81 resultados para Social and spatial dynamics
Resumo:
In this paper we have proposed and analyzed a simple mathematical model consisting of four variables, viz., nutrient concentration, toxin producing phytoplankton (TPP), non-toxic phytoplankton (NTP), and toxin concentration. Limitation in the concentration of the extracellular nutrient has been incorporated as an environmental stress condition for the plankton population, and the liberation of toxic chemicals has been described by a monotonic function of extracellular nutrient. The model is analyzed and simulated to reproduce the experimental findings of Graneli and Johansson [Graneli, E., Johansson, N., 2003. Increase in the production of allelopathic Prymnesium parvum cells grown under N- or P-deficient conditions. Harmful Algae 2, 135–145]. The robustness of the numerical experiments are tested by a formal parameter sensitivity analysis. As the first theoretical model consistent with the experiment of Graneli and Johansson (2003), our results demonstrate that, when nutrient-deficient conditions are favorable for the TPP population to release toxic chemicals, the TPP species control the bloom of other phytoplankton species which are non-toxic. Consistent with the observations made by Graneli and Johansson (2003), our model overcomes the limitation of not incorporating the effect of nutrient-limited toxic production in several other models developed on plankton dynamics.
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Williams Syndrome (WS) is associated with an unusual profile of anxiety, characterised by increased rates of non-social anxiety but not social anxiety (Dodd & Porter, 2009). The present research examines whether this profile of anxiety is associated with an interpretation bias for ambiguous physical, but not social, situations. Sixteen participants with WS, aged 13-34 years, and two groups of typically developing controls matched to the WS group on chronological age (CA) and mental age (MA), participated. Consistent with the profile of anxiety reported in WS, the WS group were significantly more likely to interpret an ambiguous physical situation as threatening than both control groups. However, no between-group differences were found on the ambiguous social situations.
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This paper explores the nature of private social and environmental reporting (SER). From interviews with UK institutional investors, we show that both investors and investees employ Goffmanesque, staged impression management as a means of creating and disseminating a dual myth of social and environmental accountability. The interviewees’ utterances unveil private meetings imbued with theatrical verbal and physical impression management. Most of the time, the investors’ shared awareness of reality belongs to a Goffmanesque frame whereby they accept no intentionality, misrepresentation or fabrication, believing instead that the ‘performers’ (investees) are not intending to deceive them. A shared perception that social and environmental considerations are subordinated to financial issues renders private SER an empty encounter characterised as a relationship-building exercise with seldom any impact on investment decision-making. Investors spoke of occasional instances of fabrication but these were insufficient to break the frame of dual myth creation. They only identified a handful of instances where intentional misrepresentation had been significant enough to alter their reality and behaviour. Only in the most extreme cases of fabrication and lying did the staged meeting break frame and become a genuine occasion of accountability, where investors demanded greater transparency, further meetings and at the extreme, divested shares. We conclude that the frontstage, ritualistic impression management in private SER is inconsistent with backstage activities within financial institutions where private financial reporting is prioritised. The investors appeared to be in a double bind whereby they devoted resources to private SER but were simultaneously aware that these efforts may be at best subordinated, at worst ignored, rendering private SER a predominantly cosmetic, theatrical and empty exercise.
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We have investigated the (001) surface structure of lithium titanate (Li2TiO3) using auger electron spectroscopy (AES), low-energy electron diffraction (LEED), and scanning tunneling microscopy (STM). Li2TiO3 is a potential fusion reactor blanket material. After annealing at 1200 K, LEED demonstrated that the Li2TiO3(001) surface was well ordered and not reconstructed. STM imaging showed that terraces are separated in height by about 0.3 nm suggesting a single termination layer. Moreover, hexagonal patterns with a periodicity of ∼0.4 nm are observed. On the basis of molecular dynamics (MD) simulations, these are interpreted as a dynamic arrangement of Li atoms.
Resumo:
The growing dependence on electricity for economic growth in all countries prompts the need to manage current resources for future sustainability. In today’s world, greater emphasis is placed on energy conservation for energy security and for the development of every economy. However, for some countries understanding the basic drivers to such achievements is farfetched. The research presented in this paper investigates the electricity generation and access potential for Botswana. In addition detailed documentation and 13 years energy consumption and generation trends are investigated. Using questionnaires and empirical studies the energy demand for the entire nation was estimated. From the research it was established that current energy generation trends account for 38- 39% of the country’s population with access to electricity. Considering the percentage rate of sector energy demand, the proposed total installed capacity of 1332 MW, would not meet the country's energy demand at 100% access. The likely consequence of the lack of adequate supply would cumulate to significant increase of imports and/or load shedding to meet demand.
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Radar refractivity retrievals have the potential to accurately capture near-surface humidity fields from the phase change of ground clutter returns. In practice, phase changes are very noisy and the required smoothing will diminish large radial phase change gradients, leading to severe underestimates of large refractivity changes (ΔN). To mitigate this, the mean refractivity change over the field (ΔNfield) must be subtracted prior to smoothing. However, both observations and simulations indicate that highly correlated returns (e.g., when single targets straddle neighboring gates) result in underestimates of ΔNfield when pulse-pair processing is used. This may contribute to reported differences of up to 30 N units between surface observations and retrievals. This effect can be avoided if ΔNfield is estimated using a linear least squares fit to azimuthally averaged phase changes. Nevertheless, subsequent smoothing of the phase changes will still tend to diminish the all-important spatial perturbations in retrieved refractivity relative to ΔNfield; an iterative estimation approach may be required. The uncertainty in the target location within the range gate leads to additional phase noise proportional to ΔN, pulse length, and radar frequency. The use of short pulse lengths is recommended, not only to reduce this noise but to increase both the maximum detectable refractivity change and the number of suitable targets. Retrievals of refractivity fields must allow for large ΔN relative to an earlier reference field. This should be achievable for short pulses at S band, but phase noise due to target motion may prevent this at C band, while at X band even the retrieval of ΔN over shorter periods may at times be impossible.
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A 19 cal ka BP pollen and charcoal record from Lake Shaman (44°S; 71°W, Chile) was analyzed to establish vegetation, fire and climate dynamics of the forest-steppe ecotone in Central Chilean Patagonia. Lake Shaman record indicates that the upper Río Cisnes valley was free of ice at around 19 cal ka BP. From this date and until 14.8 cal ka BP, a grass steppe with high proportions of shrubs associated to colder and drier conditions than present developed in this area. A continuous increase of Nothofagus accompanied by a decline in the steppe shrubs and sudden dominance of paludal over aquatic plants from 11 cal ka BP was associated to effective moisture increase but still under modern values. The replacement of the cold-dry grass-shrub steppe by a similar-than-present forest-steppe ecotone suggests an increase in temperature indicating the onset of the Holocene. At the same time, moderate fire activity suggested by the charcoal record could be related to major fuel availability as consequence of Nothofagus forest expansion. Between 8 and 3 cal ka BP, the record indicates the easternmost position of the forest-steppe ecotone suggesting the highest effective moisture with the establishment of seasonality between 5 and 3 cal ka BP. From 3 cal ka BP, the record indicates a retraction of the forest-steppe ecotone accompanied by a high pollen record variability and an increased fire activity. These late changes suggest decreased effective moisture associated with a high climatic variability. At regional and extra-regional scale, climatic changes at Lake Shaman's record are mostly associated to changes (latitudinal shifts and/or strengthening/weakening) of past Southern Westerlies that were previously recorded along Patagonia from the Lateglacial to the mid-Holocene. During the Late Holocene, a regional pattern characterized by high record variability emerges throughout Central Chilean Patagonia. This variability would be related to (1) low magnitude Southern Westerlies changes probably associated to ENSO and/or SAM or (2) the complex relationships between vegetation, fire and human occupations during the last 3 cal ka.
Resumo:
Research into the dark side of customer management and marketing is progressively growing. The marketing landscape today is dominated with suspicion and distrust as a result of practices that include hidden fees, deception and information mishandling. In such a pessimistic economy, marketers must reconceptualise the notion of fairness in marketing and customer management, so that the progress of sophisticated customisation schemes and advancements in marketing can flourish, avoiding further control and imposed regulation. In this article, emerging research is drawn to suggest that existing quality measures of marketing activities, including service, relationships and experiences may not be comprehensive in measuring the relevant things in the social and ethically oriented marketing landscape, and on that basis does not measure the fairness which truly is important in such an economy. The paper puts forward the concept of Fairness Quality (FAIRQUAL), which includes as well as extends on existing thinking behind relationship building, experience creation and other types of customer management practices that are believed to predict consumer intentions. It is proposed that a fairness quality measure will aid marketers in this challenging landscape and economy.
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This paper seeks to chronicle the roots of corporate governance form its narrow shareholder perspective to the current bourgeoning stakeholder approach while giving cognizance to institutional investors and their effective role in ESG in light of the King Report III of South Africa. It is aimed at a critical review of the extant literature from the shareholder Cadbury epoch to the present day King Report novelty. We aim to: (i) offer an analytical state of corporate governance in the Anglo-Saxon world, Middle East and North Africa (MENA), Far East Asia and Africa; and (ii) illuminate the lead role the king Report of South Africa is playing as the bellwether of the stakeholder approach to corporate governance as well as guiding the role of institutional investors in ESG.
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It is widely acknowledged that innovation is one of the pillars of multinational enterprises (MNEs) and that technological knowledge from different host locations is a key factor to the MNEs’ competitive advantages development. Concerning these assumptions, in this paper we aim to understand how the social and the relational contexts affect the conventional and reverse transfer of innovation from MNEs’ subsidiaries hosted in emerging markets. We analyzed the social context through the institutional profile (CIP) level and the relational context through trust and integration levels utilizing a survey sent to 172 foreign subsidiaries located in Brazil, as well as secondary data. Through an ordinary least squares regression (OLS) analysis we found that the relational context affects the conventional and reverse innovation transfer in subsidiaries hosted in emerging markets. We however did not find support for the social context effect.
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Ground-based observations of dayside auroral forms and magnetic perturbations in the arctic sectors of Svalbard and Greenland, in combination with the high-resolution measurements of ionospheric ion drift and temperature by the EISCAT radar, are used to study temporal/spatial structures of cusp-type auroral forms in relation to convection. Large-scale patterns of equivalent convection in the dayside polar ionosphere are derived from the magnetic observations in Greenland and Svalbard. This information is used to estimate the ionospheric convection pattern in the vicinity of the cusp/cleft aurora. The reported observations, covering the period 0700-1130 UT, on January 11, 1993, are separated into four intervals according to the observed characteristics of the aurora and ionospheric convection. The morphology and intensity of the aurora are very different in quiet and disturbed intervals. A latitudinally narrow zone of intense and dynamical 630.0 nm emission equatorward of 75 degrees MLAT, was observed during periods of enhanced antisunward convection in the cusp region. This (type 1 cusp aurora) is considered to be the signature of plasma entry via magnetopause reconnection at low magnetopause latitudes, i.e. the low-latitude boundary layer (LLB I,). Another zone of weak 630.0 nm emission (type 2 cusp aurora) was observed to extend up to high latitudes (similar to 79 degrees MLAT) during relatively quiet magnetic conditions, when indications of reverse (sunward) convection was observed in the dayside polar cap. This is postulated to be a signature of merging between a northward directed IMF (B-z > 0) and the geomagnetic field poleward of the cusp. The coexistence of type 1 and 2 auroras was observed under intermediate circumstances. The optical observations from Svalbard and Greenland were also used to determine the temporal and spatial evolution of type 1 auroral forms, i.e. poleward-moving auroral events occurring in the vicinity of a rotational convection reversal in the early post-noon sector. Each event appeared as a local brightening at the equatorward boundary of the pre-existing type 1 cusp aurora, followed by poleward and eastward expansions of luminosity. The auroral events were associated with poleward-moving surges of enhanced ionospheric convection and F-layer ion temperature as observed by the EISCAT radar in Tromso. The EISCAT ion flow data in combination with the auroral observations show strong evidence for plasma flow across the open/closed field line boundary.
Resumo:
1. Agri-environment schemes remain a controversial approach to reversing biodiversity losses, partly because the drivers of variation in outcomes are poorly understood. In particular, there is a lack of studies that consider both social and ecological factors. 2. We analysed variation across 48 farms in the quality and biodiversity outcomes of agri-environmental habitats designed to provide pollen and nectar for bumblebees and butterflies or winter seed for birds. We used interviews and ecological surveys to gather data on farmer experience and understanding of agri-environment schemes, and local and landscape environmental factors. 3. Multimodel inference indicated social factors had a strong impact on outcomes and that farmer experiential learning was a key process. The quality of the created habitat was affected positively by the farmer’s previous experience in environmental management. The farmer’s confidence in their ability to carry out the required management was negatively related to the provision of floral resources. Farmers with more wildlife-friendly motivations tended to produce more floral resources, but fewer seed resources. 4. Bird, bumblebee and butterfly biodiversity responses were strongly affected by the quantity of seed or floral resources. Shelter enhanced biodiversity directly, increased floral resources and decreased seed yield. Seasonal weather patterns had large effects on both measures. Surprisingly, larger species pools and amounts of semi-natural habitat in the surrounding landscape had negative effects on biodiversity, which may indicate use by fauna of alternative foraging resources. 5. Synthesis and application. This is the first study to show a direct role of farmer social variables on the success of agri-environment schemes in supporting farmland biodiversity. It suggests that farmers are not simply implementing agri-environment options, but are learning and improving outcomes by doing so. Better engagement with farmers and working with farmers who have a history of environmental management may therefore enhance success. The importance of a number of environmental factors may explain why agri-environment outcomes are variable, and suggests some – such as the weather – cannot be controlled. Others, such as shelter, could be incorporated into agri-environment prescriptions. The role of landscape factors remains complex and currently eludes simple conclusions about large-scale targeting of schemes.