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We report an efficient alkyl transfer strategy for the direct β-alkylation of chalcones using commercially available alkyl bromides as alkyl reagents. In this transformation, the

Since FRB 200428 has been found to be associated with an X-ray burst from the Galactic magnetar SGR J1935+2154, it is interesting to explore whether the magnetar bursts also follow the similar active periodic behaviour as some repeating FRBs. Previous studies show that there is possible period of about 230 days in SGR J1935+2154 bursts. Here, we collected an updated burst sample from SGR J1935+2154, including all bursts reported by Fermi/GBM and GECAM till 2022 January. We also developed a targeted search pipeline to reveal more bursts from SGR J1935+2154 in the Fermi/GBM data from 2008 August to 2014 December (i.e. before the first burst detected by Swift/BAT). With this burst sample, we re-analysed the possible periodicity of SGR J1935+2154 bursts using the Period Folding and Lomb–Scargle Periodogram methods. Our results show that the periodicity ∼238 days reported in literature is probably fake and the observation effects may introduce false periods (i.e. 55 days) according to simulation tests. We find that, for the current burst sample, the most probable period is 126.88 ± 2.05 days, which could be interpreted as the precession of the magnetar. However, we note that the whole burst history is very complicated and difficult to be perfectly accommodated with any period reported thus far, therefore more monitoring observations of SGR J1935+2154 are required to test any periodicity hypothesis.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) is a dedicated mission, launched in December 2020, for gamma-ray transients, including gamma-ray bursts (GRBs) and soft gamma repeater (SGR) bursts in the multimessenger and multiwavelength astronomy era. Since GECAM consists of two independent spacecrafts (or say instruments), and the framework of data analysis for multiple spacecrafts is distinctive from that for only one spacecraft, which is the case for most GRB missions, we developed a dedicated pipeline called Energetic Transients Joint Analysis System for Multi-INstrument (ETJASMIN) for GECAM mission. This pipeline has been naturally extended to incorporate data from other gamma-ray instruments, including the operating missions, such as Insight-HXMT/HE, Fermi/GBM, Swift/BAT, INTEGRAL/SPI-ACS, Konus-Wind, and GRID, as well as the forthcoming missions, such as SVOM/GRM and HEBS. In this paper, we present this pipeline with a focus on the data analysis procedures, methodology, and results in terms of the localization, verification (classification), spectral, and temporal analyses of gamma-ray transients. We show that this pipeline could provide more accurate, reliable, and comprehensive results than that of individual spacecraft, which is beneficial for gamma-ray transients observation.

Quantum key distribution cannot satisfy some users without quantum capability, so semi-quantum key distribution emerges as the times required. Semi-quantum key distribution protocol is described as Alice has quantum ability to prepare and measure qubits with an arbitrary basis, while Bob only measures qubits with the computational basis or reflects qubits to Alice. However, most existing semi-quantum key distribution protocols have been performed with low eavesdropping detection probability. In this paper, we present an innovative semi-quantum key distribution protocol with high efficiency based on EPR and single-particle hybridization, in which the specific contents of {\scriptsize CTRL} or {\scriptsize SIFT} operations have been newly defined. Then, the security analysis indicates the proposed protocol is asymptotically secure with more high eavesdropping detection probability against individual eavesdropping attacks. Moreover, the efficiency analysis shows that the presented protocol is more efficient than similar literatures.

A Cd(ΙI)-based luminescent coordination polymer, namely [Cd(L)2(H2O)2]n (1), has been synthesized by 1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene ligand (HL) and structurally characterized. The selectiv...

Co(II) and Cu(II) complexes, [Co2(H2L)2(phen)2(H2O)4](H2O)2 (1) and [Cu2(L)0.5(phen)2Cl2]n (2) [H4L = 5,5'-(diazene-1,2-diyl)diisophthalic acid, phen = 1,10-phenanthroline], have been solvothermall...

In this work, Monte Carlo simulations are used to study the critical adsorption behaviors of flexible polymer chains under the action of an external driving force F parallel to an attractive flat surface. The critical adsorption temperature Tc decreases linearly with increasing F, indicating that the driving force suppresses the adsorption of polymer. The conformation of polymer is also affected by the driving force. However, the effect of F is dependent on the competition between the driving force and temperature. Under strong force or at low temperature, the polymer is stretched along the direction of the force, while under weak force or at high temperature, the polymer is not stretched. When the force is comparable to the temperature, the polymer may be stretched perpendicular to the driving force, and below Tc, we observe conformational transitions from parallel to perpendicular and again to parallel by decreasing the temperature. We found that the perpendicular stretched conformation leads the polymer chain to synchronously move along the direction of the driving force. Moreover, the conformational transitions are attributed to the competition and cooperation between the driving force and the temperature.

The g-C3N4/BiPO4 composites have been successfully synthesized via a one-pot hydrothermal process, which can be used to degrade the organic dyes (rhodamine B and methylene blue) under simulated sunlight irradiation. X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis diffuse reflectance spectra and Fourier transform infrared (FTIR) spectroscopy have been employed to characterize the samples. The g-C3N4/BiPO4 composites exhibited higher photocatalytic activity than pure BiPO4. And the optimum photocatalyst shows the outstanding photocatalytic activity, which exhibited 99.0% and 86.6% decolorization rate of RhB and MB, respectively.

Semi-quantum private comparison protocol permits two classical participants to compare the equality of their private information with the help of a semi-honest third party without disclosing privacy. An innovative semi-quantum private comparison protocol based on maximally entangled Greenberger–Horne–Zeilinger-type states has been discussed. The proposed protocol is efficient and without the pre-shared keys. Next, the security analysis guarantees the presented protocol is asymptotically secure against the outsider and the insider attacks. Moreover, the qubit efficiency of the presented protocol is 3.125%. The efficiency comparison shows that it improves the efficiency by 125% for the literature without pre-shared keys.

Two-stop-line signalized roundabouts (TSLSR) are widely utilized in China. To calculate the capacity and optimal cycle length accurately, a model considering internal space constraint of the roundabout is developed in this paper. Firstly, the operational principle of TSLSR is analyzed. TSLSR is modeled as being equivalent to a four-phase intersection with left-turn protection phases, and the left-turn lane is further simplified as the “short-lane model”. Secondly, based on the above analysis, the capacity of TSLSR is modeled and additionally, the accuracy and sensitivity of the model are also analyzed. Finally, the optimal cycle length of TSLSR which maximizes the capacity is put forward. Results show that the accuracy of the capacity model is low without considering the internal space constraint of the roundabout. However, the model developed in this paper is shown to improve the accuracy (about 20%) and control the relative error to be within 10%. The parameter sensitivity analysis demonstrates that the cycle length and radius of the central island have a significant influence on the capacity of the left-turn lane and results in an optimal value of signal cycle length maximizing the capacity.

It is of particular interest to investigate nuclear fusion reactions generated by high-intensity lasers in plasma environments that are similar to real astrophysical conditions. We have experimentally investigated $$^2 \hbox {H}({d},{p})^3 \hbox {H}$$, one of the most crucial reactions in big bang nucleosynthesis models, at the Shenguang-II laser facility. In this work, we present a new calibration of CR-39 solid-state track detectors, which are widely employed as the main diagnostics in this type of fusion reaction experiment. We measure the dependence of the track diameter on the proton energy. It is found that the track diameters of protons with different energies are likely to be identical. We propose that in this case, the energy of the reaction products can be obtained by considering both the diameters and gray levels of these tracks. The present results would be very helpful for analyzing the $$^2 \hbox {H}(d,p)^3 \hbox {H}$$ reaction products recorded with the same batch of CR-39 solid-state track detectors.

The g-C₃N₄/BiPO₄ composites have been successfully synthesized via a one-pot hydrothermal process, which can be used to degrade the organic dyes (rhodamine B and methylene blue) under simulated sunlight irradiation. X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis diffuse reflectance spectra and Fourier transform infrared (FTIR) spectroscopy have been employed to characterize the samples. The g-C₃N₄/BiPO₄ composites exhibited higher photocatalytic activity than pure BiPO4. And the optimum photocatalyst shows the outstanding photocatalytic activity, which exhibited 99.0% and 86.6% decolorization rate of RhB and MB, respectively.

Typical air pollution events involving ozone (O3) and PM2.5 occurred frequently in China, while the fine-scale pollution variation, especially at a neighborhood level (2 km*2 km), is complex and still not clear. To assess how urban form and meteorology influence neighborhood air pollution distribution, this study took the Minhang district in Shanghai, as experimental cases, and performed a neighborhood-scale investigation on O3 and PM2.5 by using mobile measurements. Both land-use regression model and decision tree model were used to examine the relationship between air pollutant concentration and influenced variables. As the decision tree model captured the linear and non-linear relationship between variables, it was demonstrated that explained more variations of O3 and PM2.5 concentrations than the LUR model. The results also showed that O3 concentrations were mainly affected by meteorological factors while PM2.5 concentrations were more heavily determined by background level and residential area. Both O3 and PM2.5 showed a significant correlation with air temperature, traffic volume, building height, and green space. Interestingly, green spaces were negatively correlated with the PM2.5 variations, which was almost the opposite to that of O3. With the superiority to the discrete observation, the decision tree model based concentration surfaces clearly revealed the heterogeneity of O3 and PM2.5 distributions. This study not only preliminarily identifies the impacts of land-use type and meteorological factors on the spatial patterns of O3 and PM2.5, but also provides a possible alternative method for assessing the neighborhood air pollution in the future.

The adsorption of a polymer chain on an attractive nano-sized spherical particle is studied by using Monte Carlo simulation. The polymer-particle interaction is treated as Lennard-Jones potential with strength e PP. The critical adsorption point e * PP is estimated from the largest fluctuation of the number of monomers contacted with particle. We find that e * PP is dependent on the comparison between particle size σ p and R G0, the mean radius of gyration of polymer in dilute solution. e * PP decreases with an increase in σ p at σ p

The conformational properties of a polymer chain adsorbed on an attractive spherical nanoparticle are studied by using Monte Carlo simulations. The adsorption degree of polymer is described by the number of adsorbed monomers n a and the length of adsorbed block l a . The configuration of the adsorbed polymer on a nanoparticle is described by trains, loops, and tails. We find three different structures for the adsorbed polymer: a structure with trains, loops, and tails at small polymer-nanoparticle interaction strength e pn , a structure with a train and a tail at large e pn , and a structure with trains and loops at large n a . In addition, we find that the mean number of adsorbed monomers is scaled with l a as ~ l a α at e pn ≥ 1, and the exponent α increases with e pn . Our results indicate that both the adsorption degree and the configuration of the adsorbed polymer are dependent on the polymer-nanoparticle interaction strength, the number of adsorbed monomers, and the length of adsorbed block.

Conformational properties of end-grafted flexible diblock copolymers were studied by using Monte Carlo simulation. The copolymers, XAnBn and XBnAn, are grafted with the end X to a flat surface which attracts monomers A but repulses monomers B. Results show that the blocks A in XAnBn and XBnAn are adsorbed upon the surface at low temperature, and the adsorption of blocks A takes place roughly at the same temperature. However, the conformational size and instantaneous shape of the blocks A and B in XAnBn and XBnAn are different. The possible reasons were discussed and they were interpreted by different properties and grafting locations of the two blocks.

The effect of nanosized fillers on the equilibrium and dynamic properties of a single polymer chain has been studied by using off-lattice Monte Carlo (MC) simulation. Fillers of identical size are arranged periodically in the system and the Lennard-Jones (LJ) interaction is considered between the polymer and fillers. Our results show that the statistical size and dynamic diffusion properties of the polymer are not only dependent on the size of the polymer relative to the size of fillers and the distance between fillers, but also dependent on the interaction between the polymer and filler. The statistical size of the polymer can increase or decrease. Normal diffusion is always observed for long polymers and small fillers, whereas a transition from a desorbed state to an adsorbed state is observed for short polymers and large fillers. Finally, the size and diffusion of the polymer on an infinitely large surface are studied for comparison.

The ground state structures of copper clusters with different sizes along with their aggregation have been systematic investigated using Amsterdam Density Functional (ADF) and Atomistix ToolKit (ATK) programs. On the basis of geometry optimization, some Cu clusters with more stable structures which were not reported previously have been revealed. In most cases, these Cu clusters prefer to adopt icosahedral structures which originate from the 13-atom icosahedron. It has also been demonstrated that the interaction between two Cu clusters is anisotropic, which is attributed to their charge distribution, especially the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of Cu clusters. Moreover, we have carried out the simulation of Cu clusters aggregation on the silicone oil substrate by means of Monte Carlo (MC) method, which shows good consistence with our previous experimental studies.

Unreasonable settings of bus stops widely exist in Chinas satellite cities, which restrict the traffic capacity and hold up the public traffic efficiency. This paper takes Yanjiao as an example to summarize the common problems existed in setting up bus stops and present improving proposals through the analysis of the current situation.

This paper proposes a new type of internal meshing cycloid rotor pump-Double enveloping cycloid pump. It is characterized by double contact lines between the inner and the outer rotor so that it has outstanding advantages, such as better sealing capacity, higher outlet pressure and volumetric efficiency etc. Based on the brief introduction of the equations of the inner and the outer rotors’ tooth profile, the composition and characteristics of the outer rotor’s tooth profile for the double enveloping cycloid pump are discussed in detail, the calculation method of the normal meshing clearance between the outer rotor and the modified inner rotor is introduced, and the calculation example is given. Result shows that the works in this paper will help to design the new type cycloid rotor pump with high performance.

It is well recognised that a significant amount of solid waste is produced from construction work. The increasing generation of construction waste such as used timber formwork, obsolete concrete and packaging, has caused significant pollution to the environment and risen public concern particularly in densely populated cities, such as Hong Kong. The minimization of construction waste has therefore become a pressing issue in pursuing the practice of sustainable construction. This paper shows the betterment of replacing in situ concreting with precast slabs for temporary works to improve sustainable construction performance. Construction waste from the obsolete concrete constitutes a large part of the construction solid waste in a typical building project. The reduction on the obsolescence by using precast slabs can significantly contribute to improving sustainable construction performance. This study identifies cost saving and the betterment of environmental performance by using precast concrete slabs over the in situ concreting. The data used for analysis in the paper were collected from statistics reports and a case study in Hong Kong construction practice. From the case study results, about 43.93%, 64.01% and 70.70% of the cost of using cast in situ concreting can be saved by reusing precast slabs once for temporary works, twice and three times respectively. The findings provide evidence for promoting the use of precast slabs for temporary works, and contribute to the improvement of sustainable construction performance.

As an important optical splitting element, grating is used in many different spectrometers and spectrographs. Spherical varied-line-spacing grating (SVLSG) is easily combined with array detectors to get a wide wavelength range of spectrums in one time, because it can focus the spectrums in approximately a plane. Therefore, it's widely used in many spectral instruments. We usually only know the central groove density of a commercial grating and its mounting parameters, while its line spacing parameters are unknown. Moreover, the mounting parameters are optimized within the whole using wavelength range of the grating. However, in most circumstances only part of the wavelength range is used. Therefore, the mounting parameters are not optimized for the needed wavelength range. Under this condition, in this article we developed a method based on the focusing theory of the flat-field grating and the mounting parameters the manufacture provided to deduce the line spacing parameters of the grating. With these parameters, we can optimize the detector position according to the wavelength range we need and ray tracing can be done to test the optical system. In this article we developed a high spectral resolution ultraviolet spectrograph, covering a wavelength range of 230-280 nm. The grating used in this spectrograph has a central groove density of 1 200 lines x mm(-1) and a designed wavelength range of 170-500 nm. We deduced the line spacing parameters of the grating and optimized the detector mounting parameters. Hollow cathode lamps of different elements were used to calibrate the spectrograph and test the spectral resolution of it. Wavelength calibration of the spectrograph has been done with the parameter fitting method, and the calibration accuracy is better than 0.01 nm. Results show the spectral resolution of the spectral graph is about 0.08 nm at 280.20 nm.

The effect of randomly distributed nano-sized fillers on the equilibrium and dynamical properties of linear polymers is studied by using off-lattice Monte Carlo simulation. Lennard-Jones interactions between polymers and fillers are considered. Results show that the statistical dimensions and dynamical diffusion of polymer are dependent on the polymer-filler interaction strength εpf. The mean square radius of gyration 〈RG(2)〉 shows a minimum at a critical polymer-filler interaction εpf*. The value of εpf* decreases with the increase in the polymer length or the concentration of fillers. The exponent ν in 〈RG(2)〉 ∼ N(2ν) is a typical value of self-avoiding walking chain at small εpf but it increases sharply to a bigger value at εpfεpf*. The mean square displacement decreases with the increase in εpf. Moreover, the normal diffusion of the polymer at weak interactions changes to subnormal diffusion at moderate and strong attractions. We find that polymers diffuse in dilute filler regions at weak attraction and diffuse in dense filler regions at strong attraction.

Disuse induces rapid and severe bone loss in larger mammals as a result of greatly elevated osteoclastic resorption. In this study, we tested whether risedronate (RIS), a potent inhibitor of osteoclastic activity, would effectively prevent cancellous bone loss in female beagles (5-7 years old, N = 28) subjected to single forelimb immobilization (IM) for 12 months. Age-matched, non-IM dogs served as controls (Con). Half the animals from each group received RIS 1 mg/kg p.o. daily (Con + RIS, IM + RIS). Remaining dogs received sterile water (Con, IM). Histomorphometry showed that IM caused a dramatic reduction in cancellous bone mass (-71%) of distal 2nd metacarpals, characterized by marked decreases in trabecular width (-51%) and number (-41%), and 4-fold increases in the indices of bone resorption (eroded surface, osteoclast number, and surface). Bone formation indices (calcein-labeled surface, osteoid surface, and bone formation rate) were also significantly higher in IM than in controls. Activation frequency in IM increased about 4-fold beyond control level. RIS treatment reduced, but did not abolish cancellous bone loss due to immobilization. IM animals treated with RIS lost nearly 50% of cancellous bone mass, while trabecular width and number were reduced by 31% and 25%, respectively. In both RIS-treated control and IM animals, overall bone formation parameters (mineralized bone surface fraction and bone formation rate) remained roughly at intact control levels; however, mineral apposition rate relative to intact control was reduced 40% in RIS-treated control and 86% in RIS-treated IM animals. These results indicate that high-dose RIS treatment might suppress osteoblastic function, especially under long-term disuse. Interestingly, bone resorption parameters in RIS-treated IM animals reached levels even higher than in vehicle-treated IM animals; values for eroded surface, osteoclast number, and surface were 84%, 53%, and 83% above vehicle-treated IM values, respectively. Our data indicate that risedronate treatment is partially effective in preventing cancellous bone loss during long-term disuse. Moreover, our results suggest that bisphosphonates can impair the ability of mature osteoclasts to resorb bone, but cannot overcome the strong stimulus for osteoclast recruitment caused by long-term disuse.

Laser-Induced Breakdown Spectroscopy (LIBS) is strongly time related. Time-resolved LIBS measurement is an important technique for the research on laser induced plasma evolution and self-absorption of the emission lines. Concerning the temporal characteristics of LIBS spectrum, a method is proposed in the present paper which can achieve micros-scale time-resolved LIBS measurement by using general ms-scale detector. By setting different integration delay time of the ms-scale spectrum detector, a series of spectrum are recorded. And the integration delay time interval should be longer than the worst temporal precision. After baseline correction and spectrum fitting, the intensity of the character line was obtained. Calculating this intensity with differential method at a certain time interval and then the difference value is the time-resolved line intensity. Setting the plasma duration time as X-axis and the time-resolved line intensity as Y-axis, the evolution curve of the character line intensity can be plotted. Character line with overlap-free and smooth background should be a priority to be chosen for analysis. Using spectrometer with ms-scale integration time and a control system with temporal accuracy is 0.021 micros, experiments carried out. The results validate that this method can be used to characterize the evolution of LIBS characteristic lines and can reduce the cost of the time-resolved LIBS measurement system. This method makes high time-resolved LIBS spectrum measurement possible with cheaper system.

We demonstrated an experiment of femtosecond-laser damage threshold on GaAs wafer, the damage threshold was measured from 50 to 400fs. The mechanism was discussed through injection power, pulse duration and ablation profile. The results showed that the damage threshold increased with the pulse duration, the relationship between diameter of ablation hole and laser power density was also analyzed. It was concluded that the main factor affecting the damage threshold was photon ionization and collision ionization.

A high-resolution extreme ultraviolet (EUV) spectrometer has been developed to diagnose the magnetically confined plasmas. A holographic spherical varied line spacing concave grating which provides a flat focal plane is used as the diffraction element working with the grazing incidence angle of 3 degrees. The nominal groove density is 1200 lines x mm(-1). A deeply cooled back-illuminated CCD camera is used as the spectra detector and a mechanical shutter is used to control the time of exposure. It covers the wavelength range of 5-50 nm with the CCD cameral moving along the spectra focal plane to cover different wavelength range interested. Spectrometer design is presented and it was tested by a Penning discharge light source. By the wavelength calibration, the actual parameters of the optical system were calculated and the wavelength accuracy is 0.003 nm. Results show that the spectral resolution is about 0.015 nm at 20 nm with the width of entrance slit opened at 30 microm, which agrees with the design goal.

In the present paper, the authors propose a method to measure the spatial and spectral distribution of hollow cathode lamp by imaging spectrometer. A push-broom convex grating imaging spectrometer based on Offner system is presented, with wavelength range 400-1 000 nm, field angle 22 degrees and spectral resolution 2-3 nm. The spatial distribution of Hg hollow cathode lamp was measured for the first time; this gives the spatial intensity distribution for different wavelengths and spectral distribution at different positions, with high spatial and spectral resolution. Also the hyperspectral data under different working current condition was obtained in order to analyze the differences of the distribution. It will be a powerful tool for the spatial and spectral properties measurement of hollow cathode lamps and other kinds of light sources.

To discuss the relationship between corneal lymphangiogenesis and inflammation index (IF) in alkali burned corneas.Experimental research. Rat corneal hemangiogenesis and lymphangiogenesis were examined by 5'-nase-alkaline phosphatase (5'-NA-ALP) double enzyme-histochemistry and whole mount immunofluorescence at 1 day, 3 days, and 1, 2, 3, 4, 5, 6, 7, 8 weeks after alkaline burns, and the blood vessel counting (BVC) and the lymphatic vessel counting (LVC) were recorded. The state of corneal inflammation was observed under the slit lamp and evaluated by inflammation index (IF) grading at the same time. Then, the association of LVC with IF was examined. In addition, eleven human alkali burned corneas were obtained from 11 patients undergoing corneal transplantation in Zhongshan Ophthalmic Center from January 2005 to June 2008. Corneal lymphangiogenesis was examined by lymphatic vessel endothelial receptor (LYVE-1) immunohistochemistry. The significance of the differences in IF, inflammatory cells counting, burn history, and age between two groups was analyzed by using paired student's t-test.New lymphatic vessels were present in rat alkali burned corneas. Corneal lymphangiogenesis developed 3 days after alkaline burns, reached the top 2 weeks after the injury, then decreased gradually, and disappeared at the end of the 5th week. Corneal lymphatics occurred behind corneal inflammation, but disappeared before corneal inflammation and hemangiogenesis. LVC was strongly and positively correlated with IF (r = 0.572, P0.01) after corneal alkaline burns. Among eleven human alkali burned corneas, corneal lymphatic vessels were present in 3 corneas. Compared with the other 8 cases without corneal lymphangiogenesis, the scores of IF was significantly higher (t = 3.28, P0.05), the inflammatory cells counting dramatically increased (t = 2.42, P0.05), but the age decreased significantly (t = 2.62, P0.05). However, the difference in burn history between two groups was not significant (t = 1.28, P0.05).Corneal lymphangiogenesis develops after alkaline-burns and correlates closely with inflammation index.

To investigate the effects of benzalkonium chloride (BAC), a preservative used in many ophthalmic topical solutions, on mucin1 (MUC1) in human conjunctival epithelial cells in vitro.Cultured epithelial cells obtained from human conjunctiva were exposed to medium containing BAC solutions at 0.0100%, 0.0050%, 0.0010%, 0.0005% and 0.0001% concentrations for a period of 15 min. Cells were examined after treatment and 6, 12, 24, 48 and 72 h later. The relative expression of the MUC1 mucin gene was determined by conventional reverse transcription-polymerase chain reaction (RT-PCR). Monoclonal antibody for MUC1 was used in Western blot analysis to detect MUC1.Cell exposure to 0.0100% and 0.0050% BAC decreased the expression of MUC1 at gene level between 12 and 72 h after treatment. Cells treated with 0.0010% and 0.0005% BAC decreased the expression of MUC1 between 24 and 48 h after treatment, recovered 72 h after treatment. At protein level, cells exposed to 0.0100% BAC decreased MUC1 between 24 and 72 h, 0.0050% BAC between 12 and 72 h, 0.0010% BAC 72 h later.These results suggest that BAC induces decreased expression of MUC1 at both gene and protein levels. The mode of BAC-induced decreased expression of MUC1 is dose-dependent.

BK virus (BKV) is a subtype of papovaviridae. The latent and asymptomatic infection of BKV is common among healthy people. The incidence of BKV re-activation in renal transplant recipients ranges 10%-68%. About 1%-7% of renal transplant recipients will suffer from BKV-associated nephropathy (BKVAN), and half of them will experience graft failure. This paper summarizes the re-activation mechanism of BKV as well as the risk factors, pathology, diagnosis, and treatment of BKVAN.

To investigate the preventative effect of mutant kringle 5 (mK5) eye drops on corneal allograft rejection.It was a experimental study. The outbred strain F344 and Lewis rats were used as donors and recipients respectively. Sixty Lewis rats were randomly divided into B, C, D and E Group; Group A, F344 rats autograft control; Group B, allograft control (the control groups were given normal sodium only); Group C and D, allograft groups, were treated with 5 mg/L and 10 mg/L mK5 eye drops respectively; Group E, allograft group, was treated with 0.1% dexamethasone eye drops. The eye drops were applied one drop four times per day for two weeks, the occurrence and development of corneal allograft rejection and corneal neovascularization (CNV) was observed every other day by slit-lamp microscope, the grafts were evaluated clinically by means of Holland's scoring system and the area of CNV was calculated. Nine rats per group were killed on the 14th day, and the corneas were taken for histopathological examinations. Analysis of variance was used to analyze the outcomes.The average graft survival time of Group B, C, D and E was (9.3 +/- 2.1), (21.1 +/- 7.3), (23.5 +/- 10.8) and (28.2 +/- 19.1) d respectively, Compared with Group B, Group C and D had a statistically significant prolongation of survival time (q = 10.24, 13.47; P0.05). Though treated with 0.1% dexamethasone eye drops (Group E) prolonged transplant survival time as compared with mK5 eye drops, but the difference was not statistically significant (q = 2.54, 1.49; P0.05). The occurrence of CNV in Group A was (3.1 +/- 0.8) d, Group B (2.6 +/- 0.5) d, Group C (6.4 +/- 0.5) d, Group D (7.8 +/- 0.7) d and Group E (5.3 +/- 1.0) d. Significant difference (q = 31.58, 51.21, 19.98; P0.05) was found between groups C, D, E and Group A. There were also significant difference between groups C, D, E and Group B (q = 43.87, 67.14, 24.53; P0.05). The CNV areas of Group C and Group D were also smaller than Group B (q = 30.76, 62.14; P0.05). The results was similar compared with Group E (q = 15.20, 25.64; P0.05). Fewer inflammatory cells and CNV were found in the cornea of the groups treated with mK5 eye drops.Topical application of mK5 eye drops can prevent corneal graft rejection and corneal neovascularization in rats.

In this study, YSZ thin films with different Y2O3 content have been prepared by electron beam evaporation on different types of substrates. The film properties such as surface roughness, microstructure, refractive index and transmission spectra were characterized by using Scanning Probe Microscopy (SPM), X-ray diffraction, SEM, ellipsometer and spectrophotometer respectively. The results indicate that the film properties and microstructure correlate with the annealing process dramatically. It is found the film structure undergoes from amorphous to tetragonal phase then ultimately to tetragonal and monoclinic phase with the temperature increasing from 100 to 1100°C, while the surface roughness increases from 1.3 to 24.6nm, and the refractive index varies from 1.86 to 2.02. XRD analysis shows the grain size increased with the annealing temperature, the reduction of defect and surface compact incurred by the high temperature process results in the increase of refractive index. Further investigations show that the optical properties of YSZ films have little effect with the content of Y2O3 and the variation of refractive index is caused by the compactness due to the crystallization of the films under high temperature.