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Pretreatment methods play an important role in the improvement of biogas production from the anaerobic digestion of energy grass. In this study, conventional thermal and microwave methods were performed on raw material, namely, Pennisetum hybrid, to analyze the effect of pretreatment on anaerobic digestion by the calculation of performance parameters using Logistic function, modified Gompertz equation, and transference function. Results indicated that thermal pretreatment improved the biogas production of Pennisetum hybrid, whereas microwave method had an adverse effect on the performance. All the models fit the experimental data with R (2) 0.980, and the Reaction Curve presented the best agreement in the fitting process. Conventional thermal pretreatment showed an increasing effect on maximum production rate and total methane produced, with an improvement of around 7% and 8%, respectively. With regard to microwave pretreatment, maximum production rate and total methane produced decreased by 18% and 12%, respectively.

The effects of CuO additive on sintering temperature and microwave dielectric properties of 7NiNb2O6–9TiO2 ceramics prepared by solid-state reaction method have been investigated. The phases and microstructure have also been evaluated using X-ray diffraction and scanning electron microscopy. The pure 7NiNb2O6–9TiO2 ceramics show a high sintering temperature of about 1,200 °C. However, the addition of CuO lowered the sintering temperature of 7NiNb2O6–9TiO2 ceramics from 1,200 to 935 °C due to the CuO liquid-phase. The results showed that the microwave dielectric properties were strongly dependent on densification, crystalline phases and grain size. The 7NiNb2O6–9TiO2 ceramics with the addition of 3.2 wt% CuO sintered at 935 °C afforded excellent dielectric properties of e r = 60.5, Q × f = 10,039 GHz (at 3.8 GHz) and τ f = 62 ppm/°C, which represented very promising candidates for LTCC dielectric materials.

Performance of cathode electron receivers has direct effect on the voltage and power density of MFC. This paper explored the electrical performance of MFC with potassium permanganate, ferricyanide solution and dissolved oxygen (DO) as cathode electron receivers. The results showed that the internal resistance of MFC with DO depends on catalyst and is higher than that of MFC with potassium permanganate and potassium ferricyanide solution. The maximum volume power density is 4.35 W/m3, and the smallest internal resistance is only about 54 Ω. In case of DO, the internal resistance and power density is different depending on the catalyst and is not too much related to the membranes.

補光区, 遮光区および対照区の3実験区を設定してミニチュアローズRosa‘Fiesta Parade (POUlesta)’を秋, 春, 夏に栽培した. 秋栽培の補光区の草丈および生茎重は対照区を有意に上回った. 遮光区の葉面積, 葉数, 草丈, 生茎重は秋栽培において著しく抑制され, 対照区との間に有意な差が認められた. しかし, これらの遮光区と対照区との差は春栽培や夏栽培では小さくなった. 花蕾シュート数は夏栽培で最も多く, 春栽培, 秋栽培の順となり, いずれの栽培期間でも遮光区で有意に少なかった. 対照区における積算日射量, 積算昼間気温および積算夜間気温を説明変数として算出した葉面積, 生葉重, 生体重, 葉数および草丈の重回帰式は0.9以上の重相関係数を示し有意であった. 対照区で求めた重回帰式を用いて推定した補光区と遮光区の成育推定値と実測値との間には有意な正の相関が認められ, 各関係式の傾きは補光区で0.921～0.948,遮光区で0.930～1.013であった. したがって, 対照区で算出した重回帰式を用いて, 補光や遮光, 加温などの日射量や温度制御を行った場合の成育予測が可能であった.

In this study, a pilot scale of 100 t/year biodiesel production system, mainly consisting of a fixed-bed and a down-stream plug-flow reactors, was setup to test different feedstock oils, especially a kind of high-acidified oil, trap grease, for their feasibility as biodiesel feedstock in China. The tested oils include three kinds of typical oil from Guangdong Province, China: rapeseed oil, Chinese wood oil, and trap grease. At the same time the optimum residence time for a plug-now reactor to perform transesterification reaction was investigated in this study. At the temperature of 65 degrees C, methanol/oil molar ratio of 6:1 and KOH load of 1.2 wt% of oil, the optimum residence time was found to be 19 min. A type of ion-exchange resin was used to fill in the fixed-bed reactor and used as the esterification catalyst for pretreating on the high-acidified oil. For the fresh catalyst, the acid value of trap grease could be reduced from 114 mg KOH/g to about 2 mg KOH/g after 13 h at temperature 75 degrees C, catalyst load of 15 wt% of oil, methanol addition of 20 wt% of oil. The lifetime test for the catalyst indicated that its life is over 30 days. The quality of biodiesel derived from three feedstock oils is compared with newly published China BD100 standard of GB/T20828-2007. A comparison of the results reveals that the biodiesel generated through this system could satisfactorily meet China BD100 standard. It indicates that the designed process in this system has a good adaptability for different kinds of oil. (C) 2009 Elsevier Ltd. All rights reserved.

Rosa multiflora ‘Matsushima No. 3’ は Pythium helicoides によるバラ根腐病に対して抵抗性を持っているが，その抵抗性機構については明らかとなっていない．バラに対する P. helicoides の感染過程は初期感染過程と後期感染過程の2過程に分類されており，本研究では ‘Matsushima No. 3’ の抵抗性を明らかにするために罹病性のバラ品種と比較し，初期感染過程である遊走子の走化性，付着，被のう化，根の表面での菌糸の発芽に着目して調査した．生産現場において抵抗性を示した ‘Matsushima No. 3’ と罹病性の R. ‘Fashion Parade’ を供試材料として用いた．挿し木して発根させた ‘Matsushima No. 3’ と ‘Fashion Parade’ を P. helicoides の遊走子懸濁液に浸漬して接種し，接種後 7 日目に根腐症状を調査した．接種検定の結果，‘Matsushima No. 3’ はバラ根腐病に対して抵抗性があり，‘Fashion Parade’ は罹病性であることが確認できた．光学顕微鏡での観察から，P. helicoidesの 遊走子は，‘Fashion Parade’ と同様に，‘Matsushima No. 3’ の根の抽出物を含む寒天を充填した微細管の端に誘導されて凝集しており，さらに遊走子は ‘Matsushima No. 3’ の根の表面でも被のう化していた．従って，‘Matsushima No. 3’ は遊走子の走化性および被のう化を阻害していなかった．走査電子顕微鏡での観察から，‘Matsushima No. 3’ および ‘Fashion Parade’ の根の表面でほとんどの被のう胞子が発芽しており，菌糸の表皮への侵入率は ‘Matsushima No. 3’ では 55.0％，‘Fashion Parade’ では71.2％であった．感染初期過程において両品種間で差が認められなかったことから，‘Matsushima No. 3’ の抵抗性機構は初期感染過程ではなく後期感染過程で発現されており，皮層組織で菌糸が伸長するのを抑制する機構が作用すると考えられた．

エブアンドフロー方式でのミニチュアローズの鉢物生産において, 気象要因を用いて推定した総葉面積とペンマン法による蒸発散位から蒸発散量を推定した. 実測した蒸発散量と総葉面積を用いて推定した蒸発散量との関係から, 推定値が実測値より大きな値を示し, LAIを考慮した総葉面積を用いて蒸発散量を推定する必要があった. LAIを用いて修正した葉面積とペンマン法による蒸発散位から求めた蒸発散量と実測した蒸発散量との間にはY=1.07X (R2=0.75)の有意に高い相関が認められ, 気温, 湿度, 日射量を用いて30分ごとの蒸発散量をある程度推定できた. しかし, ピンチ後の10日間の生育が劣っている時期やLAI>2.8のシュートの生育が旺盛な時期では蒸発散量の推定値が実測値と大きく異なる場合が認められ, 蒸発散量推定式の精度を低下させていた. 鉢内土壌の水分量とpF値との間には有意な相関がみられ, 潅水点pF2.1の鉢内土壌水分量は93.0 ml pot-1であった. 鉢土の圃場容水量はミチュアローズの生育や栽培時期の影響を受けず210.0 ml pot-1で一定であり, 潅水点までの総蒸発散量は117.0 ml pot-1と推定できた. 本研究の結果から, ミニチュアローズの鉢物生産における蒸発散量をある程度予測できる可能性が示唆されたことから, 気温, 湿度, 日射量などの気象データに基づいた潅水点の予測が可能であるかもしれない.

In the applications based on depth, multiple TOF cameras are often required to capture the same scene. But if multiple cameras operate simultaneously on the same frequency, they interfere with each other. The multi-camera interference causes a lot of errors in depth measurement. The depth quality is severely reduced, which limits the application of TOF cameras and needs to be resolved. In this paper, a multi-camera interference model is presented. The interference signal for multiple frames is proved to be an ergodic and wide-sense stationary stochastic process. The least square estimation of noninterference signal is proposed to remove the multi-camera interference. The results of experiments prove the approach can recover the depth and amplitude information of multiple TOF cameras from the severe interference.

Often, many software systems fail to meet requirements because of a lack of performance. A proven method for preventing or for diagnosing performance problems is through modeling. Layered Queueing Networks (LQN) are one popular technique for solving performance models. However, if a LQN is solved through decomposition and Mean Value Analysis (MVA), erroneous results can arise because of traffic dependencies in the decomposed models. This paper addresses one traffic dependency, called sub-chains, where customers from one chain "bleed into" another chain causing "extraneous" queueing delays. The new approach described here changes approximate MVA by adjusting the population in a routing chain depending on the originating sub-chain. This new approach substantially reduces, or even eliminates, the extraneous queueing delay caused by the sub-chain dependent traffic. The approach was applied to a substantial model of an on-line bookstore, and reduced the overall error in queueing time by a factor of 20 times, when compared to simulation. The more accurate queueing estimates yield better results for the other outputs of the LQN solver.

To evaluate the value of lung ultrasound score (LUS) on assessing the severity and prognosis in patients with acute respiratory distress syndrome (ARDS), and to investigate its correlation with oxygenation index, acute physiology and chronic health evaluationII (APACHEII) score, sequential organ failure assessment (SOFA) score, and clinical pulmonary infection score (CPIS), and other traditional parameters.A prospective double-blind cohort study was conducted. Sixty-two ARDS patients conformed to the Berlin diagnostic criteria admitted to intensive care unit (ICU) of Beijing Huaxin Hospital from October 2013 to December 2014 were enrolled, including 14 cases with mild, 18 moderate, and 30 severe ARDS; among them 37 cases were of ARDS with pulmonary origin, and 25 non-pulmonary ARDS; 35 patients survived, and 27 died. The clinical data and scores of all patients were recorded by one specialized observer, including baseline data, hemodynamic parameters, lactate, respiratory parameters, and APACHEII, SOFA and CPIS scores. Another observer of recording was responsible for the results of lung ultrasound, LUS, and echocardiogram. The correlation between LUS and oxygenation index as well as APACHEII, SOFA and CPIS scores was analyzed by bivariate correlation analysis. Receiver operator characteristic curve (ROC) was plotted, and the predictive value, sensitivity and specificity of mild ARDS, moderate ARDS, severe ARDS and mortality by LUS were calculated.LUS had a negative correlation with oxygenation index (r=-0.755, P0.001), a good positive correlation with APACHEII (r=0.504, P0.001), SOFA (r=0.461, P0.001) and CPIS (r=0.571, P0.001) was found. LUS in the pulmonary ARDS group had a positive correlation with CPIS (r=0.399, P0.05), and a positive correlation was found in non-pulmonary ARDS group (r=0.350, P0.05), which indicated that the correlation in pulmonary ARDS was more satisfactory than that in non-pulmonary ARDS. LUS in the pulmonary ARDS group was significantly higher than that in non-pulmonary ARDS group (22.1±4.9 vs. 11.3±2.1, t=11.667, P0.001); LUS in mild, moderate, severe ARDS groups was 9.9±1.7, 14.0±1.4, 23.6±4.1. The predictive value for mild ARDS by LUS was 7.0, sensitivity of 87.0%, specificity of 89.0%; that for moderate ARDS was 11.0, sensitivity of 89.0%, specificity of 87.0%; that for severe ARDS was 8.0, sensitivity of 90.0%, specificity of 88.5%. LUS was 24.3±3.8 in the death group, and 12.7±2.9 in the survival group. Area under ROC curve (AUC) was calculated, and the patients with LUS19.0 had a high mortality, sensitivity for predicting death was 84.0%, and specificity of 89.0%.Bedside LUS, which is simple and easily available, could evaluate the changes in pulmonary ventilation area of ARDS, and its degree of severity, and prognosis including prediction of mortality of the patients.

Layered Queueing networks are a common method for solving performance models of modern distributed computer systems that use blocking remote procedure calls. Several analytic methods exist to solve these networks, many of which use the method of decomposition to break the model up into smaller, more easily solved submodels. Analytic solutions that break up a model must take into consideration interlocking, which is a phenomena that arises when a single customer in one submodel is represented by more than one customer in another. Failing to correct for interlocking can result in large errors in the final solution. This paper revisits interlocking, as implemented in the analytic Layered Queueing Network Solver. The interlock calculation it uses often distributes the waiting a customer experiences incorrectly among intermediate tasks. Further, certain models with external contention can yield unfeasible utilizations at interlocked servers. This paper introduces a new interlock calculation which is more accurate, and does not produce unfeasible utilizations. The new approach is compared against the old approach (and against solutions with no interlock correction) and is shown to produce better results in all cases.

Background NAD(P)H:quinone oxidoreductase (NQO1) is a flavoprotein that catalyzes two-electron reduction and detoxification of quinones and its derivatives. NQO1 catalyzes reactions that have a protective effect against redox cycling, oxidative stress and neoplasia. High expression of NQO1 is associated with many solid tumors including those affecting the colon, breast and pancreas; however, its role in the progression of ovarian carcinoma is largely undefined. This study aimed to investigate the clinicopathological significance of high NQO1 expression in serous ovarian carcinoma. Methods NQO1 protein expression was assessed using immunohistochemical (IHC) staining in 160 patients with serous ovarian carcinoma, 62 patients with ovarian borderline tumors and 53 patients with benign ovarian tumors. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect NQO1 mRNA expression levels. The correlation between high NQO1 expression and clinicopathological features of ovarian carcinoma was evaluated by Chi-square and Fisher’s exact test. Overall survival (OS) rates of all of ovarian carcinoma patients were calculated using the Kaplan-Meier method, and univariate and multivariate analyses were performed using the Cox proportional hazards regression model. Results NQO1 protein expression in ovarian carcinoma cells was predominantly cytoplasmic. Strong, positive expression of NQO1 protein was observed in 63.8% (102/160) of ovarian carcinomas, which was significantly higher than in borderline serous tumors (32.3%, 20/62) or benign serous tumors (11.3%, 6/53). Importantly, the rate of strong, positive NQO1 expression in borderline serous tumors was also higher than in benign serous tumors. High expression of NQO1 protein was closely associated with higher histological grade, advanced clinical stage and lower OS rates in ovarian carcinomas. Moreover, multivariate analysis indicated that NQO1 was a significant independent prognostic factor, in addition to clinical stage, in patients with ovarian carcinoma. Conclusions NQO1 is frequently upregulated in ovarian carcinoma. High expressin of NQO1 protein may be an effective biomarker for poor prognostic evaluation of patients with serous ovarian carcinomas.

Accumulating evidence indicated that aberrantly expressed microRNAs play critical roles in the initiation and progression of human cancers. However, the underlying functions of miR-493 in human melanoma remains unknown. Here, our study found that miR-493 expression was downregulated in human melanoma tissues and cells. Overexpression of miR-493 suppressed cell proliferation and cell cycle in human melanoma cell line A375. IRS4 was defined as a target for downregulation by miR-493 and was confirmed by luciferase assay. We also found that knockdown of IRS4 counteracted the proliferation promotion by miR-493 inhibitor. In summary, these results demonstrated that miR-493 acts as a tumor suppressor and inhibits cell proliferation and cell cycle in human melanoma by directly targeting IRS4.

Microbial fuel cells (MFCs) are devices that exploit microorganisms as biocatalysts to degrade organic matter or sludge present in wastewater (WW), and thereby generate electricity. We developed a simple, low-cost single-chamber microbial fuel cell (SCMFC)-type biochemical oxygen demand (BOD) sensor using carbon felt (anode) and activated sludge, and demonstrated its feasibility in the construction of a real-time BOD measurement system. Further, the effects of anodic pH and organic concentration on SCMFC performance were examined, and the correlation between BOD concentration and its response time was analyzed. Our results demonstrated that the SCMFC exhibited a stable voltage after 132 min following the addition of synthetic WW (BOD concentration: 200 mg/L). Notably, the response signal increased with an increase in BOD concentration (range: 5–200 mg/L) and was found to be directly proportional to the substrate concentration. However, at higher BOD concentrations (>120 mg/L) the response signal remained unaltered. Furthermore, we optimized the SCMFC using synthetic WW, and tested it with real WW. Upon feeding real WW, the BOD values exhibited a standard deviation from 2.08 to 8.3% when compared to the standard BOD5 method, thus demonstrating the practical applicability of the developed system to real treatment effluents.

In order to simulate the radar ground clutter at a low grazing angle and in middle or even low range resolution conditions, this paper summarizes a description of major electromagnetic mechanisms contributing to ground clutter, and presents detailed principles and simulation processes. First, we generate a radar cross section from a point target model. Then, a map with four types of terrain relief including deserts, farms, hills and towns are designed, through which the distributed ground clutter is obtained by empirical scattering coefficients given under each landcover. Finally, we generate the ground distributed clutter by back scattering coefficients spatial correlation model, in which the clutter amplitude is Rayleigh distribution and the power spectrum density obeys the Gaussian model. The clutter average Doppler shifting parameter in Gaussian distribution can be set and adjusted according to the realistic wind speed affecting the terrain area. Through the procedure of simulation, the experiment results show that in each type terrain of all four kinds of landscapes, the clutter amplitude distribution actually obeys Rayleigh model.

Layered Queueing Networks (LQN) have been used successfully by numerous researchers to solve performance models of multi-tier client server systems. A common approach for solving a LQN is to split the model up into a set of submodels, then employ approximate mean value analysis (AMVA) on each of these submodels in an interactive fashion and using the results from the solution of one submodel as inputs to the others. This paper addresses the performance of the layered queueing network solver, LQNS, in terms of submodel construction and in terms of changes to Bard-Schweitzer and Linearizer AMVA, in order to improve performance. In some of the models described in this paper, there is a difference in four orders of magnitude between the fastest and slowest approaches.

In order to measure the quality of Synthetic Aperture Radar (SAR) images, we propose an evaluation based on hypothesis testing consisting of a parametric and non-parametric scenario. Parametric hypothesis test includes the u test, chi-square test, and F test, etc. Non-parametric hypothesis test is composed of K-S test, and the Pearson test, etc. The measurement objects of SAR images are divided into point targets and distributed targets, where point targets criteria comprise spacial resolution, equivalent resolution, peak side-lobe ratio (PSLR), and integration side-lobe ratio (ISLR), etc. Distributed targets criteria are mean value, variance, equivalent number of looks (ENL) and radiometric resolution, etc. In experiments of real SAR images indoors and overseas, the measure ENL is selected as an example to test the image quality by the parametric hypothesis u test. The result shows that the presented method demonstrates the hypothesis test is feasible and applicable for SAR images quality evaluation.

The existing energy is almost provided by carbon-containing fossil sources such as oil and coal. The rapid consumption of these fossil resources causes an accelerated release of CO 2 which is a major cause of global warming and associated climate change. “Green” bio-methane (also named biogas) has the advantage for both reducing over dependency on fossil energy and reducing emissions o CO 2 and other greenhouse gases (GHGs). The purpose of this work is to introduce the biogas utilization ways widely applied in China and indicate the development orientation on clean, effective and economical utilizations. Firstly, biogas in china should gradually walk out from rural family, come into centralized anaerobic digestion (CAD). Secondly, combined production of heat and power (CHP) and upgrading to vehicle fuel should be popularized extensively. Thirdly, biogas fuel cell systems and biogas chemical industry (BCI) should be exploited as a technique reservation.

In recent years, new progress has been made in research of tumor markers. And namely tissue polypeptide specific antigen (TPS), cytokeratin 19-fragments (CYFRA21-1) and soluble tumor necrosis factor receptor (STNFR) are new tumor markers that have been used in clinical application. The aim of this study is to determine and compare the diagnostic value of 4 kinds of tumor markers, TPS, carcinoembryonic antigen (CEA), CYFRA21-1 and STNFR in patients with lung cancer.The serum levels of TPS, CEA, CYFRA21-1 and STNFR were determined in 72 patients with lung cancer, 54 patients with pulmonary benign diseases and 32 healthy adults by enzyme-linked immunosorbent assay (ELISA).The levels of the four tumor markers in lung cancer group were significantly higher than those in benign disease group (P0.005) and healthy control group (P0.001). Among the four markers, STNFR had the highest sensitivity (81.9%), CYFRA21-1 had the highest specificity (91.5%) and TPS had the highest accuracy (83.5%).TPS, CYFRA21-1 and STNFR can be used as very useful and sensitive tumor markers in the diagnosis of lung cancer, in which CYFRA21-1 may be the most useful tumor marker for clinical application.

Batch tests were carried out to investigate the effect of pH adjustment (control, 5.1, 5.8, 6.5, 7.2 and 7.9) on anaerobic fermentative products distribution for kitchen waste. The experimental results showed that H2 and CO2 were main gas products during the acidification stage (first 5 day) for all fermentations. After the acidification stage, fermentation type was dependent on pH. No gas produced due to the inhibition of low pH 4.5 for the control. It was hydrogen-producing fermentations when reactors operated at pH 5.0–5.5, while it was methane-producing fermentations when reactors operated at pH 6.0–7.0. The acidogenesis pathway was ethanol-type with a little volatile fatty acids (VFAs) production when the pH in reactors were lower than 5.5, while the acidogenesis pathway was VFAs-type without alcohols production when the pH in digesters were 6.0–7.0. The optimal pH value for VFAs production was 7.0 and it was about 4.5 for ethanol production. No ammonia inhibition was found in this study. The degradations of kitchen waste were inhibited by the high concentration of VFAs. The inhibitory levels of undissociated acids on acidogenesis were about 1185, 1150, 979, 460 and 178 mg/L at final actual pH 5.2, 5.4, 6.0, 6.5 and 7.0 for five fermentations with pH adjusting respectively.

In this paper, performance of microbial fuel cell constructed film A, film B and film C, with acetate as carbon source, potassium ferricyanide solution as the electron acceptor, has been studied. The capacity of the microbial fuel cell electrical performance was tested and several membrane microbial fuel cell cost-effective was analyzed. The results show that: maximum volume power density of membrane A is 3.45W/m3, the internal resistance is 56.08Ω; maximum volume power density of cell with membrane B 3.68W/m3, the internal resistance 49.13Ω; maximum volume power density of cell with membrane C 8.25W/m3, internal resistance 26.59V. Comparing the performance, film A, film B is a bit weak, but the film A, film B are on the absolute advantage in price. With the membrane in-depth study, cost-effective good films for industrial applications in microbial fuel cells is feasible.

Fair-share scheduling attempts to grant access to a resource based on the amount of “share” that a task possesses. It is widely used in places such as Internet routing, and recently, in the Linux kernel. Software performance engineering is concerned with creating responsive applications and often uses modeling to predict the behaviour of a system before the system is built. This work extends the Layered Queueing Network (LQN) performance model used to model distributed software systems by including hierarchical fair-share scheduling with both guarantees and caps. To exercise the model, the Completely Fair Scheduler, found in recent Linux kernels, is incorporated into PARASOL, the underlying simulation engine of the LQN simulator, lqsim. This simulator is then used to study the effects of fair-share scheduling on a multi-tier implementation of a building security system. The results here show that fair-share scheduling with guarantees is not sufficient when an application is layered into multiple tiers because of contention at lower layers in the system. Fair-share scheduling with caps must be used instead.

A pilot scale of 200 t/year biodiesel production system was setup to test the different feedstock oil for their feasibility of being biodiesel feedstock in China. The tested oil include: rapeseed oil, Chinese wood oil, trap grease. Meanwhile the optimum operating conditions for a plug flow reactor to convert transesterification reaction was investigated in this study. They were found to be as follows: the catalyst dosage is 1.2 wt%; the residence time is about 17min; the bed temperature is 65 °C ; the oil/methanol ratio is 1:6; the content of methyl ester is 96.33% under these conditions. A kind of an ion exchange resin filled in the fixed bed reactor was used as the esterification catalyst for the pretreating of high-acidified oil. The acid value of the oil could be reduced from 7 to 0.8 mgKOH·g-1 after 88 min. Also a kind of acidified oil with the acid value being 114 mg KOH·g-1 could be equally converted to a good biodiesel product through this system. Generally, the refined biodiesel product generated through this system could meet China #0 biodiesel standard, as well as Germany biodiesel standard for most indexes. It indicates that the designed process in this system has a good adaptability for different kinds of oil.

OBJECTIVE To introduce a new broken pedicle screw fragment retrieval instrument, and evaluate its clinical viability and effectiveness. METHODS Following basic retrieval contrivance of broken pedicle screws described in literature, a new retrieval instrument was designed and developed; introducing its mechanism, technical components, and use. This innovative apparatus proved successful not only in saw bone and cadaver trials but in 10 clinical cases as well. RESULTS This particular unique instrument successfully retrieves broken pedicle screw fragments through original passage backing out the screw with preservation of pedicle integrity while maintaining pedicle biomechanics. No complications were observed. CONCLUSIONS With solid scientific theoretical planning and experimentation, the new retrieval instrument design proved clinical practicality and efficacy.

To investigate the treatment of infected total knee arthroplasty (TKA).Between 1983 and 2000, 6 patients with infection after TKAs were treated, including 2 men and 4 women, aged on average 63 years (44 - 75 years). Initial knee arthroplasty was performed for osteoarthritis in 4 patients and for rheumatoid arthritis in 2 knees. The timing of diagnosis of infection after knee arthroplasty averaged 50 months (range, 1 month-11 years). Simple debridement and antibiotic treatment were prescribed for 3 patients, debridement and one-stage reimplantation for 1, debridement and two-stage reimplantation for 1, and athrodesis for 1.Of the 3 patients with simple debridement, one was cured, one failed but underwent athrodesis later, and one lost to follow up. Two patients with reimplantation were cured and had good function recovery. All of the 6 patients were followed up on average for 4 years. No infection recurred except one who lost to follow-up.Management of infection after total knee arthroplasty includes antibiotic suppression and debridement with prosthesis retention, insertion of another prosthesis as a one-stage or two-stage exchange technique, knee arthrodesis and amputation. These treatments have specific indications. To treat infection after total knee arthroplasty, suitable method should be taken according to patient's condition. Arthrodesis is the best salvage operation, though it may handicap patients' daily life. Reimplantation of another prosthesis could maintain a functional joint.