988 resultados para All terrain bicycles -- Shock absorbers
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Mode of access: Internet.
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National Highway Traffic Safety Administration, Washington, D.C.
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National Highway Traffic Safety Administration, Washington, D.C.
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National Highway Traffic Safety Administration, Office of Research and Development, Washington, D.C.
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Shipping list no.: 90-548-P.
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Throughout the 1970s and 1980s, West Germany was considered to be one of the world’s most successful economic and political systems. In his seminal 1987 analysis of West Germany’s ‘semisovereign’ system of governance, Peter Katzenstein attributed this success to a combination of a fragmented polity, consensus politics and incremental policy changes. However, unification in 1990 has both changed Germany’s institutional configuration and created economic and social challenges on a huge scale. This volume therefore asks whether semisovereignty still exists in contemporary Germany and, crucially, whether it remains an asset in terms of addressing these challenges. By shadowing and building on the original study, an eminent team of British, German and American scholars analyses institutional changes and the resulting policy developments in key sectors, with Peter Katzenstein himself providing the conclusion. Together, the chapters provide a landmark assessment of the outcomes produced by one of the world’s most important countries. Contents: 1. Introduction: semisovereignty challenged Simon Green and William E. Paterson; 2. Institutional transfer: can semisovereignty be transferred? The political economy of Eastern Germany Wade Jacoby; 3. Political parties Thomas Saalfeld; 4. Federalism: the new territorialism Charlie Jeffery; 5. Shock-absorbers under stress. Parapublic institutions and the double challenges of German unification and European integration Andreas Busch; 6. Economic policy management: catastrophic equilibrium, tipping points and crisis interventions Kenneth Dyson; 7. Industrial relations: from state weakness as strength to state weakness as weakness. Welfare corporatism and the private use of the public interest Wolfgang Streeck; 8. Social policy: crisis and transformation Roland Czada; 9. Immigration and integration policy: between incrementalism and non-decisions Simon Green; 10. Environmental policy: the law of diminishing returns? Charles Lees; 11. Administrative reform Kluas H. Goetz; 12. European policy-making: between associated sovereignty and semisovereignty William E. Paterson; 13. Conclusion: semisovereignty in United Germany Peter J. Katzenstein.
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This research focuses on developing active suspension optimal controllers for two linear and non-linear half-car models. A detailed comparison between quarter-car and half-car active suspension approaches is provided for improving two important scenarios in vehicle dynamics, i.e. ride quality and road holding. Having used a half-car vehicle model, heave and pitch motion are analyzed for those scenarios, with cargo mass as a variable. The governing equations of the system are analysed in a multi-energy domain package, i.e., 20-Sim. System equations are presented in the bond-graph language to facilitate calculation of energy usage. The results present optimum set of gains for both ride quality and road holding scenarios are the gains which has derived when maximum allowable cargo mass is considered for the vehicle. The energy implications of substituting passive suspension units with active ones are studied by considering not only the energy used by the actuator, but also the reduction in energy lost through the passive damper. Energy analysis showed less energy was dissipated in shock absorbers when either quarter-car or half-car controllers were used instead of passive suspension. It was seen that more energy could be saved by using half-car active controllers than the quarter-car ones. Results also proved that using active suspension units, whether quarter-car or half-car based, under those realistic limitations is energy-efficient and suggested.
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Hsp90 is a molecular chaperone essential for cell viability in eukaryotes that is associated with the maturation of proteins involved in important cell functions and implicated in the stabilization of the tumor phenotype of various cancers, making this chaperone a notably interesting therapeutic target. Celastrol is a plant-derived pentacyclic triterpenoid compound with potent antioxidant, anti-inflammatory and anticancer activities; however, celastrol's action mode is still elusive. In this work, we investigated the effect of celastrol on the conformational and functional aspects of Hsp90α. Interestingly, celastrol appeared to target Hsp90α directly as the compound induced the oligomerization of the chaperone via the C-terminal domain as demonstrated by experiments using a deletion mutant. The nature of the oligomers was investigated by biophysical tools demonstrating that a two-fold excess of celastrol induced the formation of a decameric Hsp90α bound throughout the C-terminal domain. When bound, celastrol destabilized the C-terminal domain. Surprisingly, standard chaperone functional investigations demonstrated that neither the in vitro chaperone activity of protecting against aggregation nor the ability to bind a TPR co-chaperone, which binds to the C-terminus of Hsp90α, were affected by celastrol. Celastrol interferes with specific biological functions of Hsp90α. Our results suggest a model in which celastrol binds directly to the C-terminal domain of Hsp90α causing oligomerization. However, the ability to protect against protein aggregation (supported by our results) and to bind to TPR co-chaperones are not affected by celastrol. Therefore celastrol may act primarily by inducing specific oligomerization that affects some, but not all, of the functions of Hsp90α. To the best of our knowledge, this study is the first work to use multiple probes to investigate the effect that celastrol has on the stability and oligomerization of Hsp90α and on the binding of this chaperone to Tom70. This work provides a novel mechanism by which celastrol binds Hsp90α.
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Septic shock is a severe inflammatory state caused by an infectious agent. Our purpose was to investigate serum amyloid A (SAA) protein and C-reactive protein (CRP) as inflammatory markers of septic shock patients. Here we evaluate 29 patients in postoperative period, with septic shock, in a prospective study developed in a surgical intensive care unit. All eligible patients were monitored over a 7-day period by sequential organ failure assessment (SOFA) score, daily CRP, SAA, and lactate measurements. CRP and SAA strongly correlated up to the fifth day of observation but were not good predictors of mortality in septic shock. Copyright (C) 2008.
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The aim of this work was to investigate the effect of different feeding times (2, 4, and 6 h) and organic loading rates (3, 6 and 12 gCOD l(-1) day(-1)) on the performance of an anaerobic sequencing batch reactor containing immobilized biomass, as well as to verify the minimum amount of alkalinity that can be added to the influent. The reactor, in which mixing was achieved by recirculation of the liquid phase, was maintained at 30 +/- 1A degrees C, possessed 2.5 l reactional volume and treated 1.5 l cheese whey in 8-h cycles. Results showed that the effect of feeding time on reactor performance was more pronounced at higher values of organic loading rates (OLR). During operation at an OLR of 3 gCOD l(-1) day(-1), change in feeding time did not affect efficiency of organic matter removal from the reactor. At an OLR of 6 gCOD l(-1) day(-1), reactor efficiency improved in relation to the lower loading rate and tended to drop at longer feeding times. At an OLR of 12 gCOD l(-1) day(-1) the reactor showed to depend more on feeding time; higher feeding times resulted in a decrease in reactor efficiency. Under all conditions shock loads of 24 gCOD l(-1) day(-1) caused an increase in acids concentration in the effluent. However, despite this increase, the reactor regained stability readily and alkalinity supplied to the influent showed to be sufficient to maintain pH close to neutral during operation. Regardless of applied OLR, operation with feeding time of 2 h was which provided improved stability and rendered the process less susceptible to shock loads.
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Safe application of the anaerobic sequencing biofilm batch reactor (ASBBR) still depends on deeper insight into its behavior when faced with common operational problems in wastewater treatments such as tolerance to abrupt variations in influent concentration, so called shock loads. To this end the current work shows the effect of organic shock loads on the performance of an ASBBR, with a useful volume of 5 L, containing 0.5-cm polyurethane cubes and operating at 30 degrees C with mechanical stirring of 500 rpm. In the assays 2 L of two types of synthetic wastewater were treated in 8-h cycles. Synthetic wastewater I was based on sucrose-amide-cellulose with concentration of 500 mg COD/L and synthetic wastewater II was based on volatile acids with concentration ranging from 500 to 2000 mg COD/L. Organic shock loads of 2-4 times the operation concentration were applied during one and two cycles. System efficiency was monitored before and after application of the perturbation. When operating with concentrations from 500 to 1000 mg COD/L and shock loads of 2-4 times the influent concentration during one or two cycles the system was able to regain stability after one cycle and the values of organic matter, total and intermediate volatile acids, bicarbonate alkalinity and pH were similar to those prior to the perturbations. At a concentration of 2000 mg COD/L the reactor appeared to be robust, regaining removal efficiencies similar to those prior to perturbation at shock loads twice the operation concentration lasting one cycle and stability was recovered after two cycles. However, for shock loads twice the operation concentration during two cycles and shock loads four times the operation concentration during one or two cycles filtered sample removal efficiency decreased to levels different from those prior to perturbation, on an average of 90-80%, approximately, yet the system managed to attain stability within two cycles after shock application. Therefore, this investigation envisions the potential of full scale application of this type of bioreactor which showed robustness to organic shock loads, despite discontinuous operation and the short times available for treating total wastewater volume. (c) 2007 Elsevier Ltd. All rights reserved.
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The heat sensitivity of photochemical processes was evaluated in the common bean (Phaseolus vulgaris) cultivars A222, A320, and Carioca grown under well-watered conditions during the entire plant cycle (control treatment) or subjected to a temporal moderate water deficit at the preflowering stage (PWD). The responses of chlorophyll fluorescence to temperature were evaluated in leaf discs excised from control and PWD plants seven days after the complete recovery of plant shoot hydration. Heat treatment was done in the dark (5 min) at the ambient CO2 concentration. Chlorophyll fluorescence was assessed under both dark and light conditions at 25, 35, and 45 degrees C. In the dark, a decline of the potential quantum efficiency of photosystem II (PSII) and an increase in minimum chlorophyll fluorescence were observed in all genotypes at 45 degrees C, but these responses were affected by PWD. In the light, the apparent electron transport rate and the effective quantum efficiency of PSII were reduced by heat stress (45 degrees C), but no change due to PWD was demonstrated. Interestingly, only the A222 cultivar subjected to PWD showed a significant increase in nonphotochemical fluorescence quenching at 45 degrees C. The common bean cultivars had different photochemical sensitivities to heat stress altered by a previous water deficit period. Increased thermal tolerance due to PWD was genotype-dependent and associated with an increase in potential quantum efficiency of PSII at high temperature. Under such conditions, the genotype responsive to PWD treatment enhanced its protective capacity against excessive light energy via increased nonphotochemical quenching.
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In a randomized trial involving 71 postmenopausal osteoporotic women with vertebral compression fractures, radiocalcium absorption studies using the Ca-45 single isotope method (alpha) were performed at baseline and after 8 months of treatment with either continuous combined hormone replacement therapy (HRT, as piperazine estrone sulfate 0.625-0.937mg daily +/- medroxyprogesterone acetate 2.5 mg daily depending on uterine status) or HRT plus calcitriol 0.25 mu g twice daily. A calcium supplement of 600 mg nocte was given to only those women who had a daily calcium intake of less than 1 g per day at baseline, as assessed by recalled dietary intake. There was a significant decrease 0.74 (+/- 0.35 SD) to 0.58 (+/- 0.22), Delta alpha = -0.17 (+/- 0.26), p<0.0005] in alpha at 8 months compared with baseline in the HRT-treated group, but a significant increase [0.68 (+/- 0.31) to 0.84 (+/- 0.27), Delta alpha = +0.16 (+/- 0.30), p<0.003] in the HRT-plus-calcitriol treated patients, resulting in alpha being significantly higher after 8 months in the latter group than in the HRT-only group. Although 72% of the patients had been supplemented with calcium between the first and second studies, separate analyses revealed that the change in calcium intake had not affected the result. Further breakdown of the groups into baseline 'normal' absorbers (alpha greater than or equal to 0.55) and 'malabsorbers' (alpha <0.55) revealed that alpha decreased with HRT treatment only in the normal absorbers, and remained stable in the malabsorbers. Conversely, following HRT plus calcitriol treatment, alpha increased only in the malabsorbers, the normal absorbers in this group remaining unchanged. In conclusion, our data show that HRT, of the type and dose used in this study, did not produce an increase in absorption efficiency; it was in fact associated with a fall. increased absorption efficiency cannot be achieved unless calcitriol is used concurrently, and then only in patients with malabsorption. Calcitriol also had a significant effect in normal absorbers in that it prevented the decline in alpha seen with HRT alone, and thus should be considered in all patients with postmenopausal osteoporosis treated with HRT.
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Background: This study was designed to evaluate serum potassium level variation in a porcine model of hemorrhagic shock ( HS). Methods: Eight pigs were studied in a controlled hemorrhage model of HS. Blood withdrawal began at a 50 mL/min to 70 mL/min rate, adjusted to reach a mean arterial pressure ( MAP) level of 60 mm Hg in 10 minutes. When MAP reached 60 mm Hg, the blood withdrawal rate was adjusted to maintain a MAP decrease rate of 10 mm Hg every 2 minutes to 4 minutes. Arterial and mixed venous blood samples were collected at MAP levels of 60 mm Hg, 50 mm Hg, 40 mm Hg, 30 mm Hg, 20 mm Hg, and 10 mm Hg and analyzed for oxygen saturation, PO(2), PCO(2), potassium, lactate, bicarbonate, hemoglobin, pH, and standard base excess. Results: Significant increase in serum potassium occurred early in all animals. The rate of rise in serum potassium and its levels accompanied the hemodynamic deterioration. Hyperkalemia ( K >5 mmol/L) incidence was 12.5% at 60 mm Hg and 50 mm Hg, 62.5% at 40 mm Hg, 87.5% at 30 mm Hg, and 100% at 20 mm Hg. Strong correlations were found between potassium levels and lactate ( R = 0.82), SvO(2) ( R = 0.87), Delta pH ( R = 0.83), and Delta PCO(2) ( R = 0.82). Conclusions: Serum potassium increase accompanies the onset of HS. The rise in serum potassium was directly related to the hemodynamic deterioration of HS and strongly correlated with markers of tissue hypoxia.
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Background: Different hemodynamic parameters including static indicators of cardiac preload as right ventricular end-diastolic volume index (RVEDVI) and dynamic parameters as pulse pressure variation (PPV) have been used in the decision-making process regarding volume expansion in critically ill patients. The objective of this study was to compare fluid resuscitation guided by either PPV or RVEDVI after experimentally induced hemorrhagic shock. Methods: Twenty-six anesthetized and mechanically ventilated pigs were allocated into control (group I), PPV (group II), or RVEDVI (group III) group. Hemorrhagic shock was induced by blood withdrawal to target mean arterial pressure of 40 mm Hg, maintained for 60 minutes. Parameters were measured at baseline, time of shock, 60 minutes after shock, immediately after resuscitation with hydroxyethyl starch 6% (130/0.4), 1 hour and 2 hours thereafter. The endpoint of fluid resuscitation was determined as the baseline values of PPV and RVEDVI. Statistical analysis of data was based on analysis of variance for repeated measures followed by the Bonferroni test (p < 0.05). Results: Volume and time to resuscitation were higher in group III than in group II (group III = 1,305 +/- 331 mL and group II = 965 +/- 245 mL, p < 0.05; and group III = 24.8 +/- 4.7 minutes and group II = 8.8 +/- 1.3 minutes, p < 0.05, respectively). All static and dynamic parameters and biomarkers of tissue oxygenation were affected by hemorrhagic shock and nearly all parameters were restored after resuscitation in both groups. Conclusion: In the proposed model of hemorrhagic shock, resuscitation to the established endpoints was achieved within a smaller amount of time and with less volume when guided by PPV than when guided by pulmonary artery catheter-derived RVEDVI.