Photoredox-Catalyzed Sequential Decarboxylative/Defluorinative Aminoalkylation of CF3-Alkenes with N-Arylglycines.

A photoredox-catalyzed sequential decarboxylative/defluorinative aminoalkylation of CF3-alkenes with N-arylglycines is described. This metal-free and redox-neutral protocol provided efficient access to the monofluoroalkenyl-1,5-diamines in good yields with excellent functional group compatibility. Mechanistic studies revealed that the reaction proceeds via a radical pathway with the gem-difluoroalkenyl amine as an intermediate.

Rational design of S-scheme AgI/ZrTiO4-x heterojunctions for remarkably boosted norfloxacin degradation.

Emerging S-scheme heterojunction photocatalysts endowed with efficient charge separation and strong redox capacity have stimulated wide interests in dealing with environmental issues nowadays. In this work, we firstly fabricated the oxygen vacancy modified ZrTiO4-x nanocrystals, which was further combined with AgI to build the defective S-scheme AgI/ZrTiO4-x heterojunctions for visible-light photocatalytic norfloxacin degradation. The synthesized ZrTiO4-x nanocrystals and AgI/ZrTiO4-x heterojunctions displayed remarkably boosted norfloxacin degradation performance under visible-light irradiation. The reaction rate constant of the optimized AgI/ZrTiO4-x-5% heterojunction is as high as 0.01419 min-1, which is approximately 43.35 times that of AgI and 7.93 times that of ZrTiO4-x nanocrystals, and far superior to those of commercial TiO2 and commercial ZrO2. The high-performance photocatalytic norfloxacin degradation could be mainly attributed to the formation of S-scheme charge transfer pathways and oxygen vacancy defects. More significantly, AgI/ZrTiO4-x could also realize the effective photo-decomposition of other emerging pollutants. Finally, the visible-light photocatalytic performance and photocatalysis mechanism were investigated.

A simple strategy to effectively produce d-lactate in crude glycerol-utilizing Escherichia coli.

BACKGROUND: Fed-batch fermentation has been conventionally implemented for the production of lactic acid with a high titer and high productivity. However, its operation needs a complicated control which increases the production cost. RESULTS: This issue was addressed by simplifying the production scheme. Escherichia coli was manipulated for its glycerol dissimilation and d-lactate synthesis pathways and then subjected to adaptive evolution under high crude glycerol. Batch fermentation in the two-stage mode was performed by controlling the dissolved oxygen (DO), and the evolved strain deprived of poxB enabled production of 100 g/L d-lactate with productivity of 1.85 g/L/h. To increase productivity, the producer strain was further evolved to improve its growth rate on crude glycerol. The fermentation was performed to undergo the aerobic growth with low substrate, followed by the anaerobic production with high substrate. Moreover, the intracellular redox of the strain was balanced by fulfillment of the anaerobic respiratory chain with nitrate reduction. Without controlling the DO, the microbial fermentation resulted in the homofermentative production of d-lactate (ca. 0.97 g/g) with a titer of 115 g/L and productivity of 3.29 g/L/h. CONCLUSIONS: The proposed fermentation strategy achieves the highest yield based on crude glycerol and a comparable titer and productivity as compared to the approach by fed-batch fermentation. It holds a promise to sustain the continued development of the crude glycerol-based biorefinery.

Monitoring bladder compliance using end filling detrusor pressure: Clinical results and related factors.

OBJECTIVE: To assess the clinical significance of low compliance bladder (LCB) in women with lower urinary tract symptoms. MATERIALS AND METHODS: Medical records of 1490 women undergoing videourodynamic studies (VUSs) were reviewed. Comprehensive medical histories, physical examinations, bladder diaries, and results of multichannel VUS were analyzed. This study adopted an end filling detrusor pressure (EFP) greater than 20 cmH2O to define LCB. RESULTS: Among the study patients (n = 1490), 9.1% were diagnosed with LCB using a cutoff value of 17.5 cmH2O, which had a sensitivity and specificity of 89% and 92.7%, respectively. Results of multivariate analysis indicated that age (p = 0.005), maximum cystometric capacity (MCC; p = 0.002), detrusor overactivity (DO; p = 0.001), pelvic organ prolapse (POP; p = 0.018), recurrent urinary tract infection (p = 0.001), and radical abdominal hysterectomy (RAH; p < 0.001) as independent prognostic factors. Furthermore, our study results indicate that the MCC, urinary tract infection, and a history of RAH have a positive correlation with LCB, whereas, age, POP, and DO have a negative correlation with LCB. CONCLUSION: Our idea using EFP (≥17.5 cmH2O) for screening women with LCB is feasible for clinical use.