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The quantification of evapotranspiration from irrigated areas is important for agriculture water management, especially in arid and semi-arid regions where water deficiency is becoming a major constraint in economic welfare and sustainable development. Conventional methods that use point measurements to estimate evapotranspiration are representative only of local areas and cannot be extended to large areas because of landscape heterogeneity. Remote sensing-based energy balance models are presently most suited for estimating evapotranspiration at both field and regional scales. In this study, we aim to develop a methodology based on the triangle concept, allowing estimation of evapotranspiration through the classical equation of Priestley and Taylor (1972) where the proportional coefficient α in this equation is ranged using a linear interpolation between surface temperature and Normalized Difference Vegetation Index (NDVI) values. Preliminary results using remotely sensed data sets from Landsat ETM+ over the Habra Plains in west Algeria are in good agreement with ground measurements. The proposed approach appears to be more reliable and easily applicable for operational estimation of evapotranspiration over large areas.

This study aims to highlight the utilization of literary genre as a well-liked method for instructing both language skills (that is to say, writing, reading, speaking, and listening) and language fields (that are grammar, pronunciation, and vocabulary). Why employing literary textbooks in foreign language classrooms and the main motives for choosing appropriate fictional texts in these classrooms are emphasized to make the reader acquainted with the motivating incentives and standards for foreign language teachers' employing and picking erudite textbooks. Additionally, the teaching of language skills and literary genre gains benefits of diverse fields of literature (like drama, poems, tragedy and tales) to language teaching and to several difficulties met by language teachers in the sphere of instructing English using fiction (i.e. shortage of training in the field of literature teaching English as a Second English and Teaching English as a Foreign Language curriculums, deficiency of precise aims describing the function of fiction in English as a Foreign Language and English as a Second Language, foreign language teachers' not possessing the experience and preparation in literature, and lack of suitable teaching tools to be utilized by foreign language teachers in a class milieu) are taken into consideration.

The drainage basin of Isser, space weakened by the periods of drought and characterized by exposures of marls and very fragile clays, prese nts a high sensitivity to erosion. In addition to the deterioration of the quality of water, the eros ion phenomenon in this zone presents risks of depletion of topsoil, loss of fertility, loosening of plants and pollution by pesticides dissolved in surface water runoff. The erosion results from the conjunction of many pe rmanent factors (as those related to the soil or to the topography), that are evolving o r presenting a random character (such as precipitations) and intervene at different levels i n erosion processes. The purpose of the work is to produce a map of soil vulnerability to the erosion by integrating field data, different thematic maps and satellite images through GIS solution. This map sho uld be a basis for the development of the anti-eros ive land use plan adapted to the specific context of th e drainage basin of Isser. We do integrate four factors which determine the erosion: precipitations , topography, lithology, and vegetation cover. For combining these different factors, we use a cut ting space in regular meshes. The resulting map of the vulnerability to the erosion should reveal homo geneous areas for priority interventions.

The trimeric heptad repeat domains HR1 and HR2 of the human immunodeficiency virus 1 (HIV-1) gp41 play a key role in HIV-1-entry by membrane fusion. To develop efficient inhibitors against this step, the corresponding trimeric-N36 and C34 peptides were designed and synthesized. Analysis by circular dichroism of monomeric and trimeric N36 and C34 peptides showed their capacities to adopt α-helical structures and to establish physical interactions. At the virological level, while trimeric-C34 conserves the same high anti-fusion activity as monomeric-C34, trimerization of N36-peptide induced a significant increase, reaching 500-times higher in anti-fusion activity, against R5-tropic virus-mediated fusion. This result was associated with increased stability of the N36 trimer peptide with respect to the monomeric form, as demonstrated by the comparative kinetics of their antiviral activities during 6-day incubation in a physiological medium. Collectively, our findings demonstrate that while the trimerization of C34 peptide had no beneficial effect on its stability and antiviral activity, the trimerization of N36 peptide strengthened both stability and antiviral activity. This approach, promotes trimers as new promising HIV-1 inhibitors and point to future development aimed toward innovative peptide fusion inhibitors, microbicides or as immunogens.

Abstract The bacteriocidal properties of silver nanoparticles (AgNPs) depend on their average diameter (toxicity increases with decreasing diameter). In the present work, we describe novel green chemistry biosynthesis of AgNPs from AgNO3 added to cell-free culture medium of baker’s yeast, Saccharomyces cerevisiae, yielding nanoparticles in the range 11–25 nm. However, when yeast was grown in a moderate static magnetic field, AgNPs obtained from the resulting cell-free culture medium, were significantly smaller (2–12 nm) than those obtained without magnetic field. These latter nanoparticles were highly crystalline, stable and near-uniform shape. Furthermore, the antibacterial activity of AgNPs obtained from static magnetic fields were greater than those from control cultures. Static magnetic fields show a promising ability to generate biocidal nanoparticles via this novel green chemistry approach.

Abstract Accurate spatio-temporal estimation of evapotranspiration (ET) and surface energy fluxes is crucial for many agro-environmental applications, including the determination of water balance, irrigation scheduling, agro-ecological zoning, simulation of global changes in land use and forecasting crop yields. Remote sensing based energy balance models are presently most suitable for estimating ET at both temporal and spatial scales. This study presents an intercomparison of ET maps over the Habra plain in western Algeria obtained with two different models: Ts/VI trapezoid (Surface temperature/Vegetation Index Trapezoid Model) and SEBAL (Surface Energy Balance Algorithm for Land). Ts/VI trapezoid is the most used model, due to its simplicity, ease of use, few data input requirements and relatively high accuracy. It allows estimating ET directly by using the Priestley-Taylor equation. Whereas SEBAL allows estimating ET as the residual term of the energy balance equation, by using a rather complex hot and cold pixel based contextual approach to internally calibrate sensible heat flux through an iterative approach. The data set consists of four Landsat-8 OLI/TIRS images acquired on 2018-2019 and some ground measurements. In conclusion, the results show that SEBAL and Ts/VI trapezoid models provide comparable outputs and suggest that both the two models are suitable approaches for ET mapping over agricultural areas where ground measurements are scarce or difficult to collect.

The present study aims to work out a methodology based on the use of the sensors such TERRA MODIS (MODerate resolution Imaging Spectroradiometer) in the desertification following and the detection of desertification risk zones in the northern area of Algeria. To this end, some geophysical parameters (albedo "R0", vegetation index "NDVI'' and surface temperature "TS") are produced regularly and cover the period of 2000 to 2005. The combination of these parameters two per two especially R0 -TS, NDVI-TS and R0 - NDVI has allowed respectively the characterization of the hydric and vegetation state. The synthesis of the totality of results under a geographical information system GIS as well as their confrontation with others types of data have allowed to map the desertification risk following five degrees (very high, high, moderated, weak and stable). Our results show that 75 % of the risk zones are already desertify or near of desertification.

O objetivo do presente estudo é o de estimar a erosividade da chuva na bacia hidrográfica de Macta, no oeste da Argélia. Usou-se o mapeamento por SIG (sistema de informações geográficas) para permitir uma melhor visualização da erosividade. Foram testados cinco índices de erosividade, i.e., índice de Arnoldus, índice de Fournier modificado por Arnoldus (MFI), índice de Rango-Arnoldus, índice de Leprun e índice de Val et al., para uma série de chuvas, registadasem 42 estações, durante um período de 41 anos. A precipitação a variar entre 300 e 400 mm ocorre na maior parte das estações, mais precisamente em 24 (57% da bacia) e os respectivos valores de erosividade de Arnoldus, MFI e erosividade de Rango-Arnoldus oscilam entre 86,54 e 123,93 MJMw/ha.ano , 47,47 e 75,33 e 16,11 a 36,13, respetivamente. A variabilidade mensal da precipitação tem um papel importante na concentração da erosividade. Na bacia hidrográfica, os valores de erosão (MFI) variaram entre 19,22 e 126,78, o que lhe confere um baixo potencial erosivo. Precipitaçõesinferiores a 300 mm, registadas em 15 estações pluviométricas (36%), possuem valores de erosividade que variam,respetivamente, de 39,78MJMw/ha.ano, 19,22 e 3,34 a 109,73MJ Mw/ha.ano, 50,27 e 17,80. O índice de erosividade depende não apenas da precipitação anual, mas também do regime intra-anual da precipitação. Assim, a razão índice MFI/índice Rango-Arnoldus R, estará mais próxima da unidade quando a precipitação aumenta e quanto mais a chuva diminuir, mais a proporção aumenta em favor do índice MFI. Os índices são muito próximos quando a precipitação anual atinge ou excede 500 mm. Este estudo mostrou o interesse da variabilidade interanual e a sua influência na erosividade pluvial. O mesmo índice de erosividade pode ter valores diferentes, para a mesma quantidade anual de precipitação, pois é a variabilidade interanual da precipitação que induz um alto índice de erosividade. O método de cálculo da erosividade descrito por Paez mostrou-se eficaz, permitindo superar a restrição relacionada com a indisponibilidade de dados de intensidades de precipitação, especialmente em áreas semi-áridas. O estudo pode também servir como suporte estratégico para decisões socioambientais e pode servir como complemento para qualquer estudo, levando em consideração os diferentes fatores de erosão hídrica. Deste modo, os resultados apresentados podem ser considerados como suporte complementar a qualquer estudo e decisão de desenvolvimento hidro-ambiental sobre a bacia hidrográfica da Macta.