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Objective. To systematically evaluate the efficacy and safety of pembrolizumab (PD-1/PD-L inhibitor) and adjuvant chemotherapy to treat NSCLC and provide evidence-based reference for clinical use. Methods. By searching the Cochrane Library, EMBASE, PubMed, and Web of Science, according to the inclusion criteria, literature selection, data extraction, and quality evaluation were carried out for the included literature. The I2 test was used to evaluate heterogeneity between studies, and the meta-analysis was performed using RevMan 5.3 software provided by Cochrane. Results. Finally, 14 relevant documents meeting the standards were included. It is a statistical difference in one-year survival rate [ OR = 1.50 , 95% CI (1.28, 1.76), P < 0.00001 , I 2 = 0 %, Z = 4.99 ]; overall response rate[OR =1.57, 95% CI (1.29, 1.90), P < 0.00001 , I 2 = 0 %, Z = 4.58 ]; progression-free survival [ OR = 2.99 , 95% CI (2.29, 3.91), P < 0.00001 , I 2 = 26 %, Z = 8.00 ]; and overall survival [ OR = 1.38 , 95% CI (1.07, 1.78), P = 0.01 , I 2 = 46 %, Z = 2.50 ] and reduces the incidence of adverse drug reactions [ OR = 2.54 , 95% CI (1.99, 3.25), P < 0.00001 , I 2 = 69 %, Z = 7.43 ]. Conclusion. Pembrolizumab adjuvant chemotherapy is effective in the treatment of advanced NSCLC, but attention should be paid to the occurrence of adverse reactions in clinical. Due to the limitations of the methodology included in the study, this conclusion required more validation of large-sample RCT.

Sea water resources are extensive and can be used to extinguish fires, but their corrosiveness is a major problem. Using the method of electrochemical workstation, the electrochemical corrosion behavior of aluminum sheet in artificial sea water solution and silica-coated artificial seawater was studied; by analyzing the surface morphology, polarization curve and electrochemical impedance spectroscopy, the electrochemical corrosion behavior of aluminum sheets under different immersion times and different immersion media is obtained. The conclusion is that the coating of nanosilica powder has a certain corrosion protection effect on artificial seawater.

Fluid catalytic cracking (FCC) slurry is a by-product of petrochemical industry rich in aromatics. In this paper, the effect of FCC slurry on the physical properties of SBS modified bitumen was investigated by softening point, penetration, ductility and low temperature flexibility test. The influence of FCC slurry on the compatibility of SBS modified bitumen was evaluated by fluorescence microscope and segregation test. The results show that FCC slurry improves the softening point, penetration, ductility and low temperature flexibility of SBS modified bitumen. Fluorescence microscope showed that FCC slurry promotes the dispersion of SBS in bitumen, which is conducive to the formation of network crosslinking structure of SBS modified bitumen. The segregation test indicated that the compatibility of SBS with bitumen was improved with the content of FCC slurry increasing.

With the exploration and development of various oil and gas wells, the underground pressures in new and old blocks are becoming more and more complex, and the risk of well control is increasing. Well control training is an effective way to improve the well control quality and well control safety awareness of operators. Based on the HTC VIVE Pro development kit and high-performance VR workstation, this paper combines virtual reality technology to realize 3D dynamic well control simulation of oil and gas wells. The system can realize the three-level well control operation training and assessment, corresponding data flow, and the function of predicting and simulating the well control risk of the new exploration point based on the actual well data. So complex well control operations and limited field training become simplification, visualization, contextualization and operation. It can be used for drilling engineering and oil well operation technicians, on-site engineering supervision reference and training, and can also be used for drilling and analysis of emergency plans.

At present, with the rapid development of the national economy, China’s demand for energy is becoming stronger. It is particularly important to develop an efficient and environmentally friendly fire extinguishing agent to ensure energy security. As a new type of environmentally friendly fire extinguishing agent, dry water has the advantages of both water mist and dry powder fire extinguishing agent. The core-shell structure of dry water fire extinguishing agent makes it have fluidity and dispersibility similar to powder fire extinguishing agent, while maintaining extremely high-water content, making it of great application value in the field of fire extinguishing agents. In this paper, the preparation, physical and chemical properties of dry water extinguishing agents and the fire extinguishing performance of Class B fires are studied, based on the existing fire extinguishing theories and experimental results, the fire extinguishing mechanism of dry water extinguishing agents is discussed.

A cup burner was used to measure the minimum fire extinguishing concentrations for methane extinguishment by fine water mist with additives/air co-flow diffusion flames based on ultrasonic atomization. The comparison of the minimum fire extinguishing concentrations of pure and fine water mist revealed that the existence of additives could change the fire extinguishing efficiency of pure water, with their improvement effect ranked as KCl > KH 2 PO 4 > NH 4 H 2 PO 4 . A flame thermal balance equation was established, and a model for predicting the minimum fire extinguishing concentrations of different fire extinguishing agents was developed. A differential scanning calorimeter was used to measure solution heat capacity, and the physicochemical properties of different liquid extinguishers were predicted. When the mass fractions of the additives equated to 2%, the chemical fire extinguishing effect was superior. The influence of additives on fire extinguishing efficiency mainly involves an increase in chemical actions and a reduction in the competition between the evaporative capacities of pure water.

This study analyzed the effects of both water mist and water mist with different additives on cooling of cooking oils during fire extinguishment. The sizes of water mist drops with different additives were measured using a split-type laser particle analyzer. Full-scale extinguishment–cooling experiments using different fire extinguishing agents and oil temperatures were also conducted. The boiling over layer formed during the cooling of cooking oil using water mist could significantly enhance the cooling rate. Moreover, the expanding rate of this boiling over layer is related to oil temperature and water mass in oils. Although additives reduce water evaporation and hinder oil cooling, such additives also inhibit the expansion of the boiling over layer, thereby reducing the risk of secondary damage caused by abundant oil overflow after the fire extinguishment.

Cooking oil fires which happened in the kitchen or hotel have become quite popular over the last decades. Compare to other types of fires, cooking oil fires are very difficult to extinguish. Both foam and powder can effectively extinguish the flames over the oil surface but they are very difficult to cool the oil below its auto-ignition temperature and to prevent it from re-ignition due to their limited cooling capacity. Moreover, water mist with additives may be applied to provide additional improvements in terms of suppression effectiveness and temperature control of cooking oil fires. The present work establishes a series of home-scale experiments to study extinguishing mechanisms and effectiveness of pure water and water mist with additives against cooking oil fires. The thermal transient within the test chamber has been evaluated during the fire development as the main quantitative parameter. Results showed that water mist is shown to be efficient in cooking oil fires control, especially endowed with the chosen additives which demonstrated that water mist with additives would extinguish cooking oil fires through physical and chemical mechanisms. Furthermore, the change in fire extinguishing efficiency differs for different additives and mass fractions of the additives.

BACKGROUND Apoptosis is mediated by the endoplasmic reticulum (ER) stress pathway, mitochondrial pathway, and death receptor. Data herein suggested an inhibitory effect of marchantin M on tumor formation in nude mice as well as the impact on CHOP and GRP78 expression. MATERIAL AND METHODS The role of marchantin M on proliferation and apoptosis of DU145 cells were measured by MTT and flow cytometry, respectively. Western blot was applied to detect the expression of GRP78 and CHOP. The mice received abdominal injection at 1 time/2 d and 2 ml/time. Tumor volume was measured every 6 days. The mice were euthanatized 30 days after marchantin injection and tumor weight was measured. Cell apoptosis was determined by TUNEL. The expressions of CHOP and GRP78 were detected by immunohistochemistry. RESULTS Tumor size and weight in marchantin groups were significantly lower than in the control group (A, B) (P

Using MATLAB for development tools,we has developed a set of end mills CNC grinding programming system by analysis the end mills grinding craft ,research on cutter location trajectory calculation and post-processing technology. Meanwhile, build a five-axis tool grinder grinding simulation processing by VERICUT(a kind of CNC machining simulation software), through the edge grinding simulation , we confirm the cutter location trajectory and the NC code is errorless.

The key system which requiring very high levels of reliability often use redundancy to enhance reliability index, e.g. tolerant system. During system operation, tolerant system monitors system state and reconfigures it to realize continuous working with system drawback. Considering the inevitable errors in system online test and the performance degradation, an estimation method for both system reliability and performance is proposed in this paper. Through analyzing the important fault mode in tolerant system, establishing the system reliability model based on k-out-n:G system description, and then considering the imperfect tests and corresponding performance degradation in these process, the reliability and performance evaluation method is given, moreover, the engineering operation flow of this method was established for it. An aircrafts rudder system is taken as an example for engineering application, which shows that this approach is feasible and effective.

Cd1−x Zn x S (x = 0, 0.1, 0.2, 0.3, 1.0) thin films have been grown successfully on soda-lime glass substrates by chemical bath deposition technique as a very promising buffer layer material for optoelectronic device applications. The composition, structural properties, surface morphology, and optical properties of Cd1−x Zn x S thin films were characterized by energy dispersive analysis of X-ray technique (EDAX), X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV–Vis spectrophotometer techniques, respectively. The annealed films were observed to possess the deficient sulfur composition. The results of XRD show that the Cd1−x Zn x S (x = 0.1) thin film annealed at 450 °C forms hexagonal (wurtzite) structure with lattice parameters a = 0.408814 nm, c = 0.666059 nm, and its average grain size is 24.9902 nm. The diffraction peaks become strong with the increasing annealing temperatures. The surface of Cd1−x Zn x S (x = 0.1) thin film annealed at 450 °C is uninterrupted and homogenous as compared to other temperatures. From optical properties, it is observed that the presence of small amount of Zn results in marked changes in the optical band gap of CdS. The band gaps of the Cd1−x Zn x S thin films vary from 2.42 to 3.51 eV as composition varies from x = 0.0 to 1.0. The optical studies in figs reveal that Cd1−x Zn x S thin film annealed at 450 °C shows a high transmittance as a direct-gap semiconductor. The calculated band gap (E g) of the film is about 2.56 eV annealed at 450 °C. This is in close agreement with the reported value (2.49 eV) of Cd0.9Zn0.1S film. Compared to the E g value (2.42 eV) of CdS, the increased E g value is due to the entrance of the element of zinc.

Animals and humans share similar mechanisms of pain detection and similar brain areas involved in pain processing. Also, they show similar pain behaviors, such as reflexed sensation to nociceptive stimuli. Pain is often described in sensory discrimination (algosity) and affective motivation (unpleasantness) dimensions. Both basic and clinical findings indicate that individuals with chronic pain usually suffer more from pain-associated affective disturbances than from the actual pain sensations per se. Although the neural systems responsible for the sensory component of pain have been studied extensively, the neural mechanisms underlying negative affective component are not well understood. This is partly due to the relative paucity of animal paradigms for reliable examination of each component of pain. In humans, the experience of pain and suffering can be reported by language, while in animals, pain can only be inferred through physical and behavioral reactions. Animal behaviors, cognitive psychology and functional brain imaging have made it possible to assess pain affection and pain memory in animals. Animals subjected to either neuropathic injury or inflammatory insult display significant conditioned place aversion to a pain-paired environment in behaviors. The present review aims to summarize the common methods of affective unpleasantness assessment in rats.

A titania layer with ordered nanostructures is expected to be of high photocatalytic activity due mainly to its high specific surface area. In the present work, large-area films with ordered titania nanorods were deposited on titanium substrates through a solution approach. The nanorods, with the phase composition of a mixture of anatase and rutile, grew on top of a condensed anatase interlayer along mainly the rutile [001]-axis. The photocatalytic activity was evaluated by decomposing rhodamine B in water and compared with the general sol-gel derived titania films and a commercial DP-25 titania coating. It is found that the as-deposited titania nanorods exhibited extremely high initial photocatalytic activity but declined to a poor value after the consumption of beneficial oxidative peroxo complexes coordinated to Ti(IV). A subsequent thermal treatment eliminated such complexes but at the same time improved the crystallinity of the titania nanorods. The photocatalytic activity of the thermally treated titania nanorods was stable and significantly higher than that of the sol-gel derived film and commercial DP-25 coating.

Well-crystallized anatase thin films were prepared through direct oxidation of metallic titanium with 30 mass% hydrogen peroxide solution at 80 ◦ C for 5 h, followed by soaking in distilled water at 80 ◦ C for 3 days. The photodegradation of a dye solution, rhodamine B (RB), assisted by such deposited anatase films was studied. It was found that the well-crystallized anatase thin films induced complete degradation of RB in water with an initial concentration of less than 0.02 mM after 4–5 h of illumination under a 450 W high-pressure mercury lamp. The RB decayed directly to colorless end products of water and mineral acids. However, when the photocatalytic activity of the anatase films decreased after several repeated uses, an N-de-ethylation process producing rhodamine as an intermediate was evident during the photocatalytic degradation of RB. © 2004 Elsevier B.V. All rights reserved.

In female, inadequate iron supply is a highly prevalent problem that often leads to iron-deficiency anemia. This study aimed to understand the effects of pregnancy and lactation on iron metabolism. Rats with different days of gestation and lactation were used to determine the variations in iron stores and serum iron level and the changes in expression of iron metabolism-related proteins, including ferritin, ferroportin 1 (FPN1), ceruloplasmin (Cp), divalent metal transporter 1 (DMT1), transferrin receptor 1 (TfR1), and the major iron-regulatory molecule—hepcidin. We found that iron stores decline dramatically at late-pregnancy period, and the low iron store status persists throughout the lactation period. The significantly increased FPN1 level in small intestine facilitates digestive iron absorption, which maintains the serum iron concentration at a near-normal level to meet the increase of iron requirements. Moreover, a significant decrease of hepcidin expression is observed during late-pregnancy and early-lactation stages, suggesting the important regulatory role that hepcidin plays in iron metabolism during pregnancy and lactation. These results are fundamental to the understanding of iron homeostasis during pregnancy and lactation and may provide experimental bases for future studies to identify key molecules expressed during these special periods that regulate the expression of hepcidin, to eventually improve the iron-deficiency status.