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Data Shows (data + shows)
Kinds of Data Shows Selected AbstractsControlling factors of gullying in the Maracujá Catchment, southeastern BrazilEARTH SURFACE PROCESSES AND LANDFORMS, Issue 11 2005L. de A. P. Bacellar Abstract Hundreds of gullies (,voçorocas') of huge dimensions (up to 400,500 m long, 150 m wide and 50 m deep) are very common in the small Maracujá Catchment in southeastern Brazil. These erosional features, which occur with an uneven intensity throughout the area, started due to bad soil management practices at the beginning of European settlement, at the end of the 17th century, and nowadays are still evolving, but at a slower rate. As surface soils are usually very resistant to erosion, the outcrop of the more erodible basement saprolites seems to be an essential condition for their beginning. An analysis of well known erosion controlling factors was performed, aiming to explain the beginning and evolution of these gullies and to understand the reasons for their spatial distribution. Data shows that geology and, mainly, geomorphology are the main controlling factors, since gullies tend to be concentrated in basement rock areas with lower relief (domain 2) of Maracujá Catchment, mainly at the fringes of broad and flat interfluves. At the detailed scale (1:10 000), gullies are more common in amphitheatre-like headwater hollows that frequently represent upper Quaternary gullies (paleogullies), which demonstrate the recurrence of channel erosion. So, gullies occur in areas of thicker saprolites (domain 2), in places with a natural concentration of surface and underground water (hollows). Saprolites of the preserved, non-eroded hollows are usually pressurized (confined aquifer) due to a thick seal of Quaternary clay layer, in a similar configuration to the ones found in hollows of mass movement (mudflow) sites in southeastern Brazil. Therefore, the erosion of the resistant soils by human activities, such as road cuts and trenches (,valos'), or their mobilization by mudflow movements, seem to be likely mechanisms of gullying initiation. Afterwards, gullies evolve by a combination of surface and underground processes, such as wash and tunnel erosion and falls and slumps of gully walls. Copyright © 2005 John Wiley & Sons, Ltd. [source] Study of Energy Transfer and Triplet Exciton Diffusion in Hole-Transporting Host MaterialsADVANCED FUNCTIONAL MATERIALS, Issue 19 2009Chao Wu Abstract A device structure is used in which the hole-transporting layer (HTL) of an OLED is doped with either fluorescent or phosphorescent emitters, that is, anode/HTL-host/hole blocker/electron-transporting layer/cathode. The HTL hosts have higher HOMO energy allowing holes to be transported without being trapped by dopant molecules, avoiding direct recombination on the dopant. The unconventional mismatch of HOMO energies between host and dopant allow for the study of energy transfer in these host/guest systems and triplet exciton diffusion in the HTL-host layers of OLED devices, without the complication of charge trapping at dopants. The host materials examined here are tetraaryl- p- phenylenediamines. Data shows that Förster energy transfer between these hosts and emissive dopant in devices is inefficient. Triplet exciton diffusion in these host materials is closely related to molecular structure and the degree of intermolecular interaction. Host materials that contain naphthyl groups demonstrate longer triplet exciton diffusion lengths than those with phenyl substituents, consistent with DFT calculations and photophysical measurements. [source] What does Monetary Policy Reveal about a Central Bank's Preferences?ECONOMIC NOTES, Issue 3 2003Efrem Castelnuovo The design of monetary policy depends on the targeting strategy adopted by the central bank. This strategy describes a set of policy preferences, which are actually the structural parameters to analyse monetary policy making. Accordingly, we develop a calibration method to estimate a central bank's preferences from the estimates of an optimal Taylor,type rule. The empirical analysis on US data shows that output stabilization has not been an independent argument in the Fed's objective function during the Greenspan's era. This suggests that the output gap has entered the policy rule only as leading indicator for future inflation, therefore being only instrumental (to stabilize inflation) rather than important per se. (J.E.L.: C61, E52, E58). [source] The effects of competition and equal treatment laws on gender wage differentialsECONOMIC POLICY, Issue 50 2007Doris Weichselbaumer SUMMARY International gender wage gaps Discrimination, if it is inefficient, can be eliminated by competition. In most countries, it is also forbidden by law. This paper evaluates the influence of economic and legal factors on the portion of male-female wage differentials that is not explained by other worker characteristics and may be due to discrimination. We use a new international data set of suitable gender wage gap measures, constructed from the results of existing studies. Meta-analysis of the data shows that increased competition and adoption of international conventions concerning equal treatment laws both reduce gender wage gaps, while legislation that prevents women from performing strenuous or dangerous jobs tends to increase it. , Doris Weichselbaumer and Rudolf Winter-Ebmer [source] More power to the European Parliament?ECONOMIC POLICY, Issue 35 2002Abdul G. Noury SUMMARY Many observers have expressed scepticism about granting more power to the European Parliament. The sceptics believe that Members of the European Parliament (MEPs) do not vote in a disciplined way and that they vote more often with their country group than with their European Party. Using a unique database consisting of all roll call votes by each individual MEP between 1989 and 1999 (over 6000 votes by over 1000 different MEPs), we show that the sceptics are wrong. Our data shows clearly that MEPs vote more along party lines than along country lines. Party cohesion is comparable to that of the US Congress and is increasing over time whereas country cohesion is low and declining. In short, politics in the European Parliament generally follows the traditional left,right divide that one finds in all European nations. These findings are valid across issues, even on issues like the structural and cohesion funds where one would expect country rather than party cohesion. In votes where the EP has the most power , those held under the so-called co-decision procedure , MEPs participate more and are more party-cohesive. In our opinion, this unique empirical analysis provides grounds for justifying a generalization of the co-decision procedure. [source] Commentary: A Response to Reckase's Conceptual Framework and Examples for Evaluating Standard Setting MethodsEDUCATIONAL MEASUREMENT: ISSUES AND PRACTICE, Issue 3 2006E. Matthew Schulz A look at real data shows that Reckase's psychometric theory for standard setting is not applicable to bookmark and that his simulations cannot explain actual differences between methods. It is suggested that exclusively test-centered, criterion-referenced approaches are too idealized and that a psychophysics paradigm and a theory of group behavior could be more useful in thinking about the standard setting process. In this view, item mapping methods such as bookmark are reasonable adaptations to fundamental limitations in human judgments of item difficulty. They make item ratings unnecessary and have unique potential for integrating external validity data and student performance data more fully into the standard setting process. [source] Long-range transport of organic chemicals in the environmentENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2009Martin Scheringer Abstract The long-range transport (LRT) of organic chemicals in the environment is reviewed, with particular focus on the role of environmental fate and transport models and the relationship between model results and field data. Results from generic multimedia box models, spatially resolved multimedia box models, and atmospheric transport models are highlighted, including conceptual investigations of cold-trap effect and global fractionation as well as results for particular chemicals, such as hexachlorocyclohexanes, DDT, polychlorinated biphenyls, perfluoroocctanoic acid, and polybrominated diphenyl ethers. Comparison of model results to field data shows that in many cases environmental fate models provide a good description of the distribution dynamics observed in the field, with deviations between measured and modeled concentrations around a factor of five. Sorption to atmospheric aerosols as a key process influencing the LRT of semivolatile organic chemicals (SOCs) is discussed, and the need for more measurements of the aerosol,air partitioning of SOCs and of the reactivity of particle-bound chemicals is pointed out. Key findings from field campaigns measuring legacy persistent organic pollutants (POPs) as well as new POPs are summarized. Finally, the relationship between science and politics in the field of POPs is addressed. Research into the LRT of organic chemicals has always occurred in interaction with political activities aiming to reduce the emissions of POPs. Since the late 1990s, the Stockholm Convention and the Aarhus Protocol on POPs have formed an important political context for research concerning POPs; the implementation of these international treaties creates a demand for ongoing research into the LRT of organic chemicals. [source] A New Spherical Metallacryptate Compound [Na{Cu6(Thr)8(H2O)2(ClO4)4}]·ClO4·5,H2O: Magnetic Properties and DFT CalculationsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2005Sheng-Chang Xiang Abstract The hexanuclear copper(II) complex with threoninato acid has been synthesized. Its structure can be described as an octahedron cage with D2h symmetry in which six copper ions are bound by eight threoninato acids with a [3.11223130] coordination mode and one Na+ cation being captured within the center of the cage. In contrast with other hexanuclear copper compounds containing amino acids, the title compound has a prolate Cu6 octahedron with the longest axial distance and a rectangle equatorial plane, as well as special coordinated perchlorate ions. Compared with classic cryptate, hexanuclear copper(II) compounds with amino acids can be regarded as a new topologic type of spherical macrotricyclic metallacryptates [2,2,2,2] whose cages have a high selectivity for sodium ions. The analysis of magnetic susceptibility data shows that the threoninato compound has a ground state with spin S = 3. The computing coupling constant between the equatorial Cu centers and the axial ones is 4.4 cm,1,calculated by using DFT methods for a model compound. This is close to three known experimental values of 1.39, 0.56 or 0.43 cm,1 for complexes with 4-hydroxy- L -prolinato, L -prolinato or L -threoninato acid as ligands, respectively. The dominant ferromagnetic interactions for these complexes can be essentially attributed to the orthogonality between the magnetic orbitals, dxz or dyz orbitals for the equatorial CuII centers and d orbitals for the axial ones. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] How regulatory focus influences consumer behaviorEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 1 2007Lioba Werth According to Higgins (1997) the theory of regulatory focus says that in terms of both information processing and motivation it makes a difference whether people have a promotion or prevention focus. In this paper, this theory will be applied to the area of consumer psychology. In three experiments we show that consumer's regulatory focus either measured or induced in a given situation influences product evaluations. Study 1 shows that consumers are interested in different product features depending on their focus; whereas in the prevention focus they are more interested in safety-oriented aspects, in the promotion focus they concentrate more on comfort-oriented qualities. In Study 2, a typical prevention product and a typical promotion product are compared with one another and data shows that focus compatible products are evaluated more positively. In Study 3 we demonstrate that advertisments that correspond to the focus of the consumer lead to more positive evaluations of the product than advertisments that are incompatible with the focus of the consumer. Theoretical and practical implications will be discussed. Copyright © 2006 John Wiley & Sons, Ltd. [source] Closed-form thermal stress intensity factors for an internal circumferential crack in a thick-walled cylinderFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 8 2010R. GHAJAR ABSTRACT In this paper the method of weight functions is employed to calculate the stress intensity factors for an internal circumferential crack in a thick-walled cylinder. The pressurized cylinder is also subjected to convection cooling on the inner surface. Finite element method is used to determine an accurate weight function for the crack and a closed-form thermal stress intensity factor with the aid of the weight function method is extracted. The influence of crack parameter and the heat transfer coefficient on the stress intensity factors are determined. Comparison of the results in the special cases with those cited in the literature and the finite element data shows that the results are in very good agreement. [source] BJ46a, a snake venom metalloproteinase inhibitorFEBS JOURNAL, Issue 10 2001Isolation, characterization, cloning, insights into its mechanism of action Fractionation of the serum of the venomous snake Bothrops jararaca with (NH4)2SO4, followed by phenyl-Sepharose and C4 -reversed phase chromatographies, resulted in the isolation of the anti-hemorrhagic factor BJ46a. BJ46a is a potent inhibitor of the SVMPs atrolysin C (class P-I) and jararhagin (P-III) proteolytic activities and B. jararaca venom hemorrhagic activity. The single-chain, acidic (pI 4.55) glycoprotein has a molecular mass of 46 101 atomic mass units determined by MALDI-TOF MS and 79 kDa by gel filtration and dynamic laser light scattering, suggesting a homodimeric structure. mRNA was isolated from the liver of one specimen and transcribed into cDNA. The cDNA pool was amplified by PCR, cloned into a specific vector and used to transform competent cells. Clones containing the complete coding sequence for BJ46a were isolated. The deduced protein sequence was in complete agreement with peptide sequences obtained by Edman degradation. BJ46a is a 322-amino-acid protein containing four putative N-glycosylation sites. It is homologous to the proteinase inhibitor HSF (member of the fetuin family, cystatin superfamily) isolated from the serum of the snake Trimeresurus flavoviridis, having 85% sequence identity. This is the first report of a complete cDNA sequence for an endogenous inhibitor of snake venom metalloproteinases (SVMPs). The sequence reveals that the only proteolytic processing required to obtain the mature protein is the cleavage of the signal peptide. Gel filtration analyses of the inhibitory complexes indicate that inhibition occurs by formation of a noncovalent complex between BJ46a and the proteinases at their metalloproteinase domains. Furthermore, the data shows that the stoichiometry involved in this interaction is of one inhibitor monomer to two enzyme molecules, suggesting an interesting mechanism of metalloproteinase inhibition. [source] Evaluation of RuxWySez Catalyst as a Cathode Electrode in a Polymer Electrolyte Membrane Fuel CellFUEL CELLS, Issue 1 2010K. Suárez-Alcántara Abstract The oxygen reduction reaction (ORR) on RuxWySez is of great importance in the development of a novel cathode electrode in a polymer electrolyte membrane fuel cell (PEMFC) technology. The RuxWySez electrocatalyst was synthesised in an organic solvent for 3,h. The powder was characterised by transmission electron microscopy (TEM), and powder X-ray diffraction (XRD). The electrocatalyst consisted of agglomerates of nanometric size (,50,150,nm) particles. In the electrochemical studies, rotating disc electrode (RDE) and rotating ring-disc electrode (RRDE) techniques were used to determine the oxygen reduction kinetics in 0.5,M H2SO4. The kinetic studies include the determination of Tafel slope (112,mV,dec,1), exchange current density at 25,°C (1.48,×,10,4,mA,cm,2) and the apparent activation energy of the oxygen reaction (52.1,,,0.4,kJ,mol,1). Analysis of the data shows a multi-electron charge transfer process to water formation, with 2% H2O2 production. A single PEMFC with the RuxWySez cathode catalysts generated a power density of 180,mW,cm,2. Performance achieved with a loading of 1.4,mg,cm,2 of a 40,wt% RuxWySez and 60,wt% carbon Vulcan (i.e. 0.56,mg,cm,2 of pure RuxWySez). Single PEMFC working was obtained with hydrogen and oxygen at 80,°C with 30,psi. [source] A new method to discriminate between a valid IP response and EM coupling effectsGEOPHYSICAL PROSPECTING, Issue 6 2002Jianping Xiang ABSTRACT The problem of discrimination between a valid induced polarization (IP) response and electromagnetic (EM) coupling effects is considered and an effective solution is provided. First, a finite dimensional approximation to the Cole-Cole model is investigated. Using the least-squares approach, the parameters of the approximate model are obtained. Next, based on the analysis of overvoltage, a finite dimensional structure of the IP model is produced. Using this overvoltage-based structure, a specific finite dimensional approximation of the Cole-Cole model is proposed. Summarizing the analysis of the finite dimensional IP model, it is concluded that the proposed IP model, which fits the field data much better than the traditional Cole-Cole model, is essentially an RC-circuit. From a circuit-analysis point of view, it is well known that an electromagnetic effect can be described by an RL-circuit. The simulation results on experimental data support this conception. According to this observation, a new method to discriminate between a valid IP response and EM coupling effects is proposed as follows: (i) use a special finite dimensional model for IP,EM systems; (ii) obtain the parameters for the model using a least-squares approach; (iii) separate RC-type terms and RL-type terms , the first models the IP behaviour, the latter represents the EM part. Simulation on experimental data shows that the method is very simple and effective. [source] Interval velocity and thickness estimate from wide-angle reflection dataGEOPHYSICAL PROSPECTING, Issue 4 2001Roberto De Franco A method to estimate interval velocities and thickness in a horizontal isotropic layered medium from wide-angle reflection traveltime curves is presented. The method is based on a relationship between the squared reflection traveltime differences and the squared offset differences relative to two adjacent reflectors. The envelope of the squared-time versus offset-difference curves, for rays with the same ray parameter, is a straight line, whose slope is the inverse of the square of the interval velocity and whose intercept is the square of the interval time. The method yields velocity and thickness estimates without any knowledge of the overlying stratification. It can be applied to wide-angle reflection data when either information on the upper crust and/or refraction control on the velocity is not available. Application to synthetic and real data shows that the method, used together with other methods, allows us to define a reliable 1D starting model for estimating a depth profile using either ray tracing or another technique. [source] Changed plant and animal life cycles from 1952 to 2000 in the Mediterranean regionGLOBAL CHANGE BIOLOGY, Issue 6 2002Josep Peñuelas Abstract The available data on climate over the past century indicate that the earth is warming. Important biological effects, including changes of plant and animal life cycle events, have already been reported. However, evidence of such effects is still scarce and has been mostly limited to northern latitudes. Here we provide the first long-term (1952,2000) evidence of altered life cycles for some of the most abundant Mediterranean plants and birds, and one butterfly species. Average annual temperatures in the study area (Cardedeu, NE Spain) have increased by 1.4 °C over the observation period while precipitation remained unchanged. A conservative linear treatment of the data shows that leaves unfold on average 16 days earlier, leaves fall on average 13 days later, and plants flower on average 6 days earlier than in 1952. Fruiting occurs on average 9 days earlier than in 1974. Butterflies appear 11 days earlier, but spring migratory birds arrive 15 days later than in 1952. The stronger changes both in temperature and in phenophases timing occurred in the last 25 years. There are no significant relationships among changes in phenophases and the average date for each phenophase and species. There are not either significant differences among species with different Raunkiaer life-forms or different origin (native, exotic or agricultural). However, there is a wide range of phenological alterations among the different species, which may alter their competitive ability, and thus, their ecology and conservation, and the structure and functioning of ecosystems. Moreover, the lengthening of plant growing season in this and other northern hemisphere regions may contribute to a global increase in biospheric activity. [source] Particle beam radiotherapy for head and neck tumors: Radiobiological basis and clinical experienceHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 8 2006Barbara Alicja Jereczek-Fossa MD Abstract Background. Head and neck tumors are often located near critical organs, making it impossible to deliver a dose of conventional radiotherapy high enough to eradicate the disease. Our aim was to review the potential benefits and available clinical experience of particle beam therapy (hadrontherapy) in the treatment of these tumors. Methods. A review of the literature was carried out through a MEDLINE search (publications between 1980 and 2005). Results. A review of the available clinical data shows that particle beam therapy can offer several radiobiological and physical advantages over conventional photon radiotherapy: improved dose distribution permits dose escalation within the target and optimal sparing of normal tissue. Preclinical and clinical studies suggest that there may be benefits to using hadrontherapy for tumors characterized by poor radiosensitivity and critical location. At present, the most used hadrons are protons and, as yet on an experimental basis, carbon ions. It is now well accepted that there are certain indications for using proton therapy for skull base tumors (chordoma and chondrosarcoma), paranasal sinus carcinomas, selected nasopharyngeal tumors, and neutron/ion therapy for salivary gland carcinomas (in particular, adenoid cystic tumors). Its viability in other cases, such as locally advanced squamous cell carcinoma, melanoma, soft tissue sarcoma, and bone sarcoma, is still under investigation. Conclusions. Hadrontherapy can be beneficial in the treatment of tumors characterized by poor radiosensitivity and critical location. Further clinical and radiobiological studies are warranted for improved selection of patient population. © 2006 Wiley Periodicals, Inc. Head Neck, 2006 [source] The effect of jet array arrangement on the flow characteristics of the outlet hole in short confined channelsHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 1 2008Liu Haiyong Abstract This experimental study is part of the research program related to the aerodynamic characteristics of impingement in a confined channel. Experimental research on better understanding flow structure in confined channel with impingement cooling is rarely found in open literature. The main purposes of this project are (1) gaining greater insight into the structure of the impingement jet flow and flow in the outlet hole; (2) understanding the effect of impingement hole arrangement build up on the flow structure and aerodynamic parameters within holes and channels with different aspect ratios. The test models are two confined channels with three staggered circular jet holes, and a single large size outlet hole placed downstream of the jet plate. The structure parameters of these orifices are different. In this paper, detailed flow field in the outlet hole was measured with a straight five-hole probe, and the discharge coefficient of outlet holes with different aspect ratios was also studied in each channel. Experimental data shows that the jet arrangement has little influence on the flow behavior of the outlet hole when the aspect ratio of the passage was 1, but it played an important role on the discharge coefficient. Distinctively different flow patterns were found in two models with the aspect ratios of 3 and 5, while the variation of the discharge coefficient showed a slight influence on impingement hole arrangement. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 37(1): 20,28, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20188 [source] The economics and practicality of t-PA vs tunnel catheter replacement for hemodialysisHEMODIALYSIS INTERNATIONAL, Issue 1 2005Cairoli O. Kaiser Permanente Introduction:,Thrombolytic therapy is an important treatment modality for thrombosis-related catheter occlusion. Central venous access devices (CAVDs) are essential tools for the administration of many therapeutic modalities, especially for patients requiring lifetime therapy like hemodialysis. There are several reasons to salvage the occluded catheter. Catheter replacement results in an interruption of therapy delivery. This interruption may result in complications such as life-threatening metabolic and physiologic states. In addition, the patient's future access sites for CAVDs may be affected. The data released in the 2001 Annual Report , ESRD Clinical Performance Measures Project (Department of Health and Human Services, December 2001) shows 17% of prevalent patients were dialyzed with a chronic catheter continuously for 90 days or longer. In the pediatric population the data shows that 31% were dialyzed with a chronic catheter. The most common reasons for catheter placement included: no fistula or graft created (42%) and fistula and graft were maturing, not ready to cannulate (17%). Five percent of patients were not candidates for fistula or graft placement as all sites had been exhausted. Methods:,A short study was done in our medical center to evaluate the results of t-PA vs. changing the tunnel catheter. On an average a catheter costs about $400.00. If you add the cost of specialty personnel such as an interventional radiologist, radiology technician, radiology nurse, and the ancillaries such as the room, sutures, gauze, and tape, the total could reach $2000.00 easily. CathfloÔ Activase® costs around $60.00 for a single dose. T-PA was reconstituted by pharmacy personnel in single vials containing 2 mg/2 ml. Now with Cathflo, vials are stored in the renal clinic's refrigerator and when the need arises, the RN reconstitutes the medication. The RN, using established protocols, will instill Cathflo in the catheter following the volume requirements of the various tunnel catheters. After the t-PA is placed, the patient is sent home with instructions to return to their dialysis center the next day (arrangements are made by the RN as needed). In seventeen patients (17) with tunnel catheter malfunctions due to inadequate flow, not related to placement, t-PA was used. Of those 17 patients 2 were unable to use their catheter on their next dialysis treatment date, yielding an 88% success rate. This compares with clinical trials in which there is an 83% success rate with a dwell time of 4 hours, or an 89% rate on patients having a 2 hour dwell time (t-PA was repeated a second time if flow was not successfully restored. Results:,15/17 patients in our retrospective study showed that Cathflo worked successfully in restoring blood flow. Two catheters needed to be exchanged. The cost savings were significant when we compared the average cost of an exchange ($2000) versus using t-PA ($170 including nursing time). Conclusion:,Cathflo is not just safe and practical to use but also cost effective. [source] Ten-year study of bacteremia in hemodialysis patients in a single centerHEMODIALYSIS INTERNATIONAL, Issue 1 2005J.A. Park Background:,The incidence of infection in patients on chronic hemodialysis in higher than that of the general population. Infection is known to be a major cause of morbidity and mortality in these patients. The vascular access is important for hemodialysis, but infection through this route is the most common source of bacteremia and can be lethal to the patients. Despite the high morbidity and mortality of bacteremia in patients on chronic hemodialysis, the clinical characteristics of bacteremia in hemodialysis patients is rarely reported yet in Korea. Methods:,We included 696 hemodialysis patients from January 1993 to December 2003 at Uijongbu St. Mary's Hospital. We investigated incidence, source, causative organisms, clinical manifestations, complication, and mortality of bacteremia. We compared clinical factors, morbidity, and mortality between arteriovenous fistula and central venous catheter groups. Results:,Total 52 cases of bacteremia occurred in 43 patients. The major source of infection was vascular access (48%). Staphylococcus aureus was most common organism isolated. Major complications were septic shock (9.6%), pneumonia (9.6%), infective endocarditis (3.8%), and aortic pseudoaneurysm (1.9%). Nine patients died from septic shock (n = 4), aspiration pneumonia (n = 2), hypoxic brain injury (n = 1), gastrointestinal bleeding (n = 1), and rupture of aortic pseudoaneurysm. The central venous catheter group (n = 22) had higher incidences of vascular access as a source of infection (81.8% vs 23.3%, p < 0.001) and staphylococcus as a causative organism (77.2% vs 50.0%, p = 0.042) than the arteriovenous group. Conclusion:, This data shows that bacteremia causes high incidence of fatal complications and mortality. Therefore, careful management of vascular access as well as early detection of bacteremia is an important factor for the prevention of infection and proper antibiotic therapy should be started early. [source] Different methods for modelling the areal infiltration of a grass field under heavy precipitationHYDROLOGICAL PROCESSES, Issue 7 2002Bruno Merz Abstract The areal infiltration behaviour of a grass field is studied using a data set of 78 sprinkler infiltration experiments. The analysis of the experimental data shows a distinct event dependency: once runoff begins, the final infiltration rate increases with increasing rainfall intensity. This behaviour is attributed to the effects of small-scale variability. Increasing rainfall intensity increases the ponded area and therefore the portion of the plot which infiltrates at maximum rate. To describe the areal infiltration behaviour of the grass field the study uses two different model structures and investigates different approaches for consideration of subgrid variability. It is found that the effective parameter approach is not suited for this purpose. A good representation of the observed behaviour is obtained by using a distribution function approach or a parameterization approach. However, it is not clear how the parameters can be derived for these two approaches without a large measurement campaign. The data analysis and the simulations show the great importance of considering the effects of spatial variability for the infiltration process. This may be significant even at a small scale for a comparatively homogeneous area. The consideration of heterogeneity seems to be more important than the choice of the model type. Furthermore, similar results may be obtained with different modelling approaches. Even the relatively detailed data set does not seem to permit a clear model choice. In view of these results it is questionable to use very complex and detailed simulation models given the approximate nature of the problem. Although the principle processes may be well understood there is a lack of models that represent these processes and, more importantly, there is a lack of techniques to measure and parameterize them. Copyright © 2002 John Wiley & Sons, Ltd. [source] When home is in jail: child development in Spanish penitentiary unitsINFANT AND CHILD DEVELOPMENT, Issue 5 2003Jesús M. Jiménez Abstract The quality of the educational family context of children who live with their mothers in prison (N=127, age M=16.3 months) as well as how this situation affects their level of development are analysed. The assessment of these contexts was carried out using the HOME scale. The evaluation of the children's development was carried out using the Brunet,Lézine scale. The data shows that the quality of this context is extremely low, with one of the most striking features being the low score obtained in the subscales of provision of play materials and variety of experiences. Moreover, there are significant differences in the scores that are related to the mother's level of education, ethnic origins and the type of prison where they are serving their sentences. As for the scores obtained by the children in the Brunet,Lézine scale, the data shows that their level of development is similar to that of the infant population in general although we also found that the development quotients of the children in the group with the lowest scores in the HOME scale tend to drop significantly after 18 months of age. The results are discussed taking into account the interaction of context and development under the light of the canalization hypothesis, and making some suggestions about possible ways to improve these children's life conditions. Copyright © 2003 John Wiley & Sons, Ltd. [source] Numerical modelling of hydro-mechanical behaviour of collapsible soilsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 12 2008L. M. Costa Abstract This paper presents a numerical simulation of the response of unsaturated soil under different loads, with special attention devoted to the phenomenon of pore collapse during wetting. A coupled hydro-mechanical formulation, implemented in the computational code CODE_BRIGHT, is first presented. Then the model is applied to assess material parameter from laboratory tests and to simulate, as boundary value problems, new and appealing in situ tests designed in the Federal University of Pernambuco. The soil considered is a collapsible soil located in the semi-arid region of the northeast of Brazil. Two situations are analysed: (i) the soil is initially at its natural water content and then flooded at some determined stress level, (ii) the soil is previously flooded and then loaded. Comparison between output results of numerical simulations and experimental data shows a very good agreement, which validate to some extent the proposed experimental procedure and the model formulation. Copyright © 2007 John Wiley & Sons, Ltd. [source] Long-term changes and regional differences in temperature and precipitation in the metropolitan area of HamburgINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 8 2010K. H. Schlünzen Abstract Climate changes and the urban climate of the ,green city' Hamburg and its metropolitan region are analyzed using observational data for temperature and precipitation. Values for Hamburg's synoptic site HH-Fuhlsbüttel start in 1891 and are used to determine climate changes. Additional data from up to 45 climate stations are used to analyze the different aspects of the regional climate and urban effects on the temperature [urban heat island (UHI)] and precipitation [urban precipitation impact (UPI)]. The analysis of the long-term data shows that the climate has already changed. Annual precipitation significantly increases ,0.8 mm/year when focusing on years 1891,2007 and ,1.3 mm/year for 1948,2007. Precipitation increases are largest in November through March and March as well as June for 1978,2007. For April and July of this period, a precipitation decrease is found. The precipitation distribution shows that moderate daily precipitation amounts (,10 mm/day) have increased by about 10% between 1948,1977 and 1978,2007. Precipitation amounts > 10 mm/day have increased by 20% in the same period. Average temperatures significantly increase by 0.07 K/decade (1891,2007), 0.19 K/decade (1948,2007), 0.6 K/decade (1978,2007) with largest significant increases in fall. For the UHI, it is found that the average temperature is higher up to 1.1 K in the densely build-up city area than outside. Values are about halved for more green urban areas but also depend on more local impacts. The minimum temperatures are up to 3 K higher and maximum temperatures slightly lower in the inner city than in the rural during summer. The winter temperatures are higher throughout the urban area. The UHI differences depend on wind speed; this dependence is best described by using the inverse square root of the wind speed. Classification using different wind directions shows that the precipitation is significantly higher (5,20%) for downwind of urban areas compared with the upwind side. Copyright © 2009 Royal Meteorological Society [source] Transport mechanisms and performance simulation of a PEM fuel cellINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 6 2008Geng-Po Ren Abstract A three-dimensional, gas,liquid two-phase flow and transport model has been developed and utilized to simulate the multi-dimensional, multi-phase flow and transport phenomena in both the anode and cathode sides in a proton exchange membrane (PEM) fuel cell and the cell performance with different influencing operational and geometric parameters. The simulations are presented with an emphasis on the physical insight and fundamental understanding afforded by the detailed distributions of velocity vector, oxygen concentration, water vapor concentration, liquid water concentration, water content in the PEM, net water flux per proton flux, local current density, and overpotential. Cell performances with different influencing factors are also presented and discussed. The comparison of the model prediction and experimental data shows a good agreement. Copyright © 2007 John Wiley & Sons, Ltd. [source] Poly(O -anisidine) coatings electrodeposited onto AL-2024: Synthesis, characterization, and corrosion protection evaluationADVANCES IN POLYMER TECHNOLOGY, Issue 4 2004Kunal Shah Abstract Poly(O -anisidine) coating was successfully electrodeposited onto Al-2024. Cyclic voltammetry and reflection absorption infrared spectroscopy (RAIR) analysis were carried out in order to fully understand the formation and structure of the resulting polymer coating. RAIR spectrum showed the characteristics peaks of poly(O -anisidine). As the reaction time was varied, the CV peak shifted from 0.75 to 0.81 V vs. SCE suggesting that a change in structure of the polymer from a reduced state to a partially oxidized form has occurred. UV spectrum showed two peaks at 320 and 620 nm suggesting the presence of conjugation on the polymer backbone. The deposition of the poly(O -anisidine) onto the substrate was controlled by nucleation and growth mechanism. DC polarization technique was used to evaluate the corrosion protection offered by poly(O -anisidine) coatings. Preliminarily data shows that these coatings help to ennoble the surface of the substrate. © 2004 Wiley Periodicals, Inc. Adv Polym Techn 23: 291,297, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20024 [source] Is there a ,New Managerial Work'?JOURNAL OF MANAGEMENT STUDIES, Issue 7 2006A Comparison with Henry Mintzberg's Classic Study 30 Years Later abstract This comparative study of top executives' work aimed at examining the stability of top managerial behaviour reveals a relatively different pattern of behaviour compared with the study by Henry Mintzberg. The main differences are a much larger workload, a contact pattern to a larger degree oriented towards subordinates in group-settings, a greater emphasis on giving information, and less preoccupation with administrative work. One important finding is that fragmentation of time , in previous studies highlighted as a central tenet of managerial work , was not as prevalent in the new study. The different results can be attributed (with caution) to the impact of the management discourse about leadership and corporate culture, and to factors such as organizational structure and geographical dispersion of companies. However, there are also significant similarities between the two studies which indicate that claims of the emergence of a radically different managerial work are much exaggerated. Instead the empirical data shows that new work-practices are combined with older practices, both in a complex and context-specific ways. Therefore, there is a need for better integration between theoretical development and empirical investigations in this field of inquiry. [source] Phase separation of liquid-liquid two-phase flow at a T-junctionAICHE JOURNAL, Issue 1 2006L. Yang Abstract The phase separation of liquid-liquid two-phase flow at a T-junction has been studied using kerosene and deionized water as working fluids and a T-junction with a horizontal main pipe and a vertically upward side arm. Separation data are evaluated by a new criterion: separation efficiency. The results show that the T-junction is highly efficient at separating two immiscible liquids when the flows approaching the T-junction are stratified and when the fractional mass take offs close to the inlet kerosene mass fraction. A new model has been proposed for the phase separation. Comparison between the model and the experimental data shows that the data is well represented by the model. © 2005 American Institute of Chemical Engineers AIChE J, 2006 [source] Application of the transformed Potts,Guy equation to in vivo human skin dataJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 9 2001William J. Roberts Abstract Data developed by Wenkers and Lippold for the flux of 10 nonsteroidal anti-inflammatory drugs from light mineral oil (MO) through human skin in vivo has been analyzed using the transformed Potts,Guy equation. The analysis shows that the flux is dependent not only on the solubility in MO (SMO), but also on the solubility in acidic water (SAQ). This dependence of flux on SAQ shows that the previously reported dependence of flux on SAQ from in vitro experiments using hairless mouse skin is not an artifact of the in vitro experiments but is due to a characteristic of the skin barrier. Further inspection of the equations used by Wenkers and Lippold in their analyses of their data shows that the equations are variations of the transformed Potts,Guy equation. © 2001 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 90:1318,1323, 2001 [source] Enhancing the quality of argumentation in school scienceJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 10 2004Jonathan Osborne The research reported in this study focuses on the design and evaluation of learning environments that support the teaching and learning of argumentation in a scientific context. The research took place over 2 years, between 1999 and 2001, in junior high schools in the greater London area. The research was conducted in two phases. In phase 1, working with a group of 12 science teachers, the main emphasis was to develop sets of materials and strategies to support argumentation in the classroom, and to support and assess teachers' development with teaching argumentation. Data were collected by video- and audio-recording the teachers' attempts to implement these lessons at the beginning and end of the year. During this phase, analytical tools for evaluating the quality of argumentation were developed based on Toulmin's argument pattern. Analysis of the data shows that there was significant development in the majority of teachers use of argumentation across the year. Results indicate that the pattern of use of argumentation is teacher-specific, as is the nature of the change. In phase 2 of the project, the focus of this paper, teachers taught the experimental groups a minimum of nine lessons which involved socioscientific or scientific argumentation. In addition, these teachers taught similar lessons to a comparison group at the beginning and end of the year. The purpose of this research was to assess the progression in student capabilities with argumentation. For this purpose, data were collected from 33 lessons by video-taping two groups of four students in each class engaging in argumentation. Using a framework for evaluating the nature of the discourse and its quality developed from Toulmin's argument pattern, the findings show that there was improvement in the quality of students' argumentation. This research presents new methodological developments for work in this field. © 2004 Wiley Periodicals, Inc. J Res Sci Teach 41: 994,1020, 2004 [source] Proton Conductivity Measurements in Yttrium Barium Cerate by Impedance SpectroscopyJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2002W. Grover Coors Proton-conducting solid-electrolyte perovskite ceramics based on acceptor-doped barium and strontium cerates have become the focus of extensive investigations as candidate materials for fuel cells that operate at moderate temperatures. To assess the suitability of a material for this application, it is necessary that bulk electrolyte conductivity be measured at the operating temperature. However, very little reliable published conductivity data exist above 600°C. Protonic conductivity in yttrium-doped barium cerate has been observed to be less at high temperatures than would be expected, based on the activation energy and preexponential for hydrogen transport at temperatures <300°C. Conductivity data obtained from impedance spectroscopy on BaCe0.9Y0.1O3,, over the extended temperature range of 100°,900°C are presented. An Arrhenius plot of the data shows two distinct linear regions, suggesting that two different rate-limiting processes occur in series with a break-over transition at ,250°C. The decrease in conductivity is apparently not due to dehydration. An activation energy for protonic transport of 0.26 eV, about one-half of the low-temperature value, is proposed, based on curve fitting of the high-temperature data. [source] | ||||||||||||||||||||||||||||||||||||||||