6,859 research outputs found

    A new prey record and range extension for Hyperaspis paludicola Schwarz and a new prey record for Microweisea misella (LeConte) (Coleoptera: Coccinellidae)

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    The miscanthus mealybug, Miscanthicoccus miscanthi (Takahashi) (Hemiptera: Pseudococcidae), is newly reported as prey for the lady beetle Hyperaspis paludicola Schwarz (Coleoptera: Coccinellidae) at the Regan National Airport, Washington, DC (northern range extension). A new armored scale prey, Diaspidiotus ancyclus (Putnam) (Hemiptera: Diaspididae), for the lady beetle Microweisea misella (LeConte) (Coleoptera: Coccinellidae) is recorded. A range extension for Hyperaspis paludicola is reported

    Utilizing Astrometric Orbits to Obtain Coronagraphic Images

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    We present an approach for utilizing astrometric orbit information to improve the yield of planetary images and spectra from a follow-on direct detection mission. This approach is based on the notion-strictly hypothetical-that if a particular star could be observed continuously, the instrument would in time observe all portions of the habitable zone so that no planet residing therein could be missed. This strategy could not be implemented in any realistic mission scenario. But if an exoplanet's orbit is known from astrometric observation, then it may be possible to plan and schedule a sequence of imaging observations that is the equivalent of continuous observation. A series of images-optimally spaced in time-could be recorded to examine contiguous segments of the orbit. In time, all segments would be examined, leading to the inevitable detection of the planet. In this paper, we show how astrometric orbit information can be used to construct such a sequence. Using stars from astrometric and imaging target lists, we find that the number of observations in this sequence typically ranges from 2 to 7, representing the maximum number of observations required to find the planet. The probable number of observations ranges from 1.5 to 3.1. This is a dramatic improvement in efficiency over previous methods proposed for utilizing astrometric orbits. We examine how the implementation of this approach is complicated and limited by operational constraints. We find that it can be fully implemented for internal coronagraph and visual nuller missions, with a success rate approaching 100%. External occulter missions will also benefit, but to a lesser degree.Comment: 28 pages, 14 figures, submitted to PAS

    Modified optimal control pilot model for computer-aided design and analysis

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    This paper presents the theoretical development of a modified optimal control pilot model based upon the optimal control model (OCM) of the human operator developed by Kleinman, Baron, and Levison. This model is input compatible with the OCM and retains other key aspects of the OCM, such as a linear quadratic solution for the pilot gains with inclusion of control rate in the cost function, a Kalman estimator, and the ability to account for attention allocation and perception threshold effects. An algorithm designed for each implementation in current dynamic systems analysis and design software is presented. Example results based upon the analysis of a tracking task using three basic dynamic systems are compared with measured results and with similar analyses performed with the OCM and two previously proposed simplified optimal pilot models. The pilot frequency responses and error statistics obtained with this modified optimal control model are shown to compare more favorably to the measured experimental results than the other previously proposed simplified models evaluated

    Value for money in schools: Report for the Audit Office

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    In January 2008, the Audit Commission appointed FGS, in association with the University of Southampton, to carry out a review in relation to Value for Money (VfM) in schools. Examining VfM in schools requires a detailed consideration of both the inputs and the outputs relating to the education system; in other words, the costs and benefits associated with schools. In this context, inputs are relatively straightforward to express: staffing typically represents around 70% of school costs, with the remainder comprising of operating and maintenance expenditure. However, defining the outputs from schools (pupil outcomes) is an altogether more complex task. The most tangible measure of pupil outcomes is the results they achieve in examinations. Even so, both in the UK and overseas, it is widely recognised that pupils’ levels of achievement are influenced by a range of factors other than the quality of schooling they receive (for example, their family background or their track record of achievement at earlier stages of their education). Put simply, pupils’ current levels of attainment are likely to be enhanced if they have a high level of prior educational attainment, and therefore schools may make a less significant contribution to student outcomes. In assessing the value for money which schools deliver through their day-to-day activities, it is therefore necessary to take account of the progress pupils make in their time at school (or ‘value added’ by the school), rather than just their levels of attainment, which are influenced by a host of factors other than schooling. <br/

    Identifying and managing asbestiform minerals in geological collections

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    Asbestos is widely recognised as a serious hazard, and its industrial use is now banned within the UK, and EU, and strict regulations govern the use of older manufactured materials which may contain asbestos. However, asbestos is also a natural geological material, and may occur in museum collections as minerals or constituents of rock specimens. In the UK the Control of Asbestos Regulations 2012 (CAR 2012) provides the legal framework for the safe identification, use and disposal of asbestos. However, these regulations, and other EU regulations, provide no specific guidance on dealing with potentially asbestos-containing natural materials. CAR 2012 specifies just six asbestos minerals although a number of other minerals in museum collections are known to have asbestiform structures and be hazard-ous, including other amphiboles, and the zeolite erionite. Despite the lack of specific guid-ance, museums must comply with CAR 2012, and this paper outlines the professional ad-vice, training and procedures which may be needed for this. It provides guidance on identifi-cation of potential asbestos-bearing specimens and on procedures to document them and store them for future use, or to prepare them for professional disposal. It also makes sug-gestions how visitors, employees and others in a museum can be protected from asbestos as incoming donations and enquiries, managed in the event of an emergency, and safely included in displays

    Studies on the nucleophilic substitution reactions of N-oxygenated quinoxalinones

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    The conversion of 4- acetoxy -6- chloro -1, 2- dihydro -2- oxo -3- phenylquinoxalinium perchlorate into the ring -contracted product 1- benzoyl-6- chlorobenzimidazol -2 -one and 6, 8-dichloro-7- hydroxyquinoxalin -2(1H) -one, by treatment with water, is described and mechanisms accounting for these rearrangements are discussed. The attempted base - catalysed ring contraction of 4- acetoxy -6- chloro -1, 2- dihydro -2- oxo -3- phenylquinoxalinium perchlorate using triethylamine and hydroxide ion as catalysts proved unsuccessful.The reactions of a series of 4- acetoxy -1, 2- dihydro -2- oxo -3- phenylquinoxalinium perchlorates with morpholine have been investigated. Mechanisms accounting for the formation of the products of morpholinesubstitution and /or ring contraction are discussed.The scope of the nucleophilic substitution reactions of 4 -Nac etoxy- 6 -chlor o- l - methyl -3- morpholino -3 -phenylquinoxalin- 2( 1H)- one has been investigated. Reaction to afford 7- substituted quinoxalin-2(1H)- ones has been demonstrated with chloride, bromide, azide, cyanate, thiocyanate and hydride ions. Reaction with benzenesulphinate and cyanide ion gave unresolved mixtures of 5- and 7- substituted quinoxalin2(1H) -ones. Reaction with iodide and fluoride ions and with hydrobromic acid gave 6- chloro-1- methyl -3- phenylquinoxalin -2(1H) -one. Mechanisms accounting for the formation of these products are discussed. Attempted reaction with phenoxide and acetylacetonate ions, diethylamine and ethyl magnesium bromide proved unsuccessful.Treatment of 4-N-acetoxy-6-chloro-l- methyl -3- morpholino -3- phenylquinoxalin -2(1H) -one with boron trifluoride -etherate in dioxan gave di(6- chloro -1, 2- dihydro -1- methyl -2- oxo -3- phenylquinoxalin -7 -yl) ether. A mechanism to account for this rearrangement is proposed.A series of 3- cyanoquinoxalin -2(1H) -one 4- oxides has been prepared by the base -catalysed cyclisation of the appropriate 2- nitro- a- cyanoacetanilides. The reactions of these compounds and those of 3- cyano -lmethylquinoxalin -2(1H) -one 4- oxide, 3- benzoylquinoxalin -2(1H) -one 4 -oxide and 3- aminoquinoxalin -2(1H) -one 4- oxide with acetyl chloride in acetic acid have been investigated. Mechanisms accounting for the formation of the products of these reactions are proposed and discussed. The reactions of selected 3- cyanoquinoxalin -2(1H) -ones with acetic anhydride have also been investigated and mechanisms are proposed to account for the mode of reaction observed.A series of 1- hydroxyquinoxaline -2, 3(1H, 4H)- diones has been prepared by base -catalysed conversion of the appropriate 2- nitro -acyanoacetanilides. The attempted base -catalysed syntheses of 1- hydroxy6- methylquinoxaline -2, 3(1H, 4H) -dione and 6, 7- dimethyl- 1 -hydr oxyquinoxaline-2, 3(1H, 4H) -dione from both the corresponding 2- nitro -acyanoacetanilides and 3- cyanoquinoxalin -2(1H) -one 4- oxides proved unsuccessful. The reactions of the 1- hydroxyquinoxaline -2, 3( 1H, 4H)- diones and a series of 4- alkyl-l-hydr oxyquinoxaline-2, 3(1H, 4H)- diones with acetyl chloride in acetic acid and with acetic anhydride have been investigated and mechanisms are discussed to account for the formation of the products of substitution and ring- contraction obtained.A series of 3- cyano -l- hydroxyquinoxaline -2(1H) -one 4- oxides has been prepared by the base -catalysed reaction of ethyl cyanoacetate with the appropriate benzofuroxan. The base -catalysed conversion of the 3- cyano- 1- hydroxyquinoxaline -2(1H) -one 4- oxides into 1, 4-di-N-hydr oxyquinoxaline-2, 3(1H, 4H)- diones is described and mechanisms accounting for the formation of these products are discussed.The reactions of 1, 4- di- N- hydroxyquinoxaline -2, 3(1H, 4H)- diones with acetyl chloride and acetyl bromide in acetic acid have been investigated. Mechanisms are proposed for the formation of the products of substitution and ring- contraction obtained. The attempted reaction of 1, 4- dihydroxyquinoxaline-2, 3(1H, 4H) -dione with acetic anhydride and with sodium acetate in acetic anhydride proved unsuccessful as did attempts to demonstrate nucleophilic substitution of the quinoxalinedione nucleus by toluene -psulphonyl chloride in the presence of dimethylformamide, aqueous sodium hydroxide, and triethylamine. Evidence for the formation of chloroquinoxalinediones was obtained in the reaction of 1,4- dihydroxyquinoxaline - 2, 3(1H, 4H) -dione with tosyl chloride in dimethylformamide in the presence of triethylamine.The thermal rearrangement of 1- acetoxy -4- methylquinoxaline - 2, 3(1H, 4H) -dione to the 7- acetoxy isomer and the thermally induced ring - contraction of 1- acetoxyquinoxaline -2, 3(1H, 4H)- diones to benzimidazolone derivatives has been demonstrated and mechanisms accounting for these transformations are discussed. The attempted thermal rearrangement of 1, 4- diacetoxyquinoxaline -2, 3(1H, 4H) -di one proved unsuccessful. The thermolytic deoxygenation of 1-hydroxyquinoxaline-2, 3(1H, 4H)-diones to the parent heterocycle in high boiling solvents has been demonstrated. The attempted thermolytic de oxygenation of 1, 4- dihydroxyquinoxaline -2, 3(1H, 4H) -dione proved unsuccessful as did the attempted photolytic de oxygenation of 1- hydroxyquinoxaline -2, 3(1H, 4H)- dione

    Evaluating the suitability of RAS culture environment for rainbow trout and Atlantic salmon: A ten-year progression of applied research and technological advancements to optimize water quality and fish performance

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    Over the last several decades, recirculating aquaculture systems (RAS) have become a viable technology for the production of high-value food-fish. In Norway, for example, many Atlantic salmon smolt farms are now using RAS, and there is increased interest and investment in landbased facilities for the production of larger smolts, post-smolts, and, in some cases, market-size Atlantic salmon. Similar trends are taking shape in other countries, including the United States where multi-million-dollar land-based salmon and trout facilities are being planned and constructed with several already in operation. RAS continuously recycle water through specialized unit processes that recondition the flow to support intensive fish production. Core advantages of RAS include substantial water savings, diminished waste discharge, and increased flexibility for siting facilities near major seafood markets; however, a critical tradeoff is the accumulation of dissolved nutrients, metals, and compounds that can negatively affect fish health and performance in the absence of proper water treatment and system management techniques. Therefore, research that prioritizes assessment of technologies and operational metrics that optimize the RAS environment has been and will continue to be essential for sustainable industry growth. During my 21-year career as a researcher at The Conservation Fund’s Freshwater Institute, I have focused largely on evaluating the suitability of environmental conditions for salmonid production in RAS. Early research sought to identify accumulating water quality variables of concern, followed by studies designed to establish safe water quality thresholds for salmonids, namely nitrate. Assessment of specialized technologies for water quality control was intertwined with these objectives and is now at the forefront of today’s research. As the use of RAS for intensive salmonid production is still a relatively new frontier, novel questions continue to arise and evolve with increasing RAS scale, adoption of new technologies, and the declining availability of clean water resources. My thesis will track the evolution of research that I have contributed to as author and researcher within the focal area of RAS culture environment with special attention to seven peer-reviewed articles. Each manuscript resulted in novel information regarding the RAS environment for salmonids while raising new questions and providing direction for important follow-up studies. This manuscript provides a history of related research, concluding with up-to-date studies that blend optimization of the RAS culture environment with use of advanced water treatment technologies such as ozone and membrane biological reactor systems. My research synopsis will also focus on the relevance and practicality of these studies to the salmonid aquaculture industry, particularly in the United States, and seeks to extract additional value when considering the results with broader perspective related to water use and technology selection for commercial scale operations

    Growth Modelling Components of the AFFFM

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    When developing the AFFFM, a conscious decision was made at an early stage to populate the model with as much data as possible. By doing so it was felt that the model would be more useful to a wider range of users. A module was developed which contains information about potential growth rates, harvest ages and log prices for a number of suitable timber species for the Atherton Tableland, the Darling Downs and the New England Tableland regions of eastern Australia. Data on the potential growth rate, harvest age and product mixtures for tree species suitable for plantations on the New England Tablelands and Darling Downs were generated using the Plantgro program. Users of the model from these areas can choose to load the appropriate values for the various species by specifying the location and soil type of the planned plantation. Data on the potential growth rate, harvest age and timber price for 31 species of cabinet timbers in Far North Queensland were also included. These data were obtained from a previous survey of forestry experts undertaken by Herbohn et al. (1999). This chapter outlines the process through which growth data used in the AFFFM were collected

    Cloning, expression, and localization of a rat brain high-affinity glycine transporter

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    A cDNA clone encoding a glycine transporter has been isolated from rat brain by a combined PCR and plaque-hybridization strategy. mRNA synthesized from this clone (designated GLYT1) directs the expression of sodium-and chloride-dependent, high-affinity uptake of [3H]glycine by Xenopus oocytes. [3H]Glycine transport mediated by clone GLYT1 is blocked by sarcosine but is not blocked by methylaminoisobutyric acid or L-alanine, a substrate specificity similar to that described for a previously identified glycine-uptake system called system Gly. In situ hybridization reveals that GLYT1 is prominently expressed in the cervical spinal cord and brainstem, two regions of the central nervous system where glycine is a putative neurotransmitter. GLYT1 is also strongly expressed in the cerebellum and olfactory bulb and is expressed at lower levels in other brain regions. The open reading frame of the GLYT1 cDNA predicts a protein containing 633 amino acids with a molecular mass of ≈70 kDa. The primary structure and hydropathicity profile of GLYT1 protein reveal that this protein is a member of the sodium- and chloride-dependent superfamily of transporters that utilize neurotransmitters and related substances as substrates
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