The Dilemma of Tax Competition: How (not) to attract (Inefficient) Firms?

We consider a tax competition game between asymmetrically un-informed governments. Two governments simultaneously propose tax arrangements to attract a multinational firm (MNF) which has an ex-ante preference to operate in both countries, and governments anticipate that once the MNF accepts their offer, each host will know the marginal cost of local production, but not the marginal cost in the other country. We show that when the multinational prefers to operate in both countries or not operate at all, then the tax competition game features two equilibria. In one equilibrium, efficient MNFs are attracted in the two countries, while in the other equilibrium, inefficient MNFs are attracted. The equilibrium in which only efficient firms are attracted may occur as the unique outcome if the MNFs can ultimately decide to settle in one country only. Our results suggest that, the existence of (small) countries who are aggressive in attracting MNFs by offering substantial tax advantages allows competing governments to keep inefficient firms away from their territories.Common Agency;Adverse Selection;tax competition;Multinationals

Competition, Incomplete Discrimination and Versioning

Producers of software viewers commonly other basic versions of their products for free while more sophisticated versions are highly priced, thereby providing less attractive or lower valuations consumers with larger utility levels.We give some foundations to this outcome called versioning.We consider a duopoly in which firms other di erentiated goods to a representative consumer; the buyer has distinct marginal valuations for the quality of the products; each producer perfectly knows the consumers taste for its own product, but remains uninformed about its taste for the rivals product.When each product cannot be purchased in isolation of the other one, a phenomenon of endogenous preferences arises since a firms o er to the consumer depends on the information unknown by the rival firm.Multiple equilibria emerge and the consumers rent increases with his valuation for one product and decreases with the valuation for the other product.By contrast, when each product can be purchased in isolation of the other one, at the unique equilibrium consumers with larger valuations for a product earn higher rents.The analysis is undertaken under two alternative pricing policies: in the partially-discriminatory case, producers make use of the known information only; in the fully-discriminatory case, each producer second-degree price discriminates the consumer according to the unknown information.We show that, sometimes, firms prefer partial to full discrimination, i.e., strategic ignorance of consumers tastes for the rival brand softens competition.competition;prices

Étude expérimentale des transferts d'eau provoqués par l'irrigation sur une parcelle en moyenne vallée du fleuve Sénégal

Alors que l'irrigation paraît être le recours essentiel face aux besoins croissants de la population mondiale en céréales, la dégradation des sols et des eaux annihile presque totalement les efforts d'aménagement. Aussi l'étude de la dégradation des sols dans la moyenne vallée du fleuve Sénégal constitue l'un des quatre objectifs du pôle de recherches sur les systèmes irrigués sahéliens qui regroupe quatre pays dont le Mali, la Mauritanie, le Niger et le Sénégal. Le suivi de l'évolution des eaux et des sols sous culture apparaît indispensable pour garantir une agriculture irriguée rentable et durable dans la zone. Dans cette région, les risques de dégradation des sols font suite à l'effet de deux processus de dégradation que sont l'alcalinisation et la salinisation des sols. Ces types de dégradation sont fortement corrélés à la remontée des nappes d'eaux souterraines. Dans cet article, l'étude des transferts d'eau dans les parcelles irriguées par le biais d'un suivi expérimental " in situ " met en évidence les relations existantes entre les eaux d'irrigation et les mouvements de la nappe. L'étude a permis une meilleure compréhension de la dynamique hydrique au sein de la parcelle : saturation du profil et processus de recharge de la nappe. Elle a également permis de montrer que les échanges avec la nappe pendant la période d'irrigation sont négligeables. Cette pratique de la riziculture inondée, entraîne une variation de stock importante qui représente plus de 40% des apports et qui se traduit par une remontée de nappe de près de 2 mètres.Whereas irrigation appears to be the main approach to satisfy the growing worldwide demand for cereal, soil and water degradation continues to be an on-going problem in agriculture development. One of the main four concerns of the regional group for research on Sahelian irrigated systems (including Mali, Mauritania, Niger and Senegal) is soil degradation in the middle Senegal River valley. These soils are subject to various forms of degradation, mainly from salinisation and/or alkalinisation. These degradation processes are strongly correlated with water table dynamics, with water level fluctuations being significant. Therefore, to guarantee sustainable development of irrigated agriculture in the area, irrigation must be coupled with complete and permanent monitoring of soil and water quality.In this paper, we present a complete study concerning water transfer in irrigated plots and its effects on the groundwater table. The experimental site is located in the Podor region, at 16°.37'N, 14°.52'W in the Donaye irrigated area. The surface area is about 50 ha. Water supply is assured by filling a main channel using a group of pumps on the Doué River. Irrigation of the parcels is performed with siphons from this channel. The experimental plot of 0.33 ha is used for an underwater rice crop. One or two rice crop production harvests are made every year, with the decision been taken by the farmers. There is no drainage system in the area.The experimental plot was equipped with 8 piezometers located along a stream line. One is situated between the plot and the river in order to study the water movements caused by the exchange between the groundwater and the water in the river. Three are situated in the plot, one close to the Doué River, one in the middle of the plot and one near a dam, which is the opposite boundary compared to the river. Four other piezometers are located beyond the dam to estimate groundwater input and output at this boundary. Five tensiometers at 20, 40, 60, 95 and 135 cm depth are placed close to the piezometers located in the plot. Four water content profiles were measured during the irrigation period at depths 20, 40, 60 95 and 135 cm and the irrigation was performed over 84 days.The water table level variations at 2 meters were recorded. The groundwater inflow decreased during the first part of the irrigation period due to infiltration below the irrigated experimental plot. This inflow increased during a second period due to water level variations in the river close to this site. At the output, the head gradient did not vary appreciably and the outflow was assumed to be constant during the observation period. Moreover, this gradient is quite low and the flow rate is very low. The water content and pressure profiles clearly show the infiltration of water in the soil during irrigation. The head gradients show the water movement in the unsaturated soil during infiltration and evaporation. Upward flow due to evaporation is observed at about 10 days after irrigation. The last measured water profile (76 days after the end of irrigation) shows that evaporation modifies the water content profile until at least a depth of 120 cm.The water balance during the irrigation period showed that the input due to irrigation and precipitation was equal to 4150 m3. The evapotranspiration output was estimated to be 2370 m3. Groundwater exchange at the downstream boundary can be neglected during the duration of irrigation (84 days), since the average hydraulic gradient remained low (less than 0.8 %) and the hydraulic conductivity of the aquifer was not important (about 250 cm/day). It was assumed that the water storage quantified with the rise of the groundwater level was equal to the difference between surface input and evapotranspiration (more than 40 % of the contributions), leading to a 27 % change in water content, which is quite reasonable for this type of soil (clay).The stored water was then recovered by evapotranspiration and groundwater outflow at the plot boundaries. We are away from a reasonable irrigation that would reduce the used water quantity and decrease the risk of soil degradation. This study allows a better understanding of the water dynamics in the experimental plot, which includes soil saturation, recharge processes, and exchanges between the aquifer and the river

Diseño de Plataformas Moleculares Multifuncionales

El boro es un elemento que forma compuestos químicos que presentan enlaces de tres centros y dos electrones, de tipo B-H-B o B-B-B como, por ejemplo, el anión octahidrotriborato, B3H8-.El anión octahidrotriborato es un compuesto muy importante en la química del boro, ya que es un intermedio de reacción en la síntesis de boranos superiores y de diversos complejos de metales de transición. También cabe destacar que este anión, en disolución, es fluxional, ya que todos los átomos de hidrógeno, presentes en la molécula, se intercambian en el tiempo de escala de los experimentos de Resonancia Magnética Nuclear (RMN) de 1H; el mecanismo de intercambio que se ha propuesto en la bibliografía consiste en una pseudorrotación del grupo BH2.Una de las formas más estables en las que se puede encontrar el anión es como CsB3H8 o ((n-С4H9)4N)[B3H8]. Estas sales se pueden utilizar para sintetizar metalaboranos de B3H8-, que son complejos de metal en donde el anión triborato funciona como ligando. Una síntesis interesante de este tipo es la que ha permitido obtener la molécula de rodatetraborano, [Rh(η2-B3H8)(H)2(PPh3)2].El rodatetraborano es un complejo de Rh(III) en donde el B3H8-, actúa como un ligando quelato bidentado. Este metalaborano, en disolución, también presenta comportamientos fluxionales, que han sido estudiados y caracterizados por RMN. A temperaturas superiores a los 290 K, se produce la apertura de los enlaces B-H-B y la migración de los átomos de H terminales de manera sincronizada.<br /

In-situ fluorescence spectroscopy indicates total bacterial abundance and dissolved organic carbon

We explore in-situ fluorescence spectroscopy as an instantaneous indicator of total bacterial abundance and faecal contamination in drinking water. Eighty-four samples were collected outside of the recharge season from groundwater-derived water sources in Dakar, Senegal. Samples were analysed for tryptophan-like (TLF) and humic-like (HLF) fluorescence in-situ, total bacterial cells by flow cytometry, and potential indicators of faecal contamination such as thermotolerant coliforms (TTCs), nitrate, and in a subset of 22 samples, dissolved organic carbon (DOC). Significant single-predictor linear regression models demonstrated that total bacterial cells were the most effective predictor of TLF, followed by on-site sanitation density; TTCs were not a significant predictor. An optimum multiple-predictor model of TLF incorporated total bacterial cells, nitrate, nitrite, on-site sanitation density, and sulphate (r2 0.68). HLF was similarly related to the same parameters as TLF, with total bacterial cells being the best correlated (ρs 0.64). In the subset of 22 sources, DOC clustered with TLF, HLF, and total bacterial cells, and a linear regression model demonstrated HLF was the best predictor of DOC (r2 0.84). The intergranular nature of the aquifer, timing of the study, and/or non-uniqueness of the signal to TTCs can explain the significant associations between TLF/HLF and indicators of faecal contamination such as on-site sanitation density and nutrients but not TTCs. The bacterial population that relates to TLF/HLF is likely to be a subsurface community that develops in-situ based on the availability of organic matter originating from faecal sources. In-situ fluorescence spectroscopy instantly indicates a drinking water source is impacted by faecal contamination but it remains unclear how that relates specifically to microbial risk in this setting

Epidemiological Interactions between Urogenital and Intestinal Human Schistosomiasis in the Context of Praziquantel Treatment across Three West African Countries

© 2015 Knowles et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article

Vietnam-EU Free Trade Agreement: Impact and Policy Implications for Vietnam

On 4 August 2015, after three years and several rounds of negotiation, the European Union –Vietnam Free Trade Agreement officially established principles for the basic content of the Agreement. This study aims to analyse impact of Vietnam-EU FTA on bilateral trade of Vietnam. By using a gravity model and a panel data analysis, we show that the reduction of tariffs in the framework of the FTA will have a positive impact on bilateral trade between Vietnam and the EU. In addition, Vietnam-EU FTA will offer many new opportunities but it also challenges for Vietnam. Based on these analyses, this paper proposes some recommendations for Vietnam to benefit more the Vietnam-EU FTA

Formamidinium halide salts as precursors of carbon nitrides

13 figures, 6 tables.-- Supplementary information available.Pyrolysis of formamidinium halide salts (FAI, FABr) results in a new type of amorphous carbon nitride materials with a mass fraction of 40–50% nitrogen content. Pyrolysis temperature drives final chemical composition, morphology, optical and electrical properties of the material independently of the halide precursor and identifying triazine ring, instead of typical heptazine unit, as the main building block of this material. We elaborated a temperature dependent mechanism of formation for these materials and foresee its potential value as native passivation layer in the field of perovskite solar cells.E.J.J-P acknowledges the funding support from MCIN/AEI/10.13039/501100011033 and European Union NextGenerationEU/PRTR (project grants PID2019-107893RB-I00 and EIN2020-112315, respectively). M.H. acknowledges the funding support from MCIN/AEI/10.13039/501100011033 for the Ramón y Cajal fellowship (RYC-2018-025222-I) and the project PID2019-108247RA-I00. R.A. acknowledges funding from the Spanish MICINN (project grant PID2019-104739 GB-100/AEI/10.13039/501100011033). RA also acknowledge to Government of Aragon (project DGA E13-20R (FEDER, EU)) and European Union H2020 program “ESTEEM3” (823717). A.A-C acknowledges financial support from Spanish MCIN/AEI/10.13039/501100011033 under project PID2019-104272RB-C51/AEI/10.13039/501100011033 and the Diputación General de Aragón under project T03_20R (Grupo Reconocido).Peer reviewe