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In this chapter, a novel framework is proposed to address critical mobility management challenges, including frequent handovers (HOs), handover failure (HOF), and excessive energy consumption for seamless HO in emerging dense wireless cellular networks. In particular, we develop a model that exploits broadband mmW connectivity whenever available to cache content that MUEs are interested in. Thus it will enable the MUEs to use the cached content and avoid unnecessary HO to small cell base stations (SCBSs) with relatively small cell sizes. First, we develop a geometric model to derive tractable, closed-form expressions for key performance metrics, such as the probability of caching, cumulative distribution function of caching duration, and the average data rate for content caching over an mmW link. In addition, we provide insight on the performance gains that caching in mmW–mW networks can yield in terms of reducing the number of HOs and the average HOF.
Chapter 5 frames the book’s narrative in the style of a lengthy coda. It is concerned with how the bark’s prevalence, wide fame and general ‘usefulness’ in therapeutic practice among geographically disperse and socially diverse societies affected its natural habitat in the central and northern Andes. The bark’s very ‘mobility’ and the popular demand that arose for it, the chapter argues, altered the harvest areas’ landscape of possession, commerce and demographics, the distribution and abundance of vegetation, and the livelihood, health and fate of the men and women implicated in harvesting, processing and conveying the bark. The chapter reminds readers, at parting, how plant trade, therapeutic exchange and epistemic brokerage are not extricable from time and space. Consumption and the imaginaries, therapeutic practice and medical understandings attendant to it invariably begins with changes to the material world, to physical nature and society.
The aim of this paper is to study the role of the distribution of income by age group on the existence of speculative bubbles. A crucial question is whether this distribution may promote a bubble associated to a larger level of capital, that is a productive bubble. We address these issues in an overlapping generations model where agents live three periods and productive investment done in the first period of life is an illiquid investment whose return occurs in the following two periods. A bubble is a liquid speculative investment that facilitates intertemporal consumption smoothing. We show that the distribution of income by age group determines both the existence and the effect of bubbles on aggregate production. We also show that fiscal policy, by changing the distribution of income, may facilitate or prevent the existence of bubbles and may also modify the effect that bubbles have on aggregate production.
The last decade has seen the development of a range of new statistical and computational techniques for analysing large collections of radiocarbon (14C) dates, often but not exclusively to make inferences about human population change in the past. Here we introduce rcarbon, an open-source software package for the R statistical computing language which implements many of these techniques and looks to foster transparent future study of their strengths and weaknesses. In this paper, we review the key assumptions, limitations and potentials behind statistical analyses of summed probability distribution of 14C dates, including Monte-Carlo simulation-based tests, permutation tests, and spatial analyses. Supplementary material provides a fully reproducible analysis with further details not covered in the main paper.
A widespread response to the pressures placed on the ecological condition of rivers is the design and implementation of environmental flow regimes in domestic regulatory frameworks for water. Environmental interests in water are not confined to hydrological functioning but include relationships between water resources and human cultural and economic livelihoods, including those of Indigenous communities. Since the mid-1980s there has been some provision for environmental flows in Chilean law. However, the legal and policy requirements are limited in scope and have been poorly implemented by regulatory institutions. In this article we critically examine the treatment of environmental flows in Chilean legal and policy frameworks. We argue that there is an urgent need for a comprehensive minimum flow regime in Chile to protect the environmental qualities of rivers, which must also reflect and provide for Indigenous water rights and interests. The developing constitutional crisis in Chile, the most significant political crisis since the end of the Pinochet dictatorship (1973–90), highlights the need to revisit the sensitive and unresolved issues of water governance and equity.
The analysis of the geographical distribution of hospital cases is obviously important for the purpose of planning hospital services, but it is of even greater significance in the planning of psychiatric services. This concern motivated our seven-year-long study, which examined hospitalization risks among various categories of psychiatric disorders in the major German city of Hamburg. Our database encompassed 77% (n = 64,000) of all psychiatric admissions in a total of 41 hospitals, most of which are general hospitals. In order to carry out the geographical analysis we employed a new statistical method based on a mixture distribution model. According to our findings, the strongest indications of an increased frequency were among male cases of schizophrenia, drug abuse and organic psychoses, and female cases of neurotic disorders, personality disorders, drug abuse and schizophrenia. We found that some areas are exposed to a risk of hospitalization for these diagnostic categories which is more than 50% above the reference. Contrary to other authors we did not identify an increased frequency of admission concentrated in the inner-city area for any of the diagnostic groups. The risk of hospitalization for schizophrenics was almost entirely associated with the close proximity of psychiatric units, while the risks for neuroses and personality disorders, as well as alcohol and drug abuse, appeared to be concentrated in areas of low social status. However, a statistically relevant correlation between an increased risk of hospitalization and low social status could be determined only for drug abuse and alcoholism. In the end, we did identify two areas in which there was an increased risk of hospitalization for several diagnostic groups, and this information will undoubtedly facilitate the planning of hospital and psychiatric services. The fact that our findings deviate to some extent from other authors – especially with respect to neuroses and personality disorders, but also to addiction – can be attributed to the inclusion of psychiatric cases from general hospitals in our geographic analysis.
Brazil has a high diversity of primates, but increasing anthropogenic pressures and climate change could influence forest cover in the country and cause future changes in the distribution of primate populations. Here we aim to assess the long-term suitability of habitats for the conservation of three threatened Brazilian primates (Alouatta belzebul, Sapajus flavius and Sapajus libidinosus) through (1) estimating their current and future distributions using species distribution models, (2) evaluating how much of the areas projected to be suitable is represented within protected areas and priority areas for biodiversity conservation, and (3) assessing the extent of remaining forest cover in areas predicted to be suitable for these species. We found that 88% of the suitable areas are outside protected areas and only 24% are located in areas with forest cover. Although not within protected areas, 27% of the climatically suitable areas are considered priority areas for conservation. Future projections, considering a severe climate change scenario, indicate that A. belzebul, S. flavius and S. libidinosus may lose up to 94, 98 and 54% of their suitable range, respectively. The establishment of primate populations and their long-term survival in these areas are at risk. Mitigation actions such as the implementation of new protected areas, forest restoration and reduction of greenhouse gas emissions will be essential for the conservation of Brazilian primates.
Some negotiators (such as US President Donald Trump) think of negotiation as a zero-sum game, others (such as German Chancellor Angela Merkel) as an opportunity for win–win. In reality, most transactions include both aspects. Paradoxically, negotiations require the creation as well as the distribution of value. While they can be compatible, often they are not. I show the six tactics that are required for each, thus arriving at the tactical paradox of the task. It is graphically illustrated by the symbol of Yin & Yang.
We investigated the seasonal occurrence and vertical distribution/migration of larval and juvenile northern smoothtongue, Leuroglossus schmidti (Pisces, Bathylagidae), in oceanic areas of the western subarctic Pacific. This species was the most abundant larval fish and one of the most abundant juvenile/adult fish at the study site. Larval recruitment of this species occurred in early March to mid-October. Larvae were found, however, throughout all seasons, suggesting that some had overwintered. The highest abundance (5.8 individuals m–2) of larvae was in summer. During summer and autumn, hatching mainly occurred at 100–150-m depth and larvae migrated toward the surface with growth. Once larvae reached about 20 mm in length, they moved below 100 m, and larger larvae (over 24 mm) exhibited diel vertical migration. The abundance of juveniles integrated through the water column was relatively constant (0.3 individuals m–2) throughout the study period. They were collected from below 300 m during the day, and part of the population (13–38%) swam into the epipelagic layer at night. The information on early stages of L. schmidti presented here provides a basis for future investigations of mesopelagic fish ecology in oceanic areas of the western subarctic North Pacific Ocean.
Equity and efficiency are crucial issues behind any tax reform, but they are particularly relevant in countries with high inequality and large shares of poverty. This paper provides a comprehensive socio-economic empirical assessment of Mexico's proposed (and partially implemented) tax reforms in the energy domain, and of a hypothetical partial removal of existing electricity subsidies. Using a rich household income and expenditure survey within the context of a demand system adjustment of non-durable goods, the article provides the public-revenue, environmental and distributional impacts from the simulation of different combinations of energy taxation, subsidy-removal and distributive offsets. The paper also provides detailed ex-ante evidence on the effects of compensatory devices that may contribute to the successful implementation of energy reform packages and significant poverty alleviation in Mexico.
For much of the twentieth century, Indigenous writers faced daunting barriers in getting their books published; indeed, lack of access, delays in publishing, inadequate distribution, institutional racism, and precarious archiving practices have shaped the history of Indigenous writing in Canada. The obstacles to publishing reflect a larger reality in which the forces of appropriation continue to attempt to dispossess Indigenous people of lands, languages, communities, and families. Particularly since the 1990s, Indigenous writers have used strategies of reframing and de-framing in order to bring stories that have been overlooked back into circulation, and to tell new stories outside of the ever-adapting box of what is expected as “Indigenous literature.” Writers shift the frame to make stories more legible—or in some cases, to deliberately foreground silence and what is not (yet) told. This struggle to re-frame, de-frame, and shatter the existing frames of stories have opened up new spaces of freedom in Indigenous literary expression.
In this paper, we consider finite mixture models with components having distributions from the location-scale family. We then discuss the usual stochastic order and the reversed hazard rate order of such finite mixture models under some majorization conditions on location, scale and mixing probabilities as model parameters.
Invasive species are widely recognized as a major threat to global diversity and an important factor associated with global change. Species distribution models (SDMs) have been widely applied to determine the range that invasive species could potentially occupy, but most examples focus on predictive variables at a single spatial scale. In this study, we simultaneously considered a broad range of variables related to climate, topography, land cover, land use, and propagule pressure to predict what areas in the southeastern United States are more susceptible to invasion by 45 invasive terrestrial plant species. Using expert-verified occurrence points from EDDMapS, we modeled invasion susceptibility at 30-m resolution for each species using a maximum entropy (MaxEnt) modeling approach. We then analyzed how environmental predictors affected susceptibility to invasion at different spatial scales. Climatic and land-use variables, especially minimum temperature of coldest month and distance to developed areas, were good predictors of landscape susceptibility to invasion. For most of the species tested, human-disturbed systems such as developed areas and barren lands were more prone to be invaded than areas that experienced minimal human interference. As expected, we found that landscape heterogeneity and the presence of corridors for propagule dispersal significantly increased landscape susceptibility to invasion for most species. However, we also found a number of species for which the susceptibility to invasion increased in landscapes with large core areas and/or less-aggregated patches. These exceptions suggest that even though we found the expected general patterns for susceptibility to invasion among most species, the influence of landscape composition and configuration on invasion risk is species specific.
The Spoon-billed Sandpiper Calidris pygmaea is a ‘Critically Endangered’ migratory shorebird. The species faces an array of threats in its non-breeding range, making conservation intervention essential. However, conservation efforts are reliant on identifying the species’ key stopover and wintering sites. Using Maximum Entropy models, we predicted Spoon-billed Sandpiper distribution across the non-breeding range, using data from recent field surveys and satellite tracking. Model outputs suggest only a limited number of stopover sites are suitable for migrating birds, with sites in the Yellow Sea and on the Jiangsu coast in China highlighted as particularly important. All the previously known core wintering sites were identified by the model including the Ganges-Brahmaputra Delta, Nan Thar Island and the Gulf of Mottama. In addition, the model highlighted sites subsequently found to be occupied, and pinpointed potential new sites meriting investigation, notably on Borneo and Sulawesi, and in parts of India and the Philippines. A comparison between the areas identified as most likely to be occupied and protected areas showed that very few locations are covered by conservation designations. Known sites must be managed for conservation as a priority, and potential new sites should be surveyed as soon as is feasible to assess occupancy status. Site protection should take place in concert with conservation interventions including habitat management, discouraging hunting, and fostering alternative livelihoods.
We aimed to describe the clinical features in coronavirus disease 2019 (COVID-19) cases. We studied 134 critically ill COVID-19 cases from 30 December 2019 to 20 February 2020 in an intensive care unit (ICU) at Wuhan Jinyintan Hospital. Demographics, underlying diseases, therapy strategies and test results were collected and analysed from patients on admission, admission to the ICU and 48 h before death. The non-survivors were older (65.46 (s.d. 9.74) vs. 46.45 (s.d. 11.09)) and were more likely to have underlying diseases. The blood group distribution of the COVID-19 cases differed from that of the Han population in Wuhan, with type A being 43.85%; type B, 26.92%; type AB, 10% and type O, 19.23%. Non-survivors tend to develop more severe lymphopaenia, with higher C-reactive protein, interleukin-6, procalcitonin, D-dimer levels and gradually increased with time. The clinical manifestations were non-specific. Compared with survivors, non-survivors more likely to have organ function injury, and to receive mechanical ventilation, either invasively or noninvasively. Multiple organ failure and secondary bacterial infection in the later period is worthy of attention.
Horizontal and vertical distribution of cephalopod paralarvae (PL) from the Mesoamerican Barrier Reef System (MBRS) in the Western Caribbean was studied during two oceanographic cruises in 2006 and 2007. A total of 1034 PL belonging to 12 families, 22 genera, 24 species, 5 morphotypes and a species complex were identified. Abralia redfieldi, Onychoteuthis banksii and Ornithoteuthis antillarum were the most abundant taxa. The taxonomic identification from these three species was corroborated with DNA barcoding (99.8–100% of similarity). Paralarvae of Octopus insularis were reported for the first time in the wild. Most PL occupied the Caribbean Surface Water mass in the 0–25 m depth stratum. Largest paralarval abundances were related to local oceanographic features favouring retention such as the Honduras Gyre and Cozumel eddy. No day-night differences were found in PL abundance, although Abralia redfieldi showed evidence of diel vertical migration. Distribution of PL in epipelagic waters of the MBRS was probably related to ontogenetic migration, hydrographic features of meso and subscale, and to the circulation regimes dominated by the Yucatan Current. The MBRS represents an important dispersion area for PL, potentially connecting a species-rich Caribbean community with the Gulf of Mexico and Florida waters.
A Markov tree is a random vector indexed by the nodes of a tree whose distribution is determined by the distributions of pairs of neighbouring variables and a list of conditional independence relations. Upon an assumption on the tails of the Markov kernels associated to these pairs, the conditional distribution of the self-normalized random vector when the variable at the root of the tree tends to infinity converges weakly to a random vector of coupled random walks called a tail tree. If, in addition, the conditioning variable has a regularly varying tail, the Markov tree satisfies a form of one-component regular variation. Changing the location of the root, that is, changing the conditioning variable, yields a different tail tree. When the tails of the marginal distributions of the conditioning variables are balanced, these tail trees are connected by a formula that generalizes the time change formula for regularly varying stationary time series. The formula is most easily understood when the various one-component regular variation statements are tied up into a single multi-component statement. The theory of multi-component regular variation is worked out for general random vectors, not necessarily Markov trees, with an eye towards other models, graphical or otherwise.
To compare the effects of a typical Food Distribution Program on Indian Reservations (FDPIR) diet with an FDPIR diet that meets Dietary Guidelines for Americans (DGA) on inflammation response, appetite and energy intake on a combination of American Indian (AI) and non-AI individuals.
A within-subjects, randomised, crossover design was used to compare two dietary conditions: (1) a FDPIR diet that met DGA and (2) a FDPIR diet that did not meet DGA. Each participant served as their own control and was exposed to both dietary conditions. Repeated-measures ANOVA and t tests assessed significance between the two dietary conditions.
This took place in the Montana State University Nutrition Research Laboratory in the USA.
Female and male participants (n 13) aged 18–55 years from the university and local community.
There were no significant differences in inflammatory response and appetite sensations between the two dietary conditions. Findings indicated that participants ate 14 % more (P < 0·01) kcal on a typical FDPIR diet compared with a FDPIR diet that met DGA.
Higher energy intake during a typical FDPIR diet compared with a FDPIR diet that meets DGA may increase risk for obesity and nutrition-related diseases, including type 2 diabetes and other chronic inflammatory conditions.
Seabirds face a diverse array of threats and are considered to comprise one of the most threatened avian groups globally. Development of appropriate conservation action requires a knowledge of the marine distribution of seabirds, furnished either by tracking the movements of individuals, or from at-sea surveys. Obtaining information on the distribution of the smallest seabird species, the storm-petrels Hydrobatidae, is challenging, but the recent development of <1 g GPS tracking tags now enables high-precision tracking and this study reports the first multi-year high-precision tracking of European Storm-petrels Hydrobates pelagicus from their largest UK breeding colony. A total of 42 successful tag deployments were made over four breeding seasons during incubation, brooding and post-brood phases, and there was no evidence of adverse impacts on adult body mass or nest survival rates. Foraging trips lasted between one and three days and ranged up to 397 km from the colony (median = 159 km). Foraging range and total distance covered were positively correlated with trip duration but did not differ across breeding stages. Storm-petrels did not feed to the west of the colony at the edge of the continental shelf where high concentrations have been reported in previous decades from boat surveys, but rather, foraging was restricted to shallow waters south of the colony, consistent across individuals, breeding stages and years. Two areas were identified that exceed the threshold criteria for marine Important Bird Area status and should be considered for statutory protection. The home range estimated across all three breeding stages overlapped with 206 active hydrocarbon wells and 14 operating platforms which represent potential threats as sources of surface pollution or through attraction of birds to gas flares. Improved understanding of the foraging distribution of storm-petrels from this protected colony greatly assists the identification of potential threats and informs appropriate marine spatial planning.
This article investigates the long-time behavior of conservative affine processes on the cone of symmetric positive semidefinite
matrices. In particular, for conservative and subcritical affine processes we show that a finite
-moment of the state-independent jump measure is sufficient for the existence of a unique limit distribution. Moreover, we study the convergence rate of the underlying transition kernel to the limit distribution: first, in a specific metric induced by the Laplace transform, and second, in the Wasserstein distance under a first moment assumption imposed on the state-independent jump measure and an additional condition on the diffusion parameter.