The fabella has been mainly studied using imaging methods but there are less research reports on the gross anatomical studies. We performed this anatomical study of the fabella and its surrounding structures with functional implications using 150 heads of the gastrocnemius muscles of 75 knees from 39 Japanese cadavers. This study is the direct representation of the human fabella and its functional implications. We observed 99 fabellae (66.0%) including 44 complete bony fabellae (29.3%). Of these bony fabellae, 43 (97.7%) were located in the lateral head of the gastrocnemius muscle with its surrounding structures and were positioned only on the lateral condyle of the femur. Moreover, the cartilage and bony fabellae, especially on the lateral side, contributed to the fabella complex with its surrounding muscles and ligaments and formed small articular cavity by cooperating with the femoral condyle. Although the human fabella is considered as appearing in the fabella complex with ageing and it possibly induces clinical symptoms, the fabella may play an important role as a stabilizer between the fabella complex and the femoral condyle.

Summary: To examine the three-dimensional structure of the perivascular glial limiting membrane (Glm) and its relationship with the vasculature in rat/mouse cerebral cortices, serial ion-etched plastic sections were observed under the scanning electron microscope and their images were reconstructed. In the case of arterioles and venules close to the pial surface, cord-like principal processes predominantly formed the endfeet; whereas in the case of capillaries and venules, sheet-like secondary processes chiefly formed Glm. Moreover, it was found that several plate-like structures protruded from the basement membrane surrounding the arterioles to penetrate into the astrocytic somata. The perivascular Glm was formed by monolayers of astrocytic processes and/or somata irrespective of the types of blood vessel. However, the thickness of the perivascular Glm, varied greatly according to the type of blood vessel. The thickness of Glm decreased in the order of arterioles, venules and capillaries. The outer surface of the perivascular Glm was extremely irregular, and sheet-like processes arising from this Glm infiltrated into the surrounding neuropil.

Ammonia is regarded as one of the alternative fuels and regarded as a "hydrogen carrier". Ammonia is an easily-liquefiable fuel. Therefore, it is a suitable fuel for transportation and storage. Also, ammonia can be produced in large quantities by using the Haber-Bosch process with low price. It is known that the laminar burning velocity of ammonia/air mixture is about 10 cm/s at near stoichiometric condition. This laminar burning velocity is very low compared with that of other fossil fuels. Therefore, in order to use ammonia as the alternative fuel, it is necessary to improve the laminar burning velocity of ammonia mixture. In this study, the oxygen-enriched combustion was applied to an ammonia/N 2 /O 2 premixed flame and the effects of the oxygen-enriched combustion on the flammable range, the laminar burning velocity and the flame temperature were evaluated. Also, laminar burning velocity was calculated by using CHEMKIN-Pro. The chemical reaction set about ammonia oxidation, which reported by Lindstedt, was applied as the detailed elementary reactions. Results showed that oxygen concentration was necessary at least 26% to maintain ammonia flame stable. The laminar burning velocity was increased with the increase of O 2 concentration in both experimental results and numerical results. At 30% O 2 concentration and stoichiometric condition, the laminar burning velocity was 27.4 cm/s. Also, Ammonia flame temperature was around 2167 K under 30% O 2 concentration.

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Ammonia is regarded as one of the alternative fuels, since the physical properties of Ammonia is a suitable fuel for transportation and storage as a "hydrogen carrier". Also, a large amount of ammonia can be produced easily through the Haber-Bosch process with low price. To use ammonia as the alternative fuel, it is necessary to pay attention to Fuel-NOx formation. In this study, the oxygen-enriched combustion was applied to an ammonia/N 2 /O 2 premixed flame to make the flame stable. The effects of the oxygen-enriched combustion on characteristics of NOx formation and on the unburned ammonia remained in the burned gas were evaluated. Results showed that NO concentration reached to 1.2%, and unburned ammonia wasn't detected in all O 2 concentration conditions of fuel lean mixture. Also, NO concentrations sharply decreased between = 1.0 to = 1.4. At the condition of = 1.4, NO concentration was 600 ppm. Unburned ammonia wasn't detected between the condition of = 0.9 to = 1.1, and over the condition of =1.2, ammonia concentration was increased steeply. The sum of (NO + NH 3 ) became the minimum value around the condition of = 1.3 and = 1.4. These characteristics that the NOx formations depended on equivalence ratio were the same characteristics of NOx formation when propane is added to NH 3 as a fuel.

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