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Endoscopic submucosal dissection (ESD) is an effective treatment for colorectal tumors. However, lesions that cannot be lifted after submucosal injection are not indication for ESD. This is because the procedure is difficult, and the lesions are often considered as tumor invasion or submucosal fibrosis. The aims of this study are to evaluate the efficacy and safety of ESD for non-lifting lesions and to analyze the causes of non-lifting phenomenon.This retrospective study included 29 patients with non-lifting colon lesions resected by ESD from February 2018 to September 2021. Cases were observed for demographics, endoscopic findings, treatment outcomes, adverse events and endoscopic follow-up. We studied the pathological features of lesions to explore the reasons for non-lifting.Among 29 cases of non-lifting lesions, 20 lesions (69.0%) were 30 mm in diameter or larger. Most of lesions (96.6%) were non-lifting in center, and only one lesions (3.4%) had non-lifting of one side. The en bloc and curative resection rates of ESD were 100 and 86.2%, respectively. There was one (3.4%) delayed bleeding, no perforations and other complications. No tumor recurrence occurred during the follow-up period. For pathological features, 16 (55.2%) non-lifting lesions had submucosal fibrosis and only 4 cases (13.8%) had deep submucosal invasion. There were 9 cases (31.0%) of non-lifting lesions due to musculo-fibrous of muscularis propria anomaly (MMPA).MMPA is another reason for non-lifting signs besides invasive carcinomas and submucosal fibrosis. ESD should be considered in patients with large non-lifting adenoma instead of surgery.

Recent studies have emphasized the emerging importance of long noncoding RNAs (lncRNAs) in colorectal cancer (CRC). However, the functions and regulatory mechanisms of numerous lncRNAs in CRC have not been fully elucidated.To explore the functional role and underlying molecular mechanisms of lncRNA TNFRSF10A-AS1 in CRC.TNFRSF10A-AS1 expression was measured by quantitative real-time polymerase chain reaction in CRC, and the relationship between TNFRSF10A-AS1 levels and the clinicopathological features of CRC patients was analyzed. The effect of TNFRSF10A-AS1 expression on CRC proliferation and metastasis was examinedTNFRSF10A-AS1 was expressed at a high level in CRC and the upregulation of TNFRSF10A-AS1 was associated with advanced T grade and tumor size in CRC patients. A functional investigation revealed that TNFRSF10A-AS1 enhanced the proliferation, migration ability and invasion ability of colon cancer cellsTNFRSF10A-AS1 exerts a tumor-promoting function through the miR-3121-3p/HuR axis in CRC, indicating that it may be a novel target for CRC therapy.

Background Exosomes as the main therapeutic vectors of mesenchymal stem cells (MSC) for inflammatory bowel disease (IBD) treatment and its mechanism remain unexplored. Tumor necrosis factor-α stimulated gene 6 (TSG-6) is a glycoprotein secreted by MSC with the capacities of tissue repair and immune regulation. This study aimed to explore whether TSG-6 is a potential molecular target of exosomes derived from MSCs (MSCs-Exo) exerting its therapeutic effect against colon inflammation and repairing mucosal tissue. Methods Two separate dextran sulfate sodium (DSS) and 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced IBD mouse models were intraperitoneally administered MSCs-Exo extracted from human umbilical cord MSC (hUC-MSC) culture supernatant. Effects of MSCs-Exo on intestinal inflammation, colon barrier function, and proportion of T cells were investigated. We explored the effects of MSCs-Exo on the intestinal barrier and immune response with TSG-6 knockdown. Moreover, recombinant human TSG-6 (rhTSG-6) was administered exogenously and colon inflammation severity in mice was evaluated. Results Intraperitoneal injection of MSCs-Exo significantly ameliorated IBD symptoms and reduced mortality rate. The protective effect of MSCs-Exo on intestinal barrier was demonstrated evidenced by the loss of goblet cells and intestinal mucosa permeability, thereby improving the destruction of tight junctions (TJ) structures and microvilli, as well as increasing the expression of TJ proteins. Microarray analysis revealed that MSCs-Exo administration downregulated the level of pro-inflammatory cytokines and upregulated the anti-inflammatory cytokine in colon tissue. MSCs-Exo also modulated the response of Th2 and Th17 cells in the mesenteric lymph nodes (MLN). Reversely, knockdown of TSG-6 abrogated the therapeutic effect of MSCs-Exo on mucosal barrier maintenance and immune regulation, whereas rhTSG-6 administration showed similar efficacy to that of MSCs-Exo. Conclusions Our findings suggested that MSCs-Exo protected against IBD through restoring mucosal barrier repair and intestinal immune homeostasis via TSG-6 in mice.

A reasonable boarding model can effectively improve the boarding efficiency. Therefore, developing boarding models/strategies to improve the boarding efficiency has been an interesting topic in the air transportation. In this paper, we incorporate the group behavior and the quantity of luggage into the boarding process, and then develop an extended boarding model to investigate the effects of the two factors on the delay time and boarding time. The numerical results show that the quantity of luggage may make each passenger’s boarding behavior more complex, while the group behavior can shorten some passengers’ delay time and the total boarding time. The results can help administrators organize the boarding process and enhance the boarding efficiency.

The rapid increase of civil aviation has posed a great challenge to air traffic (especially aircraft boarding). In this study, we propose a new aircraft boarding model to explore the impacts of group behavior on each passenger's motion, seat conflict, check-in time, time of handling luggage as well as boarding time during the boarding process. The numerical results show that the group behavior has some positive impacts on the boarding efficiency, and that the impacts become more prominent with an increasing number of groups. Hence, the group behavior should be encouraged to enhance the efficiency during the boarding process.

Background Inflammatory bowel diseases (IBD) is a chronic intestinal disease characterized by persistent intestinal inflammation and mucosal damage. Mesenchymal stem cells (MSCs) transplantation is a promising therapy in IBD and other autoimmune diseases. Recent studies indicated that exosomes are the main therapeutic vectors of MSCs in treatment of IBD, but the therapeutic mechanism of exosomes derived from MSCs (MSCs-EXO) remains to be explored. The aims of our research is to explore whether MSCs-EXO have a protective effect on the intestinal barrier. Methods The serum-free cell culture supernatant of Human umbilical cord MSCs (hUC-MSCs) cultured for 48 hours was collected to extract exosomes. Two separate mouse models of IBD induced by dextran sulfate sodium (DSS) and 2,4,6-trinitrobenzenesulfonic acid (TNBS) were administered MSCs-EXO intraperitoneally. The effects of MSCs-EXO on intestinal inflammation, colon barrier function and proportion of T cells were investigated. Results Intraperitoneal injection of MSCs-EXO significantly ameliorated colitis, especially reduced disease activity index and mortality, and inhibited inflammatory cells infiltration. The protective effect of MSCs-EXO on intestinal barrier was demonstrated by reducing the loss of goblet cells and the intestinal mucosa permeability, improving the destruction of tight junctions (TJs) structures and microvilli, and increasing the expression of TJs proteins ZO-1, Claudin-1, and Occludin. MSCs-EXO administration downregulated the level of proinflammatory cytokines, including CXCL14, IL-1β, IL-11, and IL-12 and upregulated the anti-inflammatory cytokine IL-4 and TGF-β in colon tissue. MSCs-EXO also modulated the response of Th2 cells and Th17 cells in mesenteric lymph nodes (MLN). Conclusion Our findings suggested that MSCs-EXO promoted mucosal barrier repair and maintained intestinal immune homeostasis in murine colitis model.

The paper studied the effect on the performance of organic polymer solar cells at the active layer based on P3HT/PCBM from the addition of a solid derivative of nitrobenzene, 1-Bromo-4-Nitrobenzene, carried out experiment on 1-Bromo-4-Nitrobenzene doped with different doses in P3HT/PCBM active layer, and comparatively analyzed the performance parameters, absorption intensity, external quantum efficiency, fluorescence intensity, morphology characterization, and transient absorption of devices under different doses. Results showed that the organic polymer solar cells reached the maximum energy conversion efficiency, the energy conversion efficiency was improved from 2.2% to 3.4%, with an increase of 54 %, when the additive volume of 1-Bromo-4-Nitrobenzene was 25wt%. Addition of 1-Bromo-4-Nitrobenzene helped to improve the photoelectric conversion efficiency of organic polymer solar cells.

The reasonable boarding strategy can enhance the efficiency, so how to enhance the boarding efficiency has been a hot topic in the air transportation. In this paper, we incorporate the luggage quantity and the passenger’s group behavior into the boarding model, and develop an extended strategy to explore each passenger’s boarding behavior and the influences of the proposed strategy on the boarding efficiency. The numerical results indicate that the proposed strategy can relieve the congestions at the wicket and in the cabin, eliminate the seat conflicts, and reduce the time of handling luggage and the boarding time. This shows that the proposed strategy can enhance the boarding efficiency. The results can help administrators organize the boarding pattern to enhance the efficiency.

In order to ensure the linear array CCD normally and stably working in the spectral measurement, the data acquisition and storage circuit is presented. On the basis of analyzing the ILX511 driving timing, the circuit of data acquisition, processing, and storage based on CCD was designed. The CPLD was used to establish the correct sequence for the CCD clock pulse, AD converter clock, and FIFO writing signal, so the data acquisition, converter, and storage synchronously are achieved. The experiments show that the designed circuit is feasible.

The linear array CCD spectral acquisition system for a Photoelectric Direct Reading Spectrometer is presented. The spectral acquisition circuit, data processing and shortage circuit are designed. Taking microcontroller MSP430 as a control chip, Using PWM signals generated by MSP430 timer, the correct timing of CCD clock pulse, ADC clock and FIFO write enable signal was established. The experiment shows that the synchronization of spectral acquisition, data conversion and shortage was achieved, and the spectral acquisition system is feasible and reliability.

The J-V curve measurment and AFM technology were applied to study the relationship between P3HT:PCBM heterojunction film solar cell devices photovoltics parameter and blend solution concentration and annealed time of this device. The Voc, Jsc, FF and PCE of device were obtained from the device prepared by three blend solution concentration respectively. Data show that with increasing solution concentration PCE of solar cell device do not always improve and it achieves maximum when concentration is 20 mg/mL. Result indicates that only when solar cell device has active layer with proper thickness its performance will achieve the best effect. Additionally, photovoltaic parameters from four sample prepared by different annealed time were obtained also. Results indicate that the device with proper annealed time of 20 min at 130°C can achieve the best effect.

In order to improve laser-induced breakdown spectroscopy for low-level elements testing capability, the enhancement effects of KCl additive on the emission spectra of soil samples were studied. The laser spectrum analytical system is composed of a high-energy neodymium glass laser ablating samples, a multifunctional and automatic scanning spectrometer, and a CCD data acquisition system recording plasma spectra. The electron temperature and electron density of plasmas were calculated by measuring spectral line intensity and stark broadening respectively. The experimental results showed that with the increase in the KCl additive, the spectral intensity, signal-to-background ratio, the electron temperature and the electron density all went up firstly and then down. When 15% KCl was added, the radiation intensity of plasma reached the maximum value, the spectral lines intensity of element Mn, Fe, and Ti increased by 2.23, 1.13 and 2.04 than that without additive respectively, the spectral signal-to-background ratio increased by 1.33, 0.89 and 0.94 times respectively; while the electron temperature and electron density of plasmas were heightened by 14% and 38% respectively.

In order to improve the radiation characteristic of laser-induced plasma, with the national standard soil taken as the target sample, a laser spectrum analytical system which composed of a high-energy neodymium glass laser, a multifunctional and compact integrated spectrometer, and a CCD detector was used to detect the influence of the NaCl sample additive on the laser plasma radiation intensity. The electron temperature and the electron density of the plasmas were also calculated from the lines intensity and stark broadening of emission spectral line respectively. The experimental results indicated that with the increase in the NaCl additive, the spectral intensity, signal-to-background ratio, the electron temperature, and the electron density all went up firstly and then down. When 15% NaCl was added, the radiation intensity of the plasma reached the maximum value, the spectral lines intensity of element Mn, K, Fe, and Ti increased by 39.2%, 42.5%, 53.9% and 33.8% compared to that without additive respectively, the spectral signal-to-background ratio increased by 64.4%, 84.39, 44.55% and 58.2% respectively, while the electron temperature and the electron density of the plasmas were heightened by 0.17 times and 0.36 times respectively.

The devices with phosphorescent material tris(2-phenylpyridine)iridium [Ir(ppy)3] and fluorescent material 5,6,11, 12-tetraphenylnaphthacene [Rubrene] as dopants in two kinds of host were constructed in the present study. Respectively, the two kinds of host are polyvinylcarbazole [PVK] and 4,4'-N,N-dicarbazole-biphenyl [CBP]. We studied the properties of energy transfer between host materials and dopants. Firstly, the absorption and photoluminescence spectra of PVK, CBP, Ir(ppy)3 and Rubrene were measured. The spectral overlap between the photoluminescence of PVK and the absorption spectrum of Ir(ppy)3 is larger than that of Rubrene. The result of the spectral overlap for CBP is the same as PVK. It was shown that the energy transfer from the two host materials to Ir(ppy)3 is stronger than that to Rubrene. In addition, the energy transfer from Ir(ppy)3 to Rubrene is possible according to their absorption and photoluminescence spectra. We compared the electroluminescence properties of different devices. In devicel of ITO/PVK : Rubrene : Ir(ppy)3 (100 : 5 : x)/BCP(10 nm)/Alq3 (20 nm)/Al and device 2 ITO/CBP : Rubrene : Ir(ppy)3 (100 : 5 : x)/BCP(10 nm)/Alq3 (20 nm)/Al(x = 0, 3), under the same DC bias, the electroluminescence results show that energy transfer from host to Rubrene through Ir(ppy)3 is the main mechanism. And energy transfer is much more efficient in CBP as host than in PVK. In addition, at the same voltage, the light power of the device doped with Ir(ppy)3 and Rubrene is obviously stronger than that of the device doped with Rubrene only. When the concentration of Ir(ppy)3 increases, the light power decreases at the same voltage, and the effect of concentration quenching is enhanced.

With the increasing development of organic light emitting devices (OLED), interest in the mechanisms of charge carrier photogeneration, separation, transport and recombination continues to grow. Electromodulation of photoluminescence has been used as an efficient probe to investigate the evolution of primary excitation in all electric field. This method can provide useful information on carrier photogeneration, the formation and dissociation of excitons, energy transfer, and exciton recombination in the presence of electric field. The operation of OLED brings electrons and holes from opposite electrodes and generates singlet and triplet excitons. However, triplet excitons are wasted because a radiative transition from triplets is spin-forbidden. Spin statistics predicts that singlet-to-triplet ratio is 1 : 3 in organic semiconductors. One way to harvest light from triplet excitons is to use phosphorescent materials. These materials incorporate a heavy metal atom to mix singlet and triplet states by the strong spin-orbit coupling. As a result, a spin forbidden transition may occur allowing an enhanced triplet emission. Among phosphorescent materials, Ir(ppy)3 has attracted much attention because of its short triplet lifetime to minimize the triplet-triplet annihilation. High quantum efficiencies have been obtained by doping organic molecules and in polymers with Ir(ppy)3. In the present paper, the photoluminescence and electroluminescence spectra of Ir(ppy)3 doped PVK film are measured at room temperature. The device structure is ITO/PEDOT : PSS/PVK Ir(ppy)3/BCP/Alq3/Al. The results show that the luminescence capabilities of devices are different when the concentration of Ir(ppy)3 is different. When the concentration of Ir(ppy)3 is suitable, the luminescence of PVK is lower but that of Ir(ppy)3 is stronger relatively, indicating that the energy transfer from the host materials to the guest materials is sufficient. It is concluded that the device with 5% of Ir(ppy)3 has the best luminescence properties according to its light power-current-voltage curve, meaning that the best concentration of Ir(ppy)3 in such kind of device is 5%.

The effects of PBD on the luminescence properties of PVK : Ir(ppy)3 codoped with PBD with lower concentration were investigated. Two kinds of devices with the structures of ITO/PVK : Ir(ppy)3/PBD/Al and ITO/PVK : Ir(ppy)3 : PBD/ Al were fabricated. PVK emission appears in the electroluminescence (EL) spectra of ITO/PVK : Ir(ppy)3/PBD/Al. The reason is that the Forster energy transfer is not efficient enough in the emission layer, and then the emission layer was doped with PBD. A set of devices were fabricated with the configuration of ITO/PVK : Ir(ppy)3 : PBD/BCP/Al. The doping weight ratio of PVK : Ir(ppy)3 was fixed as 100 : 1, and the weight ratio of PBD changed from 100 : 0 (PVK : PBD) to 100 : 20. The photoluminescence (PL) spectra and electroluminescence (EL) spectra of these devices were measured. Through the analysis of their luminescence, it was found that the brightness of these devices codoped with PBD is improved. The brightness of these devices increases with increasing PBD doping ratio as the ratio does not exceed 100:10 (PVK : PBD). The PBD codoping enhances the injection and transportation of electron, resulting in the enhanced carrier recombination probability. If the doping ratio of PBD exceeds 100 : 10 (PVK : PBD), the brightness of the device decreases. There are two reasons. One is that the superfluous PBD causes the carriers to be imbalanced and induces a larger leakage current. The other is that the superfluous PBD may block the hoping of holes or electrons between the PVK chains. The brightness is the strongest when the weight ratio of PVK to PBD is 100 : 10.

The time-resolved spectra of free photoelectrons and shallow-trapped electrons in the T-grains AgBrI emulsion were simultaneously detected with microwave absorption and dielectric spectrum detection technique. The results indicate that the electron trap effects of sulfur sensitization centers and sulfur-plus-gold sensitization centers are different with equal quantities of Na2S2O3 added. The sulfur sensitization centers acted as a deep electron trap to pick up the electronic decay because of increasing the number of deep trapped electrons, while the sulfur-plus-gold sensitization centers as a shallow electron trap decrease the electronic decay through effectively controlling the recombination between the electrons and the holes. The depth of sulfur-plus-gold sensitization center is shallower than that of sulfur sensitization center after the KAuCl4 is added. The effects of sulfur sensitization center and sulfur-plus-gold sensitization center on the photoelectron decay are different in different sections of decay curves through the change in electron time-resolved spectra.

Microwave absorption and film dielectric spectrum detection technology was used to study the influence of complex K4Ru (CN)6 on the photoelectron decay time-resolved spectrum of cubic AgCl crystals illuminated in this paper. The results indicate that the influence of the doping content and doping position of the complex K4Ru(CN)6 on the photoelectron decay time-resolved spectrum is evident. The photoelectron decay process of this emulsion is slowest, and the photoelectron lifetime is longest when doped with K4Ru (CN)6 of 2.45 x 10(-5) mol x (mol Ag)(-1) at doping positions of 75% Ag.

Photoelectrons plays an important role in the latent image formation process of silver halide materials, and the decay characteristic of photoelectrons are dependent on the structure of silver halide microcrystals to a great extent. In this paper, the decay spectra of free photoelectrons and shallow-trapped electrons were obtained by optics and microwave double resonance technology. The depth and density of electron traps in silver halide microcrystals were discussed. Moreover, using the lifetime of free photoelectrons, the optimal doping amount of shallow electron trap dopants was found by analyzing the distribution condition of electron traps in silver halide.

Efficient free‐running lasing on the XeF(C‐A) electronic transition has been demonstrated in an unmodified commercial discharge excited excimer laser at a reduced buffer gas pressure of 2.2 atm and a moderate low pump rate of 2.76 MW/cm3, using a four‐component gas mixture of Xe, NF3, Kr, and He with a net peak gain of 1.24%/cm. The laser spectrum showed a peak wavelength at 477 nm and a bandwidth of 32 nm (FWHM). The laser output energy was 1.17 mJ, representing peak power, energy density, and intrinsic efficiency values of 0.062 MW, 9 mJ/l, and 0.016%, respectively.