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Drones: Innovative Technology for Use in Precision Pest Management.
Arthropod pest outbreaks are unpredictable and not uniformly distributed within fields. Early outbreak detection and treatment application are inherent to effective pest management, allowing management decisions to be implemented before pests are well-established and crop losses accrue. Pest monitoring is time-consuming and may be hampered by lack of reliable or cost-effective sampling techniques. Thus, we argue that an important research challenge associated with enhanced sustainability of pest management in modern agriculture is developing and promoting improved crop monitoring procedures. Biotic stress, such as herbivory by arthropod pests, elicits physiological defense responses in plants, leading to changes in leaf reflectance. Advanced imaging technologies can detect such changes, and can, therefore, be used as noninvasive crop monitoring methods. Furthermore, novel methods of treatment precision application are required. Both sensing and actuation technologies can be mounted on equipment moving through fields (e.g., irrigation equipment), on (un)manned driving vehicles, and on small drones. In this review, we focus specifically on use of small unmanned aerial robots, or small drones, in agricultural systems. Acquired and processed canopy reflectance data obtained with sensing drones could potentially be transmitted as a digital map to guide a second type of drone, actuation drones, to deliver solutions to the identified pest hotspots, such as precision releases of natural enemies and/or precision-sprays of pesticides. We emphasize how sustainable pest management in 21st-century agriculture will depend heavily on novel technologies, and how this trend will lead to a growing need for multi-disciplinary research collaborations between agronomists, ecologists, software programmers, and engineers
Educação e condição feminina em um tratado de Alexandre de Gusmão escrito na América Portuguesa no final do século XVII
Neste artigo apresentamos uma análise dos discursos acerca da educação e da condição feminina presentes na obra Arte de crear bem os filhos na idade da Puericia. Escrita na América Portuguesa, mas publicada inicialmente em Portugal no ano de 1685, a obra de autoria do padre jesuíta Alexandre de Gusmão (1629-1724) destinou seu último capítulo, “Do especial cuidado que se deve ter na criação das meninas”, para tratar das advertências necessárias à boa educação de raparigas. No contexto de produção da obra educativa proposta por Alexandre de Gusmão, queremos propor a análise de um conjunto de enunciados que colocam em evidência uma espécie de ordenamento das condições de vida e das orientações educativas de sujeitos infantis femininos. Inferimos que a propagação de obras de cunho moralista no espaço luso-brasileiro entre os séculos XVII e XVIII possibilitou a circulação de tais ordens enunciativas, influenciando, significativamente, o comportamento social da época. A partir de uma perspectiva histórica e filosófica, principalmente através de referenciais teóricos foucaultianos, entendemos que a obra foi um eficiente mecanismo que atuou na constituição discursiva de modelos específicos de educação para garantir a produção de um determinado tipo de sujeito infantil feminino. Notadamente, identificamos duas normativas que advertiam sobre a boa criação das meninas cristãs através das práticas de guarda e recolhimento.In this paper we present an analysis of the discourses about education and the female condition present in the work Arte de crear bem os filhos na Idade da Puericia [Art of raising children well at the age of childhood]. Written in the Portuguese America, but initially published in Portugal in 1685, the work by the Jesuit priest Alexandre de Gusmão (1629-1724) assigned its last chapter, “Of the special care that must be taken in raising girls”, to address the warnings necessary for the good upbringing of girls. In the context of production of the educational work proposed by Alexandre de Gusmão, we want to propose the analysis of a set of statements that put in evidence a kind of ordering of the living conditions and educational guidelines of female children. We infer that the propagation of works of a moralist nature in the Luso-Brazilian space between the 17th and 18th centuries enabled the circulation of such enunciative orders, significantly influencing the social behavior of the time. From a historical and philosophical perspective, mainly through Foucauldian theoretical references, we understand that the work was an efficient mechanism that acted in the discursive constitution on specific models of education to guarantee the production of a certain type of female child subject. Notably, we identified two regulations that warned about the good upbringing of Christian girls through the practices of guardianship and retreat
Peroxisome Proliferator-Activated Receptor Delta: A Conserved Director of Lipid Homeostasis through Regulation of the Oxidative Capacity of Muscle
The peroxisome proliferator-activated receptors (PPARs), which are ligand-inducible transcription factors expressed in a variety of tissues, have been shown to perform key roles in lipid homeostasis. In physiological situations such as fasting and physical exercise, one PPAR subtype, PPARδ, triggers a transcriptional program in skeletal muscle leading to a switch in fuel usage from glucose/fatty acids to solely fatty acids, thereby drastically increasing its oxidative capacity. The metabolic action of PPARδ has also been verified in humans. In addition, it has become clear that the action of PPARδ is not restricted to skeletal muscle. Indeed, PPARδ has been shown to play a crucial role in whole-body lipid homeostasis as well as in insulin sensitivity, and it is active not only in skeletal muscle (as an activator of fat burning) but also in the liver (where it can activate glycolysis/lipogenesis, with the produced fat being oxidized in muscle) and in the adipose tissue (by incrementing lipolysis). The main aim of this review is to highlight the central role for activated PPARδ in the reversal of any tendency toward the development of insulin resistance
Precipitation as the main driver of Neoglacial fluctuations of Gualas glacier, Northern Patagonian Icefield
© The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Climate of the Past 8 (2012): 519-534, doi:10.5194/cp-8-519-2012.Glaciers are frequently used as indicators of climate change. However, the link between past glacier fluctuations and climate variability is still highly debated. Here, we investigate the mid- to late-Holocene fluctuations of Gualas Glacier, one of the northernmost outlet glaciers of the Northern Patagonian Icefield, using a multi-proxy sedimentological and geochemical analysis of a 15 m long fjord sediment core from Golfo Elefantes, Chile, and historical documents from early Spanish explorers. Our results show that the core can be sub-divided into three main lithological units that were deposited under very different hydrodynamic conditions. Between 5400 and 4180 cal yr BP and after 750 cal yr BP, sedimentation in Golfo Elefantes was characterized by the rapid deposition of fine silt, most likely transported by fluvio-glacial processes. By contrast, the sediment deposited between 4130 and 850 cal yr BP is composed of poorly sorted sand that is free of shells. This interval is particularly marked by high magnetic susceptibility values and Zr concentrations, and likely reflects a major advance of Gualas glacier towards Golfo Elefantes during the Neoglaciation. Several thin silt layers observed in the upper part of the core are interpreted as secondary fluctuations of Gualas glacier during the Little Ice Age, in agreement with historical and dendrochronological data. Our interpretation of the Golfo Elefantes glaciomarine sediment record in terms of fluctuations of Gualas glacier is in excellent agreement with the glacier chronology proposed for the Southern Patagonian Icefield, which is based on terrestrial (moraine) deposits. By comparing our results with independent proxy records of precipitation and sea surface temperature, we suggest that the fluctuations of Gualas glacier during the last 5400 yr were mainly driven by changes in precipitation in the North Patagonian Andes.This research was supported by an EU FP6
Marie Curie Outgoing Fellowship to S.B. Cruise NBP0505 was
funded by the US National Science Foundation, Office of Polar
Programs grant number NSF/OPP 03-38137 to J. Anderson (Rice
University) and J. Smith Wellner (University of Houston). The
Cimar-7 Program was supported by the Chilean National Oceanographic
Committee (CONA, Grant C7F 01-10 to S. Pantoja)
Mitigating the risk of blackleg disease of canola using fungicide strategies
Non-Peer ReviewedBlackleg, the most widespread disease on canola on the prairies, has been managed mainly through use
of resistant cultivars in combination with crop rotation. Over the past few years, crop rotation has been
tightened in favor of canola production due largely to profitability considerations but this practice can
speed up changes in pathogen race structure that may lead to losses of resistance for some of the current
canola cultivars. In this study, fungicides strategies were assessed as a second line of defense for control
of blackleg and canola yield benefit in case when the variety resistance is overcome by the pathogen. In
2011, the fungicide Headline, Quadris, and Quilt were applied at 2-4 leaf stage and/or bolting to target
varying periods of infection at three locations on the prairies. On the susceptible cultivar Westar, an
early application (2-4 leaf) of Headline or Quadris reduced the disease at Carman, MB, but not at
Melfort or Vegreville relative to non-treated controls. None of the fungicide treatments increased canola
yield substantially either. The study will be continued for two more years at multiple locations across the
prairies
“Quando sahir de caza, arme-te com o signal da Cruz”: instruções para a rotina de um menino cristão em um manual pedagógico português do século XVIII
Este artigo tem por objetivo analisar certos enunciados religiosos para o cotidiano da infância masculina presentes no manual pedagógico Escola Nova, Christã, e Politica, Na qual se ensinão os primeiros rudimentos, que deve saber o Menino Christão, e se lhes dão regras para com facilidade, e em pouco tempo aprender a ler, escrever e contar. Publicada em Portugal inicialmente no ano de 1756 a obra de autoria de Francisco Luiz Ameno (1713-1793) foi registrada pelo pseudônimo de D. Leonor Thomasia de Sousa e Silva. Ao enquadrar o manual na categoria de Literatura de Comportamento Social, interessa-me, em particular, verificar as instruções que o autor prescreveu para a rotina de um menino cristão no contexto setecentista português. Nesse sentido, o conjunto das práticas recomendadas foram percebidas, aqui como mecanismos para a produção de máximas morais e de comportamentos socialmente desejáveis, que constituíram modos específicos de ser menino infantil em Portugal no século XVIII
Profile instabilities of the millisecond pulsar PSR J1022+1001
We present evidence that the integrated profiles of some millisecond pulsars
exhibit severe changes that are inconsistent with the moding phenomenon as
known from slowly rotating pulsars. We study these profile instabilities in
particular for PSR J1022+1001 and show that they occur smoothly, exhibiting
longer time constants than those associated with moding. In addition, the
profile changes of this pulsar seem to be associated with a relatively
narrow-band variation of the pulse shape. Only parts of the integrated profile
participate in this process which suggests that the origin of this phenomenon
is intrinsic to the pulsar magnetosphere and unrelated to the interstellar
medium. A polarization study rules out profile changes due to geometrical
effects produced by any sort of precession. However, changes are observed in
the circularly polarized radiation component. In total we identify four
recycled pulsars which also exhibit instabilities in the total power or
polarization profiles due to an unknown phenomenon (PSRs J1022+1001,
J1730-2304, B1821-24, J2145-0750).
The consequences for high precision pulsar timing are discussed in view of
the standard assumption that the integrated profiles of millisecond pulsars are
stable. As a result we present a new method to determine pulse times-of-arrival
that involves an adjustment of relative component amplitudes of the template
profile. Applying this method to PSR J1022+1001, we obtain an improved timing
solution with a proper motion measurement of -17 \pm 2 mas/yr in ecliptic
longitude. Assuming a distance to the pulsar as inferred from the dispersion
measure this corresponds to an one-dimensional space velocity of 50 km/s.Comment: 29 pages, 12 figures, accepted for publication in Ap
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