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Reservoir permeability is an important parameter for reservoir characterization and the estimation of current and future production from hydrocarbon reservoirs. Logging data is an important means of evaluating the continuous permeability curve of the whole well section. Nuclear magnetic resonance logging measurement results are less affected by lithology and have obvious advantages in interpreting permeability. The Coates model, SDR model, and other complex mathematical equations used in NMR logging may achieve a precise approximation of the permeability values. However, the empirical parameters in those models often need to be determined according to the nuclear magnetic resonance experiment, which is time-consuming and expensive. Machine learning, as an efficient data mining method, has been increasingly applied to logging interpretation. XGBoost algorithm is applied to the permeability interpretation of carbonate reservoirs. Based on the actual logging interpretation data, with the proportion of different pore components and the logarithmic mean value of T2 in the NMR logging interpretation results as the input variables, a regression prediction model is established through XGBoost algorithm to predict the permeability curve, and the optimization of various parameters in XGBoost algorithm is discussed. The determination coefficient is utilized to check the overall fitting between measured permeability versus predicted ones. It is found that XGBoost algorithm achieved overall better performance than the traditional models.

Hypoxia-inducible factor 1α (HIF-1α) plays a critical role in the apoptotic process during cardiac ischaemia/reperfusion (I/R) injury. This study aimed to investigate whether post-treatment with dexmedetomidine (DEX) could protect against I/R-induced cardiac apoptosis in vivo and in vitro via regulating HIF-1α signalling pathway. Rat myocardial I/R was induced by occluding the left anterior descending artery for 30 minutes followed by 6-hours reperfusion, and cardiomyocyte hypoxia/reoxygenation (H/R) was induced by oxygen-glucose deprivation for 6 hours followed by 3-hours reoxygenation. Dexmedetomidine administration at the beginning of reperfusion or reoxygenation attenuated I/R-induced myocardial injury or H/R-induced cell death, alleviated mitochondrial dysfunction, reduced the number of apoptotic cardiomyocytes, inhibited the activation of HIF-1α and modulated the expressions of apoptosis-related proteins including BCL-2, BAX, BNIP3, cleaved caspase-3 and cleaved PARP. Conversely, the HIF-1α prolyl hydroxylase-2 inhibitor IOX2 partly blocked DEX-mediated cardioprotection both in vivo and in vitro. Mechanistically, DEX down-regulated HIF-1α expression at the post-transcriptional level and inhibited the transcriptional activation of the target gene BNIP3. Post-treatment with DEX protects against cardiac I/R injury in vivo and H/R injury in vitro. These effects are, at least in part, mediated via the inhibition of cell apoptosis by targeting HIF-1α signalling.

BackgroundRight ventricular function (RVF) is an independent predictor of prognosis for patients undergoing aortic valve replacement: transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR). The effect of transfemoral aortic valve replacement (TF-TAVR) on RVF is uncertain. We aimed to perform a meta-analysis of the effect of TF-TAVR on RVF in patients with aortic stenosis (AS) and compare the effect of TF-TAVR with SAVR.MethodsWe searched relevant studies from PubMed, Embase, Cochrane Library databases, and Web of Science. Furthermore, two reviewers (Wang AQ and Cao YS) extracted all relevant data, which were then double checked by another two reviewers (Zhang M and Qi GM). We used the forest plot to present results. Tricuspid annular plane systolic excursion (TAPSE) was the primary outcome.ResultsThis meta-analysis included 11 studies. There were 353 patients who underwent TF-TAVR, and 358 patients who were subjected to SAVR. There was no significant difference in TAPSE at 1 week and 6 months as well as right ventricular ejection fraction (RVEF) at

The synthesis of ionic olefin linked threedimensional covalent organic frameworks (3D COFs) is challenging because of the difficulties in forming stable carbon-carbon double bonds. Here, the authors report a general synthesis of an ionic sp2 carbon linked COFs and demonstrate selective capture of ReO4 − ions.

Abstract Background Adequate sedation is essential for pediatric patients undergoing 3Tesla (T) magnetic resonance imaging (MRI). Using propofol alone is associated with patient arousing and adverse airway events. This study aimed to assess esketamine vs dexmedetomidine adjunct to propofol sedation for pediatric 3 T MRI. Methods In this randomized, double-blind, controlled trial, 114 pediatric patients aged between 6 months and 8 years were randomly assigned, in a 1:1 ratio, to the esketamine–propofol group or the dexmedetomidine–propofol group. Sedation was provided with esketamine or dexmedetomidine in combination with propofol titration. The primary outcome was the total dose of propofol. Secondary outcomes included propofol infusion dose, adverse events, time to emergence from sedation, and time to discharge from recovery room. Results A total of 111 patients completed this study (56 in the esketamine–propofol group and 55 in the dexmedetomidine–propofol group). All MRI procedures were successfully performed under sedation. The total median (IQR) dose of propofol was significantly lower in the esketamine–propofol group (159.8 [121.7, 245.2] μg/kg/min) than that in the dexmedetomidine–propofol group (219.3 [188.6, 314.8] μg/kg/min) (difference in medians [95% CI] = − 66.9 [− 87.8 to − 43.0] μg/kg/min, P

Abstract The primary function of heat shock transcription factor (HSF) in the heat shock response is to activate the transcription of genes encoding heat shock proteins (HSPs). The phloem-feeding insect Bemisia tabaci (Gennadius) is an important pest of cotton, vegetables and ornamentals that transmits several plant viruses and causes enormous agricultural losses. In this study, the gene encoding HSF (Bthsf1) was characterized in MED B. tabaci. The full-length cDNA encoded a protein of 652 amino acids with an isoelectric point of 5.55. The BtHSF1 deduced amino acid sequence showed strong similarity to HSF in other insects. Expression analyses using quantitative real-time PCR indicated that Bthsf1 was significantly up-regulated in B. tabaci adults and pupae during thermal stress. Although Bthsf1 was induced by both hot and cold stress, the amplitude of expression was greater in the former. Bthsf1 had distinct, significant differences in expression pattern during different duration of high but not low temperature stress. Oral ingestion of dsBthsf1 repressed the expression of Bthsf1 and four heat shock proteins (Bthsp90, Bthsp70-3, Bthsp20 and Bthsp19.5) in MED B. tabaci during hot and cold stress. In conclusion, our results show that Bthsf1 is differentially expressed during high and low temperature stress and regulates the transcription of multiple hsps in MED B. tabaci.

Uranium is one of the most important strategic resources for the development of the nuclear industry, but its unintended release has created potential environmental and health risks. It is highly desired to explore new methods that enable concurrent uranium monitoring and recovery for environmental protection and sustainable development of the nuclear industry. Here, for the first time, an imidazole fluorescent covalent organic framework (named PyTT-Tp) with ultrastable skeleton and open nanopore channel is synthesized by condensing ammonium acetate, 1,3,5-triformylphloroglucinol and pyrene-4,5,9,10-tetrone. By precisely tailoring complexing ligands, PyTT-Tp shows an excellent uranium recovery capacity of 941.27 mg g−1 and reached equilibrium within 60 min, which can be attributed to dense selective uranium binding sites on the highly accessible open skeleton. In addition, due to the signal amplification of the pyrene-imidazole skeleton, it has an ultra-low detection limit of 4.92 nM UO22+ and an ultra-fast response time (2 s) suitable for on-site monitoring the uranium content of the extracted water. By modulating target complexing ligands, this approach can be extended to the monitoring and recovery of other strategic nuclides.

The supersonic parachute plays an important role in the descent and landing of Mars missions. Next-generation supersonic parachutes, such as disksail parachutes, are alternatives to disk-gap-band (DGB) parachutes. Disksail parachutes have larger porous gaps and smaller porous seams on the canopy surface than DGB parachutes. To date, the influence mechanism of porous seams or gaps and their locations on the performance of supersonic parachute systems in Martian atmospheric conditions remains unclear. In this study, different canopy models with seams and gaps based on NASA’s supersonic disksail parachutes were designed, and the aerodynamic characteristics of such geometric porosity models were studied numerically. For seam-only models, the drag coefficient of the parachute decreases when the position of the seam is close to the middle of the canopy. When the seam is close to the mouth of the canopy, the pressure difference between the inner and outer surface of the canopy becomes small, reducing the risk of tearing the canopy. For gap-only models, the drag coefficient of the middle gap model is higher, while the lateral force stability of the top gap model is better. The results show that the addition of a seam can improve the drag performance of the top gap model and improve the lateral stability of the canopy with the middle gap. This study provides some theoretical references for designing the porosity of parachutes under different requirements for Mars exploration missions in the future.

This meta-analysis aimed to analyze and compare the efficacy and safety of remifentanil and dexmedetomidine applied respectively for controlled hypotension under general anesthesia. We searched the Cochrane Library, PubMed, EMBASE, Web of Science, CNKI, SinoMed, Wanfang, and VIP databases, as well as dissertations and conference papers, to obtain randomized controlled trials comparing remifentanil and dexmedetomidine applied respectively for controlled hypotension before August 23, 2021. The primary outcomes included hemodynamic profiles, surgical field score, and blood loss. Extubation time, sedation and pain score at the PACU, and perioperative adverse events were the secondary outcomes. Nine randomized controlled trials with 543 patients (272 in the dexmedetomidine group and 271 in the remifentanil group) were eventually included. This meta-analysis indicated no significant difference between dexmedetomidine and remifentanil in terms of surgical field score, blood loss, minimum values of mean arterial pressure (MD 0.24 with 95% CI [-1.65, 2.13], P = 0.80, I2 = 66%) and heart rate (MD 0.42 [-1.33, 2.17], P = 0.64, I2 = 40%), sedation scores at the PACU (MD -0.09 [-0.69, 0.50], P = 0.76, I2 = 92%), and incidence of bradycardia (OR 2.24 [0.70, 7.15], P = 0.17, I2 = 0%). Compared with remifentanil, dexmedetomidine as the controlled hypotensive agent showed a lower visual analogue score at the PACU (MD -1.01 [-1.25, -0.77], P