Identification of phytotoxins from Botryosphaeria obtusa , a pathogen of black dead arm disease of grapevine

A bioassay-guided fractionation of a culture filtrate of Botryosphaeria obtusa led to the isolation of four dihydroisocoumarins, named mellein 1, 4-hydroxymellein 2, 7-hydroxymellein 3 and the new 4,7-dihydroxymellein 4. LC-UV-DAD-MS analysis of vine wood infected by B. obtusa revealed the presence of mellein (1). Botryosphaeria obtusa was also able to oxidise wood δ -resveratrol into the dimer delta-viniferin. The structures of isolated phytotoxins were established on the basis of IR, MS, 1D and 2D NM

Consumption of Alcoholic Beverages among Adolescents in Kinshasa: Diagnosis and Therapy

The study analyzed the age of onset of alcohol consumption among adolescents in Kinshasa The study led to the following results 44 2 of adolescents in the cityprovince of Kinshasa start consuming alcohol at the age of 16- 17 These teenagers use alcohol to solve a disturbing problem 33 3 The following factors promote alcohol consumption parents p 0 432 r 0 000 friends p 0 418 r 0 000 culture p 0 627 r 0 000 social classes p 0 639 r 0 000 family heredity p 0 401 r 0 000 school p 0 361 r 0 000 availability and publicity p 0 349 r 0 000 and alcohol consumption by adolescent

Verification of the Energy Balance of a Passive House by Combining Measurements and Dynamic Simulation

AbstractPassive houses have, at design stage, to fulfill a number of performance criteria. One of them imposes the normalized theoretical heat demand to be limited to 15 kWh/m2, year. In operation, it is very difficult to check, from simple observations or measurements, the real performance of such a house: different energy vectors may be used to meet the space heating as well as the domestic hot water demand, a storage tank may be used and fed by different energy sources (heat pump, direct electricity, solar thermal). The problem is still more complicated if the house is equipped with PV panels which naturally decrease the apparent electrical consumption. In the frame of the IEA Annex 58 project, a passive house was the object of a detailed analysis aiming at estimating the different terms of the energy balance. Some terms were results of direct in situ measurements and unmeasured terms such as solar and internal gains were estimated by dynamic simulation. The combination of measurements and simulation results allowed a reconstruction of a robust energy balance. The paper provides a detailed description of the approach and of each term of the rebuilt energy balance

Investigating the impact of atmospheric boundary layer stratification on wind farm noise propagation

The expansion of wind farm installations has been hindered by annoyance issues resulting from the noise emitted by wind turbines. Understanding the factors that affect sound propagation is crucial to mitigate the impact of noise. Atmospheric boundary layer (ABL) stratification strongly affects the noise propagation of isolated wind turbines. However, few studies have looked at the influence of atmospheric conditions on wind farm noise propagation. This study aims to investigate this through numerical simulations. Large eddy simulations (LES) are used to predict the mean flow inside and around the wind farm. The noise from each wind turbine is computed from an extended source model that determines the wind turbine sound production based on its geometry, and on the flow characteristics (wind speed and turbulence intensity). A model based on the parabolic equation is employed to compute the sound propagation based on the flow fields obtained from LES. Neutral, stable and unstable stability conditions are considered for an idealized wind farm layout. The results of this study provide insight into the influence of atmospheric conditions on wind farm sound propagation and can inform the development of effective noise mitigation strategies.</p

Manon

De cada obra s'ha digitalitzat un programa sencer. De la resta s'han digitalitzat les parts que són diferents.Empresa Juan A. PamiasÒpera de Jules Massenet i llibret de Meilhac i Gill