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Lithofacies prediction can facilitate the search for hydrocarbon reservoirs and is, therefore, crucial for seismic exploration. We proposed a new approach for lithofacies prediction based on stochastic simulation of pseudo-wells. First, we performed a pseudo-well simulation using a continuous-time Markov chain (CTMC), which can accurately describe geological deposition and can be created using logging, core or geological data. We used the CTMC to randomly generate many pseudo-wells with different lithofacies columns. The corresponding reservoir and elasticity parameters for these lithofacies columns were determined using the Monte Carlo random sampling method. Second, we used seismic modeling and seismic matching to predict the lithofacies. We applied the elastic parameters for each pseudo-well to calculate the reflection coefficients and performed seismic modeling to generate synthetic seismic data. Thereafter, we used a weighted matching function based on prior geological constraints to match the synthetic seismic data with actual seismic data. We predicted the lithofacies based on numerous pseudo-wells with the best fit and tested the influencing factors of the method using model data. Finally, we applied this method to the field data, and the predicted lithofacies agreed well with the wells. Compared to conventional methods, the proposed method can use prior information in the log and the geology data, and detects thin layers better.

Accurate digital mapping of farmland soil organic carbon (SOC) contributes to sustainable agricultural development and climate change mitigation. Farmland landscape pattern has changed greatly under anthropogenic influence, which should be considered an environmental variable to characterize the impact of human activities on SOC. In this study, we verified the feasibility of integrating landscape patterns in SOC prediction on Lower Liaohe Plain. Specifically, ten variables (climate, topographic, and landscape pattern variables) were selected for prediction with Random Forest (RF) and Support Vector Machines (SVMs). The effectiveness of landscape metrics was verified by establishing different variable combinations: (1) natural variables, and (2) natural and landscape pattern variables. The results confirmed that landscape variables improved mapping accuracy compared with natural variables. R2 of RF and SVM increased by 20.63% and 20.75%, respectively. RF performed better than SVM with smaller prediction error. Ranking of importance of variables showed that temperature and precipitation were the most important variables. The Aggregation Index (AI) contributed more than elevation, becoming the most important landscape variable. The Mean Contiguity Index (CONTIG-MN) and Landscape Contagion Index (CONTAG) also contributed more than other topographic variables. We conclude that landscape patterns can improve mapping accuracy and support SOC sequestration by optimizing farmland landscape management policies.

Traditional lung-protective ventilation strategies (LPVS) are currently used to reduce the incidence of postoperative pulmonary complications (PPCs), including low tidal volume (VT), positive end-expiratory pressure (PEEP), low inspiratory plateau pressure (Pplat), permissive hypercapnia, and recruitment maneuver (RM). However, a meta-analysis showed that high driving pressure was closely associated with the incidence of PPCs, but not with PEEP or VT, which led to the driving pressure-guided ventilation strategy. Some studies have proved that the driving pressure-guided ventilation strategy is superior to the traditional LPVS in reducing the incidence of PPCs. The purpose of this review is to present the current research progress and application of driving pressure-guided ventilation strategy.

With the rapid growth of livestock, they produce more and more waste, causing severe environmental damage. Biochar as a composting additive has several advantages, including improved performance and humification processes, increased enzyme activity, and reduced nitrogen (N) losses. To investigate the effect of biochar addition on compost quality and enzyme activity, we composted cattle manure with different biochar measures (2%, 5%, and 10%) and different types (rice husk and rice straw) of biochar. The results showed that adding biochar to the aerobic compost of cow manure effectively accelerated the temperature rise of the compost, decreased the total carbon (C) content of the compost, and the total N content increased from the mesophilic phase to the decaying period. The C-to-N compost showed a decreasing trend. The 5% rice husk biochar and 2% rice straw biochar treatments more effectively reduced the N loss during composting and played a better role in N fixation. The addition of rice husk biochar more effectively increased the urease activities compared with the addition of rice straw biochar. Adding 5% rice husk biochar increased the peroxidase and polyphenol oxidase activities by 78% and 38%, respectively. Therefore, adding 5% rice husk biochar effectively improved compost quality and enzyme activities and reduced N loss in the aerobic composting process of cattle manure for optimal compost production.

Mechanical ventilation can induce lung injury and exacerbate brain injury due to lung-brain interaction. The current study sought to investigate the mechanism of lung-brain interaction induced by mechanical ventilation and offer theoretical insight into the management of ventilator-induced brain injury. The experimental mice were assigned into the spontaneously breathing group and the mechanical ventilation group and injected with dopamine (DA) receptor antagonist haloperidol or P2Y1 receptor antagonist MRS2279 before ventilation. In vitro assay was conducted using lung epithelial cells MLE-12 hippocampal neuron cells and HT-22. Mouse recognition function and lung injury were examined. The condition and concentration of neurons in the hippocampus were observed. The levels of several inflammatory factors, DA, adenosine triphosphate (ATP), P2Y1R, and dysbindin-1 were detected. Mechanical ventilation induced lung and brain injury in mice, manifested in increased inflammatory factors in the bronchoalveolar lavage fluid and hippocampus, prolonged escape latency, and swimming distance and time in the target quadrant with a weakened concentration of neurons in the hippocampus. Our results presented elevated ATP and P2Y1R expressions in the mechanically ventilated mice and stretched MLE-12 cells. The mechanically ventilated mice and P2Y1 receptor activator MRS2365-treated HT-22 cells presented with elevated levels of DA and dysbindin-1. Inactivation of P2Y1 receptor in the hippocampus or blockage of DA receptor alleviated brain injury induced by mechanical ventilation in mice. To conclude, the current study elicited that lung injury induced by mechanical ventilation exacerbated brain injury in mice by increasing ATP production, activating the P2Y1 receptor, and thus promoting DA release.

The involvement of Dexmedetomidine (Dex) has been indicated in postoperative cognitive dysfunction (POCD), while the mechanism is not well characterized. This study estimated the mechanism of Dex in POCD. Rats were anesthetized with sevoflurane (SEV) to evoke POCD and then subjected to Morris water maze test to detect the cognitive and behavioral function. Then, the damage of hippocampus and cortex, and apoptosis and activity of neurons were examined. Microarray analysis was performed to screen out the differentially expressed microRNAs (miRs) in rats after Dex treatment. The cognitive and behavioral functions and neuronal activity of rats were detected after miR-129 antagomir injection. The target of miR-129 was predicted. The levels of TLR4 and NF-κB p65 in hippocampus and cortex were measured. Dex treatment alleviated SEV-induced behavior and cognitive impairments in rats, promoted neuronal activity and hindered neuronal apoptosis. After treatment with Dex, miR-129 expression was elevated in brain tissues, and the neuroprotection of Dex on POCD rats was partially annulled after injection of miR-129 antagomir. Furthermore, miR-129 targeted TLR4 and prevented the phosphorylation of NF-κB p65. In summary, Dex ameliorated SEV-induced POCD by elevating miR-129 and inhibiting TLR4 and NF-κB p65 phosphorylation. This study may shed new lights on POCD treatment.

High concentrations of redox substances in the solution may cause severe electrode potential drift, resulting in the inaccuracy of in situ measurements. Sulfide anion, a highly reductive substance, is the killer of all metal oxide electrodes because of its small size and strong surface activity. We first proposed to use SPEEK (SP) with silica-stabilized imidazole-type ionic liquid (ImIL) to fabricate a composite film (SP/SiO

Background This study explored the comparison of the thermal insulation effect of incubator to infusion thermometer in laparoscopic hysterectomy. Methods We assigned 75 patients enrolled in the study randomly to three groups: Group A: Used warming blanket; group B: Used warming blanket and infusion thermometer; group C: Used warming blanket and incubator. The nasopharyngeal temperature at different time points during the operation served as the primary outcome. Results The nasopharyngeal temperature of the infusion heating group was significantly higher than that of the incubator group 60 min from the beginning of surgery (T3): 36.10 ± 0.20 vs 35.81 ± 0.20 (PPPPP = 0.004) and the incubator group: 24 ± 4 vs 22 ± 4 (P = 0.035). Conclusion Warming blanket (38 °C) combined infusion thermometer (37 °C) provides better perioperative thermal insulation. Hospitals without an infusion thermometer can opt for an incubator as a substitute. Trial registration This trial was registered with ChiCTR2000039162, 20 October 2020.

Background: The purpose of this study was to compare the thermal insulation effect of incubator and infusion thermometer in laparoscopic hysterectomy.Methods: 75 patients were enrolled and were assigned randomly to three groups: group A used warming blanket, group B used warming blanket and infusion thermometer, group C used warming blanket and incubator. The primary outcome was nasopharyngeal temperature at different time points during the operation.Results: The nasopharyngeal temperature of the infusion heating group was significantly higher than that of the incubator group 60min at the beginning of surgery(T3):36.10±0.20 vs 35.81±0.20(P＜0.001)；90min at the beginning of surgery(T4):36.35±0.20 vs 35.85±0.17(P＜0.001),and the incubator group was significantly higher than that of the control group 60min at the beginning of surgery(T3):35.81±0.20 vs 35.62±0.18(P＜0.001);90min at the beginning of surgery(T4):35.85±0.17 vs 35.60±0.17(P＜0.001).The wake-up time of the control group was significantly higher than that of the infusion heating group: 23.88±3.86 vs 20.56±3.80(P=0.004), and the incubator group:23.88±3.86 vs 21.52±4.02(P=0.035).Conclusion: Warming blanket (38°C) combined infusion thermometer (37°C) provides better perioperative thermal insulation, and in hospitals without infusion thermometer, an incubator can be used as a substitute.Trial registration: This trial was registered with http://www.chictr.org.cn/index.aspx,ChiCTR2000039162,20 October 2020.

pH is a fundamental parameter in understanding the chemical processes in many fields. Based on the strong oxidative characteristic of the molten lithium carbonate (Li2CO3), an advanced iridium oxide electrode preparation approach is developed by adding sodium peroxide (Na2O2) powder into a Li2CO3 melt in a semi-closed/closed reactor at a high temperature to increase the regional peroxide (O22−) ion concentration in the iridium-melt interface. The iridium oxide film (IROF) of prepared electrodes has a dense and uniform surface with small and cone-shaped particles. Open-circuit tests show that electrodes exhibit a near-Nernstian pH response with good linearity, fast response, high stability (a slight periodic fluctuation of potential change with standard deviation

The precipitation and dissolution processes of CaCO3 are essential to the marine carbon cycle and are relevant to climate research. Nevertheless, one of the nagging questions is why the precipitation of CaCO 3 rarely occurs without the help of biological activity even in the surface seawater , where the calcite saturation state (Ω, expressed as the ratio of the calcium and carbonate ion concentration product to the stoichiometric solubility constant of calcite) is up to 5, but commonly takes place in hard-water lakes, springs and the low-salinity zone (practical salinity estuaries . Studies have found that Mg 2+ plays a significant role in inhibiting all aspects of CaCO3 precipitation, namely crystal formation, solubility, and precipitation rate. However, whether the presence of Mg2+ in seawater is sufficient to inhibit CaCO3 precipitation has not been clearly stated, and the specific inhibitory role of Mg2+ in CaCO3 precipitation still requires clarification. In this study, we used four different seed materials to induce CaCO3 precipitation in artificial seawater of four Mg:Ca ratios and examined the crystal morphologies of the resulting precipitates using scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). We found that Mg 2+ inhibits the precipitation at the first stage of nucleation, which drastically increases the difficulty of calcite nucleation. At a seawater Mg:Ca ratio of 5.2, aragonite preferentially nucleates instead of calcite. Among the tested materials, only calcite and aragonite seeds exhibit marked catalysis of CaCO 3 precipitation, indicating that not all the particles in natural seawater can catalyze CaCO3 precipitation. Our results demonstrate while the precipitation of CaCO3 is inhibited by Mg2+ at all stages, the inhibition at the nucleation stage is the main reason massive spontaneous CaCO3 precipitation does not occur under the surface seawater conditions, supporting the notion that the incorporation of foreign ions such as Mg2+ increases the surface energy and the solubility of the overgrowth or cluster, and thus inhibits CaCO 3 precipitation.

Phaeodactylum tricornutum (P. tricornutum) is a model and unique species of marine diatom with high lipid content and rapid growth. Alkaline flocculation is considered as a potential method to concentrate microalgae biomass, which is critical for large-scale cultivation and harvesting. In this study, we developed an effective approach to the traditional alkaline flocculation method by utilizing the auto-flocculation ability of P. tricornutum. We studied the performance and mechanism of auto-flocculation by comparing the inorganic and organic processes, assisted by scanning electron microscope (SEM), X-ray diffraction (XRD), and zeta potential. And we found that the role of algae growth in mediating Mg(OH)2 precipitation was not only to help increase pH but also adsorb divalent cations around the cell wall, which thus made algae cells the seeds facilitating Mg(OH)2 precipitation. We thus discovered a new pathway named “wrapping-sedimentation” during the auto-flocculation process, besides the charge neutralization and sweeping mechanisms. Through the auto-alkaline flocculation method, higher harvesting efficiency with at least a 2/3 reduction in alkali addition could be achieved.

Aiming at the problems of the various types of digital input and output modules in the anti-harsh hardened computer, the lack of a dedicated test system and the incomplete testing, a dedicated digital input and output test system with a wide test range was designed. The system is based on single-chip microcomputer and FPGA and can provide 64 channels of digital output (0∼30V adjustable), 64-channel digital or voltage value input test, 64 channels of switch-type digital signal, and the status of the tested module can be read in real time through the host computer software. The digital input and output modules can solve the current situation of incomplete functional testing, and the test results are accurate, stable, and reliable, with a compact structure and multiple test channels.

This paper proposes a remote sensing image zero-watermark algorithm based on DFT, which can be used to protect the rights and interests of digital image copyright owners. First, the high frequency part after DCT transformation is binarized to obtain the characteristic image. Second, block DFT processing the host image. The high frequency part after DFT and the characteristic image are XORed to complete the watermark embedding. In order to test the performance of the watermark, an attack was carried out on the image embedded with the watermark. In order to extract the watermark from the attacked image, the high-frequency part of the data extracted from the attacked image is XORed again with the result of the first XOR. Compare the extracted watermark with the embedded watermark, and calculate its NC value. Most of the NC values are close to 1, indicating that the algorithm is robust. In addition, the PSNR values of the attacked image and the original image are also calculated. The experimental results show that the watermark obtained by the algorithm in this paper has strong invisibility and robustness.

Hydrogen peroxide (H2O2) has been reported to be used for the illegal treatment of fishery products in order to obtain “fake” freshness. Residues of H2O2 in food may be of toxicology concern. In this study, a nonenzymatic sensor was developed based on Fe@PCN-224 metal–organic frameworks wrapped by Nafion to detect H2O2 concentration. The hybrid structure of Fe@PCN-224 was fabricated by incorporated free FeIII ions into the center of PCN-224, which was ultra-stable due to the strong interactions between Zr6 and the carboxyl group. Scanning electron spectroscopy images exhibited that Nafion sheets crossed together on the surface of Fe@PCN-224 nanoparticles to form a hierarchical and coherent structure for efficient electron transfer. Electrochemical investigations showed that the Fe@PCN-224/Nafion/GCE possessed good linearity from 2 to 13,000 μM (including four orders of magnitude), low detection limits (0.7 μM), high stability in continuous monitoring (current remained nearly stable over 2300 s) and in long-term measurement (current decreased 3.4% for 30 days). The prepared nanohybrid modified electrode was effectively applied to H2O2 detection in three different fishery products. The results were comparable to those measured using photometrical methods. The developed electrochemical method has a great potential in detecting the illegal management of fishery products with H2O2.

In the two states of oil-gas and water-gas, the wave velocity and attenuation coefficient are numerically simulated by double-scale model. The P-wave velocity and attenuation coefficient curves show double-step and double-peak, respectively. With the increase of gas saturation, the velocity step of mesoscopic scale gradually decreases and disappears. The attenuation peak decreases and the characteristic frequency shifts to high frequency until it coincides with the characteristic frequency of the micro-scale. The superposition of the attenuation peak makes the total attenuation peak increase. And there is a great difference in fluid properties when oil, gas and water are mixed in the reservoir, so the double-scale model can better predict the fluid saturation in the reservoir and better monitor the fluid.

Some efficient structure preserving algorithms have been proposed for high precision seismic exploration and detection in recent years. However, feasible artificial boundary conditions to truncate unbounded medium are never discussed in structure preserving seismic modeling. We pay our emphasis on application of perfectly matched layer absorbing boundary condition (PML ABC) to fit the structure preserving algorithms. In the domain of interest, a typical structure preserving algorithm is presented to discretize the conservative dynamic system, while in the PML region, traditional central difference is applied to solve the dissipative system. In the adjacent region of the interior and exterior domains, the temporary values of wave field between two time steps are approximated by interpolation using the present and the updated value of the wave fields in the PML region. A numerical experiment is adopted to demonstrate compatibility of the algorithms and no visible reflections of outgoing waves occur on the edge of interior domain.

To evaluate the 95% effective dose of nalbuphine in patient-controlled intravenous analgesia (PCIA) by the sequential method and compare the analgesia efficacy with the equivalent dose of sufentanil on patients undergoing laparoscopic total hysterectomy.In the first part, we defined a successful analgesia as the highest VAS ≤3 in 24 hours postoperatively. On the contrary, a failed analgesia was the highest VAS3. According to the last patient's outcome, the next patients would be given an increase or decreased dose grade. This process ended up with 9 cross-over points. In the second part, 60 patients undergoing laparoscopic total hysterectomy were selected. They were randomly divided into 2 groups (n = 30 each group): receiving sufentanil 1.78 μg/kg (group S) and nalbuphine 1.78 mg/kg (group N). PCIA pump was given at the end of the operation with 5 mL bonus loading. The total amount of PCIA was 100 mL and programmed to deliver 0.5 mL each time with a lockout interval of 15 minutes and the background infusion amount of 2 mL/h. The VAS score and Ramsay score of were collected after the operation, the number of effective pressing times of PCIA were also recorded. Adverse reactions were documented in detail.The 95% effective dose of nalbuphine in PCIA on patients undergoing laparoscopic total hysterectomy was 1.78 mg/kg. There was no significant difference in VAS between the sufentanil group and the nalbuphine groups (P .05), but the number of the use of PCIA in the group S was more than that in the group N obviously (P.05). The group S has a lower ramsay sedation score than group N at every time point. (P.05). The incidence of nausea and vomiting was not statistically significant differences between two groups in the first 24 hours after colonoscopy (P q .05).Nalbuphine 1.78 mg/kg in PCIA is recommended for the patients undergoing laparoscopic total hysterectomy. And nalbuphine is a reasonable alternative to sufentanil when used in PCIA.

Pyruvate dehydrogenase (PDH) of Escherichia coli is inhibited by NADH. This inhibition is partially reversed by mutational alteration of the dihydrolipoamide dehydrogenase (LPD) component of the PDH complex (E354K or H322Y). Such a mutation in lpd led to a PDH complex that was functional in an anaerobic culture as seen by restoration of anaerobic growth of a pflB, ldhA double mutant of E. coli utilizing a PDH- and alcohol dehydrogenase-dependent homoethanol fermentation pathway. The glutamate at position 354 in LPD was systematically changed to all of the other natural amino acids to evaluate the physiological consequences. These amino acid replacements did not affect the PDH-dependent aerobic growth. With the exception of E354M, all changes also restored PDH-dependent anaerobic growth of and fermentation by an ldhA, pflB double mutant. The PDH complex with an LPD alteration E354G, E354P or E354W had an approximately 20-fold increase in the apparent K(i) for NADH compared with the native complex. The apparent K(m) for pyruvate or NAD(+) for the mutated forms of PDH was not significantly different from that of the native enzyme. A structural model of LPD suggests that the amino acid at position 354 could influence movement of NADH from its binding site to the surface. These results indicate that glutamate at position 354 plays a structural role in establishing the NADH sensitivity of LPD and the PDH complex by restricting movement of the product/substrate NADH, although this amino acid is not directly associated with NAD(H) binding.

Escherichia coli O157:H7 is an intestine-inhabiting bacterium associated with many severe disease outbreaks worldwide. It may enter the soil environment with the excreta of infected animals (including horses, cattle and chickens) and human. Earthworms are able to protect themselves against invading pathogens due to their efficient innate defense system. To better understand the mechanisms earthworms (Eisenia fetida) utilize to defend and eliminate Escherichia coli O157:H7, we examined the changes in the growth rate, as well as antioxidant and antimicrobial functions of earthworms in response to various concentrations of Escherichia coli O157:H7 in an artificial soil. Our results show that earthworms can inhibit the growth of Escherichia coli O157:H7. Upon exposure to Escherichia coli O157:H7 from 0 d to 24 d, coelomic cytolytic factor (CCF) in earthworms is induced, the reactive oxygen species (ROSs) and superoxide dismutase (SOD) are also elevated. Under lower bacterial concentrations (10(5)-10(6)CFU g(-1)), these ROSs can be rapidly scavenged by superoxide dismutase (SOD) to avoid peroxidation damage, but when the bacterial concentrations are high (10(7)-10(8)CFU g(-1)), excess amount of ROSs then cause accumulation of lipid peroxidation molecular malondialdehyde (MDA). In addition, exposure to Escherichia coli O157:H7 can induce the gene expression of antimicrobial peptide lumbricin I in the tissues of the earthworms. In conclusion, antioxidant systems and antimicrobial immune function may play important roles in the defense of the earthworms Eisenia fetida against Escherichia coli O157:H7.