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A pilot-scale reactor treating domestic sewage was operated to promote anaerobic digestion and denitrification using endogenous electron donors. While 55 % of organic matter was removed, nitrogen and sulfur showed a different dynamics during the operation. Pyrosequencing analysis clarified this behavior revealing that specific microbial communities inhabited the anaerobic (47.05 % of OTUs) and anoxic (31.39 % of OTUs) chambers. Analysis of 16S rRNA gene partial sequences obtained through pyrosequencing revealed a total of 1727 OTUs clustered at a 3 % distance cutoff. In the anaerobic chamber, microbial community was comprised of fermentative, syntrophic and sulfate-reducing bacteria. The majority of sequences were related to Aminobacterium and Syntrophorhabdus. In the anoxic chamber, the majority of sequences were related to mixotrophic and strictly autotrophic denitrifiers Arcobacter and Sulfuricurvum, respectively, both involved in sulfur-driven denitrification. These results show that pyrosequencing was a powerful tool to investigate the microbial panorama of a complex system, providing new insights to the improvement of the system.  相似文献   
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The reproductive biology of Psammobatis bergi was investigated based on 92 males and 136 females skates taken from the coastal bottom trawl fishery at Puerto Quequén, Argentina. The relationship between total body mass and total length (TL) was not significantly different between sexes, but females were heavier than males. Minimum length at maturity in males was 451 mm TL with a length ratio of 74%, whereas females were 415 mm TL with a length ratio of 74%. TL at which 50% of males were mature was 457.6 mm (75.6% of the largest male) and for females was 441.6 mm (79.1% of the largest female). The results indicate a continuous reproductive cycle during the year, with a maximum number of females carrying egg cases in warmer seasons.  相似文献   
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To assess the validity and reliability of the mechanomyogram (MMG) as a tool to investigate the fatigue-induced changes in the muscle during relaxation, the torque and MMG signals from the gastrocnemius medialis muscle of 23 participants were recorded during tetanic electrically-elicited contractions before and immediately after fatigue, as well as at min 2 and 7 of recovery. The peak torque (pT), contraction time (CT) and relaxation time (RT), and the acceleration of force development (d2RFD) and relaxation (d2RFR) were calculated. The slope and τ of force relaxation were also determined. MMG peak-to-peak was assessed during contraction (MMG p–p) and relaxation (R-MMG p–p). After fatigue, pT, d2RFD, d2RFR, slope, MMG p–p and R-MMG p–p decreased significantly, while CT, RT and τ increased (P < 0.05 for all comparisons), remaining altered throughout the entire recovery period. R-MMG p–p correlated with pT, MMG p–p, slope, τ and d2RFR both before and after fatigue. Reliability measurements always ranged from high to very high. In conclusion, MMG may represent a valid and reliable index to monitor the fatigue-induced changes in muscle mechanical behavior, and could be therefore considered an effective alternative to the force signal, also during relaxation.  相似文献   
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This study evaluated the neutralization breadth in dually infected (DI) HIV-1 long-term non-progressor elite controller patients (LTNP-EC) using a representative minipanel of 6 viruses from 5 different subtypes. Our results showed an improved neutralization breadth in DI LTNP-EC patients when compared with matched LTNP single-infected patients. The role of viral diversity in neutralization was estimated with the Shannon Entropy and the p-distance in viral quasispecies. We found a positive correlation between neutralization breadth and diversity within the viral quasispecies. This correlation could explain why a group of LTNP-EC patients developed a broad neutralizing response despite having undetectable levels of viremia.  相似文献   
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Objective

Rathke’s cleft cysts (RCCs) are quite uncommon sellar lesions that can extend or even arise in the suprasellar area. The purpose of this study is to evaluate the effectiveness of both standard and extended endoscopic endonasal approaches in the management of different located RCCs.

Methods

We retrospectively analyzed a series of 29 patients (9 males, 20 females) complaining of a RCC, who underwent a standard or an extended endoscopic transsphenoidal approach at the Division of Neurosurgery, Department of Neurosciences and Reproductive and Odontostomatological Sciences, of the Università degli Studi di Napoli "Federico II”. Data regarding patients’ demographics, clinical evaluation, cyst characteristics, surgical treatments, complications and outcomes were extracted from our electronic database (Filemaker Pro 11, File Maker Inc., Santa Clara, California, USA).

Results

A standard transsphenoidal approach was used in 19 cases, while the extended variation of the approach in 10 cases (5 purely suprasellar and 5 intra-suprasellar RCC). Cysts contents was fully drained in all the 29 cases, whilst a gross total removal, that accounts on the complete cyst wall removal, was achieved in an overall 55,1% of patients (16/29), specifically 36,8% (7/19) that received standard approach and 90% (9/10) of those that underwent to extended approach. We reported a 56.2% of recovery from headache, 38.5% of complete recovery and 53.8% of improvement from visual field defect and an overall 46.7% of improvement of the endocrine functions. Postoperative permanent DI rate was 10.3%, overall post-operative CSF leak rate 6.9%; recurrence/regrowth occurred in 4 patients (4/29, 13.8%), but only one required a second surgery.

Conclusion

The endoscopic transsphenoidal approach for the removal of a symptomatic RCC offers several advantages in terms of visualization of the surgical field during both the exposure and removal of the lesion. The “extended” variation of the endoscopic approach provides a direct access to the supradiaphragmatic space, allowing adequate view and room for the safe removal of selected supradiaphragmatic RCCs, regardless of the sellar size (even a not enlarged sella), and provides a higher likelihood of preserving normal pituitary tissue and functions.  相似文献   
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