后路减压RF-Ⅱ复位内固定椎间植骨融合术治疗腰椎滑脱症47例

目的:探讨后路减压脊柱复位固定系统(Reduction Fixation Spinal SystemⅡ,RF-Ⅱ)复位内固定椎间植骨融合术治疗腰椎滑脱症的临床疗效。方法:对应用后路减压RF-Ⅱ复位内固定并椎间植骨融合术治疗的47例腰椎滑脱症患者的临床资料,进行回顾性分析。结果:47例中滑脱椎体完全复位41例,部分复位6例,滑脱完全复位率为87.23%。按临床疗效综合评价标准:优39例,良5例,可3例,优良率93.61%;所有患者随访12～48个月,平均(21.62±0.78)个月,45例椎间植骨融合良好,2例未融合,融合率95.74%。结论:后路减压RF-Ⅱ复位内固定椎间植骨融合术治疗腰椎滑脱症复位良好,固定牢固,疗效确切,尤其适用于轻、中度腰椎滑脱症。

填充床生物膜反应器动力学模型

提出两种填充床生物膜反应器动力学模型，模型Ⅰ假设生物膜的厚度受膜内底物浓度所限制；模型Ⅱ假设生物膜厚度为常数，膜中的扩散忽略不计。两种模型正合微分方程的解析解与数值解表示出十分的吻合。

事业单位固定资产保值增值管理研究

长期以来,我国行政事业单位固定资产在保证行政事业单位正常运转。促进我国经济发展和社会进步方面发挥了重要的作用,但是在社会主义市场经济改革的高速进程中,行政事业单位的固定资产管理出现了很多问题,使得固定资产利用率低下甚至流失。对存在的问题进行了全面的思考和分析,并提出了若干改进建议。

FAULT LOCATION ESTIMATION FOR TWO-LINE FAULT INVOLVING DIFFERENT PHASES FROM EACH OF PARALLEL LINES

A novel numerical algorithm of fault location estimation for double line to ground fault involving different phases from each of two parallel lines is presented in this paper.It is based on the one terminal voltage and current data.The loop and nodal equations comparing faulted phase with non faulted phase of two parallel lines are introduced in the fault location estimation models,in which the source impedance of a remote end is not involved.The effects of load flow and fault resistance on the accuracy of fault location are effectively eliminated,therefore precise algorithms of locating fault are derived.The algorithm is demonstrated by digital computer simulations.

The internal COF features in Dome A of Antarctica revealed by multi-polarization-plane RES

The ice exceeding one million years old has significant meaning for verifying and interpreting the middle Pleistocene transition （MPT） and the relationship between greenhouse gas and climate change. The region near Dome A in Antarctica satisfies the conditions for obtaining million-years-old ice since it has low temperatures and low accumulation rates. We analyze the corresponding relation between radar wave features and the crystal orientation fabric （COF） types based on the results of multi-polarization plane radio echo sounding （RES）. The results show that, even in the summit of the ice sheet, the COF type is not perfect, but is an elongated single-pole COF. Principal-axis-orientation differences of the COF among the different periods exist and reveal that the ice flow orientations are not constant but deviate clockwise with the increasing depth. This may be related to the adjacent basal valley or both height and position changes of the summit during the glacial-interglacial periods.

Performance of bottleneck shifting for remanufacturing system considering returns' quality grading

Aimed at the remanufacturing system, the effect of the uncertainty of returns＇ quality on bottleneck shifting is investigated. A novel definition of bottleneck station is presented and the probability of a station becoming a bottleneck is also given. By calculating the effective output, the effective operation time （EOT） and the ratio of EOT of each station, the system＇s current bottleneck of effective output time is determined. By calculating the probability coefficient of variation and index of bottleneck shifting, the quantitative performance of bottleneck shifting is obtained. Discrete event simulation and the experiment design method are adopted to simulate the system, in which the proportion of quality grading, repair rates and process routes are considered. The case study shows that the uncertainty of returns＇ quality greatly increases the probability of bottleneck shifting, and with the increase of the discrete degree of the returns＇ repair rate, the bottleneck shifting phenomenon is more obvious. Furthermore, bottleneck shifting is closely related to the process route of the dominating returns＇ quality grade.

Enterolactone modulates the ERK/NF-κB/Snail signaling pathway in triple-negative breast cancer cell line MDA-MB-231 to revert the TGF-β-induced epithelial–mesenchymal transition

Objective:Triple-negative breast cancer(TNBC)is highly metastatic,and there is an urgent unmet need to develop novel therapeutic strategies leading to the new drug discoveries against metastasis.The transforming growth factor-β(TGF-β)is known to promote the invasive and migratory potential of breast cancer cells through induction of epithelial–mesenchymal transition(EMT)via the ERK/NF-κB/Snail signaling pathway,leading to breast cancer metastasis.Targeting this pathway to revert the EMT would be an attractive,novel therapeutic strategy to halt breast cancer metastasis.Methods:Effects of enterolactone(EL)on the cell cycle and apoptosis were investigated using flow cytometry and a cleaved caspase-3 enzyme-linked immunosorbent assay(ELISA),respectively.Effects of TGF-βinduction and EL treatment on the functional malignancy of MDA-MB-231 breast cancer cells were investigated using migration and chemo-invasion assays.The effects of EL on EMT markers and the ERK/NF-κB/Snail signaling pathway after TGF-βinduction were studied using confocal microscopy,quantitative reverse transcription polymerase chain reaction(q RT-PCR),Western blot,and flow cytometry.Results:Herein,we report that EL exhibits a significant antimetastatic effect on MDA-MB-231 cells by almost reverting the TGF-β-induced EMT in vitro.EL downregulates the mesenchymal markers N-cadherin and vimentin,and upregulates the epithelial markers E-cadherin and occludin.It represses actin stress fiber formation via inhibition of mitogen-activated protein kinase p-38(MAPK-p38)and cluster of differentiation 44(CD44).EL also suppresses ERK-1/2,NF-κB,and Snail at the m RNA and protein levels.Conclusions:Briefly,EL was found to inhibit TGF-β-induced EMT by blocking the ERK/NF-κB/Snail signaling pathway,which is a promising target for breast cancer metastasis therapy.

STUDY OF NON-CONTACT MEASUREMENT OF FREE-FORM SURFACES

A non contact three dimensional measurement method is presented in this paper.This system consists of a laser triangulation probe,a probe head and a coordinate measuring machine (CMM).The measurement principle of the system is discussed,and a system calibration method employing a reference ball is proposed.The geometric model involving four frames is established to calculate the data points based on the reading of the laser probe and position information from the CMM.A measuring experiment for gesso free form surface using this system is carried out.

Altered spontaneous contractions of the ileum by anesthetic agents in rats exposed to peritonitis

AIM： To investigate in vitro effects of propofol, midazolam and dexmedetomidine, which are commonly used anaesthesic or sedatives, on spontaneous contractions of the ileum both in normal rats and those exposed to hyperdynamic peritonitis.METHODS： Spontaneous contractions of isolated ileum muscle segments from sham operated rats and those exposed to peritonitis, were studied in vitro. The amplitude and the frequency of spontaneous contractions of ileum muscle segments were studied after adding dexmetetomidine, propofoi, and midazolam to the organ bath in a cumulative manner.RESULTS： Both amplitude （85.2 ± 6.6 vs 47.4 ± 7.1） and frequency （32.8 ± 4.6 vs 20.2 ± 3.9） of spontaneous contractions in ileum smooth muscle segments were decreased significantly in the peritonitis group compared to the control group （P 〈 0.05）. Dexmedetomidine significantly increased the amplitude of spontaneous contractions （85.2 ± 6.6 vs 152.0 ± 5.4, P 〈 0.05） whereas, propofol （85.2 ± 6.6 vs 49.6 ± 4.8, P 〈 0.05） and midazolam （85.2 ± 6.6 vs 39.2 ± 4.5, P 〈 0.05） decreased it in both control and peritonitis groups. The frequency of spontaneous contractions were significantly decreased by propofol in both control （32.8 ± 4.6 vs 18.2 ± 3.4, P 〈 0.05） and peritonitis groups 20.2 ± 3.9 vs 11.6 ± 3.2, P 〈 0.05）. Dexmedetomidine and midazolam did not cause significant changes in the number of spontaneous contractions in both control and the peritonitis groups （P 〉 0.05）.CONCLUSION： Propofol, midazolam and dexmede- tomidine have various in vitro effects on spontaneous contractions of the rat ileum. While dexmedetomidine augments the spontaneous contraction of the rat ileum, propofol attenuates it. However, the effects of these compounds were parallel in both control and peritonitis groups.

Dating of the topmost terrace in the Jingxian Basin,Anhui Province:an indication of the establishment of the Qingyijiang River

On the northern fringe of Mt. Huangshan, many fiver terraces are developed at the junction between mountains and plains. The fiver terraces are most typical in the Jingxian Basin, Anhui Province, where the Qingyijiang River, one of the longest tributaries of the lower Yangtze River, developed three staircase terraces. The topmost terrace （i.e., the T3 terrace） tread is 38 - 39 m above fiver level, and the top of the gravels is generally covered by 3 - 10.9 m of red clay deposits. Systematic magnetostratigraphy and electron spin resonance dating are used to research the timing of the establishment of the Qingyijiang River. The main results show that the topmost terrace developed no later than 900 kyr ago and that the appearance of the Qingyijiang River occurred correspondingly at least before 900 kyr ago on the northern fringe of Mt. Huangshan. In view of the almost synchronous age,the establishment of the Qingyijiang River was seemingly a response to the Mid-Pleistocene Revolution when the 100 kyr cycle commenced, and the Kunlun-Huanghe movement during the early- middle Pleistocene transition. In addition, the establishment of the Qingyijiang River possibly reflected the birth of the modem Yangtze River to some degree. Therefore the timing of the formation of the Yangtze River is restricted to no later than 900 kyr ago based on the appearance of the Qingyijiang River .

Determination of Causal Effect in Observational Studies： Analysis of Correlated Data with Binary End-Points

Identifying the causal impact of＇ some intervention challenging when one is faced with correlated binary end-points in observational studies is a challenging task, and it is even more The statistical literature on analyzing such data is well documented. Dependence between observations from the same study subject in correlated data renders invalid the usual chi-square tests of independence and inflates the variance ofparameter estimates. Disaggregated approaches such as hierarchical linear models which are able to adjust for individual level covariate：s are favoured in the analysis of such data, thereby gaining power over aggregated and individual-level analyses. In this article the authors, therefore, address the issue of analyzing correlated data with dichotomous end-points by using hierarchical logistic regression, a generalization of the standard logistic regression model for independent outcomes.

DVB-S2 inner receiver design for broadcasting mode

This paper details on the design of DVB-S2 receivers which is compliant with the broadcasting mode. Special at-tention is paid to the specific receiver functions necessary to demodulate the received signal. To show the system performance we consider the design of a complete receiver consisting of timing recovery unit, frame synchronization unit, frequency recovery unit and phase recovery unit. The system is easier to hardware implementation comparing with that provided in (ETSI, 2005; Sun et al., 2004). After the performance of the algorithms is analyzed and a quantitative result is given, this allows us to draw conclusions concerning the achievable system performance under realistic complexity assumptions.

An Empirical Analysis of Employment Stability and the Wage Gap of Rural Migrants in China Based on Quantile Regression

Under the background of accelerated integrated urban-rural development, this paper offers an analysis on the short-term employment of rural migrants in China and resulting wage gap between long-term and short-term rural migrants. On the basis of correcting for sample selection problems arising from labor market participation and short-term employment, rural migrants＇ wage function is estimated using quantile regression method, and wage gap between long-term and short-term rural migrants is decomposed using MM method. Our empirical results suggest that those with a higher level of education, training experience and local employment recommended by family relations or in formal labor market are more likely to secure long-term labor contract,＂ region and education have significant contributions to the wage of rural migrants,＂ rural migrants of both long- and short-term contract types have great gaps at the bottom of salary distribution; and there exists a sticky floor effect in wage difference of rural migrants. These results have important policy implications in enhancing employment stability of rural migrants, improving income distribution equity, speeding up the process of urbanization, and balancing regional development.

Convergences in the diversification of bats

Twenty-five characters or suites of characters from bats are considered in light of changes in bat classification. Thecharacters include some associated with flower-visiting (two), echolocation (12), roosting (six), reproduction (two) and three areof unknown adaptive function. In both the 1998 and 2006 classifications of bats into suborders (Megachiroptera and Microchiropteraversus Yinpterochiroptera and Yangochiroptera, respectively), some convergences between suborders are the same (e.g.,foliage roosting, tent building), but others associated with echolocation differ substantially. In the 1998 phylogeny convergencesassociated with echolocation (high duty cycle echolocation, nasal emission of echolocation calls) occurred among the Microchiroptera.In the 2006 phylogeny, they occur between Yinpterochiroptera and Yangochiroptera. While some traits apparently aroseindependently in two suborders (e.g., foliage-roosting, tent building, low intensity echolocation calls, noseleafs, nasal emission ofecholocation calls, high duty cycle echolocation behaviour), others appear to have been ancestral (roosting in narrow spaces,laryngeal echolocation, stylohyal-tympanic contact, oral emission of echolocation calls, and small litter size). A narrow profilethrough the chest is typical of bats reflecting the thoracic skeleton. This feature suggests that the ancestors of bats spent the day insmall crevices. Features associated with laryngeal echolocation appear to be ancestral, suggesting that echolocation evolved earlyin bats but was subsequently lost in one yinpterochiropteran lineage .

Molecularly Imprinted Polymers for Selective Extraction of Crystal Violet from Natural Seawater coupled with HighPerformance Liquid Chromatographic Determination

Molecularly imprinted polymers （MIPs） were prepared by the bulk polymerization using crystal violet as the template molecule, and the methacrylic acid and ethylene glycol dimetheacrylate as functional monomer and cross-linker, respectively. Sys- tematic investigations of synthetic conditions were conducted. The surface morphology and recognition mechanism of the obtained polymers were studied using scanning electron microscope and spectrophotometric analysis. MIPs showed high atTmity to template molecule and were successfully applied as special solid-phase extraction sorbent for selective extraction of crystal violet from natural seawater. An off-line molecularly imprinted solid-phase extraction （MISPE） method followed by high-performance liquid chroma- tography with diodearray detection for the analysis of crystal violet was also established. MISPE columns have good recoveries for crystal violet standard solutions and good linearity was obtained over the concentration range of 0-200 ~tg L-1 （R2 〉 0.99）. Finally, two natural seawater samples were investigated. The recoveries of spiked seawater on the MISPE columns were from 44.47% to 62.34%, the relative standard deviation （n=3） being in the range of 2.89%-5.96%.

Component Analysis of Volatile Oil of Garlic from Different Districts and Assay of Allicin Content

[ Objective] The aim was to study the chemical component of volatile oil of garlic in different districts. [ Method] GC-MS was used to an- alyze the composition of the garlic volatile oil in Guiyang, Guizhou Majiang, Shandong, Yunnan and Chongqing and the HPLC method was used to assay the content of gadicin. [ Result]Gadicin in different essential oil had the highest content but varied a lot. The sampling amount of garlicin be- tween 0.562 and 2.810 μg was in a good linear relation （R =0.999 2, n = 5 ） with peak area, the average recovery rate was 99.39, RSD = 1.76%. [ Conclusion] GC-MS can be used to analysis the composition of essential oil quickly and effectively. The liquid chromatographic analysis of garlicin was simple, reliable and reproducible. The study provided the theoretical basis for selecting garlic in gadic flavor oil production and improving quality of gadicin oil.

Stability and structural dimension of access mechanized panel

To acquire a knowledge of the stress-strain state in the process of mining beforehand, a numerical method was used to simulate the stoping process of access mechanized panel mining in No. 3 ore-body of Tonglushan mine; and for the sake of obtaining better stability, the optimal panel dimension and access stoping sequence were researched. The results show that the integral stability of the mechanized panel of No. 3 ore-body is passable in the process of winning at full level height; the stability of panel tends to be worse gradually with continuous increasing of panel width; and the better width of access panel in No.3 ore-body is less than 52 m. It is indicated that 3D elasto-plastic finite element method can make a satisfactory study of numerical simulation on the panel stability and its structural dimension in the test for the upward access mechanized-panel mining. The results of the theoretical calculation and analysis accord with the actual situation from the field ground pressure monitoring.

A nonlinear rheological model of backfill material for retaining roadways and the analysis of its stability

The long-term stability of backfill material is the key to retaining roadways successfully. In order to study the rheological deformation of backfill material and its long-term stability, given the visco-elastoplastic properties of this material, we introduced a softening and a hardening function for a new nonlinear the- ological model with time-varying parameters. Based on this, we presented the instability condition of this model by using the principle of minimum potential energy. Combined with engineering practice, we cal- culated the urlstable time period of backfill material. The results show that the time of instability of the backfill material relate to the initial parameters of the material, ＂the coefficients decided by temperature and the ratio of the plastic zone of the backfill material. Based on the results of our analysis from the point of view of energy, we can quickly obtain the time of instability of this model from our graphical analysis. The time of instability of the backfill material obtained from our investigation coincides with an actual project.

Farmers＇ Perceived Impact of Fair Trade： The Case of Costa Rica

The perceived usefulness of Fair Trade influences both its effectiveness and farmers＇ long-term participation. The aim of this paper is to measure the perceived economic, social and environmental impact of Fair Trade by farmers in Costa Rica. One hundred farmers were interviewed, and their perceived change in living and working conditions due to Fair Trade participation was measured through a t-test analysis. The sample characters＇ influence on the perceived change was also measured, adopting a regression model and a t-test. The results showed a positive perception of the impact of Fair Trade, with a particularly strong perceived improvement in the farmers＇ technical, economic and managerial skills. There was relatively less perceived change in the environmental, educational and sanitary conditions. The results showed the need for Fair Trade to better adjust its strategy to the expectations of the farmers＇ communities.