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Zero-utility principle is one of the main premium pricing principles, which has been widely used in insurance practice. In this paper, the nonparametric estimation of zero-utility premium is given. In addition, the consistency and asymptotic normality of the estimation are proved. Some special cases including linear, exponential and quadratic utility are discussed. Finally, the Monte Carlo method is used to show the convergence rate of premium estimation. Furthermore, the histogram and Normal-Probability-Plot are given to investigate the asymptotic normality of the estimators. The results show that our estimations are good enough to use in practice.

In this paper, we construct a nonparametric regression quantile estimator by using the local linear fitting for left-truncated data, and establish the Bahadur-type representation and asymptotic normality of the proposed estimator when the observations form a stationary α -mixing sequence. Finite-sample performance of the estimator is investigated via simulation studies.

A numerical model research of fine-blanking has been built up. The fine-blanking process of parts with pressure is 0KN20 KN40 KN60 KN respectively , thickness of plate 2.9mm and diameter 16mm,of steel 45, has been simulated. Through simulation, the study gets the material distribution situation of mean-stress fields in the progress of fine-blanking, and analyzes the relation between mean-stress fields and the crack of shearing zone. And get the pressure optimization value.

In this paper, we construct a local linear composite quantile regression (CQR) estimator of regression function for left-truncated data, which extends the CQR method to the left-truncated model. The asymptotic normality of the proposed estimator is also established. The estimator is much more efficient than the local linear regression estimator for commonly-used non-normal error distributions via simulations.

a numerical model research of fine-blanking has been built up. The fine-blanking process of parts with clearance 0.1%S, 0.7%S, and 1.3%S. (S stands for the thickness of the material) respectively, thickness of plate 2.9mm and diameter 16mm of steel 45, has been simulated. Through simulation, the study gets the material distribution situation of mean-stress fields in the progress of fine-blanking, and the author analyzes the relation between mean-stress fields and the crack of shearing zone. Through analysis the author concluded that the section quality grows with decrease of blanking clearance.

RT（X-Radiography Testing） is a very import inspection method for detecting engine blade crack, and the defect is identified by person distinguishing the film for traditional RT. The traditional method is involved in high mistake and missed examining rate and low efficiency. It is great significance to blade integrity and flight safety that the crack can be quickly distinguished. In the paper, adopting a adaptive segmenting algorithm based on OTSU to quickly distinguish the crack on the blade image, and it can definite the threshold facing different gray image, and can reliably inspect the cracks which detection rate was 98%. The recognition accuracy for crack can reach 0.16mm Simulation result verify that the method is very effective on adaptively segmenting the blade image according to the threshold for crack inspection

The positioning accuracy can bring a great impact on inspecting defect for Aero-engine blade. The high or low pressure rotor of engine is generally driven by manual when blade’s defect is inspected. Frequently，False detection and missed happens due to match failure between two persons. Adopting a high-resolution, high-accuracy algorithm based on FPGA to design automotive equipment for high or low rotor . The Frequency range to step motor is 1Hz / s to 65536Hz / s, resolution is 1Hz,and positioning accuracy for blade can be up to 1mm.Resolving the questions of missing detectable rates made by manual during inspection in the paper, and increasing efficiency for inspection and the reliability of the experimental result. Experiment results show that this equipment can meet the challenge of the high-accuracy regulating speed for blade’s inspection.

Carbon dioxide (CO2) gas sensor using surface acoustic wave (SAW) device based on Zinc oxide (ZnO) was developed and fabricated in this paper. The center frequency of SAW device is 203.528 MHz. The input and two output interdigital transducers (IDT) apodized by Morlet wavelet function can improve the side lobe rejection compared with uniform IDT. The ZnO film sensitive to CO2 gas was fabricated in measurement acoustic track of SAW device. Experiments results confirm that the CO2 gas sensor using SAW device based on ZnO film has good response characteristics to different concentrations CO2 gas. Furthermore, the CO2 gas sensor using SAW device based on ZnO film has good stability and linearity.

In the design process of surface acoustic wave (SAW) device based on multistrip coupler (MSC), the characteristics of interdigital transducer (IDT) and device can not been directly achieved, and the layout structure of device can not be observed and checked. To solve some problems, the design platform of SAW device based MSC was realized in the Matlab design environment using the modular design. The design platform of SAW device based MSC consists of layout simulation module, characteristics simulation module and data output module. By means of realizing a SAW device based MSC with center frequency at 51.293MHz, the comparison and analysis between the design results and the actual test results are presented. Experiments results confirm that the platform can correctly design the device layout. The device characteristics achieved by the design platform are in good agreement with the actual measurement results by the network analyzer.

FreeCutting Austenite Stainless Steel 303CuS2(%:≤0.08C,8.00~10.00Ni, 17.00~19.00Cr, 1.50~3.50Cu,0.24~0.35S) is smelted by 60t Electric Arc Furnace~60t Argon Oxygen Decarburization~60t Ladle Furnace~3 Flow continuous casting machine. With decreasing basicity of AOD refining slag from 2.0 to 1.6, controlling AOD tapping slag amount and tapping temperature, the [S] in AOD tapping steel increases to 0.008%~0.012% from original 0.004%~0.006%, after feeding S-wire containing 50% S and controlling the end temperature, the yield of S increases to 60%~70% from original 30%~50%, the qualified ratio of raises from 85% to 100%.

Developed by the Virginia Bioinformatics Consortium (VBC), GeneX Va is an open source, freeware database and bioinformatics analysis software for archiving and analyzing Affymetrix GeneChip®data. It provides an integrated framework for management, documentation, and analysis of microarray experiments and data to support a range of users, from individual research laboratories to institutional microarray facilities. GeneX Va also provides web-based access to a PostgreSQL relational database system with a comprehensive security system. Data can be extracted from the database and delivered to interactive or scriptable statistical analysis protocols. The security system allows each investigator to manage their own array data and analysis output files and also provides custom access privileges for other users, groups, and internal/external collaborators. The analysis interface uses “Analysis Trees,” an innovative user interface that allows researchers to interactively create a tree-structured flow chart of analysis routines. The latest GeneX Va software is available from and can be freely downloaded at the Sourceforge web site http://va-genex.sourceforge.net . To allow researchers to access the database and analysis capabilities of the GeneX Va system, microarray data from many VBC GeneChip experiments have been deposited into a public section of the GeneX Va system at the University of Virginia. The VBC GeneX Va sites, which include documentation, are at http://genes.med.virginia.edu/ of the University of Virginia and at http://genex.csbc.vcu.edu/ of the Virginia Commonwealth University.

In trypanosomatids, the spliced leader RNA, or SL RNA, donates its 5′ 39 nucleotides to mature nuclear mRNAs in a process termed trans-splicing. We have previously characterized the SL RNA gene from Trypanosoma cruzi and identified its transcription promoter, including a 14 nt proximal sequence element, or PSE, that binds a putative transcription factor and activates transcription of the gene. Herein, we describe establishment of a yeast one-hybrid system using the 14 nt PSE as bait, and use this system to select T. cruzi cDNAs encoding a putative transcription factor that activates transcription of the SL RNA gene. The cDNA was selected from a normalized library and encodes an ∼45 kDa putative PSE promoter-binding protein, PPB1. PPB1 in vitro translated or overexpressed in and isolated from transformed E. coli , showed PSE-specific binding activity by electrophoretic mobility shift assays. Finally, overexpression of PPB1 in T. cruzi led to increased expression of the SL RNA gene as well as reporter genes in episomal constructs under the control of the SL RNA gene promoter. These observations suggest that PPB1 is a transcription factor that plays an important role in SL RNA gene expression.

ObjectiveA simple FFQ which ranks young children's dietary habits is necessary for population-based monitoring and intervention programmes. The aim of the present study was to determine the reliability and validity of a short FFQ to assess the dietary habits of young children aged 2–5 years.DesignParents completed a seventeen-item FFQ for their children by telephone on two occasions, two weeks apart. Sixty-four parents also completed 3 d food records for their children. The FFQ included daily servings of fruit and vegetables, frequency of eating lean meat, processed meats, take-away food, snack foods (biscuits, cakes, doughnuts, muesli bars), potato crisps and confectionery, and cups of soft drinks/cordials, juice, milk and water. Weighted kappa and intra-class correlation coefficients were used to assess FFQ reliability and the Bland–Altman method was used to assess validity of the FFQ compared with the 3 d food record.SettingSeven pre-school centres in metropolitan Sydney, Australia.SubjectsSeventy-seven children aged 2–5 years.ResultsThe majority of questions had moderate to good reliability: κw ranged from 0·37 (lean meat) to 0·85 (take-away food consumption). Validity analysis showed a significant increase in mean values from the food record with increasing ordered categories from the FFQ for servings of vegetables and fruit and cups of drinks (all trend P ≤ 0·01). Spearman rank correlation coefficient was >0·5 for vegetables, fruit, diet soft drinks and fruit juice.ConclusionsThe FFQ provides reliable and moderately valid information about the dietary intakes and habits of children aged 2–5 years, in particular for fruit, vegetables and beverages.

The study was to investigate the role of homocysteine (Hcy) which was released by hippocampal glial cells and its relationship with NMDA receptor and AMPA receptor in depression induced by chronic unpredictable mild stress (CUMS), and explore the mechanism of changes of Glu/Glu receptor in glial cells and neurons. CUMS-induced depression model was established. The body weight of rats was weighed on the 1st, 7th, 14th, and 21st days during the experiment. The behavioral performances were observed by means of sucrose consumption test, open field test and tail suspension test. Intrahippocampal microinjection of Hcy, NMDA receptor antagonist MK-801 and AMPA receptor antagonist NBQX was performed under stereotaxic guide cannula. The concentration of Glu and the expression of its receptors' subunits were detected respectively by high performance liquid chromatography (HPLC) and Western blot. The Hcy content and the levels of phosphorylation of NMDA receptor and AMPA receptor in hippocampus were separately determined by enzyme linked immunosorbent assay (ELISA). The results showed that CUMS significantly induced the depression-like behaviors in rats, and the content of Glu and Hcy, the expression of NMDA receptors' subunits NR1/NR2B and the level of phosphorylation of NMDA receptor (p-NMDAR) in hippocampus increased significantly, while the expression of AMPA receptors' subunits GluR2/3 and the level of phosphorylation of AMPA receptor (p-AMPAR) decreased significantly. Microinjection of Hcy into hippocampus resulted in similar animal depression-like behaviors and increased Glu content compared to the CON/SAL group, the expression of NR1/NR2B/GluR2/3 and the level of p-NMDAR increased significantly, but the level of p-AMPAR reduced observably. Intrahippocampal injections of MK-801 effectively improved the depression-like behaviors induced by CUMS and Hcy, and attenuated the elevation of Glu content induced by Hcy in hippocampus, whereas NBQX could not improve the depression-like behaviors, but also decreased the Glu content induced by Hcy remarkably. These results suggest that CUMS may contribute to the production and release of Hcy via hippocampal astrocytes. Through the increase of expression of NR1/NR2B/GluR2/3 and level of p-NMDAR, and the decrease of level of p-AMPAR, Hcy results in elevation of Glu level, which leads to depression-like behaviors in the end. In a word, the Hcy released by astrocytes plays an important role in stress-induced elevation of Glu content and variation of NMDA/AMPA receptors in hippocampus.

BACKGROUND: NT-proBNP has been widely regarded as a useful tool for diagnosis or exclusion of heart failure (HF) in many settings. However, in patients with acute exacerbation of chronic bronchitis (AECB), its roles have not been well described. The objective of this study was to evaluate the diagnostic performance of NT-proBNP for identifying left ventricular (LV) failure in such patients. METHODS AND RESULTS: 311 AECB patients and 102 stable chronic bronchitis patients with no history of HF were enrolled. Plasma NT-proBNP concentrations were measured using Roche Elecsys. The European Society of Cardiology (ESC) diagnostic principles were adopted to identify HF and the diagnostic performance of NT-proBNP was evaluated by ROC. Our results showed, the median NT-proBNP level in patients with LV failure [4828.4 (2044.4-9203.6) ng/L] was significantly higher than that in those without LV failure [519.2 (179.1-1409.8) ng/L, p

To observe the expression of R. gracilis D-amino acid oxidase (DAAO) gene labeled by EGFP in HeLa cells and how it mediates cytotoxicity, DAAO cDNA and EGFP gene were cloned into Eukaryotic expression vector pIRES to construct DAAO gene expression vector pIRES-DAAO. HeLa cells were transfected with pIRES-DAAO in vitro. Expression of EGFP gene in HeLa-D cells was observed under a fluorescent microscope. The efficiency of transfection was analyzed by flow cytometry (FCM). The fluorescent cells were screened by FCM and were named HeLa-D. The activity of HeLa-D cells was detected by MTT colorimetric assay after they were treated with D-Ala at various concentrations. The results indicted that expression of EGFP gene in HeLa-D cells was seen under fluorescent microscope and HeLa-D cells were screened by FCM. Apparently,the prodrug D-Ala killed HeLa-D cells. These results demonstrate that EGFP gene can be regarded as a reporter gene to screen the cells transduced with DAAO quickly, and DAAO/D-Ala suicide gene system may prove helpful in gene therapy of cancer.

To compare large-scale real-time titration method (LaSRT) with standard titration method by flow cytometry (FACS) for determining the titers of green-fluorescence-protein (GFP)-marked recombinant retrovirus.(1) Standard titration method: NIH3T3 cells were inoculated at 2x10(5) /well in 6-well plate, and after cell culture for 12 h, 0.5 ml, 50 microl and 5 microl GFP-marked recombinant retrovirus (n=3) were respectively used to infect the cells, with the final concentration of polybrene being 8 microg/ml. Forty-eight hours later, the cells were treated with trypsin and assayed for the positive rate of GFP by means of FACS. When the positive rate was lower than 10%, the titer was calculated according to the equation: virus titer (TU/ml) =2x10(5)xGFP positive rate/volume of virus stock solution used. (2) LaSRT method: The cells were inoculated at 5,000 cells/well in a 96-well plate, and after cell culture for 12 h, 90 microl/well complete culture medium was used with 8 microg/ml polybrene and 10% newborn bovine serum, 10 microl virus was added into the first well, and ten-fold dilution of the previous virus-containing solution was performed before the virus was added into the next well (8 wells in each group, altogether 3 groups). Forty-eight hours later, inverted fluorescence microscope was used to observe the fluorescence-positive cells in each well. The virus titer was calculated according to the equation: virus titer (TU/ml) =mx10(n+1), where n is the serial number of the reference well, and m the number of positive cells. (3) LaSRT was used to study the influence of freezing/thawing on the titers of recombinant retroviruses.The virus titer obtained with standard method by FACS was (1.54+/-0.38)x10(6) TU/ml, and that of LaSRT was (1.33+/-0.57)x10(6) TU/ml (P0.05). After one cycle of freezing/thawing, the virus titer dropped to (18.1+/-9.9)% (n=7).LaSRT is more rapid and convenient as well as easier to determine the virus titer compared with standard method, and no significant difference is found between the two titration methods.

Wen, L.-M., Xu, P., Benegal, G., Carvaho, M. R. C., Butler, D. R., and Buck, G. A. 2001. Trypanosoma cruzi: Exogenously regulated gene expression. Experimental Parasitology97, 196–204. A regulated expression vector would provide a strong tool for the dissection of gene function in Trypanosoma cruzi. Herein, we establish a system in which genes in T. cruzi expression vectors can be exogenously regulated by tetracycline. We first generated strains of T. cruzi that stably express the repressor of the bacterial tetracycline resistance gene and T7 RNA polymerase. Based on these strains, we developed two T. cruzi expression systems regulated by tetracycline—the first by use of a regulated rRNA promoter and the second by use of a regulated T7 promoter. In the former, we constructed an expression vector in which tetracycline resistance gene operators flank the transcription start point of the T. cruzi rRNA gene promoter. Reporter gene activity from this modified promoter was regulated up to 20-fold in the presence of different concentrations of tetracycline. In the T7 system, tetracycline resistance gene operators flank the transcription start point of the T7 promoter. Reporter gene activity from this modified promoter was regulated up to 150-fold in the presence of different concentrations of tetracycline. Expression in these systems was repressed when tetracycline was removed even after full induction for extended periods in the presence of tetracycline. We are now using these two systems to test protein function in T. cruzi.

Nuclear mRNAs in trypanosomatids are generated by trans-splicing. Although trans-splicing resembles cis-splicing in many ways and most of the U RNA participants have been characterized, relatively few involved proteins have been identified. Herein, we employed a yeast three-hybrid system to identify a protein, XB1, which binds to the Trypanosoma cruzi SL RNA. XB1 is a 45 kDa protein which is homologous to the essential pre-mRNA-splicing factor PRP31p from Saccharomyces cere6isiae .G el shift assays and UV cross-linking experiments with recombinant XB1 confirmed that this T. cruzi protein binds the SL RNA in vitro. The binding site of XB1 on the SL RNA was mapped to stem-loop II by deletion of the SL RNA ‘bait’ in the three-hybrid system. Finally, UV cross-linking SL RNA with S100 extract indicated native XB1 protein and SL RNA interaction in T. cruzi extract. © 2001 Elsevier Science B.V. All rights reserved.