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Background: The use of local perforator flaps recently arose as an alternative to free flaps for lower extremity reconstruction. In this paper, a single surgeon's experience is discussed in the reconstruction of lower extremity defects with the use of local perforator flaps. Aim: This study speculates the impact of risk factors on local perforator flap outcome and reoperation rates. Study Design: This study is a retrospective study. Materials and Methods: Between December 2013 and December 2020, a total of 51 lower extremity defects were reconstructed using local perforator flaps. Patients were categorized based on risk factors including diabetes mellitus, hypertension, venous insufficiency of the lower extremity, cigarette smoking, and being older than 60 years in addition to the number of risk factors each patient bear. Partial flap necrosis rates, total flap necrosis rates, reoperation rates and their relationship with risk factors were assessed. Results: Out of 51 local perforator-based flaps, no total flap loss and four partial flap loss were encountered. Patients older than 60 years old, hypertensive patients, patients who are smokers, and patients with multiple risk factors had higher partial flap loss rates. In addition, diabetic patients, patients older than 60 years old, and patients bearing multiple risk factors are shown to have higher reoperation rates. Conclusion: Meticulous operative planning and considering the risk factors each patient bear are important in the reconstruction of lower extremity defects. Therefore, risk factors identified in this study must be evaluated during patient selection in the reconstruction of lower extremity defects using local perforator flaps.

The synergistic effect of co-pyrolysis for the mixtures of sewage sludge (SS), rice straw (RS) and composite plastic wastes (PE&PP) has been investigated with the aim of high gas yields and hydrogen generation. In this context, the applicability of high temperature pyrolysis technology was evaluated at both rotary type batch reactor and rotating screw type continuous reactor operating under the industrially relevant conditions. Gas yields have been improved at increasing the operating temperatures up to 850 °C. The gas yield of 75.06 % with its H2 portion of 32.35 % has been achieved as the best results for continuous pyrolysis unit at pilot scale. Secondary reactions such as steam de-alkylation, steam cracking, water gas shift and so on were regarded as being responsible for the high gas yields when the primary products of pyrolysis, i.e. condensable vapors, were much exposed to the hot zones inside the reactor. The dehydration of organic components involving the loss of water may supply steam to create a reactive pyrolysis atmosphere. While the pyrolysis of sewage sludge and rice straw favors CO and CO2 formation due to the high oxygen contents of these feedstocks, more methane and light olefins were produced when the plastics were added to the feedstock blends. This was ascribed to the initially generated radicals from the decomposition of sewage sludge and/or rice straw that might promote the scission reactions of plastics towards volatiles. It was shown that high temperature pyrolysis can be applied to a variety of organic wastes such as rice straw, sewage sludge and waste plastics. Conversion of wastes to hydrogen fosters the circular economy by putting the disposal costs down and creates a new route on renewable hydrogen generation.