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Reduced limbs and limblessness have evolved independently in many lizard clades. Scincidae exhibit a wide range of limb-reduced morphologies, but only some species have been used to study the embryology of limb reduction (e.g., digit reduction in Chalcides and limb reduction in Scelotes). The genus Brachymeles, a Southeast Asian clade of skinks, includes species with a range of limb morphologies, from pentadactyl to functionally and structurally limbless species. Adults of the small, snake-like species Brachymeles lukbani show no sign of external limbs in the adult except for small depressions where they might be expected to occur. Here, we show that embryos of B. lukbani in early stages of development, on the other hand, show a truncated but well-developed limb with a stylopod and a zeugopod, but no signs of an autopod. As development proceeds, the limb's small size persists even while the embryo elongates. These observations are made based on external morphology. We used florescent whole-mount immunofluorescence to visualize the morphology of skeletal elements and muscles within the embryonic limb of B. lukabni. Early stages have a humerus and separated ulna and radius cartilages; associated with these structures are dorsal and ventral muscle masses as those found in the embryos of other limbed species. While the limb remains small, the pectoral girdle grows in proportion to the rest of the body, with well-developed skeletal elements and their associated muscles. In later stages of development, we find the small limb is still present under the skin, but there are few indications of its presence, save for the morphology of the scale covering it. By use of CT scanning, we find that the adult morphology consists of a well-developed pectoral girdle, small humerus, extremely reduced ulna and radius, and well-developed limb musculature connected to the pectoral girdle. These muscles form in association with a developing limb during embryonic stages, a hint that "limbles

Pflanzenkläranlagen (vom Abwasser durch- bzw. überströmte bepflanzte Bodenfilter) werden seit einigen Jahrzehnten erfolgreich zur Abwasserreinigung eingesetzt. Design und Anwendung der Anlagen basieren im Wesentlichen auf Erfahrungswerten. Der Kenntnisstand zu den Reinigungsprozessen innerhalb der Rhizosphäre ist als lückenhaft einzuschätzen. Intensive Grundlagenforschung ist notwendig, um die involvierten Prozesse und deren Wechselwirkungen zu verstehen und letztlich effiziente und erweiterte Anwendungen zu ermöglichen. Dabei können neue Erkenntnisse aus Forschung und Praxis vor allem auch die Möglichkeiten der Nutzung von Pflanzenklärsystemen zur Reinigung von Industrieabwässern maßgeblich erweitern. Insbesondere besteht die Chance der Entwicklung neuer Lösungsansätze zur Kombination von Abwasserreinigung und Wertstoff-/Energiegewinnung.

Anaerobic oxidation of ammonium has become an alternative for the treatment of wastewater with high ammonium loads, and it was also suggested to be involved in the nitrogen removal process in constructed wetlands. Nonetheless, its role has not been well evaluated as yet. In this paper, results of a lab-scale study are presented focusing on the evaluation of the role of Anammox bacteria, plants, applied ammonia, nitrite nitrogen loads, and the presence of organic matter in nitrogen transformation processes in subsurface-flow constructed wetlands. The inoculation of the experimental model wetlands with active Anammox biomass increased the total nitrogen and ammonium removal rates to values up to 5.7 g N/m2 d, which is almost 10 times higher than those values reported for subsurface flow constructed wetlands. Although the presence of plants caused a higher removal rate, the role of the plants became less important with high nitrite influent concentration. Because the unplanted experimental system without the addition of any organic carbon source showed also high nitrogen removal rates, it can be concluded that beside the potential for conventional denitrification in the planted systems the main mechanism for explaining the high nitrogen removal rates obtained during the experiments was the anaerobic ammonia oxidation. The assay of the formation of hydrazine from hydroxylamine and the findings of the molecular biology tests fitted with the positive results for potential Anammox activity obtained in the bottle test. The addition of organic carbon, specifically acetate, apparently had no great influence on Anammox activity, which is in agreement with the findings reported by other authors. Nevertheless, the addition influenced the redox potential. Some questions are still left open, which are mainly associated with the scaling up of these results and the inoculation of Anammox biomass in full-scale systems.

Over the past few years, new technologies for nitrogen removal have been developed mainly because of the increasing financial costs of the traditional wastewater treatment technologies. Newly discovered pathways, like the anaerobic oxidation of ammonium (ANAMMOX), and uses for nitrogen removal technologies are under discussion. Processes and technologies such as: Partial nitrification; Single reactor systems for High Ammonium Removal Over Nitrite (SHARON); Anammox; Aerobic/anoxic deammonification; Oxygen Limited Autotrophic Nitrification-Denitrification (OLAND); Completely Autotrophic Nitrogen Removal Over Nitrite (CANON); wetland based systems, all have a high potential for nitrogen removal. However, the pathways of nitrogen transformation processes are very complex. An understanding of how various environmental factors affect these processes and a sound knowledge of existing, worldwide experience pertaining to these novel technologies are the key if the nitrogen removal rates are to be improved and success is to be realized in full-scale applications. This review describes the present knowledge of the new treatment technologies for wastewater with high nitrogen loads. Special emphasis is given to the influence of environmental factors and the reactor configuration on the nitrogen transformation process and microbial activity.