The Economics of Roscas and Intra-Household Resource Allocation

This paper investigates individual motives to participate in rotating savings and credit associations (roscas).Detailed evidence from roscas in a Kenyan slum (Nairobi) suggests that most roscas are predominantly composed of women, particularly those living in a couple and earning an independent income. To explain this phenomenon, we propose an argument based on conflictual interactions within the household.Participation in a rosca is a strategy a wife employs to protect her savings against claims by her husband for immediate consumption.The empirical implications of the model are then tested using the data collected in Kenya.Rosca;Gender;Household

The Economics of Roscas and Intra-Household Resource Allocation

This paper investigates individual motives to participate in rotating savings and credit associations (roscas).Detailed evidence from roscas in a Kenyan slum (Nairobi) suggests that most roscas are predominantly composed of women, particularly those living in a couple and earning an independent income. To explain this phenomenon, we propose an argument based on conflictual interactions within the household.Participation in a rosca is a strategy a wife employs to protect her savings against claims by her husband for immediate consumption.The empirical implications of the model are then tested using the data collected in Kenya

A Computational Approach for Designing Tiger Corridors in India

Wildlife corridors are components of landscapes, which facilitate the movement of organisms and processes between intact habitat areas, and thus provide connectivity between the habitats within the landscapes. Corridors are thus regions within a given landscape that connect fragmented habitat patches within the landscape. The major concern of designing corridors as a conservation strategy is primarily to counter, and to the extent possible, mitigate the effects of habitat fragmentation and loss on the biodiversity of the landscape, as well as support continuance of land use for essential local and global economic activities in the region of reference. In this paper, we use game theory, graph theory, membership functions and chain code algorithm to model and design a set of wildlife corridors with tiger (Panthera tigris tigris) as the focal species. We identify the parameters which would affect the tiger population in a landscape complex and using the presence of these identified parameters construct a graph using the habitat patches supporting tiger presence in the landscape complex as vertices and the possible paths between them as edges. The passage of tigers through the possible paths have been modelled as an Assurance game, with tigers as an individual player. The game is played recursively as the tiger passes through each grid considered for the model. The iteration causes the tiger to choose the most suitable path signifying the emergence of adaptability. As a formal explanation of the game, we model this interaction of tiger with the parameters as deterministic finite automata, whose transition function is obtained by the game payoff.Comment: 12 pages, 5 figures, 6 tables, NGCT conference 201

Local and global interactions in an evolutionary resource game

Conditions for the emergence of cooperation in a spatial common-pool resource game are studied. This combines in a unique way local and global interactions. A fixed number of harvesters are located on a spatial grid. Harvesters choose among three strategies: defection, cooperation, and enforcement. Individual payoffs are affected by both global factors, namely, aggregate harvest and resource stock level, and local factors, such as the imposition of sanctions on neighbors by enforcers. The evolution of strategies in the population is driven by social learning through imitation, based on local interaction or locally available information. Numerous types of equilibria exist in these settings. An important new finding is that clusters of cooperators and enforcers can survive among large groups of defectors. We discuss how the results contrast with the non-spatial, but otherwise similar, game of Sethi and Somanathan (American Economic Review 86(4):766–789, 1996)

The Dutch Disease in Reverse: Iceland's Natural Experiment

For a long time, abundant natural resources brought Iceland a high and volatile real exchange rate with adverse effects on manufacturing and services. During 2003-2008, another national treasure, the sovereign’s AAA rating, was used by privatized banks to attract foreign capital, elevating the real exchange rate even further. The financial collapse and the associated collapse of the currency in 2008 left the country with a large foreign debt which offset some of the effect of the natural resources on the real exchange rate. In effect, this was the Dutch disease in reverse as witnessed, in particular, by a massive increase in the number of tourists following the financial collapse. This paper discusses the behavior of the exchange rate of the Icelandic króna before and after 2008 as well as its relationship to natural resources, capital flows, output, exports and imports, including tourism

Vote buying or (political) business (cycles) as usual?

We study the short-run effect of elections on monetary aggregates in a sample of 85 low and middle income democracies (1975-2009). We find an increase in the growth rate of M1 during election months of about one tenth of a standard deviation. A similar effect can neither be detected in established OECD democracies nor in other months. The effect is larger in democracies with many poor and uneducated voters, and in Sub-Saharan Africa, Latin America, and in East-Asia and the Pacific. We argue that the election month monetary expansion is related to systemic vote buying which requires significant amounts of cash to be disbursed right before elections. The finely timed increase in M1 is consistent with this; is inconsistent with a monetary cycle aimed at creating an election time boom; and it cannot be, fully, accounted for by alternative explanations

Freedom, Servitude and Voluntary Labor

We present an economic framework to revisit and reframe some important debates over the nature of free versus unfree labor and the economic consequences of emancipation. We use a simple general equilibrium model in which labor can be either free or coerced and where land and labor will be exchanged on markets that can be competitive or manipulated or via other non-market collusive arrangements. By working with variants of the same basic model under different assumptions about initial economy-wide factor endowments and asset ownership we can compare equilibrium distributional outcomes under different institutional and contractual arrangements including markets with free labor and free tenancy, slavery, and tenancy arrangements with tied labor-service obligations. Analysis of these different contractual and organizational forms yields insights that accord with common sense, but that are often overlooked or downplayed in academic debates, particularly amongst economists

Enlightening the invisible: Applications, limits and perspectives of intraoperative fluorescence in neurosurgery.

The introduction of intraoperative fluorophores represented a significant advancement in neurosurgical practice. Nowadays they found different applications: in oncology to improve the visualization of tumoral tissue and optimize resection rates and in vascular neurosurgery to assess the exclusion of vascular malformations or the permeability of bypasses, with real-time intraoperative evaluations. A comprehensive knowledge of how fluorophores work is crucial to maximize their benefits and to incorporate them into daily neurosurgical practice. We would like to revise here their applications and clinical relevance. A focused literature review of relevant articles dealing with the versatile applications of fluorophores in neurosurgery was performed. The fundamental mechanisms of action of intraoperative fluorophores are enlightened, examining their interactions with target tissues and the principles driving fluorescence-guided surgery. The clinical applications of the principal fluorophores, namely fluorescein sodium, 5-ALA and indocyanine green, are detailed, in regards to the management of vascular malformations, brain tumors and pathologies treated through endoscopic endonasal approaches. Future perspective dealing with the development of new technologies or of new molecules are discussed. By critically assessing the efficacy and applications of the different fluorophores, as well as charting their potential future uses, this paper seeks to guide clinicians in their practice and provide insights for driving innovation and progress in fluorescence-based surgery and research

Update on Neoadjuvant and Adjuvant BRAF Inhibitors in Papillary Craniopharyngioma: A Systematic Review.

Background/Objectives: The recent discovery of BRAF mutation in papillary craniopharyngiomas opened new avenues for targeted therapies to control tumour growth, decreasing the need for invasive treatments and relative complications. The aim of this systematic review was to summarize the recent scientific data dealing with the use of targeted therapies in papillary craniopharyngiomas, as adjuvant and neoadjuvant treatments. Methods: The PRISMA guidelines were followed with searches performed in Scopus, MEDLINE, and Embase, following a dedicated PICO approach. Results: We included 21 pertinent studies encompassing 53 patients: 26 patients received BRAF inhibitors (BRAFi) as adjuvant treatment, while 25 received them as neoadjuvant treatment. In the adjuvant setting, BRAFi were used to treat recurrent tumours after surgery or adjuvant radiation therapy. The most common regimen combined dabrafenib (BRAFi) with trametinib (MEK1 and 2 inhibitor) in 81% of cases. The mean treatment length was 8.8 months (range 1.6 to 28 months) and 32% were continuing BRAFi. A reduction of tumour volume variable from 24% to 100% was observed at cerebral MRI during treatment and volumetric reduction ≥80% was described in 64% of cases. Once the treatment was stopped, adjuvant treatments were performed to stabilize patients in remission in 11 cases (65%) or when a progression was detected in three cases (12%). In four cases no further therapies were administered (16%). Mean follow-up after the end of targeted therapy was 17.1 months. As neoadjuvant regimen, 36% of patients were treated with dabrafenib and trametinib with a near complete radiological response in all the cases with a mean treatment of 5.7 months. The neoadjuvant use of verumafenib (BRAFi) and cometinib (MEK1 inhibitor) induced a near complete response in 15 patients (94%), with a median volumetric reduction between 85% and 91%. Ten patients did not receive further treatments. Side effects varied among studies. The optimal timing, sequencing, and duration of treatment of these new therapies should be established. Moreover, questions remain about the choice of specific BRAF/MEK inhibitors, the optimal protocol of treatment, and the strategies for managing adverse events. Conclusions: Treatment is shifting to a wider multidisciplinary management, where a key role is played by targeted therapies, to improve outcomes and quality of life for patients with BRAF-mutated craniopharyngiomas. Future, larger comparative trials will optimize their protocol of use and integration into multimodal strategies of treatment