1,853,552 research outputs found

    Elemental Abundance Analysis of Single and Binary Late-B Stars Using Sub-meter Class Telescopes: HR 342, HR 769, HR 1284, and HR 8705

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    We test the capabilities of 0.4 m telescopes equipped with an \'{e}chelle spectrograph to derive fundamental parameters and elemental abundances of four late-B type stars: HR 342, HR 769, HR 1284, and HR 8705. The medium resolution (R~14000) spectra covering the wavelength range of 4380-7350 {\AA} of the four stars have been obtained using the 40-cm-telescope in Ankara University Kreiken Observatory (AUKR). Using spectrum synthesis, we were able to derive the abundances of eleven chemical elements. We find that these stars do not show remarkable departures from the solar abundances, except for HR 8705 and the primary component of HR 1284, which exhibit slight underabundances of a few elements, i.e., O, Mg, Al, Si, and Fe. We also find that HR 1284 is probably a new spectroscopic binary star. In order to model the spectrum of this object, one of us (TK) has developed a new graphic interface which allows us to synthesize the composite spectrum of binary stars.Comment: 3 pages, 2 figures and 1 table. Accepted proceeding of the Observing techniques, instrumentation and science for metre-class telescopes II conference, September 24-28, 2018, Tatransk\'a Lomnica, Slovaki

    Conservation of Arabidopsis thaliana photoperiodic flowering time genes in onion (Allium cepa L.)

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    The genetics underlying onion development is poorly understood. Here the characterisation of onion homologues of Arabidopsis photoperiodic flowering pathway genes is reported with the end goal of accelerating onion breeding programmes by understanding the genetic basis of adaptation to different latitudes. The expression of onion GI, FKF1 and ZTL homologues under SD and LD conditions was examined using quantitative RT-PCR. The expression of AcGI and AcFKF1 was examined in onion varieties which exhibit different daylength responses. Phylogenetic trees were constructed to confirm the identity of the homologues. AcGI and AcFKF1 showed diurnal expression patterns similar to their Arabidopsis counterparts while AcZTL was found to be constitutively expressed. AcGI showed similar expression patterns in varieties which exhibit different daylength responses whereas AcFKF1 showed differences. It is proposed that these differences could contribute to the different daylength responses in these varieties. Phylogenetic analyses showed that all the genes isolated are very closely related to their proposed homologues. The results presented here show that key genes controlling photoperiodic flowering in Arabidopsis are conserved in onion and a role for these genes in the photoperiodic control of bulb initiation is predicted. This theory is supported by expression and phylogenetic data

    Improved efficiency of nutrient and water use for high quality field vegetable production using fertigation

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    Drip-based fertigation may improve the application efficiency of water and nutrients while maintaining or improving marketable yield and quality at harvest and post-harvest. Two plantings of lettuce (Lactuca sativa) were grown in the UK, with six N treatments and two methods of irrigation and N application. The conventional overhead irrigated treatments had all N applied in the base dressing with irrigation scheduled from SMD calculations. The closed loop treatments had nitrogen and irrigation delivered via drip automatically controlled by a sensor and logger system. The work established that water content in the root zone can be monitored in real time using horizontally oriented soil moisture sensors linked to data logging and telemetry, and that these data can be used to automatically trigger drip irrigation for commercially grown field vegetables. When the closed loop irrigation control was combined with fertigation treatments, lettuce crops were grown with savings of up to 60% and 75% of water and nitrogen respectively, compared to standard UK production systems. However, excess supply of N through fertigation rather than solid fertiliser was more detrimental to marketable yield and post harvest quality highlighting that care is needed when selecting N rates for fertigation

    Combatting Skepticism Towards HR

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    [Excerpt] When assessing the essentiality of HR within a firm, one must first ask what is meant by the word “essential” within a business context. The trickiness here, however, is that such a definition is highly contingent on the type and size of a particular firm. If one defines “essential” as “indispensable,” then HR is almost certainly not essential in very small firms. In such instances, the work of HR can be done by other managers and the owners themselves. On the other hand, if one defines “essential” as “adding considerable value,” then innovative human resource policies can create a competitive advantage even in the smallest of firms. Instead of relying on a single definition of essentiality, this essay will focus on the reasons why human resources practices are often called into question in the first place. Furthermore, I will propose recommendations on how to combat skepticism toward HR

    Why carbon footprinting (and carbon labelling) only tells half the story

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    The UK is a world leader in the use of carbon footprints. The introduction of PAS2050 has legitimised carbon footprinting and manufacturers and retailers have responded by estimating carbon footprints for selected products. In industrial production, where the relationship between inputs and outputs is constant and the process is tightly controlled, carbon footprints tend to be reproducible. However, agricultural production is different, being influenced by biological, geological and climatic variation. Thus, although the use of a single value to represent the carbon burden of a food product is appealing, in practice it can be misleading. This paper discusses the variability associated with carbon footprints of agricultural products and considers the value of carbon labelling. We suggest that carbon footprinting is a useful approach that will assist in the transition to a low carbon society but that current approaches to carbon labelling may not help consumers understand the carbon burden of agricultural products

    Assessing the costs and benefits of agricultural production using an ecosystem approach

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    Integrated Farm Management (IFM) is seen as one way for agriculture to contribute towards the UKs challenging national targets for climate change, pollution, biodiversity and other environmental factors. Whilst it is clear that IFM and associated assurance schemes have a role in food quality and enhancement of the environment, they fail to address a number of issues. In particular, they fail to take sufficient account of ‘impact’ and ‘outcome’. In contrast, the relatively new concept of an ecosystem approach does consider these and there is extensive synergy between this approach and IFM. This is pertinent because the UK Department for the Environment, Food and Rural Affairs (Defra) is taking steps to embed an ecosystem approach in policy-making and delivery. This paper sets out to explore the links between IFM and an ecosystem approach and introduces a simple matrix to show how an ecosystem approach might be used to assess the outcome of IFM practices. Limited use of an ecosystem approach suggests that this type of methodology could deliver useful results for IFM. However, it should be used as a decision-support tool rather than a decision-maker. The advantage of using an ecosystem approach for assessing the impact of IFM is that it provides a holistic assessment of land management strategies, rather than focusing on either cropping, or environmental management, alone. However, the values assigned to individual parameters are generally based on expert opinion and, as such, are open to interpretation. Indeed, an ecosystem approach should be interdisciplinary, utilising the knowledge and expertise of a range of stakeholders. Whilst the development of an ecosystem approach for use within an agricultural setting shows promise, it is still in its infancy. There is a need for much discussion, between many disciplines, before it becomes accepted practice

    Co-incorporation of biodegradable wastes with crop residues to reduce nitrate pollution of groundwater and decrease waste disposal to landfill

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    Return of high nitrogen (N) content crop residues to soil, particularly in autumn, can result in environmental pollution resulting from gaseous and leaching losses of N. The EU Landfill Directive will require significant reductions in the amounts of biodegradable materials going to landfill. A field experiment was set up to examine the potential of using biodegradable waste materials to manipulate losses of N from high N crop residues in the soil. Leafy residues of sugar beet were co-incorporated into soil with materials of varying C:N ratios, including molasses, compactor waste, paper waste, green waste compost and cereal straw. The amendment materials were each incorporated to provide approximately 3.7 t C per hectare. The most effective material for reducing nitrous oxide (N2O) production and leaching loss of NO3− was compactor waste, which is the final product from the recycling of cardboard. Adding molasses increased N2O and NO3− leaching losses. Six months following incorporation of residues, the double rate application of compactor waste decreased soil mineral N by 36 kg N per hectare, and the molasses increased soil mineral N by 47 kg N per hectare. Compactor waste reduced spring barley grain yield by 73% in the first of years following incorporation, with smaller losses at the second harvest. At the first harvest, molasses and paper waste increased yields of spring barley by 20 and 10% compared with sugar beet residues alone, and the enhanced yield persisted to the second harvest. The amounts of soil mineral N in the spring and subsequent yields of a first cereal crop were significantly correlated to the lignin and cellulose contents of the amendment materials. Yield was reduced by 0.3–0.4 t/ha for every 100 mg/g increase in cellulose or lignin content. In a second year, cereal yield was still reduced and related to the cellulose content of the amendment materials but with one quarter of the effect. Additional fertilizer applied to this second crop did not relieve this effect. Although amendment materials were promising as tools to reduce N losses, further work is needed to reduce the negative effects on subsequent crops which was not removed by applying 60 kg/ha of fertilizer N

    HR: Innovation\u27s Accelerator

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    [Excerpt] Amazon and Borders. Netflix and Blockbuster. Uber and taxi drivers. Digital camera makers and Kodak. The list could go on and on. Individual stories of disruptive innovation such as these are some of the most well known - and ca utionary - business tales of our times. Yet, many firms remain blindly confident that such an outcome will never happen to their company. Recent research suggests otherwise. According to a 2016 report by the innova tion -focused firm Innosight, high M&A activity and billion -dollar startup valuations are creating significant market turbulence, with 28 companies being replaced on the S&P 500 index in 2015 alone. At current churn rates, Innosight estimates that by 2026, half of the entire S&P 500 will be replaced-a staggering and sobering figure. As such, the ability to develop deep innovation capabilities has never been more important, for both growth and survival. This year\u27s CAHRs Research Assistant (RA) project takes on this very topic, examining the intersection between HR & Innovation, and how progressive HR leaders can create value and impact through a range of human capital strategies and solutions. Consistent with past CAHRS RA projects, the research methodology for this paper was qualitative in nature, including 41 interviews with HR and business executives at 31 different partner companies, all within the Fortune 500. Unique to this year\u27s project, and in addition to the traditional focus on HR leaders, research assistants also spoke with more than 10 business and innovation leaders, to get a richer, deeper view of innovation. Interviews consisted of 11 questions, but largely focused on three key categories: Why is innovation often so hard? What factors lead to innovation success? How can HR leaders be innovation change agents within their company? Our findings and recommendations follow below

    Why have HR Standards?

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    Domestication as innovation : the entanglement of techniques, technology and chance in the domestication of cereal crops

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    The origins of agriculture involved pathways of domestication in which human behaviours and plant genetic adaptations were entangled. These changes resulted in consequences that were unintended at the start of the process. This paper highlights some of the key innovations in human behaviours, such as soil preparation, harvesting and threshing, and how these were coupled with genetic ‘innovations’ within plant populations. We identify a number of ‘traps’ for early cultivators, including the needs for extra labour expenditure on crop-processing and soil fertility maintenance, but also linked gains in terms of potential crop yields. Compilations of quantitative data across a few different crops for the traits of nonshattering and seed size are discussed in terms of the apparently slow process of domestication, and parallels and differences between different regional pathways are identified. We highlight the need to bridge the gap between a Neolithic archaeobotanical focus on domestication and a focus of later periods on crop-processing activities and labour organization. In addition, archaeobotanical data provide a basis for rethinking previous assumptions about how plant genetic data should be related to the origins of agriculture and we contrast two alternative hypotheses: gradual evolution with low selection pressure versus metastable equilibrium that prolonged the persistence of ‘semi-domesticated’ populations. Our revised understanding of the innovations involved in plant domestication highlight the need for new approaches to collecting, modelling and integrating genetic data and archaeobotanical evidence