/BPD/44640/2008); GREEN-it "Bioresources for Sustainability": (UID/Multi/04551/2013).info:eu-repo/semantics/publishedVersio

Aktivitas Sitotoksik Dari Ekstrak Bintang Ular (Ophiomastix Annulosa) Terhadap Perkembangan Awal Embrio Bulu Babi (Tripneustes Gratilla)

Penelitian di bidang alam bahari telah berkembang ditandai dengan ditemukannya substansi-substansi seperti sitotoksik, antimikroba, antifungi dan sebagainya yang dibutuhkan dalam penyediaan bahan-bahan farmasi. Penelitian ini bertujuan untuk mendeteksi ada tidaknya substansi sititoksik pada bintang ular Ophimastix annulosa dan menelusuri keberadaan senyawanya. Sampel diekstraksi dengan pelarut metanol, kemudian dipartisi menggunakan pelarut etil asetat, heksan dan kloroform. Tiap fraksi diuji pada sel telur bulu babi (Tripneustes gratilla) sebelum dan sesudah difertilisasi. Hasil pengamatan menunjukkan bahwa ekstrak metanolik O. annulosa dan ketiga fraksi (etil asetat, heksan dan kloroform) memiliki substans sitotoksik. keempat fraksi yang diuji mampu menghambat perkembangan sel telur dan embrio bulu babi. fraksi kloroform menunjukkan aktivitas sitotoksik tertinggi dibandingkan ketiga fraksi lainnya sehingga perlu dilakukan pemurnian lanjut untuk menemukan senyawa murni

Three photometric methods tested on ground-based data of Q 2237+0305

The Einstein Cross, Q~2237+0305, has been photometrically observed in four bands on two successive nights at NOT (La Palma, Spain) in October 1995. Three independent algorithms have been used to analyse the data: an automatic image decomposition technique, a CLEAN algorithm and the new MCS deconvolution code. The photometric and astrometric results obtained with the three methods are presented. No photometric variations were found in the four quasar images. Comparison of the photometry from the three techniques shows that both systematic and random errors affect each method. When the seeing is worse than 1.0", the errors from the automatic image decomposition technique and the Clean algorithm tend to be large (0.04-0.1 magnitudes) while the deconvolution code still gives accurate results (1{sigma} error below 0.04) even for frames with seeing as bad as 1.7". Reddening is observed in the quasar images and is found to be compatible with either extinction from the lensing galaxy or colour dependent microlensing. The photometric accuracy depends on the light distribution used to model the lensing galaxy. In particular, using a numerical galaxy model, as done with the MCS algorithm, makes the method less seeing dependent. Another advantage of using a numerical model is that eventual non-homogeneous structures in the galaxy can be modeled. Finally, we propose an observational strategy for a future photometric monitoring of the Einstein Cross.Comment: 9 pages, accepted for publication in A&

Diagnostic errors and reflective practice in medicine

Background: Adverse effects of medical errors have received increasing attention. Diagnostic errors account for a substantial fraction of all medical errors, and strategies for their prevention have been explored. A crucial requirement for that is better understanding of origins of medical errors. Research on medical expertise may contribute to that as far as it explains reasoning processes involved in clinical judgements. The literature has indicated the capability of critically reflecting upon one\'s own practice as a key requirement for developing and maintaining medical expertise throughout life. Objectives: This article explores potential relationships between reflective practice and diagnostic errors. Methods: A survey of the medical expertise literature was canducted. Origins of medical errors frequently reported in the literature were explored. The potential relationship between diagnostic errors and the several dimensions of reflective practice in medicine, brought to light by recent research, were theoretically explored. Results and Dissussion: Uncertainty and fallibility inherent to clinical judgements are discussed. Stages in the diagnostic reasoning process where errors could occur and their potential sources are highlighted, including the role of medical heuristics and biases. The authors discuss the nature of reflective practice in medicine, and explore whether and how the several behaviours and reasoning processes that constitute reflective practice could minimize diagnostic errors. Future directions for further research are discussed. They involve empirical research on the role of reflective practice in improving clinical reasoning and the development of educational strategies to enhancing reflective practice

Status of the BMV experiment

In this contribution we present the status of the BMV experiment whose goal is to measure the vacuum magnetic birefringence

Effects of an experimental resource pulse on the macrofaunal assemblage inhabiting seagrass macrophytodetritus

Physical disturbances and resource pulses are major structuring drivers of terrestrial and aquatic ecosystems. The accumulations of exported dead leaves from the Neptune grass, Posidonia oceanica (L.) Delile are ephemeral and highly dynamic detrital habitats offering food sources and shelter for vagile macrofauna community. These habitats are frequently subject to wind and storms which can add “new” detrital material to previous accumulations; these can be defined as resource pulses and could potentially impact the associated macrofauna. This study assesses the impact of an experimental resource pulse on the macrofauna associated with exported P. oceanica litter accumulations. The experimental design consisted of two pulse treatments (the addition of dead leaves with and without the associated fauna), and two controls (one procedural, and one total control), where the added material was left underwater for 14 days. Invertebrates then present in the sampled detritus were all identified and counted. Our data suggest that the responses of these invertebrates to resource pulses present intermediate characteristics between aquatic and terrestrial ecosystems responses. Inputting a moderate amount of dead P. oceanica leaves into experimental mesocosms had a non-negligible impact and rapidly affected the macrofauna community. Specialist detritivores species were boosted while herbivore/detritivore species dramatically decreased. Predators also showed a modest but significant density increase, demonstrating the fast propagation of the pulse response throughout the entire community and through several trophic levels. Strict hypoxia-tolerant species were also only observed in the treated mesocosms, indicating the strong influence of resource pulses on physico-chemical conditions occurring inside litter accumulations

Possible explanations for different surface quality in laser cutting with 1 micron and 10 microns beams

In laser　cutting　of　thick　steel　sheets,　quality　difference　is　observed　between　cut　surfaces　obtained　with 1 micron and 10 micron laser beams. This paper investigates physical mechanisms for this interesting and important problem of the wavelength dependence. First, striation generation process is described, based on a 3D structure of melt flow on a kerf front, which was revealed for the first time by our recent experimental observations. Two fundamental processes are suggested to explain the difference in the cut surface quality: destabilization of the melt flow in the central part of the kerf front and downward displacement of discrete melt accumulations along the side parts of the front. Then each of the processes is analyzed using a simplified analytical model. The results show that in both processes, different angular dependence of the absorptivity of the laser beam can result in the quality difference. Finally we propose use of radial polarization to improve the quality with the 1 micron wavelength

Bias and consistency in time delay estimation methods: case of the double quasar HE 1104-1805

We present a short re-evaluation of a recently published time delay estimate for the gravitational lens system HE 1104-1805 with emphasis on important methodological aspects: bias of the statistics, inconsistency of the methods and use of the purposeful selection of data points(or so-called "cleaning") at the preprocessing stage. We show how the inadequate use of simple analysis methods can lead to too strong conclusions. Our analysis shows that there are indications for the time delay in HE 1104-1805 to be between -0.9 and -0.7 years, but still with a large uncertainty.Comment: 5 pages, 5 figures, accepted as a Letter to the Editor in A&

Uji Aktivitas Larvasida Nyamuk Aedes Aegypti Dari Beberapa Ekstrak Ascidian

Dengue Hemorrhagic Fever (DHF) is a disease caused by virus through Aedesaegypti mosquitoes as the vector. The disease is spreading across the world andendanger and threaten human life. Measures in controlling the vector using the commonlarvaside “abate” are in adequate and less affective. The objectives of the research is tofind out larvaside extracted from three kinds of ascidian. The each ascidians (Polycarpaaurata, Didemnum molle and Rophalaea crassa) were extracted with ethanol, and thecrude extracts were subjected to larvasidal test by dissolving in water containing thelarvae. The remarkable extract activity was partition in ethyl acetate, hexane andbuthanol. The results show that extract of Polycarpa aurata has the highest activity. Theactivity of fractions show that ethyl acetate at 100 ppm reveals the highest mortality oflarvae 100% in 8 hours, followed by hexane fraction (12 hours) then buthanol fraction (18hours). All the fractions (Ethyl acetate, Hexane and Buthanol) could totality kill the larvaewithin 24 hours which is comparable to the abate