1,739 research outputs found
National drought insurance for Malawi
Malawi has experienced several catastrophic droughts over the past few decades. The impact of these shocks has been far reaching, and the resulting macroeconomic instability has been a major constraint to growth and poverty reduction in Malawi. This paper describes a weather risk management tool that has been developed to help the government manage the financial impact of drought-related national maize production shortfalls. The instrument is an index-based weather derivative contract designed to transfer the financial risk of severe and catastrophic national drought that adversely impacts the government's budget to the international risk markets. Because rainfall and maize yields are highly correlated, changes in rainfall -- its timing, cumulative amount, and distribution -- can act as an accurate proxy for maize losses. An index has been constructed using rainfall data from 23 weather stations throughout Malawi and uses daily rainfall as an input to predict maize yields and therefore production throughout the country. The index picks up the well documented historical drought events in 2005, 1995, 1994, and 1992 and a weather derivative contract based on such an index would have triggered timely cash payouts to the government in those years. This innovative risk management instrument was pioneered in 2008/2009 by the Government of Malawi, with the assistance of the World Bank, and was a first for a sovereign entity in Africa. Several piloting seasons will be necessary to understand the scope and limitations of such contracts, and their role in the government's strategy, contingency planning, and operational drought response framework.Debt Markets,Hazard Risk Management,Banks&Banking Reform,Labor Policies,Insurance&Risk Mitigation
Correlative analysis of putative molecular predictive factors in patients with curatively resected stage III colon cancer, treated with adjuvant oxaliplatin-based chemotherapy.
Colon cancer is the second cause of death for neoplasm worldwide. In most cases it is diagnosed when still localized to the intestinal wall or in regional lymph nodes. Adjuvant therapy with 5-Fluorouracil (5FU) and folinic acid (FA), in combination with oxaliplatin (FOLFOX) are the standard options for patients with radically resected stage III disease. However, a proportion of patients will develop recurrence due to drug resistance and oxaliplatin-based chemotherapy is a regimen that may cause potentially disabling sensory neuropathy. Therefore there is an increase needing for a better selection of patients to be addressed to the most appropriate chemotherapeutic treatment, also in the adjuvant setting.
Several proteins and genetic markers have been described in an attempt to refine prognostic information and predict the benefit derived from systemic treatment. In particular TS protein expression, MSI, p53 expression, BRAF and TP53 mutations, have been described in several reports in relation to 5FU treatment, whereas ERCC1 polymorphism, ERCC1 expression and KRAS mutations, seem to be related to oxaliplatin efficacy in advanced colon cancer patients.
At this purpose we enrolled 230 patients from Argentina and Switzerland who underwent surgical resection, followed by 6-months adjuvant treatment: 106 were treated with 5FU alone and 124 with FOLFOX. In all the cases we investigated the MSI status by fragment analysis, we analyzed BRAF, KRAS, TP53 mutations and ERCC1 codon 118 polymorphism by direct sequencing and we performed ERCC1 expression analysis at protein and mRNA levels by immunohistochemistry and real-time PCR, respectively. Finally, we correlated the molecular and immunohistochemical results with the clinical data.
Above all, a little advantage in survival was observed for patients treated with FOLFOX regimen if compared to those treated with 5FU (51.3 and 41.6 months, respectively, for DFS; 55.4 and 49.3 months, respectively, for OS), although the difference was not statistically significant, probably due to the low number of analyzed cases.
We found MSI in 12% of cases, BRAF mutations in 9% of cases, KRAS mutations in 28% of cases and ERCC1 resulted over-expressed in 40% of cases detected by IHC and in 49% of cases detected by real-time PCR. These percentages, as well as the types of alterations, are in line with those published in the literature.
Concerning the correlations among markers, we observed a significant association between MSI and BRAF mutations (in agreement with the literature) and absence of association between KRAS mutations and ERCC1 expression (at odds with the hypothesis proposed in a recent preclinical study).
When we matched the clinical data of the whole patients cohort with molecular alterations, we found a trend towards a better prognosis for patients with MSI than for those with a MSS status (p=0.17); we observed that KRAS mutations confer a worse prognosis to advanced colon cancer patients, borderline for the DFS (p=0.07) and statistically significant for the OS (p=0.004); finally we found a trend towards a better DFS (p=0.11) for patients showing low levels of ERCC1 mRNA expression.
When we subdivided the patients on the basis of the received treatment (5FU versus oxaliplatin-based chemotherapy), we observed similar percentages of alterations of all the markers between the two groups. By correlating the molecular alterations with clinical data, we found a trend towards a better survival for MSI patients treated 5FU (p=0.16 and p=0.37 for DFS and OS, respectively), while for FOLFOX patients no clinical differences were found between MSI and MSS cases.
As for KRAS mutations, in 5FU group we observed a statistical significant worse DFS (p=0.04) and a trend towards a worse OS (p=0.07) in KRAS mutated patients if compared to wild-type patients. In FOLFOX group, no statistical differences were identified between KRAS mutated and wild-type cases. Stratifying the population on the basis of KRAS mutational status, we noticed that in wild-type patients there was no difference in the clinical outcome in the two treatment modalities. On the contrary, in mutated cases a trend towards a better DFS (p=0.28) and OS (p=0.20) was observed in FOLFOX treated patients if compared to 5FU group.
As regards ERCC1 expression, we found only a trend toward a better DFS (p=0.17) in patients characterized by low ERCC1 mRNA levels when treated with FOLFOX.
As for the last markers, ERCC1 codon 118 polymorphism (AAT/AAC) and TP53 mutations, we found percentages of alterations in line with the literature (for ERCC1 polymorphism: TT genotype in 31% of cases, CC genotype in 21% of patients; for TP53: 44% of cases showed at least one mutation). The correlations between these two markers and the clinical outcome are now under evaluation.
In conclusion, looking at the whole cohort, we can confirm a better clinical outcome for adjuvant colon cancer patients treated with FOLFOX regimen with respect to 5FU treatment. MSI could be a useful tool indicating a better prognosis also for advanced colon cancer but its role in predicting 5FU or FOLFOX efficacy remains controversial. In addition, we propose to assess ERCC1 mRNA expression analysis before the administration of oxaliplatin-based chemotherapy, in order to early identify the patients who may benefit the most from this treatment.
Finally, we suggest that KRAS mutational status could help clinicians in selecting the best chemotherapeutic treatment in the adjuvant setting: only KRAS mutant patients should be treated with a platinum-based chemotherapy, while patients whose tumour is KRAS wild-type can be treated with 5FU alone, thus preventing adverse side effect in a consistent number of cases. Our results, of course, deserve confirmations
Higher fuel and food prices: Economic impacts and responses for Mozambique
"Rising world prices for fuel and food represent a negative terms-of-trade shock for Mozambique. The impacts of these price increases are analyzed using various approaches. Detailed price data show that the world price increases are being transmitted to domestic prices. Short-run net benefit ratio analysis indicates that urban households and households in the southern region of the country are more vulnerable to food price increases. Rural households, particularly in the northern and central parts of Mozambique, often benefit because they sell more food goods than they consume (i.e., net seller). Long-term analysis using a computable general equilibrium model of Mozambique indicates that the fuel price shock dominates rising food prices from both macroeconomic and poverty perspectives. Here again, negative impacts are greater in urban areas than in rural areas. The importance of agricultural production response in general, and export response in particular, are highlighted in this discussion. Policy analysis reveals difficult trade-offs between short-run mitigation and long-run growth. Improved agricultural productivity has powerful positive impacts, but remains difficult to achieve and may not address the immediate impacts of higher prices. " from authors' abstractPrice transmission, Terms-of-trade shocks, food security, Food prices, Development strategies,
Finite Element Methods against Limit Equilibrium Approaches for Slope Stability Analysis
A number of powerful numerical models, including limit equilibrium and finite element (FE) methods, have been developed for slope stability analysis in recent decades. The limit equilibrium method contains several limitations, yet is considered the most common approach. However, the advancement of technology has increased the use of the finite element method as it embraces a wider range of features. The limit equilibrium software, SLOPE/W, and the FE program PLAXIS are two common software programs currently employed in geotechnical engineering. Slope analysis using the limit equilibrium method involves a series of slip surfaces dividing ground into vertical slices, and using the static equilibrium equations to calculate the factor of safety (FOS) and stresses for each slice. PLAXIS requires the input of soil properties and elastic-plastic parameters of elements. In this study the properties of a heterogeneous slope, consisting of general fill embankment over soft, slightly overconsolidated clay is implemented in each program. The FOS of slopes is determined for subsequent design requirements, and results are analysed and comparisons are conducted. The effect of Youngâs modulus on the FOS is also discussed. Recommendations are provided based on the results and previously published findings. The contribution of this paper is beneficial to geotechnical engineers, as it discusses the suitability and limitations of each method and assesses reliability of model outputs for slope stability analyses
Clinical applications of non-invasive imaging techniques in suspected coronary artery disease and in acute myocardial infarction
Non-invasive cardiac imaging modalities play a crucial role in the diagnostic process and clinical management of patients without known coronary artery disease and patients with acute myocardial infarction. The first part of the thesis discusses the use of non-invasive imaging modalities (including coronary artery calcium scoring, multi-slice computed tomography coronary angiography, conventional two-dimensional echocardiography and speckle-tracking echocardiography) for the diagnosis and risk stratification of patients with suspected coronary artery disease. The second part of the thesis discusses the diagnostic and prognostic value of novel echocardiographic techniques (including contrast echocardiography, myocardial deformation imaging, and three-dimensional echocardiography) in patients admitted with acute myocardial infarction.UBL - phd migration 201
Averting HIV Infections in New York City: A Modeling Approach Estimating the Future Impact of Additional Behavioral and Biomedical HIV Prevention Strategies
Background:New York City (NYC) remains an epicenter of the HIV epidemic in the United States. Given the variety of evidence-based HIV prevention strategies available and the significant resources required to implement each of them, comparative studies are needed to identify how to maximize the number of HIV cases prevented most economically.Methods:A new model of HIV disease transmission was developed integrating information from a previously validated micro-simulation HIV disease progression model. Specification and parameterization of the model and its inputs, including the intervention portfolio, intervention effects and costs were conducted through a collaborative process between the academic modeling team and the NYC Department of Health and Mental Hygiene. The model projects the impact of different prevention strategies, or portfolios of prevention strategies, on the HIV epidemic in NYC.Results:Ten unique interventions were able to provide a prevention benefit at an annual program cost of less than 106,378; the total cost was in excess of 100 million per year, on average). The cost-savings of prevented infections was estimated at more than 250 million per year, on average).Conclusions:Optimal implementation of a portfolio of evidence-based interventions can have a substantial, favorable impact on the ongoing HIV epidemic in NYC and provide future cost-saving despite significant initial costs. © 2013 Kessler et al
ARMOURED SCALE INSECTS (HEMIPTERA: COCCOIDEA: DIASPIDIDAE) NEW TO SICILY: RECORDS AND OBSERVATIONS
ARMOURED SCALE INSECTS (HEMIPTERA: COCCOIDEA: DIASPIDIDAE) NEW TO SICILY: RECORDS AND OBSERVATIONS. The central location of Sicily in the Mediterranean basin makes studies of its fauna particularly interesting. Recent collections from the scrub vegetation on the South-East coast of Sicily and the slopes of Mount Etna have produced four new records of Diaspididae for Sicily: Aonidia ?mediterranea (Lindinger), Ferreroaspis hungarica (Vinis), Mercetaspis isis (Hall) and Chionaspis etrusca Leonardi. The presence of the first three species suggests old faunistic links with other regions, mainly eastern Mediterranean. Our findings are presented here in the hope of stimulating more such research. Key words: Callitris, Cupressus, Juniperus, Thuja, Tamarix, Acer, Cerasus, Carulaspis silvestrii, C. minima, C. juniperi, ecology, host reaction
INSECTS AND FUNGI ON THE RELICT ZELKOVA SICULA(ROSALES, ULMACEAE)IN SICILY (ITALY): NEW RECORDS AND KNOWN SPECIES IN A SHORT REVIEW
The Authors report the results of a study conducted with the purpose of increasing the knowledge about theinsects and fungi living on Zelkova siculaDi Pasquale, Garfì & Quézel, 1992 (Rosales, Ulmaceae). The plant is a veryrare relict of the Tertiary period, belonging to a genus of trees extinct in continental Europe. Only two small populationsare known living in a restricted woodland in the province of Syracuse, Sicily. The results concern both the insectspicked up during surveys that were carried out in 2014 and 2015, and the species of fungi and insects already known onZelkova siculafrom literature. As a result of surveys, two species of Buprestidae, two species of Cerambycidae, andtwo of Lepidoptera have been recognized. From literature, seven species of phytophagous insects are reported onZelkova sicula, they belong to Hemiptera: Aphididae (1 sp.), Diaspididae (1 sp.), Coccidae (1 sp.); Coleoptera:Buprestidae (1 sp.), Cerambycidae (2 spp.); and Lepidoptera: Lasiocampidae (1 sp.). Five species of fungi are knownfrom literature and they belong to: Botryosphaeriales (3 spp.), Pleosporales (1 sp.), and Diaporthales (1 sp.)
Should expectations about the rate of new antiretroviral drug development impact the timing of HIV treatment initiation and expectations about treatment benefits?
Background: Many analyses of HIV treatment decisions assume a fixed formulary of HIV drugs. However, new drugs are approved nearly twice a year, and the rate of availability of new drugs may affect treatment decisions, particularly when to initiate antiretroviral therapy (ART). Objectives: To determine the impact of considering the availability of new drugs on the optimal initiation criteria for ART and outcomes in patients with HIV/AIDS. Methods: We enhanced a previously described simulation model of the optimal time to initiate ART to incorporate the rate of availability of new antiviral drugs. We assumed that the future rate of availability of new drugs would be similar to the past rate of availability of new drugs, and we estimated the past rate by fitting a statistical model to actual HIV drug approval data from 1982-2010. We then tested whether or not the future availability of new drugs affected the model-predicted optimal time to initiate ART based on clinical outcomes, considering treatment initiation thresholds of 200, 350, and 500 cells/mm 3. We also quantified the impact of the future availability of new drugs on life expectancy (LE) and quality-adjusted life expectancy (QALE). Results: In base case analysis, considering the availability of new drugs raised the optimal starting CD4 threshold for most patients to 500 cells/mm 3. The predicted gains in outcomes due to availability of pipeline drugs were generally small (less than 1%), but for young patients with a high viral load could add as much as a 4.9% (1.73 years) increase in LE and a 8% (2.43 QALY) increase in QALE, because these patients were particularly likely to exhaust currently available ART regimens before they died. In sensitivity analysis, increasing the rate of availability of new drugs did not substantially alter the results. Lowering the toxicity of future ART drugs had greater potential to increase benefit for many patient groups, increasing QALE by as much as 10%. Conclusions: The future availability of new ART drugs without lower toxicity raises optimal treatment initiation for most patients, and improves clinical outcomes, especially for younger patients with higher viral loads. Reductions in toxicity of future ART drugs could impact optimal treatment initiation and improve clinical outcomes for all HIV patients. © 2014 Khademi et al
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