380 research outputs found
Diversidade molecular entre populações de Spodoptera frugiperda no Brasil avaliada por marcadores AFLP.
O objetivo deste trabalho foi avaliar a diversidade molecular, por meio de marcadores AFLP, de seis populações de Spodoptera frugiperda coletadas na cultura do milho, em diferentes regiões geográficas do Brasil. O DNA foi extraído de lagartas de quarto instar, e as reações de AFLP foram realizadas com sete combinações de oligonucleotídeos iniciadores. A partir das seis populações de S. frugiperda estudadas, foi identificado um grupo principal formado por três populações geneticamente mais relacionadas. As populações de S. frugiperda analisadas mostram alta variabilidade genética, com máximo de 58% de similaridade
A split-GFP tool reveals differences in the sub-mitochondrial distribution of wt and mutant alpha-synuclein
Parkinson's disease (PD), the second most common neurodegenerative disorder, is characterized by dopaminergic neuronal loss that initiates in the substantia nigra pars compacta and by the formation of intracellular inclusions mainly constituted by aberrant \u3b1-synuclein (\u3b1-syn) deposits known as Lewy bodies. Most cases of PD are sporadic, but about 10% are familial, among them those caused by mutations in SNCA gene have an autosomal dominant transmission. SNCA encodes \u3b1-syn, a small 140-amino acids protein that, under physiological conditions, is mainly localized at the presynaptic terminals. It is prevalently cytosolic, but its presence has been reported in the nucleus, in the mitochondria and, more recently, in the mitochondria-associated ER membranes (MAMs). Whether different cellular localizations may reflect specific \u3b1-syn activities is presently unclear and its action at mitochondrial level is still a matter of debate. Mounting evidence supports a role for \u3b1-syn in several mitochondria-derived activities, among which maintenance of mitochondrial morphology and modulation of complex I and ATP synthase activity. \u3b1-syn has been proposed to localize at the outer membrane (OMM), in the intermembrane space (IMS), at the inner membrane (IMM) and in the mitochondrial matrix, but a clear and comparative analysis of the sub-mitochondrial localization of WT and mutant \u3b1-syn is missing. Furthermore, the reasons for this spread sub-mitochondrial localization under physiological and pathological circumstances remain elusive. In this context, we decided to selectively monitor the sub-mitochondrial distribution of the WT and PD-related \u3b1-syn mutants A53T and A30P by taking advantage from a bimolecular fluorescence complementation (BiFC) approach. We also investigated whether cell stress could trigger \u3b1-syn translocation within the different mitochondrial sub-compartments and whether PD-related mutations could impinge on it. Interestingly, the artificial targeting of \u3b1-syn WT (but not of the mutants) to the mitochondrial matrix impacts on ATP production, suggesting a potential role within this compartment
Specific immunotherapy by the sublingual route for respiratory allergy
Specific immunotherapy is the only treatment able to act on the causes and not only on the symptoms of respiratory allergy. Sublingual immunotherapy (SLIT) was introduced as an option to subcutaneous immunotherapy (SCIT), the clinical effectiveness of which is partly counterbalanced by the issue of adverse systemic reactions, which occur at a frequency of about 0.2% of injections and 2-5% of the patients and may also be life-threatening. A large number of trials, globally evaluated by several meta-analyses, demonstrated that SLIT is an effective and safe treatment for allergic rhinitis and allergic asthma, severe reactions being extremely rare. The application of SLIT is favored by a good compliance, higher than that reported for SCIT, in which the injections are a major factor for noncompliance because of inconvenience, and by its cost-effectiveness. In fact, a number of studies showed that SLIT may be very beneficial to the healthcare system, especially when its effectiveness persists after treatment withdrawal because of the induced immunologic changes
Seismic response assessment and protection of statues and busts
Recent post-earthquake surveys carried out in Europe have shown that earthquake actions pose an immense threat to museums and their contents. For example, during the earthquake on 21 July 2017 in the island of Kos (Greece), severe and widespread damage on the city’s archaeological museum was reported (Figure 1). The earthquake extensively damaged the sculpture exhibition, where many pieces were dislocated, leaned against the walls, or overturned. Fortunately, the earthquake occurred when human visitors were not in the museum, since the damage to the exhibits varied from very light (minor fracturing) to severe (complete overturning and fracture of artefacts). In the case of heavy and slender sculptures, the overturning mechanism, apart from damaging the sculptures themselves, is a serious threat to other standing exhibits in the gallery and the visitors. It is, therefore, of paramount importance to have at our disposal methods and tools for characterising the seismic risk of museum artefacts and, where necessary, proposing cost-efficient protective measures. The study of the seismic vulnerability of museum artefacts, especially of slender, human-formed statues, is related to the research on the dynamic response of rocking rigid blocks. The dynamic characteristics of the hosting structures are also important. This is evident from the fact that, on many occasions, damage to the structure was reported leaving the exhibits intact and vice-versa. Although the problem is coupled, it can be studied looking separately at the structure and its contents, provided that the contents are not attached to the building. The seismic response of building contents is a topic of growing interest, since it is directly related to seismic loss assessment and earthquake community resilience. Building contents can be either attached to the structure, or may consist of objects that are simply standing. Museum exhibits belong to the latter category, while free-standing components are often studied as rocking objects and hence their response is sensitive to acceleration and velocity-based quantities and also to their geometry. Today, there is lack of standards, while the existing approaches are general in concept and do not sufficiently address the variety of rocking objects. The problem becomes more complicated when it comes to priceless objects such as museum artefacts where more refined and targeted studies are required for understanding their seismic response and also for proposing rapid tools for assessing their seismic risk. The paper presents an extensive experimental campaign on the seismic response of artefacts, with emphasis on statues and busts. The tests took place in the framework of SEREME project (Seismic Resilience of Museum Contents) at the AZALEE seismic simulator of CEA in Saclay, Paris under the auspices of the SERA project. The aim is to understand the seismic response of statues and busts and then develop novel and cost-effective risk mitigation schemes for improving the seismic resilience of museum valuable contents. The study is focused on the investigation of the seismic response of two real-scale marble roman statues and three busts of three roman emperors standing on pedestals of different types and size. Both isolated and non-isolated artefacts are considered, while two new and highly efficient base isolation systems, tailored to art objects, will be tested. The first isolator is a pendulum-based system, while the second utilizes Shape Memory Alloy
wires. Furthermore, the paper examines the importance of the hosting building, i.e. building type and story. Specifically tailored, numerical models of varying complexity, for single and two-block rocking systems, were developed for the needs of this study and are also assessed against the experimental results
Superhumps in Cataclysmic Binaries. XXIII. V442 Ophiuchi and RX J1643.7+3402
We report the results of long observing campaigns on two novalike variables:
V442 Ophiuchi and RX J1643.7+3402. These stars have high-excitation spectra,
complex line profiles signifying mass loss at particular orbital phases, and
similar orbital periods (respectively 0.12433 and 0.12056 d). They are
well-credentialed members of the SW Sex class of cataclysmic variables. Their
light curves are also quite complex. V442 Oph shows periodic signals with
periods of 0.12090(8) and 4.37(15) days, and RX J1643.7+3402 shows similar
signals at 0.11696(8) d and 4.05(12) d. We interpret these short and long
periods respectively as a "negative superhump" and the wobble period of the
accretion disk. The superhump could then possibly arise from the heating of the
secondary (and structures fixed in the orbital frame) by inner-disk radiation,
which reaches the secondary relatively unimpeded since the disk is not
coplanar.
At higher frequencies, both stars show another type of variability:
quasi-periodic oscillations (QPOs) with a period near 1000 seconds. Underlying
these strong signals of low stability may be weak signals of higher stability.
Similar QPOs, and negative superhumps, are quite common features in SW Sex
stars. Both can in principle be explained by ascribing strong magnetism to the
white dwarf member of the binary; and we suggest that SW Sex stars are
borderline AM Herculis binaries, usually drowned by a high accretion rate. This
would provide an ancestor channel for AM Hers, whose origin is still
mysterious.Comment: PDF, 41 pages, 4 tables, 16 figures; accepted, in press, to appear
December 2002, PASP; more info at http://cba.phys.columbia.edu
Correction to: Human behavior and Homo-mammal interactions at the first European peopling: new evidence from the Pirro Nord site (Apricena, Southern Italy)
In the original publication of this article, one of the author names was incorrectly captured. The first name should be Razika, then family name should be Chelli–Cheheb
Superhumps in Cataclysmic Binaries. XXV. q_crit, epsilon(q), and Mass-Radius
We report on successes and failures in searching for positive superhumps in
cataclysmic variables, and show the superhumping fraction as a function of
orbital period. Basically, all short-period systems do, all long-period systems
don't, and a 50% success rate is found at P_orb=3.1+-0.2 hr. We can use this to
measure the critical mass ratio for the creation of superhumps. With a
mass-radius relation appropriate for cataclysmic variables, and an assumed mean
white-dwarf mass of 0.75 M_sol, we find a mass ratio q_crit=0.35+-0.02.
We also report superhump studies of several stars of independently known mass
ratio: OU Virginis, XZ Eridani, UU Aquarii, and KV UMa (= XTE J1118+480). The
latter two are of special interest, because they represent the most extreme
mass ratios for which accurate superhump measurements have been made. We use
these to improve the epsilon(q) calibration, by which we can infer the elusive
q from the easy-to-measure epsilon (the fractional period excess of P_superhump
over P_orb). This relation allows mass and radius estimates for the secondary
star in any CV showing superhumps. The consequent mass-radius law shows an
apparent discontinuity in radius near 0.2 M_sol, as predicted by the disrupted
magnetic braking model for the 2.1-2.7 hour period gap. This is effectively the
"empirical main sequence" for CV secondaries.Comment: PDF, 45 pages, 9 tables, 12 figures; accepted, in press, to appear
November 2005, PASP; more info at http://cba.phys.columbia.edu
Climatização especifica de maternidade suína: avaliação etológica de fêmeas lactantes.
The experiment was carried out during the summer at UNESP in Botucatu. Eight females swines of the Landrace and Large White breed were randomly assigned according to the order of calving. The behavior was evaluated in the first week of lactation in the morning, afternoon and night periods. The environment of the maternity was sealed by plastic canvas. For the climatization were used six fans and two water sprinklers on the roof. Environmental temperatures were monitored by dry / wet bulb thermometers and black globe (Tg) with readings every five minutes, over the course of five days. The body temperature of the animals was measured with the aid of the digital thermometer. The environments with enrichment and control were compared, and the behavior of the females was performed with the aid of an etogram. The behavior of the animals was evaluated using the chi-square test (X²), using the FREQ procedure of SAS version 9.1.2 (SAS Inst. Inc., Cary, NC). Litter, stereotyped, breathing, feeding, water consumption and movement differed statically among treatments, with a significant improvement in the well-being of the females in the climatization environment, mainly due to the decrease in the ambient temperature, where the temperature averages in the climatized area were of 17 and 18ºC and 32, 34ºC and control, with lower respiratory frequencies, with averages of 38 and 79 beats per minute and improved breathing in the three periods. It is concluded that the use of ventilators internally and sprinklers of water on the roof externally, improved the thermal comfort and the welfare of the swine.O experimento foi realizado durante o verão na UNESP campus Botucatu. Foram utilizadas oito fêmeas da raça Landrace e Large White, distribuídas aleatoriamente de acordo com a ordem de parição. O comportamento foi avaliado na primeira semana de lactação nos períodos da manhã, tarde e noite. O ambiente da maternidade foi vedado por lona plástica. Para a climatização foram utilizados seis ventiladores e dois aspersores de água no telhado. As temperaturas ambientais foram monitoradas através de termômetros de bulbo seco/úmido e globo negro (Tg) com leituras a cada cinco minutos, no decorrer dos cinco dias. A temperatura corporal dos animais foi medida com o auxílio do termômetro digital. Foram comparados os ambientes com enriquecimento e controle, sendo a análise do comportamento das fêmeas realizada com o auxílio de um etograma. O comportamento dos animais foi avaliado através do teste de Qui-Quadrado (X²), através do procedimento FREQ do SAS versão 9.1.2 (SAS Inst. Inc., Cary, NC). Os comportamentos lúdicos, estereotipados, ofego, alimentação, consumo de água e movimentação diferiram estaticamente entre os tratamentos, com melhora significativa do bem-estar das matrizes no ambiente climatizado, principalmente pela diminuição da temperatura ambiental, onde as médias de temperatura na área climatizada foram de 17 e 18ºC e 32, 34ºC e controle, com menores frequências respiratórias, com médias de 38 e 79 batimentos por minuto e melhoria do ofego nos três períodos. Conclui-se que a utilização de ventiladores internamente e aspersores de água no telhado externamente, melhorou o conforto térmico e o bem-estar das fêmeas suínas paridas
Circular economy in biocomposite development: State-of-the-art, challenges and emerging trends
Biocomposites being environmentally-friendly alternative to synthetic composites are gaining increasing demand for various applications. Hence, biocomposite development should be integrated within a circular economy (CE) model to ensure a sustainable production that is simultaneously innocuous towards the environment. This review presents an overview of the state-of-the-art technologies for the adoption of the CE concept in biocomposite development. The study outlined the properties, environmental and economic impacts of biocomposites. A critical review of the life-cycle assessment of biocomposite for evaluating greenhouse gas emissions and carbon footprints was conducted. In addition, the opportunities and challenges pertaining to the implementation of CE have been discussed in detail. Recycling and utilisation of bio-based constituents were identified as the critical factors in embracing CE. Therefore, the development of innovative recycling technologies and an enhanced use of novel biocomposite constituents could lead to a reduction in material waste and environmental footprints. This article is one of the first studies to review the circularity of biocomposites in detail that will stimulate further research in enhancing the sustainability of these polymeric materials. © 202
Inactivation of citron kinase inhibits medulloblastoma progression by inducing apoptosis and cell senescence
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