Hybrid composite materials combine different fibers in preform and take advantages of different mechanical behaviors for improving ballistic impact damage tolerances.Here we report ballistic impact damages of plain-wo...Hybrid composite materials combine different fibers in preform and take advantages of different mechanical behaviors for improving ballistic impact damage tolerances.Here we report ballistic impact damages of plain-woven laminates with different hybrids and stacking sequences.Three kinds of hybrid laminates,i.e.,carbon/Kevlar,carbon/ultra-high molecular weight polyethylene(UHMWPE),and UHMWPE/Kevlar,had been prepared and tested in ballistic penetration with fragment simulating projectiles(FSP).The residual velocities of the projectiles and impact damage morphologies of the laminates have been obtained to show impact energy absorptions for the different hybrid schemes.A microstructural model of the hybrid laminates had also been established to show impact damage mechanisms with finite element analysis(FEA).We found that the UHMWPE/Kevlar hybrid laminates with Kevlar layers as the front face have the highest energy absorption capacity,followed by the carbon/Kevlar hybrid laminates with carbon layers as the front face.The main damage modes are fiber breakages,matrix crack and interlayer delamination.The ballistic damage evolutions from the FEA results show that the major damage is shear failure for front layers,while tension failure for the back layers.We expect that the ballistic impact performance could be improved from the different hybrid schemes.展开更多
AIM:To investigate the mechanisms by which Cskbinding protein(CBP)inhibits tumor progression in esophageal carcinoma.METHODS:A CBP overexpressing esophageal carcinoma cell line(TE-1)was established.The growth,invasion...AIM:To investigate the mechanisms by which Cskbinding protein(CBP)inhibits tumor progression in esophageal carcinoma.METHODS:A CBP overexpressing esophageal carcinoma cell line(TE-1)was established.The growth,invasion,and migration of CBP-TE-1 cells,as well as the expression of Src were then determined and compared with those in normal TE-1 cells.RESULTS:The expression of Src was decreased by the overexpression of CBP in TE-1 cells.The growth,invasion,and migration of TE-1 cells were decreased by the overexpression of CBP.CONCLUSION:This study indicates that CBP may decrease the metastasis of esophageal carcinoma by inhibiting the activation of Src.CBP may be a potential tumor suppressor and targeting the CBP gene may be an alternative strategy for the development of therapies for esophageal carcinoma.展开更多
Three pairs of specific primers were designed to amplify the F2-1, F2-2 and XF2-2 truncated sequences of ORF2 which encodes the capsid protein of porcine circovirus type 2 (PCV-2). The F2-1 sequence had most of the ...Three pairs of specific primers were designed to amplify the F2-1, F2-2 and XF2-2 truncated sequences of ORF2 which encodes the capsid protein of porcine circovirus type 2 (PCV-2). The F2-1 sequence had most of the NLS region of ORF2, but the F2-2 and XF2-2 genes had the NLS region deleted. Truncated genes were subcloned into pET-32a(+) vectors to construct recombinant fusion expression vectors. The vectors were then transformed into Rosetta(DE3) E. coli and expressed by induction of IPTG. Expressed proteins were detected by western blotting and ELISA. The protein with best immunoreactivity was confirmed and selected, then utilized to inoculate SPF rabbits to prepare polyclonal antibodies. The protein and prepared polyclonal antibody were utilized to detect sera samples against PCV-2 from Shandong province and PCV-2 particles in PK-15 cells. In our study, three recombinant fusion proteins were successfully obtained, and the molecular weights of fusion proteins were 35.9 kDa, 33.6 kDa and 38.6 kDa respectively detected by SDS-PAGE. All of the proteins showed positive reaction with anti-PCV-2 antisera, and His-XF2-2 showed better immunoreactivity than the others. The protein of His-XF2-2 was coated as antigen in ELISA to detect the seroprevalence of PCV-2 in certain districts of Shandong province, the seropositivity rate was 27.7 % (73/264). Specific fluorescence and positive signals for PCV-2 could be detected in PK-15 cells inoculated with PCV-2 with the participation of prepared antibodies against His-XF2-2 in IFA and IPMA. Experimental results indicated that the truncated PCV-20RF2 gene containing most of the NLS region was successfully expressed in E. coli, and His-XF2-2 was demonstrated to have better immunoreactivity with anti-PCV-2 antisera than the other two fusion proteins. His-XF2-2 and prepared polyclonal antibodies against it had a satisfactory capability in detecting PCV-2 infection.展开更多
Power Quality (PQ) combined disturbances become common along with ubiquity of voltage flickers and harmonics. This paper presents a novel approach to classify the different patterns of PQ combined disturbances. The cl...Power Quality (PQ) combined disturbances become common along with ubiquity of voltage flickers and harmonics. This paper presents a novel approach to classify the different patterns of PQ combined disturbances. The classification system consists of two parts, namely the feature extraction and the automatic recognition. In the feature extraction stage, Phase Space Reconstruction (PSR), a time series analysis tool, is utilized to construct disturbance signal trajectories. For these trajectories, several indices are proposed to form the feature vectors. Support Vector Machines (SVMs) are then implemented to recognize the different patterns and to evaluate the efficiencies. The types of disturbances discussed include a combination of short-term dis-turbances (voltage sags, swells) and long-term disturbances (flickers, harmonics), as well as their homologous single ones. The feasibilities of the proposed approach are verified by simulation with thousands of PQ events. Comparison studies based on Wavelet Transform (WT) and Artificial Neural Network (ANN) are also reported to show its advantages.展开更多
We demonstrate that the etalon effects of alkali cells can be used as the output coupler of an alkali laser.Based on a rubidium cell with highly parallelized windows,a 2.7 W rubidium laser with optical efficiency of 2...We demonstrate that the etalon effects of alkali cells can be used as the output coupler of an alkali laser.Based on a rubidium cell with highly parallelized windows,a 2.7 W rubidium laser with optical efficiency of 20.9%and slope efficiency of 31.8%is obtained by adopting unconventional output couplers.Since it has compact configuration and the inner surface of the rubidium cell is uncoated,this may be used in high power laser systems with long lifetimes.展开更多
BACKGROUND Glycated albumin(GA),the non-enzymatic glycation product of albumin in plasma,became a glycemic marker in the beginning of the 21st century.The assay is not affected by hemoglobin levels and reflects the gl...BACKGROUND Glycated albumin(GA),the non-enzymatic glycation product of albumin in plasma,became a glycemic marker in the beginning of the 21st century.The assay is not affected by hemoglobin levels and reflects the glycemic status over a shorter period as compared to HbA1c measurements.Thus,GA may contributes as an intermediate glucose index in the current diabetes mellitus(DM)diagnostic system.AIM To search and summarize the available data on glycated albumin measurements required for the diagnosis of diabetes mellitus.METHODS Databases,including PubMed,Embase,Web of Science,and Cochrane Central Register of Controlled Trials(CENTRAL),among others,were systematically searched.The Quality Assessment of Diagnostic Accuracy Studies-2 tool was applied for the assessment of quality,and the bivariate model was used to pool the sensitivity and specificity.The hierarchical summary receiver operator characteristic curves(HSROC)model was utilized to estimate the summary receiver operating characteristics curve(SROC).Sensitivity analysis was performed to investigate the association of the study design and patient characteristics with the test accuracy and meta-regression to find the source of heterogeneity.RESULTS Three studies regarding gestational diabetes mellitus(GDM)and a meta-analysis of 16 non-GDM studies,comprising a total sample size of 12876,were included in the work.Results reveal that the average cut-off values of GA reported for the diagnosis of GDM diagnosis was much lower than those for non-GDM.For non-GDM cases,diagnosing DM with a circulating GA cut-off of 14.0%had a sensitivity of 0.766(95%CI:0.539,0.901),specificity of 0.687(95%CI:0.364,0.894),and area under the curve of 0.80(95%CI:0.76,0.83)for the SROC.The estimated SROC at different GA cut-off values for non-GDM exhibited that the average location parameter lambda of 16 non-GDM studies was 2.354(95%CI:2.002,2.707),and the scale parameter beta was-0.163(95%CI:-0.614,0.288).These non-GDM studies with various thresholds had substantial heterogeneity,which may be attributed to the type of DM,age,and body mass index as possible sources.CONCLUSION Glycated albumin in non-DM exhibits a moderate diagnostic accuracy.Further research on the diagnostic accuracy of GA for GDM and combinational measurements of GA and other assays is suggested.展开更多
The extinction ratio and insertion loss of spatial light modulator are subject to the material problem, thus limiting its applications. One reflection-type silicon-based spatial light modulator with high reflective ma...The extinction ratio and insertion loss of spatial light modulator are subject to the material problem, thus limiting its applications. One reflection-type silicon-based spatial light modulator with high reflective materials outside the Fabry-Perot cavity is demonstrated in this paper. The reflectivity values of the outside-cavity materials with different film layer numbers are simulated. The reflectivity values of 6-pair Ta2O5/SiO2 films at 1550 nm are experimentally verified to be as high as 99.9%. The surfaces of 6-pair Ta2O5/SiO2 films are smooth: their root-mean-square roughness values are as small as 0.53 nm. The insertion loss of the device at 1550 nm is only 1.2 dB. The high extinction ratio of the device at 1550 nm and 11 V is achieved to be 29.7 dB. The spatial light modulator has a high extinction ratio and low insertion loss for applications.展开更多
In this work, a dual-side parabolic structural(DSPS) multimode interference(MMI) thermo–optic(TO) waveguide switch is designed and fabricated by using novel low-loss fluorinated photopolymer materials. Comparing with...In this work, a dual-side parabolic structural(DSPS) multimode interference(MMI) thermo–optic(TO) waveguide switch is designed and fabricated by using novel low-loss fluorinated photopolymer materials. Comparing with the traditional dual-side linear structural(DSLS) MMI device, the effective length of the MMI coupling region proposed can be effectively reduced by 40%. The thermal stability of the waveguide material is analyzed, and the optical characteristics of the switching chip are simulated. The actual performances of the entire MMI switch are measured with an insertion loss of7 dB, switching power of 15 m W and an extinction ratio of 28 dB. In contrast to the traditional MMI optical switch, the new type of parabolic structural MMI TO waveguide switch exhibits lower power consumption and larger extinction ratio. The compact fluorinated polymer MMI TO switches are suitable well for realizing miniaturization, high-properties, and lower cost of photonic integrated circuits.展开更多
目的:观察玻璃体腔注射康柏西普治疗增殖性糖尿病视网膜病变(PDR)患者玻璃体切除术后迟发性玻璃体出血(POVCH)的效果。方法:回顾性分析。纳入PDR患者玻璃体术后发生POVCH患者56例57眼,其中康柏西普组28眼行玻璃体腔内注射0.05mL康柏西普...目的:观察玻璃体腔注射康柏西普治疗增殖性糖尿病视网膜病变(PDR)患者玻璃体切除术后迟发性玻璃体出血(POVCH)的效果。方法:回顾性分析。纳入PDR患者玻璃体术后发生POVCH患者56例57眼,其中康柏西普组28眼行玻璃体腔内注射0.05mL康柏西普,对照组29眼不进行玻璃体腔内注射康柏西普,观察或使用口服药物治疗。记录患者玻璃体切除前后、玻璃体腔注药前后、POVCH后1mo时及随访结束时最佳矫正视力(BCVA)、玻璃体积血分级、眼压、眼底情况及再次手术(玻璃体腔灌术)情况。并观察POVCH发生时患者血糖、血压及心理等全身情况。结果:POVCH后1mo时,康柏西普组的BCVA优于对照组(1.26±0.13 vs 1.76±0.20;P=0.04),POVCH发生时及随访结束时两组BCVA无统计学差异(P=0.08,0.24)。玻璃体积血混浊改善程度:康柏西普组显效13眼,有效9眼,无效6眼;对照组显效11眼,有效3眼,无效15眼,差异有统计学意义(P=0.03)。康柏西普组POVCH眼再次手术率低于对照组(21%vs 51%,P=0.045)。康柏西普组平均玻璃体注药次数为2.24±1.16(1~5)次。随访12~24(平均16.47±3.34)mo。POVCH发生的28眼中,发现眼底纤维血管膜11眼(19%),视网膜新生血管11眼(19%),新生血管性青光眼10眼(18%),虹膜新生血管4眼(7%)。POVCH出血吸收后补充视网膜光凝44眼(77%)。POVCH发生时患者血糖和(或)糖化血红蛋白高、血压异常者43例(75%),情绪激动或劳累者6例(11%)。结论:玻璃体腔内注射康柏西普可促进PDR患者POVCH积血吸收,提高视力,降低再次玻璃体切除手术的几率,同时也应注意严格控制PDR患者的血糖、血压、精神心理等全身因素。展开更多
Objective To detect cadmium in environmental and food samples by graphite furnace atomic absorption spectroscopy (GFAAS) and inductively coupled plasma atomic emission spectroscopy (ICPAES). Methods An indirect co...Objective To detect cadmium in environmental and food samples by graphite furnace atomic absorption spectroscopy (GFAAS) and inductively coupled plasma atomic emission spectroscopy (ICPAES). Methods An indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) was developed based on a cadmium-specific monoclonal antibody. IC-ELISA for cadmium in environmental and food samples was evaluated. Results IC-ELISA showed an IC50 of 45.6 μg/L with a detection limit of 1.95 μg/L for cadmium, and showed a mean recovery ranging 97.67%-107.08%. The coefficient of variations for intra- and interassay was 3.41%-6.61% and 4.70%-9.21%, respectively. The correlation coefficient between IC-ELISA and GFAAS was 0.998. Conclusion IC-ELISA can detect and quantify cadmium residue in environmental or food samples.展开更多
The structure genes spike(S) ,nucleocapsid(N) ,membrane(M) ,small membrane(sM) of a porcine epidemic diarrhea virus(PEDV) strain DX isolated in Gansu province,North-west of China,were cloned,sequenced and compared wit...The structure genes spike(S) ,nucleocapsid(N) ,membrane(M) ,small membrane(sM) of a porcine epidemic diarrhea virus(PEDV) strain DX isolated in Gansu province,North-west of China,were cloned,sequenced and compared with published sequences of PEDV strains. The nucleotide sequences encoding the entire S,sM,M and N genes open reading frame(ORF) of DX were 4 152,231,681 and 1 326 bases long respectively. There were transcription regulatory sequences(TRSs) upstream of the initiator ATG of the S,N and M genes. The amino acids sequences of S,M and N contained 30,3 and 7 potential asparagine(N) -linked glycosylation sites. Homologous analysis and phylogenetic trees showed that DX had the closest relationship with strains LJB/06,JS-2004-2Z and CH/HLJH/06 that were also isolated from China and indicated the prevalence of some PEDV isolates in China were widespread since the JS-2004-2Z strain originated from the south of the China,and LJB/06 and CH/HLJH/06 were isolated from northeast China. The N gene was cloned using two primers which contained Nco I and BamH I restriction enzyme sites and subcloned into expression vector pET30a. The recombinant plasmid was then transformed into E.coli Rossta. SDS-PAGE showed there was a protein of about 55kDa as expected and Western blot indicated the N protein had biological activity.展开更多
The complete genome sequence of transmissible Gastroenteritis virus (TGEV) strain TS, previously isolated from Gansu province, was cloned and compared with published sequence data from other TGEV strains. Phylogenetic...The complete genome sequence of transmissible Gastroenteritis virus (TGEV) strain TS, previously isolated from Gansu province, was cloned and compared with published sequence data from other TGEV strains. Phylogenetic tree analysis based on the amino acid and nucleotide sequences of the S gene showed that the TGEV strains were divided into 3 clusters. TGEV TS showed a close evolutionary relationship to the American Miller cluster but had a 5' non-translated region (NTR) sequence closely related to the American Purdue cluster. Continued culture in different cell types indicated that TGEV TS virulence could be attenuated after fifty passages in Porcine kidney (PK-15) cells, and that the Porcine kidney cell line IB-RS-2 (IBRS) was not suitable for culture of the TGEV strain TS.展开更多
Deep-water deposition is a current issue in sedimentological research. Sandy-debris-flow sandstones and turbidity-current sandstones are the main types of sandstone that are the focus of considerable disputes in this ...Deep-water deposition is a current issue in sedimentological research. Sandy-debris-flow sandstones and turbidity-current sandstones are the main types of sandstone that are the focus of considerable disputes in this research. Previous studies mainly focused on description of the macroscopic sedimentary structure and theoretical derivation of the formation mechanisms. The microscopic petrological characteristics, reservoir properties, and formation mechanisms of deep-water sandy-debris-flow and turbidity-current sandstones have been studied in the Yanchang Formation of the Ordos Basin,China, by means of field outcrop surveys, thin-section identification, geochemical element analysis, and porosity and permeability measurements under overburden pressure. The content of detrital grains in the sandy-debris-flow sandstones is high, whereas the contents of mica sheets and matrix are low. The fine-grained matrix is distributed unevenly within the pores. A considerable number of residual intergranular pores are preserved in the middle of single sand bodies, resulting in relatively better reservoir properties. The total number of detrital grains in the turbidite sandstone is low, while it contains abundant mica sheets and matrix. The mica sheets and fine-grained matrix are distributed evenly within the pores, resulting in serious damage to pores and poor reservoir properties. The sandy-debris-flow sandstones in the center of the lake basin form a high-quality reservoir; thus, this area is suitable for oil and gas exploration.展开更多
OBJECTIVE To use network pharmacology to predict and analyze the mechanism of Aconite-Ginger against myocardial ischemia.METHODS TCMSP was used to collect the active compounds of Aconite-Ginger and predict the targets...OBJECTIVE To use network pharmacology to predict and analyze the mechanism of Aconite-Ginger against myocardial ischemia.METHODS TCMSP was used to collect the active compounds of Aconite-Ginger and predict the targets of active compounds.At the same time,target sites of anti-myocardial ischemic injury drugs were collected using DisGeNET and CTD database,and then active compounds and target sites were compared.Analyze and screen out the targets of AconiteGinger anti-cardiac machine ischemia.GO,KEGG analysis and Aconite-Ginger drug molecule-target were performed on selected targets using MAS 3.0 and Cytoscape 3.3.0 software.RESULTS 27 common targets of Aconite-Ginger anti-ischemia ischemia and 63 signal pathways were predicted.CONCLUSION Aconite-Ginger mainly regulates calcium signal transduction,apoptosis and MAPK signaling pathway,which can also regulate through toll-like receptors,Fc epsilon RI and other signal pathways,so it is speculated that it may participate in regulation Apoptosis,inflammatory response,enhancement of myocardial function,etc.,thereby exerting an anti-ischemic effect.It laid a good foundation for further revealing its mechanism of action.展开更多
AIM:To establish an easily-handled method to isolate mesenchymal stem cells(MSCs) from coagulated human bone marrow samples. METHODS: Thrombin was added to aliquots of seven heparinized human bone marrow samples to mi...AIM:To establish an easily-handled method to isolate mesenchymal stem cells(MSCs) from coagulated human bone marrow samples. METHODS: Thrombin was added to aliquots of seven heparinized human bone marrow samples to mimic marrow coagulation. The clots were untreated,treated with urokinase or mechanically cut into pieces before culture for MSCs. The un-coagulated samples and the clots were also stored at 4 ℃ for 8 or 16 h before the treatment. The numbers of colony-forming unit-fibroblast(CFU-F) in the different samples were determined. The adherent cells from different groups were passaged and their surface profile was analyzed with flow cytometry. Their capacities of in vitro osteogenesis and adipogenesis were observed after the cells were exposed to specific inductive agents.RESULTS: The average CFU-F number of urokinasetreated samples(16.85 ± 11.77/106) was comparable to that of un-coagulated control samples(20.22 ± 10.65/106,P = 0.293),which was significantly higher than those of mechanically-cut clots(6.5 ± 5.32/106,P < 0.01) and untreated clots(1.95 ± 1.86/106,P < 0.01). The CFU-F numbers decreased after samples were stored,but those of control and urokinase-treated clots remained higher than the other two groups. Consistently,the numbers of the attached cells at passage 0 were higher in control and urokinase-treated clots than those of mechanically-cut clots and untreated clots.The attached cells were fibroblast-like in morphology and homogenously positive for CD44,CD73 and CD90,and negative for CD31 and CD45. Also,they could be induced to differentiate into osteoblasts and adipocytes in vitro. CONCLUSION: Urokinase pretreatment is an optimal strategy to isolate MSCs from human bone marrow samples that are poorly aspirated and clotted.展开更多
An explanation of optical unitary transformation is presented for general nonoverlapping-image multimode interference(MMI)couplers with any number of input and output ports.The light transformation in the MMI coupler ...An explanation of optical unitary transformation is presented for general nonoverlapping-image multimode interference(MMI)couplers with any number of input and output ports.The light transformation in the MMI coupler can be considered as an optical field matrix acting on an input light column vector.We investigate the general phase principle of output light image.The complete proof of nonoverlapping-image MMI coupler’s optical unitarity along with the phase analysis of matrix element is provided.Based on a two-dimensional finite-difference time-domain(2 D-FDTD)simulation,the unitary transformation is obtained for a 4×4 nonoverlapping-image MMI coupler within a deviation of 4×10-2 for orthogonal invariance and 8×10-2 for transvection invariance in the C-band spectral range.A compact 1×4 splitter based on cascaded MMI coupler is proposed,showing a phase deviation less than 5.4°while maintaining a low-loss performance in C-band spectra.展开更多
Objective: To evaluate the assessment of intracranial hypertension and nerve injury in patients with hypertensive cerebral hemorrhage by transcranial Doppler (TCD). Methods: The patients who were hospitalized for hype...Objective: To evaluate the assessment of intracranial hypertension and nerve injury in patients with hypertensive cerebral hemorrhage by transcranial Doppler (TCD). Methods: The patients who were hospitalized for hypertensive cerebral hemorrhage between August 2014 and February 2017 were selected as the cerebral hemorrhage group and healthy subjects who received physical examination during the same period were selected as the control group;TCD was used to determine the PI of affected-side and unaffected-side middle cerebral artery in cerebral hemorrhage group and lumbar puncture was done to measure intracranial pressure. The serum was collected from the two groups to detect the levels of inflammatory cytokines and nerve injury markers. Results: PI level in affected-side middle cerebral artery of cerebral hemorrhage group was significantly higher than that in the unaffected-side and positively correlated with intracranial pressure level;serum IL-1β, TNF-α, ICAM-1, MMP9, YKL-40, Asp, Glu, NPY, NSE and GFAP levels of cerebral hemorrhage group were significantly higher than those of control group, and serum IL-1β, TNF-α, ICAM-1, MMP9, YKL-40, Asp, Glu, NPY, NSE and GFAP levels of cerebral hemorrhage group of patients with high PI level were significantly higher than those of cerebral hemorrhage group of patients with low PI level. Conclusion: TCD parameters can evaluate the degree of intracranial pressure increase and nerve injury in patients with hypertensive cerebral hemorrhage.展开更多
Background: The radiochemotherapy regimen concomitantly employing temozolomide (TMZ) chemotherapy and radiotherapy (RT) 4 weeks after surgery, followed by 6 cycles of TMZ is a common treatment for glioblastoma (...Background: The radiochemotherapy regimen concomitantly employing temozolomide (TMZ) chemotherapy and radiotherapy (RT) 4 weeks after surgery, followed by 6 cycles of TMZ is a common treatment for glioblastoma (GBM). However, its median overall survival (OS) is only 14.6 months. This study was to explore the effectiveness and safety of early TMZ chemotherapy between surgery and chemoradiotherapy plus the standard concomitant radiochemotherapy regimen. Methods: A randomized, parallel group, open-label study of 99 newly diagnosed GBM patients was conducted at 10 independent Chinese neurosurgical departments from June 2008 to June 2012. Patients were treated with concomitant radiochemotherapy regimen plus early postsurgical temozolomide (early TMZ group) or standard concomitant radiochemotherapy regimen (control group). Overall response was assessed based on objective tumor assessments, administration ofcorticosteroid and neurological status test. Hematological, biochemical, laboratory, adverse event (AE), and neurological condition were measured for 24 months of tbllow-up. The primary efficacy endpoint of this study was overall survival (OS). The secondary endpoint was progression free survival (PFS). Results: The median OS time in the early TMZ group was 17.6 months, compared with 13.2 months in the control group (log-rank test P 0.021 ). In addition, the OS rate in the early TMZ group was higher at 6, 12, and 18 months than in the control group, respectively (P 〈 0.05). The median PFS time was 8.7 months in the early TMZ group and 10.4 months in the control group (log-rank test P = 0.695). AEs occurred in 29 (55.8%) and 31(73.8%) patients respectively in early and control groups, including nausea (15.4% vs. 33.3%), vomiting (7.7% vs. 28.6%), fever (7.7% vs. 11.9%), and headache (3.8% vs. 23.8%). Only 30.8% and 33.3% were drug-related, respectively. Conclusions: Addition of TMZ chemotherapy in the early break of the standard concomitant radiochemotherapy regimen was well tolerated and significantly improved the OS of the GBM patients, compared with standard concomitant radiochemotherapy regimen. However, a larger randomized trial is warranted to verify these results.展开更多
SO2, NO2, and PM10 are the major outdoor air pollutants in China, and most of the cities in China have regulatory monitoring sites for these three air pollutants. In this study, we developed a land use regression (LUR...SO2, NO2, and PM10 are the major outdoor air pollutants in China, and most of the cities in China have regulatory monitoring sites for these three air pollutants. In this study, we developed a land use regression (LUR) model using regulatory monitoring data to predict the spatial distribution of air pollutant concentrations in Jinan, China. Traffic, land use and census data, and meteorological and physical conditions were included as candidate independent variables, and were tabulated for buffers of varying radii. SO2, NO2, and PM10 concentrations were most highly correlated with the area of industrial land within a buffer of 0.5 km (R2=0.34), the distance from an expressway (R2=0.45), and the area of residential land within a buffer of 1.5 km (R2=0.25), respectively. Three multiple linear regression (MLR) equations were established based on the most significant variables (p<0.05) for SO2, NO2, and PM10, and R2 values obtained were 0.617, 0.640, and 0.600, respectively. An LUR model can be applied to an area with complex terrain. The buffer radii of independent variables for SO2, NO2, and PM10 were chosen to be 0.5, 2, and 1.5 km, respectively based on univariate models. Intercepts of MLR equations can reflect the background concentrations in a certain area, but in this study the intercept values seemed to be higher than background concentrations. Most of the cities in China have a network of regulatory monitoring sites. However, the number of sites has been limited by the level of financial support available. The results of this study could be helpful in promoting the application of LUR models for monitoring pollutants in Chinese cities.展开更多
文摘Hybrid composite materials combine different fibers in preform and take advantages of different mechanical behaviors for improving ballistic impact damage tolerances.Here we report ballistic impact damages of plain-woven laminates with different hybrids and stacking sequences.Three kinds of hybrid laminates,i.e.,carbon/Kevlar,carbon/ultra-high molecular weight polyethylene(UHMWPE),and UHMWPE/Kevlar,had been prepared and tested in ballistic penetration with fragment simulating projectiles(FSP).The residual velocities of the projectiles and impact damage morphologies of the laminates have been obtained to show impact energy absorptions for the different hybrid schemes.A microstructural model of the hybrid laminates had also been established to show impact damage mechanisms with finite element analysis(FEA).We found that the UHMWPE/Kevlar hybrid laminates with Kevlar layers as the front face have the highest energy absorption capacity,followed by the carbon/Kevlar hybrid laminates with carbon layers as the front face.The main damage modes are fiber breakages,matrix crack and interlayer delamination.The ballistic damage evolutions from the FEA results show that the major damage is shear failure for front layers,while tension failure for the back layers.We expect that the ballistic impact performance could be improved from the different hybrid schemes.
基金Supported by Gansu Provincial Natural Science Foundation,No.1308RJZA188the Fundamental Research Funds for the Central Universities,No.lzujbky-2011-T03-16
文摘AIM:To investigate the mechanisms by which Cskbinding protein(CBP)inhibits tumor progression in esophageal carcinoma.METHODS:A CBP overexpressing esophageal carcinoma cell line(TE-1)was established.The growth,invasion,and migration of CBP-TE-1 cells,as well as the expression of Src were then determined and compared with those in normal TE-1 cells.RESULTS:The expression of Src was decreased by the overexpression of CBP in TE-1 cells.The growth,invasion,and migration of TE-1 cells were decreased by the overexpression of CBP.CONCLUSION:This study indicates that CBP may decrease the metastasis of esophageal carcinoma by inhibiting the activation of Src.CBP may be a potential tumor suppressor and targeting the CBP gene may be an alternative strategy for the development of therapies for esophageal carcinoma.
基金supported by the special studies for social welfare researches in institutes (2005DIB4J041)
文摘Three pairs of specific primers were designed to amplify the F2-1, F2-2 and XF2-2 truncated sequences of ORF2 which encodes the capsid protein of porcine circovirus type 2 (PCV-2). The F2-1 sequence had most of the NLS region of ORF2, but the F2-2 and XF2-2 genes had the NLS region deleted. Truncated genes were subcloned into pET-32a(+) vectors to construct recombinant fusion expression vectors. The vectors were then transformed into Rosetta(DE3) E. coli and expressed by induction of IPTG. Expressed proteins were detected by western blotting and ELISA. The protein with best immunoreactivity was confirmed and selected, then utilized to inoculate SPF rabbits to prepare polyclonal antibodies. The protein and prepared polyclonal antibody were utilized to detect sera samples against PCV-2 from Shandong province and PCV-2 particles in PK-15 cells. In our study, three recombinant fusion proteins were successfully obtained, and the molecular weights of fusion proteins were 35.9 kDa, 33.6 kDa and 38.6 kDa respectively detected by SDS-PAGE. All of the proteins showed positive reaction with anti-PCV-2 antisera, and His-XF2-2 showed better immunoreactivity than the others. The protein of His-XF2-2 was coated as antigen in ELISA to detect the seroprevalence of PCV-2 in certain districts of Shandong province, the seropositivity rate was 27.7 % (73/264). Specific fluorescence and positive signals for PCV-2 could be detected in PK-15 cells inoculated with PCV-2 with the participation of prepared antibodies against His-XF2-2 in IFA and IPMA. Experimental results indicated that the truncated PCV-20RF2 gene containing most of the NLS region was successfully expressed in E. coli, and His-XF2-2 was demonstrated to have better immunoreactivity with anti-PCV-2 antisera than the other two fusion proteins. His-XF2-2 and prepared polyclonal antibodies against it had a satisfactory capability in detecting PCV-2 infection.
基金Project (No. 50437010) supported by the Key Program of the Na-tional Natural Science Foundation of China
文摘Power Quality (PQ) combined disturbances become common along with ubiquity of voltage flickers and harmonics. This paper presents a novel approach to classify the different patterns of PQ combined disturbances. The classification system consists of two parts, namely the feature extraction and the automatic recognition. In the feature extraction stage, Phase Space Reconstruction (PSR), a time series analysis tool, is utilized to construct disturbance signal trajectories. For these trajectories, several indices are proposed to form the feature vectors. Support Vector Machines (SVMs) are then implemented to recognize the different patterns and to evaluate the efficiencies. The types of disturbances discussed include a combination of short-term dis-turbances (voltage sags, swells) and long-term disturbances (flickers, harmonics), as well as their homologous single ones. The feasibilities of the proposed approach are verified by simulation with thousands of PQ events. Comparison studies based on Wavelet Transform (WT) and Artificial Neural Network (ANN) are also reported to show its advantages.
基金Supported by the National Natural Science Foundation of China under Grant Nos.61875198 and 61775215the Foundation of Military Commission of Science and Technology of China under Grant No.61404140107。
文摘We demonstrate that the etalon effects of alkali cells can be used as the output coupler of an alkali laser.Based on a rubidium cell with highly parallelized windows,a 2.7 W rubidium laser with optical efficiency of 20.9%and slope efficiency of 31.8%is obtained by adopting unconventional output couplers.Since it has compact configuration and the inner surface of the rubidium cell is uncoated,this may be used in high power laser systems with long lifetimes.
文摘BACKGROUND Glycated albumin(GA),the non-enzymatic glycation product of albumin in plasma,became a glycemic marker in the beginning of the 21st century.The assay is not affected by hemoglobin levels and reflects the glycemic status over a shorter period as compared to HbA1c measurements.Thus,GA may contributes as an intermediate glucose index in the current diabetes mellitus(DM)diagnostic system.AIM To search and summarize the available data on glycated albumin measurements required for the diagnosis of diabetes mellitus.METHODS Databases,including PubMed,Embase,Web of Science,and Cochrane Central Register of Controlled Trials(CENTRAL),among others,were systematically searched.The Quality Assessment of Diagnostic Accuracy Studies-2 tool was applied for the assessment of quality,and the bivariate model was used to pool the sensitivity and specificity.The hierarchical summary receiver operator characteristic curves(HSROC)model was utilized to estimate the summary receiver operating characteristics curve(SROC).Sensitivity analysis was performed to investigate the association of the study design and patient characteristics with the test accuracy and meta-regression to find the source of heterogeneity.RESULTS Three studies regarding gestational diabetes mellitus(GDM)and a meta-analysis of 16 non-GDM studies,comprising a total sample size of 12876,were included in the work.Results reveal that the average cut-off values of GA reported for the diagnosis of GDM diagnosis was much lower than those for non-GDM.For non-GDM cases,diagnosing DM with a circulating GA cut-off of 14.0%had a sensitivity of 0.766(95%CI:0.539,0.901),specificity of 0.687(95%CI:0.364,0.894),and area under the curve of 0.80(95%CI:0.76,0.83)for the SROC.The estimated SROC at different GA cut-off values for non-GDM exhibited that the average location parameter lambda of 16 non-GDM studies was 2.354(95%CI:2.002,2.707),and the scale parameter beta was-0.163(95%CI:-0.614,0.288).These non-GDM studies with various thresholds had substantial heterogeneity,which may be attributed to the type of DM,age,and body mass index as possible sources.CONCLUSION Glycated albumin in non-DM exhibits a moderate diagnostic accuracy.Further research on the diagnostic accuracy of GA for GDM and combinational measurements of GA and other assays is suggested.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61575076 and 61804148)the National Key Research and Development Plan of China(Grant No.2016YFB0402502)
文摘The extinction ratio and insertion loss of spatial light modulator are subject to the material problem, thus limiting its applications. One reflection-type silicon-based spatial light modulator with high reflective materials outside the Fabry-Perot cavity is demonstrated in this paper. The reflectivity values of the outside-cavity materials with different film layer numbers are simulated. The reflectivity values of 6-pair Ta2O5/SiO2 films at 1550 nm are experimentally verified to be as high as 99.9%. The surfaces of 6-pair Ta2O5/SiO2 films are smooth: their root-mean-square roughness values are as small as 0.53 nm. The insertion loss of the device at 1550 nm is only 1.2 dB. The high extinction ratio of the device at 1550 nm and 11 V is achieved to be 29.7 dB. The spatial light modulator has a high extinction ratio and low insertion loss for applications.
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0402502)the National Natural Science Foundation of China(Grant Nos.61575076,61475061,61605057,and 61675087)the Jilin Provincial Industrial Innovation Special Fund Project,China(Grant No.2016C019)
文摘In this work, a dual-side parabolic structural(DSPS) multimode interference(MMI) thermo–optic(TO) waveguide switch is designed and fabricated by using novel low-loss fluorinated photopolymer materials. Comparing with the traditional dual-side linear structural(DSLS) MMI device, the effective length of the MMI coupling region proposed can be effectively reduced by 40%. The thermal stability of the waveguide material is analyzed, and the optical characteristics of the switching chip are simulated. The actual performances of the entire MMI switch are measured with an insertion loss of7 dB, switching power of 15 m W and an extinction ratio of 28 dB. In contrast to the traditional MMI optical switch, the new type of parabolic structural MMI TO waveguide switch exhibits lower power consumption and larger extinction ratio. The compact fluorinated polymer MMI TO switches are suitable well for realizing miniaturization, high-properties, and lower cost of photonic integrated circuits.
文摘目的:观察玻璃体腔注射康柏西普治疗增殖性糖尿病视网膜病变(PDR)患者玻璃体切除术后迟发性玻璃体出血(POVCH)的效果。方法:回顾性分析。纳入PDR患者玻璃体术后发生POVCH患者56例57眼,其中康柏西普组28眼行玻璃体腔内注射0.05mL康柏西普,对照组29眼不进行玻璃体腔内注射康柏西普,观察或使用口服药物治疗。记录患者玻璃体切除前后、玻璃体腔注药前后、POVCH后1mo时及随访结束时最佳矫正视力(BCVA)、玻璃体积血分级、眼压、眼底情况及再次手术(玻璃体腔灌术)情况。并观察POVCH发生时患者血糖、血压及心理等全身情况。结果:POVCH后1mo时,康柏西普组的BCVA优于对照组(1.26±0.13 vs 1.76±0.20;P=0.04),POVCH发生时及随访结束时两组BCVA无统计学差异(P=0.08,0.24)。玻璃体积血混浊改善程度:康柏西普组显效13眼,有效9眼,无效6眼;对照组显效11眼,有效3眼,无效15眼,差异有统计学意义(P=0.03)。康柏西普组POVCH眼再次手术率低于对照组(21%vs 51%,P=0.045)。康柏西普组平均玻璃体注药次数为2.24±1.16(1~5)次。随访12~24(平均16.47±3.34)mo。POVCH发生的28眼中,发现眼底纤维血管膜11眼(19%),视网膜新生血管11眼(19%),新生血管性青光眼10眼(18%),虹膜新生血管4眼(7%)。POVCH出血吸收后补充视网膜光凝44眼(77%)。POVCH发生时患者血糖和(或)糖化血红蛋白高、血压异常者43例(75%),情绪激动或劳累者6例(11%)。结论:玻璃体腔内注射康柏西普可促进PDR患者POVCH积血吸收,提高视力,降低再次玻璃体切除手术的几率,同时也应注意严格控制PDR患者的血糖、血压、精神心理等全身因素。
基金supported by the Research Foundation of Science and Technology Project in Guangdong Province of China (No.2003C20409)Science and Technology Project in General Administration of Quality Supervision,Inspection and Quarantine of China(No. 2004IK062)
文摘Objective To detect cadmium in environmental and food samples by graphite furnace atomic absorption spectroscopy (GFAAS) and inductively coupled plasma atomic emission spectroscopy (ICPAES). Methods An indirect competitive enzyme-linked immunosorbent assay (IC-ELISA) was developed based on a cadmium-specific monoclonal antibody. IC-ELISA for cadmium in environmental and food samples was evaluated. Results IC-ELISA showed an IC50 of 45.6 μg/L with a detection limit of 1.95 μg/L for cadmium, and showed a mean recovery ranging 97.67%-107.08%. The coefficient of variations for intra- and interassay was 3.41%-6.61% and 4.70%-9.21%, respectively. The correlation coefficient between IC-ELISA and GFAAS was 0.998. Conclusion IC-ELISA can detect and quantify cadmium residue in environmental or food samples.
基金National Basic Research Program (2004CCA00500)National High-tech Development Research Program of China (2006AA02Z440)
文摘The structure genes spike(S) ,nucleocapsid(N) ,membrane(M) ,small membrane(sM) of a porcine epidemic diarrhea virus(PEDV) strain DX isolated in Gansu province,North-west of China,were cloned,sequenced and compared with published sequences of PEDV strains. The nucleotide sequences encoding the entire S,sM,M and N genes open reading frame(ORF) of DX were 4 152,231,681 and 1 326 bases long respectively. There were transcription regulatory sequences(TRSs) upstream of the initiator ATG of the S,N and M genes. The amino acids sequences of S,M and N contained 30,3 and 7 potential asparagine(N) -linked glycosylation sites. Homologous analysis and phylogenetic trees showed that DX had the closest relationship with strains LJB/06,JS-2004-2Z and CH/HLJH/06 that were also isolated from China and indicated the prevalence of some PEDV isolates in China were widespread since the JS-2004-2Z strain originated from the south of the China,and LJB/06 and CH/HLJH/06 were isolated from northeast China. The N gene was cloned using two primers which contained Nco I and BamH I restriction enzyme sites and subcloned into expression vector pET30a. The recombinant plasmid was then transformed into E.coli Rossta. SDS-PAGE showed there was a protein of about 55kDa as expected and Western blot indicated the N protein had biological activity.
基金National Basic Research Program(2004CCA00500)National High-tech Development Research Program of China (2006AA02Z440)
文摘The complete genome sequence of transmissible Gastroenteritis virus (TGEV) strain TS, previously isolated from Gansu province, was cloned and compared with published sequence data from other TGEV strains. Phylogenetic tree analysis based on the amino acid and nucleotide sequences of the S gene showed that the TGEV strains were divided into 3 clusters. TGEV TS showed a close evolutionary relationship to the American Miller cluster but had a 5' non-translated region (NTR) sequence closely related to the American Purdue cluster. Continued culture in different cell types indicated that TGEV TS virulence could be attenuated after fifty passages in Porcine kidney (PK-15) cells, and that the Porcine kidney cell line IB-RS-2 (IBRS) was not suitable for culture of the TGEV strain TS.
基金funded by the Natural Science Foundation of China(41772099)the National Science and Technology Major Project(2017ZX05001-003)
文摘Deep-water deposition is a current issue in sedimentological research. Sandy-debris-flow sandstones and turbidity-current sandstones are the main types of sandstone that are the focus of considerable disputes in this research. Previous studies mainly focused on description of the macroscopic sedimentary structure and theoretical derivation of the formation mechanisms. The microscopic petrological characteristics, reservoir properties, and formation mechanisms of deep-water sandy-debris-flow and turbidity-current sandstones have been studied in the Yanchang Formation of the Ordos Basin,China, by means of field outcrop surveys, thin-section identification, geochemical element analysis, and porosity and permeability measurements under overburden pressure. The content of detrital grains in the sandy-debris-flow sandstones is high, whereas the contents of mica sheets and matrix are low. The fine-grained matrix is distributed unevenly within the pores. A considerable number of residual intergranular pores are preserved in the middle of single sand bodies, resulting in relatively better reservoir properties. The total number of detrital grains in the turbidite sandstone is low, while it contains abundant mica sheets and matrix. The mica sheets and fine-grained matrix are distributed evenly within the pores, resulting in serious damage to pores and poor reservoir properties. The sandy-debris-flow sandstones in the center of the lake basin form a high-quality reservoir; thus, this area is suitable for oil and gas exploration.
基金supported by Shaanxi Provincial Administration of Traditional Chinese Medicine project(JCPT007)
文摘OBJECTIVE To use network pharmacology to predict and analyze the mechanism of Aconite-Ginger against myocardial ischemia.METHODS TCMSP was used to collect the active compounds of Aconite-Ginger and predict the targets of active compounds.At the same time,target sites of anti-myocardial ischemic injury drugs were collected using DisGeNET and CTD database,and then active compounds and target sites were compared.Analyze and screen out the targets of AconiteGinger anti-cardiac machine ischemia.GO,KEGG analysis and Aconite-Ginger drug molecule-target were performed on selected targets using MAS 3.0 and Cytoscape 3.3.0 software.RESULTS 27 common targets of Aconite-Ginger anti-ischemia ischemia and 63 signal pathways were predicted.CONCLUSION Aconite-Ginger mainly regulates calcium signal transduction,apoptosis and MAPK signaling pathway,which can also regulate through toll-like receptors,Fc epsilon RI and other signal pathways,so it is speculated that it may participate in regulation Apoptosis,inflammatory response,enhancement of myocardial function,etc.,thereby exerting an anti-ischemic effect.It laid a good foundation for further revealing its mechanism of action.
基金Supported by Natural Science Foundation of China,Nos.30971068 and 81170522
文摘AIM:To establish an easily-handled method to isolate mesenchymal stem cells(MSCs) from coagulated human bone marrow samples. METHODS: Thrombin was added to aliquots of seven heparinized human bone marrow samples to mimic marrow coagulation. The clots were untreated,treated with urokinase or mechanically cut into pieces before culture for MSCs. The un-coagulated samples and the clots were also stored at 4 ℃ for 8 or 16 h before the treatment. The numbers of colony-forming unit-fibroblast(CFU-F) in the different samples were determined. The adherent cells from different groups were passaged and their surface profile was analyzed with flow cytometry. Their capacities of in vitro osteogenesis and adipogenesis were observed after the cells were exposed to specific inductive agents.RESULTS: The average CFU-F number of urokinasetreated samples(16.85 ± 11.77/106) was comparable to that of un-coagulated control samples(20.22 ± 10.65/106,P = 0.293),which was significantly higher than those of mechanically-cut clots(6.5 ± 5.32/106,P < 0.01) and untreated clots(1.95 ± 1.86/106,P < 0.01). The CFU-F numbers decreased after samples were stored,but those of control and urokinase-treated clots remained higher than the other two groups. Consistently,the numbers of the attached cells at passage 0 were higher in control and urokinase-treated clots than those of mechanically-cut clots and untreated clots.The attached cells were fibroblast-like in morphology and homogenously positive for CD44,CD73 and CD90,and negative for CD31 and CD45. Also,they could be induced to differentiate into osteoblasts and adipocytes in vitro. CONCLUSION: Urokinase pretreatment is an optimal strategy to isolate MSCs from human bone marrow samples that are poorly aspirated and clotted.
基金Project supported by the National Key Research and Development Program of China(Grant No.2018YFB2200202)the National Natural Science Foundation of China(Grant No.61804148)
文摘An explanation of optical unitary transformation is presented for general nonoverlapping-image multimode interference(MMI)couplers with any number of input and output ports.The light transformation in the MMI coupler can be considered as an optical field matrix acting on an input light column vector.We investigate the general phase principle of output light image.The complete proof of nonoverlapping-image MMI coupler’s optical unitarity along with the phase analysis of matrix element is provided.Based on a two-dimensional finite-difference time-domain(2 D-FDTD)simulation,the unitary transformation is obtained for a 4×4 nonoverlapping-image MMI coupler within a deviation of 4×10-2 for orthogonal invariance and 8×10-2 for transvection invariance in the C-band spectral range.A compact 1×4 splitter based on cascaded MMI coupler is proposed,showing a phase deviation less than 5.4°while maintaining a low-loss performance in C-band spectra.
文摘Objective: To evaluate the assessment of intracranial hypertension and nerve injury in patients with hypertensive cerebral hemorrhage by transcranial Doppler (TCD). Methods: The patients who were hospitalized for hypertensive cerebral hemorrhage between August 2014 and February 2017 were selected as the cerebral hemorrhage group and healthy subjects who received physical examination during the same period were selected as the control group;TCD was used to determine the PI of affected-side and unaffected-side middle cerebral artery in cerebral hemorrhage group and lumbar puncture was done to measure intracranial pressure. The serum was collected from the two groups to detect the levels of inflammatory cytokines and nerve injury markers. Results: PI level in affected-side middle cerebral artery of cerebral hemorrhage group was significantly higher than that in the unaffected-side and positively correlated with intracranial pressure level;serum IL-1β, TNF-α, ICAM-1, MMP9, YKL-40, Asp, Glu, NPY, NSE and GFAP levels of cerebral hemorrhage group were significantly higher than those of control group, and serum IL-1β, TNF-α, ICAM-1, MMP9, YKL-40, Asp, Glu, NPY, NSE and GFAP levels of cerebral hemorrhage group of patients with high PI level were significantly higher than those of cerebral hemorrhage group of patients with low PI level. Conclusion: TCD parameters can evaluate the degree of intracranial pressure increase and nerve injury in patients with hypertensive cerebral hemorrhage.
文摘Background: The radiochemotherapy regimen concomitantly employing temozolomide (TMZ) chemotherapy and radiotherapy (RT) 4 weeks after surgery, followed by 6 cycles of TMZ is a common treatment for glioblastoma (GBM). However, its median overall survival (OS) is only 14.6 months. This study was to explore the effectiveness and safety of early TMZ chemotherapy between surgery and chemoradiotherapy plus the standard concomitant radiochemotherapy regimen. Methods: A randomized, parallel group, open-label study of 99 newly diagnosed GBM patients was conducted at 10 independent Chinese neurosurgical departments from June 2008 to June 2012. Patients were treated with concomitant radiochemotherapy regimen plus early postsurgical temozolomide (early TMZ group) or standard concomitant radiochemotherapy regimen (control group). Overall response was assessed based on objective tumor assessments, administration ofcorticosteroid and neurological status test. Hematological, biochemical, laboratory, adverse event (AE), and neurological condition were measured for 24 months of tbllow-up. The primary efficacy endpoint of this study was overall survival (OS). The secondary endpoint was progression free survival (PFS). Results: The median OS time in the early TMZ group was 17.6 months, compared with 13.2 months in the control group (log-rank test P 0.021 ). In addition, the OS rate in the early TMZ group was higher at 6, 12, and 18 months than in the control group, respectively (P 〈 0.05). The median PFS time was 8.7 months in the early TMZ group and 10.4 months in the control group (log-rank test P = 0.695). AEs occurred in 29 (55.8%) and 31(73.8%) patients respectively in early and control groups, including nausea (15.4% vs. 33.3%), vomiting (7.7% vs. 28.6%), fever (7.7% vs. 11.9%), and headache (3.8% vs. 23.8%). Only 30.8% and 33.3% were drug-related, respectively. Conclusions: Addition of TMZ chemotherapy in the early break of the standard concomitant radiochemotherapy regimen was well tolerated and significantly improved the OS of the GBM patients, compared with standard concomitant radiochemotherapy regimen. However, a larger randomized trial is warranted to verify these results.
基金Project supported by the National Natural Science Foundation of China (No. 20677030)the Development Plan of Key National Fun-damental Research (No. 2011CB503801)the Special Research Funds for Science Development in Jinan (No. 200904015), China
文摘SO2, NO2, and PM10 are the major outdoor air pollutants in China, and most of the cities in China have regulatory monitoring sites for these three air pollutants. In this study, we developed a land use regression (LUR) model using regulatory monitoring data to predict the spatial distribution of air pollutant concentrations in Jinan, China. Traffic, land use and census data, and meteorological and physical conditions were included as candidate independent variables, and were tabulated for buffers of varying radii. SO2, NO2, and PM10 concentrations were most highly correlated with the area of industrial land within a buffer of 0.5 km (R2=0.34), the distance from an expressway (R2=0.45), and the area of residential land within a buffer of 1.5 km (R2=0.25), respectively. Three multiple linear regression (MLR) equations were established based on the most significant variables (p<0.05) for SO2, NO2, and PM10, and R2 values obtained were 0.617, 0.640, and 0.600, respectively. An LUR model can be applied to an area with complex terrain. The buffer radii of independent variables for SO2, NO2, and PM10 were chosen to be 0.5, 2, and 1.5 km, respectively based on univariate models. Intercepts of MLR equations can reflect the background concentrations in a certain area, but in this study the intercept values seemed to be higher than background concentrations. Most of the cities in China have a network of regulatory monitoring sites. However, the number of sites has been limited by the level of financial support available. The results of this study could be helpful in promoting the application of LUR models for monitoring pollutants in Chinese cities.