Effect of tillage practices on the soil carbon dioxide flux during fall and spring seasons in a Mediterranean Vertisol

In this study, we assessed the effect of conventional tillage (CT), reduced (RT) and no tillage (NT) practices on the soil CO2 flux of a Mediterranean Vertisol in semi-arid Morocco. The measurements focused on the short term (0 to 96 h) soil CO2 fluxes measured directly after tillage during the fall and spring period. Soil temperature, moisture and soil strength were measured congruently to study their effect on the soil CO2 flux magnitude. Immediately after fall tillage, the CT showed the highest CO2 flux (4.9 g m-2 h-1); RT exhibited an intermediate value (2.1 g m-2 h-1) whereas the lowest flux (0.7 g m-2 h-1) was reported under NT. After spring tillage, similar but smaller impacts of the tillage practices on soil CO2 flux were reported with fluxes ranging from 1.8 g CO2 m-2 h-1 (CT) to less than 0.1 g CO2 m-2 h-1 (NT). Soil strength was significantly correlated with soil CO2 emission; whereas surface soil temperature and moisture were low correlated to the soil CO2 flux. The intensity of rainfall events before fall and spring tillage practices could explain the seasonal CO2 flux trends. The findings promote conservation tillage and more specifically no tillage practices to reduce CO2 losses within these Mediterranean agroecosystems. (Résumé d'auteur

Dietary fat intake as a risk factor for the development of diabetes. Multinational, multicenter study of the Mediterranean Group for the Study of Diabetes (MGDS)

In the context of the Multinational MGSD Nutrition Study, three groups of subjects were studied: 204 subjects with recently diagnosed diabetes(RDM),42subjectswithundiagnoseddiabetes(UDM)(AmericanDiabetesAssociation criteria—fasting plasma glucose [FPG] 126 mg/dl), and 55 subjects with impaired fasting glucose(IFG)(FPG 110and126mg/dl).Eachgroupwascomparedwithacontrolgroupof nondiabetic subjects, matched one by one for center, sex, age, and BMI. Nutritional habits were evaluated by a dietary history method, validated against the 3-day diet diary. In RDM, the questionnaire referred to the nutritional habits before the diagnosis of diabetes. Demographic data were collected, and anthropometrical and biochemical measurements were taken. RESULTS— Compared with control subjects, RDM more frequently had a family history of diabetes(49.0vs.14.2%;P0.001),exercisedless(exerciseindex53.5vs.64.4;P0.01),and more frequently had sedentary professions (47.5 vs. 27.4%; P 0.001). Carbohydrates contributed less to their energy intake (53.5 vs. 55.1%; P 0.05), whereas total fat (30.2 0.5 vs. 27.8 0.5%; P 0.001) and animal fat (12.2 0.3 vs. 10.8 0.3%; P 0.01) contributed moreandtheplant-to-animalfatratiowaslower(1.50.1vs.1.80.1;P0.01).UDMmore frequentlyhadafamilyhistoryofdiabetes(38.1vs.19.0%;P0.05)andsedentaryprofessions (58.5vs.34.1%;P0.05),carbohydratescontributedlesstotheirenergyintake(47.61.7vs. 52.81.4%;P0.05),totalfat(34.71.5vs.30.41.2%;P0.05)andanimalfat(14.2 0.9 vs. 10.6 0.7%; P 0.05) contributed more, and the plant-to-animal fat ratio was lower (1.6 0.2 vs. 2.3 0.4; P 0.05). IFG differed only in the prevalence of family history of diabetes (32.7 vs. 16.4%; P 0.05). CONCLUSIONS— Our data support the view that increased animal fat intake is associated with the presence of diabetes

Tillage system affects soil organic carbon storage and quality in Central Morocco

Stabilizing or improving soil organic carbon content is essential for sustainable crop production under changing climate conditions. Therefore, soil organic carbon research is gaining momentum in the Mediterranean basin. Our objective is to quantify effects of no tillage (NT) and conventional tillage (CT) on soil organic carbon stock (SOCs) in three soil types (Vertisol, Cambisol, and Luvisol) within Central Morocco. Chemical analyses were used to determine how tillage affected various humic substances. Our results showed that, after 5 years, surface horizon (0–30 cm) SOC stocks varied between tillage systems and with soil type. The SOCs was significantly higher in NT compared to CT (10% more in Vertisol and 8% more in Cambisol), but no significant difference was observed in the Luvisol. Average SOCs within the 0–30 cm depth was 29.35 and 27.36 Mg ha−1 under NT and CT, respectively. The highest SOCs (31.89 Mg ha−1) was found in Vertisols under NT. A comparison of humic substances showed that humic acids and humin were significantly higher under NT compared to CT, but fulvic acid concentrations were significantly lower. These studies confirm that NT does have beneficial effects on SOCs and quality in these soils

L'hypersensibilité des récepteurs dopaminergiques induite par des injections chroniques unilatérales intracaudales de l'anticorps anti-idiotypique dopaminergique

La contribution des mécanismes immunologiques dans la genèse de la maladie de Parkinson est très controversée. Des injections chroniques unilatérales dans le noyau caudé (1 injection par semaine pendant 5 semaines) de l’anticorps anti-idiotypique de la dopamine conjuguée (AIDA) ou de l’halopéridol semblent induire, une semaine après la dernière injection, une hypersensibilité des récepteurs dopaminergiques révélée par l’injection de faibles doses d’apomorphine. Cette hypersensibilité se traduit par un comportement de rotation controlatérale au site d’injection

Optimización de la extracción de aceite de semilla de dátil mediante la ayuda de tecnologías hidrotermales y de ultrasonido

The date seed is a by-product from the date industry. Its use as a source of added-value compounds is of great interest. Oil accounts for 5-13% of the seed’s weight. Soxhlet extraction with organic solvents is the traditional method for obtaining oil from seeds. In this work, hydrothermal pre-treatments and sonication are proposed to make the extraction a more environmentally friendly process. Factors such as sonication time and temperature and hexane-to-seed ratio (H/S) have been considered. Response surface methodology was applied for optimization. Hydrothermal treatments increased oil recovery. H/S was the most influential factor, and was close to 7 mL/g seeds for both samples. 71% recovery was achieved for native seeds after 15 min sonication at 45 ºC, and 80% for 180 ºC-treated seeds after 45 min at 35 ºC when compared to Soxhlet extraction. These conditions comply with our initial aim. Pre-treatments seem to have a negative effect on oil stability, although this observation needs to be confirmed.La semilla de dátil es un subproducto de la industria datilera. Su uso como fuente de compuestos de valor añadido sería muy interesante. El aceite representa el 5-13% del peso de la semilla. La extracción mediante Soxhlet con disolventes orgánicos es el método tradicional para obtener aceite de semillas. En este trabajo se proponen pretratamientos hidrotérmicos y sonicación para diseñar un proceso de extracción más respetuoso con el medio ambiente. Se han considerado factores como el tiempo y la temperatura de sonicación y la proporción hexano/semilla (H/S). La optimización del proceso se llevó a cabo por el método de superficie de respuesta. Los tratamientos hidrotérmicos aumentaron el porcentaje de recuperación. El factor más influyente fue H/S, y su valor óptimo estuvo cerca de 7 mL/g para ambas muestras. La recuperación óptima fue del 71% para las semillas sin tratamiento tras 15 min de sonicación a 45 ºC, y del 80% para las semillas tratadas a 180 ºC después de 45 min a 35 ºC. Estos resultados cumplen con nuestro objetivo inicial. Sin embargo, los pretratamientos parecen tener un efecto negativo sobre la estabilidad del aceite, lo que se confirmará en estudios posteriores

Design and Characterization of a Compact Single Layer Modified S-Shaped Tag Antenna for UHF-RFID Applications

In this paper, we report the design of a new compact single layer modified S-shaped tag antenna for UHF-RFID applications. To achieve a compact size of 51×34 mm2 for this tag antenna, the technique of using S shaped strip is applied, and by further adding a pair of equilateral triangular stubs into this structure, good impedance matching can be obtained at 915 MHz, which is the center frequency of the North-American UHF-RFID band (902 to 928 MHz). Besides exhibiting acceptable 5m read range in free space at 915 MHz, the proposed design shows a read range of about 4.5 when mounted on a metallic object (200 ×30 cm2) separated by spacer foam of thickness 1 cm. Furthermore, the proposed design shows a reasonable read ranges when it is mounted on different dielectrics with low permittivity. The proposed design has a simple configuration, low cost, acceptable read range, and can work on various background materials. &nbsp

La fertilisation améliore la production des prairies humides naturelles dans la montagne du haut Atlas oriental du Maroc : cas de la région d'Imilchil

The oriental High Atlas mountains in southeast of Morocco are characterized by small natural wet grasslands called “Almous”, they are suitably well managed by the local population. They are destined to feed cattle and mullets. This trial was implemented in order to assess the effects of nitrogen fertilization on the phytomass production on the Tissila meadow (6.5 Ha) in Imilchil region. The experimental design consisted in dividing the meadow into 3 parcels. One parcel is leaved as control and the other two parcels have received two doses of nitrogen during three periods in the year (D1 =67 kg N/ha (split in three applications October, April and May) plus 46 Kg P2O5/ha (split in two applications April and May); D2 (with applications as D1=134kg N/ha more 46 Kg P2O5/ha; D3 = control). The phytomass production has doubled in Tissila region due to the effect of fertilization basically for dose (D2). The assessment of flora revealed a great specific richness (79 species) and some endemism.Les montagnes orientales du Haut Atlas au sud-est du Maroc sont caractérisées par de petites prairies humides naturelles applées "Almous" elles sont convenablement bien gérées par la population locale. Ellesont destinées à nourrir les bovins et mulets. Un essai a été réalisé pour évaluer les effets de la fertilisation azotée sur la production de la prairie de Tissila, (6,5 Ha) dans la région d'Imilchil. Le plan expériemental consistait à diviser la praiire en 3 parcelles. Une parcelle est laissée comme témoin et les deux autres parcelles ont reçu deux doses d'azote pendant trois périodes de l'année (D1 = 67 kg N / ha (réparti en trois applications en octobre, avril et mai) plus 46 kg de P2O5 / ha  en deux applications (en avril et mai); D2 (avec les mêmes applications en D1) = 134 kg N / ha plus 46 kg P2O5 / ha; D3 = contrôle). La production de phytomasse a doublé dans la région de Tissila en raison de l'effet de la fertilisation surtout pour la D1. L'évaluation de la flore a révélé une grande richesse spécifique (79 espèces) et une certaine endémicité qui mérité d'être sauvegardée

Salsola vermiculata espèce prometteuse pour la réhabilitation des pâturages présahariens du Maroc

Salsola vermiculata L. Syn. Caroxylon villosum (Delile) Akhani & Roalson (Chenopodiaceae) is a perennial small woody species widely distributed in arid zones of Middle East and North Africa (MENA) region. It is one of the promising pastoral species for the rehabilitation of arid rangelands in Mororcco. The objectives of this study were to determine the effects of temperature and duration of seed storage on the germination of Salsola vermiculata, to determine the optimal transplant age of Salsola vermiculata seedlings and to compare the production of two varieties of Salsola vermiculata (villosa and brevifolia). The germination tests were carried out in a germination incubator at the laboratory of the Errachidia experimental station. 12 temperature regimes and three durations of seed storage were tested. For transplantation, comparisons were made between villosa variety seedlings of 1.5 months, 4 months and 8 months. In addition, the production the 8-month-old seedlings of the two varieties of Salsola vermiculata (var. villosa and var. brevifolia) were compared. The percentage of germination and the germination rate were very high for several temperature regimes, except for the high temperatures. In addition, it decreased very significantly with the storage duration of the seeds. Regarding the age of seedling transplants, the eight-month-old seedlings were the best in terms of production and growth rate. In addition, the villosa variety produced very significantly more phytomass than the local variety brevifolia.Salsola vermiculata L. (Chenopodiaceae) est une ligneuse basse largement répandue dans les zones arides du Moyen-Orient et de l’Afrique du Nord (MENA). C'est l'une des espèces pastorales prometteuses pour la réhabilitation des pâturages arides du Maroc. Les objectifs de cette étude sont de déterminer les effets de la température et de la durée de stockage des graines sur la germination de Salsola vermiculata, de déterminer l’âge optimal de transplantation des plantules de Salsola vermiculata et de comparer la production de deux variétés de cette espèce (variétés villosa et brevifolia). Les essais de germination sont menés dans une enceinte de germination au laboratoire de la station expérimentale d'Errachidia. Douze régimes de température et trois durées du stockage de graines sont testés. Pour la transplantation, des comparaisons sont effectuées entre des plants de 1.5 mois, 4 mois et 8 mois de la variété villosa. En outre, la comparaison de la production des plantules de 8 mois des deux variétés de Salsola vermiculata (villosa et brevifolia) sont effectuées. Les résultats montrent que le pourcentage de germination et la vitesse de germination sont très élevés pour plusieurs régimes de température, sauf pour les hautes températures. En outre, ils diminuent très significativement avec la durée de stockage des graines. Concernant, l’âge de transplantation, les plantules de 8 mois se comportent mieux des points de vue reprise, production et croissance. En outre, la variété villosa a produit très significativement plus de phytomasse que la variété locale brevifolia

Effet à long terme d'injections intracérébroventriculaires d'anticorps dopaminergiques sur l'hypersensibilité comportementale chez la souris

ln the present study the effect ofrepeated intracerebroventricular (ICV) of anti-conjugated dopamine antibodies (Acm anti-DAc) was investigated on behavioural supersensitivity and eating behavior. Mice were injected in ICV (with an ICV cannula) with either Acm anti-DAc or no immuns immunoglobulins (IgNI) twice a week for 5 weeks, their behavioural supersensitivity to apomorphine (0.05 mglkg) were measured. The results showed that Repeated intracerebroventricular injections of anti conjugated dopamine antibodies produced a behavioural supersensitivity to apomorphine. Immunohistochemical analysis showed that the behavioural supersensitivity is not due to DA celllosses in the substantia nigra or the ventral tegmentum area. Key words: Dopaminergic antibodies, Intracerebroventricular injections, Behavioural supersensitivity, Mice  Des injections intracérébroventriculaires répétées de l'anticorps monoclonal anti-dopamine conjuguée (ACm antiDAc) chez des souris Balb/c entraînent, pendant 8 semaines après la fin des injections, une hypersensibilité comportementale. L'analyse immunohistochimique montre que cette hypersensibilité ne semble pas liée directement à une perte des cellules DA dans la substance noire et dans l'aire tegmentale ventrale. Mots clés: Anticorps dopaminergiques, Injections intracérébroventriculaires, Hypersensibilité comportementale, Souri