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In this study, scalable, flame spray synthesis is utilized to develop defective ZnO nanomaterials for the concurrent generation of H2 and CO during electrochemical CO2 reduction reactions (CO2RR). The designed ZnO achieves an H2/CO ratio of ≈1 with a large current density (j) of 40 mA cm?2 during long‐term continuous reaction at a cell voltage of 2.6 V. Through in situ atomic pair distribution function analysis, the remarkable stability of these ZnO structures is explored, addressing the knowledge gap in understanding the dynamics of oxide catalysts during CO2RR. Through optimization of synthesis conditions, ZnO facets are modulated which are shown to affect reaction selectivity, in agreement with theoretical calculations. These findings and insights on synthetic manipulation of active sites in defective metal‐oxides can be used as guidelines to develop active catalysts for syngas production for renewable power‐to‐X to generate a range of fuels and chemicals.  相似文献   
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FOXP3 X-linked gene has crucial roles in the development and function of regulatory T cells. We investigated the association of FOXP3 rs3761548, rs3761549 and rs2294021 single nucleotide polymorphisms (SNPs) with acute lymphoblastic leukemia (ALL) susceptibility and response to therapy. Genotyping was performed in 247 patients and 210 healthy subjects. We observed a higher frequency of rs3761548 A carriers and rs2294021 C carriers (p?<?0.04) in male patients, and lower frequencies of rs3761548 AC genotype (p?=?0.04) and rs2294021 CT genotype (p?=?0.01) in female patients compared to controls. ACC (p?=?0.04) and ATC haplotypes (p?=?0.002) were associated with susceptibility to ALL. There was a significant correlation between the genotypes of rs3761548 and rs2294021 SNPs with event-free survival (EFS) and overall survival (OS). The rs3761548 A genotype in male patients was associated with increased risk of relapse (p?<?0.0001), shorter EFS, increased death rate (p?=?0.002) and shorter OS compared to C genotype (p?=?0.001). Similar significant results were observed for the relation of rs2294021 C genotype with response to therapy in male patients. In females, patients with rs3761548 AC genotype had longer EFS (p?=?0.02) and those with rs2294021 CT had longer EFS and OS (p?<?0.005). According to haplotype analysis, patients carrying ACC or ATC haplotypes had the highest number of WBCs and shorter EFS or OS, and patients with CCT haplotype had the lowest number of WBCs and longer EFS or OS. These results provided evidence for the impact of these polymorphisms on susceptibility and response to therapy in children with ALL.

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The limitation of hot spot cooling in microchips represents an important hurdle for the electronics industry to overcome with coolers yet to exceed the efficiencies required. Nanotechnology‐enabled heat sinks that can be magnetophoretically formed onto the hot spots within a microfluidic environment are presented. CrO2 nanoparticles, which are dynamically chained and docked onto the hot spots, establish tuneable high‐aspect‐ratio nanofins for the heat exchange between these hot spots and the liquid coolant. These nanofins can also be grown and released on demand, absorbing and releasing the heat from the hot spots into the microfluidic system. It is shown that both high aspect ratio and flexibility of the fins have a dramatic effect on increasing the heat sinking efficiency. The system has the potential to offer a practical cooling solution for future electronics.  相似文献   
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ABSTRACT: BACKGROUND: Laparoscopic Gastric Plication (LGP) is a new restrictive bariatric surgery, previously introduced by the author. The aim of this study is to explain the modifications and to present the 12-year experience, regarding early and long term results, complications and cost. METHODS: We used LGP for morbid obesity during the past 12 years. Anterior plication (10 cases), one-row bilateral plication while right gastroepiploic artery included (42 cases), and excluded from the plication (104 cases) and two-row plication (644 cases). The gastric greater curvature was plicated using 2/0 prolen from fundus at the level of diaphragm preserving the His angle to just proximal to the pylorus. The anatomic and functional volume of stomach was 50cc and 25cc respectively in two-row method. Ordered postop visits also included evaluation of weight loss, complications, change of diet and control of exercise. RESULTS: LGP was performed in 800 cases (mean age: 27.5, range: 12 to 65 years, nine under 18). Female to male ratio was 81% to 19% and average BMI was 42.1 (35-59). The mean excess weight loss (EWL) was 70% (40% to 100%) after 24 months and 55% (28% to 100%) after 5 years following surgery. 134 cases (16.7%) did not completed long term follow-up. The average time of follow up was 5 years (1 month to 12 years). 5.5% and 31% of cases complained from weight regain respectively during 4 and 12 years after LGP. The mean time of operation was 72 (49--152) minutes and average hospitalization time was 72 hours (24 hours to 45 days). The cost of operation was 2000 $ less than gastric banding or sleeve and 2500 $ less than gastric bypass. Eight patients out of 800 cases (1%) required reoperation due to complications like: micro perforation, obstruction and vomiting following adhesion of His angle. Other complications included hepatitis pneumonia, self-limiting intra-abdominal bleeding and hypocalcaemia. CONCLUSION: The percentage of EWL in this technique is comparable to other restrictive methods. The technique is safe with 1.6% complication (1% reoperated), and 31% regain during 12 years. The cost of operation is less than the other methods.  相似文献   
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Biotechnology Letters - Tumor suppressor miRNAs, miR-15a and miR-16–1, with high-specificity and oncogenic targeting of Bcl-2, can target tumor tissues. Disadvantages of the clinical...  相似文献   
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Bordetella pertussis produces a cell-invasive adenylate cyclase toxin (CyaA) which is related to the RTX family of pore-forming toxins. Like all RTX toxins, CyaA is synthesised as a protoxin (proCyaA), encoded by the cyaA gene. Activation to the mature cell-invasive toxin involves palmitoylation of lysine 983 and is dependent on co-expression of cyaC. The role of the cyaC gene product in the acylation reaction has not been determined. We have developed an efficient T7 RNA polymerase system for over-expression of cyaA and cyaC separately in Escherichia coli. Each protein accumulated intracellularly in an insoluble form and could be collected by centrifugation of lysed cells. A single-step purification was achieved by extraction of the aggregated material with 8 M urea. Active cell-invasive CyaA was produced in vitro when the proCyaA and CyaC proteins were mixed with a cytosolic extract of either E. coli or B. pertussis. Activation was assumed to occur by an acylation reaction requiring acyl carrier protein (ACP) as cofactor, as the cytosolic factor required for toxin activation was lost if the S100 extract was dialysed before use and the cytosolic factor could be replaced in the in vitro reaction by ACP charged separately in vitro with palmitic acid, as reported previously for activation of the homologous E. coli haemolysin (HIyA). The in vitro activation system may be used to investigate the mechanism of the CyaC-dependent acylation of proCyaA and the effect of variation of the modifying fatty acyl group on target cell specificity and toxic activity of CyaA  相似文献   
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Although dryland ecosystems are the most abundant terrestrial biomes on the Earth, relatively little is known about their microbial diversity and potential metabolic activities. Therefore, the bacterial diversity of the Lut Desert in Iran has been remained largely obscure. In this study, ionizing radiation resistant bacteria from arid Gandom Beryan region was investigated by a culture-dependent method. After exposing the soil and surface sand samples to different periods of dehydration in a desiccator containing silica gel, two nonendospore- forming bacterial isolates were recovered by plating on R2A and TSA agar media and then subjected to a desiccation and ionizing radiation resistance assay. The isolates A2 and B9 were still recovered after 8 weeks in a desiccator containing silica gel and were moderately resistant to gamma radiation with a D10 value between 2 and 4 kGy. Strains A2 and B9 were affiliated with Modestobacter muralis MDVD1T (99.7% similarity) and Maritalea mobilis E6T (97.3% similarity) respectively, using 16S rRNA gene sequence analysis. This is the first report of radiation resistant bacteria which belongs to the genus Maritalea.  相似文献   
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