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Aiming at the problem of autonomous obstacle avoidance of fixed-wing UAVs in a complex, dense and multi-obstacle environment, a path planning algorithm for fixed-wing UAVs based on a safe flight corridor is proposed. The difficulty of avoiding dense obstacles lies in the choice of obstacle circumvention and traversal: although circumvention is safer, the flight cost is greater; although the traversal cost is lower, the safety threat is higher. How to quickly solve the optimal path is the core issue. This paper firstly defines a safe flight corridor innovatively based on the maneuvering characteristics of fixed-wing UAVs and the Dubins curves. By comprehensively considering UAV flight safety and flight costs, an obstacle threat evaluation function is constructed. Secondly, in view of the computational complexity caused by the dense obstacles, an obstacle clustering algorithm based on obstacle density is proposed, and the nonlinear evaluation function in a high dynamic environment is quickly approximated by Monte Carlo sampling method. Finally, simulations verify the effectiveness of the proposed algorithm in solving dense obstacle avoidance for fixed-wing UAVs.

The intermittent sampling repeater jamming (ISRJ) technology is a clever coherent multi-false target jamming technology. New research on ISRJ against different radar processing systems and different radar waveforms has become one of the hotspots in the current radar countermeasures field. In order to further clarify the characteristics of ISRJ and corresponding expanded application prospects, the background and basic principles of ISRJ has been reviewed firstly. Then, the detailed development history of ISRJ has also been outlined and the new ISRJ types were summarized and classified. At last, the expanded application of intermittent sampling in radar detection and other fields was introduced, aiming to provide some reference for experts and scholars. [ABSTRACT FROM AUTHOR]

In the field of biomedicine, two-dimensional (2D) cell lines and animal models have played an important role in the study of cell pathways and drug targets. However, due to species differences between humans and other animals, and the lack of hierarchy, cellular diversity, and cell-cell or cell-matrix interactions, 2D cell lines could not fully reflect what cells actually look like in the human body. Organoids are three-dimensional (3D) in vitro culture models derived from autologous tissue stem cells, which make up for the defects of 2D culture and can simulate the structure and function of real human organs to a certain extent, providing new ideas for disease diagnosis and treatment. Among them, lung organoids (LO) are a typical case studying the development process of human lung and the generation principle of lung diseases. Relevant studies have provided help for the treatment of pulmonary fibrosis, lung cancer, lung injury and other diseases. This paper aims to summarize and analyze the research progress of lung organoids in recent years, and further summarize the application of LO in the diagnosis and treatment of lung diseases. [ABSTRACT FROM AUTHOR]

The effect law of the type, viscosity and content of dust suppressants on the dust emission and physical properties of cement based ceramic tile adhesive were analyzed and compared. The results show that the dust suppressant can better suppress the dust emission of the tile adhesive at lower viscosity, and can better maintain the mechanical properties of ceramic tile adhesive. As the amount of dust suppressant increases, the suppression of dust emission becomes stronger. However, beyond a certain amount, the mechanical properties of the ceramic tile adhesive will be greatly affected, and the optimal amount of dust suppressant is 0.4% ~0.6%. [ABSTRACT FROM AUTHOR]

With polyether monomer (TPEG), acrylic acid (AA), hydroxyl ethyl acrylate (HEA) as the main raw material, the AA and HEA mole ratio given conditions, with methyl allyl sulfonate (SMAS) to replace part of AA, butyl acrylate (BA) replacing part of HEA, a kind of water reducing agent with ultra-long sustained-release type was synthesized under the condition of aqueous solution polymerizationat normal temperature. Through orthogonal test and single factor test, the influence of dosage ratio of each monomer and dropping process on its performance was studied. Meanwhile, IR and GPC were used to characterize its molecular structure. The results showed that the water-reducing agent had the best dispersion effect and maintenance of dispersion effect when the reaction temperature was 28 °C, the acid-ether ratio was 5:1, n (AA):n (HEA) =3 .5:6.5, the replacement rate of SMAS was 7.5%, the replacement rate of BA was 20%, the mixture of small monomers was pre-added by 50% and the A material dropping time 2 h, B material dropping time 2.5 h. [ABSTRACT FROM AUTHOR]

CD226 is an activated receptor on the surface of natural killer (NK) cells. It competes with TIGIT and CD96 to bind to ligands such as CD155 on the surface of tumor cells and mediates the killing function of NK cells. Although TIGIT and CD96 have other binding ligands in the tumor microenvironment, they compete to bind CD115 ligands with higher affinity and inhibit the activity of NK cells, which allows tumor cells to evade killing. Therefore, studying the expression patterns of these three NK cell surface receptors in different tumors and monitoring their binding ability with ligands will help us to explore new tumor treatment strategies. This article reviews the role and mechanism of CD226, TIGIT, CD96 and other NK cell receptor molecules in regulating NK cell function in anti-tumor immune response.

Objective: To investigate the correlation between early-stage blood pressure indexes and prognosis in sepsis patients., Methods: A retrospective cohort study was conducted on the medical records of patients diagnosed with sepsis from 2001 to 2012 in the Medical Information Mart for Intensive Care-III (MIMIC-III) database. Patients were divided into survival group and death group according to the 28-day prognosis. General data of patients and heart rate (HR) and blood pressure at admission to ICU and within 24 hours after admission were collected. The blood pressure indexes including the maximum, median and mean value of systolic index, diastolic index and mean arterial pressure (MAP) index were calculated. The data were randomly divided into training set and validation set (4 : 1). Univariate Logistic regression analysis was used to screen covariates, and multivariate Logistic stepwise regression models were further developed. Model 1 (including HR, blood pressure, and blood pressure index related variables with P < 0.1 and other variables with P < 0.05) and Model 2 (including HR, blood pressure, and blood pressure index related variables with P < 0.1) were developed respectively. The receiver operator characteristic curve (ROC curve), precision recall curve (PRC) and decision curve analysis (DCA) curve were used to evaluate the quality of the two models, and the influencing factors of the prognosis of sepsis patients were analyzed. Finally, nomogram model was developed according to the better model and effectiveness of it was evaluated., Results: A total of 11 559 sepsis patients were included in the study, with 10 012 patients in the survival group and 1 547 patients in the death group. There were significant differences in age, survival time, Elixhauser comorbidity score and other 46 variables between the two groups (all P < 0.05). Thirty-seven variables were preliminarily screened by univariate Logistic regression analysis. After multivariate Logistic stepwise regression model screening, among the indicators related to HR, blood pressure and blood pressure index, the HR at admission to ICU [odds ratio (OR) = 0.992, 95% confidence interval (95%CI) was 0.988-0.997] and the maximum HR (OR = 1.006, 95%CI was 1.001-1.011), maximum MAP index (OR = 1.620, 95%CI was 1.244-2.126), mean diastolic index (OR = 0.283, 95%CI was 0.091-0.856), median systolic index (OR = 2.149, 95%CI was 0.805-4.461), median diastolic index (OR = 3.986, 95%CI was 1.376-11.758) were selected (all P < 0.1). There were 14 other variables with P < 0.05, including age, Elixhauser comorbidity score, continuous renal replacement therapy (CRRT), use of ventilator, sedation and analgesia, norepinephrine, norepinephrine, highest serum creatinine (SCr), maximum blood urea nitrogen (BUN), highest prothrombin time (PT), highest activated partial thromboplastin time (APTT), lowest platelet count (PLT), highest white blood cell count (WBC), minimum hemoglobin (Hb). The ROC curve showed that the area under the curve (AUC) of Model 1 and Model 2 were 0.769 and 0.637, respectively, indicating that model 1 had higher prediction accuracy. The PRC curve showed that the AUC of Model 1 and Model 2 were 0.381 and 0.240, respectively, indicating that Model 1 had a better effect. The DCA curve showed that when the threshold was 0-0.8 (the probability of death was 0-80%), the net benefit rate of Model 1 was higher than that of Model 2. The calibration curve showed that the prediction effect of the nomogram model developed according to Model 1 was in good agreement with the actual outcome. The Bootstrap verification results showed that the nomogram model was consistent with the above results and had good prediction effects., Conclusions: The nomogram model constructed has good prediction effects on the 28-day prognosis in sepsis patients, and the blood pressure indexes are important predictors in the model.

Objective: To explore the effects of high-flux hemodialysis (HFHD) on fibroblast growth factor 23 (FGF-23) and micro-inflammatory state in end-stage renal diseases (ESRD) patients to understand the advantages of HFHD in reducing complications in ESRD patients., Methods: A total of 60 subjects sheduled for hemodialysis at our hospital in 2012 were randomly divided into two groups of 3-month HFHD and 3-month low-flux hemodialysis (LFHD) (n = 30 each). The levels of serum factors, such as FGF-23, were observed before and after 3-month hemodialysis to evaluate the hemodialysis sufficiency of two groups and analyze the effects of FGF-23 related factors as well as different kinds of hemodialysis on microinflammatory state, biochemical indices and dialysis sufficiency., Results: Before hemodialysis, no intergroup statistical difference (P > 0. 05) existed in age, gender, basic disease, nutrition and levels of hemoglobin (Hb), albumin (ALB), estimated glomerular filtration rate (eGFR), Ca2+,P3- parathyroid hormone (PTIH) and FGF-23 before treatment. After 3-month hemodialysis in two groups, there were a negative correlation between FGF-23, Ca2 + or 1, 25-(OH)2VitD3, a positive correlation between FGF-23 and ALB, P3-, PTH, C-reactive protein (CHRP) or interleukin-6 (IL-6l) and a negative correlation between FGF 23 and HFHD group (P <0. 05) and no significant correlation between FGF-23 and Hb or KT/V (P < 0. 05). Variance analyses were conducted for each factor before and after hemodialysis, indicating that Hb, ALB and Ca2+ significantly increased in both groups after 3-month hemodialysis (P <0. 05) and 1, 25-(OH)2VitD3 significantly elevated in HFHD group (P < 0. 05) but not in LFHD (> 0. 05 . Serum phosphate significantly decreased after 3-month hemodialysis in both groups (P <0. 05) and CHIP, IL-6l, PTH and FGF-23 significantly decreased in HFHD group (P <0. 05), but not in LFHD group (P >0. 05). The levels of P3-, CRP, IL-6, PTH and FGF-23 after 3-month hemodialysis were significantly lower in HFHD group than those in LFHD group (P <0. 05) while the levels of Hb and 1, 25-(OH)2VitD3 after 3-month hemodialysis were significantly elevated in HFHD group compared with those in LFHD group (P < 0. 05). And no significant inter-group difference existed in the levels of Ca2 ALB and KT/V., Cconclusions: Compared with LFHD, HFHD is superior in treating anemia and improving nutrition. And HFHD can better decrease FGF-23, correct calcium and phosphorous metabolic disorder and improve micro-inflammatory state.

Objective: To investigate the variation of Th17 cell frequency and IL-17 level in rats infected with Helicobacter pylori (Hp)., Methods: A total of 30 rats were used to be infected with Hp by intragastric administration of bacterial suspension. Every 10 rats were sacrificed after 3, 6 and 9 weeks, respectively. The gastric tissues of rats were pathologically examined by HE staining. The level of IL-17 in the gastric tissues of rats was detected by ELISA. The flow cytometry was performed to determine Th17 cell frequency and reverse transcription PCR was to detect the level of IL-17 mRNA in single-cell suspensions of rat spleen., Results: Hp infection induced the obvious pathological changes in the rat gastric mucosa. The level of IL-17 in the gastric tissues increased with the prolonging of the Hp infection. Both Th17 cell frequency and IL-17 mRNA level in rat spleen cells infected with Hp at 3, 6 and 9 weeks were significantly higher than those in control rats, and they were significantly different when compared among different time points., Conclusion: Hp infection could induce the damage of rat gastric mucosa and increase IL-17 level in the stomach. Furthermore, Hp infection could up-regulate the Th17 cell frequency and IL-17 mRNA level in rat spleen cells.

There are plenty of materials recorded in the medical case records of the South Ridge. Through these records, it is possible to understand the patients' idea of their confidence toward the doctors, changing of invited doctors, pharmacological views, religious behaviors for inviting doctors and giving prognosis, payment to the doctors and their activities of public benefits. All these can offer help to the overall understanding of therapeutic history.

Objective: To raise the awareness of adenosquamous carcinoma of pancreas and discuss the treatment of it., Methods: Clinical data of 80 cases of pancreas adenosquamous carcinoma patients in the Department of Pancreas Surgery of Changhai Hospital of Second Military Medical University from December 2003 to October 2011 were analyzed. The diagnose and treatment methods were discussed. There were 61 male cases and 19 female cases who aged from 28 to 81 years, with an average age of 60 years. The primary symptoms included 46 cases (57.5%) of abdominal malaise, 6 cases (7.5%) of low back pain, 4 cases (5.0%) of abdominal swelling pain with low back pain, 15 cases (18.8%) of abdominal swelling pain with jaundice, 5 cases (6.3%) of painless jaundice, 3 cases (3.8%) of significantly decreased body-weight and 1 case (1.3%) of no symptom. All the patients had been identified as pancreas tumor suffers by ultrasound, enhanced CT scan or MRI. Totally there were 43 cases of head/unciform process tumors, 15 cases of pancreas body tumors and 22 pancreas tail cases.Health situation of all cases were follow-up observed in the outpatient department or telephoned every 3 months till 24 months after the surgery., Results: Among the 80 patients, 19 patients underwent pancreaticoduodenectomy (PD) , 19 patients received pylorus-preserving PD, with 4 cases of palliative resection and 1 case of total pancreatectomy. The volume of bleeding during the surgery varied from 50 to 3 500 ml with a blood transfusion volume varied from 0 to 4 000 ml. Consumed time for PD procedures was 90 to 260 min with 60 to 150 min for body and (or) tail resection with or without lienectomy. The mean diameter of tumor was (4.9 ± 2.2) cm. Pathological tests showed 35 cases of positive lymph nodes, adjacent organ invasion happened in 35 patients, however, nerve invasion were found in 68 cases.Eighteen cases occurred postoperative complications, including bleeding, pancreatic fistula, gastric emptying, incision fat liquefaction and infection, pleural effusion, ascites and nervous diarrhea. There were only 48 effective follow-up patients, with a loss ratio of follow-up by 40.0%, reasons for the loss includes change of contact information, refuse or unable to provide useful information by the relatives of the patients.Sixteen patients received chemotherapy, and 8 patients received radiotherapy after operation. All patients were dead in the effective follow-ups. The postoperative median survival time was 6 months (0.1 to 23.0 months)., Conclusions: Adenosquamous carcinoma of pancreas is a rare kind of malignant tumor, nerve invasion can be found in almost all the cases. Patients with adenosquamous carcinoma of pancreas have an unfavorable prognosis. The principle treatments are surgery, radiotherapy and chemotherapy.

Objective: To investigate the effect of the iron chelator deferoxamine (DFA) in suppressing microglia activation and protecting against secondary neural injury in a rat model of intracerebral hemorrhage (ICH)., Methods: SD rats were randomly divided into sham-operated group, ICH group and DFA treatment group. ICH model was established by infusion of type IV collagenase into the right basal ganglia, and starting from 1 h after the operation, the rats received intraperitoneal DFA injections every 12 h for 7 days. The iron content in the perihematoma brain tissue was determined at different time points after DFA administration, and OX42 immunohistochemistry was used to observe the changes in the microglia. The contents of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the brain tissue were detected by ELISA. The neural death and neurological deficiency were measured using Nissl staining and neurological scores, respectively., Results: The iron content in the brain tissues around the hematoma was significantly increased 3 days after ICH and maintained a high level till 28 days, accompanied by a marked increase of microglial cells as compared to the sham-operated group. DFA injection caused significantly decreased iron content in the brain tissue, reduced number of microglial cells, and lowered levels of IL-1β and TNF-α. Neuronal loss around the hematoma was obviously reversed after DFA injections, which resulted in improved neurological deficiency., Conclusion: DFA can suppress microglia activation by removing iron overload from the perihematoma brain tissue, thus reducing secondary neuronal death and neurological deficiency in rats with ICH.

We have established a human umbilical vein endothelial cell (HUVEC) line monoclonal cells with the stable expression of human tissue-type plasminogen activator (t-PA) gene to provide a basis for further study on the vascular tissue engineering. Recombinant plasmid pcDNA3. 1-Myc-His B (-)/t-PA was constructed by insertion of t-PAcDNA originated from PBS/t-PA into eukaryotic expression vector pcDNA3. 1-Myc-His B(-) and transfected into hUVEC line cells mediated by lipofectamine. The positive clones were obtained by the screen of G418. The transcription and expression of t-PA gene were investigated by RT-PCR and Western blotting respectively. The t-PA activity was measured by chromogenic substrate assay. The positive clone cells which transcripted the mRNA of t-PA gene was obtained by RT-PCR. Immunoreactive human t-PA of the medium was significantly increased in the group of transfected gene when compared with that in the controlled and transfected plasmid without t-PA gene group. The biological activity of the protein of the t-PA in the media was increased significantly in the positive clone cells with t-PA gene transfected. The HUVEC line monoclonal cells with the stable expression of t-PA gene was established successfully.