Globalization and International Commodity Trade with Specific Reference to the West African Cocoa Producers

Liberalization of tropical agricultural markets has brought globalization, in the sense that all producers now face world rather than domestic prices. Producer prices have tended to rise as a share of fob prices as intermediation costs and tax has declined. However, in conjunction with inelastic demand, the downward shift of the aggregate supply curve results in lower world prices. Farmers therefore get a higher share of a lower price. Cocoa is the market where these changes have been most pronounced. The incidence of the liberalization benefits in cocoa is largely on developed country consumers at the expense of the governments of the exporting countries and farmers in non-liberalizing (non-African) countries. Farmers in liberalized African markets are broadly neither better nor worse off.

From continua to R-trees

We show how to associate an R-tree to the set of cut points of a continuum. If X is a continuum without cut points we show how to associate an R-tree to the set of cut pairs of X.Comment: This is the version published by Algebraic & Geometric Topology on 1 November 200

Improving the sentence writing fluency of a student with attention deficit hyperactivity disorder and speech/language impairment: A pilot study

The skill of sentence writing – the composition of connected text into sentence types understandable to readers – is foundational to written expression. Unfortunately, many students with learning disabilities – particularly those with attention deficit hyperactivity disorder (ADHD) and speech and/or language impairment (S/LI) – struggle to develop sentence writing and its multiple, related skills. Using a single-baseline design, we studied effects of a supplemental writing intervention on one elementary-aged student with comorbid ADHD and S/LI. The intervention entailed delivery of a writing fluency intervention with several antecedent- and consequence-based components: explicit instruction, fluency practice, a reinforcer survey, and contingent reinforcement. The participating student improved his accuracy and speed of sentence writing during intervention. Results are discussed within the context of text writing fluency and frameworks of academic interventions for students with ADHD and S/LI

Equation of state for β\beta-stable hot nuclear matter

We provide an equation of state for hot nuclear matter in $\beta$-equilibrium by applying a momentum-dependent effective interaction. We focus on the study of the equation of state of high-density and high-temperature nuclear matter, containing leptons (electrons and muons) under the chemical equilibrium condition in which neutrinos have left the system. The conditions of charge neutrality and equilibrium under $\beta$-decay process lead first to the evaluation of proton and lepton fractions and afterwards of internal energy, free energy, pressure and in total to the equation of state of hot nuclear matter. Thermal effects on the properties and equation of state of nuclear matter are assesed and analyzed in the framework of the proposed effective interaction model. Special attention is dedicated to the study of the contribution of the components of $\beta$-stable nuclear matter to the entropy per particle, a quantity of great interest for the study of structure and collapse of supernova.Comment: 28 pages, 18 figure

Does the timing of breast cancer surgery in pre-menopausal women affect clinical outcome? : an update

There is some evidence that breast cancer surgery during the luteal phase in pre-menopausal women is associated with a better clinical outcome, however the evidence for this is still equivocal. In this paper, after summarizing the normal physiology of the menstrual cycle, we examine how such an association may occur and provide a comprehensive review of the literature in the area

The U.S. Law of Client Confidentiality: Framework for an International Perspective

In this Article, I will consider two general areas of the U.S. law of confidentiality. In Part I, I will reflect briefly upon what I call “the U.S. culture of lawyer-client confidentiality.” I say “culture” rather than “cult,” and one must guard against temptations to confuse those concepts. Those reflections will serve as background—by way of both match and contrast—to my sketch of the U.S. law of confidentiality in Part II

Pars plana vitrectomy for diabetic macular edema: a systematic review, meta-analysis, and synthesis of safety literature

Purpose. To assess the risk and benefit of pars plana vitrectomy for diabetic macular edema (DME). Methods. We conducted a systematic literature review using PubMed, EMBASE, Web of Science, and Cochrane Central Database of Controlled Trials until September 2014. The population was patients with DME, intervention vitrectomy, comparator macular laser or observation, and efficacy outcome visual acuity and central retinal thickness (CRT). Safety outcomes were intra- and postoperative surgical complications. The efficacy meta-analysis included only randomized controlled trials. The safety analysis included prospective, retrospective, controlled and uncontrolled studies. Results. Five studies were eligible for the efficacy meta-analysis (n = 127 eyes) and 40 for the safety analysis (n = 1,562 eyes). Combining follow up intervals from 6 to 12 months, the meta-analysis found a non-significant 2 letter visual acuity difference favoring vitrectomy, and a significant 102 micron greater reduction in CRT favoring vitrectomy, but a post-hoc subgroup analysis found that a 6 month CRT benefit reversed by 12 months. The most frequent complications were retinal break (7.1%), elevated intraocular pressure (5.2%), epiretinal membrane (3.3%), and vitreous hemorrhage (2.4%). Cataract developed in 68.6% of 121 phakic eyes. Conclusions. Vitrectomy produces structural and functional improvements in select eyes with DME, but the visual gains are not significantly better than with laser or observation. No major safety concerns were identified

Worldwide spreading of economic crisis

We model the spreading of a crisis by constructing a global economic network and applying the Susceptible-Infected-Recovered (SIR) epidemic model with a variable probability of infection. The probability of infection depends on the strength of economic relations between the pair of countries, and the strength of the target country. It is expected that a crisis which originates in a large country, such as the USA, has the potential to spread globally, like the recent crisis. Surprisingly we show that also countries with much lower GDP, such as Belgium, are able to initiate a global crisis. Using the {\it k}-shell decomposition method to quantify the spreading power (of a node), we obtain a measure of ``centrality'' as a spreader of each country in the economic network. We thus rank the different countries according to the shell they belong to, and find the 12 most central countries. These countries are the most likely to spread a crisis globally. Of these 12 only six are large economies, while the other six are medium/small ones, a result that could not have been otherwise anticipated. Furthermore, we use our model to predict the crisis spreading potential of countries belonging to different shells according to the crisis magnitude.Comment: 13 pages, 4 figures and Supplementary Materia

Towards Real-Time Control of a Semibatch Crystallization Process by Electrical and Ultrasound Tomographic Techniques

This research work presents a feasibility study to demonstrate the application of Electrical Resistance Tomography and transmission-based Ultrasound Computed Tomography for monitoring and control of micron-sized calcium carbonate crystallization process. Herein, precipitated calcium carbonate production is bind to a carbon dioxide absorption process based on hollow-fiber membrane contactor.ERT acquisition system is equipped with 16 electrodes with operating frequency of 156 KHz and image capturing frame rate of 2 Hz. The ultrasound tomography equipment consists of 32 piezoelectric transducers at a frequency of 200 KHz. These sensors are sensitive to changes in suspension density and conductivity. Furthermore, a process control framework is developed by utilizing the fundamental relations of settling velocity of particles. Through simulations in the LabVIEW software, the PI-based feedback controller demonstrates a possibility of setpoint tracking by manipulating the control variable (mixing speed). Upon further investigations, this approach can be used as a multi-dimensional process analytical technology tool for quality assurance and malfunction diagnosis when out-of-specification events occur throughout the entire process