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Electrostatically driven torsional micromirrors are suitable for optical microelectromechanical systems due to their good dynamic response, low adhesion, and simple structure for large-scale-integrated applications. For these devices, how to eliminate the excessive residual vibration in order to achieve more accurate positioning and faster switching is an important research topic. Because of the known nonlinearity issues, traditional shaping techniques based on linear theories are not suitable for nonlinear torsional micromirrors. In addition, due to the difficulties in calculating energy dissipation, the existing nonlinear command shaping techniques using energy method have neglected the effect of damping. We analyze the static and dynamic behavior of the electrostatically actuated torsional micromirrors. Based on the response of these devices, a multistep-shaping control considering the damping effects and the nonlinearity is proposed. Compared to the conventional closed-loop control, the proposed multistep-shaping control is a feedforward approach which can yield a good enough performance without extra sensors and actuators. Simulation results show that, without changing the system structure, the preshaping input reduces the settling time from 4.3 to 0.97 ms, and the overshoot percentage of the mirror response is decreased from 33.2% to 0.2%. [ABSTRACT FROM AUTHOR]

Background Nickel (Ni) is an essential micronutrient; however, its metabolic or physiological functions in plants and animals are largely uncharacterized. The ribonucleases (RNase, e.g., RNase A) are a large family of hydrolases found in one form or many forms facilitating nitrogen (N) cycling. It is currently unknown how either a deficiency or excess of Ni influences the functionality of ribonucleases, like RNase A. This is especially true for perennial crops possessing relatively high Ni requirements. Results We report that the 'rising' xylem sap of pecan [Carya illinoinensis (Wangenh.) K. Koch, a long-lived tree] at bud break contains a 14 kDa RNase A (aka, RNase 1), which amount has a 33% greater in Ni-deficient as in Ni-sufficient trees when exposed to Ni ions exhibits ureolytic activity. The homologous 13.4 kDa bovine pancreatic RNase A likewise exhibits ureolytic activity upon exposure to Ni ions. Ni therefore affects enzymatic function of a typically non-metalloenzyme, such as it transforms to an enzyme capable of hydrolyzing a linear amide; thus, converting an endonuclease esterase into a urease. Conclusions We conclude that Ni potentially affects the level and activity of RNase A present in the spring xylem sap of pecan trees, and probably in other crops, it has the same influence. The catalytic property of RNase A appears to shift from a nuclease to a urease relying on Ni exposure. This is suggestive that RNase A might possess novel metabolic functionality regarding N-metabolism in perennial plants. The ability of Ni to convert the activity of plant and animal RNase A from that of a ribonuclease to a urease indicates a possible unrecognized beneficial metabolic function of Ni in organisms, while also identifying a potential detrimental effect of excessive Ni on N related metabolic activity if there is sufficient disruption of Ni homeostasis. [ABSTRACT FROM AUTHOR]

We studied the effects of isoquinoline alkaloid neferine (Nef) extracted from the seed embryo of Nelumbo nucifera Gaertn on Human ether-à-go-go-related gene (HERG) channels stably expressed in human embryonic kidney (HEK293) cells using whole-cell patch clamp technique, western blot analysis and immunofluorescence experiment. Nef induced a concentration-dependent decrease in current amplitude according to the voltage steps and tail currents of HERG with an IC50 of 7.419 μM ( nH −0.5563). Nef shifted the activation curve in a significantly negative direction and accelerated recovery from inactivation and onset of inactivation, however, slowed deactivation. In addition, it had no significant influence on steady-state inactivation curve. Western blot and immunofluorescence results suggested Nef had no significant effect on the expression of HERG protein. In summary, Nef can block HERG K+ channels that functions by changing the channel activation and inactivation kinetics. Nef has no effect on the generation and trafficking of HERG protein. A blocked-off HERG channel was one mechanism of the anti-arrhythmic effects by Nef. [ABSTRACT FROM AUTHOR]

Dust collection efficiency data were analyzed to determine better operating conditions for a two-dimensional circulating granular bed filter (CGBF). The dust collection efficiency in the granular bed was affected by the following operating parameters: the louver angle, the solids mass flow rate, and the particle size of the bed material. Experimental results showed that higher dust collection efficiency occurs when the solids mass flow rates were 20.34 ± 0.24, 21.50 ± 0.11, and 30.51 ± 0.57 g/sec at louver angles of 45°, 30°, and 20°, respectively. Optimal dust collection efficiency peaked with a louver angle of 30°. Average particle sizes of bed material by sieve diameters (µm) of 795 µm had higher dust collection efficiency than the average collector particle size of 1500 µm. Dust collection efficiency is influenced by bed material attrition phenomenon, causing dust collection efficiency to decrease rapidly. The dust collection efficiency analysis not only found the system free of design defects but also assisted in the operation of the two-dimensional CGBF system. [ABSTRACT FROM AUTHOR]

The existence of nickel (Ni) deficiency is becoming increasingly apparent in crops, especially for ureide-transporting woody perennials, but its physiological role is poorly understood. We evaluated the concentrations of ureides, amino acids, and organic acids in photosynthetic foliar tissue from Ni-sufficient (Ni-S) versus Ni-deficient (Ni-D) pecan (Carya illinoinensis [Wangenh.] K. Koch). Foliage of Ni-D pecan seedlings exhibited metabolic disruption of nitrogen metabolism via ureide catabolism, amino acid metabolism, and ornithine cycle intermediates. Disruption of ureide catabolism in Ni-D foliage resulted in accumulation of xanthine, allantoic acid, ureidoglycolate, and citrulline, but total ureides, urea concentration, and urease activity were reduced. Disruption of amino acid metabolism in Ni-D foliage resulted in accumulation of glycine, valine, isoleucine, tyrosine, tryptophan, arginine, and total free amino acids, and lower concentrations of histidine and glutamic acid. Ni deficiency also disrupted the citric acid cycle, the second stage of respiration, where Ni-D foliage contained very low levels of citrate compared to Ni-S foliage. Disruption of carbon metabolism was also via accumulation of lactic and oxalic acids. The results indicate that mouse-ear, a key morphological symptom, is likely linked to the toxic accumulation of oxalic and lactic acids in the rapidly growing tips and margins of leaflets. Our results support the role of Ni as an essential plant nutrient element. The magnitude of metabolic disruption exhibited in Ni-D pecan is evidence of the existence of unidentified physiological roles for Ni in pecan. [ABSTRACT FROM AUTHOR]

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[Objective] The paper was to study pathogenic mechanism and action mode of Bacillus thuringiensis (Bt) 00-50-5 strain against Trichoplusia ni Hubner. [Method] The crystals and spores of B. thuringiensis 00-50-5 strain were first isolated and purified, and their insecticidal activities against T. ni were compared. [Result] Either the mixture of pure crystals and pure spores of 00-50-5 strain, or only pure crystals could kill T. ni larvae under the concentration of 100 μg/mL after 48 h, and the mortality rate reached 100% ; pure spores could not kill the larvae. Determination results of median lethal concentration showed that insecticidal activity of pure crystal of Bt 00-50-5 strain (LC50 =0.32 μg/mL) was higher than the mixture of crystals and spores (LC50 =0.48) , but the insecticidal activity of pure spores was very low (LC50500.00). Therefore, the crystals were primarily responsible for causing death of larvae. [Conclusion] The paper provides theoretical basis for application of Bt 00-50-5 strain. [ABSTRACT FROM AUTHOR]

Presents a corrected reprint of an article titled "Crystallization and preliminary X-ray diffraction studies of monomeric isocitrate dehydrogenase from Corynrbacterium glutamicum," published in a previous issue of the periodical "Acta Crystallographica: Section D."

Rapid growth of tumor cells needs to consume large amounts of oxygen and glucose, due to lack of blood supply within the tumor, cells live in an environment that lack of oxygen and nutrients. This environment results in endoplasmic reticulum (ER) stress and activates the UPR (unfolded protein response). More and more evidence suggests UPR provides a growth signal pathway required for tumor growth. In the present study, we investigated the relationship between XBP1, one transcription factor in UPR, and the expression of LOX. We found that ER stress induces high expression of XBP1, one transcription factor in UPR, in both 2D culture and 3D culture; but only promotes growth of lung adenocarcinoma cells in in vitro 3D culture other than 2D culture. In 3D culture, we further showed that knockdown XBP1 expression can block Tm/Tg-induced cell growth. LOX genes may be key downstream effector of XBP1. Knockdown LOX expression can partially block XBP1-induced cell growth. Then we showed XBP1 suppressed by RNA interference (RNAi) can reduce the expression of LOX. For the first time, it is being shown that XBP1 can regulate the expression of LOX to promote cell growth.

Background and Objectives: The objective of this study is to explore clinical risk factors for venous thromboembolism (VTE) in postoperative lung cancer patients in order to provide a basis for the prevention and treatment of postoperative VTE., Methods: A total of 1,001 lung cancer patients were retrospectively analyzed. Each patient was confirmed with surgical pathology diagnosis and had a complete clinical and follow-up record. VTE was identified in a combination of spiral computed tomography (CT), pulmonary angiography, and color Doppler ultrasound. We used life table method to create an occurrence frequency curve of thrombosis. We also searched for high risk factors for postoperative VTE with Cox multivariate regression model and created frequency curves of thrombosis against different risk factors using Kaplan-Meier method., Results: As of July 31, 2011, the median follow-up time is 25.73 ± 0.11 months (19.23-31.37). The cumulative frequency of VTE among 1,001 lung cancer patients is 2%, 3%, 4%, 5%, and 5.3% over 1, 3, 6, 12, and 30 months after the surgery. COX regression analysis showed that the hazard ratio of VTE occurrence in patients with incomplete resection relative to ones with complete resection is 9.867 (95% CI: 5.275-18.459, P = 0.000). And the hazard ratio of VTE occurrence is 3.472 (95% CI: 1.761-6.845, P = 0.000) in patients with anti-angiogenesis treatment compared to patients without such treatment. The hazard ratio of VTE occurrence is 2.808 (95% CI: 1.439-5.479, P = 0.002) in patients with EGFR-TKI treatment relative to patients without the treatment, and 7.520 (95% CI: 3.968-14.250, P = 0.000) in patients with an increase in D-dimer level relative to normal ones, Conclusions: The highest incidence of VTE is within 1 month after lung cancer surgery. High risk factors for VTE include incomplete surgical resection, postoperative use of anti-angiogenesis drugs, EGFR-TKI application and an increase in preoperative D-dimer level., (Copyright © 2012 Wiley Periodicals, Inc.)

Objective: To explore the role and mechanism of motilin in colonic motility disorder., Methods: A total of 20 male Wistar rats (180 - 200 g) were randomly divided into 2 groups: water avoidance stress (WAS, n = 10) and sham water avoidance stress (SWAS, n = 10). Rats were exposed to 1 h WAS or SWAS daily for 10 consecutive days. Motilin in plasma was measured by enzyme-linked immunosorbent assay (ELISA). Proximal colon circular smooth muscle cells (PCSM) were isolated by enzymatic digestion and L-type calcium currents (ICa(L)) recorded by patch-clamp techniques., Results: The fecal pellets during 1 h WAS significantly increased (5.4 ± 1.0 vs 2.4 ± 0.7, P < 0.01, n = 10). The motilin in plasma had significant difference between WAS rats and SWAS rats ((135 ± 35) vs (89 ± 24) pg/ml, P < 0.01, n = 10). The ICa(L) of two rats had no significant difference. But 6 × 10(-5) mmol/L motilin increased ICa(L) more in WAS than in SWAS rats at 0 mV ((1.6 ± 0.4) vs (1.0 ± 0.3) pA/pF, P < 0.05, n = 10)., Conclusion: WAS leads to elevated motilin levels in plasma and active L-type Ca(2+) channels in colon. And it contributes to colonic motility disorder.

Interleukin-33 (IL-33) is implicated in rheumatoid arthritis with effects of promoting tumor necrosis factor-alpha (TNF-α) and interleukin-17 (IL-17) productions, which have been demonstrated to play a pivotal role in ankylosing spondylitis (AS). However, changes of IL-33 levels and its effects in AS have not been investigated. Eighty-nine and 178 healthy controls were included in the current study. Erythrocyte sedimentation rate, serum levels of C-reactive protein, IL-17, and IL-33 were determined. Effects of IL-33 on TNF-α and IL-6 productions were investigated. Effects of IL-33 on neutrophil migration were also evaluated. Serum levels of IL-33 were elevated in AS patients. Moreover, IL-33 was significantly higher in active AS patients according to Bath Ankylosing Spondylitis Disease Activity Index. IL-33 concentrations in serum were positively correlated with TNF-α and IL-17 levels (IL-33 and TNF-α, r = 0.54, P < 0.01; IL-33 and IL-17, r = 0.47, P < 0.01). IL-33 dose-dependently enhanced TNF-α and IL-6 productions by peripheral blood mononuclear cells (PBMCs) responding to lipopolysaccharide. IL-33 induced neutrophil migration only in higher doses (≥10 ng/ml). Serum levels of IL-33 were elevated in AS patients. IL-33 may play a role in AS development via enhancing TNF-α production by PBMCs and inducing neutrophil migration.

Objective: To evaluate the efficacy of short-term intermittent prophylactic use of a recombinant human thrombopoietin (rhTPO) in chemotherapy-induced severe thrombocytopenia in lung cancer patients., Methods: 24 advanced non-small cell lung cancer (NSCLC) patients who experienced severe thrombocytopenia in the last chemotherapy cycle received prophylactic rhTPO treatment in the next chemotherapy cycle (prophylactic treated cycle, PTC). rhTPO was given subcutaneously 300 U×kg(-1)×d(-1) on days 2, 4, 6, and 9 after the initiation of chemotherapy. Platelet count was monitored and compared with that in the previous treatment cycle (control cycle, CC)., Results: The lowest platelet count in the prophylactic rhTPO cycle was significantly higher than that in control cycle [(56 ± 16) × 10(9)/L vs. (28 ± 13) × 10(9)/L, P < 0.001]. The duration of thrombocytopenia was also shortened by the prophylactic rhTPO [(8 ± 2) d vs. (12 ± 3) d, P < 0.001]. The area under curve (AUC) of platelet count (21 days) was significantly increased [(3517 ± 685) × 10(9)/L vs. (2063 ± 436) × 10(9)/L, P < 0.001]. The time to platelet nadir and peak was not affected., Conclusion: Prophylactic use of rhTPO can attenuate the severity and shorten the duration of chemotherapy-induced thrombocytopenia in lung cancer patients.

This study identifies the natural background, anthropogenic background and distribution of contamination caused by heavy metal pollutants in soil in Chunghua County of central Taiwan by using a finite mixture distribution model (FMDM). The probabilities of contaminated area distribution are mapped using single-variable indicator kriging and multiple-variable indicator kriging (MVIK) with the FMDM cut-off values and regulation thresholds for heavy metals. FMDM results indicate that Cr, Cu, Ni and Zn can be individually fitted by a mixture model representing the background and contamination distributions of the four metals in soil. The FMDM cut-off values for contamination caused by the metals are close to the regulation thresholds, except for the cut-off value of Zn. The receiver operating characteristic (ROC) curve validates that indicator kriging and MVIK with FMDM cut-off values can reliably delineate heavy metals contamination, particularly for areas lacking background information and high heavy metal concentrations in soil.

We studied the effects of isoquinoline alkaloid neferine (Nef) extracted from the seed embryo of Nelumbo nucifera Gaertn on Human ether-à-go-go-related gene (HERG) channels stably expressed in human embryonic kidney (HEK293) cells using whole-cell patch clamp technique, western blot analysis and immunofluorescence experiment. Nef induced a concentration-dependent decrease in current amplitude according to the voltage steps and tail currents of HERG with an IC(50) of 7.419 microM (n(H) -0.5563). Nef shifted the activation curve in a significantly negative direction and accelerated recovery from inactivation and onset of inactivation, however, slowed deactivation. In addition, it had no significant influence on steady-state inactivation curve. Western blot and immunofluorescence results suggested Nef had no significant effect on the expression of HERG protein. In summary, Nef can block HERG K(+) channels that functions by changing the channel activation and inactivation kinetics. Nef has no effect on the generation and trafficking of HERG protein. A blocked-off HERG channel was one mechanism of the anti-arrhythmic effects by Nef.

Objective: To investigate the incidence, survival, and influential factors of lung cancer in the Shanghai populations., Methods: Data of individual cases of lung cancer 2000 - 2004 were obtained from the Shanghai Cancer registry System. The annual prevent change (APC) of incidence of lung cancer from 1972 to 2004 was calculate by crude and standardized rates so as to analyze the time trends. Cox proportional risk model was used to analyze the factors influencing the survival., Results: 23,196 new cases of lung cancer were diagnosed 2002 - 2004. The crude incidence rate of lung cancer in the females was 33.73/100,000, and the age-adjusted rate was 30.90/100,000. The crude incidence rate of lung cancer and the age-adjusted rate for the males were 81.65/100,000 and 33.73/100,000 respectively, both higher than those of females. The APC values of crude incidence 2004 for both the males and females increased by 1.723% and 2.036% respectively in comparison with the values 1972 (both P < 0.01). The age-adjusted APC of standardized incidence rate for the males in the city center was -0.605% (P < 0.01), showing a tendency to reduce; while the age-adjusted APC of standardized incidence rate for the females in the city center was -0.136 (P > 0.05). The proportion of stage IV cases in the females was 47.5%, significantly higher than that in the males (40.0%, P < 0.05). The proportion of adenocarcinoma in the females was 86.1%, significantly higher than that in the males (47.8%, P < 0.05). The 3-year survival rate and median survival time of adenocarcinoma in the females were 30.38% and 1.48 years respectively, both significantly higher than those in the males (22.66% and 0.98 years, both P < 0.01). Female gender, being younger, living in urban area, squamous cancer, early stage, visit to higher-grade hospital were the factors beneficial to the prognosis of lung cancer., Conclusion: The age adjusted incidence rate of lung cancer in Shanghai is much closer to that of Western Europe and North America. The beneficial factors for higher survival rate are female, younger age, urban residency, squamous cell lung cancer, earlier stage of diagnosis, and higher grade hospital for treatment. Women have statistically better outcomes than men in different stages of disease.

The effect of carbon properties and water characteristics on the adsorption of m-LR by activated carbon was evaluated using kinetic and isotherm tests. The results showed that both physical and chemical effects simultaneously affect the adsorption process. The activated carbon with a high ratio of mesopore and macropore volume showed an increased m-LR adsorption capacity. The micropores in carbon offer only a nominal internal surface for adsorption. The adsorption capabilities of different activated carbon generally followed their pH(zpc) values. Activated carbons with higher pH(zpc) values exhibit a neutral or positive charge under typical pH conditions, promoting m-LR adsorption on the carbon surface. The competitive effects of natural organic matter (NOM) on activated carbon were evaluated and showed that caused a reduction in the capacity of carbon for m-LR. Furthermore, when pre-chlorination was preceded by adsorption, then the residual chlorine would react with activated carbon caused a decrease in sorption capacity of m-LR, while that chlorine at normal treatment plant dosages is not effective for degrading m-LR.

Consumers generally concern taste and odor in drinking water. In the Southern Taiwan, more than 5,000,000 people are suffered from earth/musty odor in drinking water, especially in the summer. Thus, ozonation of geosmin (GSM), 2-methylisoborneol (2-MIB), and 2-furfural (2-FF) in eutrophic surface waters has been studied in the present work. Experimentally, it was found that the water contained high dissolved organic carbon (DOC), humic substances, and specific ultraviolet absorbance (SUVA) resulting the highly ozone (O3) demand. The natural organic matters (NOM) in the waters had a significant effect on the ozonation of GSM, 2-MIB and 2-FF. Their destruction rates were increased with high contents of aromatics, phenolics, and SUVAs. In addition, during ozonation of raw waters, O3 and OH. played an important role in destruction of algae cells and caused excretion of extracellular organic matter (EOM) to the bulk phase.

Objective: To study the synthesis, cloning, expression and antigenicity of therapeutic multi-epitope gene of hepatitis B virus., Methods: The therapeutic multi-epitope gene of hepatitis B virus was synthesized and cloned into the vector pWR450-1, then was expressed in E.coli and the products were purified. The immunogenicity of the expressed protein was analyzed by Western-blotting., Results: Recombinant plasmid PWR/BPT was constructed successfully and the protein of multi-epitope gene of hepatitis B virus was expressed in E. coli, which showed ideal antigenicity by Western-blotting., Conclusions: The designed multi-epitope therapeutic gene of hepatitis B virus was proved to be correct and the expressed protein may be a good therapeutic vaccine.

Ricin-containing galactosyl ceramide liposomes (ricin-GCLs) lyophilized product was made by the dehydration-rehydration vesicles(DRV) method and its toxicity to human heptocarcinoma cell line 7721 and to mice was investigated. The results indicated that the maximum encapsulation efficiency of ricin was 74.1%. The distribution of ricin-GCLs' sizes accords with intravenous injection standard and changes little in half a year at 4 degrees. In the cytotoxicity assay, the ratio of ricin-GCLs' to free ricin's IC50 was 1.00:3.89, which indicated that the ricin entrapped in GCLs was more effective than the free one in killing human heptocarcinoma cell line 7721. In vivo, the mice's LD(50) of ricin-GCLs ((41.8+/-9.33) &mgr;g/kg)is more than that of free ricin ((30.6+/-8.49) &mgr;g/kg) by 36.29%. So, ricin entrapped in GCLs promotes its cytotoxicity and reduces its toxic side-effect.