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The extent of comparable nitrogen removal in the full- and partial-bed biological aerated reactors needs further microbiological evidence, specifically the existence of ammonia-oxidizing bacteria (AOB). The nitrogen removal process in such systems is typically initiated by chemoliautotrophic ammonia-oxidizing bacteria converting ammonia to nitrite and traces of oxidized nitrogen gases. The formation of a dense biofilm as a result of higher turbulence would account for the higher number of AOB cells enumerated in the biofilm samples from the partial-bed reactor (4.3 x [10.sup.5] ± 1.9 x [10.sup.5] No. of AOB cells/mL sample) as compared with those from the full-bed reactor (1.5 x [10.sup.5] ± 8.0 x [10.sup.4] No. of AOB cells/mL sample). Key words: ammonia-oxidizing bacteria, biofilm, suspended growth biomass, fluorescent in-situ hybridization. Il faut plus de preuves microbiologiques pour determiner et comparer l'etendue de l'elimination de l'azote dans les reacteurs biologiques aeres avec lit complet et partiel, plus particulierement en ce qui a trait a l'existence des bacteries oxydant l'ammoniac (<< AOB >>). Le processus d'elimination de l'azote de tels systemes est normalement initie par la conversion de l'ammoniac en nitrites et en traces de gaz d'azote oxyde par les bacteries autotrophes oxydant l'ammoniac. La formation d'un biofilm dense decoulant d'une turbulence superieure dans le reacteur a lit partiel pourrait justifier le plus grand nombre de cellules AOB comptees dans les echantillons de biofilm (4,3 x [10.sup.5] ± 1,9 x [10.sup.5] cellules AOB/mL d'echantillon) provenant de ce reacteur par rapport a celles trouvees dans le reacteur a lit complet (1,5 x [10.sup.5] ± 8,0 x [10.sup.4] cellules AOB/mL d'echantillon) Mots-cles : bacteries oxydant l'ammoniac, biofilm, biomasse en suspension, hybridation in situ par fluorescence. [Traduit par la Redaction], Introduction The importance of understanding the spatial distribution of the microbial population, and its activity, for the optimization of nitrogen removal performance in reactors treating wastewater has been pointed out [...]

Abstract: Effect of reduced media volume on the mixing of biological aerated filters (BAF) was quantitatively determined. The degree of mixing was evaluated based on Reynolds numbers (Re) while the [...]

Background and Objective: Mud spiny lobsters, Panulirus polyphagus (P. polyphagus) are one of the most important fisheries resources now-a-days due to quality that it's possessed. However, there is still lack of in-depth study about this species mainly on males testicular characteristics and sexual maturity size. Therefore, the present study was carried out to investigate the histological characteristics on the testes and sexual maturity sizes of mud spiny lobster, Panulirus polyphagus., Materials and Methods: The testes were dissected out and fixed in 10% buffered formalin solution for 11 h, dehydrated in 70% alcohol and lastly placed in tissue processor for 18±1 h at 60°C. The tissues blocks were cut at the thickness of 4 μm on a rotary microtome. Stained tissues were taken under Advance Microscope (Nikon Eclipse 80i Nomarski DIC). Collected data were analyzed using Microsoft Excel 2013. Data were presented as mean±standard deviation. Statistical analyses were done using one-way ANOVA using SPSS (Version 22)., Results: These lobules of mature P. polyphagus were formed via different germinative lineage cells such as spermatogonia, spermatocytes, spermatids and spermatozoa. The histological characteristics of testes showed that the process of spermatogenesis went through the stages of four testes maturation which were spermatogonia I and II, spermatocytes I and II, spermatids and spermatozoa stages within different body weight of P. polyphagus. It was found that there were significant difference between body weight and carapace length to the testicular maturation stages (one-way ANOVA and p = 0.000)., Conclusion: The results of this experiment indicated that males P. polyphagus have four stages of testes maturation and can be considered to have fully mature testes that ready for fertilization at 452 g body weight (BW) and 107 mm carapace length (CL) or more.

The present study aimed to determine the effect of 17α-hydroxyprogesterone (17α-OHP) and 17α-hydroxypregnenolone (17α-OHPL) on sperm quality and sperm quantity in male mud spiny lobster (Panulirus polyphagus). The mean of sperm quality was increased in 17α-OHP and 17α-OHPL treated hormones. In 17α-OHP injected animals, the mean of sperm quantity of dose 0.01 μg g(-1) b.wt. was increased than 17α-OHPL. Meanwhile, 17α-OHP and 17α-OHPL concentrations were lower when injected with the hormones but 17α-OHP was higher at only day 15 (dose 0.01 and 0.1 μg g(-1) b.wt.). For 17α-OHPL, the hormone was a prohormone in the body of P. polyphagus and only required smaller to increase the sperm quantity. Besides, when the higher dose of 17α-OHPL (0.1 μg g(-1) b.wt.) was used in P. polyphagus, the development of P. polyphagus was inhibited and decreased the sperm quantity and 17α-OHPL concentration in hemolymph was lower. Injection of 17α-OHP in P. polyphagus has increased the sperm quality and quantity for both 17α-OHP dosage of 0.01 and 0.1 μg g(-1) b.wt. However, injection of 17α-OHPL in P. polyphagus has decreased the sperm quantity only, also for both dosage of 0.01 and 0.1 μg g(-1) b.wt. and lower on hormone concentration.

The present study aimed to determine the effect of testosterone undecanoate hormone on sperm quality (sperm viability) and sperm quantity (sperm counts) and its levels in the hemolymph of male mud spiny lobster, Panulirus polyphagus. Male P. polyphagus was injected laterally in fifth abdominal segment of pure hormone, Testosterone Undecanoate (TU) and ethanol at days 1, 8, 15, 22 and 29. Hemolymph of P. polyphagus was taken every two weeks and checked with Enzyme-linked immunosorbent assay (ELISA) to measure hormone levels. The mean sperm quality and quantity were increased due to increase the TU dose and TU levels also increase. The sperm quality, quantity and hormone levels were relevance each others. These findings indicate that TU injection should be evaluated as a practical way of improving sperm quality and quantity in commercial operations.