The Impact of Real Exchange Rate Misalignment and Instability on Macroeconomic Performance in Sub-Saharan Africa

This study investigates the relationship between indicators of macroeconomic performance and real exchange rate (RER) misalignment and instability in Sub-Saharan Africa (SSA). Three measures of RER misalignment are used. There is ample evidence that countries which have pursued more predictable macroeconomic policies and lower levels of RER misalignment have experienced better economic performance. Also, it appears that higher levels of misalignments in the RER are accompanied by higher levels of macroeconomic instability. Empirical support is found for Edwards' model of the equilibrium RER and black market premia tend to show a greater degree of misalignment than alternative measures.Financial Economics, International Relations/Trade,

Gas dispersion and bubble-to-emulsion phase mass exchange in a gas-solid bubbling fluidized bed: a computational and experimental study

Knowledge of gas dispersion and mass exchange between the bubble and the emulsion phases is essential for a correct prediction of the performance of fluidized beds, particularly when catalytic reactions take place. Test cases of single rising bubble and a bubbling fluidized bed operated with a jet without a chemical reaction were studied in order to obtain fundamental insights in the prevailing mass transfer phenomena. Numerical simulations were carried out to predict the dispersion of tracer gas using a two-fluid model based on Kinetic Theory of Granular Flow (KTGF). The simulations of a single-bubble rising through an incipiently fluidized bed revealed that the assumptions often made in phenomenological models in the derivation of correlations for the mass transfer coefficient, mainly that the bubble diameter remains constant and that the tracer concentration is uniform in the bubble, are not valid. The predicted bubble-to-emulsion phase mass transfer coefficient showed good agreement with the estimated values from the literature correlations assuming additive convection-diffusion transport for different bubble sizes and different particle sizes, indicating the importance of the convective distribution even for relatively small particles. Experiments were carried out to measure the steady state concentration profiles of a tracer gas in a pseudo two-dimensional bubbling fluidized bed operated with a jet. The simulated steady state concentration profiles of the tracer gas agreed well the experimental measurements. The radial convection of the gas is significantly influenced by the bubble `throughflow¿ and therefore depends upon the particle and bubble size. The experimental comparison of theoretical results was extended to study the influence of the jet velocity and the particle diameter on the radial dispersion of the tracer gas in the bed

MANCOZEB EXPOSURE RESULTS IN OXIDATIVE STRESS AND DISRUPTION OF MITOCHONDRIAL COMPLEXES III & IV IN TRANSFORMED HUMAN COLON CELLS

The ethylene bisdithiocarbamate pesticides, a subclass of the dithiocarbamate pesticides, are broad spectrum organometallic fungicides used on a variety of crops. The fungicide Mancozeb is comprised of an ethylene bisdithiocarbamate backbone complexed to the metals manganese and zinc. Ingestion of food containing pesticide residue and occupational exposure are common routes of Mancozeb exposure. Previous work demonstrated that Mancozeb exposure to HT-29 colon cancer cells resulted in cytotoxicity, apoptosis, and disruption of mitochondrial complex I, II, and V activity. The current study investigated the effect of Mancozeb exposure on mitochondrial complex III and IV activity and oxidative stress parameters in the HT-29 cell line. Kinetic assays were used to evaluate and compare the effect of Mancozeb exposure on the activity of complexes III and IV. Complex III showed a significant decrease in activity at 60 µM and 100 µM Mancozeb. Activity of complex IV showed significant decreases at 60 µM, 100 µM, and 140 µM Mancozeb. Further mitochondrial disruption was seen in transmission electron micrographs that showed severe mitochondrial distortions at 100 µM Mancozeb. Significant loss of mitochondrial membrane potential (60 µM, 100 µM, and 140 µM Mancozeb) measured with use of a fluorescent mitochondrial potential dye, further confirmed mitochondrial disruption and induction of apoptosis. Scanning electron micrographs demonstrated cellular blebbing at concentrations of 80-140 µM Mancozeb. Quantification of cell blebbing from SEM micrographs revealed a significant increase in the mean percentage of blebbed cells at 100 µM Mancozeb. Oxidative stress parameters were measured to determine the role in mitochondrial dysfunction following Mancozeb exposure. Cellular reactive oxygen species, mitochondrial superoxide, and superoxide dismutase 2 levels were all significantly increased at concentrations of 100 µM and 140 µM Mancozeb. The antioxidant capacity of the cells was significantly decreased at 100 µM and 140 µM Mancozeb. Antioxidant pre-treatment and co-treatment with butylated hydroxy toluene and MitoQ failed to increase cell viability of cells exposed to 100 µM Mancozeb. The results indicate that the underlying mechanism of Mancozeb toxicity that contributes to mitochondrial dysfunction is oxidative stress in HT-29 cells

World Bank adjustment lending and economic performance in sub-Saharan Africa in the 1980s : a comparison with other low income countries

The authors investigated the factors that influenced the participation of sub - Saharan African countries and all low-income countries in World Bank adjustment lending. They estimated how the Bank's adjustment programs affected economic performance in both regions. They found that the marginal contribution of Bank-supported adjustment programs to export performance has been postive and significant in sub - Saharan Africa, given the potentially important links between export growth and economic growth. But adjustment programs have not significantly affected economic growth in sub - Saharan Africa and have had a deleterious effect on investment there. This strengthens theargument of those who call for more explicit consideration of the initial conditions of the sub - Saharan African economies in the design, emphasis, and schedule of their adjustment programs. For one thing, a redefined but more important role for governments is in order for reforming African economies. Fiscal and monetary retrenchment are still indispensable, but it is critical that there be more public investment in infrastructure, human capital, and agricultural technology - to generate a supply response. Moreover, efforts must be made to make policy reforms more credible to the private sector and to improve program implementation. Also, governance and political stability - politically sensitive issues - critically affect the adoption, implementation, sustainability, and credibility of adjustment programs.Country Strategy&Performance,Economic Theory&Research,Achieving Shared Growth,Environmental Economics&Policies,Inequality

How commodity prices respond to macroeconomic news

This paper analyzes the immediate, delayed and group responses of 20 commodity prices in four commodity groups (foods and livestock, crops, energy and metals) to macroeconomic"news"(unexpected announcements) in the United States between 1985 and 1989. It finds that macroeconomic news generally affects commodities within groups in the same direction - but there is no clear evidence that the prices of largely unrelated commodity groups react in the same way to macroeconomic shocks. The paper also notes that the business cycle must be carefully considered in analyzing the impact of macroeconomic news on commodity prices. It looks at variables such as inflation, exchange rates, interest rates, money stock and real activity. For each of the variables, the immediate impact of news is often different from the one-day-lagged impact - and different for different commodity groups.Economic Theory&Research,Environmental Economics&Policies,Markets and Market Access,Access to Markets,Insurance&Risk Mitigation

Cotton sector strategies in West and Central Africa

Cotton production is truly a success story in West and Central Africa. The region is now the second largest exporter of lint, after the United States, with a world market share of 15 percent. Despite its strong performance in the past, the sector is characterized by several institutional and structural weaknesses that jeopardize its viability in an era of increasing globalization of the cotton industry. The sector's future performance will also depend on the implications of cotton sector policies in major producing countries such as the United States, the European Union, and China. This paper examines how the above factors may affect future growth of the region's cotton industry. It also identifies the changes that are required to enable countries in the region to fully exploit the sector's significant growth potential.Environmental Economics&Policies,Agricultural Research,Markets and Market Access,Economic Theory&Research,Crops&Crop Management Systems,Markets and Market Access,Crops&Crop Management Systems,Environmental Economics&Policies,Economic Theory&Research,Agricultural Research

AN UPDATE ON PHARMACOLOGICAL PROFILE OF BOSWELLIA SERRATA

Boswellia serrata (Burseraceae) is the most ancient and respected herbs in Ayurveda. In Unani system of medicine, oleo-gum resin of Boswellia serrata named Kundur played a prime ingredient role in modern quality perfumes. The gum is used as a remedy for treatment of illness especially skin diseases and rheumatism in Indian system of medicine (Sidha, Ayurvedic and Unani) for last diverse centuries. Salai guggul is one of the accepted drugs for various complaints such as dyspepsia, dysentery, lung diseases, urinary disorder, haemorrhoids and corneal ulcer in Unani system of medicine for the last several decades.The present article is aimed to provide an overview on various pharmacological activities of Boswellia serrata. The resin fraction of salai guggal is rich in boswellic acids and its essential oils that are composed of a mixture of mono, di and sesquiterpenes while gum fraction chiefly contains pentose and hexose sugars. The oleo-gum resin is quite popular among the practitioners of traditional system and possesses wide range of useful biological properties such as antiasthmatic, anticancer, antifungal, anticomplementary, antihyperlipidemic, antiinflammatory, antiarthritic, antirheumatic, antidiarrheal, antimicrobial, antifungal and analgesic.An exhaustive review of literature was performed using various databases on science direct, scopus, pubmed, google scholar and free patents online.This review is a sincere attempt to discuss and present the current status of pharmacological profile of Boswellia serrata

Development and validation of a stability-indicating lc method for the determination of tenofovir disoproxil fumarate in pharmaceutical formulation

The present study describes the degradation of tenoforvir disoproxil fumarate (teno) under different prescribed stressconditions (hydrolysis, oxidation, dry and wet heat and photolysis) following the International Conference on Harmonization and application of a specific and selective stability-indicating reversed-phase high–performance liquid chromatography(HPLC) assay. Separation of drug and degradation products was successfully achieved on C18 analytical column usingmethanol: water (60:40, v/v) at a flow rate of 1.0 ml/min and detection at 260 nm, the mass balance was found to be close to100.4%. The developed HPLC method was validated with respect to linearity, accuracy, precision, robustness, and accuracy

Stress Studies of Tenofovir Disoproxil Fumarate by HPTLC in Bulk Drug and Pharmaceutical Formulation

A stability-indicating high-performance thin-layer chromatographic (HPTLC) method for determination of tenofovir disoproxil fumarate in bulk drug and in tablet has been developed and validated. The mobile phase selected was chloroform : methanol (9.0 : 1.0, v/v) with ultraviolet (UV) detection at 260 nm. The retention factor was found to be 0.49 ± 0.03 with correlation coefficients of 0.9994 in the range 300–1500 ng/spot and with an accuracy of 99.25%. Method had the potential to determine tenofovir disoproxil fumarate from tablet without any interference, and it was a stability-indicating one

A Posynomial Geometric Programming Restricted to a System of Fuzzy Relation Equations

AbstractA posynomial geometric optimization problem subjected to a system of max-min fuzzy relational equations (FRE) constraints is considered. The complete solution set of FRE is characterized by unique maximal solution and finite number of minimal solutions. A two stage procedure has been suggested to compute the optimal solution for the problem. Firstly all the minimal solutions of fuzzy relation equations are determined. Then a domain specific evolutionary algorithm (EA) is designed to solve the optimization problems obtained after considering the individual sub-feasible region formed with the help of unique maximum solution and each of the minimal solutions separately as the feasible domain with same objective function. A single optimal solution for the problem is determined after solving these optimization problems. The whole procedure is illustrated with a numerical example