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In response to the global transition to a low-carbon economy, carbon risk reduction in diversified portfolios has become imperative. We develop a new hedge approach to mitigate carbon risk, quantified as the carbon beta using a multi-factor model. By calculating a novel hedge ratio, investors are provided with an optimal allocation to a hedge asset, facilitating the effective reduction of carbon beta within their portfolios. Our findings highlight the effectiveness of this approach, which leads to carbon beta reductions without significant losses in risk-adjusted returns, implying that investors and fund managers can adopt this hedge strategy to moderate their carbon risk exposure. Compared to other carbon risk hedge methods, our approach only requires an investment in one more asset, making real-world applications relatively straightforward. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the development of a 3D formed and metal-based facade element that combines a custom design and solar thermal functionality. To achieve this, a novel simplified solar thermal collector structure was developed using formed sheet metal half-shells with an integrated channel structure on the inside and a special absorber coating on the outside. The sheet metal half-shells were manufactured by highly innovative incremental sheet forming (ISF), which allows seamless integration into existing facades. As a part of this paper, the initial test results on thermal efficiency and the energy accumulation of the new collector type are presented. [ABSTRACT FROM AUTHOR]

The effects of steps on the transition of laminar boundary layers were measured on a flat plate for low Reynolds numbers with critical and subcritical step heights. The transition position was measured by determining the intermittency distribution in streamwise direction, including the characteristic length of the transitional region. The results are compared with formulations of a critical step Reynolds number Re h , i.e., the step height that will instantly trigger transition at the step position, and—for subcritical step heights—with Δ N -formulations from the literature. For backward-facing steps, the concept of a step Reynolds number can be used to distinguish between subcritical and critical step heights, whereas for forward-facing steps there seems not to be one unique Re h . Furthermore, for subcritical backward-facing steps the concept of a Δ N -approximation gives a reasonable description of the experimental observations. Again in contrast, for forward-facing steps a Δ N -approach scattered a lot and no clear dependency was found between the reduction in the critical N-factor of transition and the relative step height. [ABSTRACT FROM AUTHOR]

Copyright of Historische Zeitschrift is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We discuss a method to quantify the supersonic discharge of airbag cold gas inflators. Since one primary quantity of interest, the mass flow with time, is not directly measurable, a combined experimental and numerical approach was chosen. Shadowgraph and schlieren images visualize the gas dynamic process. Pressure measurements were conducted inside the inflator and downstream of the outlets in the supersonic jet. In this context, a method to measure the pressure of the flow without effects of shock reflection is presented. The temperature inside the inflator was estimated using a fast response heat flux probe and assuming different scenarios for the unknown heat transfer coefficient. Then, a numerical model of the inflator was created. The experimental results served as boundary conditions and some basic sensitivities remaining unknown from the measurements were studied to verify the numerical outcome. The numerical model was verified using experimental results. Finally, the mass flow rate was derived from the numerical model and compared to an analytical model. The method can reconstruct the temporal evolution of the mass flow discharging from the inflator, the pressure and the topology of the flow field within acceptable bounds. Furthermore, the method can deliver inflow data for subsequent airbag inflation studies. [ABSTRACT FROM AUTHOR]

Background: The objective of the STREAM Trial was to evaluate the effect of simulation training on process times in acute stroke care. Methods: The multicenter prospective interventional STREAM Trial was conducted between 10/2017 and 04/2019 at seven tertiary care neurocenters in Germany with a pre‐ and post‐interventional observation phase. We recorded patient characteristics, acute stroke care process times, stroke team composition and simulation experience for consecutive direct‐to‐center patients receiving intravenous thrombolysis (IVT) and/or endovascular therapy (EVT). The intervention consisted of a composite intervention centered around stroke‐specific in situ simulation training. Primary outcome measure was the 'door‐to‐needle' time (DTN) for IVT. Secondary outcome measures included process times of EVT and measures taken to streamline the pre‐existing treatment algorithm. Results: The effect of the STREAM intervention on the process times of all acute stroke operations was neutral. However, secondary analyses showed a DTN reduction of 5 min from 38 min pre‐intervention (interquartile range [IQR] 25–43 min) to 33 min (IQR 23–39 min, p = 0.03) post‐intervention achieved by simulation‐experienced stroke teams. Concerning EVT, we found significantly shorter door‐to‐groin times in patients who were treated by teams with simulation experience as compared to simulation‐naive teams in the post‐interventional phase (−21 min, simulation‐naive: 95 min, IQR 69–111 vs. simulation‐experienced: 74 min, IQR 51–92, p = 0.04). Conclusion: An intervention combining workflow refinement and simulation‐based stroke team training has the potential to improve process times in acute stroke care. [ABSTRACT FROM AUTHOR]

Copyright of Chemie in unserer Zeit is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The liquidity regulation of banks in Pillar 1 of the Basel framework does not consider longer-term funding cost risks of different bank business models. Therefore, we assemble a data set of balance sheet positions including maturities and use the method of Value-Liquidity-at-Risk to explore 118 European retail, wholesale, and trading banks. When examining liquidity-induced equity risks, trigged by exemplary rating shifts, we find that retail banks bear significantly lower funding cost risks than wholesale and trading banks. Consequently, a prudential regulation, which simultaneously considers the funding cost risk and the diversification of the banking system, is recommended. [ABSTRACT FROM AUTHOR]

In this contribution a method is presented which allows for the characterization of the magnetic (μ'-jμ") as well as the dielectric (ε'-jε") properties of ferrites in a broad frequency band (kHz to GHz). In order to determine the material properties at certain frequencies, the simulation model parameters of a particular test setup are tuned via optimization such that the simulated response of a sample to an electromagnetic excitation matches to the measured one. A loop and parallel plate setup support a low frequency parameter extraction of the sample while a coplanar line is used for high frequencies. The extracted material properties are fitted by a broadband causal fit in order to obtain a material model for the whole frequency range. The presented method is verified for a setup with a coil and a ferrite core. The results show that dielectric properties of the ferrite core cannot be neglected for microwave frequencies. [ABSTRACT FROM AUTHOR]

In this paper, a quasi-static formulation of the PEEC-method including inductive and capacitive effects is coupled with a surface magnetization formulation allowing for modeling linear magnetic materials in combination with arbitrary conductor arrangements. Special care is taken to give a systematic derivation of the underlying equations, an adaptive mesh algorithm for the surface mesh of the magnetic materials, and a multifunction implementation for a mixed domain concerning orthogonal and nonorthogonal cells. The approach is verified with examples according to the finite-element method and measurements. [ABSTRACT FROM AUTHOR]

The two most important measurement categories in production are temperature and load. Therefore commercial sensors are applied in machinery as near as possible to the working parts. For a cost efficient production the integration of sensor elements directly on top of the surface in the heavily loaded regions is essential to get the real temperature and load distributions during the production process. Therefore a new multifunctional thin film sensor system is in development. This multilayer system combines thermoresistive sensor structures with piezoresistive ones and exists out of wear resistant carbon based layers (Bewilogua and Hofmann, Surf Coat Technol 242:214-225, 2014; Biehl et al. Thin Solid Films 515:1171-1175, 2006; Biehl et al. Microsystem Technologies, Springer, 2010; Biehl et al. Microsystem Technologies, Springer, 2014; Robertson, Daim Relat Mater 12:79-84, 2003). The sensor data will lead to a deeper process understanding, to optimization of simulation tools, to reduction of rejects and to an improvement of flexibility in production. [ABSTRACT FROM AUTHOR]

Femoral cannulation during cardiopulmonary bypass has become a common approach for many cardiac procedures and serves as an important access option, especially during minimally invasive cardiac surgery. Opponents, however, argue that there is significant risk, including site-specific and overall morbidity, which makes the use of this modality dangerous compared to conventional aortoatrial cannulation techniques. We analyzed our institutional experience to elucidate the safety and efficacy of femoral cannulation. All data were collected from a single hospital’s cardiac surgery database. A total of 346 cardiac surgeries were evaluated from September 2012 to September 2013, of which 85/346 (24.6%) utilized a minimally invasive approach. Of the 346 operations performed, 72/346 (20.8%) utilized femoral cannulation while 274/346 (79.2%) used aortoatrial cannulation. Stroke occurred in 1/72 (1.39%) after femoral cannulation, specifically, in a conventional sternotomy patient, while it occurred in 6/274 (2.19%) [p=0.67] after aortoatrial cannulation. When comparing postoperative complications between the femoral cannulation and aortoatrial cannulation groups, the rates of atrial fibrillation [10/72 (13.9%) versus 46/274 (16.8%), p=0.55], renal failure [2/72 (2.78%) versus 11/274 (4.01%), p=0.62], prolonged ventilation time [4/72 (5.56%) versus 27/274 (9.85%), p=0.26] and re-operation for bleeding [3/72 (4.17%) versus 13/274 (4.74%), p=0.84] showed no significant difference. Selective femoral cannulation provides a safe alternative to aortoatrial cannulation for cardiopulmonary bypass and is especially important when performing minimally invasive cardiac surgery. When comparing aortoatrial and femoral cannulation, we found no significant difference in the postoperative complication rates and overall mortality. [ABSTRACT FROM AUTHOR]

The flow in a high aspect ratio generic cooling duct is described for different Reynolds numbers and for adiabatic as well as non-adiabatic conditions. The Reynolds number is varied in a range from 39,000 to 111,000. The generic cooling duct facility allows for applying a constant temperature on the duct's lower wall, and it ensures having well-defined boundary conditions. The high-quality, optical noninvasive measurement methods, namely Particle Image Velocimetry (2C2D-PIV, i.e., two velocity components in a plane), Stereo Particle Image Velocimetry (3C2D-PIV, i.e., three velocity components in a plane) and Volumetric Particle Tracking Velocimetry (3C3D-PTV, i.e., three velocity components in a volume), are used to characterize the flow in detail. Pressure transducers are installed for measuring the pressure losses. The repeatability and the validity of the data are discussed in detail. For that purpose, modifications in the test facility and in the experimental setup as well as comparisons between the different measurement methods are given. A focus lies on the average velocity distribution and on the turbulent statistics. The longitudinal velocity profile is analyzed in detail for Reynolds number variations. Secondary flows are identified with velocities of two orders of magnitude smaller than the longitudinal velocity. Reynolds stress distributions are given for several different cases. The Reynolds number dependency of $$\overline{u'^2}$$ and $$\overline{v'^2}$$ is shown, and a comparison between the adiabatic and the heated case is given. $$\overline{u'^2}$$ changes significantly when the lower wall heat flux is applied, whereas $$\overline{v'^2}$$ and $$\overline{u'v'}$$ almost stay constant. [ABSTRACT FROM AUTHOR]

This paper focuses on two special aspects regarding fast partial inductance computations in the nonorthogonal partial element equivalent circuit (PEEC) method. First, a multifunction PEEC algorithm is proposed, which is able to calculate partial inductances as efficient as possible for mixed environments with nonorthogonal as well as orthogonal cells. Second, a new numerical integration routine for the self-inductance terms of nonorthogonal cells is focused on by using averaged orthogonal subelements. It is presented that the slow convergence caused by the singularities is avoided and a fast evaluation of the self-terms is enabled consequently. The approach is verified by two examples where a good agreement is obtained when comparing the proposed results with analytical solutions as well as finite-element method reference results. [ABSTRACT FROM AUTHOR]

Motivation: Co-regulated genes are not identified in traditional microarray analyses, but may theoretically be closely functionally linked [guilt-by-association (GBA), guilt-by-profiling]. Thus, bioinformatics procedures for guilt-by-profiling/association analysis have yet to be applied to large-scale cancer biology.We analyzed 2158 full cancer transcriptomes from 163 diverse cancer entities in regard of their similarity of gene expression, using Pearson’s correlation coefficient (CC). Subsequently, 428 highly co-regulated genes (|CC| ≥ 0.8) were clustered unsupervised to obtain small co-regulated networks. A major subnetwork containing 61 closely co-regulated genes showed highly significant enrichment of cancer bio-functions. All genes except kinesin family member 18B (KIF18B) and cell division cycle associated 3 (CDCA3) were of confirmed relevance for tumor biology. Therefore, we independently analyzed their differential regulation in multiple tumors and found severe deregulation in liver, breast, lung, ovarian and kidney cancers, thus proving our GBA hypothesis. Overexpression of KIF18B and CDCA3 in hepatoma cells and subsequent microarray analysis revealed significant deregulation of central cell cycle regulatory genes. Consistently, RT-PCR and proliferation assay confirmed the role of both genes in cell cycle progression.Finally, the prognostic significance of the identified KIF18B- and CDCA3-dependent predictors (P = 0.01, P = 0.04) was demonstrated in three independent HCC cohorts and several other tumors.In summary, we proved the efficacy of large-scale guilt-by-profiling/association strategies in oncology. We identified two novel oncogenes and functionally characterized them. The strong prognostic importance of downstream predictors for HCC and many other tumors indicates the clinical relevance of our findings.Contact: andreas.teufel@ukr.deSupplementary information: Supplementary data are available at Bioinformatics online. [ABSTRACT FROM AUTHOR]

Copyright of Chemie in unserer Zeit is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The generation, insertion, pressurization and use of oil-based tracer particles is qualified for the application in heated flow facilities, typically hypersonic facilities such as Ludwieg tubes. The operative challenges are to ensure a sub-critical amount of seeding material in the heated part, to qualify the methods that are used to generate the seeding, pressurize it to storage tube pressure, as well as to test specific oil types. The mass of the seeding material is held below the lower explosion limit such that operation is safe. The basis for the tracers is qualified in off-situ particle size measurements. In the main part different methods and operational procedures are tested with respect to their ability to generate a suitable amount of seeding in the test section. For the best method the relaxation time of the tracers is qualified by the oblique shock wave test. The results show that the use of a special temperature resistant lubricant oil 'Plantfluid' is feasible under the conditions of a Mach-6 Ludwieg tube with heated storage tube. The method gives high-quality tracers with high seeding densities. Although the experimental results of the oblique shock wave test differ from theoretical predictions of relaxation time, still the relaxation time of 3.2 μs under the more dense tunnel conditions with 18 bar storage tube pressure is low enough to allow the use of the seeding for meaningful particle image velocimetry studies. [ABSTRACT FROM AUTHOR]

The global wall shear stress measurement technique using shear-sensitive liquid crystal (SSLC) is extended to wind tunnel measurements. Simple and common everyday equipment is used in the measurement; in particular a tungsten-halogen light bulb provides illumination and a saturation of SSLC coating color change with time is found. Spatial wall shear stress distributions of several typical flows are obtained using this technique, including wall-jet flow, vortex flow generated by a delta wing and junction flow behind a thin cylinder, although the magnitudes are not fully calibrated. The results demonstrate that SSLC technique can be extended to wind tunnel measurements with no complicated facilities used. [ABSTRACT FROM AUTHOR]

Experiments are conducted to evaluate the ability of various schemes to correct for pressure distortion caused by a finite tubing length between the pressure tap and the transducer. This study focuses on relatively short tubes, such as those encountered in multi-hole probes. Experimentally determined dynamic response is compared to the analytical model of Berg and Tijdeman with and without the Wiener filter. Bench-top experiments show that, for pneumatic systems with relatively short tubes, the addition of the Wiener filter carries no advantage over the Berg and Tijdeman model. The true advantage of the Wiener deconvolution method is observed for pressure tubes longer than ∼150 mm. Finally, the mean axial velocity and three Reynolds stress distributions from three correction schemes are compared to particle image velocimetry (PIV) results in a shear flow experiment. The statistical results ascertain the advantage of the Berg and Tijdeman and the Wiener deconvolution method over the generally noise-dominated inverse transfer function method. [ABSTRACT FROM AUTHOR]

Radiation protection is a topic of great public concern and of many scientific investigations, because ionizing radiation is an established risk factor for leukaemia and many solid tumours. Exposure of the public to ionizing radiation includes exposure to background radiation, as well as medical and occupational exposures. A large fraction of the exposure from diagnostic procedures comes from medical imaging. Computed tomography (CT) is the major single contributor of diagnostic radiation exposure. An increase in the use of CTs has been reported over the last decades in many countries. Children have smaller bodies and lower shielding capacities, factors that affect the individual organ doses due to medical imaging. Several risk models have been applied to estimate the cancer burden caused by ionizing radiation from CT. All models predict higher risks for cancer among children exposed to CT as compared to adults. However, the cancer risk associated with CT has not been assessed directly in epidemiological studies. Here, plans are described to conduct an historical cohort study to investigate the cancer incidence in paediatric patients exposed to CT before the age of 15 in Germany. Patients will be recruited from radiology departments of several hospitals. Their individual exposure will be recorded, and time-dependent cumulative organ doses will be calculated. Follow-up for cancer incidence via the German Childhood Cancer Registry will allow computation of standardized incidence ratios using population-based incidence rates for childhood cancer. Dose-response modelling and analyses for subgroups of children based on the indication for and the result of the CT will be performed. [ABSTRACT FROM AUTHOR]

A previously determined surface shear stress measurement technique using shear-sensitive liquid crystal (SSLC) coating is extended for use in wind tunnel-like conditions. Simple and common everyday equipment is used in the measurement; in particular a tungsten halogen light bulb provides illumination. The color change characteristics of two SSLC mixtures, BCN192 and BN/R50C, are investigated. BCN/192 is found sensitive to both magnitude and direction of the shear stress at different shear stress levels with little noise, and is suitable for surface shear stress distribution measurements. The spatial shear stress vector distribution beneath a tangential jet is obtained using BCN/192, although the magnitude is not fully calibrated. BN/R50C is found to be sensitive to shear stress magnitude, but only slightly sensitive to shear stress direction at both low and high levels. Moreover, jumps in the reflected hue are found when the viewing orientation is perpendicular to the shear stress direction. These characteristics render the use of BN/R50C for surface shear stress measurement difficult. [ABSTRACT FROM AUTHOR]

Shear sensitive liquid crystal coating (SSLCC) can measure surface shear stress vector distribution efficiently with a high spatial resolution. The purpose of the present paper is to modify and extend the surface shear stress measurement technique determined by Reda et al. to wind tunnel studies. All the facilities employed in the technique are very common and simple. The measurement technique is applied to surface flow beneath a tangential jet and surface flow in a turbulence wedge generated by a small cylinder in windtunnel flow. Spatially resolved shear stresses over planar surface are obtained, although the magnitude is not fully calibrated. [ABSTRACT FROM AUTHOR]

In this paper equivalent circuit models of inductive coupled radio frequency identification (RFID) antenna systems are extracted by means of the partial element equivalent circuit (PEEC) method. Each antenna impedance is analyzed separately regarding frequency dependent behavior including skin- and proximity effects as well as parasitic capacitances. On the contrary, the inductive coupling between any two coils is computed for an arbitrary 3D spatial arrangement by a filamentary mutual inductance computation technique, allowing for fast spatial sweeps. Both models are combined to a reduced equivalent circuit that maintains the topology of mutually coupled inductances. The described approach is tested with a conventional reader transponder arrangement and compared with the full PEEC models. [ABSTRACT FROM AUTHOR]

1. In the present study, we tested hypothesis that upregulation of hypoxia-inducible factor-1 (HIF-1) would improve the actions of positive inotropic agents in cardiac myocytes after simulated ischaemia–reperfusion (I/R). 2. Hypoxia-inducible factor-1α was upregulated with deferoxamine (150 mg/kg per day for 2 days). Rabbit cardiac myocytes were subjected to simulated ischaemia (15 min, 95% N2–5% CO2) and reperfusion (re-oxygenation) and compared with control myocytes. Cell contraction and calcium transients were measured at baseline and after forskolin (10−7 and 10−6 mol/L) or ouabain (10−5 and 10−4 mol/L). 3. Under control conditions, high-dose forskolin and ouabain increased percentage shortening by 20 and 18%, respectively. Deferoxamine-treated control myocytes responded similarly. In stunned myocytes, forskolin and ouabain did not significantly increase shortening (increases of 8% and 9%, respectively). Deferoxamine restored the effects of forskolin (+26%) and ouabain (+28%) in stunning. The results for maximum shortening and relaxation rates were similar. The increased calcium transients caused by forskolin and ouabain were also depressed in stunned myocytes, but were maintained by HIF-1 upregulation. 4. These results suggest that simulated I/R impaired the functional and calcium transient effects of positive inotropic agents. Upregulation of HIF-1 protects cardiac myocyte function after I/R by maintaining calcium release. [ABSTRACT FROM AUTHOR]

The California Department of Health Services' Occupational Health Branch and others have identified the construction industry as being at high risk for injuries, illnesses, and fatalities. Effective tailgate trainings (brief job site safety meetings) can be a powerful tool to promote hazard awareness and safe work practices. The authors found that many contractors and supervisors conducted ineffective tailgate trainings. They developed the BuildSafe California Project to assist contractors to have more effective programs by holding 25 training-of-trainers sessions reaching 1,525 participants. The needs assessment, intervention, and evaluation results from the first 18 trainings are presented. Eighty-six percent of the participants found the program "very helpful." Participants used the materials and made improvements in the quality and frequency of trainings. Supervisors must be skilled at conducting tailgate trainings as part of their responsibilities. There is a serious need to provide more culturally appropriate safety training in a workforce increasingly made up of Latino workers. [ABSTRACT FROM AUTHOR]

The negative functional effects of cyclic GMP are controlled by the sarcoplasmic reticulum calcium-ATPase (SERCA). The effects of cyclic GMP are blunted in cardiac hypertrophy. We tested the hypothesis that the interaction between cyclic GMP and SERCA would be reduced in hypertrophic cardiac myocytes. Myocytes were isolated from 7 control and 7 renal-hypertensive hypertrophic rabbits. Control and hypertrophic myocytes received 8-bromo-cGMP (8-Br-cGMP; 10–7, 10–6, 10–5 mol/l), the SERCA blocker thapsigargin (10–8 mol/l) followed by 8-Br-cGMP, or the SERCA blocker, cyclopiazonic acid (CPA; 10–7 mol/l) followed by 8-Br-cGMP. Percent shortening and maximal rate of shortening and relaxation were recorded using a video edge detector. Changes in cytosolic Ca2+ were assessed in fura 2-loaded myocytes. In controls, 8-Br-cGMP caused a significant 36% decrease in percent shortening from 5.8 ± 0.4 to 3.7 ± 0.3%. Thapsigargin and CPA did not affect basal control or hypertrophic myocyte function. When 8-Br-cGMP was given following thapsigargin or CPA, the negative effects of 8-Br-cGMP on control myocyte function were reduced. In hypertrophic myocytes, 8-Br-cGMP caused a smaller but significant 17% decrease in percent shortening from 4.7 ± 0.2 to 3.9 ± 0.1%. When 8-Br-cGMP was given following thapsigargin or CPA, no significant changes occurred in hypertrophic cell function. Intracellular Ca2+ transients responded in a similar manner to changes in cell function in control and hypertrophic myocytes. These results show that the effects of cyclic GMP were reduced in hypertrophic myocytes, but this was not related to SERCA. In presence of SERCA inhibitors, the responses to cyclic GMP were blunted in hypertrophic as well as control myocytes. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The paper presents research on increasing the efficiency of industrial centrifugal fans, which are the third highest energy-consuming group of devices. This problem is related to the frequent incompatibility of the fan characteristics with the flow conditions of the installation in which they are operated, which lowers efficiency and increases energy consumption. By ensuring high efficiency of these devices, it is possible to significantly reduce the operating costs of such industrial equipment. For this purpose, a unique concept of regulating the flow parameters of centrifugal fans was developed. The scientific basis of this idea is that a relatively small change in the impeller diameter of the fan significantly affects the flow rate and the pressure rise of the fan. Therefore, the idea uses variable length of the impeller blades by dividing them into a fixed and a movable part. It enables adjustment of the length of the blades, which allows extension of the range of effective and efficient operating parameters. On this basis, several technical solutions of the regulation system were developed, which were then tested using simulation and analytical methods. Two material options for the moving part of the blade have also been developed, one made of metallic materials (high-strength steel and aluminum) and the other made of composite materials. The research showed a significant influence of the mass of the movable part of the blade on the load of the control system. Therefore, ultra-light material variants were used for the impeller blades. The flow simulation tests of the new method of adjusting the fan flow parameters confirmed the effectiveness of this solution. As a result, a wider range of highly efficient centrifugal fans equipped with such a control system was obtained. [ABSTRACT FROM AUTHOR]

Ischemia-reperfusion reduces the negative functional effects of cyclic GMP in cardiac myocytes. In this study, we tested the hypothesis that upregulation of hypoxic inducible factor-1 (HIF-1) would improve the actions of cyclic GMP signaling following simulated ischemia-reperfusion. HIF-1α was increased with deferoxamine (150 mg/kg for 2 days). Rabbit cardiac myocytes were subjected to simulated ischemia [15 min 95% N2-5% CO2] and reperfusion [reoxygenation] to produce myocyte stunning. Cell function was measured utilizing a video-edge detector. Shortening was examined at baseline and after brain natriuretic peptide (BNP, 10-8, 10-7M) or S-nitroso-N-acetyl-penicillamine (SNAP, 10-6, 10-5M) followed by KT5823 (cyclic GMP protein kinase inhibitor, 10-6M). Kinase activity was measured via a protein phosphorylation assay. Under control conditions, BNP (-30%) and SNAP (-41%) reduced percent shortening, while KT5823 partially restored function (+18%). Deferoxamine treated control myocytes responded similarly. In stunned myocytes, BNP (-21%) and SNAP (-25%) reduced shortening less and KT5823 did not increase function (+2%). Deferoxamine increased the effects of BNP (-38%) and SNAP (-41%) in stunning and restored the effects of KT5823 (+12%). The cyclic GMP protein kinase increased phosphorylation of several proteins in control HIF-1 +/- cells. Phosphorylation was reduced in stunned cells and was restored in deferoxamine treated stunned cells. This study demonstrated that simulated ischemia-reperfusion reduced the negative functional effects of increasing cyclic GMP and this was related to reduced effects of the cyclic GMP protein kinase. Increased HIF-1α protects the functional effects of cyclic GMP thorough maintenance of cyclic GMP protein kinase activity after ischemic-reperfusion. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We tested the hypothesis that the negative functional effects of cyclic GMP on cardiac myocytes were mediated through phospholamban (PLB) and activation of sarcoplasmic reticulum Ca2+-ATPase. Using ventricular myocytes from wild type (WT, n=10) and PLB knockout (PLB-KO, n=10) mouse hearts, functional changes were measured using a video edge detector at baseline and after 10-6, 10-5M 8-bromo-cyclic GMP (cGMP), 10-8, 10-7M C-type natriuretic peptide (CNP), or 10-6, 10-5M S-nitroso-N-acetyl-penicillamine (SNAP, nitric oxide donor). Changes in cytosolic Ca2+ concentration were assessed in fura 2-loaded WT and PLB-KO myocytes. Cyclic GMP dependent phosphorylation analysis was also performed in WT and PLB-KO myocytes. 8-bromo-cGMP 10-5M caused a significant decrease in %shortening (3.6±0.2% to 2.3±0.1%) in WT, but little change in PLB-KO myocytes (3.4±0.1% to 3.2±0.2%). Similarly, CNP and SNAP reduced %shortening of WT, but not PLB-KO myocyte. Changes in other contractile parameters such as maximum rate of shortening and relaxation were consistent with the changes in % shortening. Intracellular Ca2+ transients changed similarly to cell contractility in WT and PLB-KO myocytes treated with cGMP and CNP; i.e. Ca2+ transients decreased with cGMP or CNP in WT myocytes, but were unchanged in PLB-KO myocytes. cGMP dependent phosphorylation analysis showed that some proteins were phosphorylated by cGMP to a lesser extent in PLB-KO compared with WT myocytes, suggesting impaired cGMP-kinase function in PLB-KO cardiac myocytes. These results indicated that cGMP-induced reductions in cardiac myocyte function were at least partially mediated through the action of phospholamban. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

We tested the hypothesis that brain natriuretic peptide (BNP) would decrease the effects of myocardial stunning in rabbit hearts. We also examined the mechanisms responsible for these effects. In two groups of anesthetized open-chest rabbits, myocardial stunning was produced by 2 15-min occlusions of the left anterior descending artery separated by 15 min of reperfusion. The treatment group had BNP (10–3 mol/l) topically applied to the stunned area. Hemodynamic and functional parameters were measured. Coronary flow and O2 extraction were used to determine myocardial O2 consumption. In separate animals, we measured the function of isolated control and simulated ischemia (95% N2/5% CO2, 15 min)-reperfusion ventricular myocytes with BNP or C-type natriuretic peptide (10–8–10–7 mol/l) followed by KT5823 (10–6 mol/l, cyclic GMP protein kinase inhibitor). In the in vivo control group, baseline delay to contraction was 47 ± 4 ms and after stunning it increased to 71 ± 10 ms. In the treatment group, baseline delay to contraction was 40 ± 7 ms, and after stunning and BNP it did not significantly increase (43 ± 6 ms). Neither stunning nor BNP administration affected regional O2 consumption. In control myocytes, BNP (10–7 mol/l) decreased the percent shortening from 6.7 ± 0.4 to 4.5 ± 0.2%; after KT5823 administration, the percent shortening increased to 5.4 ± 0.5%. In ischemia-reperfusion myocytes, BNP (10–7 mol/l) decreased the percent shortening less from 5.0 ± 0.5 to 3.8 ± 0.2%; KT5823 administration did not increase the percent shortening (3.8 ± 0.2%). BNP similarly and significantly increased cyclic GMP levels in control and stunned myocytes. The data illustrated that BNP administration reversed the effects of stunning and its mechanism may be independent of the cyclic GMP protein kinase. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In this contribution, it is shown that perfect synchroneous specifications can be partitioned to and implemented on a distributed processor network. To this end, we introduce a lean visual formalism, called μ-charts, that is similar to the specification language Statecharts. This formalism consists of fewer syntactic constructs than Statecharts. Further syntax like hierarchical decomposition can be derived by means of syntactic abbreviation. μ-charts' semantics is based on the assumption of perfect synchrony. This paper is one of several contributions in this context; it gives a formal background and concentrates on the question how to use perfect synchroneous, state-based description techniques as a basis for distributed implementations. The main contribution presented in this article is that the (formal and compositional) semantics of a perfect synchroneous specification is preserved when it is partitioned and implemented on distributed processors. We prove a theorem which guarantees that the communication flow between distributed parts of a perfect synchroneous specification stabilizes in a fixed point, i.e.$ terminates, independently of the processor speeds. [ABSTRACT FROM AUTHOR]

This study tested the hypothesis that the positive inotropic effect of β-adrenoceptor stimulation would be inhibited by increases in cyclic GMP in control cardiomyocytes and that this response would be modified in hypertrophic cardiomyocytes. Cell functional data as well as GMP and cyclic AMP data were collected from 7 control and 7 1K1C (one-kidney-one-clip) renal hypertensive hypertrophic rabbits. Using isolated control and IKIC ventricular myocytes, data were obtained at baseline and after treatment with the β-adrenoceptor agonist isoproterenol (10-8, -6 mol/l) or the cyclic GMP-phosphodiesterase inhibitor zaprinast (10-5 mol/l) followed by isoproterenol(10-8,-6' mol/l). We found that in control rabbits, isoproterenol (10-6 mol/l) increased percent shortening (4.8 ± 0.2 to 6.4 ± 0.3%) and cyclic AMP (2.3 ± 0.3 to 5.0 ± 0.7 pmol/105 cells). Zaprinast 10-5 mol/l increased cyclic GMP (150 ± 20 to 209 ± 14 fmol/105 cells) and decreased percent shortening (6.2 ± 0.4 to 5.2 ± 0.3). Zaprinast 10-5 mol/l prevented the functional response to isoproterenol in control (5.2 ± 0.3 to 4.7 ± 0.3), without changing cyclic AMP levels. In 1K1C rabbits, isoproterenol (10-6 mol/l) increased cyclic AMP (4.9 ± 0.8 to 7.6 ± 1.4 pmol/105 cells) without changing function. Zaprinast 10-5 mol/l increased cyclic GMP (182 ± 23 to 233 ± 24 fmol/105 cells) and decreased percent shortening (6.6 ± 0.9 to 4.7 ± 0.5), but did not alter the lack of effect of isoproterenol in 1K1C. In control cardiomyocytes, cyclic GMP blunted the isoproterenol contraction response without changing cyclic AMP levels, but isoproterenol's functional effect was not seen in 1K1C cardiomyocytes. [ABSTRACT FROM AUTHOR]