Les différentes sortes de pédagogie

Depuis les années 1980 , le terme « didactique » a été largement utilisé  pour identifier les notions relatives à l’acte éducatif dès lors qu’elles auront le trait scientifique. Un débat profondément établi pour définir, déterminer et aussi pour distinguer entre les différents termes qui décrivent l’acte pédagogique « éducation-pédagogie-didactique » منذ الثمانينيات بإمكاننا ان نلاحظ الاستعمال الواسع لمصطلح التعليمية  للتعبير عن الأعمال المتعلقة بالفعل التربوي بمجرد ان تأخذ الطابع العلمي.لقد قام جدال عميق من أجل تعريف و تحديد التمييز بين التربية و البيداغوجية والتعليمية  في وصف الفعل التربوي. 

Selection of an efficient in vitro micropropagation and regeneration system for potato (Solanum tuberosum L.) cultivar Desirée

Sprouts of about 40 to 80 mm length were excised, surface sterilized with 70% CloroxR and cultured on solid full-strength Murashige and Skoog (MS) medium. Shoot nodal segments (1.0 cm) from in vitro plantlets (2 to 4 weeks old) were multiplied through periodic subculturing on full-strength MS medium with 30 g/L sucrose, 100 ml/L myo-inositol and 0.5 ml/L silver thiosulfate. The shoots were rooted on the same medium. Microtubers were stimulated on MS medium supplemented with 80 g/L sucrose, 100 ml/L myo-inositol and 5 ml/L benzyl adenine. They generally originate on aerial etiolated shoots producing . 1.0 } 0.5 microtuber/explant with diameter approx. 3 to 10 mm. Shoot regeneration was performed from  tuber discs, internodes and leaf explants using 6 different media. Different regeneration capacities were  observed by the explants along 60 days. The average number of shoots was highest from tuber discs (6.2)  than from leaf explants (2.6) which exceeds about three times; no shoot from internode explants cultured on the various media. Regenerated plantlets produced from both tuber discs and leaf explants exhibited random amplification of polymorphic DNA (RAPD) analysis using five selected primers to detect  somaclonal variation. All the morphological variants were excluded. One of the regenerated plantlet  derived from leaf-explants was true-to-type to the main in vitro plantlet, so it will be used as a source of explants for transformation experiments. The other regenerated plantlets derived from leaf explants and tuber discs show the presence and/or absence of polymorphic bands. Results also showed that  microtubers were initiated on the etiolated shoots of the regenerants at the first 10 days. The etiolated shoots induced about 2.6 } 0.6 and 2.2 } 0.5 microtuber/explants.Key words: Solanum tuberosum L., seed tuber, sprouting, micropropagation, microtubers, explants, regeneration, random amplification of polymorphic DNA (RAPD)

Comparaison des objectifs attribués à l’éducation physique en Algérie et en Belgique francophone.

Cette étude se base essentiellement sur le concept de la représentation de l'éducation physique et de ses objectifs. Dans les pays occidentaux, cette discipline scolaire est généralement bien appréciée par les élèves. Il s'avère intéressant de vérifier si cette situation est influencée par des aspects culturels et, ainsi déterminer si les acteurs de la relation didactique développent d'autres représentations dans le monde arabe

Synthesis of antibacterial additive for metal working fluids application

Metalworking fluids, the class of lubricants most susceptible to microbial attack, metalworking fluid must also be safe for human use and exposure, The failure of the fluid to perform any of its functions has the potential to result in operational problems, process shutdowns, decreased tool life, and product-quality issues, all of which will result in increased costs. Perhaps one of the most common and controllable complications is microbial degradation specially standing from the fact that metalworking fluids contain the nutrients that can permit unchecked microbial growth. In this work we prepared Antimicrobial metal working fluid additive which fulfills the criteria of successful local production in Egypt, as the commercial availability of starting components, effectiveness of the prepared additive, easiness of addition and homogenization with other MWF additives, good environmental profile and biodegradability. The effectiveness of the prepared additive was evaluated by standard method ASTM E645-97 test. It was revealed that; the formic acid which condensate with the polyethylene glycol 400 and ethylene glycol had excellent antibacterial action, it could also greatly reduce growth of bacteria

Synthesis of antibacterial additive for metal working fluids application

Metalworking fluids, the class of lubricants most susceptible to microbial attack, metalworking fluid must also be safe for human use and exposure, The failure of the fluid to perform any of its functions has the potential to result in operational problems, process shutdowns, decreased tool life, and product-quality issues, all of which will result in increased costs. Perhaps one of the most common and controllable complications is microbial degradation specially standing from the fact that metalworking fluids contain the nutrients that can permit unchecked microbial growth. In this work we prepared Antimicrobial metal working fluid additive which fulfills the criteria of successful local production in Egypt, as the commercial availability of starting components, effectiveness of the prepared additive, easiness of addition and homogenization with other MWF additives, good environmental profile and biodegradability. The effectiveness of the prepared additive was evaluated by standard method ASTM E645-97 test. It was revealed that; the formic acid which condensate with the polyethylene glycol 400 and ethylene glycol had excellent antibacterial action, it could also greatly reduce growth of bacteria

Identification of a Cucumber Mosaic Virus from <i>Cucurbita pepo</i> on New Reclamation Land in Egypt and the Changes Induced in Pumpkin Plants

In 2020, the leaves and fruit of 50 pumpkin plants with suspected cucumber mosaic virus (CMV) symptoms of leaf mosaic, vein yellowing, and mild leaf curling were collected from Sharq El-Owainat (Al Wadi El-Gaded governorate), a new reclamation land in Egypt. This study was aimed at deciphering and characterizing the causal agent of the leaf yellowing disease associated with pumpkin plants in Egypt. The causal agent was identified by serological, cytological, and molecular means. The serological identification by DAS–ELISA confirmed the presence of CMV in 20% of the plants. The cytological identification by electron microscopy revealed typical cucumovirus isometric particles of 28–30 nm diameter in the cytoplasm of the leaf parenchyma, epidermal cells, the integument, and the nucleus. Molecular characterization by one-step reverse transcriptase-PCR yielded the required size of amplicon (678 bp) for CMV. Additionally, mechanical sap inoculation was used to determine the host range and symptomatology of the isolated CMV in seventeen different plant species belonging to six different plant families. CMV replicated, moved systemically, and induced a range of symptoms in sixteen plant species. The isolated CMV was transmitted to pumpkin plants at a 16.4% rate by seeds. CMV-infected pumpkin plant leaves were characterized by a substantially low concentration of photosynthetic pigments, a high level of reducing sugars, relatively low protein levels, and a significant increase in total phenol contents, implying their potential role as antiviral agents. Ultrathin sections of infected cells revealed histological changes and cytological abnormalities in comparison to healthy plants. This is the first identification of CMV on new reclamation land in Egypt, pinpointing its swift spread, which could pose a major constraint to pumpkin production in Egypt

Pancreatic surgery outcomes: multicentre prospective snapshot study in 67 countries

Background: Pancreatic surgery remains associated with high morbidity rates. Although postoperative mortality appears to have improved with specialization, the outcomes reported in the literature reflect the activity of highly specialized centres. The aim of this study was to evaluate the outcomes following pancreatic surgery worldwide.Methods: This was an international, prospective, multicentre, cross-sectional snapshot study of consecutive patients undergoing pancreatic operations worldwide in a 3-month interval in 2021. The primary outcome was postoperative mortality within 90 days of surgery. Multivariable logistic regression was used to explore relationships with Human Development Index (HDI) and other parameters.Results: A total of 4223 patients from 67 countries were analysed. A complication of any severity was detected in 68.7 percent of patients (2901 of 4223). Major complication rates (Clavien-Dindo grade at least IIIa) were 24, 18, and 27 percent, and mortality rates were 10, 5, and 5 per cent in low-to-middle-, high-, and very high-HDI countries respectively. The 90-day postoperative mortality rate was 5.4 per cent (229 of 4223) overall, but was significantly higher in the low-to-middle-HDI group (adjusted OR 2.88, 95 per cent c.i. 1.80 to 4.48). The overall failure-to-rescue rate was 21 percent; however, it was 41 per cent in low-to-middle-compared with 19 per cent in very high-HDI countries.Conclusion: Excess mortality in low-to-middle-HDI countries could be attributable to failure to rescue of patients from severe complications. The authors call for a collaborative response from international and regional associations of pancreatic surgeons to address management related to death from postoperative complications to tackle the global disparities in the outcomes of pancreatic surgery (NCT04652271; ISRCTN95140761)