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Metallic Foil Friction Stir Welding (MFFSW) was newly developed from the Friction Stir Welding (FSW) technique. Magnesium (Mg) alloys were the most trending alloys in the aerospace, automobile, and biomedical industries. This study aims to investigate the variation in mechanical, corrosive, microstructural, and fractographic properties of MFFSW as a process innovation when compared with FSW. The metallic foil of pure manganese (Mn) with a thickness of 500 μm was inserted between two AZ61 Mg alloys. The tensile strength, impact strength, and hardness were noted as mechanical properties of the output. Potentiodynamic corrosion tests were performed to reveal the corrosion properties. An optical microscope was used to examine a distinct transverse section of the weld. Fractography tests with scanning electron microscopic analysis were conducted on destructive tensile specimens. The ultimate tensile strength, impact energy, yield strength, and microhardness increased to 16%, 32%, 12%, and 19.17%, respectively, compared to FSW. MMFSW shows a lower elongation of up to 33% than FSW. MMFSW (9.61 mm/A) shows a lower corrosion rate than FSW (11.02 mm/A), which employs improved corrosion properties. Optical microscopy images of the stir zone in both MFFSW and FSW revealed that adding a Mn alloying element improved grain growth uniformity and eliminated unexpected grain growth patterns. Hence, the experiment's conclusion shows that MFFSW has the edge over FSW for mechanical and corrosion properties. Thus, the Mn strip improves the properties of MFFSW. [ABSTRACT FROM AUTHOR]

This review article is focused on internal flesh browning (IFB)-related physiological disorders affecting apple (Malus domestica Borkh.) fruit. The expression of different physiological and metabolic IFB-related disorders during post-harvest storage are investigated along with the pre-harvest factors contributing to development. The effectiveness of commercially available pre-harvest technologies for preventing IFB-related disorders are also examined. Internal flesh browning-related disorders are erratic and devastating disorders that result in post-harvest deterioration of fruit quality in apples. Internal flesh browning-related disorders can result in severe economic losses to the apple industry through reduced consumer trust and market acceptability of susceptible cultivars. There are several IFB-related disorders and incidence can range from 0 to 100% of a crop, with severity ranging from no brown flesh to browning of the entire fruit flesh. While IFB-related disorders are found in several apple cultivars, some cultivars are more prone than others. The development of IFB-related disorders involve complex mechanisms depending upon the different types and causes, or factors involved in loss of structural integrity and functional stability of the cell membranes and cell components. Membrane disruption followed by enzymatic oxidation of fruit phenolic compounds by polyphenol oxidases and the production of brown polymers is considered to be the general underlying mechanism causing the browning of flesh tissue. It can be observed in different patterns based on the injured portion of the fruit flesh and the cause of membrane disruption. Three broad categories of IFB-related disorders, including chilling injury, internal CO2 injury, and senescent-related browning disorders, are discussed along with their sub-types. The development of IFB-related disorders can be influenced by both pre-harvest factors and post-harvest conditions and their interactions. Although commonly associated with storage, IFB can also be found immediately after harvest and sometimes in unharvested fruit prior to full maturity. As pre-harvest conditions are a strong contributor to IFB-related disorders, the influence of several pre-harvest orchard conditions, including fruit size, crop load, maturity at harvest, cultivar, climatic conditions, seasonal temperatures, growing degree days, and major mineral nutrients, such as nitrogen (N), phosphorus (P), potassium (K), and calcium (Ca) are reported. Although there are contradictory findings in the studies reported, in general, factors such as larger fruit size, light crop load and delayed harvesting, along with cool temperatures after bloom and warmer temperatures before harvest, increase the risk of IFB-related disorders. In relation to fruit mineral concentrations, high N and low Ca have been associated with increasing IFB, while there is conflicting evidence in relation to the impact of both P and K. This review also examines the effectiveness of commercial pre-harvest technologies such as 1-methylcyclopropene, aminoethoxyvinylglycine and diphenylamine in the prevention of IFB-related disorders, but none of these technologies were found promising due to varied and contradictory results. [ABSTRACT FROM AUTHOR]

The study describes the in vivo activity of Lactobacillus casei in malnourished Giardia lamblia-infected BALB/c mice. By experimentation, it was found that daily administration of the probiotic 7 days before inoculation with Giardia trophozoites in malnourished mice efficiently reduced both the severity and duration of giardiasis. More specifically, excretion of Giardia cysts and trophozoites counts were reduced, while faecal lactobacilli counts increased significantly in probiotic-fed malnourished mice, compared with control mice. Interestingly, it was also observed that oral feeding of the probiotic to malnourished mice abrogated all the anthropometric and biochemical anomalies. Histologically, morphological and cellular alteration of microvillus membrane integrity revealed that probiotic administration ameliorated the mucosal damage in malnourished, probiotic-inoculated, Giardia-infected mice compared with the severe microvillus atrophy, œdematous and vacuolated epithelial cells, and ileitis in malnourished Giardia-infected mice. The results clearly show the antigiardial effect of the probiotic in vivo by modulating the gut cells to inhibit the colonization and multiplication of Giardia trophozoites, thus reducing the severity and duration of murine giardiasis. Cette étude décrit l'activité de Lactobacillus casei in vivo chez des souris BALB/c malnutries et infectées par Giardia lamblia. Expérimentalement, l'administration quotidienne de probiotiques 7 jours avant l'inoculation de trophozoïtes de Giardia aux souris malnutries des réduisait efficacement tant la sévérité que la durée de la lambliase. Plus spécifiquement, l'excrétion de kystes de Giardia et la numération de trophozoïtes étaient réduites alors que les comptes de lactobacilles fécales augmentaient significativement chez les souris malnutries ayant reçu des probiotiques, comparativement aux souris contrôles. Fait intéressant, l'administration orale de probiotiques chez les souris malnutries annulait toutes les anomalies morphologiques et biochimiques. Histologiquement, la modification morphologique et cellulaire de l'intégrité de la membrane des microvillosités a révélé que l'administration de probiotiques atténuait les dommages causées par Giardia aux muqueuses des souris malnutries, alors que les souris malnutries et infectées n'ayant pas reçu de probiotiques présentaient une atrophie sévère des microvillosités, des cellules épithéliales oedémateuses et vaculolées ainsi que des signes d'iléite. Ces résultats démontrent clairement l'effet anti-lambliase des probiotiques in vivo, par la modulation de la capacité des cellules de l'intestin à inhiber la colonisation et la multiplication des trophozoïtes de Giardia, réduisant ainsi la sévérité et la durée de la lambliase chez la souris. [ABSTRACT FROM AUTHOR]