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In recent times, clash after clash has arisen between herdsmen and farmers in Nigeria. These conflicts were linked to the effects of climate change in northern Nigeria, but have been exacerbated by other factors including ethno-religious sentiments. Herdsmen forced to migrate southwards face intense competition for arable and grazing land with the farmers in Nigeria's middle belt. This invariably leads to conflicts, often resulting in gruesome murder and carnage. Thousands have died, many more have been maimed and millions displaced because of this crisis. As a solution, the Nigerian government proposes to set up grazing reserves and rural grazing area settlements in all states of the federation. The problem with this proposal is how and where to obtain the land. This article reflects on the legal implications of the proposal and argues in favour of grazing reserves and ranching on the basis of a private freehold / leasehold tenure arrangement, not through the compulsory acquisition of land by the government.
Chapter 8 studies the record of macroeconomic and financial crises, high inflation episodes, currency collapses, political crises, and collapses of democracy in Latin America and the financial crises and recession episodes in East Asian economies in the period 1970–2015. The chapter focuses on countries – such as Argentina and Venezuela – with high incidence of growth, inflation, and political crises, and also examines the cases of Chile and Mexico. The chapter examines the effects of the East Asian crisis of 1997–98 on Korea, Indonesia, the Philippines, Thailand, and Malaysia (the Asia-5 countries) and compares its impact on China, Vietnam, Singapore, and Hong Kong. The chapter offers a discussion on a wide variety of crisis and stabilization occurrences in a comparative perspective, highlighting economic and political economy factors.
Protected area systems include sites preserved by various institutions and mechanisms, but the benefits to biodiversity provided by different types of sites are poorly understood. Protected areas established by local communities for various reasons may provide complementary benefits to those established by large-scale agencies and organizations. Local communities are geographically constrained, however, and it remains unclear how effectively they protect biodiversity. We explored this issue by focusing on protected areas established through direct democracy via local ballot initiatives whereby communities vote to tax themselves for open space preservation. We compared the effectiveness of local ballot-protected areas to areas protected by a large-scale conservation actor, The Nature Conservancy (TNC). We evaluated how well the two protected area types correspond with amphibians, reptiles, birds, mammals and special status elements of natural diversity. Local ballot-protected areas differed from those of TNC in terms of size, location, proximity to urban areas and habitat diversity. In terms of potential habitat coverage, local ballot-protected areas outperformed TNC sites for all species groups with the exception of special status elements of natural diversity. While not necessarily targeting wildlife and habitats, we conclude that locally established protected areas can make an important contribution to biodiversity conservation.
In this chapter we introduce equity-linked insurance contracts. We explore deterministic emerging costs techniques with examples, and demonstrate that deterministic profit testing cannot adequately model these contracts.
We introduce stochastic cash flow analysis, which gives a fuller picture of the characteristics of the equity-linked cash flows, particularly when guarantees are present, and we demonstrate how stochastic cash flow analysis can be used to determine better contract design.
Finally we discuss the use of quantile and conditional tail expectation reserves for equity-linked insurance.
In this chapter we introduce the concept of a policy value for a life insurance policy. Policy values are used to determine the economic or regulatory capital needed to remain solvent, and also to determine the profit or loss for the company over any time period.
We define the policy value as the expected value of future net cash flows for a policy in force, and distinguish gross premium policy values, which explicitly allow for expenses and for the full gross premium, from net premium policy values, where expenses are excluded from the outgoing cash flows, and only the net premium is counted as income.
We show how to calculate policy values recursively, and how to analyse profit by source. We derive Thiele's differential equation for policy values -- the continuous time equivalent of the recursions for policies with annual cash flows.
We consider how policy values can be used as the basis for policy alterations.
We show how a retrospective valuation has connections both with asset shares and with the policy values . Finally, we define modofied net premium policy values, and consider specifically the Full Preliminary term reserve.
We present an actuarial claims reserving technique that takes into account both claim counts and claim amounts. Separate (overdispersed) Poisson models for the claim counts and the claim amounts are combined by a joint embedding into a neural network architecture. As starting point of the neural network calibration, we use exactly these two separate (overdispersed) Poisson models. Such a nested model can be interpreted as a boosting machine. It allows us for joint modeling and mutual learning of claim counts and claim amounts beyond the two individual (overdispersed) Poisson models.
Fifty-one Churra da Terra Quente ewes (4–7 years old) were used to analyse the potential of real-time ultrasound (RTU) to predict the amount of internal adipose depots, in addition to carcass fat (CF). The prediction models were developed from live weight (LW) and RTU measurements taken at eight different locations. After correlation and multiple linear regression analysis, the prediction models were evaluated by k-fold cross-validation and through the ratio of prediction to deviation (RPD). All prediction models included at least one RTU measurement as an independent variable. Prediction models for the absolute weight of the different adipose depots showed higher accuracy than prediction models for fat content per kg of LW. The former showed to be very good or excellent (2.4 ⩽ RPD ⩽ 3.8) for all adipose depots except mesenteric fat (MesF) and thoracic fat, with the model for MesF still providing useful information (RPD = 1.8). Prediction models for fat content per kg of LW were also very good or excellent for subcutaneous fat, intermuscular fat, CF and body fat (2.6 ⩽ RPD ⩽ 3.2), while the best prediction models for omental fat, kidney knob, channel fat and internal fat still provided useful information. Despite some loss in the accuracy of the estimates obtained, there was a similar pattern in terms of RPD for models developed from LW and RTU measurements taken just at the level of the 11th thoracic vertebra. In vivo RTU measurements showed the potential to monitor changes in ewe internal fat reserves as well as in CF.
Breeding for resilience requires a better understanding of intra-flock variability and the related mechanisms responsible for robustness traits. Among such traits, the animals’ ability to cope with feed fluctuations by mobilizing or restoring body reserves (BR) is a key mechanism in ruminants. The objective of this work was to characterize individual variability in BR dynamics in productive Romane ewes reared in extensive conditions. The BR dynamics profiles were characterized by combining individual longitudinal measurements of BW and body condition scores (BCS) over several production cycles. Historical data, including up to 2628 records per trait distributed in 1146 ewes, underwent cluster analysis. Two to four trajectories were observed for BW depending on the cycle, while three trajectories were found for BCS, whatever the cycle. Most trajectories suggested that BR dynamics were similar but the level of BR may differ between ewes. Nevertheless, some trajectories suggested that both BR dynamics and levels were different for a proportion of ewes. Clustering on BW and BCS profiles adjusted for individual level trends, resulted in differences only in the level of BW or BCS, rather than differences in trajectories. Thus, the overall shape of trajectories was not changed considering or not the individual level trend across cycles. In addition to individual variability, the ewe’s age at first lambing and litter size contributed to the distribution of the ewes between the trajectories. Regarding the entire productive life, three trajectories were observed for BW and BCS changes over three productive cycles. Increase in BW at each cycle suggested that ewes kept growing up until 3 to 4 years old in our conditions. Similar alternation of BCS gains and losses across cycles suggested BR dynamics might be repeatable. Many individual trajectories remained the same throughout a ewe’s life, whatever the age at first lambing, parity or litter size. Our results demonstrate the relevance of using BW and BCS changes for characterizing the diversity of BR mobilization–accretion profiles in sheep in a long timespan perspective.
People's relationships with trees reflect the landscape histories associated with distinctive forms of political and religious authority and the moral imaginings of people in Nangodi and its environs in the Upper East Region of Ghana. Their memories of particular trees serve as historical evidence of overlapping yet specific forms of political authority exercised by chiefs, earth priests, past colonial officers, and present-day Ghanaian government officials. In Nangodi, individual family ancestral tree shrines, clan tree cemeteries, and sacred groves associated with earth priests and chiefs coexist with the Red Volta West Forest Reserve and with a succession of tree-related development initiatives. While these relationships are often considered as separate claims to political authority, spiritual power, or scientific knowledge, this paper argues that these relationships of people and of trees are better conceptualized as historical accumulations that represent intersecting and contested forms of authority and political rule continuing into the present. Indigenous tree species such as ebony are associated with sacred groves controlled by chiefs, silk-cotton trees with earth priests’ cemeteries, and baobab trees with particular families coexist with foreign teak trees associated with colonial forestry. This situation suggests how institutions of governance as well as the actions of individuals have environmental consequences. A consideration of historical memories of people and trees in places such as Nangodi enables a rethinking of political and environmental dichotomies, and complicates the social dynamics of` the preservation and destruction of trees and forests around the world.
A divergent selection experiment on litter size variability (high and low lines) was performed in rabbits over seven generations. The aim of this study was to evaluate the correlated responses to selection in body condition and fat reserves mobilisation. Litter size variability was estimated as phenotypic variance of litter size within female after correcting for the year-season and the parity-lactation status effects. A total of 226 females were used in this study, of which 158 females were used to measure body condition and energy mobilisation. Body condition was measured as BW and perirenal fat thickness. Females were stimulated with the adrenergic isoproterenol. Mobilisation capacity of fat reserves was measured by the lipolytic potential, defined as the increment in non-esterified fatty acids (NEFA) levels from basal concentration until adrenergic stimulation at mating, delivery and 10 days after delivery of the second reproductive cycle. Females were classified as survivor or non-survivor when they were culled for sanitary reasons or died before the third kindling. Data were analysed using Bayesian methodology. Survivor females presented higher BW than the non-survivor females at delivery (238 g, P=1.00) and 10 days after delivery (276 g, P=1.00). They also showed higher perirenal fat thickness at 10 days after delivery (0.62 mm, P=1.00). At delivery, basal NEFA levels was lower in survivor than non-survivor females (−0.18 mmol/l, P=1.00), but their lipolytic potential (∆NEFA) was higher (0.08 mmol/l, P=0.94). Body weight was similar between lines in survivor females. Perirenal fat thickness was lower in the high line than in the low line at delivery (−0.23 mm, P=0.90) and 10 days after delivery (−0.28 mm, P=0.92). The high line exhibited higher NEFA (0.10 mmol/l, P=0.93) and lower ∆NEFA (−0.08 mmol/l, P=0.92) than the low line at delivery. The low line showed a favourable correlated response to selection on body condition and fat reserves mobilisation. In conclusion, the low line selected for litter size variability seems to adapt better to adverse conditions, as it has a greater capacity to mobilise energy reserves at delivery than the high line. Females that adequately manage their body reserves and perform energy mobilisation correctly have a lower risk of dying or being culled.
Food uncertainty has the effect of invigorating food-related responses. Psychologists have noted that mammals and birds respond more to a conditioned stimulus that unreliably predicts food delivery, and ecologists have shown that animals (especially small passerines) consume and/or hoard more food and can get fatter when access to that resource is unpredictable. Are these phenomena related? We think they are. Psychologists have proposed several mechanistic interpretations, while ecologists have suggested a functional interpretation: The effect of unpredictability on fat reserves and hoarding behavior is an evolutionary strategy acting against the risk of starvation when food is in short supply. Both perspectives are complementary, and we argue that the psychology of incentive motivational processes can shed some light on the causal mechanisms leading animals to seek and consume more food under uncertainty in the wild. Our theoretical approach is in agreement with neuroscientific data relating to the role of dopamine, a neurotransmitter strongly involved in incentive motivation, and its plausibility has received some explanatory and predictive value with respect to Pavlovian phenomena. Overall, we argue that the occasional and unavoidable absence of food rewards has motivational effects (called incentive hope) that facilitate foraging effort. We show that this hypothesis is computationally tenable, leading foragers in an unpredictable environment to consume more food items and to have higher long-term energy storage than foragers in a predictable environment.
On November 25, 2015, the Inter-American Court of Human Rights (Court) held that the state of Suriname had violated the rights of two indigenous groups by denying recognition of their juridical personality and their entitlement to collective property and judicial protection. In Kaliña and Lokono Peoples v. Suriname, the Court also considered the impact of nature reserves on indigenous land rights, as well as the legitimacy of private titling of property that encroaches on land for which collective title has not been attained. The decision pushes the Court's previous jurisprudence significantly—and somewhat controversially—by asserting that under the American Convention on Human Rights, indigenous peoples are entitled, as collective entities, to recognition of their legal personality. In so doing, the Court challenged ordinary assumptions about the individualized character of most adjudication regarding international human rights and made the possibility of enforcing collective rights more palpable.
Early plant establishment through seed germination and seedling emergence is a crucial process that determines seedling number, emergence time distribution and the early growth of seedlings, all of which are affected by soil climate and soil structure. In the current context of climate change, in which increasing the diversity of cultivated species is considered desirable, and new tillage practices are considerably modifying top-soil surface characteristics, we need to improve our ability to model the effects of the environment on plant establishment. Using a trait-based and model-based framework, we aimed to identify general relationships between seed and seedling traits (e.g. seed mass and lipid content, seedling diameter, base temperature) and germination and emergence model parameters (e.g. time to mid-germination, shoot elongation rate) measured for 18 genotypes belonging to 14 species. Relationships were also investigated among model parameters or traits. Germination rates were faster for species with a high base temperature and for species with seed reserves located principally in the embryo (rather than the endosperm or perisperm). During heterotrophic growth, maximal shoot length and elongation rate increased with seed dry mass. The sensitivity of seedlings to soil obstacles was negatively related to shoot diameter. Thus apart from the known effects of seed mass on seedling establishment, we found that seed reserve location, seedling shoot diameter and shape affected germination rate and emergence success. Such generic rules linking plant traits to germination and emergence parameters enhance our understanding of the determinants of environmental effects on plant establishment success.
This is the first study of the metabolic enzyme activity and energy state of the dwarf oyster Ostrea stentina (Payraudeau, 1826) in Tunisia and in the Mediterranean region. The main purpose of this study was to examine the modulation of the physiological status of the oyster O. stentina depending on the season and the presence of parasite Marteilia refringens. The prevalence of bonamiosis and marteiliosis were established by PCR. Bonamia exitiosa was detected only in 2.91% of oysters while the prevalence of M. refringens was 100% (30 Ind./30) in February and 93.93% (28 Ind./30) in March. A 42–87% mortality rate was reported during the study period. Biochemical analyses were carried out to evaluate the management of the energy resources in regard to the biochemical changes of lipids and carbohydrates. The enzyme activity of pyruvate kinase (PK), citrate synthase (CS) and cytochrome c oxidase (CCO) were measured and the mean level of enzyme activity was respectively 20.31 mU mg−1 protein; 12.06 mU mg−1 protein and 3.59 mU mg−1 protein. Carbohydrate contents of O. stentina were very low all year round with an average of 15.18% in dry weight, and lipid contents remain similar (11.77% in dry weight) compared with the values reported for most other temperate bivalves. Enzyme activity significantly decreased over time (P < 0.001). The energy resources of the oyster O. stentina wherein much of the energy was devoted to reproduction seem to affect the defence system.
For parasitoids, the host represents the sole source of nutrients for the developing immature. Subsequently, host quality is an important factor affecting immature development and the resulting fitness of the emerging parasitoid, with impacts on fecundity, longevity and offspring sex ratio. Host age is an integral component of host quality and a key factor in host selection by the female parasitoid. The current study aimed to investigate the effect of decreasing host quality (determined by increasing host age) on adult life history traits (size, wing loading, longevity, and fecundity) and nutritional reserves (protein, lipid and glycogen concentrations) of the parasitoid Trichogramma brassicae. Higher quality hosts resulted in the production of larger offspring with increased resource reserves and enhanced mobility. One-day-old eggs contained significantly more protein and triglyceride than 25- and 45–day-old eggs. Quality of host and fitness of reared wasps decreased due to host aging. Parasitoids reared on 1-day-old hosts were larger, with greater fecundity and longevity, a reduced wind loading index, and produced a higher proportion of female offspring when compared with those reared on 25- and 45-day-old hosts. In addition, wasps reared on 1-day-old hosts contained higher energy resources, as determined by triglyceride, glycogen and protein reserves, which are essential to successful offspring production. One-day-old hosts can therefore be considered as the best age for producing wasps with greater fitness, since they contain the highest amount of protein, glycogen, and triglyceride. This has implications for the mass rearing of T. brassicae and enhancing the efficacy of this biological control agent.
Since the onset of the Federal Reserve's unconventional programme of large-scale asset purchases, known as quantitative easing (QE), some economists and financial practitioners have feared that the consequent buildup of the Fed's balance sheet could lead to a large expansion of the money supply, and that such an increase could cause a sharp rise in inflation. So far fears about induced inflation have not been validated. This article examines the basis for the original concerns about inflation in terms of the classic quantity theory of money, which holds that inflation occurs when the money supply expands more rapidly than warranted by increases in real production. The article first reviews the US experience and shows that whereas rapid money growth might have been a plausible explanation of inflation in the 1960s through the early 1980s, subsequent data have not supported such an explanation. It then shows that the quantity theory of money has not really been put to the test after the Great Recession, because a sharp increase in banks’ excess reserves and corresponding sharp decline in the ‘money multiplier’ has meant that the rise in the Federal Reserve's balance sheet has not translated into increased money available to the public in the usual fashion. The most likely aftermath of quantitative easing remains one of benign price behaviour. However, if nascent inflationary conditions materialise, the Federal Reserve will need to manage adroitly the large amounts of banks’ excess reserves that have accumulated as a consequence of QE in order to limit inflationary pressures.
Isolation can provide marine ecosystems with a refuge from human impacts. However, information on the biodiversity, ecology and fisheries of remote regions is often sparse. The proposed Coral Sea Marine Reserve could create one of the world's largest and most remote marine parks, yet little information is available to inform discussions. Fish captures from the Coral Sea and adjacent Great Barrier Reef (GBR) were assessed from reports contained in a chronology of spearfishing publications from 1953 to 2009, and reveal for the first time the history of recreational spearfishing in the Coral Sea. Although the area is perceived as relatively untouched, the data indicate that spearfishers have frequented Coral Sea reefs for at least 43 years and reported captures have increased exponentially. Post-1993 trophy captures in the Coral Sea (mean 23 kg) were larger than the adjacent GBR (9 kg). Reef species characterize the GBR catch, while large pelagic species characterize the Coral Sea catch. Provided that functionally important fishes are not targeted, the relatively small scale of recreational spearfishing and the focus on pelagic species suggests that spearfishing currently exerts limited pressure on the ecology of Coral Sea reefs.
We report 37 species of heterobranch sea slugs from the National Park Alacranes reef, located in the Campeche Bank, at the south-eastern Gulf of Mexico, of which 18 species are reported for the first time in this reef. With this contribution, the species richness in this national park increases to up to 67. The species Nakamigawaia felis, Petalifera sp., Elysia flava, Elysia pratensis and Bulbaeolidia sp. are reported in the Gulf of Mexico for the first time. The geographical distribution ranges for Oxynoe azuropunctata, Elysia ornata, Placida kingstoni, Aphelodoris antillensis and Tritonia hamnerorum are extended westward. Those for Elysia flava, Pleurobranchus areolatus and Felimare ruthae are extended both northward and westward.
The claims development result (CDR) is the difference between the best estimate predictions of the ultimate claim in 2 successive years. With best estimate reserves it is often argued that CDR’s in consecutive years should fluctuate randomly around zero. However, in practice one frequently observes that CDR’s in a given line of business have the same sign over several consecutive years. We show that this is a phenomenon which is not unusual and to be expected in situations of change. Moreover, we show how situations of change can adequately be described by a model, taking into account the evolving external information.
Marine protected areas (MPAs) are increasingly being considered and used for the management of fisheries targeting mobile fish populations. Here, the recent modelling literature on MPA effects for mobile fish populations and their fisheries is reviewed. Modelling studies conducted since 2011 have filled a considerable number of knowledge gaps on the impacts of MPAs for species exhibiting home-range behaviour, nomadic movements or behavioural polymorphism, and on the effects of “targeted MPAs”, which aim to protect relatively small areas where migratory fishes spend an inordinate fraction of time or are highly vulnerable to fishing (e.g., nursery or spawning zones). Also, in recent years, two studies investigated the consequences of MPAs targeting highly migratory (tuna-like) fish populations for the first time in the history of MPA modelling. Recent modelling studies found that MPAs aimed at protecting mobile species may have positive conservation effects under a relatively wide range of situations, but may generate long-term fisheries benefits only under a very limited set of conditions. In particular, MPAs were not found to be beneficial for the fisheries targeting highly migratory populations. Strategies producing both conservation and fisheries benefits were identified, which depend on fish movement patterns and numerous aspects of fish life history and fisheries dynamics. However, in view of the diversity of fish movement patterns in MPA systems and current dynamics in resource management, it is clear that additional modelling work is needed to fully understand how protected areas affect mobile fish populations and their fisheries and to be able to implement pertinent MPAs. In particular, future modelling studies should systematically assess the effects of MPAs in relation to other management tools to find strategies that are most effective in meeting management objectives, and explore the impacts of “dynamic” MPAs that follow highly migratory fish populations in space and time.