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Photo-selective catalytic reduction of nitric oxide (NO) with methane (CH) over TiO and Pt/TiO photocatalysts was studied at reaction temperatures of 25, 50, and 100 °C. The activity of Pt/TiO in NO reduction was better than that of TiO. Conversion of NO by use of Pt/TiO and UV irradiation was up to 86.4 %. In-situ Fourier-transform infrared spectroscopy was successfully used to monitor the photoreaction process on TiO and Pt/TiO photocatalysts. During irradiation with UV light, bidentate nitrite disappeared and bidentate nitrate, monodentate nitrate, and isocyanate, an important intermediate, were generated. Adsorbed NH was found to be the final product of NO reduction after UV irradiation. We concluded that NO could be effectively reduced by CH under light irradiation at temperatures below 100 °C. A possible reaction mechanism is proposed on the basis of the intermediates and products generated by the photocatalyst under UV light irradiation. [ABSTRACT FROM AUTHOR]

Abstract: The photocatalytic methods for nitrogen oxides removal were recently very intense areas of scientific research. Photo-deNO x processes offer interesting ways for abatement of these harmful gases. This review describes several methods for removing NO by photocatalytic reactions. These methods can be classified into three major groups: photo selective catalytic reduction (photo-SCR), photo-oxidation and photo-decomposition. The application of photocatalysts and photo-processes for NO x abatement in real-scale cases are presented. The fast-growing development of these methods is revealed by the large number of issued patents in photo-deNO x applications. The mechanism of NO creation and the traditional methods (primary and secondary) of NO x removal are summarized and discussed. A cooperative system that combines the traditional (thermal) process and a photo-process is then proposed for improving NO x removal efficiency. [Copyright &y& Elsevier]

Abstract: Photocatalytic reduction of nitric oxide was studied on a PtO x PdO y /TiO2-coated monolith photoreactor using propane as the reducing agent. The performance of NO reduction was compared under three reaction conditions including NO/propane, NO/propane/O2 and NO/propane/H2O at three reaction temperatures, 25, 70 and 120°C. The NO/propane system showed the best performance of near 90% conversion at 25°C. The NO conversion decreased slightly as temperature increased in NO/propane system, however, NO/propane/O2 and NO/propane/H2O systems showed an opposite trend. Oxygen and water significantly inhibited the reduction of NO because oxygen competed with NO as oxidant, and water interfered the adsorption of both NO and propane. TiO2 became super-hydrophilic under UV-light irradiation thus the catalyst surface was easily covered by water in moisture condition. By increasing the reaction temperature, water tended to desorb from the catalyst surface thus released more active sites for NO photoreduction. An in situ FTIR was also performed to study the intermediate species of the NO/propane and NO/propane/O2 systems under UV-light irradiation. The results indicated that NO went through both oxidation and reduction with C3H8 on PtO x PdO y /TiO2. The reaction path of NO might change with increasing temperature. [Copyright &y& Elsevier]

The rapid cultivation of partial nitritation/ANAMMOX （PN/A） granular sludge in a continuous-flow mode is one of the key technologies for efficient biological nitrogen removal in domestic wastewater treatment. Compared with that in PN/A granular sludge, PN granular sludge demonstrates a shorter incubation period and suitability for batch culture. It is also a good carrier for enriching ANAMMOX （AMX） bacteria. In this study, we established a continuous-flow autotrophic nitrogen removal process in three continuously stirred tank reactors （CSTR） （R1-R3） by hybrid-inoculating PN/A and PN granular sludge at the mass ratios of 3∶1, 1∶1, and 1∶3, respectively. By implementing high ammonium nitrogen loading and short hydraulic retention time, continuous autotrophic nitrogen removal processes were successfully started up in the three CSTRs. The results showed that compared with that of R1 and R2, R3 had a longer start-up time but a similar steady-state nitrogen removal performance. The total nitrogen removal load of R3 could be more than 2.6 kg·（m 3 ·d） -1 . Intriguingly, the inoculated PN granular sludge served as a precursor for PN/A granular sludge cultivation. This approach facilitated the enrichment of anaerobic ammonia-oxidizing bacteria （AMX） by introducing abundant ammonium-oxidizing bacteria （AOB） and nitrite nitrogen substrates into the CSTR. According to the results of high-throughput sequencing, the microbial abundance and diversity of the mature granules in R1-R3 were significantly higher than those of the inoculation sludge. AOB （genus Nitrosomonas ）, AMX （genera Candidatus Kuenenia and Candidatus Brocadia ）, and symbiotic heterotrophs, such as Chloroflexi, Bacteroidetes, and Chlorobi, drove the autotrophic nitrogen removal process and maintained the stability of the granular structure. In summary, a novel start-up strategy of hybrid-inoculating granular sludge was provided for a continuous-flow autotrophic nitrogen removal in engineering application.

The aim of this study was to determine whether long non-coding RNA PVT1 can participate in the regulation of cardiac hypertrophy. A C57BL/6 mouse cardiac hypertrophic model was established using transverse aortic constriction (TAC). The animals subjected to sham operation were used as controls. Transcripts of PVT1 were analyzed in hearts of model and sham control groups after TAC for 4 weeks using quantitative real-time PCR (qRT-PCR). Additionally, to investigate whether PVT1 was involved in cardiac hypertrophy, 1 μM angiotensin II (Ang II) was used to induce hypertrophy and PVT1 siRNA was performed in the cultured neonatal mouse cardiac cardiomyocytes. Cell size was measured by cell surface area and total protein content analyses in response to Ang II treatment. Moreover, some hypertrophic markers including atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP), and beta-myosin heavy chain (β-MHC) were also quantified using qRT-PCR. As a result, PVT1 was up-regulated by 2.5-fold (P<0.05) in hypertrophic hearts after TAC for 4 weeks as compared to sham group. In addition, siRNA of endogenous PVT1 in cardiomyocytes significantly reduced (P<0.05) Ang II-induced increase of cell size in terms of cell surface area (by 5.6-fold) and total protein content (by 23.0%). PVT1 siRNA also obviously attenuated Ang II-induced ANP and β-MHC expression by 40.9% and 41.5%, respectively (P<0.05), but had no effect on BNP mRNA expression. Our results demonstrated that PVT1 was essential for the maintenance of cell size of cardiomyocytes and might play a role in the regulation of cardiac hypertrophy.

Objective: To evaluate clinical outcome of suture anchors in strengthening both acromioclavicular and coracoclavicular ligaments in the surgical treatment of acromioclavicular joint dislocation., Methods: Twenty-eight patients with acute traumatic Rockwood III, IV and V dislocations of the acromioclavicular joint surgically treated at our institute between October 2010 and January 2012 were recruited.All patients underwent open reduction combined with suture anchors. Function was evaluated using the Constant- Murley shoulder score. Clinical and radiographic shoulder ratings were evaluated using Taft criteria at 3, 6 and 12 months., Results: Two cases with fixation loosening were not included in final statistical analysis. Other patients obtained full joint reposition on immediate postoperative radiographs. Follow-up was performed with an average of 15.6 months (range, 12-19). After early range of motion exercises, 96.2% of the patients (25/26) could abduct and elevate their shoulders more than 90 degrees within postoperative 3 months. There was no infection. Average Constant-Murley score was 96.3 points (range, 94-100) and mean Taft shoulder rating was 10.7 points (range, 8-12) at 12 months., Conclusion: The suture anchor is a relatively simple technique and can avoid screw removal which is helpful in reconstructing both acromioclavicular and coracoclavicular ligaments in acute traumatic acromioclavicular joint dislocation.

Objective: To observe and analyze the intraoperative state of calcaneal fractures, and summarize the law of displacement after calcaneal fractures, so as to guide fracture reduction and fixation., Methods: From March 2002 to March 2009, among 572 patients with calcaneal fractures, 427 patients were male and 145 patients were female, ranging in age from 17 to 73 years, averaged 37 years. The patients were injured from falling or road accidents, and all the patients were closed fracture. The 189 patients with complete clinical data were treated with reduction and fixation through the lateral approach after observation of displacement type of the fractures., Results: Among 189 patients,the fractures were found at the lower part of the articular surface in all patients, which was hillock point of calcaneus; the fractures were found at the Gissans Corner in 134 patients, and the type include cross-sectional fracture or oblique fracture; the fractures were found at calcaneal tubercle in 118 patients, and the fractures were divided into two parts from top to bottom; the fractures were found at the distal part of calcaneus only in 67 patients., Conclusion: Calcaneal fractures show clear law of dislocation. Preoperative and intra-operative detailed analysis and evaluation, as well as reduction and fixation according to certain sequences can insure to get better operative effects.

Objective: To retrospective analysis operating procedures and results of calcaneal fractures treated with plate fixation, identify problems and propose measures to reduce surgical complications., Methods: From June 2008 to April 2009, 156 patients were reviewed, including 121 males and 35 females, ranging in age from 18 to 59 years, with an average of 41 years. Thirty-two patients had bilateral calcaneal fractures. Twenty-three patients were surgically treated on both calcaneus at the same time. Total 179 calcaneus were treated with operation. The operation records of all patients were analyzed in order to find the problems and deficiencies., Results: Among 179 calcaneal fractures, 31 feet (17.3%) had postoperative wound problems: wound infection and non-healing were found in 26 feet (14.5%), skin flap necrosis in 5 feet (2.8%). There were a lot of problems of plate internal fixation for the treatment of calcaneal fractures, including operation design, operative technique, as well as fracture reduction and fixation., Conclusion: The following methods are the only way to avoid operative complications for the treatment of calcaneal fractures: improved surgical technique, minimally invasive operation, simple and effective internal fixation.