Measurements of emissions for lpg combustion within a porous cylindrical burners

CO and NO[x] emission characteristics of a hollow cylindrical radiation burner operated in the external and internal combustion modes and premixed LPG+air mixtures are experimentally studies. The influence of the pore structure, equivalence ratio, firing rate and burner design are considered

The Road to a Top Ranking A Complexity-Oriented View on the Development of Countries:The Netherlands, Singapore, and Switzerland compared

The Netherlands, Singapore, and Switzerland have long been high in international rankings of prosperity and well-being. Other countries struggle to achieve success, and some even fall into decline. This research project examines how countries rise to the top and remain in an ever-changing world. What gives them the energy and makes them adaptive? What role do governments play in this? What can administrators do to keep their countries energized and adaptive, from government leaders to members of parliament? When selecting countries, similarities in size and institutional-organizational differences were important criteria. In Singapore, central control prevails, while decentralized self-organization is characteristic in Switzerland. In the Netherlands, there is a mix of both systems. The research reveals that variations in applying these guiding principles are not decisive in achieving top positions. The distinction lies in the interaction between the network architecture, the initial conditions of a country system, and the organization of energy management in the three countries.<br/

The Road to a Top Ranking A Complexity-Oriented View on the Development of Countries:The Netherlands, Singapore, and Switzerland compared

The Netherlands, Singapore, and Switzerland have long been high in international rankings of prosperity and well-being. Other countries struggle to achieve success, and some even fall into decline. This research project examines how countries rise to the top and remain in an ever-changing world. What gives them the energy and makes them adaptive? What role do governments play in this? What can administrators do to keep their countries energized and adaptive, from government leaders to members of parliament? When selecting countries, similarities in size and institutional-organizational differences were important criteria. In Singapore, central control prevails, while decentralized self-organization is characteristic in Switzerland. In the Netherlands, there is a mix of both systems. The research reveals that variations in applying these guiding principles are not decisive in achieving top positions. The distinction lies in the interaction between the network architecture, the initial conditions of a country system, and the organization of energy management in the three countries.<br/

A Lagrangian framework for detecting and characterizing the descent of foehn from Alpine to local scales

When foehn winds surmount the Alps from the south, they often abruptly and vigorously descend into the leeside valleys on the Alpine north side. Scientists have long been intrigued by the underlying cause of this pronounced descent. While mountain gravity waves and the hydraulic theory provide theoretical foundations to explain the phenomenon, the descent of the Alpine south foehn has, so far, not been explicitly quantified and characterized for a series of real-case events. To fill this research gap, the present study employs kilometer-scale numerical simulations, combined with online trajectories calculated during model integration. In an innovative approach, we adopt the Lagrangian perspective, enabling us to identify the descent and determine its key characteristics across foehn regions spanning from the Western to the Eastern Alps. In the first part of the study, we find the descent of foehn air parcels to be primarily confined to distinct hotspots in the immediate lee of local mountain peaks and chains, underlining the fundamental role of local topography in providing a natural anchor for the descent during south foehn. Consequently, the small-scale elevation differences in the underlying terrain are clearly linked to the magnitude of the descent, whereby other contributing factors also influence the process. Combined with the fact that the descent is mostly dry adiabatic, these results suggest that the descending motion occurs along downward-sloping isentropes associated with gravity waves. A small proportion of air parcels experience diabatic cooling and moisture uptake during the descent, which predominantly occur to the south of the Alpine crest. The second part of the study aims to elucidate the different factors affecting the descent on a local scale. To this end, a particularly prominent hotspot situated along the Rätikon, a regional mountain range adjacent to the Rhine Valley, is examined in two detailed case studies. During periods characterized by intensified descent, local peaks along the Rätikon excite gravity waves that are linked to the descent of air parcels into the northern tributaries of the Rätikon and into the Rhine Valley. The two case studies reveal that different wave regimes, including vertically propagating waves, breaking waves, and horizontally propagating lee waves, coincide with the descent. This suggests the absence of a specific wave regime that is consistently present during foehn descent periods along the Rätikon. In addition to gravity waves, other effects likewise influence the descent activity. For example, a topographic concavity deflects the near-surface flow and thus promotes strong descent of air parcels towards the floor of the Rhine Valley. In addition, in one of our cases, nocturnal cooling introduces a smooth virtual topography that inhibits the formation of pronounced gravity waves and impedes the descent of foehn air parcels into the valley atmosphere. In summary, this study approaches a long-standing topic in foehn research from a new angle. Given the limitations of our model simulations, we did not attempt to unequivocally resolve the causes for the descent. Nevertheless, using online trajectories, we explicitly identified and characterized the descent of foehn. The innovative Lagrangian method enabled us to diagnose descent within a comprehensive dataset, encompassing multiple case studies and a wide range of different foehn regions. The findings highlight the benefits offered by the Lagrangian perspective, which not only complements but also substantially extends the previously predominant Eulerian perspective on the descent of foehn.</p

Does Modern Helicopter Construction Reduce Noise Exposure in Helicopter Rescue Operations?

Background: During helicopter rescue operations the medical personnel are at high risk for hearing damage by noise exposure. There are two important factors to be taken into account: first, the extreme variability, with some days involving no exposure but other days with extreme exposure; second, the extreme noise levels during work outside the helicopter, e.g. during winch operations. The benefit of modern, less noisier constructions and the consequences for noise protection are still unknown. Objectives: We estimated the noise exposure of the personnel for different helicopter types used during rescue operations in the Alps and in other regions of the world with special regard to the advanced types like Eurocopter EC 135 to compare the benefit of modern constructions for noise protection with earlier ones. Methods: The rescue operations over 1 year of four rescue bases in the Alps (Raron and Zermatt in Switzerland; Landeck and Innsbruck in Austria, n = 2731) were analyzed for duration of rescue operations (noise exposure). Noise levels were measured during rescue operations at defined points inside and outside the different aircraft. The setting is according to the European standard (Richtlinie 2003/10/EG Amtsblatt) and to Class 1 DIN/IEC 651. With both data sets the equivalent noise level Leq8h was calculated. For comparison it was assumed that all rescue operations were performed with a specific type of helicopter. Then model calculations for noise exposure by different helicopter types, such as Alouette IIIb, Alouette II ‘Lama', Ecureuil AS350, Bell UH1D, Eurocopter EC135, and others were performed. Results and conclusions: Depending on modern technologies the situation for the personnel has been improved significantly. Nevertheless noise prevention, which includes noise intermissions in spare time, is essential. Medical checks of the crews by occupational medicine (e.g. ‘G20' in Germany) are still mandator

Does Modern Helicopter Construction Reduce Noise Exposure in Helicopter Rescue Operations?

Background: During helicopter rescue operations the medical personnel are at high risk for hearing damage by noise exposure. There are two important factors to be taken into account: first, the extreme variability, with some days involving no exposure but other days with extreme exposure; second, the extreme noise levels during work outside the helicopter, e.g. during winch operations. The benefit of modern, less noisier constructions and the consequences for noise protection are still unknown. Objectives: We estimated the noise exposure of the personnel for different helicopter types used during rescue operations in the Alps and in other regions of the world with special regard to the advanced types like Eurocopter EC 135 to compare the benefit of modern constructions for noise protection with earlier ones. Methods: The rescue operations over 1 year of four rescue bases in the Alps (Raron and Zermatt in Switzerland; Landeck and Innsbruck in Austria, n = 2731) were analyzed for duration of rescue operations (noise exposure). Noise levels were measured during rescue operations at defined points inside and outside the different aircraft. The setting is according to the European standard (Richtlinie 2003/10/EG Amtsblatt) and to Class 1 DIN/IEC 651. With both data sets the equivalent noise level Leq8h was calculated. For comparison it was assumed that all rescue operations were performed with a specific type of helicopter. Then model calculations for noise exposure by different helicopter types, such as Alouette IIIb, Alouette II ‘Lama', Ecureuil AS350, Bell UH1D, Eurocopter EC135, and others were performed. Results and conclusions: Depending on modern technologies the situation for the personnel has been improved significantly. Nevertheless noise prevention, which includes noise intermissions in spare time, is essential. Medical checks of the crews by occupational medicine (e.g. ‘G20' in Germany) are still mandator

Chromatin as a model system for studying the regulation of histone gene expression in mammalian cells : (mRNA, chromosomal proteins, transcription, cell cycle)

Histone gene expression was studied during the cell cycle of continuously dividing HeLa S3 cells and after stimulation of confluent monolayers of WI-38 human diploid fibroblasts to proliferate. The presence of histone mRNA sequences was assayed by hybridization to a 3H-tabeted, single-stranded DNA complementary to histone mRNA molecules. In HeLa S3 cells histone mRNA sequences were found in the nucleus and associated with polyribosomes during S phase but not during G1 phase. Transcripts of S phase chromatin contained histone mRNA sequences, but those of G1 phase chromatin did not. Similarly, in WI-38 cells association of histone mRNA sequences with polyribosomes and transcription of histone mRNA sequences from chromatin parallel DNA replication. Taken together, these results suggest that the regulation of histone gene expression resides, at least in part, at the transcriptional level. However, other results suggest that the coupling of histone gene expression and DNA synthesis is mediated post-transcriptionally. Chromatin reconstitution studies provide evidence that (i) a component of the complex and heterogeneous non histone chromosomal proteins plays a key role in activation or derepression of histone gene transcription during the period of the cell cycle when DNA is replicated, (ii) the chromosomal proteins and/or the DNA sequences involved in the regulation of histone gene expression may be similar in mouse and human and (iii) phosphate groups associated with the S phase non histone chromosomal proteins appear to be functionally involved in the control of histone gene readout.GARY STEIN, WILLIAM PARK, JUDITH THOMSON, ROBERT JANSING,ELIZABETH SHEPHARD, AND SIEGFRIED DETKE, Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, Florida ; JANET STEIN, Department of Immunology and Medical Microbiology, University of Florida, Gainesville, Florida ; LEWIS KLEINSMITH, Division of Biological Sciences, University of Michigan, Ann Arbor, Michigan

Metabolic profiling of HepG2 cells incubated with S(−) and R(+) enantiomers of anti-coagulating drug warfarin

Warfarin is a commonly prescribed oral anticoagulant with narrow therapeutic index. It achieves anti-coagulating effects by interfering with the vitamin K cycle. Warfarin has two enantiomers, S(−) and R(+) and undergoes stereoselective metabolism, with the S(−) enantiomer being more effective. We reported the intracellular metabolic profile in HepG2 cells incubated with S(−) and R(+) warfarin by GCMS. Chemometric method PCA was applied to analyze the individual samples. A total of 80 metabolites which belong to different categories were identified. Two batches of experiments (with and without the presence of vitamin K) were designed. In samples incubated with S(−) and R(+) warfarin, glucuronic acid showed significantly decreased in cells incubated with R(+) warfarin but not in those incubated with S(−) warfarin. It may partially explain the lower bio-activity of R(+) warfarin. And arachidonic acid showed increased in cells incubated with S(−) warfarin but not in those incubated with R(+) warfarin. In addition, a number of small molecules involved in γ-glutamyl cycle displayed ratio variations. Intracellular glutathione detection further validated the results. Taken together, our findings provided molecular evidence on a comprehensive metabolic profile on warfarin-cell interaction which may shed new lights on future improvement of warfarin therapy