Iron‐based heterogeneous catalysts, which were generally prepared by pyrolysis of iron complexes on supports at elevated temperature, were found to be capable of catalyzing the transfer hydrogenation ...of furfural (FF) to furfuryl alcohol (FFA). The effects of metal precursor, nitrogen precursor, pyrolysis temperature, and support on catalytic performance were examined thoroughly, and a comprehensive study of the reaction parameters was also performed. The highest selectivity of FFA reached 83.0 % with a FF conversion of 91.6 % under the optimal reaction condition. Catalyst characterization suggested that iron cations coordinated by pyridinic nitrogen functionalities were responsible for the enhanced catalytic activity. The iron catalyst could be recycled without significant loss of catalytic activity for five runs, and the destruction of the nitrogen–iron species, the presence of crystallized Fe2O3 phase, and the pore structure change were the main reasons for catalyst deactivation.
FF to FFA with Fe: Efficient catalytic transfer hydrogenation of furfural (FF) to furfuryl alcohol (FFA) over heterogeneous iron catalysts is demonstrated for the first time. Iron cations coordinated by pyridinic nitrogen functionalities on the carbon support are possibly responsible for the enhanced catalytic activity. This paves the way for achieving biomass conversion through heterogeneous iron catalysis.
•Build an experimental platform of intermediate cycle aeroengine thermal management system.•Explore the influences of working condition on the systematic heat transportation.•Apply heat current ...method and artificial neural network builds simulation model.
With the increment of Mach number, the heat dissipation load of aeroengine increases significantly. Systematic thermal management has become an urgent problem to be solved. The intermediate cycle system is one of the widely used thermal management solutions. This paper builds an experiment platform of thermal management system of aeroengine including intermediate cycle to explore the influence of working condition on the systematic heat transportation. Water is selected as the working medium in the experiment. The experiment results show all the temperatures of working medium decrease with the flow rate increment of working medium in fuel oil circuit. The temperature of working medium flowing to the afterburner increases with the temperature increment of lube oil circuit1 and 2. But only the temperature of working medium flowing to the main combustor increases while the temperatures of lube oil circuit1 increase. At last, using heat current method and flow resistance model builds the systematic simulation model. The relative errors between the simulation and experimental values are all less than 5%. The simulation results show all the temperatures of working medium increase with the increment of fuel oil circuit temperature. The working medium temperature flowing to the afterburner and lube oil circuit2 increases with the flow rate increment of lube oil circuit3. It reveals the heat transfer principle of the intermediate circulation thermal system under different working states and provides a powerful guidance for the systematic analysis and design.
•Build an experiment of aero-engine thermal management system including intermediate cycle.•Apply heat current method and artificial neural network to construct optimization model.•Heat dissipation ...rate of system increases by 8.6% after optimization.•Total thermal conductance of system decreases by 36.6% after optimization.
Reliability and efficiency of the aero-engine thermal management system (ATMS) is of great importance to ensure the required working condition. Conventional methods on modeling ATMS are complex and difficult to solve for optimizing the whole system under multiple conditions. This study combines the heat current method and artificial neural network (ANN) to develop the optimization models with the objectives of maximum heat transfer rate and minimum thermal conductivity respectively. The ATMS experimental platform with intermediate cycle using water as the simulated medium is constructed to verify the optimization reliability. After optimization, the maximum heat transfer rate of ATMS is increased from 7740 W to 8402 W by 8.6%. The minimum thermal conductivity decreases from 1628 W/K to 1032 W/K by 36.6% comparing with the initial working condition. While considering the conditions of artificial control on the fuel oil side, the optimal thermal conductivity decreases from 1628 W/K to 1101 W/K by 32.3%. The optimal findings provide powerful guidance for improving the heat dissipation and reducing weight of the aircraft.
Dysregulation of pre-mRNA alternative splicing (AS) is closely associated with cancers. However, the relationships between the AS and classic oncogenes/tumor suppressors are largely unknown. Here we ...show that the deletion of tumor suppressor PTEN alters pre-mRNA splicing in a phosphatase-independent manner, and identify 262 PTEN-regulated AS events in 293T cells by RNA sequencing, which are associated with significant worse outcome of cancer patients. Based on these findings, we report that nuclear PTEN interacts with the splicing machinery, spliceosome, to regulate its assembly and pre-mRNA splicing. We also identify a new exon 2b in GOLGA2 transcript and the exon exclusion contributes to PTEN knockdown-induced tumorigenesis by promoting dramatic Golgi extension and secretion, and PTEN depletion significantly sensitizes cancer cells to secretion inhibitors brefeldin A and golgicide A. Our results suggest that Golgi secretion inhibitors alone or in combination with PI3K/Akt kinase inhibitors may be therapeutically useful for PTEN-deficient cancers.
This work provided the first example of selective hydrodeoxygenation of 5‐hydroxymethylfurfural (HMF) to 2,5‐dimethylfuran (DMF) over heterogeneous Fe catalysts. A catalyst prepared by the pyrolysis ...of an Fe‐phenanthroline complex on activated carbon at 800 °C was demonstrated to be the most active heterogeneous Fe catalyst. Under the optimal reaction conditions, complete conversion of HMF was achieved with 86.2 % selectivity to DMF. The reaction pathway was investigated thoroughly, and the hydrogenation of the C=O bond in HMF was demonstrated to be the rate‐determining step during the hydrodeoxygenation, which could be accelerated greatly by using alcohol solvents as additional H‐donors. The excellent stability of the Fe catalyst, which was probably a result of the well‐preserved active species and the pore structure of the Fe catalyst in the presence of H2, was demonstrated in batch and continuous flow fixed‐bed reactors.
Selective and stable Fe: Selective catalytic hydrodeoxygenation of 5‐hydroxymethylfurfural to 2,5‐dimethylfuran over heterogeneous Fe catalysts is demonstrated in batch and continuous flow fixed‐bed reactors. The Fe catalyst exhibited excellent stability, which is probably a result of the well‐preserved active species and the pore structure of the Fe catalyst in the presence of H2.
To evaluate the "flow void" diameter in patients with pregnancy-related diseases with and without uterine AVMs and assess the diagnostic performance of unenhanced MRI for uterine AVMs. From May 2014 ...to April 2019, 79 patients with pregnancy-related diseases were included, including 36 with and 43 without uterine AVMs confirmed by DSA. On MRI, the diameter of the most prominent "flow void" (hereinafter referred to as fv-D) was measured and compared between patients with and without uterine AVMs. The diagnostic performance of fv-D was estimated with receiver operating characteristic curves. The "flow void" sign was observed in patients with and without uterine AVMs (P > 0.05). The fv-D was significantly larger in patients with uterine AVMs in the myometrium and parametrium than in patients without uterine AVMs (P < 0.0001). The fv-D achieved a reliable diagnostic performance in the myometrium (sensitivity 80.6%, specificity 60.5%, negative predictive value 78.8%, positive predictive value 63%, AUC 0.727, cut-off: > 1.33 mm) and parametrium (sensitivity 97.2%, specificity 67.4%, negative predictive value 96.7%, positive predictive value 71.4%, AUC 0.881, cut-off > 2.6 mm). On MRI, fv-D could diagnose uterine AVMs. The fv-D had a much higher diagnostic efficiency in the parametrium than in the myometrium. The parametrium fv-D greatly improved the diagnostic sensitivity and provides a more accurate, noninvasive method of investigating possible uterine AVMs.
To assess the efficacy and safety of abdominal aortic (AA) balloon occlusion versus internal iliac arteries (IIA) balloon occlusion in patients with placenta accreta spectrum (PAS) disorders.
...Databases of Embase, PubMed, Web of Science and Cochrane Library were systematically searched from inception to May 2020. The relevant literature was screened and the quality was assessed. RevMan software 5.3 was used to analyze the data.
Six studies involving 239 patients in AA occlusion and 281 patients in IIA occlusion were included. The results demonstrated that the intraoperative hemorrhage volume (MD − 410.61 ml, 95% CI -779.74 to −41.47 ml, p < 0.001), balloon dilatation duration (MD -5.34 min, 95% CI -9.91 to −0.77 min, p = 0.02) and fetus radiation dose (MD-20.81 mGy, 95% CI -31.84 to −9.78 mGy, p < 0.001) were significantly less in AA occlusion compared to IIA occlusion. There was no significant difference in the rate of lower extremity thrombosis between AA occlusion and IIA occlusion (OR 0.21, 95% CI 0.02 to 2.21, p = 0.19); similarly, no significant differences were found in blood transfusion volume (MD −344.50 ml, 95% CI -735.74 to 46.74 ml, p = 0.08), the rate of hysterectomy (OR 0.99, 95% CI 0.22 to 4.44, p = 0.99) and other outcome variables.
The available data demonstrated AA occlusion was more effective in reducing intraoperative hemorrhage volume and fetus radiation dose compared with IIA occlusion in patients with PAS disorders. Larger studies or randomized controlled trials are needed to further assert this evidence.
•Endovascular intervention in abnormal placentation deliveries is effective in reducing blood loss.•Endovascular intervention did not result in longer operative time or hospital stay.•Prophylactic balloon occlusion of the abdominal aorta is superior to other modalities.
Background and Objectives: Attentional bias (AB) for addictive substances is a feature of attention found in individuals with substance misuse or diagnosed with substance use disorders. When AB ...exists, the attention of the addicted individual may be quickly oriented to cues related to the addictive substance or be maintained on these cues for a longer time. AB toward opioids was found in Western samples of smokers with chronic noncancer pain. The level of AB was dose-responsive. However, similar studies in the Taiwanese population are lacking. This study compared the patterns of AB for opioid analgesics in Taiwanese participants with chronic noncancer pain to that of individuals without pain. This study aimed to investigate if AB toward opioids is presented in Taiwanese heavy smokers who are on long-term opioid therapy for pain control. Materials and Methods: Participants were grouped into chronic noncancer pain smokers, chronic pain nonsmokers, and smokers without pain, according to smoking habits and whether or not on long-term opioid therapy for pain control. Each participant completed demographic questionnaires, mood scales, and the opioid-related visual probe task. Differences in AB among the groups were compared using a three-way analysis of covariance controlling for daily cigarette consumption. Results: Chronic noncancer pain smokers (n = 17) and chronic pain nonsmokers (n = 16) displayed more severe levels of depression, anxiety, and pain, compared to smokers without pain (n = 28). Only did chronic pain nonsmokers show significant AB for opioid cues that were displayed for a short time. Analysis on reaction time found that smokers without pain consistently responded faster to the tasks. No difference in reaction time was found between the pain groups. Conclusions: The current study did not fully replicate findings from studies that were based in Western countries. Formulary availability and regulatory limitations might have affected patient’s perception of prescription opioids in Taiwan. However, chronic pain nonsmokers exhibited initial orientation toward opioid-related cues when daily cigarette consumption was accounted for. According to previous research, this AB for shortly displayed opioid cues can be associated with the expectation of pain relief. The current finding also indicated general psychomotor retardation in individuals who were on long-term use of opioids.
Background and Objectives: Local anesthetics administered via epidural catheters have evolved from intermittent top-ups to simultaneous administration of continuous epidural infusion (CEI) and ...patient-controlled epidural analgesia (PCEA) using the same device. The latest programmed intermittent epidural bolus (PIEB) model is believed to create a wider and more even distribution of analgesia inside the epidural space. The switch from CEI + PCEA to PIEB + PCEA in our department began in 2018; however, we received conflicting feedback regarding workload from the quality assurance team. This study aimed to investigate the benefits and drawbacks of this conversion, including the differences in acute pain service (APS) staff workload, maternal satisfaction, side effects, and complications before and after the changeover. Materials and Methods: Items from the APS records included total delivery time, average local anesthetic dosage, and the formerly mentioned items. The incidence of side effects, the association between the duration of delivery and total dosage, and hourly medication usage in the time subgroups of the CEI and PIEB groups were compared. The staff workload incurred from rescue bolus injection, catheter adjustment, and dosage adjustment was also analyzed. Results: The final analysis included 214 and 272 cases of CEI + PCEA and PIEB + PCEA for labor analgesia, respectively. The total amount of medication and average hourly dosage were significantly lower in the PIEB + PCEA group. The incidences of dosage change, manual bolus, extra visits per patient, and lidocaine use for rescue bolus were greater in the PIEB + PCEA group, indicating an increased staff workload. However, the two groups did not differ in CS rates, labor time, maternal satisfaction, and side effects. Conclusions: This study revealed that while PIEB + PCEA maintained the advantage of decreasing total drug doses, it inadvertently increased the staff burden. Increased workload might be a consideration in clinical settings when choosing between different methods of PCEA.
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