Bacterial community activity and dynamics in the biofilm of an experimental hybrid wetland system treating greywater

Abstract

The objectives of this study were to determine the biofilm microbial activity and bacterial community structure and successions in greywater treatment filters and to relate the treatment efficiency to the bacterial community parameters. This 10-month study was performed in a newly established experimental system for domestic greywater treatment that consisted of three parallel vertical flow filters (VFs) followed by a horizontal flow filter (HF). A rapid increase in the bacterial community abundance occurred during the first 85 days of filter operations, followed by a short-term decrease and the stabilization of the 16S rRNA gene copy numbers at average levels of 1.2 × 10⁹ and 3.2 × 10⁸ copies/g dw in VFs and HF, respectively, until the end of the experiment. The dominant bacterial phyla and genera differed between the VFs and HF. The temporal variation in the bacterial community structure was primarily related to the species replacement, and it was significantly affected by the influent organic carbon and nitrogen compounds in the VFs and the ammonia and organic carbon in the HF filters. Despite the differences in the community structure and assembly mechanisms, the temporal dynamics of the bacterial community showed high congruence between the filter types. The treatment efficiency was related to the biofilm bacterial community diversity and abundance and the abundance of certain bacterial genera in the VF filters. The results suggest that the dominant pathway of nitrogen removal by greywater treatment VFs occurs via coupled heterotrophic nitrification and denitrification, while the contribution of aerobic denitrification is temporally variable in these filters.

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Nerve transfer of the anterior interosseous nerve to the thenar branch of the median nerve – an anatomical and histological analysis

Nerve transfer has become a vital method in the reconstruction of hand function. Reconstructing the motor function to the thenar musculature has proven to be difficult and is rarely satisfactory following direct anatomic repair. Aim of this investigation was to describe the anatomic results obtained by transferring the anterior interosseous nerve to the thenar branch of the median nerve and analyze the histomorphometric results.

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Commentary on JPRAS-D-18-00185: The Use of Laser Speckle Contrast Imaging to predict flap necrosis - an experimental study in a porcine flap model Article

The authors need to be congratulated for their fine study on the use of Laser Speckle Contrast Imaging (LSCI) to predict flap necrosis in an experimental setting with a porcine pedicled flap model. LSCI has been repeatedly described for perfusion analysis in flap surgery. There has always been a demand to simplify or optimize intra- and postoperative flap monitoring, especially in free flap surgery. However, the individual techniques to postoperatively monitor free flaps vary considerably. In former studies from the early 1990ies with questionnaires ninety percent of microsurgeons reported to routinely use monitoring devices, with external and laser doppler having achieved greatest popularity.

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Complications after lower body contouring surgery due to massive weight loss unaffected by weight loss method

Body contouring surgery following massive weight loss positively affects patient quality of life. However, the procedure is prone to complications. Here, we stratified complications time-wise. Furthermore, we examined whether the weight loss method — bariatric surgery or lifestyle changes — affected the frequency or severity of complications. In this single-centre retrospective analysis, we included 158 massive weight loss patients undergoing body contouring surgery between 2009 and 2015. We recorded 96 complications in 80 patients, with an overall rate of 51%.

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Reply to: “Updated guidelines on complex regional pain syndrome in adults”

We read with interest the article by Dr. Henderson "Updated guidelines on complex regional pain syndrome in adults." 1 The article provides an elegant summary of the Royal College of Physicians (RCP) current guidelines in the diagnosis and treatment of complex regional pain syndrome (CRPS) and recommends surgical intervention for the treatment of Type 2 CRPS (i.e. CRPS with a recognized nerve injury). However, it fails to identify the timing of such interventions. This is important considering the emerging paradigm shift in concepts of nerve pain, specifically 'centralization' of pain in neuroma patients with delayed presentations.

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Four corner fusion: Comparing outcomes of conventional K-wire-, locking plate-, and retrograde headless compression screw fixation

Several operative approaches and various implants for osseous fixation have been described to achieve four-corner fusion of the wrist. Given the discordance and to aid in further standardizing the technique, this study directly compares the outcomes of K-wire-, fusion-plate, and headless retrograde compressive screw-fixation to achieve four-corner arthrodesis.

https://ift.tt/2LjtjuN

Adipose-derived stem cell research, worry and hope

In the wake of call for retractions of papers from Harvard University heart stem cell research lab, the public concerns had been raised about stem cell researches, including adipose-derived stem cells (ADSCs).

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