884 resultados para Seedling emergence


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Supply chain formation (SCF) is the process of determining the set of participants and exchange relationships within a network with the goal of setting up a supply chain that meets some predefined social objective. Many proposed solutions for the SCF problem rely on centralized computation, which presents a single point of failure and can also lead to problems with scalability. Decentralized techniques that aid supply chain emergence offer a more robust and scalable approach by allowing participants to deliberate between themselves about the structure of the optimal supply chain. Current decentralized supply chain emergence mechanisms are only able to deal with simplistic scenarios in which goods are produced and traded in single units only and without taking into account production capacities or input-output ratios other than 1:1. In this paper, we demonstrate the performance of a graphical inference technique, max-sum loopy belief propagation (LBP), in a complex multiunit unit supply chain emergence scenario which models additional constraints such as production capacities and input-to-output ratios. We also provide results demonstrating the performance of LBP in dynamic environments, where the properties and composition of participants are altered as the algorithm is running. Our results suggest that max-sum LBP produces consistently strong solutions on a variety of network structures in a multiunit problem scenario, and that performance tends not to be affected by on-the-fly changes to the properties or composition of participants.

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This paper examines the effects of New Public Management reforms on the information infrastructure underpinning the work of public service professionals. Focussing on the case of the British National Health Service (NHS), the paper argues that hospital accounting reforms played a significant role in the emergence of standardised models of clinical practice. The paper moreover argues that, under the label “care pathways”, such standardised models of clinical practice became embedded in the information infrastructure of the NHS and concludes by discussing their implications for the work of doctors and hospital accountants.

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This paper introduces a quantitative method for identifying newly emerging word forms in large time-stamped corpora of natural language and then describes an analysis of lexical emergence in American social media using this method based on a multi-billion word corpus of Tweets collected between October 2013 and November 2014. In total 29 emerging word forms, which represent various semantic classes, grammatical parts-of speech, and word formations processes, were identified through this analysis. These 29 forms are then examined from various perspectives in order to begin to better understand the process of lexical emergence.

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This article considers how the field of voluntary sector studies (VSS) in the UK emerged. Drawing on published and unpublished documents as well as on semi-structured interviews with people involved in the early development of VSS, a timeline of key events is suggested. The analysis reveals both social and cognitive elements in the field's development and considers the broader policy and institutional context within which key events of the VSS field occurred.

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Iridescent blue leaf coloration in four Malaysian rain forest understory plants, Diplazium tomentosum Bl. (Athyriaceae), Lindsaea lucida Bi. (Lindsaeaceae), Begonia pavonina Ridl. (Begoniaceae), and Phyllagathis rotundifolia Bl. (Melastoma- taceae) is caused by a physical effect, constructive interference of reflected blue light. The ultrastructural basis for this in D. tomentosum and L. lucida is multiple layers of cellulose microfibrils in the uppermost cell walls of the adaxial epidermis. The helicoidal arrangement of these fibrils is analogous to that which produces a similar color in arthropods. In B. pavonina and P. rotundifolia the blue-green coloration is caused by parallel lamellae in specialized plastids adjacent to the abaxial wall of the adaxial epidermis. The selective advantage of this color production, if any, is unknown.

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Seedlings of the red mangrove, Rhizophora mangle L., were grown under light conditions differing in both photosynthetic photon flux density (PPFD) and spectral quality (red:far-red ratio, R:FR). During the first 8 mo of development, parameters of stem, leaf, and root growth were affected by PPFD. Significant responses to lowered R:FR, however, were limited to internode extension. The results are moderately indicative of a strategy to persist in shade, but illustrate the complexity of light responses and suggest that precise categorization as shade-tolerant or -intolerant may be unbefitting for this species at this particular stage of development.

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This work chronicles how queer individuals politicized their same-sex desires from the post-World War II era to the mid-1990s. Using Miami as a site of exploration, this work demonstrates the shift from understanding homosexuality as a same-sex "desire" to a distinct form of "civil rights." It argues that by no means was it inevitable that queer issues entered the American political mainstream. This project pays particular attention to Miami's Cuban exile community, as it managed to garner great socio-political power in the city. Like others in the city's power structure, Miami's Cuban exiles were also fundamentally traditionalists. Together, these phenomena crystallized into a matrix of obstacles that stunted the growth of the gay rights movement. This work demonstrates the historical dynamics of sexuality and politics by contextualizing immigration, ethnicity, race, consumerism, and Cold War domestic and foreign policy.

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The current study assessed the importance of infant detection of contingency and head and eye gaze direction in the emergence of social referencing. Five- to six-month-old infants' detection of affect-object relations and subsequent manual preferences for objects paired with positive expressions were assessed. In particular, the role of contingency between toys' movements and an actress's emotional expressions as well as the role of gaze direction toward the toys' location were examined. Infants were habituated to alternating films of two toys each paired with an actress's affective expression (happy and fearful) under contingent or noncontingent and gaze congruent or gaze incongruent conditions. Results indicated that gaze congruence and contingency between toys' movements and a person's affective expressions were important for infant perception of affect-object relations. Furthermore, infant perception of the relation between affective expressions and toys translated to their manual preferences for the 3-dimensional toys. Infants who received contingent affective responses to the movements of the toys spent more time touching the toy that was previously paired with the positive expression. These findings demonstrate the role of contingency and gaze direction in the emergence of social referencing in the first half year of life.^

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This study examines some concerns that derive from Suriname‘s May-July 2010 elections, which resulted in the re-emergence of erstwhile military ruler and convicted drug trafficker, Désiré (Desi) Bouterse, as President of the Republic. The victory reflects Bouterse‘s political acumen in aggregating disparate political interests and in establishing a viable coalition government. But because of his history and profile, this triumph has generated anxiety in some places internationally. In this respect, the study examines anxieties related to three matters: (a) relations with Guyana, where there is an existing territorial dispute and a recently resolved maritime dispute, (b) illegal drug trafficking operations, and (c) foreign policy engagement with Venezuela. There has been a flurry of bilateral activities—including several presidential summits—with Guyana since President Bouterse‘s inauguration, albeit seemingly more about symbolism than substance. Although the maritime dispute was settled by a Tribunal of the United Nations Convention of the Law of the Sea in 2007, the 15,000 km2 New River Triangle is still unresolved. Indeed, in June 2011 President Bouterse reasserted Suriname‘s claim to the Triangle. Suriname has upped the ante in that dispute by portraying internationally the map of Suriname as inclusive of the disputed area. In all likelihood that self-redefinition slowly will become the country‘s cartographic definition in the eyes of the world if Guyana does not successfully rebuff that move or pursue the definitive settlement of the dispute. A geonarcotics assessment shows Suriname to be still heavily implicated in trafficking, because of geography, law enforcement limitations, corruption, and other factors. But despite Bouterse‘s drug-related history and that of former senior military officers, several reasons suggest the inexpediency of a narco-state being created by Bouterse. As well, as part of Suriname‘s pursuit of increased Caribbean and South American engagement, it has boosted relations with Venezuela, which has included it in PetroCaribe and provided housing and agricultural aid. However, the engagement appears to be driven more by pragmatism and less by any ideological affinity with Hugo Chavez.

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Siloxanes are widely used in personal care and industrial products due to their low surface tension, thermal stability, antimicrobial and hydrophobic properties, among other characteristics. Volatile methyl siloxanes (VMS) have been detected both in landfill gas and biogas from anaerobic digesters at wastewater treatment plants. As a result, they are released to gas phase during waste decomposition and wastewater treatment. During transformation processes of digester or landfill gas to energy, siloxanes are converted to silicon oxides, leaving abrasive deposits on engine components. These deposits cause increased maintenance costs and in some cases complete engine overhauls become necessary. The objectives of this study were to compare the VMS types and levels present in biogas generated in the anaerobic digesters and landfills and evaluate the energetics of siloxane transformations under anaerobic conditions. Siloxane emissions, resulting from disposal of silicone-based materials, are expected to increase by 29% within the next 10 years. Estimated concentrations and the risk factors of exposure to siloxanes were evaluated based on the initial concentrations, partitioning characteristics and persistence. It was determined that D4 has the highest risk factor associated to bioaccumulation in liquid and solid phase, whereas D5 was highest in gas phase. Additionally, as siloxanes are combusted, the particle size range causes them to be potentially hazardous to human health. When inhaled, they may affix onto the alveoli of the lungs and may lead to development of silicosis. Siloxane-based COD-loading was evaluated and determined to be an insignificant factor concerning COD limits in wastewater. Removal of siloxane compounds is recommended prior to land application of biosolids or combustion of biogas. A comparison of estimated costs was made between maintenance practices for removal of siloxane deposits and installation/operation of fixed-bed carbon absorption systems. In the majority of cases, the installation of fixed-bed adsorption systems would not be a feasible option for the sole purpose of siloxane removal. However they may be utilized to remove additional compounds simultaneously.

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In 1998, a dispute between a federal government agency and the local community of Chacchoben resulted in the emergence of a community-based ecotourism (CBE) enterprise to be fully owned and operated by the community in conjunction with a complex arrangement of agreements and partnerships with external actors. CBE is usually framed as a lower-impact, often small-scale alternative to mass tourism and as a conservation and development strategy that can hypothetically protect biologically diverse landscapes while improving the lives of marginalized peasant and indigenous communities through their participation. This case study analyzes the roles of common property land tenure and social capital and how the unique dilemma of a mass community-based ecotourism theme park emerged in Chacchoben. Findings indicate that local decisions and processes of development, conservation, and land use are affected by the complex interaction between local and external institutions and fluctuating levels of social capital.

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We analyze a recent proposal for spontaneous mirror symmetry breaking based on the coupling of first-order enantioselective autocatalysis and direct production of the enantiomers that invokes a critical role for intrinsic reaction noise. For isolated systems, the racemic state is the unique stable outcome for both stochastic and deterministic dynamics when the system is in compliance with the constraints dictated by the thermodynamics of chemical reaction processes. In open systems, the racemic outcome also results for both stochastic and deterministic dynamics when driving the auto-catalysis unidirectionally by external reagents. Nonracemic states can result in the latter only if the reverse reactions are strictly zero: these are kinetically controlled outcomes for small populations and volumes, and can be simulated by stochastic dynamics. However, the stability of the thermodynamic limit proves that the racemic outcome is the unique stable state for strictly irreversible externally driven autocatalysis. These findings contradict the suggestion that the inhibition requirement of the Frank autocatalytic model for the emergence of homochirality may be relaxed in a noise-induced mechanism.

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Purpose - This paper aims to provide evidence to suggest that private social and environmental reporting (i.e. one-on-one meetings between institutional investors and investees on social and environmental issues) is beginning to merge with private financial reporting and that, as a result, integrated private reporting is emerging. Design/methodology/approach - In this paper, 19 FTSE100 companies and 20 UK institutional investors were interviewed to discover trends in private integrated reporting and to gauge whether private reporting is genuinely becoming integrated. The emergence of integrated private reporting through the lens of institutional logics was interpreted. The emergence of integrated private reporting as a merging of two hitherto separate and possibly rival institutional logics was framed. Findings - It was found that specialist socially responsible investment managers are starting to attend private financial reporting meetings, while mainstream fund managers are starting to attend private meetings on environmental, social and governance (ESG) issues. Further, senior company directors are becoming increasingly conversant with ESG issues. Research limitations/implications - The findings were interpreted as two possible scenarios: there is a genuine hybridisation occurring in the UK institutional investment such that integrated private reporting is emerging or the financial logic is absorbing and effectively neutralising the responsible investment logic. Practical implications - These findings provide evidence of emergent integrated private reporting which are useful to both the corporate and institutional investment communities as they plan their engagement meetings. Originality/value - No study has hitherto examined private social and environmental reporting through interview research from the perspective of emergent integrated private reporting. This is the first paper to discuss integrated reporting in the private reporting context.