Reintroduction of native cotton (Gossypium Barbadian) on the North coast of Peru: analysis of economic feasibility for small producers

In Peru the agro-export boom has determined a major shift of large farmers from traditional agro-industrial crops (coffee and cotton) to new agribusinesses (asparagus, oranges, avocados, apples). These dynamics have left room for the small farmers to enter the traditional agro-industrial sector, or into new niche markets as in the case of native cotton. On the North coast of Peru the cultivation of the native and naturally coloured cotton (Gossypium Barbadense spp. locally called algod\uf3n El Pa\ueds) is part of the Moche indigenous culture (a local pre-Inca population). Since 1949 the Peruvian legal prohibition to produce native cotton, linked to the risk of genetic contamination of the industrial white cotton cultivations, made the keeping of these traditional varieties very difficult. Nevertheless the situation has totally changed since 2008 due to Regulation n\ub0 29224 declaring native cotton as a genetic, ethnic and cultural heritage of the country. This study analyses the economic feasibility of re-inserting the native cotton as part of the agricultural production of 50 farmers on the North coast of Peru, proposing a farm economic data analysis, scenario analysis and sensitivity analysis based on OFAT (One Factor at A Time) methodology: the results attest that in all the productive scenarios proposed (10%, 25% and 50% of the farm agricultural surface growing native cotton) the average farm incomes are going to increase. Moreover the sensitivity analysis attests that also in the worst conditions of a 10% decrease in the native cotton price, the average farm incomes with native cotton are higher compared to the business as usual scenario in all three productive scenarios proposed

Shortening of the Short Refractory Periods in Short QT Syndrome.

BACKGROUND: Diagnosis of short QT syndrome (SQTS) remains difficult in case of borderline QT values as often found in normal populations. Whether some shortening of refractory periods (RP) may help in differentiating SQTS from normal subjects is unknown. METHODS AND RESULTS: Atrial and right ventricular RP at the apex and right ventricular outflow tract as determined during standard electrophysiological study were compared between 16 SQTS patients (QTc 324±24 ms) and 15 controls with similar clinical characteristics (QTc 417±32 ms). Atrial RP were significantly shorter in SQTS compared with controls at 600- and 500-ms basic cycle lengths. Baseline ventricular RP were significantly shorter in SQTS patients than in controls, both at the apex and right ventricular outflow tract and for any cycle length. Differences remained significant for RP of any subsequent extrastimulus at any cycle length and any pacing site. A cut-off value of baseline RP <200 ms at the right ventricular outflow tract either at 600- or 500-ms cycle length had a sensitivity of 86% and a specificity of 100% for the diagnosis of SQTS. CONCLUSIONS: Patients with SQTS have shorter ventricular RP than controls, both at baseline during various cycle lengths and after premature extrastimuli. A cut-off value of 200 ms at the right ventricular outflow tract during 600- and 500-ms basic cycle length may help in detecting true SQTS from normal subjects with borderline QT values

Etiological diagnosis, prognostic significance and role of electrophysiological study in patients with Brugada ECG and syncope.

BACKGROUND: Syncope is considered a risk factor for life-threatening arrhythmias in Brugada patients. Distinguishing a benign syncope from one due to ventricular arrhythmias is often difficult, unless an ECG is recorded during the episode. Aim of the study was to analyze the characteristics of syncopal episodes in a large population of Brugada patients and evaluate the role of electrophysiological study (EPS) and the prognosis in the different subgroups. METHODS AND RESULTS: One hundred ninety-five Brugada patients with history of syncope were considered. Syncope were classified as neurally mediated (group 1, 61%) or unexplained (group 2, 39%) on the basis of personal and family history, clinical features, triggers, situations, associated signs, concomitant therapy. Most patients underwent EPS; they received ICD or implantable loop-recorder on the basis of the result of investigations and physician's judgment. At 62±45months of mean follow-up, group 1 showed a significantly lower incidence of arrhythmic events (2%) as compared to group 2 (9%, p<0.001). Group 2 patients with positive EPS showed the highest risk of arrhythmic events (27%). No ventricular events occurred in subjects with negative EPS. CONCLUSION: Etiological definition of syncope in Brugada patients is important, as it allows identifying two groups with different outcome. Patients with unexplained syncope and ventricular fibrillation induced at EPS have the highest risk of arrhythmic events. Patients presenting with neurally mediated syncope showed a prognosis similar to that of the asymptomatic and the role of EPS in this group is unproven

Electronic structure of fluorides: general trends for ground and excited state properties

The electronic structure of fluorite crystals are studied by means of density functional theory within the local density approximation for the exchange correlation energy. The ground-state electronic properties, which have been calculated for the cubic structures $CaF_{2}$,$SrF_{2}$, $BaF_{2}$, $CdF_{2}$, $HgF_{2}$, $\beta$-$PbF_{2}$, using a plane waves expansion of the wave functions, show good comparison with existing experimental data and previous theoretical results. The electronic density of states at the gap region for all the compounds and their energy-band structure have been calculated and compared with the existing data in the literature. General trends for the ground-state parameters, the electronic energy-bands and transition energies for all the fluorides considered are given and discussed in details. Moreover, for the first time results for $HgF_{2}$ have been presented

Multipole expansions of the electrostatic molecular potential

Multipole expansions of the electrostatic molecular potential up to the hexadecapole terms are examined for H20, NH 3 and C2H~NH. A reasonable approximation to get unexpensive first order representations of the electrostatic potential for regions outside the van der Waals volume is found