The efficacy of fluid-gas exchange for the treatment of postvitrectomy retinal detachment.

PubMed

Jang, Ji Hye; Kim, Yu Cheol; Kim, Kwang Soo

2009-12-01

This study was designed to evaluate the efficacy of fluid-gas exchange for the treatment of postvitrectomy retinal detachment. We retrospectively reviewed the records of 33 consecutive patients (35 eyes) who underwent fluid-gas exchange treatment for postvitrectomy retinal detachment using the two-needle pars plana approach technique. The retinal reattachment rate was 80.0% after complete intravitreal gas disappearance following the fluid-gas exchange; the overall success rate was 65.7%. Visual acuity was improved or stable in 80.0% of cases; a two-line or greater vision improvement or a best-corrected visual acuity of 0.4 or better occurred in 62.9% of cases. The success rates for superior retinal detachments and posterior pole retinal detachments were 76.5% and 85.7%, respectively. Fluid-gas exchange represents a simple and cost-effective alternative outpatient procedure for retinal reattachment without reoperation for the treatment of superior and posterior pole retinal detachments.

Physical explosion analysis in heat exchanger network design

NASA Astrophysics Data System (ADS)

Pasha, M.; Zaini, D.; Shariff, A. M.

2016-06-01

The failure of shell and tube heat exchangers is being extensively experienced by the chemical process industries. This failure can create a loss of production for long time duration. Moreover, loss of containment through heat exchanger could potentially lead to a credible event such as fire, explosion and toxic release. There is a need to analyse the possible worst case effect originated from the loss of containment of the heat exchanger at the early design stage. Physical explosion analysis during the heat exchanger network design is presented in this work. Baker and Prugh explosion models are deployed for assessing the explosion effect. Microsoft Excel integrated with process design simulator through object linking and embedded (OLE) automation for this analysis. Aspen HYSYS V (8.0) used as a simulation platform in this work. A typical heat exchanger network of steam reforming and shift conversion process was presented as a case study. It is investigated from this analysis that overpressure generated from the physical explosion of each heat exchanger can be estimated in a more precise manner by using Prugh model. The present work could potentially assist the design engineer to identify the critical heat exchanger in the network at the preliminary design stage.

Complications of Impulse Generator Exchange Surgery for Deep Brain Stimulation: A Single-Center, Retrospective Study.

PubMed

Helmers, Ann-Kristin; Lübbing, Isabel; Birkenfeld, Falk; Witt, Karsten; Synowitz, Michael; Mehdorn, Hubertus Maximilian; Falk, Daniela

2018-05-01

Nonrechargeable deep brain stimulation impulse generators (IGs) with low or empty battery status require surgical IG exchange several years after initial implantation. The aim of this study was to investigate complication rates after IG exchange surgery and identify risk factors. We retrospectively analyzed complications following IG exchange surgery from 2008 to 2015 in our department. Medical records of all patients who underwent IG exchange surgery were systematically reviewed. The shortest follow-up time was 19 months. From 2008 to 2015, 438 IGs were exchanged in 319 patients. Overall complication rate was 8.90%. Infection developed in 12 patients (2.74%). Six patients (1.37%) experienced local wound erosions. Hardware malfunctions were present in 11 patients (2.51%), and local hemorrhage was observed in 3 cases (0.68%). Repeated fixation of the IG was required in 2 patients (0.46%). Traction of the connecting cables necessitated surgical revision in 2 patients (0.46%). In 2 cases (0.46%), the IG was placed abdominally or exchanged for a smaller device owing to patient discomfort resulting from the initial positioning. One 80-year-old patient (0.23%) had severely worsening heart failure and died 4 days after IG exchange surgery. IG exchange surgery, although often considered a minor surgery, was associated with a complication rate of approximately 9% in our center. Patients and physicians should understand the complication rates associated with IG exchange surgery because this information might facilitate selection of a rechargeable IG. Copyright © 2018 Elsevier Inc. All rights reserved.

Examining the reaction of monetary policy to exchange rate changes: A nonlinear ARDL approach

NASA Astrophysics Data System (ADS)

Manogaran, Lavaneesvari; Sek, Siok Kun

2017-04-01

Previous studies showed the exchange rate changes can have significant impacts on macroeconomic performance. Over fluctuation of exchange rate may lead to economic instability. Hence, monetary policy rule tends to react to exchange rate changes. Especially, in emerging economies where the policy-maker tends to limit the exchange rate movement through interventions. In this study, we seek to investigate how the monetary policy rule reacts to exchange rate changes. The nonlinear autoregressive distributed lag (NARDL) model is applied to capture the asymmetric effect of exchange rate changes on monetary policy reaction function (interest rate). We focus the study in ASEAN5 countries (Indonesia, Malaysia, Philippines, Thailand and Singapore). The results indicated the existence of asymmetric effect of exchange rates changes on the monetary reaction function for all ASEAN5 countries in the long-run. Where, in majority of the cases the monetary policy is reacting to the appreciation and depreciation of exchange rate by raising the policy rate. This affirms the intervention of policymakers with the `fear of floating' behavior.

Can Vocational Programmes Change Use and Exchange Value Attributions of School Leavers: A Kenyan Case Study?

ERIC Educational Resources Information Center

Saunders, Murray; Sambili, Helen

1995-01-01

A survey of Kenyan school leavers (200 responses) and 34 interviews show that the exchange value of school-leaving exams is predominant and the use value of vocational programs has little impact. Apparently, 80% of school effort has actual exchange value for only 20% of school leavers, whereas 20% of effort directed at self-employment has…

Study of transient behavior of finned coil heat exchangers

NASA Technical Reports Server (NTRS)

Rooke, S. P.; Elissa, M. G.

1993-01-01

The status of research on the transient behavior of finned coil cross-flow heat exchangers using single phase fluids is reviewed. Applications with available analytical or numerical solutions are discussed. Investigation of water-to-air type cross-flow finned tube heat exchangers is examined through the use of simplified governing equations and an up-wind finite difference scheme. The degenerate case of zero air-side capacitance rate is compared with available exact solution. Generalization of the numerical model is discussed for application to multi-row multi-circuit heat exchangers.

Left ventricular assist device exchange: the Toronto General Hospital experience.

PubMed

Tsubota, Hideki; Ribeiro, Roberto V P; Billia, Filio; Cusimano, Robert J; Yau, Terrence M; Badiwala, Mitesh V; Stansfield, William E; Rao, Vivek

2017-08-01

As support times for left ventricular assist devices (LVADs) become longer, several complications requiring device exchange may occur. To our knowledge, this is the first Canadian report regarding implantable LVAD exchange. We retrospectively reviewed the cases of consecutive, unique patients implanted with an LVAD between June 2006 and October 2015 at Toronto General Hospital. In total, 122 patients were impanted with an LVAD during the study period. Eight patients required LVAD exchange, and 1 patient had 2 replacements (9 of 122, 7.3%). There were 7 HeartMate II (HMII), 1 HVAD and 1 DuraHeart pumps exchanged. Two of these exchanges occurred early at the time of initial implant, whereas 7 occurred late (range 8-623 d). Six exchanges were made owing to pump thrombosis. Of the 3 exchanges made for other causes, 1 HMII exchange was owing to a driveline fracture, 1 DuraHeart patient had early inflow obstruction requiring exchange to HMII at the initial implant, and the third had a suspected inflow obstruction with no evidence of thrombosis at the time of the procedure. The mean support time before exchange was 225 days, and time from exchange to transplant, death or ongoing support was 245 days. Three patients were successfully bridged to transplant, and at the time of data collection 2 were supported awaiting transplant. Three patients died after a mean duration of 394.3 days (range 78-673 d) of support postreplacement. Four cases were successfully performed using a subcostal approach. Pump thrombosis is the most common cause for LVAD exchange, which can be performed with acceptable morbidity and mortality. The subcostal approach may be the preferred procedure for an HMII exchange when indicated.

Structural approaches to knowledge exchange: comparing practices across five centres of excellence in public health.

PubMed

Van der Graaf, P; Francis, O; Doe, E; Barrett, E; O'Rorke, M; Docherty, G

2018-03-01

In 2008, five UKCRC Public Health Research Centres of Excellence were created to develop a coordinated approach to policy and practice engagement and knowledge exchange. The five Centres have developed their own models and practices for achieving these aims, which have not been compared in detail to date. We applied an extended version of Saner's model for the interface between science and policy to compare five case studies of knowledge exchanges, one from each centre. We compared these practices on three dimensions within our model (focus, function and type/scale) to identify barriers and facilitators for knowledge exchange. The case studies shared commonalities in their range of activities (type) but illustrated different ways of linking these activities (function). The Centres' approaches ranged from structural to more organic, and varied in the extent that they engaged internal audiences (focus). Each centre addressed policymakers at different geographical levels and scale. This article emphasizes the importance of linking a range of activities that engage policymakers at different levels, intensities and points in their decision-making processes to build relationships. Developing a structural approach to knowledge exchange activities in different contexts presents challenges of resource, implementation and evaluation.

Exploring knowledge exchange at the research-policy-practice interface in children's behavioral health services.

PubMed

Leslie, Laurel K; Maciolek, Susan; Biebel, Kathleen; Debordes-Jackson, Gifty; Nicholson, Joanne

2014-11-01

This case study explored core components of knowledge exchange among researchers, policymakers, and practitioners within the context of the Rosie D. versus Romney class action lawsuit in Massachusetts and the development and implementation of its remedial plan. We identified three distinct, sequential knowledge exchange episodes with different purposes, stakeholders, and knowledge exchanged, as decision-making moved from Federal Medicaid policy to state Medicaid program standards and to community-level practice. The knowledge exchanged included research regarding Wraparound, a key component of the remedial plan, as well as contextual information critical for implementation (e.g., Federal Medicaid policy, managed care requirements, community organizations' characteristics).

China’s Democratization Prospects: A Comparative Analysis

DTIC Science & Technology

2014-03-01

17 G. CONCLUSION ..............................................................................................19 III. TAIWAN CASE ...31 IV. SOUTH KOREA CASE STUDY...especially to the United States for trade, cultural exchanges and tourism 16 Ibid. 17 John Fuh-sheng

Absorbing Australian Culture through the Exchange Program at RMIT International University in Vietnam

ERIC Educational Resources Information Center

Chi, Nguyen Ho Phuong

2013-01-01

This paper outlines a case study of four Vietnamese students who have just completed their exchange semester at RMIT University, Melbourne. Results indicate that the students appreciate multiple benefits brought by this experience, including a developing sense of language use, responsibility, dependence, self-awareness, integration, and…

Tandem Translation Classroom: A Case Study

ERIC Educational Resources Information Center

Kim, Dohun; Koh, Taejin

2018-01-01

The transition to student-centred learning, advances in teleconferencing tools, and active international student exchange programmes have stimulated tandem learning in many parts of the world. This pedagogical model is based on a mutual language exchange between tandem partners, where each student is a native speaker in the language the…

A design study of hydrazine and biowaste resistojets

NASA Technical Reports Server (NTRS)

Page, R. J.; Stoner, W. A.; Barker, L.

1986-01-01

A generalized modeling program was adapted in BASIC on a personal computer to compare the performance of four types of biowaste resistojets and two types of hydrazine augmenters. Analyzed biowaste design types were: (1) an electrically conductive ceramic heater-exchanger of zirconia; (2) a truss heater of platinum in cross flow; (3) an immersed bicoiled tubular heater-exchanger; and (4) a nonexposed, refractory metal, radiant heater in a central cavity within a heat exchanger case. Concepts 2 and 3 are designed to have an efficient, stainless steel outer pressure case. The hydrazine design types are: (5) an immersed bicoil heater exchanger and (6) a nonexposed radiant heater now with a refractory metal case. The ceramic biowaste resistojet has the highest specific impulse growth potential at 2000 K of 192.5 (CO2) and 269 s (H2O). The bicoil produces the highest augmenter temperature of 1994 K for a 2073 K heater giving 317 s at .73 overall efficiency. Detailed temperature profiles of each of the designs are shown. The scaled layout drawings of each are presented with recommended materials and fabrication methods.

Agreement between pre-operative and intra-operative bacteriological samples in 85 chronic peri-prosthetic infections.

PubMed

Matter-Parrat, V; Ronde-Oustau, C; Boéri, C; Gaudias, J; Jenny, J-Y

2017-04-01

Whether pre-operative microbiological sampling contributes to the management of chronic peri-prosthetic infection remains controversial. We assessed agreement between the results of pre-operative and intra-operative samples in patients undergoing single-stage prosthesis exchange to treat chronic peri-prosthetic infection. Agreement between pre-operative and intra-operative samples exceeds 75% in patients undergoing single-stage exchange of a hip or knee prosthesis to treat chronic peri-prosthetic infection. This single-centre retrospective study included 85 single-stage prosthesis exchange procedures in 82 patients with chronic peri-prosthetic infection at the hip or knee. Agreement between pre-operative and intra-operative sample results was evaluated. Changes to the initial antibiotic regimen made based on the intra-operative sample results were recorded. Of 149 pre-operative samples, 109 yielded positive cultures, in 75/85 cases. Of 452 intra-operative samples, 354 yielded positive cultures, in 85/85 cases. Agreement was complete in 54 (63%) cases and partial in 9 (11%) cases; there was no agreement in the remaining 22 (26%) cases. The complete agreement rate was significantly lower than 75% (P=0.01). The initial antibiotic regimen was inadequate in a single case. Pre-operative sampling may contribute to the diagnosis of peri-prosthetic infection but is neither necessary nor sufficient to confirm the diagnosis and identify the causative agent. The spectrum of the initial antibiotic regimen cannot be safely narrowed based on the pre-operative sample results. We suggest the routine prescription of a probabilistic broad-spectrum antibiotic regimen immediately after the prosthesis exchange, even when a pathogen was identified before surgery. IV, retrospective study. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

[Screening program for tuberculosis among international exchange students in the Department of Isère].

PubMed

Albahary, M-V; Blanc-Jouvan, F; Recule, C; Dubey, C; Pavese, P

2018-01-01

France is a low-incidence country for tuberculosis (TB). Consequently screening is focused on high-risk populations, in particular migrants. The aim of this study was to evaluate the epidemiology of TB among international exchange students in the Department of Isère and the screening programs used. We carried out an organizational audit based on interviews with physicians involved in the management of TB in Isère. We conducted a retrospective descriptive study based on a case series of foreign students treated for TB from 2003 to 2013 inclusively. Forty-six international exchange students were treated for active TB during this time, representing an average incidence of 284/100,000. Two thirds of our studied population were Africans, 72% were asymptomatic at the time of screening. A quarter of our cohort developed TB after the initial screening. Thirty-one cases were confirmed bacteriologically, mainly through bronchoscopy. Outcome (radiological and clinical) on quadruple therapy was satisfactory in all patients. Two patients relapsed, one of them with multi-drug resistant TB. Our work confirms that international exchange students are a population at high risk of TB and that screening of this population is essential. The significant number of active TB cases diagnosed after the initial screening stresses the importance of diagnosis and follow up of patients with latent TB infection. Copyright © 2017 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Experimental study of copper-alkali ion exchange in glass

NASA Astrophysics Data System (ADS)

Gonella, F.; Caccavale, F.; Bogomolova, L. D.; D'Acapito, F.; Quaranta, A.

1998-02-01

Copper-alkali ion exchange was performed by immersing different silicate glasses (soda-lime and BK7) in different molten eutectic salt baths (CuSO4:Na2SO4 and CuSO4:K2SO4). The obtained optical waveguides were characterized by m-lines spectroscopy for the determination of refractive index profiles, and by secondary ion mass spectrometry for the concentration profiles of the ion species involved in the exchange process. The different oxidation states of copper inside the glass structure were studied by electron paramagnetic resonance and x-ray absorption techniques. Interdiffusion copper coefficients were also determined. The Cu-alkali exchange was observed to give rise to local structural rearrangement of the atoms in the glass matrix. The Cu+ ion was found to mainly govern the exchange process, while competition between Cu-Na and K-Na exchanges occurred when a potassium sulfate bath was used. In this case, significant waveguide modal birefringence was observed.

Entropy Generation in Regenerative Systems

NASA Technical Reports Server (NTRS)

Kittel, Peter

1995-01-01

Heat exchange to the oscillating flows in regenerative coolers generates entropy. These flows are characterized by oscillating mass flows and oscillating temperatures. Heat is transferred between the flow and heat exchangers and regenerators. In the former case, there is a steady temperature difference between the flow and the heat exchangers. In the latter case, there is no mean temperature difference. In this paper a mathematical model of the entropy generated is developed for both cases. Estimates of the entropy generated by this process are given for oscillating flows in heat exchangers and in regenerators. The practical significance of this entropy is also discussed.

Interlayer exchange coupling in complex magnetic multilayers

NASA Astrophysics Data System (ADS)

Xiang-dong, Zhang; Lie-ming, Li; Bo-zang, Li; Fu-cho, Pu

1998-07-01

We extend the hole confinement model of Edwards et al. to the problem of two kinds of complex magnetic sandwich structures. One is the magnetic sandwich covered on both sides by nonmagnetic films (case 1) and the other is that covered by magnetic films (case 2). The interlayer exchange coupling and the angular dependence of coupling energy in the two cases are investigated systematically. For case 1, our results show that the magnetic and outer nonmagnetic films influence significantly the oscillation behavior of exchange coupling and the appearance of noncollinear exchange coupling is very sensitive to the thickness of magnetic and outer nonmagnetic layers. Our results also show that the nonoscillatory component of the coupling generally varies with the thickness of magnetic (outer nonmagnetic) films and the results in the case where the thickness of both magnetic (outer nonmagnetic) films vary simultaneously are significantly different from that in the case where the thickness of one of the two magnetic (outer nonmagnetic) films is fixed while the other is varied, which is qualitatively in agreement with the experimental measurements. For case 2, the exponential dependence of exchange coupling on the thickness of the intermagnetic layer has been obtained, similar to the Parkin's experimental results for giant magnetoresistance.

Community Music Knowledge Exchange Research in Scottish Higher Education

ERIC Educational Resources Information Center

Moran, Nikki; Loening, Gica

2011-01-01

This article examines the usefulness of Knowledge Exchange (KE) funding streams for higher education community music research projects, with a case study of one particular project that took place between February and April 2010. The project was funded via a KE stream, linking University researchers with a well-established community music charity…

Public-Private Interorganizational Sharing of Health Data for Disability Determination

ERIC Educational Resources Information Center

Feldman, Sue S.

2011-01-01

Information exchange is a cornerstone in facilitating a strategic advantage in business. However, health information exchange has not shared that same foundation in health care and related secondary uses, especially when the information is used for something other than diagnosis, treatment, or payment. This case study provides an in-depth…

Gas phase 1H NMR studies and kinetic modeling of dihydrogen isotope equilibration catalyzed by Ru-nanoparticles under normal conditions: dissociative vs. associative exchange.

PubMed

Limbach, Hans-Heinrich; Pery, Tal; Rothermel, Niels; Chaudret, Bruno; Gutmann, Torsten; Buntkowsky, Gerd

2018-04-25

The equilibration of H2, HD and D2 between the gas phase and surface hydrides of solid organic-ligand-stabilized Ru metal nanoparticles has been studied by gas phase 1H NMR spectroscopy using closed NMR tubes as batch reactors at room temperature and 800 mbar. When two different nanoparticle systems, Ru/PVP (PVP ≡ polyvinylpyrrolidone) and Ru/HDA (HDA ≡ hexadecylamine) were exposed to D2 gas, only the release of HD from the hydride containing surface could be detected in the initial stages of the reaction, but no H2. In the case of Ru/HDA also the reverse experiment was performed where surface deuterated nanoparticles were exposed to H2. In that case, the conversion of H2 into gaseous HD was detected. In order to analyze the experimental kinetic and spectroscopic data, we explored two different mechanisms taking into account potential kinetic and equilibrium H/D isotope effects. Firstly, we explored the dissociative exchange mechanism consisting of dissociative adsorption of dihydrogen, fast hydride surface diffusion and associative desorption of dihydrogen. It is shown that if D2 is the reaction partner, only H2 will be released in the beginning of the reaction, and HD only in later reaction stages. The second mechanism, dubbed here associative exchange consists of the binding of dihydrogen to Ru surface atoms, followed by a H-transfer to or by H-exchange with an adjacent hydride site, and finally of the associative desorption of dihydrogen. In that case, in the exchange with D2, only HD will be released in the beginning of the reaction. Our experimental results are not compatible with the dissociative exchange but can be explained in terms of the associative exchange. Whereas the former will dominate at low temperatures and pressures, the latter will prevail around room temperature and normal pressures where transition metal nanoparticles are generally used as reaction catalysts.

Life cycle design metrics for energy generation technologies: Method, data, and case study

NASA Astrophysics Data System (ADS)

Cooper, Joyce; Lee, Seung-Jin; Elter, John; Boussu, Jeff; Boman, Sarah

A method to assist in the rapid preparation of Life Cycle Assessments of emerging energy generation technologies is presented and applied to distributed proton exchange membrane fuel cell systems. The method develops life cycle environmental design metrics and allows variations in hardware materials, transportation scenarios, assembly energy use, operating performance and consumables, and fuels and fuel production scenarios to be modeled and comparisons to competing systems to be made. Data and results are based on publicly available U.S. Life Cycle Assessment data sources and are formulated to allow the environmental impact weighting scheme to be specified. A case study evaluates improvements in efficiency and in materials recycling and compares distributed proton exchange membrane fuel cell systems to other distributed generation options. The results reveal the importance of sensitivity analysis and system efficiency in interpreting case studies.

Population-based Incidence of Intraocular Lens Exchange in Olmsted County, Minnesota.

PubMed

Bothun, Erick D; Cavalcante, Lilian C B; Hodge, David O; Patel, Sanjay V

2018-03-01

To determine the population-based incidence of pseudophakic intraocular lens exchange in Olmsted County, Minnesota. Retrospective review of a population-based cohort. Patients undergoing pseudophakic intraocular lens exchange in Olmsted County, Minnesota, between January 1, 1986 and December 31, 2016 were identified from the Rochester Epidemiology Project medical record linkage system. Indications and outcomes were determined, and the incidence rate was calculated as cases per 1 000 000 person-years. Poisson regression analysis was used to assess changes in incidence over time, and the cumulative probability of needing a lens exchange was estimated by Kaplan-Meier analysis. Eighty cases of intraocular lens exchange were identified, yielding an overall age- and sex-adjusted incidence rate of 28.4 per million (confidence interval [CI], 22.1-34.7), which increased over the study period (P = .04). The 30-year cumulative probability of intraocular lens exchange among patients undergoing cataract surgery was 1.5% (CI, 0.6%-2.4%), increasing at a relatively constant rate. Dislocated lenses accounted for 72.5% of lens exchanges. Unplanned refractive outcome of primary cataract surgery and uveitis-glaucoma-hyphema syndrome from squared-edged haptics emerged as newer indications for intraocular lens exchange. The population-based incidence of pseudophakic intraocular lens exchange has increased over the last 30 years, and can be explained by the increase in incidence rate of cataract surgery over the same period. Surgeons should be aware of emerging indications of intraocular lens exchange, which reflect changes in lens design and increasing expectations of refractive outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

A Case of Clinically Amyopathic Dermatomyositis with Interstitial Pneumonia that Was Successfully Treated with Plasma Exchange.

PubMed

Yagishita, Mizuki; Kondo, Yuya; Terasaki, Toshihiko; Terasaki, Mayu; Shimizu, Masaru; Honda, Fumika; Oyama, Ayako; Takahashi, Hiroyuki; Yokosawa, Masahiro; Asashima, Hiromitsu; Hagiwara, Shinya; Tsuboi, Hiroto; Matsumoto, Isao; Sumida, Takayuki

2018-02-28

Patients with clinically amyopathic dermatomyositis (CADM), a subset of dermatomyositis characterized by a lack of muscle involvement, frequently develop rapidly progressive and treatment-resistant interstitial lung disease. We report the case of a 49-year-old man who was diagnosed with CADM. He developed interstitial pneumonia, which did not respond to combination therapy with methylprednisolone pulse therapy, cyclophosphamide, and cyclosporine. We therefore attempted plasma exchange. After 7 courses of therapeutic plasma exchange, the interstitial pneumonia gradually improved. This case suggests that plasma exchange might be an effective therapeutic option for patients with progressive interstitial lung disease in steroid- and immunosuppressive therapy-refractive CADM.

The role of red blood cell exchange for severe imported malaria in the artesunate era: a retrospective cohort study in a referral centre.

PubMed

Calvo-Cano, Antonia; Gómez-Junyent, Joan; Lozano, Miguel; Castro, Pedro; Cid, Joan; Nicolás, Jose María; Quintó, Llorenç; Martin, Maite; Muñoz, Jose; Gascon, Joaquim

2016-04-14

Intravenous artesunate has replaced quinine as the first-line therapy for severe imported malaria, given its anti-malarial superiority shown in clinical trials conducted in endemic countries. Evidence for red blood cell (RBC) exchange in patients with severe malaria treated with artesunate is lacking. This retrospective cohort study describes the experience at Hospital Clinic of Barcelona with the use of artesunate for severe malaria and the joint use of RBC exchange in selected cases. Patients treated for severe malaria at Hospital Clinic of Barcelona between August 2013 and January 2015 were included in this retrospective study. Severe malaria was defined according to WHO criteria. Data were extracted from electronic hospital records. A log-linear mixed model approach was used to estimate parasite clearance times. Within the study period, 42 patients were diagnosed of malaria at this centre, of which 38 had Plasmodium falciparum (90.5 %). Sixteen patients (42 %) had severe malaria cases and were treated with intravenous artesunate. Four patients underwent RBC exchange within a period of 15 h after the first dose of artesunate (range 9-21 h). The procedure lasted a median of 2 h (IQR 1.8-2 h), using a median of 12 (IQR 11-14) units of packed RBCs to replace a median of 3794 ml (IQR 2977-4343). The technique was well-tolerated without haemodynamic complications. There were no deaths. The regression model showed an estimated time to 95 % decay of 21.6 h (95 % CI 17.3-28.8). When assessing effect modification by RBC exchange, there was no difference in the parasite elimination rate (p = 0.286). In this study RBC exchange failed to show benefits in terms of parasite clearance probably due to the small number of patients analysed. The evidence for exchange transfusion remains limited.

Beyond the Echo Chamber: Pedagogical Tools for Civic Engagement Discourse and Reflection

ERIC Educational Resources Information Center

Panke, Stefanie; Stephens, John

2018-01-01

How can educators leverage blogs and other social media spaces to encourage a reflective, critical discourse about civic engagement that fosters a true learning exchange over promoting one's own ideas? This article reports upon a single case study of the "Community Engagement Learning Exchange," a multi-author blog on civic engagement.…

Nonlocal gradient corrections to the exchange free energy of an inhomogeneous many-fermion system at finite temperature

NASA Astrophysics Data System (ADS)

Geldart, D. J. W.; Dunlap, E.; Glasser, M. L.; Shegelski, Mark R. A.

1993-10-01

A general exact result is derived for the coefficient B x( n; T) which determines the first gradient correction to the leading exchange contribution to the free energy at finite temperature of a weakly inhomogeneous extended many fermion system having arbitrary two-body interactions. Explicit analytical results are given in the case of bare Coulomb interactions, and the case of statically screened Coulomb interactions is studied numerically. It is shown that nonanalytical structure leads to different limiting values of B x( n; T) when the inverse screening length and the temperature are both small. Some implications for physical many-electron systems are discussed, including the reasons for discrepancies between the first principles and semiempirical gradient coefficients for atomic exchange energies.

Development and application of an exchange model for anisotropic water diffusion in the microporous MOF aluminum fumarate

NASA Astrophysics Data System (ADS)

Splith, Tobias; Fröhlich, Dominik; Henninger, Stefan K.; Stallmach, Frank

2018-06-01

Diffusion of water in aluminum fumarate was studied by means of pulsed field gradient (PFG) nuclear magnetic resonance (NMR). Due to water molecules exchanging between the intracrystalline anisotropic pore space and the isotropic intercrystalline void space the model of intracrystalline anisotropic diffusion fails to describe the experimental PFG NMR data at high observation times. Therefore, the two-site exchange model developed by Kärger is extended to the case of exchange between an anisotropic and an isotropic site. This extended exchange model is solved by numerical integration. It describes the experimental data very well and yields values for the intracrystalline diffusion coefficient and the mean residence times of the respective sites. Further PFG NMR studies were performed with coatings consisting of small aluminum fumarate crystals, which are used in adsorptive heat transformation applications. The diffusion coefficients of water in the small crystal coating are compared to the values expected from the extended two-site exchange model and from the model of long-range diffusion.

Exchange coupling in the complex magnetic multilayers

NASA Astrophysics Data System (ADS)

Uzdin, V. M.; Adamowicz, L.; Kocinski, P.

1996-06-01

Exchange coupling in the complex magnetic sandwich structures containing nonmagnetic (NM) and ferromagnetic (FM) layers composed of two different ferromagnetic metals has been studied within the framework of the quantum wells model. The strength of the exchange coupling in the multilayer structure with thin layers of a second ferromagnetic material inserted at the interface of FM/NM/FM sandwich was calculated at various physical situations. In one case the exponential dependence of the exchange coupling on the thickness of the interface ferromagnetic layer has been obtained in striking resemblance to the Parkin experimental results for magnetoresistance (S. S. P. Parkin, Phys. Rev. Lett., 71 (1993) 1641).

Satisfying patient-consumer principles for health information exchange: evidence from California case studies.

PubMed

Miller, Robert H

2012-03-01

In June 2010 sixteen organizations representing California patients and consumers adopted nine principles for electronically exchanging health information among and within provider organizations. The principles were formulated with the goal of improving patient and population health care by increasing the availability and use of patient data while protecting patients' privacy. This study assesses to what extent five health care organizations-all in different stages of increasing their capacity for health information exchange-conformed to the principles in early 2011. Although an increasing amount of electronic data has been exchanged among organizations and with patients, progress has been modest, and patients still have little control over their data. For organizations to comply with all nine patient and consumer principles, clear "rules of the road" for information sharing must be defined, and patient education in health information exchange and control over personal data must be increased.

Understanding the drivers of interprofessional collaborative practice among HIV primary care providers and case managers in HIV care programmes.

PubMed

Mavronicolas, Heather A; Laraque, Fabienne; Shankar, Arti; Campbell, Claudia

2017-05-01

Care coordination programmes are an important aspect of HIV management whose success depends largely on HIV primary care provider (PCP) and case manager collaboration. Factors influencing collaboration among HIV PCPs and case managers remain to be studied. The study objective was to test an existing theoretical model of interprofessional collaborative practice and determine which factors play the most important role in facilitating collaboration. A self-administered, anonymous mail survey was sent to HIV PCPs and case managers in New York City. An adapted survey instrument elicited information on demographic, contextual, and perceived social exchange (trustworthiness, role specification, and relationship initiation) characteristics. The dependent variable, perceived interprofessional practice, was constructed from a validated scale. A sequential block wise regression model specifying variable entry order examined the relative importance of each group of factors and of individual variables. The analysis showed that social exchange factors were the dominant drivers of collaboration. Relationship initiation was the most important predictor of interprofessional collaboration. Additional influential factors included organisational leadership support of collaboration, practice settings, and frequency of interprofessional meetings. Addressing factors influencing collaboration among providers will help public health programmes optimally design their structural, hiring, and training strategies to foster effective social exchanges and promote collaborative working relationships.

Manual exchange transfusion for severe imported falciparum malaria: a retrospective study.

PubMed

Lin, Jinfeng; Huang, Xiaoying; Qin, Gang; Zhang, Suyan; Sun, Weiwei; Wang, Yadong; Ren, Ke; Xu, Junxian; Han, Xudong

2018-01-16

This study was designed to evaluate the efficacy of exchange transfusion in patients with severe imported falciparum malaria. Twelve patients who met the diagnostic criteria for severe malaria were treated with exchange transfusion 14 times according to a conventional anti-malarial treatment. This study evaluated the efficacy of exchange transfusion for severe imported falciparum malaria. Clinical data of severe imported falciparum malaria patients admitted to the intensive care unit (ICU) of Nantong Third People's Hospital from January 2007 to December 2016 were investigated in this retrospective study. Patients were divided into the intervention group, which received exchange transfusion, and the control group. This study assessed parasite clearance and outcomes of the two groups, and levels of erythrocytes, haemoglobin, platelets, coagulation, liver function, lactate, C-reactive protein, and procalcitonin, before and after exchange transfusion in the intervention group. There was no significant difference in the severity of admitted patients. Exchange transfusion was successfully applied 14 times in the intervention group. Differences in the levels of erythrocytes, haemoglobin and platelets did not reach statistical significance. Exchange transfusion improved coagulation, liver function, lactic acid, C-reactive protein, and procalcitonin. No differences were observed in parasite clearance, ICU and hospital length of stay, in-hospital mortality, and costs of hospitalization between the two groups. Exchange transfusion as adjunctive therapy for severe malaria was observed to be safe in this setting. Exchange transfusion can improve liver function and coagulation and reduce inflammation, but it failed to improve parasite clearance and the outcomes of severe imported falciparum malaria in this case series.

The case of a needle exchange policy debate in Fresno, California

PubMed Central

Clarke, KRIS

2016-01-01

Needle exchange is one of the most effective public health interventions to prevent the transmission of infectious disease by injecting drug users. Despite the preponderance of scientific evidence, US federal funding for needle exchange programmes has been banned since 1988. This prohibition has resulted in the lack of a centralised policy on needle exchange and has given birth to a patchwork of diverse practices and regulations throughout the nation. This article focuses on how various local players interpreted the meaning of needle exchange through the debate on an unauthorised site in Fresno, California. In exploring a specific context, this study delineates the narratives used to outline competing views about needle exchange and to offer a snapshot of how the issue of widespread injecting drug use was handled in an impoverished and socially conservative region of the United States. PMID:28035171

The use of laboratory-determined ion exchange parameters in the predictive modelling of field-scale major cation migration in groundwater over a 40-year period.

PubMed

Carlyle, Harriet F; Tellam, John H; Parker, Karen E

2004-01-01

An attempt has been made to estimate quantitatively cation concentration changes as estuary water invades a Triassic Sandstone aquifer in northwest England. Cation exchange capacities and selectivity coefficients for Na(+), K(+), Ca(2+), and Mg(2+) were measured in the laboratory using standard techniques. Selectivity coefficients were also determined using a method involving optimized back-calculation from flushing experiments, thus permitting better representation of field conditions; in all cases, the Gaines-Thomas/constant cation exchange capacity (CEC) model was found to be a reasonable, though not perfect, first description. The exchange parameters interpreted from the laboratory experiments were used in a one-dimensional reactive transport mixing cell model, and predictions compared with field pumping well data (Cl and hardness spanning a period of around 40 years, and full major ion analyses in approximately 1980). The concentration patterns predicted using Gaines-Thomas exchange with calcite equilibrium were similar to the observed patterns, but the concentrations of the divalent ions were significantly overestimated, as were 1980 sulphate concentrations, and 1980 alkalinity concentrations were underestimated. Including representation of sulphate reduction in the estuarine alluvium failed to replicate 1980 HCO(3) and pH values. However, by including partial CO(2) degassing following sulphate reduction, a process for which there is 34S and 18O evidence from a previous study, a good match for SO(4), HCO(3), and pH was attained. Using this modified estuary water and averaged values from the laboratory ion exchange parameter determinations, good predictions for the field cation data were obtained. It is concluded that the Gaines-Thomas/constant exchange capacity model with averaged parameter values can be used successfully in ion exchange predictions in this aquifer at a regional scale and over extended time scales, despite the numerous assumptions inherent in the approach; this has also been found to be the case in the few other published studies of regional ion exchanging flow.

The use of laboratory-determined ion exchange parameters in the predictive modelling of field-scale major cation migration in groundwater over a 40-year period

NASA Astrophysics Data System (ADS)

Carlyle, Harriet F.; Tellam, John H.; Parker, Karen E.

2004-01-01

An attempt has been made to estimate quantitatively cation concentration changes as estuary water invades a Triassic Sandstone aquifer in northwest England. Cation exchange capacities and selectivity coefficients for Na +, K +, Ca 2+, and Mg 2+ were measured in the laboratory using standard techniques. Selectivity coefficients were also determined using a method involving optimized back-calculation from flushing experiments, thus permitting better representation of field conditions; in all cases, the Gaines-Thomas/constant cation exchange capacity (CEC) model was found to be a reasonable, though not perfect, first description. The exchange parameters interpreted from the laboratory experiments were used in a one-dimensional reactive transport mixing cell model, and predictions compared with field pumping well data (Cl and hardness spanning a period of around 40 years, and full major ion analyses in ˜1980). The concentration patterns predicted using Gaines-Thomas exchange with calcite equilibrium were similar to the observed patterns, but the concentrations of the divalent ions were significantly overestimated, as were 1980 sulphate concentrations, and 1980 alkalinity concentrations were underestimated. Including representation of sulphate reduction in the estuarine alluvium failed to replicate 1980 HCO 3 and pH values. However, by including partial CO 2 degassing following sulphate reduction, a process for which there is 34S and 18O evidence from a previous study, a good match for SO 4, HCO 3, and pH was attained. Using this modified estuary water and averaged values from the laboratory ion exchange parameter determinations, good predictions for the field cation data were obtained. It is concluded that the Gaines-Thomas/constant exchange capacity model with averaged parameter values can be used successfully in ion exchange predictions in this aquifer at a regional scale and over extended time scales, despite the numerous assumptions inherent in the approach; this has also been found to be the case in the few other published studies of regional ion exchanging flow.

Academic and Linguistic Gains during a Semester-Long Study Abroad: A Cohort Case Study

ERIC Educational Resources Information Center

Cai, Wei; Li, Xiangrong; Liu, Meihua

2013-01-01

The present case study investigated university students' academic and linguistic gains during a semester-long exchange program abroad. Thirty three third-year English majors from a Chinese university answered a battery of questionnaires and 13 of them participated in semi-structured interviews both prior to and after the program. Analyses of the…

Investment Matters: Supremacy of English and (Re)construction of Identity in International Exchange

ERIC Educational Resources Information Center

Hashimoto, Hiroko; Kudo, Kazuhiro

2010-01-01

In Japan critical views of the dominance of English are only infrequently voiced, and the use of English is promoted for the benefits associated with it. This paper discusses the issues of language and power in intercultural communication on the basis of a case study on the Ship for World Youth, an intensive "international exchange"…

Toward a Political Economic Theory of Education: Use and Exchange Values of Enhanced Labor Power

ERIC Educational Resources Information Center

Williams, Julian

2011-01-01

I explore theoretical conceptions of the use and exchange values of mathematics education within cultural-historical activity theory perspectives. The case of education in England is compared with that of health care (due to Engestrom). Then I draw on Lave and McDermott's study of estranged learning from the early Marx, and from Marx's later…

Skype-Based English Activities: A Case for Compelling Input? Correlational Changes before and after Skype Exchanges

ERIC Educational Resources Information Center

Ockert, David

2015-01-01

This paper reports the results of a small, longitudinal study involving a group of Japanese elementary school students (N = 29) involved in exploratory research using foreign language activities, including two Skype exchanges between these students and students in Australia. The purpose of the research was to test for the impact of a series of…

Creating Sustainable Cities through Knowledge Exchange: A Case Study of Knowledge Transfer partnerships

ERIC Educational Resources Information Center

Hope, Alex

2016-01-01

Purpose: The purpose of this paper is to examine the use of knowledge transfer partnership (KTP)as a means for universities to generate and exchange knowledge to foster sustainable cities and societies. Design/methodology/approach: This paper reports on a series of separate yet interrelated KTPs between a university and the local authority in the…

Knowledge Exchange between Universities and the Creative Industries in the UK: A Case Study of Current Practice

ERIC Educational Resources Information Center

Ferguson, Morag

2014-01-01

The importance to the economy of knowledge exchange between universities and industry has long been recognized, and in the UK a number of initiatives are in place to support such activities. These initiatives have helped to stimulate engagement between universities and the creative industries, a sector of increasing importance to the UK economy.…

Clinical outcomes and predictive factors related to good outcomes in plasma exchange in severe attack of NMOSD and long extensive transverse myelitis: Case series and review of the literature.

PubMed

Aungsumart, Saharat; Apiwattanakul, Metha

2017-04-01

To investigate the predictive factors associated with good outcomes of plasma exchange in severe attacks through neuromyelitis optica spectrum disorder (NMOSD) and long extensive transverse myelitis (LETM). In addition, to review the literature of predictive factors associated with the good outcomes of plasma exchange in central nervous system inflammatory demyelinating diseases (CNS IDDs). Retrospective study in 27 episodes of severe acute attacks myelitis and optic neuritis in 24 patients, including 20 patients with NMOSD seropositive, 1 patient with NMOSD seronegative and 3 patients with LETM. Plasma exchange was performed, reflecting poor responses to high-dose intravenous methylprednisolone (IVMP) therapy. The outcomes of the present study were the functional outcome improvements at 6 months after plasma exchange. The predictive factors of good outcomes after plasma exchange were determined in this cohort, and additional factors reported in the literature were reviewed. Plasma exchange was performed in 16 spinal cord attacks and 11 attacks of optic neuritis. Twenty patients were female (83%). The median age of the patients at the time of plasma exchange was 41 years old. The median disease duration was 0.6 years. The AQP4-IgG status was positive in 20 patients (83%). Plasma exchange following IVMP therapy led to a significant improvement in 81% of the cases after 6 months of follow up. A baseline Expanded Disability Status Scale (EDSS) score ≤6 before the attack was associated with significant improvement at 6 months (p=0.02, OR 58.33, 95%CI 1.92-1770). In addition, we reviewed the evidence for factors associated with good outcomes of plasma exchange in CNS IDDs, classified according to pre-plasma exchange, post-plasma exchange, and radiological features. Plasma exchange following IVMP therapy is effective as a treatment for patients experiencing a severe attack of NMOSD or LETM. The factors associated with good outcomes after plasma exchange in CNS IDDs are reviewed in the literature. We classified 3 different aspects, including pre-plasma exchange factors, based on minimal disability at baseline, preserved reflexes, early initiation, and short disease duration; post plasma exchange factors, including early improvement or lower disability at last follow up; and radiographic factors, for which the presence of active gadolinium lesions and the absence of spinal cord atrophy seem to be good outcomes for plasmapheresis. Copyright © 2017. Published by Elsevier B.V.

Cooperative Autonomy in Online Lingua Franca Exchanges: A Case Study on Foreign Language Education in Secondary Schools

ERIC Educational Resources Information Center

Hoffstaedter, Petra; Kohn, Kurt

2016-01-01

We report on a case study on pedagogical affordances of intercultural telecollaboration for authentic communication practice and competence development in the local foreign language. Focus is on spoken and written conversations involving pairs of secondary school pupils of different linguacultural backgrounds. Particular attention is given to…

How Macromedia Used Blogs to Build Its Developers' Communities: A Case Study

ERIC Educational Resources Information Center

Cheng, Jingli

2008-01-01

Business organizations are using blogs as a conversational technology to help build a community of practice where knowledge exchange and sharing actively take place. This case study examines how Macromedia used blogs to build its developers' communities and become more organizationally effective. Four major types of interactions between the…

CLOSED-LOOP TREATMENT OF ELECTROLYTIC AND ELECTROLESS NICKEL RINSE WATER BY POINT-OF-USE ION EXCHANGE: A CASE STUDY

EPA Science Inventory

Many recent pilot tests have demonstrated the benefits and cost effectiveness of point-of-use treatment technologies as opposed to centralized wastewater treatment for all sizes of plating facilities. A 9-month case study at a small plating facility in Cincinnati, OH utilizing po...

17 CFR 240.10b5-2 - Duties of trust or confidence in misappropriation insider trading cases.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Duties of trust or confidence... Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) GENERAL RULES AND REGULATIONS, SECURITIES EXCHANGE ACT OF 1934 Rules and Regulations Under the Securities Exchange Act of 1934 Manipulative and Deceptive...

17 CFR 240.10b5-2 - Duties of trust or confidence in misappropriation insider trading cases.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Duties of trust or confidence... Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) GENERAL RULES AND REGULATIONS, SECURITIES EXCHANGE ACT OF 1934 Rules and Regulations Under the Securities Exchange Act of 1934 Manipulative and Deceptive...

17 CFR 240.10b5-2 - Duties of trust or confidence in misappropriation insider trading cases.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 17 Commodity and Securities Exchanges 3 2013-04-01 2013-04-01 false Duties of trust or confidence... Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) GENERAL RULES AND REGULATIONS, SECURITIES EXCHANGE ACT OF 1934 Rules and Regulations Under the Securities Exchange Act of 1934 Manipulative and Deceptive...

17 CFR 240.10b5-2 - Duties of trust or confidence in misappropriation insider trading cases.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 17 Commodity and Securities Exchanges 4 2014-04-01 2014-04-01 false Duties of trust or confidence... Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) GENERAL RULES AND REGULATIONS, SECURITIES EXCHANGE ACT OF 1934 Rules and Regulations Under the Securities Exchange Act of 1934 Manipulative and Deceptive...

17 CFR 240.10b5-2 - Duties of trust or confidence in misappropriation insider trading cases.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 17 Commodity and Securities Exchanges 3 2012-04-01 2012-04-01 false Duties of trust or confidence... Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) GENERAL RULES AND REGULATIONS, SECURITIES EXCHANGE ACT OF 1934 Rules and Regulations Under the Securities Exchange Act of 1934 Manipulative and Deceptive...

X-ray Magnetosheath Emission from Solar Wind Charge Exchange During Two CME Events in 2001

NASA Astrophysics Data System (ADS)

Sembay, S.; Whittaker, I. C.; Read, A.; Carter, J. A.; Milan, S. E.; Palmroth, M.

2016-12-01

Using a combination of the GUMICS-4 MHD model and observed solar wind heavy ion abundances from ACE, we produce case studies looking at X-ray emission from charge exchange in the Earth's magnetosheath. We specifically look in the 0.5-0.7 keV range, which is dominated by highly ionised oxygen emission. Previous studies looking at solar wind charge exchange (SWCX) emission have verified our modelling process via comparison to the XMM-Newton X-ray observatory, and we use the same simulation process here. This study investigates the emission magnitude changes that occur during two coronal mass ejection (CME) events (31 March 2001 and 21 October 2001). As part of this work we also provide a novel masking technique to exclude the plasma of terrestrial origin in the MHD model. As expected the two CME cases examined provide an increased dynamic pressure which pushes the magnetopause closer to the Earth, with a high temporal variation. We show how these changes cause an increase in the peak SWCX emission signature by over an order of magnitude from the quiescent solar wind case. Imaging of this SWCX emission allows a global view of the magnetopause shape and position, a technique planned for future missions such as SMILE (Solar wind Magnetosphere Ionosphere Link Explorer).

17 CFR 270.2a-1 - Valuation of portfolio securities in special cases.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Valuation of portfolio securities in special cases. 270.2a-1 Section 270.2a-1 Commodity and Securities Exchanges SECURITIES AND... of portfolio securities in special cases. (a) Any investment company whose securities are qualified...

Aftershocks following crash of currency exchange rate: The case of RUB/USD in 2014

NASA Astrophysics Data System (ADS)

Usmanova, Vasilya; Lysogorskiy, Yury V.; Abe, Sumiyoshi

2018-02-01

The dynamical behavior of the currency exchange rate after its large-scale catastrophe is discussed through a case study of the rate of Russian rubles to US dollars after its crash in 2014. It is shown that, similarly to the case of the stock market crash, the relaxation is characterized by a power law, which is in analogy with the Omori-Utsu law for earthquake aftershocks. The waiting-time distribution is found to also obey a power law. Furthermore, the event-event correlation is discussed, and the aging phenomenon and scaling property are observed. Comments are made on (non-)Markovianity of the aftershock process and on a possible relevance of glassy dynamics to the market system after the crash.

Geology and evolution of lakes in north-central Florida

USGS Publications Warehouse

Kindinger, J.L.; Davis, J.B.; Flocks, J.G.

1999-01-01

Fluid exchange between surficial waters and groundwater in karst environments, and the processes that control exchange, are of critical concern to water management districts and planners. High-resolution seismic data were collected from 30 lakes of north-central Florida. In each case study, lake structure and geomorphology were controlled by solution and/or mechanical processes. Processes that control lake development are twofold: (1) karstification or dissolution of the underlying limestone, and (2) the collapse, subsidence, or slumping of overburden to form sinkholes. Initial lake formation is directly related to the karst topography of the underlying host limestone. Case studies have shown that lakes can be divided by geomorphic types into progressive developmental phases: (1) active subsidence or collapse phase (young); (2) transitional phase (middle age); (3) baselevel phase (mature); and (4) polje (drowned prairie) - broad flat-bottom that have one or all phases of sinkhole. Using these criteria, Florida lakes can be classified by size, fill, subsurface features, and geomorphology.Fluid exchange between surficial waters and groundwater in karst environments, and the processes that control exchange, are of critical concern to water management districts and planners. High-resolution seismic data were collected from 30 lakes of north-central Florida. In each case study, lake structure and geomorphology were controlled by solution and/or mechanical processes. Processes that control lake development are twofold: (1) karstification or dissolution of the underlying limestone, and (2) the collapse, subsidence, or slumping of overburden to form sinkholes. Initial lake formation is directly related to the karst topography of the underlying host limestone. Case studies have shown that lakes can be divided by geomorphic types into progressive developmental phased: (1) active subsidence or collapse phase (young); (2) transitional phase (middle age); (3) baselevel phase (mature); and (4) polje (drowned prairie) - broad flat-bottom that have one or all phases of sinkhole. Using these criteria, Florida lakes can be classified by size, fill, subsurface features, and geomorphology.

Management of sulcus-fixated single-piece intraocular lens-induced pigmentary glaucoma with 3-piece IOL exchange.

PubMed

Rabie, Hossein Mohammad; Esfandiari, Hamed; Rikhtegar, Mohammad Hassan; Hekmat, Vahid

2018-02-01

To describe our experience with exchanging sulcus-fixated single-piece intraocular lens (IOL) with 3-piece IOLs for management of pigmentary glaucoma. In this retrospective study, records of patients who underwent sulcus-fixated single-piece IOL exchanged with 3-piece IOLs were retrieved, and demographic and baseline data of patients, type of IOL, pre- and post-IOL exchange BCVA, IOP, number of anti-glaucoma medications, and optic nerve head examination were documented. Baseline and final examinations were analyzed and compared. Mean age of the patients was 59 ± 10 years, and 5 (41.6%) were female. Mean interval between primary cataract extraction operation and IOL exchange was 17 ± 5 months. Nine patients received in sulcus implantation of Alcon SA60AT, and three patients had SN60WF model at the end of primary surgery. BCVA changed insignificantly from 0.06 ± 0.06 logMAR to 0.06 ± 0.06 after IOL exchange. (P = 0.22) IOP was controlled in 8 cases (66.6%), but four cases (33.3%) needed glaucoma surgery to further control glaucoma condition. IOP decreased significantly from preoperative 17 ± 3 to 14 ± 1 mmHg postoperatively. Patients with advanced age and higher baseline IOP were more likely to undergo glaucoma surgery after IOL exchange. (P = 0.07 and 0.00, respectively). single-piece IOL exchange with 3-piece IOL dramatically decreases pigment release and reduces IOP. Those with advanced age and higher IOP are less likely to respond to IOL exchange and may need glaucoma surgery to control high intraocular pressure.

Acetone and Water on TiO₂(110): H/D Exchange

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henderson, Michael A.

2005-04-12

Isotopic H/D exchange between coadsorbed acetone and water on the TiO?(110) surface was examined using temperature programmed desorption (TPD) as a function of coverage and two surface pretreatments (oxidation and reduction). Coadsorbed acetone and water interact repulsively on reduced TiO?(110) based on results from the companion paper to this study, with water exerting a greater influence in destabilizing acetone and acetone having only a nominal influence on water. Despite the repulsive interaction between these coadsorbates, about 0.02 ML of a 1 ML d6-acetone on the reduced surface exhibits H/D exchange with coadsorbed water, with the exchange occurring exclusively in themore » high temperature region of the d?-acetone TPD spectrum at {approx}340 K. The effect was confirmed with combinations of d?-acetone and D?O. The extent of exchange decreased on the reduced surface with water coverages above {approx}0.3 ML due to the ability of water to displace coadsorbed acetone from first layer sites to the multilayer. In contrast, the extent of exchange increased by a factor of 3 when the surface was pre-oxidized prior to coadsorption. In this case, there was no evidence for the negative influence of high water coverages on the extent of H/D exchange. Comparison of the TPD spectra from the exchange products (either d?- or d?-acetone depending on the coadsorption pairing) suggests that, in addition to the 340 K exchange process seen on the reduced surface, a second exchange process was observed on the oxidized surface at {approx}390 K. In both cases (oxidized and reduced), desorption of the H/D exchange products appeared to be reaction limited and to involve the influence of OH/OD groups (or water formed during recombinative desorption of OH/OD groups) instead of molecularly adsorbed water. The 340 K exchange process is assigned to reaction at step sites and the 390 K exchange process is attributed to the influence of oxygen adatoms deposited during surface oxidation. The H/D exchange mechanism likely involves an enolate or propenol surface intermediate formed transiently during the desorption of oxygen-stabilized acetone molecules.« less

Building America Case Study: Simplified Air Distribution, Desuperheaters, and Sub-Slab Geothermal Heat Exchangers, Pittsburgh, Pennsylvania

DOE Office of Scientific and Technical Information (OSTI.GOV)

This report presents a cold-climate project that examines an alternative approach to ground source heat pump (GSHP) ground loop design. The innovative ground loop design is an attempt to reduce the installed cost of the ground loop heat exchange portion of the system by containing the entire ground loop within the excavated location beneath the basement slab.

The Contribution of Email Exchanges to Second Language Acquisition: A Case of Cross-Cultural Communication between Africa and North America

ERIC Educational Resources Information Center

Ndemanu, Michael Takafor

2012-01-01

An online epistolary project was conducted with Cameroonian French-speaking students in order to boost English language learning. The project involved email exchanges (in English) between a small group of students from Cameroon and Canada, and it was coordinated by their teachers in both countries. At the end of the study, student emails were…

Secondary Heat Exchanger Design and Comparison for Advanced High Temperature Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piyush Sabharwall; Ali Siahpush; Michael McKellar

2012-06-01

The goals of next generation nuclear reactors, such as the high temperature gas-cooled reactor and advance high temperature reactor (AHTR), are to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. The need for efficiency, compactness, and safety challenge the boundaries of existing heat exchanger technology, giving rise to the following study. Various studies have been performed in attempts to update the secondarymore » heat exchanger that is downstream of the primary heat exchanger, mostly because its performance is strongly tied to the ability to employ more efficient conversion cycles, such as the Rankine super critical and subcritical cycles. This study considers two different types of heat exchangers—helical coiled heat exchanger and printed circuit heat exchanger—as possible options for the AHTR secondary heat exchangers with the following three different options: (1) A single heat exchanger transfers all the heat (3,400 MW(t)) from the intermediate heat transfer loop to the power conversion system or process plants; (2) Two heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants, each exchanger transfers 1,700 MW(t) with a parallel configuration; and (3) Three heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants. Each heat exchanger transfers 1,130 MW(t) with a parallel configuration. A preliminary cost comparison will be provided for all different cases along with challenges and recommendations.« less

[Determination of soil exchangeable base cations by using atomic absorption spectrophotometer and extraction with ammonium acetate].

PubMed

Zhang, Yu-ge; Xiao, Min; Dong, Yi-hua; Jiang, Yong

2012-08-01

A method to determine soil exchangeable calcium (Ca), magnesium (Mg), potassium (K), and sodium (Na) by using atomic absorption spectrophotometer (AAS) and extraction with ammonium acetate was developed. Results showed that the accuracy of exchangeable base cation data with AAS method fits well with the national standard referential soil data. The relative errors for parallel samples of exchangeable Ca and Mg with 66 pair samples ranged from 0.02%-3.14% and 0.06%-4.06%, and averaged to be 1.22% and 1.25%, respectively. The relative errors for exchangeable K and Na with AAS and flame photometer (FP) ranged from 0.06%-8.39% and 0.06-1.54, and averaged to be 3.72% and 0.56%, respectively. A case study showed that the determination method for exchangeable base cations by using AAS was proven to be reliable and trustable, which could reflect the real situation of soil cation exchange properties in farmlands.

Creating an Institutional Identity out of "Differences": A Case Study of Multicultural Organizational Change.

ERIC Educational Resources Information Center

Bensimon, Estela Mara

This case study examines the efforts of one small private liberal arts college to exchange a monocultural organizational structure for one that is grounded in the racial, ethnic, and cultural diversity of the student body. The paper is based on interviews with faculty, administrators, students, and trustees and provides a detailed description of…

76 FR 10353 - Locational Exchanges of Wholesale Electric Power

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-24

... Exchanges of Wholesale Electric Power AGENCY: Federal Energy Regulatory Commission. ACTION: Notice of... Commission in providing guidance as to the circumstances under which locational exchanges of electric power... exchanges of electric power should be permitted generically or considered by the Commission on a case-by...

Glauber exchange amplitudes. [electron scattering from H atoms

NASA Technical Reports Server (NTRS)

Madan, R. N.

1975-01-01

The extrapolation method of Ochkur, valid for intermediate energies (about 50 eV), is applied to the exchange form of the Glauber amplitudes. In the case of elastic scattering of electrons from hydrogen atoms at 54.4 Ev the 'post' and 'prior' forms of the exchange amplitude are equivalent, whereas for the case of inelastic scattering there is a minute discrepancy between the two forms of the amplitude. The results are compared with the close-coupling calculation. The investigation is expected to be useful for optically forbidden exchange-allowed transitions due to electron impact at intermediate energies.

Elucidating the mechanisms of paternal non-disjunction of chromosome 21 in humans.

PubMed

Savage, A R; Petersen, M B; Pettay, D; Taft, L; Allran, K; Freeman, S B; Karadima, G; Avramopoulos, D; Torfs, C; Mikkelsen, M; Hassold, T J; Sherman, S L

1998-08-01

Paternal non-disjunction of chromosome 21 accounts for 5-10% of Down syndrome cases, therefore, relative to the maternally derived cases, little is known about paternally derived trisomy 21. We present the first analysis of recombination and non-disjunction for a large paternally derived population of free trisomy 21 conceptuses ( n = 67). Unlike maternal cases where the ratio of meiosis I (MI) to meiosis II (MII) errors is 3:1, a near 1:1 ratio exists among paternal cases, with a slight excess of MII errors. We found no paternal age effect for the overall population nor when classifying cases according to stage of non-disjunction error. Among 22 MI cases, only five had an observable recombinant event. This differs significantly from the 11 expected events ( P < 0.02, Fisher's exact), suggesting reduced recombination along the non-disjoined chromosomes 21 involved in paternal MI non-disjunction. No difference in recombination was detected among 27 paternal MII cases as compared with controls. However, cases exhibited a slight increase in the frequency of proximal and medial exchange when compared with controls (0.37 versus 0.28, respectively). Lastly, this study confirmed previous reports of excess male probands among paternally derived trisomy 21 cases. However, we report evidence suggesting an MII stage-specific sex ratio disturbance where 2.5 male probands were found for each female proband. Classification of MII cases based on the position of the exchange event suggested that the proband sex ratio disturbance was restricted to non-telomeric exchange cases. Based on these findings, we propose new models to explain the association between paternally derived trisomy 21 and excessive male probands.

Scaling Exponents in Financial Markets

NASA Astrophysics Data System (ADS)

Kim, Kyungsik; Kim, Cheol-Hyun; Kim, Soo Yong

2007-03-01

We study the dynamical behavior of four exchange rates in foreign exchange markets. A detrended fluctuation analysis (DFA) is applied to detect the long-range correlation embedded in the non-stationary time series. It is for our case found that there exists a persistent long-range correlation in volatilities, which implies the deviation from the efficient market hypothesis. Particularly, the crossover is shown to exist in the scaling behaviors of the volatilities.

Mutually catalyzed birth of population and assets in exchange-driven growth

NASA Astrophysics Data System (ADS)

Lin, Zhenquan; Ke, Jianhong; Ye, Gaoxiang

2006-10-01

We propose an exchange-driven aggregation growth model of population and assets with mutually catalyzed birth to study the interaction between the population and assets in their exchange-driven processes. In this model, monomer (or equivalently, individual) exchange occurs between any pair of aggregates of the same species (population or assets). The rate kernels of the exchanges of population and assets are K(k,l)=Kkl and L(k,l)=Lkl , respectively, at which one monomer migrates from an aggregate of size k to another of size l . Meanwhile, an aggregate of one species can yield a new monomer by the catalysis of an arbitrary aggregate of the other species. The rate kernel of asset-catalyzed population birth is I(k,l)=Iklμ [and that of population-catalyzed asset birth is J(k,l)=Jklν ], at which an aggregate of size k gains a monomer birth when it meets a catalyst aggregate of size l . The kinetic behaviors of the population and asset aggregates are solved based on the rate equations. The evolution of the aggregate size distributions of population and assets is found to fall into one of three categories for different parameters μ and ν : (i) population (asset) aggregates evolve according to the conventional scaling form in the case of μ⩽0 (ν⩽0) , (ii) population (asset) aggregates evolve according to a modified scaling form in the case of ν=0 and μ>0 ( μ=0 and ν>0 ), and (iii) both population and asset aggregates undergo gelation transitions at a finite time in the case of μ=ν>0 .

Tax Implications of Forest Property Exchanges

Treesearch

William C. Siegel

1999-01-01

For various reasons, it may be advantageous for woodland owners to voluntarily exchange some or all of their timber and/or timberland for other property. For example, exchanges can be used to consolidate or diversify forest holdings and other investments; to obtain greater cash flow; and eliminate or reduce management problems. In many cases, voluntary exchanges--...

Overall heat transfer coefficient and pressure drop in a typical tubular exchanger employing alumina nano-fluid as the tube side hot fluid

NASA Astrophysics Data System (ADS)

Kabeel, A. E.; Abdelgaied, Mohamed

2016-08-01

Nano-fluids are used to improve the heat transfer rates in heat exchangers, especially; the shell-and-tube heat exchanger that is considered one of the most important types of heat exchangers. In the present study, an experimental loop is constructed to study the thermal characteristics of the shell-and-tube heat exchanger; at different concentrations of Al2O3 nonmetallic particles (0.0, 2, 4, and 6 %). This material concentrations is by volume concentrations in pure water as a base fluid. The effects of nano-fluid concentrations on the performance of shell and tube heat exchanger have been conducted based on the overall heat transfer coefficient, the friction factor, the pressure drop in tube side, and the entropy generation rate. The experimental results show that; the highest heat transfer coefficient is obtained at a nano-fluid concentration of 4 % of the shell side. In shell side the maximum percentage increase in the overall heat transfer coefficient has reached 29.8 % for a nano-fluid concentration of 4 %, relative to the case of the base fluid (water) at the same tube side Reynolds number. However; in the tube side the maximum relative increase in pressure drop has recorded the values of 12, 28 and 48 % for a nano-material concentration of 2, 4 and 6 %, respectively, relative to the case without nano-fluid, at an approximate value of 56,000 for Reynolds number. The entropy generation reduces with increasing the nonmetallic particle volume fraction of the same flow rates. For increase the nonmetallic particle volume fraction from 0.0 to 6 % the rate of entropy generation decrease by 10 %.

Therapeutic plasma exchange in poisoning: 8 years' experience of a university hospital.

PubMed

Dişel, Nezihat Rana; Akpınar, Ayça Açıkalın; Sebe, Ahmet; Karakoç, Emre; Sürer, Selen; Turhan, Ferda Tekin; Matyar, Selçuk

2015-10-01

This study examined the extracorporeal methods for the elimination of toxic substances in poisoned patients that are used by clinicians taking care of such patients. Here we present our experience in the use of therapeutic plasma exchange (TPE). To the best of our knowledge, this is the largest number of poisoning cases ever reported in a study. This is a retrospective study conducted at the Çukurova University Faculty of Medicine, Department of Emergency Medicine, with the permission of the ethical committee of the medical faculty. The study includes patients who had undergone TPE because of poisoning between January 2007 and May 2015. We summarize the clinical data and outcomes of the patients with available files. A total of 36 cases among the 42 patients who underwent TPE in this 8-year period were included in the study. More than 20 identified toxic substances, most of which were pesticides, were found to be the causes of poisoning. Twenty-three healthy discharges and 12 deaths are discussed in the study. We believe that our study reports the largest ever number of poisoning cases treated with TPE in the literature. When applicable, TPE may be a promising extracorporeal elimination and treatment technique in poisoned patients when performed in selected cases. Copyright © 2015 Elsevier Inc. All rights reserved.

The results of therapeutic plasma exchange in patients with severe hyperthyroidism: a retrospective multicenter study.

PubMed

Keklik, Muzaffer; Kaynar, Leylagul; Yilmaz, Mehmet; Sivgin, Serdar; Solmaz, Musa; Pala, Cigdem; Aribas, Sulbiye; Akyol, Gulsah; Unluhizarci, Kursat; Cetin, Mustafa; Eser, Bulent; Unal, Ali

2013-06-01

Hyperthyroidism characterized by elevated serum levels of circulating thyroid hormones. The aim of hyperthyroidism treatment is to achieve a euthyroid state as soon as possible and to maintain euthyroid status. However, drug withdrawal and utilization of alternative therapies are needed in cases in which leucopenia or impairment in liver functions is observed during medical therapy. In the present study, we aimed to present our cases which underwent therapeutic plasma exchange (TPE) due to severe hyperthyroidism. The results of 22 patients who underwent therapeutic plasma exchange due to hyperthyroidism in Apheresis Units of Erciyes University and Gaziantep University, between 2006 and 2012, were retrospectively reviewed. These cases had severe thyrotoxic values despite anti-thyroid drug use. After TPE, we observed a significant decrease in free thyroxin (FT4) (p<0.001) and free triiodotyhronin (FT3) (p<0.004) levels. There was statistically significant increase in the mean values of TSH levels after TPE (p<0.001). Clinical improvement was achieved in hyperthyroidism by TPE in 20 cases (91%). Both FT3 and FT4 levels remained above the normal limits in two of 22 patients. TPE should be considered as an effective and safe therapeutic option to achieve euthyroid state before surgery or radioactive iodine treatment. TPE is a useful option in cases with severe hyperthyroidism unresponsive to anti-thyroid agents and in those with clinical manifestations of cardiac failure and in patients with severe adverse events during anti-thyroid therapy. Copyright © 2013 Elsevier Ltd. All rights reserved.

Extended cooperation in clinical studies through exchange of CDISC metadata between different study software solutions.

PubMed

Kuchinke, W; Wiegelmann, S; Verplancke, P; Ohmann, C

2006-01-01

Our objectives were to analyze the possibility of an exchange of an entire clinical study between two different and independent study software solutions. The question addressed was whether a software-independent transfer of study metadata can be performed without programming efforts and with software routinely used for clinical research. Study metadata was transferred with ODM standard (CDISC). Study software systems employed were MACRO (InferMed) and XTrial (XClinical). For the Proof of Concept, a test study was created with MACRO and exported as ODM. For modification and validation of the ODM export file XML-Spy (Altova) and ODM-Checker (XML4Pharma) were used. Through exchange of a complete clinical study between two different study software solutions, a Proof of Concept of the technical feasibility of a system-independent metadata exchange was conducted successfully. The interchange of study metadata between two different systems at different centers was performed with minimal expenditure. A small number of mistakes had to be corrected in order to generate a syntactically correct ODM file and a "vendor extension" had to be inserted. After these modifications, XTrial exhibited the study, including all data fields, correctly. However, the optical appearance of both CRFs (case report forms) was different. ODM can be used as an exchange format for clinical studies between different study software. Thus, new forms of cooperation through exchange of metadata seem possible, for example the joint creation of electronic study protocols or CRFs at different research centers. Although the ODM standard represents a clinical study completely, it contains no information about the representation of data fields in CRFs.

Back-exchange: a novel approach to quantifying oxygen diffusion and surface exchange in ambient atmospheres.

PubMed

Cooper, Samuel J; Niania, Mathew; Hoffmann, Franca; Kilner, John A

2017-05-17

A novel two-step Isotopic Exchange (IE) technique has been developed to investigate the influence of oxygen containing components of ambient air (such as H 2 O and CO 2 ) on the effective surface exchange coefficient (k*) of a common mixed ionic electronic conductor material. The two step 'back-exchange' technique was used to introduce a tracer diffusion profile, which was subsequently measured using Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS). The isotopic fraction of oxygen in a dense sample as a function of distance from the surface, before and after the second exchange step, could then be used to determine the surface exchange coefficient in each atmosphere. A new analytical solution was found to the diffusion equation in a semi-infinite domain with a variable surface exchange boundary, for the special case where D* and k* are constant for all exchange steps. This solution validated the results of a numerical, Crank-Nicolson type finite-difference simulation, which was used to extract the parameters from the experimental data. When modelling electrodes, D* and k* are important input parameters, which significantly impact performance. In this study La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ (LSCF6428) was investigated and it was found that the rate of exchange was increased by around 250% in ambient air compared to high purity oxygen at the same pO 2 . The three experiments performed in this study were used to validate the back-exchange approach and show its utility.

Linearized finite-element method solution of the ion-exchange nonlinear diffusion model

NASA Astrophysics Data System (ADS)

Badr, Mohamed M.; Swillam, Mohamed A.

2017-04-01

Ion-exchange process is one of the most common techniques used in glass waveguide fabrication. This has many advantages, such as low cost, ease of implementation, and simple equipment requirements. The technology is based on the substitution of some of the host ions in the glass (typically Na+) with other ions that possess different characteristics in terms of size and polarizability. The newly diffused ions produce a region with a relatively higher refractive index in which the light could be guided. A critical issue arises when it comes to designing such waveguides, which is carefully and precisely determining the resultant index profile. This task has been proven to be hideous as the process is generally governed by a nonlinear diffusion model with no direct general analytical solution. Furthermore, numerical solutions become unreliable-in terms of stability and mean squared error-in some cases, especially the K+-Na+ ion-exchanged waveguide, which is the best candidate to produce waveguides with refractive index differences compatible with those of the commercially available optical fibers. Linearized finite-element method formulations were used to provide a reliable tool that could solve the nonlinear diffusion model of the ion-exchange in both one- and two-dimensional spaces. Additionally, the annealed channel waveguide case has been studied. In all cases, unprecedented stability and minimum mean squared error could be achieved.

24 CFR 3280.702 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-04-01

... (in the case of a heat pump) heating system which includes the refrigerant pump (compressor) and the external heat exchanger. Air conditioning evaporator section means a heat exchanger used to cool or (in the case of a heat pump) heat air for use in comfort cooling (or heating) the living space. Air...

24 CFR 3280.702 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-04-01

... (in the case of a heat pump) heating system which includes the refrigerant pump (compressor) and the external heat exchanger. Air conditioning evaporator section means a heat exchanger used to cool or (in the case of a heat pump) heat air for use in comfort cooling (or heating) the living space. Air...

24 CFR 3280.702 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... means that portion of a refrigerated air cooling or (in the case of a heat pump) heating system which includes the refrigerant pump (compressor) and the external heat exchanger. Air conditioning evaporator section means a heat exchanger used to cool or (in the case of a heat pump) heat air for use in comfort...

Augmentation plating in management of failed femoral nailing.

PubMed

Verma, Rahul; Sharma, Pulak; Gaur, Sanjiv

2017-08-01

Non-union following interlocking nailing is a troubling complication in treatment of shaft femur fractures. There is no clear consensus on the treatment of this problem. This research was undertaken to study the role of augmentation plating combined with exchange nailing in such cases. A prospective clinical study was undertaken from January 2010 to December 2015. Patients with aseptic femoral shaft non-union, with or without implant failure following intramedullary nailing were included in the study. Augmentation plating combined with Exchange Nailing with a 4.5mm LCP was done. Fifteen patients (nine male and six female) with an average age of 43.7 years (range 18-67 years) were treated. Average timing from the first surgery was 7.3 months. Complete clinical and radiological union was achieved in all cases in a mean duration of 5.2 months. Average duration of follow up was 12.6 months. All the patients retained the preoperative hip and knee range of motion till the last follow up. Augmentation plating combined with exchange nailing in non-unions following intramedullary nailing of femur shaft fractures is a reasonably good and effective procedure with a very high success rate. © 2017 Elsevier Ltd. All rights reserved.

Cooperation of Horizontal Ground Heat Exchanger with the Ventilation Unit During Summer - Case Study

NASA Astrophysics Data System (ADS)

Romańska-Zapała, Anna; Furtak, Marcin; Dechnik, Mirosław

2017-10-01

Renewable energy sources are used in the modern energy-efficient buildings to improve their energy balance. One of them is used in the mechanical ventilation system ground air heat exchanger (earth-air heat exchanger - EAHX). This solution, right after heat recovery from exhaust air (recuperation), allows the reduction in the energy needed to obtain the desired temperature of supply air. The article presents the results of "in situ" measurements of pipe ground air heat exchanger cooperating with the air handling unit, supporting cooling the building in the summer season, in Polish climatic conditions. The laboratory consists of a ventilation unit intake - exhaust with rotor for which the source of fresh air is the air intake wall and two air intakes field cooperating with the tube with ground air heat exchangers. Selection of the source of fresh air is performed using sprocket with actuators. This system is part of the ventilation system of the Malopolska Laboratory of Energy-Efficient Building (MLBE) building of Cracow University of Technology. The measuring system are, among others, the sensors of parameters of air inlets and outlets of the heat exchanger channels EAHX and weather station that senses the local weather conditions. The measurement data are recorded and archived by the integrated process control system in the building of MLBE. During the study measurements of operating parameters of the ventilation unit cooperating with the selected source of fresh air were performed. Two cases of operation of the system: using EAHX heat exchanger and without it, were analyzed. Potentially the use of ground air heat exchanger in the mechanical ventilation system can reduce the energy demand for heating or cooling rooms by the pre-adjustment of the supply air temperature. Considering the results can be concluded that the continuous use of these exchangers is not optimal. This relationship is appropriate not only on an annual basis for the transitional periods (spring and autumn), but also in individual days in the potentially most favorable periods of work exchanger (summer and winter). Inappropriate operation of the heat exchanger, will lead to a temporary increase in energy consumption for the preparation of the desired air temperature, relative to the fresh air unit which is non-pretreated. For optimal energy system operation: exchanger EAHX - air handling unit, to preserve the most favourable parameters of inlet air to handling unit, there is a need to dynamically adjust the source of fresh air, depending on changing external conditions and the required outlet temperature of central unit (temperature of air forced to the rooms).

Single-step controlled-NOT logic from any exchange interaction

NASA Astrophysics Data System (ADS)

Galiautdinov, Andrei

2007-11-01

A self-contained approach to studying the unitary evolution of coupled qubits is introduced, capable of addressing a variety of physical systems described by exchange Hamiltonians containing Rabi terms. The method automatically determines both the Weyl chamber steering trajectory and the accompanying local rotations. Particular attention is paid to the case of anisotropic exchange with tracking controls, which is solved analytically. It is shown that, if computational subspace is well isolated, any exchange interaction can always generate high fidelity, single-step controlled-NOT (CNOT) logic, provided that both qubits can be individually manipulated. The results are then applied to superconducting qubit architectures, for which several CNOT gate implementations are identified. The paper concludes with consideration of two CNOT gate designs having high efficiency and operating with no significant leakage to higher-lying noncomputational states.

Exchange bias and perpendicular anisotropy study of ultrathin Pt-Co-Pt-IrMn multilayers sputtered on float glass

NASA Astrophysics Data System (ADS)

Laval, M.; Lüders, U.; Bobo, J. F.

2007-09-01

We have prepared ultrathin Pt-Co-Pt-IrMn polycrystalline multilayers on float-glass substrates by DC magnetron sputtering. We have determined the optimal set of thickness for both Pt layers, the Co layer and the IrMn biasing layer so that these samples exhibit at the same time out-of-plane magnetic anisotropy and exchange bias. Kerr microscopy domain structure imaging evidences an increase of nucleation rate accompanied with inhomogeneous magnetic behavior in the case of exchange-biased films compared to Pt-Co-Pt trilayers. Polar hysteresis loops are measured in obliquely applied magnetic field conditions, allowing us to determine both perpendicular anisotropy effective constant Keff and exchange-bias coupling JE, which are significantly different from the ones determined by standard switching field measurements.

Observations of Convective and Dynamical Instabilities in Tropopause Folds and their Contribution to Stratosphere-Troposphere Exchange

NASA Technical Reports Server (NTRS)

Cho, John Y. N.; Newell, Reginald E.; Bui, T. Paul; Browell, Edward V.; Fenn, Martha A.; Gary, Bruce L.; Mahoney, Michael J.; Gregory, Gerald L.; Sachse, Glen W.; Vay, Stephanie A.

1999-01-01

With aircraft-mounted in-situ and remote sensing instruments for dynamical, thermal. and chemical measurements, we studied two cases of tropopause folding. In both folds we found Kelvin-Helmholtz billows with horizontal wavelength of about 900 m and thickness of about 120 m. In one case the instability was effectively mixing the bottomside of the fold, leading to the transfer of stratospheric air into the troposphere. Also we discovered in both cases small-scale secondary ozone maxima shortly after the aircraft ascended past the topside of the fold that corresponded to regions of convective instability. We interpreted this phenomenon as convectively breaking gravity waves. Therefore, we posit that convectively breaking gravity waves acting on tropopause folds must be added to the list of important irreversible mixing mechanisms leading to stratosphere-troposphere exchange.

Complex Heat Exchangers for Improved Performance

NASA Astrophysics Data System (ADS)

Bran, Gabriela Alejandra

After a detailed literature review, it was determined that there was a need for a more comprehensive study on the transient behavior of heat exchangers. Computational power was not readily available when most of the work on transient heat exchangers was done (1956 - 1986), so most of these solutions have restrictions, or very specific assumptions. More recently, authors have obtained numerical solutions for more general problems (2003 - 2013), but they have investigated very specific conditions, and cases. For a more complex heat exchanger (i.e. with heat generation), the transient solutions from literature are no longer valid. There was a need to develop a numerical model that relaxes the restrictions of current solutions to explore conditions that have not been explored. A one dimensional transient heat exchanger model was developed. There are no restrictions on the fluids and wall conditions. The model is able to obtain a numerical solution for a wide range of fluid properties and mass flow rates. Another innovative characteristic of the numerical model is that the boundary and initial conditions are not limited to constant values. The boundary conditions can be a function of time (i.e. sinusoidal signal), and the initial conditions can be a function of position. Four different cases were explored in this work. In the first case, the start-up of a system was investigated where the whole system is assumed to be at the same temperature. In the second case, the new steady state in case one gets disrupted by a smaller inlet temperature step change. In the third case, the new steady state in case one gets disrupted by a step change in one of the mass flow rates. The response of these three cases show that there are different transient behaviors, and they depend on the conditions imposed on the system. The fourth case is a system that has a sinusoidal time varying inlet temperature for one of the flows. The results show that the sinusoidal behavior at the inlet propagates along the channel. However, the sinusoidal behavior on one of the fluids does not fully translate to the other gets damped by the wall and the heat transfer coefficients that can be barely seen on the other flow. A scaling analysis and a parametric study were performed to determine the influence the different parameters on the system have on the time a heat exchanger takes to reach steady state. The results show the dependency of tst* (time a system takes to reach steady state) on the dimensionless parameters M, C, NTUh, NTUc, and Cw. t st* depends linearly on C and Cw, and it is a power function of M. It was also shown that tst* has a logarithmic dependency on NTUh and NTUc. A correlation was generated to approximate the time a system takes to reach steady state for systems where C w << 1. A more complex heat exchanger with the specific application of solar energy storage was also investigated. This application involves a counter-flow heat exchanger with a reacting flow in one of the channels, and it includes varying properties, heat generation, varying heat transfer coefficient, and axial conduction. The application for this reactor heat exchanger is on solar energy storage, and the goals is to heat up steam to 650 °C by using the ammonia synthesis heat of reaction. One of the concerns for this system is the start-up time and also how disturbances in reacting flow can affect the steam outlet temperature. The transient behavior during the system start-up was presented. In order to achieve the desired outlet steam temperature at a reasonable time, the system must operate at high gas mass flow rates. If the inlet temperature of the gas suffers a step change, it affects the reaction rate as well as the outlet steam temperature. A small perturbation on the gas mass flow rate has an effect on the profile shape. However, the maximum temperature reached by the gas due to reaction is not affected, and consequently, it has little effect on the steam temperature. Axial conduction in the reactor heat exchanger was also investigated, specifically in the gas section. Axial conduction cannot be assumed to be negligible in the reactor heat exchanger because of the iron-based catalytic bed. Results in this section show that axial conduction is detrimental for the system. It was found that for Peclet number greater than 100, axial conduction can be neglected. An alternative solution to address axial conduction was proposed, namely to include a well-insulated non-reacting section (without a catalytic bed) upstream of the reactor. The modified reactor heat exchanger was a novel solution to avoid the negative effect of axial conduction. Results show that by having a non-reacting section, axial conduction becomes unimportant.

Laboratory simulation of heat exchange for liquids with Pr > 1: Heat transfer

NASA Astrophysics Data System (ADS)

Belyaev, I. A.; Zakharova, O. D.; Krasnoshchekova, T. E.; Sviridov, V. G.; Sukomel, L. A.

2016-02-01

Liquid metals are promising heat transfer agents in new-generation nuclear power plants, such as fast-neutron reactors and hybrid tokamaks—fusion neutron sources (FNSs). We have been investigating hydrodynamics and heat exchange of liquid metals for many years, trying to reproduce the conditions close to those in fast reactors and fusion neutron sources. In the latter case, the liquid metal flow takes place in a strong magnetic field and strong thermal loads resulting in development of thermogravitational convection in the flow. In this case, quite dangerous regimes of magnetohydrodynamic (MHD) heat exchange not known earlier may occur that, in combination with other long-known regimes, for example, the growth of hydraulic drag in a strong magnetic field, make the possibility of creating a reliable FNS cooling system with a liquid metal heat carrier problematic. There exists a reasonable alternative to liquid metals in FNS, molten salts, namely, the melt of lithium and beryllium fluorides (Flibe) and the melt of fluorides of alkali metals (Flinak). Molten salts, however, are poorly studied media, and their application requires detailed scientific substantiation. We analyze the modern state of the art of studies in this field. Our contribution is to answer the following question: whether above-mentioned extremely dangerous regimes of MHD heat exchange detected in liquid metals can exist in molten salts. Experiments and numerical simulation were performed in order to answer this question. The experimental test facility represents a water circuit, since water (or water with additions for increasing its electrical conduction) is a convenient medium for laboratory simulation of salt heat exchange in FNS conditions. Local heat transfer coefficients along the heated tube, three-dimensional (along the length and in the cross section, including the viscous sublayer) fields of averaged temperature and temperature pulsations are studied. The probe method for measurements in a flow is described in detail. Experimental data are designated for verification of codes simulating heat exchange of molten salts.

Energy Conservation and the Promotion of Legionella pneumophila Growth: The Probable Role of Heat Exchangers in a Nosocomial Outbreak.

PubMed

Bédard, Emilie; Lévesque, Simon; Martin, Philippe; Pinsonneault, Linda; Paranjape, Kiran; Lalancette, Cindy; Dolcé, Charles-Éric; Villion, Manuela; Valiquette, Louis; Faucher, Sébastien P; Prévost, Michèle

2016-12-01

OBJECTIVE To determine the source of a Legionella pneumophila serogroup 5 nosocomial outbreak and the role of the heat exchanger installed on the hot water system within the previous year. SETTING A 400-bed tertiary care university hospital in Sherbrooke, Canada. METHODS Hot water samples were collected and cultured for L. pneumophila from 25 taps (baths and sinks) within wing A and 9 taps in wing B. Biofilm (5) and 2 L water samples (3) were collected within the heat exchangers for L. pneumophila culture and detection of protists. Sequence-based typing was performed on strain DNA extracts and pulsed-field gel electrophoresis patterns were analyzed. RESULTS Following 2 cases of hospital-acquired legionellosis, the hot water system investigation revealed a large proportion of L. pneumophila serogroup 5 positive taps (22/25 in wing A and 5/9 in wing B). High positivity was also detected in the heat exchanger of wing A in water samples (3/3) and swabs from the heat exchanger (4/5). The outbreak genotyping investigation identified the hot water system as the source of infections. Genotyping results revealed that all isolated environmental strains harbored the same related pulsed-field gel electrophoresis pattern and sequence-based type. CONCLUSIONS Two cases of hospital-acquired legionellosis occurred in the year following the installation of a heat exchanger to preheat hospital hot water. No cases were reported previously, although the same L. pneumophila strain was isolated from the hot water system in 1995. The heat exchanger promoted L. pneumophila growth and may have contributed to confirmed clinical cases. Infect. Control Hosp. Epidemiol. 2016;1475-1480.

Patients With Failed Prior Two-Stage Exchange Have Poor Outcomes After Further Surgical Intervention.

PubMed

Kheir, Michael M; Tan, Timothy L; Gomez, Miguel M; Chen, Antonia F; Parvizi, Javad

2017-04-01

Failure of 2-stage exchange arthroplasty for the management of periprosthetic joint infection (PJI) poses a major clinical challenge. There is a paucity of information regarding the outcomes of further surgical intervention in these patients. Thus, we aim to report the clinical outcomes of subsequent surgery for a failed prior 2-stage exchange arthroplasty. Our institutional database was used to identify 60 patients (42 knees and 18 hips), with a failed prior 2-stage exchange, who underwent further surgical intervention between 1998 and 2012, and had a minimum 2-year follow-up. A retrospective review was performed to extract relevant clinical information, including mortality, microbiology, and subsequent surgeries. Musculoskeletal Infection Society criteria were used to define PJI, and treatment success was defined using Delphi criteria. Irrigation and debridement (I&D) was performed after a failed 2-stage exchange in 61.7% of patients; 56.8% subsequently failed. Forty patients underwent an intended second 2-stage exchange; 6 cases required a spacer exchange. Reimplantation occurred only in 65% of cases, and 61.6% had infection controlled. The 14 cases that were not reimplanted resulted in 6 retained spacers, 5 amputations, 2 PJI-related mortalities, and 1 arthrodesis. Further surgical intervention after a failed prior 2-stage exchange arthroplasty has poor outcomes. Although I&D has a high failure rate, many patients who are deemed candidates for a second 2-stage exchange either do not undergo reimplantation or fail after reimplantation. The management of PJI clearly remains imperfect, and there is a dire need for further innovations that may improve the care of these patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Toward a Multiple Perspective in Family Theory and Practice: The Case of Social Exchange Theory, Symbolic Interactionism, and Conflict Theory.

ERIC Educational Resources Information Center

Rank, Mark R.; LeCroy, Craig W.

1983-01-01

Examines the complementarity of three often-used theories in family research: social exchange theory, symbolic interactionism, and conflict theory. Provides a case example in which a multiple perspective is applied to a problem of marital discord. Discusses implications for the clinician. (Author/WAS)

Experiences from Cross-Institutional Exchanges of Undergraduate Business Student Written Cases

ERIC Educational Resources Information Center

Ross, Douglas N.; Zufan, Pavel; Rosenbloom, Al

2008-01-01

This article describes an undergraduate course assignment that required 134 students in 52 student teams from three universities, two in the United States and one in the Czech Republic, to write, exchange, and give constructive feedback on a student-written strategic management or international business case and its accompanying teaching note. The…

Albuminuria is associated with greater copeptin concentrations in men with type 1 diabetes: A brief report from the T1D exchange Biobank.

PubMed

Bjornstad, Petter; Johnson, Richard J; Snell-Bergeon, Janet K; Pyle, Laura; Davis, Asa; Foster, Nicole; Cherney, David Z; Maahs, David M

2017-02-01

Vasopressin exerts important cardio-renal effects, but remains problematic to measure. Copeptin is a more stable peptide derived from the same precursor molecule. In this case-control study from the Type 1 Diabetes Exchange (T1DX) Biobank registry, men with T1D and albuminuria had greater copeptin concentrations than men with normoalbuminuria. Copyright © 2017 Elsevier Inc. All rights reserved.

Treatment by plasma exchange of a patient with hyperlipidemia and diabetic ketoacidosis with lesional pulmonary edema and acute pancreatitis.

PubMed

Gérard, A; Schooneman, F; Guine, J M; Roche, G; Canton, P; Dureux, J B; Janot, C; Streiff, F

1982-01-01

The authors report a case of severe hypertriglyceridemia (148.5 mmol/l) in a 27-year-old woman admitted for coma of unknown origin. Initial investigations revealed ketoacidosis, pancreatitis and noncardiogenic pulmonary edema. The diabetes was unknown. Ketoacidosis was rapidly controlled. The hypertriglyceridemia was corrected by one course of plasma exchange (4,400 ml) during which the patient returned to consciousness. The patient recovered without any sequelae. Only 2 similar cases, treated by plasma exchange, have been reported in the literature until now.

How can knowledge exchange portals assist in knowledge management for evidence-informed decision making in public health?

PubMed Central

2014-01-01

Background Knowledge exchange portals are emerging as web tools that can help facilitate knowledge management in public health. We conducted a review to better understand the nature of these portals and their contribution to knowledge management in public health, with the aim of informing future development of portals in this field. Methods A systematic literature search was conducted of the peer-reviewed and grey literature to identify articles that described the design, development or evaluation of Knowledge Exchange Portals KEPs in the public health field. The content of the articles was analysed, interpreted and synthesised in light of the objectives of the review. Results The systematic search yielded 2223 articles, of which fifteen were deemed eligible for review, including eight case studies, six evaluation studies and one commentary article. Knowledge exchange portals mainly included design features to support knowledge access and creation, but formative evaluation studies examining user needs suggested collaborative features supporting knowledge exchange would also be useful. Overall web usage statistics revealed increasing use of some of these portals over time; however difficulties remain in retaining users. There is some evidence to suggest that the use of a knowledge exchange portal in combination with tailored and targeted messaging can increase the use of evidence in policy and program decision making at the organisational level. Conclusions Knowledge exchange portals can be a platform for providing integrated access to relevant content and resources in one location, for sharing and distributing information and for bringing people together for knowledge exchange. However more performance evaluation studies are needed to determine how they can best support evidence-informed decision making in public health. PMID:24884530

How can knowledge exchange portals assist in knowledge management for evidence-informed decision making in public health?

PubMed

Quinn, Emma; Huckel-Schneider, Carmen; Campbell, Danielle; Seale, Holly; Milat, Andrew J

2014-05-12

Knowledge exchange portals are emerging as web tools that can help facilitate knowledge management in public health. We conducted a review to better understand the nature of these portals and their contribution to knowledge management in public health, with the aim of informing future development of portals in this field. A systematic literature search was conducted of the peer-reviewed and grey literature to identify articles that described the design, development or evaluation of Knowledge Exchange Portals KEPs in the public health field. The content of the articles was analysed, interpreted and synthesised in light of the objectives of the review. The systematic search yielded 2223 articles, of which fifteen were deemed eligible for review, including eight case studies, six evaluation studies and one commentary article. Knowledge exchange portals mainly included design features to support knowledge access and creation, but formative evaluation studies examining user needs suggested collaborative features supporting knowledge exchange would also be useful. Overall web usage statistics revealed increasing use of some of these portals over time; however difficulties remain in retaining users. There is some evidence to suggest that the use of a knowledge exchange portal in combination with tailored and targeted messaging can increase the use of evidence in policy and program decision making at the organisational level. Knowledge exchange portals can be a platform for providing integrated access to relevant content and resources in one location, for sharing and distributing information and for bringing people together for knowledge exchange. However more performance evaluation studies are needed to determine how they can best support evidence-informed decision making in public health.

75 FR 77636 - Public Information Exchange on EPA Nanomaterial Case Studies

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-13

... state of nanotechnology, much remains to be learned about the characteristics and effects of nanomaterials before such assessments can be accomplished. In its 2007 Nanotechnology White Paper (2007, p. 89...

Travelling "the Caledonian Way": Education Policy Learning and the Making of Europe

ERIC Educational Resources Information Center

Grek, Sotiria

2015-01-01

The paper examines the case of education policy learning in Europe and argues that, contrary to dominant assumptions, education is a fruitful area for the analysis of Europeanising processes. More specifically, an examination of the case of the Scottish school inspectorate's European exchanges is useful in relation to the study of international…

Managing Resource Dependence Difficulties in African Higher Education: The Case of Multiple Exchange Relationships

ERIC Educational Resources Information Center

Wangenge-Ouma, Gerald

2011-01-01

The paper has a twofold structure and focus. The first part is an examination of the funding challenges facing African universities resulting mainly from public finance difficulties, and the second part is a case study of how some Kenyan and South African public universities have attempted to mitigate resource dependence difficulties through…

Dissociation of diatomic molecules and the exact-exchange Kohn-Sham potential: the case of LiF

NASA Astrophysics Data System (ADS)

Makmal, Adi; Kuemmel, Stephan; Kronik, Leeor

2011-03-01

The incorrect fractional-charge dissociation of stretched diatomic molecules, predicted by semi-local exchange-correlation functionals, is revisited. This difficulty can be overcome with asymptotically correct non-local potential operators, but should also be absent in exact Kohn-Sham theory, where the potential is local. Here, we show, for the illustrative case of the LiF dimer, that the exact-exchange local Kohn-Sham potential, constructed within the Krieger, Li, and Iafrate (KLI) approximation, can lead to binding energy and charge dissociation curves that are qualitatively correct. This correct behavior is traced back to a characteristic ``step'' structure in the local exchange potential and its relation to the Kohn-Sham eigenvalues is analyzed.

Evidence of MRSE on a gentamicin and vancomycin impregnated polymethyl-methacrylate (PMMA) bone cement spacer after two-stage exchange arthroplasty due to periprosthetic joint infection of the knee

PubMed Central

2014-01-01

Background Periprosthetic joint infections (PJI) are often treated by two stage exchange with the use of an antibiotic impregnated spacer. Most of the two-stage exchange algorithms recommend the implantation of an antibiotic-impregnated spacer during the first stage for a period of 2–24 weeks before reimplantation of the new prosthesis. For the spacer to have a therapeutic effect, the local antibiotic concentration must be greater than the minimal inhibition concentration (MIC) against the pathogens causing the PJI. It must remain so for the entire spacer period, otherwise recurrence of infection or resistances might occur. The question as to whether a sufficient concentration of antibiotics in vivo is reached for the entire spacer period has not been answered satisfactorily. Case presentation We here present a case of a histologically confirmed chronic PJI 20 month after primary arthroplasty. The primary knee arthroplasty was performed due to osteoarthritis of the joint. Initial assessment did not detect a causative pathogen, and two stage exchange with a vancomycin-gentamycin impregnated spacer was performed. At the time of reimplantation, sonication of the explanted spacer revealed a multi-resistant strain of staphylococcus epidermidis on the device and in the joint. Adaption of the therapy and prolonged treatment successfully eradicated the infection. Conclusion According to the authors’ knowledge, the case presented here confirms for the first time the surface contamination (proven through sonication) of a vancomycin-/gentamicin- impregnated Vancogenx®-spacer with a MRSE after ten weeks of implantation. This case study demonstrates the difficulties still associated with the diagnostics of PJI and the published different two stage treatment regimes with the use of antibiotic impregnated spacers. PMID:24641471

Thermal-hydraulic posttest analysis for the ANL/MCTF 360/sup 0/ model heat-exchanger water test under mixed convection. [LMFBR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, C.I.; Sha, W.T.; Kasza, K.E.

As a result of the uncertainties in the understanding of the influence of thermal-buoyancy effects on the flow and heat transfer in Liquid Metal Fast Breeder Reactor heat exchangers and steam generators under off-normal operating conditions, an extensive experimental program is being conducted at Argonne National Laboratory to eliminate these uncertainties. Concurrently, a parallel analytical effort is also being pursued to develop a three-dimensional transient computer code (COMMIX-IHX) to study and predict heat exchanger performance under mixed, forced, and free convection conditions. This paper presents computational results from a heat exchanger simulation and compares them with the results from amore » test case exhibiting strong thermal buoyancy effects. Favorable agreement between experiment and code prediction is obtained.« less

Ontology-Based Exchange and Immediate Application of Business Calculation Definitions for Online Analytical Processing

NASA Astrophysics Data System (ADS)

Kehlenbeck, Matthias; Breitner, Michael H.

Business users define calculated facts based on the dimensions and facts contained in a data warehouse. These business calculation definitions contain necessary knowledge regarding quantitative relations for deep analyses and for the production of meaningful reports. The business calculation definitions are implementation and widely organization independent. But no automated procedures facilitating their exchange across organization and implementation boundaries exist. Separately each organization currently has to map its own business calculations to analysis and reporting tools. This paper presents an innovative approach based on standard Semantic Web technologies. This approach facilitates the exchange of business calculation definitions and allows for their automatic linking to specific data warehouses through semantic reasoning. A novel standard proxy server which enables the immediate application of exchanged definitions is introduced. Benefits of the approach are shown in a comprehensive case study.

Percutaneous cardiopulmonary support to treat suspected venous air embolism with cardiac arrest during open eye surgery: a case report.

PubMed

Shin, Seokyung; Nam, Bokyung; Soh, Sarah; Koo, Bon-Nyeo

2014-11-01

We report a case of possible venous air embolism (VAE) during trans pars plana vitrectomy with air-fluid exchange of the vitreous cavity. Shortly after initiation of air-fluid exchange, decreases in end-tidal CO2, oxygen saturation, and blood pressure were observed. The patient rapidly progressed to cardiac arrest unresponsive to cardiopulmonary resuscitation, and recovered after the application of percutaneous cardiopulmonary support. Prompt termination of air infusion is needed when VAE is suspected during air-fluid exchange, and extracorporeal life support should be considered in fatal cases. Although the incidence is rare the possibility of VAE during ophthalmic surgery clearly exists, and therefore awareness and vigilant monitoring seem critical.

Online hydrogen/deuterium exchange performed in the ion mobility cell of a hybrid mass spectrometer.

PubMed

Nagy, Kornél; Redeuil, Karine; Rezzi, Serge

2009-11-15

The present paper describes the performance of online, gas-phase hydrogen/deuterium exchange implemented in the ion mobility cell of a quadrupole time-of-flight mass spectrometer. Deuterium oxide and deuterated methanol were utilized to create deuterated vapor that is introduced into the ion mobility region of the mass spectrometer. Hydrogen/deuterium exchange occurs spontaneously in the milliseconds time frame without the need of switching the instrument into ion mobility mode. The exchange was studied in case of low molecular weight molecules and proteins. The observed number of exchanged hydrogens was equal to the number of theoretically exchangeable hydrogens for all low molecular weight compounds. This method needs only minimal instrumental modifications, is simple, cheap, environment friendly, compatible with ultraperformance liquid chromatography, and can be implemented on commercially available instruments. It does not compromise choice of liquid chromatographic solvents and accurate mass or parallel-fragmentation (MS(E)) methods. The performance of this method was compared to that of conventional alternatives where the deuterated solvent is introduced into the cone gas of the instrument. Although the degree of exchange was similar between the two methods, the "cone gas method" requires 10 times higher deuterated solvent volumes (50 muL/min) and offers reduced sensitivity in the tandem mass spectrometry (MS/MS) mode. The presented method is suggested as a standard future element of mass spectrometers to aid online structural characterization of unknowns and to study conformational changes of proteins with hydrogen/deuterium exchange.

Bimetallic nanoparticles synthesized in microemulsions: A computer simulation study on relationship between kinetics and metal segregation.

PubMed

Tojo, Concha; Buceta, David; López-Quintela, M Arturo

2018-01-15

Computer simulations were carried out to study the origin of the different metal segregation showed by bimetallic nanoparticles synthesized in microemulsions. Our hypothesis is that the kinetics of nanoparticle formation in microemulsions has to be considered on terms of two potentially limiting factors, chemical reaction itself and the rate of reactants exchange between micelles. From the kinetic study it is deduced that chemical reduction in microemulsions is a pseudo first-order process, but not from the beginning. At the initial stage of the synthesis, redistribution of reactants between micelles is controlled by the intermicellar exchange rate, meanwhile the core and middle layers are being built. This exchange control has a different impact depending on the reduction rate of the particular metal in relation to the intermicellar exchange rate. For the case of Au/Pt nanoparticles, the kinetic constant of Au (fast reduction) is strongly dependent on intermicellar exchange rate and reactant concentration. On the contrary, the kinetic constant of Pt (slower reduction) remains constant. Therefore, the fact that the reaction takes place in a microemulsion affects more or less depending on the reduction rate of the metals. As a consequence, the final nanostructure not only depends on difference between the reduction rates of both metals, but also on the reduction rate of each metal in relation to the intermicellar exchange rate. Copyright © 2017 Elsevier Inc. All rights reserved.

Long-Term Percutaneous Nephrostomy Management of Malignant Urinary Obstruction: Estimation of Optimal Exchange Frequency and Estimation of the Financial Impact of Patient Compliance.

PubMed

McDevitt, Joseph L; Acosta-Torres, Stefany; Zhang, Ning; Hu, Tianshen; Odu, Ayobami; Wang, Jijia; Xi, Yin; Lamus, Daniel; Miller, David S; Pillai, Anil K

2017-07-01

To estimate the least costly routine exchange frequency for percutaneous nephrostomies (PCNs) placed for malignant urinary obstruction, as measured by annual hospital charges, and to estimate the financial impact of patient compliance. Patients with PCNs placed for malignant urinary obstruction were studied from 2011 to 2013. Exchanges were classified as routine or due to 1 of 3 complication types: mechanical (tube dislodgment), obstruction, or infection. Representative cases were identified, and median representative charges were used as inputs for the model. Accelerated failure time and Markov chain Monte Carlo models were used to estimate distribution of exchange types and annual hospital charges under different routine exchange frequency and compliance scenarios. Long-term PCN management was required in 57 patients, with 87 total exchange encounters. Median representative hospital charges for pyelonephritis and obstruction were 11.8 and 9.3 times greater, respectively, than a routine exchange. The projected proportion of routine exchanges increased and the projected proportion of infection-related exchanges decreased when moving from a 90-day exchange with 50% compliance to a 60-day exchange with 75% compliance, and this was associated with a projected reduction in annual charges. Projected cost reductions resulting from increased compliance were generally greater than reductions resulting from changes in exchange frequency. This simulation model suggests that the optimal routine exchange interval for PCN exchange in patients with malignant urinary obstruction is approximately 60 days and that the degree of reduction in charges likely depends more on patient compliance than exact exchange interval. Copyright © 2017 SIR. Published by Elsevier Inc. All rights reserved.

17 CFR 201.222 - Prehearing submissions.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Prehearing submissions. 201.222 Section 201.222 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION RULES OF... of its case or defense; (2) The legal theories upon which it will rely; (3) Copies and a list of...

17 CFR 201.222 - Prehearing submissions.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 17 Commodity and Securities Exchanges 2 2011-04-01 2011-04-01 false Prehearing submissions. 201.222 Section 201.222 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION RULES OF... of its case or defense; (2) The legal theories upon which it will rely; (3) Copies and a list of...

17 CFR 201.222 - Prehearing submissions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 17 Commodity and Securities Exchanges 3 2014-04-01 2014-04-01 false Prehearing submissions. 201.222 Section 201.222 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION RULES OF... of its case or defense; (2) The legal theories upon which it will rely; (3) Copies and a list of...

17 CFR 201.222 - Prehearing submissions.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 17 Commodity and Securities Exchanges 2 2013-04-01 2013-04-01 false Prehearing submissions. 201.222 Section 201.222 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION RULES OF... of its case or defense; (2) The legal theories upon which it will rely; (3) Copies and a list of...

17 CFR 201.222 - Prehearing submissions.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 17 Commodity and Securities Exchanges 2 2012-04-01 2012-04-01 false Prehearing submissions. 201.222 Section 201.222 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION RULES OF... of its case or defense; (2) The legal theories upon which it will rely; (3) Copies and a list of...

Shuttle APS propellant thermal conditioner study

NASA Technical Reports Server (NTRS)

Fulton, D. L.

1971-01-01

The conditioner design concept selected for evaluation consists of an integral reactor and baffle-type heat exchanger. Heat exchange is accomplished by flowing reactor hot gases past a series of slotted and formed plates, through which the conditioned propellant flows. Heat transfer analysis has resulted in the selection of a reactor hot gas nominal mixture ratio of 1.0, giving a combustion temperature of 1560 F with a hydrogen inlet temperature of 275 R. Worst case conditions result in a combustion gas temperature of 2060 F, satisfying the condition of no damage to the conditioner in case of failure to flow cold fluid. In addition, evaluation of hot gas flow requirements and conditioner weight has resulted in the selection of a reactor hot gas exhaust temperature of 750 R.

Advancing the hydrogen safety knowledge base

DOE PAGES

Weiner, S. C.

2014-08-29

The International Energy Agency's Hydrogen Implementing Agreement (IEA HIA) was established in 1977 to pursue collaborative hydrogen research and development and information exchange among its member countries. Information and knowledge dissemination is a key aspect of the work within IEA HIA tasks, and case studies, technical reports and presentations/publications often result from the collaborative efforts. The work conducted in hydrogen safety under Task 31 and its predecessor, Task 19, can positively impact the objectives of national programs even in cases for which a specific task report is not published. As a result, the interactions within Task 31 illustrate how technologymore » information and knowledge exchange among participating hydrogen safety experts serve the objectives intended by the IEA HIA.« less

Revised Standard Rules Tender Governing Motor Carrier Transportation

DOT National Transportation Integrated Search

2002-05-10

The following case study provides an in-depth view of the deployment of the safety information exchange components of the Commercial Vehicle Information Systems and Networks (CVISN) technology program in Connecticut. It describes successful practices...

A multi-species exchange model for fully fluctuating polymer field theory simulations.

PubMed

Düchs, Dominik; Delaney, Kris T; Fredrickson, Glenn H

2014-11-07

Field-theoretic models have been used extensively to study the phase behavior of inhomogeneous polymer melts and solutions, both in self-consistent mean-field calculations and in numerical simulations of the full theory capturing composition fluctuations. The models commonly used can be grouped into two categories, namely, species models and exchange models. Species models involve integrations of functionals that explicitly depend on fields originating both from species density operators and their conjugate chemical potential fields. In contrast, exchange models retain only linear combinations of the chemical potential fields. In the two-component case, development of exchange models has been instrumental in enabling stable complex Langevin (CL) simulations of the full complex-valued theory. No comparable stable CL approach has yet been established for field theories of the species type. Here, we introduce an extension of the exchange model to an arbitrary number of components, namely, the multi-species exchange (MSE) model, which greatly expands the classes of soft material systems that can be accessed by the complex Langevin simulation technique. We demonstrate the stability and accuracy of the MSE-CL sampling approach using numerical simulations of triblock and tetrablock terpolymer melts, and tetrablock quaterpolymer melts. This method should enable studies of a wide range of fluctuation phenomena in multiblock/multi-species polymer blends and composites.

The rise of injecting drug use in east Africa: a case study from Kenya

PubMed Central

Beckerleg, Susan; Telfer, Maggie; Hundt, Gillian Lewando

2005-01-01

Studies on injecting drug use in East Africa are reviewed. The existingstudies document the spread of heroin injection in Kenya and Tanzania, both countries where HIV rates are high. No data from Uganda on injecting drug use was found by the authors. A case study of the growth of heroin injection in a Kenyan coastal town is presented. The need for needle-exchange programmes and other prevention services is discussed. PMID:16122382

The phase diagrams of the ± K model on the Bethe lattice

NASA Astrophysics Data System (ADS)

Albayrak, Erhan

2015-07-01

The biquadratic exchange interaction is randomized in a bimodal form with probabilities (p) and (1 - p) for the cases with K > 0 (attractive case) and K < 0 (repulsive case), respectively, and its effects on the phase diagrams of the spin-1 Blume-Emery-Griffiths model are studied on the Bethe lattice by using the recursion relations. It was found that the critical behaviors of the model change drastically.

Science in the Public Sphere: Greater Sage-grouse Conservation Planning from a Transdisciplinary Perspective

USGS Publications Warehouse

Torregrosa, Alicia; Casazza, Michael L.; Caldwell, Margaret R.; Mathiasmeier, Teresa A.; Morgan, Peter M.; Overton, Cory T.

2010-01-01

Integration of scientific data and adaptive management techniques is critical to the success of species conservation, however, there are uncertainties about effective methods of knowledge exchange between scientists and decisionmakers. The conservation planning and implementation process for Greater Sage-grouse (Centrocercus urophasianus; ) in the Mono Basin, Calif. region, was used as a case study to observe the exchange of scientific information among stakeholders with differing perspectives; resource manager, scientist, public official, rancher, and others. The collaborative development of a risk-simulation model was explored as a tool to transfer knowledge between stakeholders and inform conservation planning and management decisions. Observations compiled using a transdisciplinary approach were used to compare the exchange of information during the collaborative model development and more traditional interactions such as scientist-led presentations at stakeholder meetings. Lack of congruence around knowledge needs and prioritization led to insufficient commitment to completely implement the risk-simulation model. Ethnographic analysis of the case study suggests that further application of epistemic community theory, which posits a strong boundary condition on knowledge transfer, could help support application of risk simulation models in conservation-planning efforts within similarly complex social and bureaucratic landscapes.

Statistical approach to partial equilibrium analysis

NASA Astrophysics Data System (ADS)

Wang, Yougui; Stanley, H. E.

2009-04-01

A statistical approach to market equilibrium and efficiency analysis is proposed in this paper. One factor that governs the exchange decisions of traders in a market, named willingness price, is highlighted and constitutes the whole theory. The supply and demand functions are formulated as the distributions of corresponding willing exchange over the willingness price. The laws of supply and demand can be derived directly from these distributions. The characteristics of excess demand function are analyzed and the necessary conditions for the existence and uniqueness of equilibrium point of the market are specified. The rationing rates of buyers and sellers are introduced to describe the ratio of realized exchange to willing exchange, and their dependence on the market price is studied in the cases of shortage and surplus. The realized market surplus, which is the criterion of market efficiency, can be written as a function of the distributions of willing exchange and the rationing rates. With this approach we can strictly prove that a market is efficient in the state of equilibrium.

Marine Language Exchange Program: A 21st Century International and Interdisciplinary Partnership

NASA Astrophysics Data System (ADS)

Robigou, V.; Nichols-Pecceu, M.

2001-12-01

The ability of scientists to communicate across cultural and linguistic barriers is crucial for the global economic sustainability and protection of the world\\'{}s oceans. Yet students with majors in the sciences and engineering constitute less than 2% of those who study abroad each year. And even rarer are students who study in countries where English is not the first language. The Marine Language Exchange program is a case study of an international and interdisciplinary collaboration between faculties in the languages and the sciences who address this gap. A consortium of U.S. and European institutions including Eckerd College (Florida), University of Washington (Washington), University of Hilo (Hawaii), Université de la Rochelle (France), Université de Liège (Belgium), and Universidad de Las Palmas (Spain) is developing a multilingual, marine sciences exchange program in an effort to internationalize their Marine Sciences departments. The program includes a three-week, intensive "bridge" course designed to reinforce second language skills in the context of marine sciences, and prepare undergraduate students for the cultural and educational differences of their host country. Following this immersion experience students from each institution enroll in courses abroad including marine sciences specialization for full academic credit. This session will review the Marine Language Exchange program activities since 2000 and will discuss the ideological and practical aspects of the program. The program successes, difficulties and future directions will also be presented. Different disciplinary approaches -Second Language Acquisition, English as a Second Language and Marine Science- prepare science students to contribute to the study and the management of the world\\'{}s oceans with an awareness of the cultural issues reflected by national marine policies. Based on this case study, other universities could initiate their own international and interdisciplinary collaboration to facilitate a better understanding of other planetary issues.

The role of the (111) texture on the exchange bias and interlayer coupling effects observed in sputtered NiFe/IrMn/Co trilayers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Castro, I. L.; Nascimento, V. P.; Passamani, E. C.

2013-05-28

Magnetic properties of sputtered NiFe/IrMn/Co trilayers grown on different seed layers (Cu or Ta) deposited on Si (100) substrates were investigated by magnetometry and ferromagnetic resonance measurements. Exchange bias effect and magnetic spring behavior have been studied by changing the IrMn thickness. As shown by X-ray diffraction, Ta and Cu seed layers provoke different degrees of (111) fcc-texture that directly affect the exchange bias and indirectly modify the exchange spring coupling behavior. Increasing the IrMn thickness, it was observed that the coupling angle between the Co and NiFe ferromagnetic layers increases for the Cu seed system, but it reduces formore » the Ta case. The results were explained considering (i) different anisotropies of the Co and IrMn layers induced by the different degree of the (111) texture and (ii) the distinct exchange bias set at the NiFe/IrMn and IrMn/Co interfaces in both systems. The NiFe and Co interlayer coupling angle is strongly correlated with both exchange bias and exchange magnetic spring phenomena. It was also shown that the highest exchange bias field occurs when an unstressed L1{sub 2} IrMn structure is stabilized.« less

Negotiating multisectoral evidence: a qualitative study of knowledge exchange at the intersection of transport and public health.

PubMed

Guell, Cornelia; Mackett, Roger; Ogilvie, David

2017-01-05

For the prevention and control of chronic diseases, two strategies are frequently highlighted: that public health should be evidence based, and that it should develop a multisectoral approach. At the end of a natural experimental study of the health impacts of new transport infrastructure, we took the opportunity of a knowledge exchange forum to explore how stakeholders assessed, negotiated and intended to apply multisectoral evidence in policy and practice at the intersection of transport and health. We aimed to better understand the challenges they faced in knowledge exchange, as well as their everyday experiences with working in multisectoral remits. In 2015, we conducted participant observation during an interactive event with 41 stakeholders from national and local government, the third sector and academia in Cambridge, UK. Formal and informal interactions between stakeholders were recorded in observational field notes. We also conducted 18 semistructured interviews reflecting on the event and on knowledge exchange in general. We found that stakeholders negotiated a variety of challenges. First, stakeholders had to negotiate relatively new formal and informal multisectoral remits; and how to reconcile the differing expectations of transport specialists, who tended to emphasise the importance of precedence in guiding action, and health specialists' concern for the rigour and synthesis of research evidence. Second, research in this field involved complex study designs, and often produced evidence with uncertain transferability to other settings. Third, health outcomes of transport schemes had political traction and were used strategically but not easily translated into cost-benefit ratios. Finally, knowledge exchange meant multiple directions of influence. Stakeholders were concerned that researchers did not always have skills to translate their findings into understandable evidence, and some stakeholders would welcome opportunities to influence research agendas. This case study of stakeholders' experiences indicates that multisectoral research, practice and policymaking requires the ability and capacity to locate, understand and communicate complex evidence from a variety of disciplines, and integrate different types of evidence into clear business cases beyond sectoral boundaries.

An Investigation of Factors Associated with Student Participation in Study Abroad

ERIC Educational Resources Information Center

Doyle, Stephanie; Gendall, Philip; Meyer, Luanna H.; Hoek, Janet; Tait, Carolyn; McKenzie, Lynanne; Loorparg, Avatar

2010-01-01

International student exchange programs are widely promoted in higher education as a means of developing desirable intercultural skills and understanding among students. This multimethod study employed data from student surveys, tertiary institution case studies, and interviews with key stakeholders to identify factors that inhibited or promoted…

Stabilization of magnetic skyrmions by RKKY interactions

NASA Astrophysics Data System (ADS)

Bezvershenko, Alla V.; Kolezhuk, Alexei K.; Ivanov, Boris A.

2018-02-01

We study the stabilization of an isolated magnetic skyrmion in a magnetic monolayer on a nonmagnetic conducting substrate via the Ruderman-Kittel-Kasuya-Yosida (RKKY) exchange interaction. Two different types of the substrate are considered, usual normal metal and single-layer graphene. While the full stability analysis for skyrmions in the presence of the RKKY coupling requires a separate effort that is outside the scope of this work, we are able to study the radial stability (stability of a skyrmion against collapse) using variational energy estimates obtained within first-order perturbation theory, with the unperturbed Hamiltonian describing the isotropic Heisenberg magnet, and the two perturbations being the RKKY exchange and the easy-axis anisotropy. We show that a proper treatment of the long-range nature of the RKKY interaction leads to a qualitatively different stabilization scenario compared to previous studies, where solitons were stabilized by the frustrated exchange coupling (leading to terms with the fourth power of the magnetization gradients) or by the Dzyaloshinskii-Moriya interaction (described by terms linear in the magnetization gradients). In the case of a metallic substrate, the skyrmion stabilization is possible under restrictive conditions on the Fermi surface parameters, while in the case of a graphene substrate the stabilization is naturally achieved in several geometries with a lattice-matching of graphene and magnetic layer.

Severe leptospirosis with multiple organ failure successfully treated by plasma exchange and high-volume hemofiltration.

PubMed

Bourquin, Vincent; Ponte, Belén; Hirschel, Bernard; Pugin, Jérôme; Martin, Pierre-Yves; Saudan, Patrick

2011-01-01

Background. Leptospirosis is a spirochetal zoonosis with complex clinical features including renal and liver failure. Case report. We report the case of a Swiss fisherman presenting with leptospirosis. After initial improvement, refractory septic shock and severe liver and kidney failure developed. The expected mortality was estimated at 90% with clinical scores. The patient underwent plasma exchanges and high-volume hemofiltration (HVHF) with complete recovery of hepatic and kidney functions. Discussion. Plasma exchanges and HVHF may confer survival benefit on patients with severe leptospirosis, refractory septic shock, and multiple-organ failure.

How to govern physician-hospital exchanges: contractual and relational issues in Belgian hospitals.

PubMed

Trybou, Jeroen; Gemmel, Paul; Annemans, Lieven

2014-07-01

Our aim was to investigate contractual mechanisms in physician-hospital exchanges. The concepts of risk-sharing and the nature of physician-hospital exchanges - transactional versus relational - were studied. Two qualitative case studies were performed in Belgium. Hospital executives and physicians were interviewed to develop an in-depth understanding of contractual and relational issues that shape physician-hospital contracting in acute care hospitals. The underlying theoretical concepts of agency theory and social exchange theory were used to analyse the data. Our study found that physician-hospital contracting is highly complex. The contract is far more than an economic instrument governing financial aspects. The effect of the contract on the nature of exchange - whether transactional or relational - also needs to be considered. While it can be argued that contractual governance methods are increasingly necessary to overcome the difficulties that arise from the fragmented payment framework by aligning incentives and sharing financial risk, they undermine the necessary relational governance. Relational qualities such as mutual trust and an integrative view on physician-hospital exchanges are threatened, and may be difficult to sustain, given the current fragmentary payment framework. Since health care policy makers are increasing the financial risk borne by health care providers, it can be argued that this also increases the need to share financial risk and to align incentives between physician and hospital. However, our study demonstrates that while economic alignment is important in determining physician-hospital contracts, the corresponding impact on working relationships should also be considered. Moreover, it is important to avoid a relationship between hospital and physician predominantly characterized by transactional exchanges thereby fostering an unhealthy us-and-them divide and mentality. Relational exchange is a valuable alternative to contractual exchange, stimulating an integrated hospital-physician relationship. Unfortunately, the fragmented payment framework characterized by unaligned incentives is perceived as an obstacle to realize effective collaboration. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Standards for Data Exchange and Case Management Information Systems in Support of Comprehensive Integrated School-Linked Services. Version 2.0.

ERIC Educational Resources Information Center

Far West Lab. for Educational Research and Development, San Francisco, CA.

This report is intended as a guide for local comprehensive integrated school-linked services sites and software vendors in developing and implementing case management information systems for the exchange and management of client data. The report is also intended to influence new development and future revisions of data systems, databases, and…

Retinal damage caused by air-fluid exchange during pars plana vitrectomy.

PubMed

Yang, Sam S; McDonald, H Richard; Everett, A I; Johnson, Robert N; Jumper, J Michael; Fu, Arthur D

2006-03-01

To report two cases of retinal damage associated with air infusion during pars plana vitrectomy. Observational case report. The authors reviewed the course of two patients who had retinal damage during par plana vitrectomy and air-fluid exchange for the treatment of macular hole and optic pit-related macular detachment, respectively. The intraoperative observations, postoperative course, and outcomes were reported. As a result of high air infusion flow during air-fluid exchange, retinal damage was created in the area contralateral to the infusion port. In Case 1, an oval area of whitening was noted on the first postoperative day. This area subsequently developed into a large retinal break associated with retinal detachment. In the second case, retinal whitening was noted intraoperatively. This region of pallor resolved quickly during the early postoperative period but resulted in a corresponding inferotemporal visual field defect. High infusion flow during air-fluid exchange in eyes undergoing vitrectomy surgery may result in significant retinal damage. This pressure-induced trauma initially causes retinal whitening that may be seen intraoperatively or during the early postoperative period. The region of damaged retina may develop a retinal break and detachment or a corresponding visual field defect.

A follow-up ¹⁸F-FDG brain PET study in a case of Hashimoto's encephalopathy causing drug-resistant status epilepticus treated with plasmapheresis.

PubMed

Pari, Elisa; Rinaldi, Fabrizio; Premi, Enrico; Codella, Maria; Rao, Renata; Paghera, Barbara; Panarotto, Maria Beatrice; De Maria, Giovanni; Padovani, Alessandro

2014-04-01

Hashimoto's encephalopathy (HE) is a rare neuropsychiatric syndrome associated with antithyroid antibodies. It may have an acute onset (episodes of cerebral ischemia, seizure, and psychosis) or it may present as an indolent form (depression, cognitive decline, myoclonus, tremors, and fluctuations in level of consciousness). We here describe a case of encephalopathy presenting as non-convulsive status epilepticus associated with Hashimoto's thyroiditis (HT), unresponsive to corticosteroid therapy, with improvement after plasma exchange treatment. A previously healthy 19-year-old woman, presented generalized tonic-clonic seizures. About a month later, she manifested a speech disorder characterized by difficulties in the production and comprehension of language. Within a few days she also developed confusion and difficulties in recognizing familiar places, with gradual worsening over time. EEG revealed a non-convulsive status epilepticus (NCSE). CSF examination showed slightly elevated cell count and four oligoclonal bands. MRI was unremarkable, and (18)F-FDG brain PET showed widespread hypometabolism, mostly in posterior regions bilaterally. Laboratory and ultrasound findings showed signs of HT. Treatment with steroid was introduced without any improvement. After five sessions of plasma exchange there was a decrease of antithyroid antibodies, as well as EEG and clinical improvement. Three months after discharge (18)F-FDG brain PET showed a complete normalization of the picture, and the patient was asymptomatic. This report emphasizes the successful treatment of HE with plasma exchange in a patient who presented with NCSE. Based on the actual evidence, the term "Encephalopathy associated with Hashimoto's thyroiditis" may be the most proper. Furthermore, to our knowledge, this is the first case of an adult patient studied twice with an (18)F-FDG brain PET: prior to treatment with plasma exchange, and at 3 months follow-up when the patient was clinically completely asymptomatic. Studies in more patients are needed to clarify the relevance of (18)F-FDG brain PET as a possible diagnostic tool for HE.

Effect of pyrazinamide and probenecid on peritoneal urate transport kinetics during continuous ambulatory peritoneal dialysis.

PubMed

Spaia, S; Magoula, I; Tsapas, G; Vayonas, G

2000-01-01

We administered pyrazinamide (PZA) and probenecid (PB) --two well-known modulators of urate transport via the proximal tubules - to evaluate their impact on urate transport through the peritoneal membrane and to clarify mechanisms affecting peritoneal transport. A continuous ambulatory peritoneal dialysis (CAPD) unit in 2nd Hospital of IKA (Social Services Institute), Greece. In 20 stable CAPD patients, on the study day, a 4-hour, 2-L, 1.36% glucose exchange was performed (control exchange). Pyrazinamide 3 g was given orally and another identical exchange was performed (study exchange). The same protocol was repeated with 2 g PB. KtN, peritoneal clearances of urea, creatinine, and urate for each exchange, and mass transfer area coefficients (MTAC) for the three solutes and their dialysate-to-plasma concentration (D/P) ratios were used to estimate peritoneal transport. Administration of PZA resulted in decreased clearances and MTAC values for the three solutes. The D/P ratio decreased significantly only for urate, indicating a more intense influence of PZA on urate. After PB administration, clearances of urea, creatinine, and urate were increased. MTAC and DIP ratio increased significantly only for urate (p < 0.05), demonstrating an action similar to that exerted on renal tubules. These findings provide evidence that unrestricted diffusion is not the only transport mechanism in the case of urate, and demonstrate the existence of an active mechanism in peritoneal urate transport with a reabsorptive and, probably, a secretive component that resembles that of renal tubule urate transport. Attention should be given in the case of CAPD patients undergoing antituberculous (PZA) treatment: it might have a negative impact on urea, creatinine, and urate peritoneal transport rates.

Metabolism and pathophysiology of sodium and chlorine in tissue after neutron irradiation.

PubMed

Koester, L; Knopf, K; Auberger, T

1994-01-01

The photon emission of tissue was measured after radiotherapy with various doses of fission neutrons. Spectral analyses of the decay rates resulted in data for the exchange of sodium and chlorine between the irradiated tissue and the whole body. In 12 cases we found that about three fifths of Na and Cl exchange rapidly between the extravascular and vascular liquids with a turnover half-life of 13 +/- 2 min. Slowly exchangeable or non-exchangeable fractions are deposited in the soft tissue. New defined mass exchange rates for Na and Cl amount to an average of 0.8 mval min-1 kg-1 of soft tissue. The turnover of the electrolytes in tissue with large tumours is about twice that in tissues with small metastasis. Depending on dose, radiotherapy led in all cases to distinct variations of the metabolism. A maximum of the exchange of Cl combined with a minimum of Na occurs at about 85 Gy of conventional or at 10 Gy of lead-filtered fission neutron radiation. These results show directly for the first time the local response of the electrolyte metabolism to therapy.

Analysis and Perspective from the Complex Aerospace Systems Exchange (CASE) 2013

NASA Technical Reports Server (NTRS)

Jones, Kennie H.; Parker, Peter A.; Detweiler, Kurt N.; McGowan, Anna-Maria R.; Dress, David A.; Kimmel, William M.

2014-01-01

NASA Langley Research Center embedded four rapporteurs at the Complex Aerospace Systems Exchange (CASE) held in August 2013 with the objective to capture the essence of the conference presentations and discussions. CASE was established to provide a discussion forum among chief engineers, program managers, and systems engineers on challenges in the engineering of complex aerospace systems. The meeting consists of invited presentations and panels from industry, academia, and government followed by discussions among attendees. This report presents the major and reoccurring themes captured throughout the meeting and provides analysis and insights to further the CASE mission.

Did you have an impact? A theory-based method for planning and evaluating knowledge-transfer and exchange activities in occupational health and safety.

PubMed

Kramer, Desré M; Wells, Richard P; Carlan, Nicolette; Aversa, Theresa; Bigelow, Philip P; Dixon, Shane M; McMillan, Keith

2013-01-01

Few evaluation tools are available to assess knowledge-transfer and exchange interventions. The objective of this paper is to develop and demonstrate a theory-based knowledge-transfer and exchange method of evaluation (KEME) that synthesizes 3 theoretical frameworks: the promoting action on research implementation of health services (PARiHS) model, the transtheoretical model of change, and a model of knowledge use. It proposes a new term, keme, to mean a unit of evidence-based transferable knowledge. The usefulness of the evaluation method is demonstrated with 4 occupational health and safety knowledge transfer and exchange (KTE) implementation case studies that are based upon the analysis of over 50 pre-existing interviews. The usefulness of the evaluation model has enabled us to better understand stakeholder feedback, frame our interpretation, and perform a more comprehensive evaluation of the knowledge use outcomes of our KTE efforts.

Exchange-driven growth.

PubMed

Ben-Naim, E; Krapivsky, P L

2003-09-01

We study a class of growth processes in which clusters evolve via exchange of particles. We show that depending on the rate of exchange there are three possibilities: (I) Growth-clusters grow indefinitely, (II) gelation-all mass is transformed into an infinite gel in a finite time, and (III) instant gelation. In regimes I and II, the cluster size distribution attains a self-similar form. The large size tail of the scaling distribution is Phi(x) approximately exp(-x(2-nu)), where nu is a homogeneity degree of the rate of exchange. At the borderline case nu=2, the distribution exhibits a generic algebraic tail, Phi(x) approximately x(-5). In regime III, the gel nucleates immediately and consumes the entire system. For finite systems, the gelation time vanishes logarithmically, T approximately [lnN](-(nu-2)), in the large system size limit N--> infinity. The theory is applied to coarsening in the infinite range Ising-Kawasaki model and in electrostatically driven granular layers.

Under-humidification and over-humidification during moderate induced hypothermia with usual devices.

PubMed

Lellouche, François; Qader, Siham; Taille, Solenne; Lyazidi, Aissam; Brochard, Laurent

2006-07-01

In mechanically ventilated patients with induced hypothermia, the efficacy of heat and moisture exchangers and heated humidifiers to adequately humidify the airway is poorly known. The aim of the study was to assess the efficacy of different humidification devices during moderate hypothermia. Prospective, cross-over randomized study. Medical Intensive Care Unit in a University Hospital. Nine adult patients hospitalized after cardiac arrest in whom moderate hypothermia was induced (33 degrees C for 24[Symbol: see text]h). Patients were ventilated at admission (period designated "normothermia") with a heat and moisture exchanger, and were randomly ventilated during hypothermia with a heat and moisture exchanger, a heated humidifier, and an active heat and moisture exchanger. Core temperature, inspired and expired gas absolute and relative humidity were measured. Each system demonstrated limitations in its ability to humidify gases in the specific situation of hypothermia. Performances of heat and moisture exchangers were closely correlated to core temperature (r (2)[Symbol: see text]=[Symbol: see text]0.84). During hypothermia, heat and moisture exchangers led to major under-humidification, with absolute humidity below 25[Symbol: see text]mgH(2)O/l. The active heat and moisture exchanger slightly improved humidification. Heated humidifiers were mostly adequate but led to over-humidification in some patients, with inspiratory absolute humidity higher than maximal water content at 33 degrees C with a positive balance between inspiratory and expiratory water content. These results suggest that in the case of moderate hypothermia, heat and moisture exchangers should be used cautiously and that heated humidifiers may lead to over-humidification with the currently recommended settings.

Corrosion of steel drums containing cemented ion-exchange resins as intermediate level nuclear waste

NASA Astrophysics Data System (ADS)

Duffó, G. S.; Farina, S. B.; Schulz, F. M.

2013-07-01

Exhausted ion-exchange resins used in nuclear reactors are immobilized by cementation before being stored. They are contained in steel drums that may undergo internal corrosion depending on the presence of certain contaminants. The objective of this work is to evaluate the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins with different aggressive species. The corrosion potential and the corrosion rate of the steel, and the electrical resistivity of the matrix were monitored for 900 days. Results show that the cementation of ion-exchange resins seems not to pose special risks regarding the corrosion of the steel drums. The corrosion rate of the steel in contact with cemented ion-exchange resins in the absence of contaminants or in the presence of 2.3 wt.% sulphate content remains low (less than 0.1 μm/year) during the whole period of the study (900 days). The presence of chloride ions increases the corrosion rate of the steel at the beginning of the exposure but, after 1 year, the corrosion rate drops abruptly reaching a value close to 0.1 μm/year. This is probably due to the lack of water to sustain the corrosion process. When applying the results obtained in the present work to estimate the corrosion depth of the steel drums containing the cemented radioactive waste after a period of 300 years, it is found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums. Cementation of ion-exchange resins does not seem to pose special risks regarding the corrosion of the steel drums that contained them; even in the case the matrix is highly contaminated with chloride ions.

Improving Information Exchange in the Chicken Processing Sector Using Standardised Data Lists

NASA Astrophysics Data System (ADS)

Donnelly, Kathryn Anne-Marie; van der Roest, Joop; Höskuldsson, Stefán Torfi; Olsen, Petter; Karlsen, Kine Mari

Research has shown that to improve electronic communication between companies, universal standardised data lists are necessary. In food supply chains in particular there is an increased need to exchange data in the wake of food safety incidents. Food supply chain companies already record numerous measurements, properties and parameters. These records are necessary for legal reasons, labelling, traceability, profiling desirable characteristics, showing compliance and for meeting customer requirements. Universal standards for name and content of each of these data elements would improve information exchange between buyers, sellers, authorities, consumers and other interested parties. A case study, carried out for the chicken sector, attempted to identify the most relevant parameters including which of these were already communicated to external bodies.

Positive Culture During Reimplantation Increases the Risk of Subsequent Failure in Two-Stage Exchange Arthroplasty.

PubMed

Tan, Timothy L; Gomez, Miguel M; Manrique, Jorge; Parvizi, Javad; Chen, Antonia F

2016-08-03

It is strongly recommended that tissue and synovial fluid culture samples be obtained during reimplantation performed as part of a 2-stage exchange arthroplasty. The rate of positive cultures during reimplantation and the influence of positive cultures on subsequent outcomes, to our knowledge, are unknown. This study was designed to determine the rate of positive cultures during reimplantation and to investigate the association between positive cultures at reimplantation and subsequent outcomes. We retrospectively reviewed the data of 259 patients who met the Musculoskeletal Infection Society criteria for periprosthetic joint infection (PJI) and who underwent both stages of 2-stage exchange arthroplasty at our institution from 1999 to 2013. Among these patients were 267 PJIs (186 knees and 81 hips); 33 (12.4%) had ≥1 positive culture result at reimplantation. Treatment failure was assessed according to the Delphi-based consensus definition. Logistic regression analysis was performed to assess the predictors of positive culture and risk factors for failure of 2-stage exchange arthroplasty. Of the 33 cases with PJI, 15 (45.5%) had a subsequent failure of the 2-stage exchange arthroplasty compared with 49 (20.9%) of the cases that were culture-negative at reimplantation. When controlling for other variables using multivariate analyses, the risk of treatment failure was higher (odds ratio = 2.53; 95% confidence interval [CI] = 1.13 to 5.64) and reinfection occurred earlier (hazard ratio = 2.00; 95% CI = 1.05 to 3.82) for the cases with a positive culture during reimplantation. The treatment failure rate did not differ (p = 0.73) between cases with ≥2 positive cultures (36.4%) and 1 positive culture (50%). Positive intraoperative culture at the time of reimplantation, regardless of the number of positive samples, was independently associated with >2 times the risk of subsequent treatment failure and earlier reinfection. Surgeons should be aware that a positive culture at the time of reimplantation independently increases the risk of subsequent failure. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2016 by The Journal of Bone and Joint Surgery, Incorporated.

76 FR 6838 - Self-Regulatory Organizations; Chicago Board Options Exchange, Incorporated; Order Approving a...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-08

.... I. Introduction On December 1, 2010, the Chicago Board Options Exchange, Incorporated (``Exchange.... CBOE's proposed rules would require no margin in the case of a spread (i.e., long and short Credit... requires margin of 50% of the margin required on the long or short (credit default swap), whichever is...

78 FR 18403 - Self-Regulatory Organizations; Miami International Securities Exchange LLC; Notice of Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-26

... earlier than 4:00 p.m. ET in the case of an early scheduled close. ``Regulatory Halt'' shall have the... the primary market. Rejection of Incoming Market Orders The Exchange proposes to adopt provisions... that are subject to added risks during such periods. The Exchange believes that the rejection of...

Use of an Airway Exchange Catheter-Assisted Extubation With Continuous End-Tidal Carbon Dioxide Monitoring in a Pediatric Patient With a Known Difficult Airway: A Case Report.

PubMed

Yegian, Courtney C; Volz, Lana M; Galgon, Richard E

2018-05-11

Tracheal extubation in children with known difficult airways is associated with an increased risk of adverse events. Currently, there is no reliable measure to predict the need for emergent reintubation due to airway inadequacy. Airway exchange catheter-assisted extubation has been shown to be a useful adjunct in decreasing the risk of adverse events due to failed extubation. We report a case of using an airway exchange catheter-assisted extubation with continuous end-tidal carbon dioxide monitoring for a pediatric patient with a known difficult airway.

Voices from the Community: A Case for Reciprocity in Service-Learning

ERIC Educational Resources Information Center

d'Arlach, Lucia; Sanchez, Bernadette; Feuer, Rachel

2009-01-01

Few studies have directly examined how recipients of service view the service. This qualitative study presents the results of interviews and observations of nine community members who participated in a service-learning, language exchange program, Intercambio, in which Spanish-speaking Latino immigrants were paired with English-speaking university…

A Case Study: Follow-Up Assessment of Facilitated Communication.

ERIC Educational Resources Information Center

Simon, Elliott W.; And Others

1996-01-01

This study of an adolescent with multiple disabilities, including moderate mental retardation, who was reported to engage in validated facilitated communication (FC) found he did not engage in validated FC; performance was equivalent whether food or nonfood reinforcers were used; and the Picture Exchange Communication System was a valid and…

75 FR 66822 - Study on Extraterritorial Private Rights of Action

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-29

... Extraterritorial Private Rights of Action AGENCY: Securities and Exchange Commission. ACTION: Request for Comments... and thereafter conduct a study to determine the extent to which private rights of action under the... United States to bring actions under Section 10(b) in cases involving transnational securities fraud...

Asperger syndrome related suicidal behavior: two case studies.

PubMed

Kocourkova, Jana; Dudova, Iva; Koutek, Jiri

2013-01-01

Asperger syndrome hinders adaptation to developmental challenges during childhood and adolescence, particularly with regard to interpersonal relationships. Individuals with Asperger syndrome display lack of empathy and limited ability to understand social and emotional exchanges with other people. Individuals with Asperger syndrome are significantly exposed to the risk of suicidal behavior, especially during adolescence. The authors describe cases of suicidal behavior in two adolescent boys with Asperger syndrome.

A Study of the Effectiveness of the Case Method in Teaching Interpersonal Relations to Psychiatric Aides. League Exchange No. 69.

ERIC Educational Resources Information Center

Swatsley, Dolores E.

In a 950-bed state psychiatric hospital, primarily an admission-and-treatment center, the case method was compared with the lecture-discussion method in teaching a unit on interpersonal relations with psychiatric patients to nurse aides. Two groups of 10 aides each were equated for age, sex, formal education, previous inservice training, and…

Trading Up: Chimpanzees (Pan troglodytes) Show Self-Control Through Their Exchange Behavior

PubMed Central

Beran, Michael J.; Rossettie, Mattea S.; Parrish, Audrey E.

2015-01-01

Self-control is defined as the ability or capacity to obtain an objectively more valuable outcome rather than an objectively less valuable outcome though tolerating a longer delay or a greater effort requirement (or both) in obtaining that more valuable outcome. A number of tests have been devised to assess self-control in nonhuman animals, including exchange tasks. In this study, three chimpanzees (Pan troglodytes) participated in a delay of gratification task that required food exchange as the behavioral response that reflected self-control. The chimpanzees were offered opportunities to inhibit eating and instead exchange a currently possessed food item for a different (and sometimes better) item, often needing to exchange several food items before obtaining the highest-valued reward. We manipulated reward type, reward size, reward visibility, delay to exchange, and location of the highest-valued reward in the sequence of exchange events to compare performance within the same individuals. The chimpanzees successfully traded until obtaining the best item in most cases, although there were individual differences among participants in some variations of the test. These results support the idea that self-control is robust in chimpanzees even in contexts in which they perhaps anticipate future rewards and sustain delay of gratification until they can obtain the ultimately most-valuable item. PMID:26325355

Trading up: chimpanzees (Pan troglodytes) show self-control through their exchange behavior.

PubMed

Beran, Michael J; Rossettie, Mattea S; Parrish, Audrey E

2016-01-01

Self-control is defined as the ability or capacity to obtain an objectively more valuable outcome rather than an objectively less valuable outcome though tolerating a longer delay or a greater effort requirement (or both) in obtaining that more valuable outcome. A number of tests have been devised to assess self-control in non-human animals, including exchange tasks. In this study, three chimpanzees (Pan troglodytes) participated in a delay of gratification task that required food exchange as the behavioral response that reflected self-control. The chimpanzees were offered opportunities to inhibit eating and instead exchange a currently possessed food item for a different (and sometimes better) item, often needing to exchange several food items before obtaining the highest valued reward. We manipulated reward type, reward size, reward visibility, delay to exchange, and location of the highest valued reward in the sequence of exchange events to compare performance within the same individuals. The chimpanzees successfully traded until obtaining the best item in most cases, although there were individual differences among participants in some variations of the test. These results support the idea that self-control is robust in chimpanzees even in contexts in which they perhaps anticipate future rewards and sustain delay of gratification until they can obtain the ultimately most valuable item.

May one-stage exchange for Candida albicans peri-prosthetic infection be successful?

PubMed

Jenny, J-Y; Goukodadja, O; Boeri, C; Gaudias, J

2016-02-01

Fungal infection of a total joint arthroplasty has a low incidence but is generally considered as more difficult to cure than bacterial infection. As for bacterial infection, two-stage exchange is considered as the gold standard of treatment. We report two cases of one-stage total joint exchange for fungal peri-prosthetic infection with Candida albicans, where the responsible pathogens was only identified on intraoperative samples. This situation can be considered as a one-stage exchange for fungal peri-prosthetic infection without preoperative identification of the responsible organism, which is considered as having a poor prognosis. Both cases were free of infection after two years. One-stage revision has several potential advantages over two-stage revision, including shorter hospital stay and rehabilitation, no interim period with significant functional impairment, shorter antibiotic treatment, better functional outcome and probably lower costs. We suggest that one-stage revision for C. albicans peri-prosthetic infection may be successful even without preoperative fungal identification. Level IV-Historical cases. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

FOURTH ANNUAL REPORT ON DISTRIBUTION STUDIES BETWEEN MELTS AND SOLID PHASES USING RADIOACTIVE TRACERS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, R.; Orr, W.C.; Katz, L.

Cerium(III) ion in a barium chloride flux does not readily exchangs with any of the ions in solid BaZrO/sub 3/ or BaTiO/sub 3/. It reacts to form new solid phases, which are identified, and does not enter the original crystal lattices at an appreciable rate. The strontium was found to exchange at a measurable rate with barium in BaTiO/sub 3/ and with the corresponding ions in alkaline-earth zirconates. Results of a series of equilibrium and rate measurements were interpreted to ahow that the exchange produces an additional solid phase, SrTiO/sub 3/, rather than the mixed phase, or solid solution, thatmore » ndght have been expected. The significance of this observation is discussed. The self-exchange of yttnium ions between a solid compound of yttrium and an alkali chloride flux in which yttrium chloride is dissolved appears in the systems studied to depend primaaily on the solubility of the solid. Exchange is rapid and complete in the case of yttrium oxychlonide, which is soluble to the extent of 0.6%, but is limited to the surface of yttrium chromium oxide, which has no measurable solubility in the flux. The introduction of yttrium ion vacancies in the lattice of yttrium chromium oxide has no detectable effect in promoting exchange. (For preceding period see NYO-3279.) (auth)« less

Key characteristics of knowledge transfer and exchange in healthcare: integrative literature review.

PubMed

Pentland, Duncan; Forsyth, Kirsty; Maciver, Donald; Walsh, Mike; Murray, Richard; Irvine, Linda; Sikora, Simon

2011-07-01

This paper presents the results of a review of literature relating to knowledge transfer and exchange in healthcare. Treatment, planning and policy decisions in contemporary nursing and healthcare should be based on sound evidence wherever possible, but research knowledge remains generally underused. Knowledge transfer and exchange initiatives aim to facilitate the accessibility, application and production of evidence and may provide solutions to this challenge. This review was conducted to help inform the design and implementation of knowledge transfer and exchange activities for a large healthcare organization. Databases: ASSIA, Business Source Premier, CINAHL, PsychInfo, Medline and the Cochrane Database of Systematic Reviews. An integrative literature review was carried out including an extensive literature search. English language systematic reviews, literature reviews, primary quantitative and qualitative papers and grey literature of high relevance evaluating, describing or discussing knowledge transfer or exchange activities in healthcare were included for review (January 1990-September 2009). Thirty-three papers were reviewed (four systematic reviews, nine literature reviews, one environmental scan, nine empirical studies and ten case studies). Robust research into knowledge transfer and exchange in healthcare is limited. Analysis of a wide range of evidence indicates a number of commonly featured characteristics but further evaluation of these activities would benefit their application in facilitating evidence-based practice in nursing. © 2011 The Authors. Journal of Advanced Nursing © 2011 Blackwell Publishing Ltd.

Effect of humidity on posterior lens opacification during fluid-air exchange.

PubMed

Harlan, J B; Lee, E T; Jensen, P S; de Juan, E

1999-06-01

To study the relationship of humidity and the rate of lens opacity formation during fluid-air exchange using an animal model. Vitrectomy and fluid-air exchange was carried out using 16 eyes of 8 pigmented rabbits. One eye of each rabbit was exposed to dry air and the fellow eye received humidified air using an intraocular air humidifier. In each case, the percent humidity of the intraocular air was measured using an in-line hygrometer. Elapsed time from initial air entry to lens feathering was recorded for each eye, with the surgeon-observer unaware of the percent humidity of the air infusion. In each rabbit, use of humidified air resulted in a delay in lens feathering (P<.02), with an overall increase in time to feathering of 80% for humidified air vs room air. Use of a humidifier during fluid-air exchange prolongs intraoperative lens clarity in the rabbit model, suggesting that humidified air should prolong lens clarity during phakic fluid-air exchange in patients. Use of humidified air during vitrectomy and fluid-air exchange may retard the intraoperative loss of lens clarity, promoting better visualization of the posterior segment and enhancing surgical performance.

Nuclear code case development of printed-circuit heat exchangers with thermal and mechanical performance testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aakre, Shaun R.; Jentz, Ian W.; Anderson, Mark H.

The U.S. Department of Energy has agreed to fund a three-year integrated research project to close technical gaps involved with compact heat exchangers to be used in nuclear applications. This paper introduces the goals of the project, the research institutions, and industrial partners working in collaboration to develop a draft Boiler and Pressure Vessel Code Case for this technology. Heat exchanger testing, as well as non-destructive and destructive evaluation, will be performed by researchers across the country to understand the performance of compact heat exchangers. Testing will be performed using coolants and conditions proposed for Gen IV Reactor designs. Preliminarymore » observations of the mechanical failure mechanisms of the heat exchangers using destructive and non-destructive methods is presented. Unit-cell finite element models assembled to help predict the mechanical behavior of these high-temperature components are discussed as well. Performance testing methodology is laid out in this paper along with preliminary modeling results, an introduction to x-ray and neutron inspection techniques, and results from a recent pressurization test of a printed-circuit heat exchanger. The operational and quality assurance knowledge gained from these models and validation tests will be useful to developers of supercritical CO 2 systems, which commonly employ printed-circuit heat exchangers.« less

The effect of the EU tissues and cells directive on bone banking in Denmark: a case study.

PubMed

Birk, Sofie Okkels; Hoeyer, Klaus

2010-08-01

As a result of the EU Tissues and Cells Directive (2004/23/EC), therapeutic tissue banking is currently being restructured throughout Europe. The stated objectives are to enhance a safe and stable supply of bone and tissue in Europe and to facilitate internal exchange. We conducted an interview study to explore the effect of the Directive on Danish bone banks in terms of (1) organizational restructuring, (2) supply and range of exchange, (3) economic costs. We found that the Directive stimulated extensive re-organization of bone banks with a substantial adjoining workload; that it is doubtful whether it will increase supply and range of exchange; and that the transposition of the Directive is associated with considerable extra cost. Additionally, we found that elements in the documentation of safety were fabricated by surgeons to avoid what was seen as unnecessary questioning of potential donors.

Conductance spectra of asymmetric ferromagnet/ferromagnet/ferromagnet junctions

NASA Astrophysics Data System (ADS)

Pasanai, K.

2017-01-01

A theory of tunneling spectroscopy of ferromagnet/ferromagnet/ferromagnet junctions was studied. We applied a delta-functional approximation for the interface scattering properties under a one-dimensional system of a free electron approach. The reflection and transmission probabilities were calculated in the ballistic regime, and the conductance spectra were then calculated using the Landauer formulation. The magnetization directions were set to be either parallel (P) or anti-parallel (AP) alignments, for comparison. We found that the conductance spectra was suppressed when increasing the interfacial scattering at the interfaces. Moreover, the electron could exhibit direct transmission when the thickness was rather thin. Thus, there was no oscillation in this case. However, in the case of a thick layer the conductance spectra oscillated, and this oscillation was most prominent when the middle layer thickness increased. In the case of direct transmission, the conductance spectra of P and AP systems were definitely suppressed with increased exchange energy of the middle ferromagnet. This also refers to an increase in the magnetoresistance of the junction. In the case of oscillatory behavior, the positions of the resonance peaks were changed as the exchange energy was changed.

Glove and gown effects on intraoperative bacterial contamination.

PubMed

Ward, William G; Cooper, Joshua M; Lippert, Dylan; Kablawi, Rawan O; Neiberg, Rebecca H; Sherertz, Robert J

2014-03-01

Experiments were performed to determine the risk of bacterial contamination associated with changing outer gloves and using disposable spunlace paper versus reusable cloth gowns. Despite decades of research, there remains a lack of consensus regarding certain aspects of optimal aseptic technique including outer glove exchange while double-gloving and surgical gown type selection. In an initial glove study, 102 surgical team members were randomized to exchange or retain outer gloves 1 hour into clean orthopedic procedures; cultures were obtained 15 minutes later from the palm of the surgeon's dominant gloved hand and from the surgical gown sleeve. Surgical gown type selection was recorded. A laboratory strike-through study investigating bacterial transmission through cloth and paper gowns was performed with coagulase-negative staphylococci. In a follow-up glove study, 251 surgical team members, all wearing paper gowns, were randomized as in the first glove study. Glove study 1 revealed 4-fold higher levels of baseline bacterial contamination (31% vs 7%) on the sleeve of surgical team members wearing cloth gowns than those using paper gowns [odds ratio (95% confidence interval): 4.64 (1.72-12.53); P = 0.0016]. The bacterial strike-through study revealed that 26 of 27 cloth gowns allowed bacterial transmission through the material compared with 0 of 27 paper gowns (P < 0.001). In glove study 2, surgeons retaining outer gloves 1 hour into the case had a subsequent positive glove contamination rate of 23% compared with 13% among surgeons exchanging their original outer glove [odds ratio (95% confidence interval): 1.97 (1.02-3.80); P = 0.0419]. Paper gowns demonstrated less bacterial transmission in the laboratory and lower rates of contamination in the operating room. Disposable paper gowns are recommended for all surgical cases, especially those involving implants, because of the heightened risk of infection. Outer glove exchange just before handling implant materials is also recommended to minimize intraoperative contamination.

Barriers and facilitators to exchanging health information: a systematic review.

PubMed

Eden, Karen B; Totten, Annette M; Kassakian, Steven Z; Gorman, Paul N; McDonagh, Marian S; Devine, Beth; Pappas, Miranda; Daeges, Monica; Woods, Susan; Hersh, William R

2016-04-01

We conducted a systematic review of studies assessing facilitators and barriers to use of health information exchange (HIE). We searched MEDLINE, PsycINFO, CINAHL, and the Cochrane Library databases between January 1990 and February 2015 using terms related to HIE. English-language studies that identified barriers and facilitators of actual HIE were included. Data on study design, risk of bias, setting, geographic location, characteristics of the HIE, perceived barriers and facilitators to use were extracted and confirmed. Ten cross-sectional, seven multiple-site case studies, and two before-after studies that included data from several sources (surveys, interviews, focus groups, and observations of users) evaluated perceived barriers and facilitators to HIE use. The most commonly cited barriers to HIE use were incomplete information, inefficient workflow, and reports that the exchanged information that did not meet the needs of users. The review identified several facilitators to use. Incomplete patient information was consistently mentioned in the studies conducted in the US but not mentioned in the few studies conducted outside of the US that take a collective approach toward healthcare. Individual patients and practices in the US may exercise the right to participate (or not) in HIE which effects the completeness of patient information available to be exchanged. Workflow structure and user roles are key but understudied. We identified several facilitators in the studies that showed promise in promoting electronic health data exchange: obtaining more complete patient information; thoughtful workflow that folds in HIE; and inclusion of users early in implementation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Novel Method for Exchange of Impella Circulatory Assist Catheter: The "Trojan Horse" Technique.

PubMed

Phillips, Colin T; Tamez, Hector; Tu, Thomas M; Yeh, Robert W; Pinto, Duane S

2017-07-01

Patients with an indwelling Impella may require escalation of hemodynamic support or exchange to another circulatory assistance platform. As such, preservation of vascular access is preferable in cases where anticoagulation cannot be discontinued or to facilitate exchange to an alternative catheter or closure device. Challenges exist in avoiding bleeding and loss of wire access in these situations. We describe a single-access "Trojan Horse" technique that minimizes bleeding while maintaining arterial access for rapid exchange of this percutaneous ventricular assist device.

Differences in the mobility of Cd, Cu, Pb and Zn during composting of two types of household bio-waste collected in four seasons.

PubMed

Hanc, Ales; Szakova, Jirina; Ochecova, Pavla

2014-09-01

The objective of this study was to evaluate the mobility of Cd, Cu, Pb and Zn during 3 different compost aeration rates of household bio-waste, originating in urban settlement (U-bio-waste) and family house buildings (F-bio-waste). The first two weeks, when the thermophilic composting phase became, the highest decline of exchangeable content was recorded. After 12 weeks of composting, lower exchangeable content was found in the case of U-bio-waste composts than F-bio-waste composts, despite higher loss of fresh mass. The order of fractions in both final composts was as follows: residual>oxidizable>reducible>exchangeable. The exchangeable portion of total content in final composts decreased in this order: Zn (17%), Cd (11%), Pb (4%) and Cu (3%). Regarding the low exchangeable content of heavy metals and high-quality organic matter, these types of composts could be used not only as fertilizer, but for remediation of metals contaminated land. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cumulant expansions for measuring water exchange using diffusion MRI

NASA Astrophysics Data System (ADS)

Ning, Lipeng; Nilsson, Markus; Lasič, Samo; Westin, Carl-Fredrik; Rathi, Yogesh

2018-02-01

The rate of water exchange across cell membranes is a parameter of biological interest and can be measured by diffusion magnetic resonance imaging (dMRI). In this work, we investigate a stochastic model for the diffusion-and-exchange of water molecules. This model provides a general solution for the temporal evolution of dMRI signal using any type of gradient waveform, thereby generalizing the signal expressions for the Kärger model. Moreover, we also derive a general nth order cumulant expansion of the dMRI signal accounting for water exchange, which has not been explored in earlier studies. Based on this analytical expression, we compute the cumulant expansion for dMRI signals for the special case of single diffusion encoding (SDE) and double diffusion encoding (DDE) sequences. Our results provide a theoretical guideline on optimizing experimental parameters for SDE and DDE sequences, respectively. Moreover, we show that DDE signals are more sensitive to water exchange at short-time scale but provide less attenuation at long-time scale than SDE signals. Our theoretical analysis is also validated using Monte Carlo simulations on synthetic structures.

Testing the limits of freedom of contract: the commercialization of reproductive materials and services.

PubMed

Trebilcock, M; Martin, M; Lawson, A; Lewis, P

1994-01-01

This article examines the cases for and against commercializing, or "commodifying," reproductive materials and services. Using a supply/demand third-party framework, three basic scenarios in which commercial-exchange relationships may be possible--exchange of gametes and zygotes, exchange of gestational services, and exchange of fetal material--and the major parties of interest, or stakeholders, are identified. The study sketches the liberal, essentialist, and radical contingency theories that shape the debate over the commercialization of reproductive materials and services. The article then attempts to derive some basic governing principles that reflect as much common ground as possible amongst these various normative perspectives, while recognizing that complete reconciliation is impossible. Taken together, these principles are designed to reflect a strategy of "constrained commodification," where commercialization or commodification, that is, financial remuneration, plays a relatively neutral role in the utilization of reproductive materials and services. In light of these principles, the article concludes by sketching legal and regulatory regimes with respect to the exchange of gametes and zygotes, gestational services, and fetal tissue.

The Washington Needle Depot: fitting healthcare to injection drug users rather than injection drug users to healthcare: moving from a syringe exchange to syringe distribution model

PubMed Central

2010-01-01

Needle exchange programs chase political as well as epidemiological dragons, carrying within them both implicit moral and political goals. In the exchange model of syringe distribution, injection drug users (IDUs) must provide used needles in order to receive new needles. Distribution and retrieval are co-existent in the exchange model. Likewise, limitations on how many needles can be received at a time compel addicts to have multiple points of contact with professionals where the virtues of treatment and detox are impressed upon them. The centre of gravity for syringe distribution programs needs to shift from needle exchange to needle distribution, which provides unlimited access to syringes. This paper provides a case study of the Washington Needle Depot, a program operating under the syringe distribution model, showing that the distribution and retrieval of syringes can be separated with effective results. Further, the experience of IDUs is utilized, through paid employment, to provide a vulnerable population of people with clean syringes to prevent HIV and HCV. PMID:20047690

77 FR 12624 - Self-Regulatory Organizations; NASDAQ OMX PHLX LLC; Notice of Filing and Immediate Effectiveness...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-01

... Exchange in routing to away markets. While changes to the Fee Schedule pursuant to this proposal are... orders to away markets. The Exchange currently assesses the following Routing Fees: Exchange Customer.... Each time NOS routes to away markets NOS is charged a $0.06 clearing fee and, in the case of certain...

Implementing Information and Communication Technology to Support Community Aged Care Service Integration: Lessons from an Australian Aged Care Provider.

PubMed

Douglas, Heather E; Georgiou, Andrew; Tariq, Amina; Prgomet, Mirela; Warland, Andrew; Armour, Pauline; Westbrook, Johanna I

2017-04-10

There is limited evidence of the benefits of information and communication technology (ICT) to support integrated aged care services. We undertook a case study to describe carelink+, a centralised client service management ICT system implemented by a large aged and community care service provider, Uniting. We sought to explicate the care-related information exchange processes associated with carelink+ and identify lessons for organisations attempting to use ICT to support service integration. Our case study included seventeen interviews and eleven observation sessions with a purposive sample of staff within the organisation. Inductive analysis was used to develop a model of ICT-supported information exchange. Management staff described the integrated care model designed to underpin carelink+. Frontline staff described complex information exchange processes supporting coordination of client services. Mismatches between the data quality and the functions carelink+ was designed to support necessitated the evolution of new work processes associated with the system. There is value in explicitly modelling the work processes that emerge as a consequence of ICT. Continuous evaluation of the match between ICT and work processes will help aged care organisations to achieve higher levels of ICT maturity that support their efforts to provide integrated care to clients.

Implementing Information and Communication Technology to Support Community Aged Care Service Integration: Lessons from an Australian Aged Care Provider

PubMed Central

Georgiou, Andrew; Tariq, Amina; Prgomet, Mirela; Warland, Andrew; Armour, Pauline; Westbrook, Johanna I

2017-01-01

Introduction: There is limited evidence of the benefits of information and communication technology (ICT) to support integrated aged care services. Objectives: We undertook a case study to describe carelink+, a centralised client service management ICT system implemented by a large aged and community care service provider, Uniting. We sought to explicate the care-related information exchange processes associated with carelink+ and identify lessons for organisations attempting to use ICT to support service integration. Methods: Our case study included seventeen interviews and eleven observation sessions with a purposive sample of staff within the organisation. Inductive analysis was used to develop a model of ICT-supported information exchange. Results: Management staff described the integrated care model designed to underpin carelink+. Frontline staff described complex information exchange processes supporting coordination of client services. Mismatches between the data quality and the functions carelink+ was designed to support necessitated the evolution of new work processes associated with the system. Conclusions: There is value in explicitly modelling the work processes that emerge as a consequence of ICT. Continuous evaluation of the match between ICT and work processes will help aged care organisations to achieve higher levels of ICT maturity that support their efforts to provide integrated care to clients. PMID:29042851

Basis of the tubesheet heat exchanger design rules used in the French pressure vessel code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Osweiller, F.

1992-02-01

For about 40 years most tubessheet exchangers have been designed according to the standards of TEMA. Partly due to their simplicity, these rules do not assure a safe heat-exchanger design in all cases. This is the main reason why new tubesheet design rules were developed in 1981 in France for the French pressure vessel code CODAP. For fixed tubesheet heat exchangers, the new rules account for the elastic rotational restraint of the shell and channel at the outer edge of the tubesheet, as proposed in 1959 by Galletly. For floating-head and U-tube heat exchangers, the approach developed by Gardner inmore » 1969 was selected with some modifications. In both cases, the tubesheet is replaced by an equivalent solid plate with adequate effective elastic constants, and the tube bundle is simulated by an elastic foundation. The elastic restraint at the edge of the tubesheet due the shell and channel is accounted for in different ways in the two types of heat exchangers. The purpose of the paper is to present the main basis of these rules and to compare them to TEMA rules.« less

Determination of association constants at moderately fast chemical exchange: complexation of camphor enantiomers by alpha-cyclodextrin.

PubMed

Bernatowicz, Piotr; Nowakowski, Michał; Dodziuk, Helena; Ejchart, Andrzej

2006-08-01

Association constants in weak molecular complexes can be determined by analysis of chemical shifts variations resulting from changes of guest to host concentration ratio. In the regime of very fast exchange, i.e., when exchange rate is several orders of magnitude larger than the Larmor angular frequency difference of the observed resonance in free and complexed molecule, the apparent position of averaged resonance is a population-weighted mean of resonances of particular forms involved in the equilibrium. The assumption of very fast exchange is often, however, tacitly admitted in literature even in cases where the process of interest is much slower than required. We show that such an unjustified simplification may, under certain circumstances, lead to significant underestimation of association constant and, in consequence, to non-negligible errors in Gibbs free energy under determination. We present a general method, based on iterative numerical NMR line shape analysis, which allows one for the compensation of chemical exchange effects, and delivers both the correct association constants and the exchange rates. The latter are not delivered by the other mentioned method. Practical application of our algorithm is illustrated by the case of camphor-alpha-cyclodextrin complexes.

Fluid Transport in Porous Media probed by Relaxation-Exchange NMR

NASA Astrophysics Data System (ADS)

Olaru, A. M.; Kowalski, J.; Sethi, V.; Blümich, B.

2011-12-01

The characterization of fluid transport in porous media represents a matter of high interest in fields like the construction industry, oil exploitation, and soil science. Moisture migration or flow at low rates, such as those occurring in soil during rain are difficult to characterize by classical high-field NMR velocimetry due to the dedicated hardware and elaborate techniques required for adequate signal encoding. The necessity of field studies raises additional technical problems, which can be solved only by the use of portable low-field NMR instruments. In this work we extend the use of low-field relaxation exchange experiments from the study of diffusive transport to that of advection. Relaxation exchange experiments were performed using a home-built Halbach magnet on model porous systems with controlled pore-size distributions and on natural porous systems (quartz sand with a broad pore-size distribution) exposed to unidirectional flow. Different flow rates leave distinctive marks on the exchange maps obtained by inverse Laplace transformation of the time domain results, due to the superposition of exchange, diffusion and inflow/outflow in multiple relaxation sites of the liquids in the porous media. In the case of slow velocities there is no loss of signal due to outflow, and the relaxation-exchange effects prevail, leading to a tilt of the diagonal distribution around a pivot point with increasing mixing time. The tilt suggests an asymmetry in the exchange between relaxation sites of large and small decay rates. Another observed phenomenon is the presence of a bigger number of exchange cross-peaks compared to the exchange maps obtained for the same systems in zero-flow conditions. We assume that this is due to enhanced exchange caused by the superposition of flow. For high velocities the outflow effects dominate and the relaxation-time distribution collapses towards lower values of the average relaxation times. In both cases the pore-size distribution has a strong effect on the results, the asymmetries being more obvious in the natural porous systems than in the glass bead packs used as models, while the enhanced exchange phenomenon appears predominantly in the maps obtained on the model systems. This is probably due to diffusion occurring in the presence of different internal field gradients. Shifts and tilts in the exchange maps can be simulated by solving the relaxation site-averaged Bloch-Torrey system forward in time and assuming an asymmetric closure for the transport, which might be realistic for preferential flow phenomena or for pore-size distributions with two or more clearly distinct pore size classes. When comparing the simulations results with the experimental data we observed a correspondence of signal collapse and translation towards lower relaxation times. The asymmetries could be qualitatively reproduced by making further assumptions on the pore structure, but further work is required to characterize and model the physical phenomenon behind. The results obtained reveal the possibility of characterizing advective fluid transport in porous systems by simple correlation experiments performed with inexpensive and mobile hardware.

Refractive outcomes after multifocal intraocular lens exchange.

PubMed

Kim, Eric J; Sajjad, Ahmar; Montes de Oca, Ildamaris; Koch, Douglas D; Wang, Li; Weikert, Mitchell P; Al-Mohtaseb, Zaina N

2017-06-01

To evaluate the refractive outcomes after multifocal intraocular lens (IOL) exchange. Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA. Retrospective case series. Patients had multifocal IOL explantation followed by IOL implantation. Outcome measures included type of IOL, surgical indication, corrected distance visual acuity (CDVA), and refractive prediction error. The study comprised 29 patients (35 eyes). The types of IOLs implanted after multifocal IOL explantation included in-the-bag IOLs (74%), iris-sutured IOLs (6%), sulcus-fixated IOLs with optic capture (9%), sulcus-fixated IOLs without optic capture (9%), and anterior chamber IOLs (3%). The surgical indication for exchange included blurred vision (60%), photic phenomena (57%), photophobia (9%), loss of contrast sensitivity (3%), and multiple complaints (29%). The CDVA was 20/40 or better in 94% of eyes before the exchange and 100% of eyes after the exchange (P = .12). The mean refractive prediction error significantly decreased from 0.22 ± 0.81 diopter (D) before the exchange to -0.09 ± 0.53 D after the exchange (P < .05). The median absolute refractive prediction error significantly decreased from 0.43 D before the exchange to 0.23 D after the exchange (P < .05). Multifocal IOL exchange can be performed safely with good visual outcomes using different types of IOLs. A lower refractive prediction error and a higher likelihood of 20/40 or better vision can be achieved with the implantation of the second IOL compared with the original multifocal IOL, regardless of the final IOL position. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

The time-dependence of exchange-induced relaxation during modulated radio frequency pulses.

PubMed

Sorce, Dennis J; Michaeli, Shalom; Garwood, Michael

2006-03-01

The problem of the relaxation of identical spins 1/2 induced by chemical exchange between spins with different chemical shifts in the presence of time-dependent RF irradiation (in the first rotating frame) is considered for the fast exchange regime. The solution for the time evolution under the chemical exchange Hamiltonian in the tilted doubly rotating frame (TDRF) is presented. Detailed derivation is specified to the case of a two-site chemical exchange system with complete randomization between jumps of the exchanging spins. The derived theory can be applied to describe the modulation of the chemical exchange relaxation rate constants when using a train of adiabatic pulses, such as the hyperbolic secant pulse. Theory presented is valid for quantification of the exchange-induced time-dependent rotating frame longitudinal T1rho,ex and transverse T2rho,ex relaxations in the fast chemical exchange regime.

Characterizing the Networks of Digital Information that Support Collaborative Adaptive Forest Management in Sierra Nevada Forests.

PubMed

Lei, Shufei; Iles, Alastair; Kelly, Maggi

2015-07-01

Some of the factors that can contribute to the success of collaborative adaptive management--such as social learning, open communication, and trust--are built upon a foundation of the open exchange of information about science and management between participants and the public. Despite the importance of information transparency, the use and flow of information in collaborative adaptive management has not been characterized in detail in the literature, and currently there exist opportunities to develop strategies for increasing the exchange of information, as well as to track information flow in such contexts. As digital information channels and networks have been increased over the last decade, powerful new information monitoring tools have also been evolved allowing for the complete characterization of information products through their production, transport, use, and monitoring. This study uses these tools to investigate the use of various science and management information products in a case study--the Sierra Nevada Adaptive Management Project--using a mixed method (citation analysis, web analytics, and content analysis) research approach borrowed from the information processing and management field. The results from our case study show that information technologies greatly facilitate the flow and use of digital information, leading to multiparty collaborations such as knowledge transfer and public participation in science research. We conclude with recommendations for expanding information exchange in collaborative adaptive management by taking advantage of available information technologies and networks.

The Power of a Question: A Case Study of Two Organizational Knowledge Capture Systems

NASA Technical Reports Server (NTRS)

Cooper, Lynn P.

2003-01-01

This document represents a presentation regarding organizational knowledge capture systems which was delivered at the HICSS-36 conference held from January 6-9, 2003. An exploratory case study of two knowledge resources is offered. Then, two organizational knowledge capture systems are briefly described: knowledge transfer from practitioner and the use of questions to represent knowledge. Finally, the creation of a database of peer review questions is suggested as a method of promoting organizational discussions and knowledge representation and exchange.

Is the "sterile cockpit" concept applicable to cardiovascular surgery critical intervals or critical events? The impact of protocol-driven communication during cardiopulmonary bypass.

PubMed

Wadhera, Rishi K; Parker, Sarah Henrickson; Burkhart, Harold M; Greason, Kevin L; Neal, James R; Levenick, Katherine M; Wiegmann, Douglas A; Sundt, Thoralf M

2010-02-01

There is general enthusiasm for applying strategies from aviation directly to medical care; the application of the "sterile cockpit" rule to surgery has accordingly been suggested. An implicit prerequisite to the evidence-based transfer of such a concept to the clinical domain, however, is definition of periods of high mental workload analogous to takeoff and landing. We measured cognitive demands among operating room staff, mapped critical events, and evaluated protocol-driven communication. With the National Aeronautics and Space Administration Task Load Index and semistructured focus groups, we identified common critical stages of cardiac surgical cases. Intraoperative communication was assessed before (n = 18) and after (n = 16) introduction of a structured communication protocol. Cognitive workload measures demonstrated high temporal diversity among caregivers in various roles. Eight critical events during cardiopulmonary bypass were then defined. A structured, unambiguous verbal communication protocol for these events was then implemented. Observations of 18 cases before implementation including 29.6 hours of cardiopulmonary bypass with 632 total communication exchanges (average 35.1 exchanges/case) were compared with observations of 16 cases after implementation including 23.9 hours of cardiopulmonary bypass with 748 exchanges (average 46.8 exchanges/case, P = .06). Frequency of communication breakdowns per case decreased significantly after implementation (11.5 vs 7.3 breakdowns/case, P = .008). Because of wide variations is cognitive workload among caregivers, effective communication can be structured around critical events rather than defined intervals analogous to the sterile cockpit, with reduction in communication breakdowns. 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Düchs, Dominik; Delaney, Kris T., E-mail: kdelaney@mrl.ucsb.edu; Fredrickson, Glenn H., E-mail: ghf@mrl.ucsb.edu

Field-theoretic models have been used extensively to study the phase behavior of inhomogeneous polymer melts and solutions, both in self-consistent mean-field calculations and in numerical simulations of the full theory capturing composition fluctuations. The models commonly used can be grouped into two categories, namely, species models and exchange models. Species models involve integrations of functionals that explicitly depend on fields originating both from species density operators and their conjugate chemical potential fields. In contrast, exchange models retain only linear combinations of the chemical potential fields. In the two-component case, development of exchange models has been instrumental in enabling stable complexmore » Langevin (CL) simulations of the full complex-valued theory. No comparable stable CL approach has yet been established for field theories of the species type. Here, we introduce an extension of the exchange model to an arbitrary number of components, namely, the multi-species exchange (MSE) model, which greatly expands the classes of soft material systems that can be accessed by the complex Langevin simulation technique. We demonstrate the stability and accuracy of the MSE-CL sampling approach using numerical simulations of triblock and tetrablock terpolymer melts, and tetrablock quaterpolymer melts. This method should enable studies of a wide range of fluctuation phenomena in multiblock/multi-species polymer blends and composites.« less

Green Synthesis of ZnO Nanoparticles by an Alginate Mediated Ion-Exchange Process and a case study for Photocatalysis of Methylene Blue Dye

NASA Astrophysics Data System (ADS)

Keong, Choo Cheng; Sunitha Vivek, Yamini; Salamatinia, Babak; Amini Horri, Bahman

2017-04-01

In this study, zinc oxide (ZnO) was prepared via extrusion-dripping method through an ion exchange mediated process using sodium alginate. The samples were synthesized at 500 °C and 600 °C to study the effect of calcination temperature. The morphology, microstructure and optical activity of the calcined ZnO nanoparticles were analyzed by TGA, FESEM and XRD. It was found that ZnO nanoparticles synthesized at 600 °C was of higher purity with high crystallinity. To enhance the photocatalytic efficiency of zinc oxide, ZnO/NCC films were synthesized at varying ZnO loading fractions of 10 wt%, 15 wt%, 20 wt% and 25 wt% and were evaluated by photodegradation of Methylene blue dye and the highest dye percentage removal is found to be 96% which is obtained at ZnO loadings of 25 wt%. The usage of ion-exchange process has shown promising results in producing ZnO of desirable characteristics.

Monte Carlo Study of Magnetic Properties of Mixed Spins in a Fullerene X 30 Y 30-Like Structure

NASA Astrophysics Data System (ADS)

Mhirech, A.; Aouini, S.; Alaoui-Ismaili, A.; Bahmad, L.

2018-03-01

In this work, inspiring form of the fullerene-C60 structures, we study the mixed X_{30} Y_{30} fullerene-like structure and investigate its magnetic properties. In a such a structure, the carbons are assumed to be replaced by magnetic atoms having spin moments σ = 1/2 and S = 1. Firstly, we elaborate the ground-state phase diagrams in different physical parameter planes. In a second stage, we investigate the exchange coupling interaction effects in the absence or presence of both external magnetic and crystal fields. Using the Monte Carlo method, we carried out a study of the system magnetic properties and the thermal behavior of such a system for the ferromagnetic case. It is found that the critical temperature increases when increasing the coupling exchange interactions. On the other hand, the coercive magnetic field increases also when increasing the coupling exchange interactions. However, this physical parameter decreases when increasing the reduced temperature.

Broadening Student Learning Experiences via a Novel Cross-Disciplinary Art and Anatomy Education Program--A Case Study

ERIC Educational Resources Information Center

Speed, Caroline J.; Kleiner, Adina; Macaulay, Janet O.

2015-01-01

This study explored student learning and engagement in a novel cross-disciplinary education program, in particular whether medical students learning experiences can be enhanced through interaction and exchange of knowledge with students of varying disciplines. The program, entitled AnaRtomy, studies the historical relationship between art and…

Wiki as a Corporate Learning Tool: Case Study for Software Development Company

ERIC Educational Resources Information Center

Milovanovic, Milos; Minovic, Miroslav; Stavljanin, Velimir; Savkovic, Marko; Starcevic, Dusan

2012-01-01

In our study, we attempted to further investigate how Web 2.0 technologies influence workplace learning. Our particular interest was on using Wiki as a tool for corporate exchange of knowledge with the focus on informal learning. In this study, we collaborated with a multinational software development company that uses Wiki as a corporate tool…

Successful management of neonatal hemochromatosis by exchange transfusion and immunoglobulin: a case report.

PubMed

Babor, F; Hadzik, B; Stannigel, H; Mayatepek, E; Hoehn, T

2013-01-01

Neonatal hemochromatosis (NH) is a rare and severe liver disease of mainly intra-uterine onset, characterized by neonatal liver failure, hepatic and extrahepatic iron accumulation. This leads to an altered iron metabolism with resulting siderosis. The disease represents the most common cause of liver failure in neonates and is also the most common indication for neonatal liver transplantation. We present a case of a newborn diagnosed with NH and life threatening liver failure. Initial treatment consisted of chelation therapy and antioxidants, but lack of laboratory and clinical improvement led to an exchange transfusion followed by the singular substitution of intravenous immunoglobulin (IVIG). Both, exchange transfusion and IVIG were tolerated well and led to an improvement of the general condition of the patient and recovery of liver synthetic function. The subsequent favorable course of the disease is described in this case report.

Intensification of ammonia removal from waste water in biologically active zeolitic ion exchange columns.

PubMed

Almutairi, Azel; Weatherley, Laurence R

2015-09-01

The use of nitrification filters for the removal of ammonium ion from waste-water is an established technology deployed extensively in municipal water treatment, in industrial water treatment and in applications such as fish farming. The process involves the development of immobilized bacterial films on a solid packing support, which is designed to provide a suitable host for the film, and allow supply of oxygen to promote aerobic action. Removal of ammonia and nitrite is increasingly necessary to meet drinking water and discharge standards being applied in the US, Europe and other places. Ion-exchange techniques are also effective for removal of ammonia (as the ammonium ion) from waste water and have the advantage of fast start-up times compared to biological filtration which in some cases may take several weeks to be fully operational. Here we explore the performance of ion exchange columns in which nitrifying bacteria are cultivated, with the goal of a "combined" process involving simultaneous ion-exchange and nitrification, intensified by in-situ aeration with a novel membrane module. There were three experimental goals. Firstly, ion exchange zeolites were characterized and prepared for comparative column breakthrough studies for ammonia removal. Secondly effective in-situ aeration for promotion of nitrifying bacterial growth was studied using a number of different membranes including polyethersulfone (PES), polypropylene (PP), nylon, and polytetra-fluoroethylene (PTFE). Thirdly the breakthrough performance of ion exchange columns filled with zeolite in the presence of aeration and in the presence of nitrifying bacteria was determined to establish the influence of biomass, and aeration upon breakthrough during ammonium ion uptake. The methodology adopted included screening of two types of the naturally occuring zeolite clinoptilolite for effective ammonia removal in continuous ion-exchange columns. Next, the performance of fixed beds of clinoptilolite in the presence of nitrifying bacteria is compared to that in columns in which only ion exchange is occurring. The aeration performance of each of the chosen membranes was compared experimentally using a newly developed membrane support module which is also described. Comparison of ammonia removal in columns equipped with in-situ aeration using each membrane was undertaken and the breakthrough characteristics determined. The results showed that ammonia removal in the presence of the nitrifiers was significantly intensified. Column operation with membrane aeration showed further enhancement of ammonia removal. The greatest enhancement was observed in the case of the polyethersulfone membrane (PES). It is concluded that combined nitrification and ion-exchange is significantly intensified in packed columns by in-situ aeration using a novel membrane module. There is significant potential for extending the ion-exchange cycle time and thus potential cost reduction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Combining Vocational and Higher Education Studies to Provide Dual Parallel Qualifications--An Australian Case Study

ERIC Educational Resources Information Center

McLaughlin, Patricia; Mills, Anthony

2011-01-01

Developing academic relationships between vocational colleges and universities in Australia has been problematic, with exchanges between the two sectors limited to linear articulation and prescribed credit transfer. Whilst some very good examples of collaboration exist, the two sectors generally operate independently of each other. The isolation…

Crossover between collective and independent-particle excitations in quasi-2D electron gas with one filled subband

NASA Astrophysics Data System (ADS)

Nazarov, Vladimir U.

2018-05-01

While it has been recently demonstrated that, for quasi-two-dimensional electron gas (Q2DEG) with one filled subband, the dynamic exchange f x and Hartree f H kernels cancel each other in the low-density regime r s → ∞ (by half and completely, for the spin-neutral and fully spin-polarized cases, respectively), here we analytically show that the same happens at arbitrary densities at short distances. This motivates us to study the confinement dependence of the excitations in Q2DEG. Our calculations unambiguously confirm that, at strong confinements, the time-dependent exact exchange excitation energies approach the single-particle Kohn-Sham ones for the spin-polarized case, while the same, but less pronounced, tendency is observed for spin-neutral Q2DEG.

Non-Abelian statistics of vortices with non-Abelian Dirac fermions.

PubMed

Yasui, Shigehiro; Hirono, Yuji; Itakura, Kazunori; Nitta, Muneto

2013-05-01

We extend our previous analysis on the exchange statistics of vortices having a single Dirac fermion trapped in each core to the case where vortices trap two Dirac fermions with U(2) symmetry. Such a system of vortices with non-Abelian Dirac fermions appears in color superconductors at extremely high densities and in supersymmetric QCD. We show that the exchange of two vortices having doublet Dirac fermions in each core is expressed by non-Abelian representations of a braid group, which is explicitly verified in the matrix representation of the exchange operators when the number of vortices is up to four. We find that the result contains the matrices previously obtained for the vortices with a single Dirac fermion in each core as a special case. The whole braid group does not immediately imply non-Abelian statistics of identical particles because it also contains exchanges between vortices with different numbers of Dirac fermions. However, we find that it does contain, as its subgroup, genuine non-Abelian statistics for the exchange of the identical particles, that is, vortices with the same number of Dirac fermions. This result is surprising compared with conventional understanding because all Dirac fermions are defined locally at each vortex, unlike the case of Majorana fermions for which Dirac fermions are defined nonlocally by Majorana fermions located at two spatially separated vortices.

NUCLEAR POWER INSTALLATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bell, F.R.

1962-12-01

An arrangement is described for nuclear power plants including a reactor and at least one heat exchanger having primary and secondary circuits through which are passed heat-conveying fluids. Pressure-resisting walls about the heat exchangers and the reactor are either integral with or rigidly connected to one another. The heat exchangers are arranged so that their casings tend to shield withdrawn control rods from damage by radiation. (R.J.S.)

Exchange transfusion can be life-saving in severe propanil poisoning: a case report.

PubMed

Ranasinghe, Priyanga; Dilrukshi, Shani Apsara; Atukorala, Inoshi; Katulanda, Prasad; Gnanathasan, Ariaranee

2014-10-08

Propanil is an important cause of herbicide poisoning in Sri Lanka, accounting for about 2% of all cases of self-poisoning. The outcome is extremely poor when the poisoning is severe and current medical care is of limited efficacy. Death usually occurs due to the severe and prolonged methaemoglobinaemia. We describe a case of severe Propanil poisoning, successfully treated by exchange transfusion at a tertiary care hospital in Sri Lanka. A 17-year old Sri Lankan male (body weight--42 kg), presented to a local hospital 1 hour after self-ingestion of nearly 500 ml (4.3 g/kg) of liquid Propanil (concentration--360 g/l). On admission he had dizziness and peripheral cyanosis. He was given intravenous methylene blue (1 mg/kg) within one hour of admission, which was repeated subsequently due to minimal response. The next day morning, (18 hours after poisoning) the patient was transferred to the National Hospital of Sri Lanka (NHSL) for further management. On admission to NHSL, he was drowsy and confused, had a shallow respiratory effort and marked central and peripheral cyanosis. Respiratory rate was 20/min, with a pulse-oximetry of 77% on room air. The arterial blood gas analysis was as follows; pH--7.24, HCO3(-)--12 mmol/l, pCO2--28 mmHg, pO2--239 mmHg and O2 saturation--100%. Exchange transfusion was commenced within two hours of admission to NHSL. A dramatic improvement in oxygen saturation was observed immediately afterwards, with the saturation in pulse-oximetry rising to >95%. The level of consciousness and respiratory effort also improved. He was discharged subsequently 8 days after the initial poisoning. Propanil has potential to produce severe life threatening clinical manifestations, despite categorization as a herbicide with low toxicity. In cases of severe poisoning, exchange transfusion may be life saving. Since methylene blue, intensive care and exchange transfusion facilities are also not readily available in local hospitals, which frequently encounter cases of severe Propanil poisoning, early transfer of patients to tertiary care hospitals should be considered. Exchange transfusion may be helpful even in late stages in patients with severe poisoning.

MetaSeq: privacy preserving meta-analysis of sequencing-based association studies.

PubMed

Singh, Angad Pal; Zafer, Samreen; Pe'er, Itsik

2013-01-01

Human genetics recently transitioned from GWAS to studies based on NGS data. For GWAS, small effects dictated large sample sizes, typically made possible through meta-analysis by exchanging summary statistics across consortia. NGS studies groupwise-test for association of multiple potentially-causal alleles along each gene. They are subject to similar power constraints and therefore likely to resort to meta-analysis as well. The problem arises when considering privacy of the genetic information during the data-exchange process. Many scoring schemes for NGS association rely on the frequency of each variant thus requiring the exchange of identity of the sequenced variant. As such variants are often rare, potentially revealing the identity of their carriers and jeopardizing privacy. We have thus developed MetaSeq, a protocol for meta-analysis of genome-wide sequencing data by multiple collaborating parties, scoring association for rare variants pooled per gene across all parties. We tackle the challenge of tallying frequency counts of rare, sequenced alleles, for metaanalysis of sequencing data without disclosing the allele identity and counts, thereby protecting sample identity. This apparent paradoxical exchange of information is achieved through cryptographic means. The key idea is that parties encrypt identity of genes and variants. When they transfer information about frequency counts in cases and controls, the exchanged data does not convey the identity of a mutation and therefore does not expose carrier identity. The exchange relies on a 3rd party, trusted to follow the protocol although not trusted to learn about the raw data. We show applicability of this method to publicly available exome-sequencing data from multiple studies, simulating phenotypic information for powerful meta-analysis. The MetaSeq software is publicly available as open source.

Data Content and Exchange in General Practice: a Review

PubMed Central

Kalankesh, Leila R; Farahbakhsh, Mostafa; Rahimi, Niloofar

2014-01-01

Background: efficient communication of data is inevitable requirement for general practice. Any issue in data content and its exchange among GP and other related entities hinders continuity of patient care. Methods: literature search for this review was conducted on three electronic databases including Medline, Scopus and Science Direct. Results: through reviewing papers, we extracted information on the GP data content, use cases of GP information exchange, its participants, tools and methods, incentives and barriers. Conclusion: considering importance of data content and exchange for GP systems, it seems that more research is needed to be conducted toward providing a comprehensive framework for data content and exchange in GP systems. PMID:25648317

Metadata management and semantics in microarray repositories.

PubMed

Kocabaş, F; Can, T; Baykal, N

2011-12-01

The number of microarray and other high-throughput experiments on primary repositories keeps increasing as do the size and complexity of the results in response to biomedical investigations. Initiatives have been started on standardization of content, object model, exchange format and ontology. However, there are backlogs and inability to exchange data between microarray repositories, which indicate that there is a great need for a standard format and data management. We have introduced a metadata framework that includes a metadata card and semantic nets that make experimental results visible, understandable and usable. These are encoded in syntax encoding schemes and represented in RDF (Resource Description Frame-word), can be integrated with other metadata cards and semantic nets, and can be exchanged, shared and queried. We demonstrated the performance and potential benefits through a case study on a selected microarray repository. We concluded that the backlogs can be reduced and that exchange of information and asking of knowledge discovery questions can become possible with the use of this metadata framework.

Circles of Confidence in Correspondence: Modeling Confidentiality and Secrecy in Knowledge Exchange Networks of Letters and Drawings in the Early Modern Period.

PubMed

van den Heuvel, Charles; Weingart, Scott B; Spelt, Nils; Nellen, Henk

2016-01-01

Science in the early modern world depended on openness in scholarly communication. On the other hand, a web of commercial, political, and religious conflicts required broad measures of secrecy and confidentiality; similar measures were integral to scholarly rivalries and plagiarism. This paper analyzes confidentiality and secrecy in intellectual and technological knowledge exchange via letters and drawings. We argue that existing approaches to understanding knowledge exchange in early modern Europe--which focus on the Republic of Letters as a unified entity of corresponding scholars--can be improved upon by analyzing multilayered networks of communication. We describe a data model to analyze circles of confidence and cultures of secrecy in intellectual and technological knowledge exchanges. Finally, we discuss the outcomes of a first experiment focusing on the question of how personal and professional/official relationships interact with confidentiality and secrecy, based on a case study of the correspondence of Hugo Grotius.

Causes of Phakic Implantable Collamer Lens Explantation/Exchange at King Khaled Eye Specialist Hospital

PubMed Central

AlSabaani, Nasser A.; Behrens, Ashley; Jastanieah, Sabah; Al Malki, Salem; Al Jindan, Mohanna; Al Motowa, Saeed

2016-01-01

PURPOSE: The purpose of this study is to evaluate the causes of phakic implantable collamer lens (ICL) explantation/exchange at an eye hospital in Saudi Arabia. MATERIALS AND METHODS: A retrospective chart review was performed for patients who underwent ICL implantation from 2007 to March 2014 and data were collected on cases that underwent ICL explantation. RESULTS: Of the 787 ICL implants, 30 implants (3.8% [95% confidence interval 2.6%; 5.3%]) were explanted. The causes of explantation included incorrect lens size (22), cataract (4), high residual astigmatism (2), rhegmatogenous retinal detachment (1), and intolerable glare (1). Corrective measures mainly included an exchange with an appropriately sized lens (9), ICL explantation (11), with phacoemulsification and posterior chamber intraocular lens implantation (6), or replacement with an ICL of correct power (2). CONCLUSION: Incorrect ICL size was the most common cause of ICL explantation. More accurate sizing methods for ICL are required to reduce the explantation/exchange rate. PMID:27994391

Principals as Classroom Leaders

ERIC Educational Resources Information Center

Bunting, Carolyn

2007-01-01

The author suggests five ways in which busy principals can indirectly demonstrate their classroom leadership by encouraging teacher specialization, giving teachers opportunities to present case studies of at-risk students, building a diverse intellectual climate, instituting an idea exchange, and scheduling time for teachers to openly discuss a…

Apprenticeships and Community Colleges: Linkages in America's Defense.

ERIC Educational Resources Information Center

Cantor, Jeffrey A.

1994-01-01

Case studies of cooperative apprenticeships in Naval shipyards and maritime industries identify the benefits of mutual exchanges: access to external funds, appropriate mediation of conflicts, and models for formal contracts. Business-community college partnerships can learn from these examples how to establish working relationships for…

Suitability of the methylene blue test for determination of cation exchange capacity of clay minerals related to ammonium acetate method

NASA Astrophysics Data System (ADS)

Milošević, Maja; Logar, Mihovil; Dojčinović, Biljana; Erić, Suzana

2015-04-01

Cation exchange capacity (CEC) represents one of the most important parameters of clay minerals which reflects their ability to exchange cations with liquid phases in near contact. Measurement of CEC is used for characterizing sample plasticity, adsorbing and swelling properties which later define their usage in industrial purposes. Several methods have been developed over the years for determination of layer charge, charge density, charge distribution, etc. and have been published in numerous papers (Czimerova et al., 2006; Yukselen and Kaya, 2008). The main goal of present study is comparison of suitability of more recent method - methylene blue test in regard to older method - ammonium acetate for determination of CEC. For this study, we selected one montmorillonite clay (Bogovina, Serbia) and two mainly kaolinite clays (Miličinica, Serbia). Chemicals used for CEC determinations were solution of methylene blue (MB)(14*10-6M/ml) and ammonium acetate (AA) solution (1M). The obtained results are showing generally lower values in case of MB method. The main difference is due to molecular aggregation of MB on the clay surface. AA method is highly sensitive to the presence of CaO. Release of Ca ion from the sample into the solution can limit the saturation of exchange sites by the ammonium ion. This is clearly visible in case of montmorillonite clay. Fe2+ and Mg ions are difficult to move by the ammonium ion because of their ion radius, but in case of MB molecule there is no such restriction in removing them from the exchange sites. MB solution, even in a low concentration (2*10-6M/ml), is showing preferable results in moving the ions from their positions which is already visible after adding a small quantity of solution (25cm3). Both MB-titration and MB-spot test yield similar results and are much simpler methods than AA and they also give other information such as specific surface area (external and internal) whereas AA method only provides information about cations in exchangeable positions. Both methods, methylene blue test and ammonium acetate method, have advantages and disadvantages and differ in their requirements for the sample preparations but in general method selection is depending on the specific application of the given sample. References: - Yukselen, Y. and Kaya, A., Engineering Geology 102 (2008) 38-45 - Czimerova, A., Bujdak, J. and Dohrmann, R., Applied Clay Science 34 (2006) 2-13

Comparison of Analytical and Numerical Performance Predictions for an International Space Station Node 3 Internal Active Thermal Control System Regenerative Heat Exchanger

NASA Technical Reports Server (NTRS)

Wise, Stephen A.; Holt, James M.

2002-01-01

The complexity of International Space Station (ISS) systems modeling often necessitates the concurrence of various dissimilar, parallel analysis techniques to validate modeling. This was the case with a feasibility and performance study of the ISS Node 3 Regenerative Heat Exchanger (RHX). A thermo-hydraulic network model was created and analyzed in SINDA/FLUINT. A less complex, closed form solution of the systems dynamics was created using an Excel Spreadsheet. The purpose of this paper is to provide a brief description of the modeling processes utilized, the results and benefits of each to the ISS Node 3 RHX study.

Comparison of Analytical and Numerical Performance Predictions for a Regenerative Heat Exchanger in the International Space Station Node 3 Internal Active Thermal Control System

NASA Technical Reports Server (NTRS)

Wise, Stephen A.; Holt, James M.; Turner, Larry D. (Technical Monitor)

2001-01-01

The complexity of International Space Station (ISS) systems modeling often necessitates the concurrence of various dissimilar, parallel analysis techniques to validate modeling. This was the case with a feasibility and performance study of the ISS Node 3 Regenerative Heat Exchanger (RHX). A thermo-hydraulic network model was created and analyzed in SINDA/FLUINT. A less complex, closed form solution of the system dynamics was created using Excel. The purpose of this paper is to provide a brief description of the modeling processes utilized, the results and benefits of each to the ISS Node 3 RHX study.

Mercury poisoning through intravenous administration: Two case reports with literature review.

PubMed

Lu, Qiuying; Liu, Zilong; Chen, Xiaorui

2017-11-01

Metallic mercury poisoning through intravenous injection is rare, especially for a homicide attempt. Diagnosis and treatment of the disease are challenging. A 34-year-old male presented with pyrexia, chill, fatigue, body aches, and pain of the dorsal aspect of right foot. Another case is that of a 29-year-old male who committed suicide by injecting himself metallic mercury 15 g intravenously and presented with dizzy, dyspnea, fatigue, sweatiness, and waist soreness. The patient's condition in case 1 was deteriorated after initial treatment. Imaging studies revealed multiple high-density spots throughout the body especially in the lungs. On further questioning, the patient's girlfriend acknowledged that she injected him about 40 g mercury intravenously 11 days ago. The diagnosis was then confirmed with a urinary mercury concentration of 4828 mg/L. Surgical excision, continuous blood purification, plasma exchange, alveolar lavage, and chelation were performed successively in case 1. Blood irrigation and chelation therapy were performed in case 2. The laboratory test results and organ function of the patient in case 1 gradually returned to normal. However, in case 2, the patient's dyspnea was getting worse and he finally died due to toxic encephalopathy and respiratory failure. Early diagnosis and appropriate treatment are critical for intravenous mercury poisoning. It should be concerned about the combined use of chelation agents and other treatments, such as surgical excision, hemodialysis and plasma exchange in clinical settings.

Dynamic NMR under nonstationary conditions: Theoretical model, numerical calculation, and potential of application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Babailov, S. P., E-mail: babajlov@niic.nsc.ru; National Research Tomsk Polytechnic University, Lenin Avenue 30, Tomsk 634050; Purtov, P. A.

An expression has been derived for the time dependence of the NMR line shape for systems with multi-site chemical exchange in the absence of spin-spin coupling, in a zero saturation limit. The dynamics of variation of the NMR line shape with time is considered in detail for the case of two-site chemical exchange. Mathematical programs have been designed for numerical simulation of the NMR spectra of chemical exchange systems. The analytical expressions obtained are useful for NMR line shape simulations for systems with photoinduced chemical exchange.

Standardizing data exchange for clinical research protocols and case report forms: An assessment of the suitability of the Clinical Data Interchange Standards Consortium (CDISC) Operational Data Model (ODM).

PubMed

Huser, Vojtech; Sastry, Chandan; Breymaier, Matthew; Idriss, Asma; Cimino, James J

2015-10-01

Efficient communication of a clinical study protocol and case report forms during all stages of a human clinical study is important for many stakeholders. An electronic and structured study representation format that can be used throughout the whole study life-span can improve such communication and potentially lower total study costs. The most relevant standard for representing clinical study data, applicable to unregulated as well as regulated studies, is the Operational Data Model (ODM) in development since 1999 by the Clinical Data Interchange Standards Consortium (CDISC). ODM's initial objective was exchange of case report forms data but it is increasingly utilized in other contexts. An ODM extension called Study Design Model, introduced in 2011, provides additional protocol representation elements. Using a case study approach, we evaluated ODM's ability to capture all necessary protocol elements during a complete clinical study lifecycle in the Intramural Research Program of the National Institutes of Health. ODM offers the advantage of a single format for institutions that deal with hundreds or thousands of concurrent clinical studies and maintain a data warehouse for these studies. For each study stage, we present a list of gaps in the ODM standard and identify necessary vendor or institutional extensions that can compensate for such gaps. The current version of ODM (1.3.2) has only partial support for study protocol and study registration data mainly because it is outside the original development goal. ODM provides comprehensive support for representation of case report forms (in both the design stage and with patient level data). Inclusion of requirements of observational, non-regulated or investigator-initiated studies (outside Food and Drug Administration (FDA) regulation) can further improve future revisions of the standard. Published by Elsevier Inc.

Do Students Share the Same Experience in an Online Language Exchange Programme?--The Chinese-French eTandem Case

ERIC Educational Resources Information Center

Szilas, Jue Wang; Zhang, Ling; Berger, Claudia

2013-01-01

This article presents the findings of an eTandem Chinese-French exchange course during two academic years, the year 2010-2011 when the course was not credited, and the year 2011-2012 when the course was credited in one university but not in the other. It focuses on the students' perspective about the language exchange experience. The participants…

L2 Academic Discourse Socialization through Oral Presentations: An Undergraduate Student's Learning Trajectory in Study Abroad

ERIC Educational Resources Information Center

Kobayashi, Masaki

2016-01-01

The present study provides an in-depth, longitudinal account of an undergraduate student's L2 discourse socialization in an academic exchange program in Canada. By invoking Rogoff's (1995) notion of participatory appropriation, this qualitative case study examined an L2 student's task-related strategies and performance as they evolved over time in…

A critical review of period analyses and implications for mass exchange in W UMa eclipsing binaries: Paper 3

NASA Astrophysics Data System (ADS)

Nelson, R. H.; Terrell, D.; Milone, E. F.

2016-02-01

This is the third of a series of four papers, the goal of which is to identify the overcontact eclipsing binary star systems for which a solid case can be made for mass exchange. To reach this goal, it is necessary first to identify those systems for which there is a strong case for period change. We have identified 60 candidate systems; in the first two papers (Nelson et al. 2014, 2016) we discussed 40 individual cases; this paper continues with the last 20. For each system, we present a detailed discussion and evaluation concerning the observational and interpretive material presented in the literature. At least one eclipse timing (ET) diagram, commonly referred to as an "O-C diagram", that includes the latest available data, accompanies each discussion. In paper 4, we will discuss the mechanisms that can cause period change and which of the 60 systems can be reliably concluded to exhibit mass exchange; we will also provide a list of marginal and rejected cases - suitable for future work.

Interaction-Free Effects Between Distant Atoms

NASA Astrophysics Data System (ADS)

Aharonov, Yakir; Cohen, Eliahu; Elitzur, Avshalom C.; Smolin, Lee

2018-01-01

A Gedanken experiment is presented where an excited and a ground-state atom are positioned such that, within the former's half-life time, they exchange a photon with 50% probability. A measurement of their energy state will therefore indicate in 50% of the cases that no photon was exchanged. Yet other measurements would reveal that, by the mere possibility of exchange, the two atoms have become entangled. Consequently, the "no exchange" result, apparently precluding entanglement, is non-locally established between the atoms by this very entanglement. This quantum-mechanical version of the ancient Liar Paradox can be realized with already existing transmission schemes, with the addition of Bell's theorem applied to the no-exchange cases. Under appropriate probabilities, the initially-excited atom, still excited, can be entangled with additional atoms time and again, or alternatively, exert multipartite nonlocal correlations in an interaction free manner. When densely repeated several times, this result also gives rise to the Quantum Zeno effect, again exerted between distant atoms without photon exchange. We discuss these experiments as variants of interaction-free-measurement, now generalized for both spatial and temporal uncertainties. We next employ weak measurements for elucidating the paradox. Interpretational issues are discussed in the conclusion, and a resolution is offered within the Two-State Vector Formalism and its new Heisenberg framework.

Interaction-Free Effects Between Distant Atoms

NASA Astrophysics Data System (ADS)

Aharonov, Yakir; Cohen, Eliahu; Elitzur, Avshalom C.; Smolin, Lee

2017-12-01

A Gedanken experiment is presented where an excited and a ground-state atom are positioned such that, within the former's half-life time, they exchange a photon with 50% probability. A measurement of their energy state will therefore indicate in 50% of the cases that no photon was exchanged. Yet other measurements would reveal that, by the mere possibility of exchange, the two atoms have become entangled. Consequently, the "no exchange" result, apparently precluding entanglement, is non-locally established between the atoms by this very entanglement. This quantum-mechanical version of the ancient Liar Paradox can be realized with already existing transmission schemes, with the addition of Bell's theorem applied to the no-exchange cases. Under appropriate probabilities, the initially-excited atom, still excited, can be entangled with additional atoms time and again, or alternatively, exert multipartite nonlocal correlations in an interaction free manner. When densely repeated several times, this result also gives rise to the Quantum Zeno effect, again exerted between distant atoms without photon exchange. We discuss these experiments as variants of interaction-free-measurement, now generalized for both spatial and temporal uncertainties. We next employ weak measurements for elucidating the paradox. Interpretational issues are discussed in the conclusion, and a resolution is offered within the Two-State Vector Formalism and its new Heisenberg framework.

Comparison of two adaptive temperature-based replica exchange methods applied to a sharp phase transition of protein unfolding-folding.

PubMed

Lee, Michael S; Olson, Mark A

2011-06-28

Temperature-based replica exchange (T-ReX) enhances sampling of molecular dynamics simulations by autonomously heating and cooling simulation clients via a Metropolis exchange criterion. A pathological case for T-ReX can occur when a change in state (e.g., folding to unfolding of a protein) has a large energetic difference over a short temperature interval leading to insufficient exchanges amongst replica clients near the transition temperature. One solution is to allow the temperature set to dynamically adapt in the temperature space, thereby enriching the population of clients near the transition temperature. In this work, we evaluated two approaches for adapting the temperature set: a method that equalizes exchange rates over all neighbor temperature pairs and a method that attempts to induce clients to visit all temperatures (dubbed "current maximization") by positioning many clients at or near the transition temperature. As a test case, we simulated the 57-residue SH3 domain of alpha-spectrin. Exchange rate equalization yielded the same unfolding-folding transition temperature as fixed-temperature ReX with much smoother convergence of this value. Surprisingly, the current maximization method yielded a significantly lower transition temperature, in close agreement with experimental observation, likely due to more extensive sampling of the transition state.

Social marketing's unique contribution to mental health stigma reduction and HIV testing: two case studies.

PubMed

Thackeray, Rosemary; Keller, Heidi; Heilbronner, Jennifer Messenger; Dellinger, Laura K Lee

2011-03-01

Since its inception in 2005, articles in Health Promotion Practice's social marketing department have focused on describing social marketing's unique contributions and the application of each to the practice of health promotion. This article provides a brief review of six unique features (marketing mix, consumer orientation, segmentation, exchange, competition, and continuous monitoring) and then presents two case studies-one on reducing stigma related to mental health and the other a large-scale campaign focused on increasing HIV testing among African American youth. The two successful case studies show that social marketing principles can be applied to a wide variety of topics among various population groups.

Improving approximate-optimized effective potentials by imposing exact conditions: Theory and applications to electronic statics and dynamics

NASA Astrophysics Data System (ADS)

Kurzweil, Yair; Head-Gordon, Martin

2009-07-01

We develop a method that can constrain any local exchange-correlation potential to preserve basic exact conditions. Using the method of Lagrange multipliers, we calculate for each set of given Kohn-Sham orbitals a constraint-preserving potential which is closest to the given exchange-correlation potential. The method is applicable to both the time-dependent (TD) and independent cases. The exact conditions that are enforced for the time-independent case are Galilean covariance, zero net force and torque, and Levy-Perdew virial theorem. For the time-dependent case we enforce translational covariance, zero net force, Levy-Perdew virial theorem, and energy balance. We test our method on the exchange (only) Krieger-Li-Iafrate (xKLI) approximate-optimized effective potential for both cases. For the time-independent case, we calculated the ground state properties of some hydrogen chains and small sodium clusters for some constrained xKLI potentials and Hartree-Fock (HF) exchange. The results (total energy, Kohn-Sham eigenvalues, polarizability, and hyperpolarizability) indicate that enforcing the exact conditions is not important for these cases. On the other hand, in the time-dependent case, constraining both energy balance and zero net force yields improved results relative to TDHF calculations. We explored the electron dynamics in small sodium clusters driven by cw laser pulses. For each laser pulse we compared calculations from TD constrained xKLI, TD partially constrained xKLI, and TDHF. We found that electron dynamics such as electron ionization and moment of inertia dynamics for the constrained xKLI are most similar to the TDHF results. Also, energy conservation is better by at least one order of magnitude with respect to the unconstrained xKLI. We also discuss the problems that arise in satisfying constraints in the TD case with a non-cw driving force.

Islands of knowledge: science and agriculture in the history of Latin America and the Caribbean.

PubMed

Fernández Prieto, Leida

2013-12-01

This essay explores the participation of Latin America and the Caribbean in the construction and circulation of tropical agricultural science during the nineteenth century and the first half of the twentieth century. It uses the term "islands of knowledge" to underscore the idea that each producing region across the global tropics, including Latin America and the Caribbean, was instrumental in the creation, adoption, and application of scientific procedures. At the same time, it emphasizes the value of interchange and interconnection between these regions, as well as the many and heterogeneous local areas, for analyzing what it calls "global archipelago agricultural scientific knowledge." This focus challenges the traditional center/periphery hierarchy and opens it to a wider vision of science and practice in agriculture. This essay shows how writing in related areas of research--specifically, commodity histories, biological exchange studies, and knowledge exchange studies--introduces approaches and case studies that are useful for the history of tropical agricultural science. In particular, this work provides analytical frameworks for developing studies of exchanges across the Global South.

Complexity and conflicts of interest statements: a case-study of emails exchanged between Coca-Cola and the principal investigators of the International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE).

PubMed

Stuckler, David; Ruskin, Gary; McKee, Martin

2018-02-01

Statements on conflicts of interest provide important information for readers of scientific papers. There is now compelling evidence from several fields that papers reporting funding from organizations that have an interest in the results often generate different findings from those that do not report such funding. We describe the findings of an analysis of correspondence between representatives of a major soft drinks company and scientists researching childhood obesity. Although the studies report no influence by the funder, the correspondence describes detailed exchanges on the study design, presentation of results and acknowledgement of funding. This raises important questions about the meaning of standard statements on conflicts of interest.

Technical Complications during Veno-Venous Extracorporeal Membrane Oxygenation and Their Relevance Predicting a System-Exchange – Retrospective Analysis of 265 Cases

PubMed Central

Lubnow, Matthias; Philipp, Alois; Foltan, Maik; Bull Enger, Tone; Lunz, Dirk; Bein, Thomas; Haneya, Assad; Schmid, Christof; Riegger, Günter; Müller, Thomas; Lehle, Karla

2014-01-01

Objectives Technical complications are a known hazard in veno-venous extracorporeal membrane oxygenation (vvECMO). Identifying these complications and predictive factors indicating a developing system-exchange was the goal of the study. Methods Retrospective study on prospectively collected data of technical complications including 265 adult patients (Regensburg ECMO Registry, 2009-2013) with acute respiratory failure treated with vvECMO. Alterations in blood flow resistance, gas transfer capability, hemolysis, coagulation and hemostasis parameters were evaluated in conjunction with a system-exchange in all patients with at least one exchange (n = 83). Results Values presented as median (interquartile range). Patient age was 50(36–60) years, the SOFA score 11(8–14.3) and the Murray lung injury Score 3.33(3.3–3.7). Cumulative ECMO support time 3411 days, 9(6–15) days per patient. Mechanical failure of the blood pump (n = 5), MO (n = 2) or cannula (n = 1) accounted for 10% of the exchanges. Acute clot formation within the pump head (visible clots, increase in plasma free hemoglobin (frHb), serum lactate dehydrogenase (LDH), n = 13) and MO (increase in pressure drop across the MO, n = 16) required an urgent system-exchange, of which nearly 50% could be foreseen by measuring the parameters mentioned below. Reasons for an elective system-exchange were worsening of gas transfer capability (n = 10) and device-related coagulation disorders (n = 32), either local fibrinolysis in the MO due to clot formation (increased D-dimers [DD]), decreased platelet count; n = 24), or device-induced hyperfibrinolysis (increased DD, decreased fibrinogen [FG], decreased platelet count, diffuse bleeding tendency; n = 8), which could be reversed after system-exchange. Four MOs were exchanged due to suspicion of infection. Conclusions The majority of ECMO system-exchanges could be predicted by regular inspection of the complete ECMO circuit, evaluation of gas exchange, pressure drop across the MO and laboratory parameters (DD, FG, platelets, LDH, frHb). These parameters should be monitored in the daily routine to reduce the risk of unexpected ECMO failure. PMID:25464516

Quantitative description of proton exchange processes between water and endogenous and exogenous agents for WEX, CEST, and APT experiments.

PubMed

Zhou, Jinyuan; Wilson, David A; Sun, Phillip Zhe; Klaus, Judith A; Van Zijl, Peter C M

2004-05-01

The proton exchange processes between water and solutes containing exchangeable protons have recently become of interest for monitoring pH effects, detecting cellular mobile proteins and peptides, and enhancing the detection sensitivity of various low-concentration endogenous and exogenous species. In this work, the analytic expressions for water exchange (WEX) filter spectroscopy, chemical exchange-dependent saturation transfer (CEST), and amide proton transfer (APT) experiments are derived by the use of Bloch equations with exchange terms. The effects of the initial states for the system, the difference between a steady state and a saturation state, and the relative contributions of the forward and backward exchange processes are discussed. The theory, in combination with numerical calculations, provides a useful tool for designing experimental schemes and assessing magnetization transfer (MT) processes between water protons and solvent-exchangeable protons. As an example, the case of endogenous amide proton exchange in the rat brain at 4.7 T is analyzed in detail. Copyright 2004 Wiley-Liss, Inc.

Learning Across Cultures: Intercultural Communication and International Educational Exchange.

ERIC Educational Resources Information Center

Althen, Gary, Ed.; And Others

Aspects of intercultural educational activity, research on learning, and implications for educational interchange, and case studies of the application of ideas from the intercultural communication field to work in international educational interchange are addressed in nine papers. Contents include: "Dynamics of Cross-cultural Adjustment: from…

Classroom Observation Practice in Career Schools: A Multiple Case Study

ERIC Educational Resources Information Center

Withers, Marya G.

2017-01-01

Post-secondary career school educational leaders are charged with formulating sufficient, ongoing, and effective faculty development programming to ensure the delivery of quality education in their unique trade-expert led institutions. Classroom observations, which include substantive feedback exchanges from trained personnel are well documented…

An investigation of Forex market efficiency based on detrended fluctuation analysis: A case study for Iran

NASA Astrophysics Data System (ADS)

Abounoori, Esmaiel; Shahrazi, Mahdi; Rasekhi, Saeed

2012-06-01

The efficient market hypothesis (EMH) states that asset prices fully reflect all available information. As a result, speculators cannot predict the future behavior of asset prices and earn excess profits at least after adjusting for risk. Although initial tests of the EMH were performed on stock market data, the EMH was soon applied to other markets including foreign exchange (FX). This study uses the detrended fluctuation analysis (DFA) technique to test 01:12:2005-18:04:2010 Iranian Rial/US Dollar exchange rate time series data to see if it can be explained by the weak form of the EMH. Moreover, to determine changes in the degree of inefficiency over time, the whole period has been divided into four subperiods. The study shows that the Iranian Forex market (the Rial/Dollar case) is weak-form inefficient over the whole period and in each of the subperiods. However, the degree of inefficiency is not constant over time. The findings suggest that profitable risk-adjusted trades could be made using past data.

Cross-Cultural Practices in Art Education: The Art Lunch Project in Turkey

ERIC Educational Resources Information Center

Acer, Dilek

2012-01-01

This article presents a selective review of the literature on cross-cultural art studies, with the aim of identifying their commonalities. The article includes a specific cross-cultural case study, the Art Lunch Project, which the author attended as a representative of Turkey, that aims to exchange practical teaching experiences. The participants…

Charter School Autonomy: The Mismatch between Theory and Practice

ERIC Educational Resources Information Center

Finnigan, Kara S.

2007-01-01

In theory, the charter school concept is based on a trade-off or exchange: greater autonomy for increased accountability. Although charter schools have been operating for more than 10 years, little is known about charter school autonomy in practice. This mixed-methods study used survey and case study data to examine the degree of autonomy of…

Voices from Team-Teaching Classrooms: A Case Study in Junior High Schools in Japan

ERIC Educational Resources Information Center

Fujimoto-Adamson, Naoki

2010-01-01

Team-teaching between a Japanese teacher of language (JTL) and a native-English speaker assistant language teacher (ALT) has been widely implemented in English-language classrooms in Japanese schools for more than 20 years under the Japan Exchange Teaching Program (JET) launched in 1987. This study focuses on the classroom roles and…

Atypical Hemolytic Uremic Syndrome: A Meta-Analysis of Case Reports Confirms the Prevalence of Genetic Mutations and the Shift of Treatment Regimens.

PubMed

Krishnappa, Vinod; Gupta, Mohit; Elrifai, Mohamed; Moftakhar, Bahar; Ensley, Michael J; Vachharajani, Tushar J; Sethi, Sidharth Kumar; Raina, Rupesh

2018-04-01

Atypical hemolytic uremic syndrome (aHUS) is a rare life-threatening thrombotic microangiopathy (TMA) affecting multiple organ systems. Recently, aHUS has been shown to be associated with uncontrolled complement activation due to mutations in the alternative pathway of complement components paving the way for targeted drug therapy. By meta-analysis of case reports, we discuss the impact of new treatment strategies on the resolution time of aHUS symptoms and mortality, and the distribution of genetic mutations. A PubMed/Medline search was conducted for "atypical hemolytic uremic syndrome" case reports published between November 2005 and November 2015. R Version 3.2.2 was used to calculate descriptive statistics and perform univariate analyses. Wilcoxon rank-sum test was used to compare time to symptoms resolution, creatinine and platelet count normalization across the treatment and mutation carrier groups. A total of 259 aHUS patients were reported in 176 articles between 2005 and 2015. In the last 5-year period compared to the precedent, there was an increase in the number of aHUS cases reported (180 vs. 79 cases) and the use of eculizumab also increased (6.3% to 46.1%, P < 0.000), although plasma exchange usage did not change (P = 0.281). CFH antibodies were present in a significantly higher number of patients treated with plasma exchange therapy (19.1%, P = 0.000) while none of the non-plasma exchange therapy group had CFH antibodies. Most common mutation was CFH (50%, 69/139) followed by CFHR1 (35%, 30/85), MCP (22.8%, 23/101) and CFI (16.6%, 17/102). Time to symptoms resolution and serum creatinine or platelet count normalization were not significantly different between eculizumab and non-eculizumab group (P = 0.166, P = 0.361, P = 0.834), and between plasma exchange and non-plasma exchange group (P = 0.150, P = 0.135, P = 0.784). However, both eculizumab and plasma exchange groups had early platelet recovery (22 vs. 30 days and 25.5 vs. 32.5 days), faster creatinine normalization (27 vs. 30.5 days and 27 vs. 37 days) and interestingly, a longer period for symptoms resolution (45.5 vs. 21 days and 30 vs. 18.5 days) compared to non-eculizumab and non-plasma exchange groups. Mortality rate decreased with the use of eculizumab significantly (P = 0.045) compared to non-eculizumab group and there was no change in mortality rate with the use of plasma exchange therapy (P = 0.760) compared to non-plasma exchange group. Plasma exchange continues to be the initial treatment of choice for aHUS. Although significant reduction in the mortality rate was noted with the use of eculizumab, there were no differences in time to resolution of symptoms or serum creatinine or platelet normalization with the use of either eculizumab or plasma therapy. Atypical HUS is acute and life-threatening, so plasma exchange may be initiated before the confirmed diagnosis and in patients positive for CFH antibodies. Eculizumab therapy should be considered once aHUS is confirmed by genetic testing. © 2017 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.

Sister chromatid exchange rate and alkaline comet assay scores in patients with ovarian cancer.

PubMed

Baltaci, Volkan; Kayikçioğlu, Fulya; Alpas, Idil; Zeyneloğlu, Hulusi; Haberal, Ali

2002-01-01

Sister chromatid exchange (SCE) frequencies were studied in patients with different types of ovarian malignancies and in healthy volunteers. The level of DNA damage in patients with ovarian malignancy and control subjects has also been studied by alkaline single cell gel electrophoresis (SCGE), also known as the comet assay. Peripheral blood was collected from 30 patients after histological confirmation of malignancy and 20 healthy female volunteers. The cells were evaluated according to their grade of damage. We found that the sister chromatid exchange frequencies of cancer cases were significantly greater than that of controls (P < 0.001). The frequency of exchange in chromosomal groups A, B, and C, which include chromosomes 1-12, was higher than that of the other chromosomal groups in both groups. Comparison of the results of the alkaline comet assay in patient and control subjects showed a significant difference in the number of damaged cells. The frequency of limited migrated and extensive migrated cells in the women with ovarian malignancies was higher than that of control women (P < 0.001). SCE and SCGE can be used successfully to monitor DNA damage in women with ovarian cancer.

Towards Designing a Secure Exchange Platform for Diabetes Monitoring and Therapy.

PubMed

Weiß, Jan-Patrick; Welzel, Tobias; Hartmann, Bernd J; Hübner, Ursula; Teuteberg, Frank

2018-01-01

Diabetes mellitus is one of the most prominent examples of chronic conditions that requires an active patient self-management and a network of specialists. The aim of this study was to analyze the user and legal requirements and develop a rough technology concept for a secure and patient-centered exchange platform. To this end, 14 experts representing different stakeholders were interviewed and took part in group discussions at three workshops, the pertinent literature and legal texts were analyzed. The user requirements embraced a comprehensive set of use cases and the demand for "one platform for all" which is underlined by the right for data portability according to new regulations. In order to meet these requirements a distributed ledger technology was proposed. We will therefore focus on a patient-centered application that showcases self-management and exchange with health specialists.

Father, Son, Wife, Husband: Philanthropy as Exchange and Balance.

PubMed

Chan, Kwok-Bun

2010-09-01

This essay attempts to use exchange and balance theories to explain philanthropy. For exchange, such theoretical components as attractions or rewards, costs, barriers and alternatives are invoked to make sense of the biography of a Chinese philanthropist in Hong Kong who donated two schools to remember his father and wife. The balance theory was also used, which argues that people do not seek to maximize their pleasure or to minimize their pain, but to balance, advancing one purpose or concern without neglecting the other-to enhance their well-being and to act morally. The essay argues that the case study method is most able to handle complex behaviour and complex lives. It concludes with a plea for more active use of social theory in research on philanthropy as moral and economic behavior embedded in the social contexts of family, marriage and community.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rehman, Nasir, E-mail: nasirzainy1@hotmail.com; Shashiashvili, Malkhaz

The classical Garman-Kohlhagen model for the currency exchange assumes that the domestic and foreign currency risk-free interest rates are constant and the exchange rate follows a log-normal diffusion process.In this paper we consider the general case, when exchange rate evolves according to arbitrary one-dimensional diffusion process with local volatility that is the function of time and the current exchange rate and where the domestic and foreign currency risk-free interest rates may be arbitrary continuous functions of time. First non-trivial problem we encounter in time-dependent case is the continuity in time argument of the value function of the American put optionmore » and the regularity properties of the optimal exercise boundary. We establish these properties based on systematic use of the monotonicity in volatility for the value functions of the American as well as European options with convex payoffs together with the Dynamic Programming Principle and we obtain certain type of comparison result for the value functions and corresponding exercise boundaries for the American puts with different strikes, maturities and volatilities.Starting from the latter fact that the optimal exercise boundary curve is left continuous with right-hand limits we give a mathematically rigorous and transparent derivation of the significant early exercise premium representation for the value function of the American foreign exchange put option as the sum of the European put option value function and the early exercise premium.The proof essentially relies on the particular property of the stochastic integral with respect to arbitrary continuous semimartingale over the predictable subsets of its zeros. We derive from the latter the nonlinear integral equation for the optimal exercise boundary which can be studied by numerical methods.« less

An Exactly Soluble Model for Hopping Particles Moving with Correlations Between States due to Exchange Sites

NASA Astrophysics Data System (ADS)

Zhao, Xian-Geng; Jia, Sue-Tang

1992-09-01

The motion of hopping particles on an infinite chain is investigated. The model is characterized by the correlations between states due to exchange sites. The analytic solutions for this system are discussed in general case. For some special cases, exact results are obtained with the help of explicit calculations of propagators and mean square displacement deviation. Both probability propagators for the creation and annihilation of two particles or for the deformation and formation of Frenkel excitons are indicated.

Analysis of complex-type chromosome exchanges in astronauts' lymphocytes after space flight as a biomarker of high-LET exposure

NASA Technical Reports Server (NTRS)

George, Kerry; Wu, Honglu; Willingham, Veronica; Cucinotta, Francis A.

2002-01-01

High-LET radiation is more efficient in producing complex-type chromosome exchanges than sparsely ionizing radiation, and this can potentially be used as a biomarker of radiation quality. To investigate if complex chromosome exchanges are induced by the high-LET component of space radiation exposure, damage was assessed in astronauts' blood lymphocytes before and after long duration missions of 3-4 months. The frequency of simple translocations increased significantly for most of the crewmembers studied. However, there were few complex exchanges detected and only one crewmember had a significant increase after flight. It has been suggested that the yield of complex chromosome damage could be underestimated when analyzing metaphase cells collected at one time point after irradiation, and analysis of chemically-induced PCC may be more accurate since problems with complicated cell-cycle delays are avoided. However, in this case the yields of chromosome damage were similar for metaphase and PCC analysis of astronauts' lymphocytes. It appears that the use of complex-type exchanges as biomarker of radiation quality in vivo after low-dose chronic exposure in mixed radiation fields is hampered by statistical uncertainties.

Characterizing the Networks of Digital Information that Support Collaborative Adaptive Forest Management in Sierra Nevada Forests

NASA Astrophysics Data System (ADS)

Lei, Shufei; Iles, Alastair; Kelly, Maggi

2015-07-01

Some of the factors that can contribute to the success of collaborative adaptive management—such as social learning, open communication, and trust—are built upon a foundation of the open exchange of information about science and management between participants and the public. Despite the importance of information transparency, the use and flow of information in collaborative adaptive management has not been characterized in detail in the literature, and currently there exist opportunities to develop strategies for increasing the exchange of information, as well as to track information flow in such contexts. As digital information channels and networks have been increased over the last decade, powerful new information monitoring tools have also been evolved allowing for the complete characterization of information products through their production, transport, use, and monitoring. This study uses these tools to investigate the use of various science and management information products in a case study—the Sierra Nevada Adaptive Management Project—using a mixed method (citation analysis, web analytics, and content analysis) research approach borrowed from the information processing and management field. The results from our case study show that information technologies greatly facilitate the flow and use of digital information, leading to multiparty collaborations such as knowledge transfer and public participation in science research. We conclude with recommendations for expanding information exchange in collaborative adaptive management by taking advantage of available information technologies and networks.

Methods for characterizing convective cryoprobe heat transfer in ultrasound gel phantoms.

PubMed

Etheridge, Michael L; Choi, Jeunghwan; Ramadhyani, Satish; Bischof, John C

2013-02-01

While cryosurgery has proven capable in treating of a variety of conditions, it has met with some resistance among physicians, in part due to shortcomings in the ability to predict treatment outcomes. Here we attempt to address several key issues related to predictive modeling by demonstrating methods for accurately characterizing heat transfer from cryoprobes, report temperature dependent thermal properties for ultrasound gel (a convenient tissue phantom) down to cryogenic temperatures, and demonstrate the ability of convective exchange heat transfer boundary conditions to accurately describe freezing in the case of single and multiple interacting cryoprobe(s). Temperature dependent changes in the specific heat and thermal conductivity for ultrasound gel are reported down to -150 °C for the first time here and these data were used to accurately describe freezing in ultrasound gel in subsequent modeling. Freezing around a single and two interacting cryoprobe(s) was characterized in the ultrasound gel phantom by mapping the temperature in and around the "iceball" with carefully placed thermocouple arrays. These experimental data were fit with finite-element modeling in COMSOL Multiphysics, which was used to investigate the sensitivity and effectiveness of convective boundary conditions in describing heat transfer from the cryoprobes. Heat transfer at the probe tip was described in terms of a convective coefficient and the cryogen temperature. While model accuracy depended strongly on spatial (i.e., along the exchange surface) variation in the convective coefficient, it was much less sensitive to spatial and transient variations in the cryogen temperature parameter. The optimized fit, convective exchange conditions for the single-probe case also provided close agreement with the experimental data for the case of two interacting cryoprobes, suggesting that this basic characterization and modeling approach can be extended to accurately describe more complicated, multiprobe freezing geometries. Accurately characterizing cryoprobe behavior in phantoms requires detailed knowledge of the freezing medium's properties throughout the range of expected temperatures and an appropriate description of the heat transfer across the probe's exchange surfaces. Here we demonstrate that convective exchange boundary conditions provide an accurate and versatile description of heat transfer from cryoprobes, offering potential advantages over the traditional constant surface heat flux and constant surface temperature descriptions. In addition, although this study was conducted on Joule-Thomson type cryoprobes, the general methodologies should extend to any probe that is based on convective exchange with a cryogenic fluid.

Charge and Exchange

NASA Technical Reports Server (NTRS)

2008-01-01

Even though comets are basically giant dirty snowballs, a few years ago they surprised astronomers by emitting X-radiation. These X-rays are not produced by multi-million degree gas (as is often the case) but rather by a process called 'charge exchange'. In this process, ionized atoms (which have lost one or more electrons) which are carried within the solar wind collide with neutral atoms in the comet's coma. The solar wind ion can collide with and capture an electron from the neutral comet atom, and in doing so some of the energy of the collision is observed in the form of X-rays. This produces a glow of X-rays on the sunward side of the comet's atmosphere. Charge exchange can occur in a variety of astrophysical settings, and cometary charge exchange provides astronomers a means to study this process up close. The image above is a pretty picture of comet 73P/Schwassmann-Wachmann 3 passing by the Ring Nebula. This image was obtained by the ultraviolet and optical telescope (UVOT) on the Swift gamma-ray burst hunter. The UVOT observations help astronomers to study the structure and chemistry of the comet, while Swift's X-ray Telescope (XRT) simultaneously monitors the charge exchange process. Comet 73P/Schwassmann-Wachmann 3 is currently in the process of breaking up, and the UVOT observations show important details of how this breakup is occurring.

A comprehensive approach to reactive power scheduling in restructured power systems

NASA Astrophysics Data System (ADS)

Shukla, Meera

Financial constraints, regulatory pressure, and need for more economical power transfers have increased the loading of interconnected transmission systems. As a consequence, power systems have been operated close to their maximum power transfer capability limits, making the system more vulnerable to voltage instability events. The problem of voltage collapse characterized by a severe local voltage depression is generally believed to be associated with inadequate VAr support at key buses. The goal of reactive power planning is to maintain a high level of voltage security, through installation of properly sized and located reactive sources and their optimal scheduling. In case of vertically-operated power systems, the reactive requirement of the system is normally satisfied by using all of its reactive sources. But in case of different scenarios of restructured power systems, one may consider a fixed amount of exchange of reactive power through tie lines. Reviewed literature suggests a need for optimal scheduling of reactive power generation for fixed inter area reactive power exchange. The present work proposed a novel approach for reactive power source placement and a novel approach for its scheduling. The VAr source placement technique was based on the property of system connectivity. This is followed by development of optimal reactive power dispatch formulation which facilitated fixed inter area tie line reactive power exchange. This formulation used a Line Flow-Based (LFB) model of power flow analysis. The formulation determined the generation schedule for fixed inter area tie line reactive power exchange. Different operating scenarios were studied to analyze the impact of VAr management approach for vertically operated and restructured power systems. The system loadability, losses, generation and the cost of generation were the performance measures to study the impact of VAr management strategy. The novel approach was demonstrated on IEEE 30 bus system.

Development of an automated experimental setup for the study of ionic-exchange kinetics. Application to the ionic adsorption, equilibrium attainment and dissolution of apatite compounds.

PubMed

Thomann, J M; Gasser, P; Bres, E F; Voegel, J C; Gramain, P

1990-02-01

An ion-selective electrode and microcomputer-based experimental setup for the study of ionic-exchange kinetics between a powdered solid and the solution is described. The equipment is composed of easily available commercial devices and a data acquisition and regularization computer program is presented. The system, especially developed to investigate the ionic adsorption, equilibrium attainment and dissolution of hard mineralized tissues, provides good reliable results by taking into account the volume changes of the reacting solution and the electrode behaviour under different experimental conditions, and by avoiding carbonation of the solution. A second computer program, using the regularized data and the experimental parameters, calculates the quantities of protons consumed and calcium released in the case of equilibrium attainment and dissolution of apatite-like compounds. Finally, typical examples of ion-exchange and dissolution kinetics under constant pH of enamel and synthetic hydroxyapatite are examined.

Extension of analog network coding in wireless information exchange

NASA Astrophysics Data System (ADS)

Chen, Cheng; Huang, Jiaqing

2012-01-01

Ever since the concept of analog network coding(ANC) was put forward by S.Katti, much attention has been focused on how to utilize analog network coding to take advantage of wireless interference, which used to be considered generally harmful, to improve throughput performance. Previously, only the case of two nodes that need to exchange information has been fully discussed while the issue of extending analog network coding to more than three nodes remains undeveloped. In this paper, we propose a practical transmission scheme to extend analog network coding to more than two nodes that need to exchange information among themselves. We start with the case of three nodes that need to exchange information and demonstrate that through utilizing our algorithm, the throughput can achieve 33% and 20% increase compared with that of traditional transmission scheduling and digital network coding, respectively. Then, we generalize the algorithm so that it can fit for occasions with any number of nodes. We also discuss some technical issues and throughput analysis as well as the bit error rate.

Proceedings of the Tri-Service Conference on Corrosion (1987) Held at the Air Force Academy, Colorado on 5-7 May 1987.

DTIC Science & Technology

1987-05-01

j, ’er-,t- -- Case Studies of .- ’." Failures", Proceedinqs, 198O Tri-Ser vice Conference on Corrosion, AFWAL-TR-81- 401(, 1o1. 1, 2’.1-270, (II1). 3...Spiehler, 1981. Gulf of Mexico Study of "v’-. Biofouling on OTEC heat exchanger candidate alloys. Materials Performance 8:16-21. - Little, B. 1980... Case Studies Figure 2 shows the configuration of a straight shank attachment lug without bushing. All lugs, with or without bushing, that were

Struggling to be seen and heard: the underserved and unserved populations.

PubMed

Cheng, Li-Rong Lilly

2014-01-01

The purpose of this paper is to provide some current information on the topic of the underserved and unserved populations including modern-day slaves, stateless/displaced persons, refugees/migrants and indigenous populations. Speech-language pathology education and services for the underserved as well as unserved populations are discussed. Three case studies which demonstrate knowledge transfer and exchange as potential models for future development are presented. These case studies lead to more inquiries, studies, innovations and involvement from individuals and groups who are concerned about the underserved and unserved populations. © 2015 S. Karger AG, Basel.

Redefining Entrepreneurial Learning Paradigms in Developing Countries: A Case Study of Ghana

ERIC Educational Resources Information Center

Owusu-Manu, D.; Afrane, S. K.; Badu, E.; Edwards, D. J.; Brown, M.

2013-01-01

In a rapidly changing world of knowledge exchange, innovation and technological advancements, entrepreneurship continues to fuel economic growth in both developed and developing countries. In the developed world, an increased influx of graduate entrepreneurs sustains economic growth whilst, in contrast, developing countries continue to suffer from…

Music Education for a Nation: Teaching Patriotic Ideas and Ideals in Global Societies

ERIC Educational Resources Information Center

Kallio, Alexis Anja; Partti, Heidi

2013-01-01

In this article the author's examine, through the cases of Finland and Cambodia, expressions of constructive patriotism in educational policy, curriculum documents and music teacher actions and reflections. This study is part of a broader cross-cultural exchange project: "Multicultural Arts University", between researchers and music…

Horizontal gene transfer confers adaptive advantages to phytopathogenic fungi: a case study of catalase-peroxidase in Fusarium verticillioides

USDA-ARS?s Scientific Manuscript database

Horizontal gene transfer (HGT), the exchange and stable integration of genetic material between different evolutionary lineages, is widely observed in fungi. We hypothesize that successful stabilization of HGT elements provides adaptive advantages (e.g., virulence). Catalase/peroxidases (KatGs) are ...

Two-Way Immersion: A Key to Global Awareness.

ERIC Educational Resources Information Center

Howard, Elizabeth R.

2002-01-01

Describes the use of two-way immersion education to provide students with opportunities to understand and appreciate other countries and cultures. The main features of two-way immersion education are bilingual language instruction, cross-cultural understanding, and international exchanges. Includes case study of two-way immersion at the Alicia…

The Quasi-Privatization of a Public Honors College

ERIC Educational Resources Information Center

Berdahl, Robert; Contardo, Jeanne Bayer

2006-01-01

This is a case study of a state institution granted charter status in 1992 in exchange for capping its request for state funds. St. Mary's College of Maryland received widespread freedom from state procedural controls, including procurement, personnel, and some capital development processes. The state, however, retained its oversight of the…

French for Business: A Case Study.

ERIC Educational Resources Information Center

McCullough, Brenda

The paper discusses the development and evolution of the French for Business undergraduate language course at Oregon State University, focusing on: (1) instructor preparation; (2) course structure; (3) course content; (4) the business student as teacher and mentor; (5) cultural exchanges with French-speaking business students; (6) oral and written…

[Thrombotic microangiopathy in pregnancy complicated by acute hemorrhagic-necrotic pancreatitis during early puerperium].

PubMed

Redechová, S; Féderová, L; Hammerová, L; Filkászová, A; Horváthová, D; Redecha, M

2014-06-01

Authors in the article describe a case of a patient with thrombotic thrombocytopenic purpurain 37 weeks gestation complicated by acute severe hemorrhagic-necrotic pancreatitis during the early puerperium. Case report. Ist Department of gynaecology and obstetrics of the Comenius University Bratislava. 33-years-old patient in the 37 weeks gestation was admitted to our department with the signs of HELLP syndrome (hemolysis, elevated liver enzymes, low platelets). Due to the worsening clinical status, we have performed caesarean section. After the transient stabilization of the patient's clinical status, the hemolysis with severe thrombocytopenia reappeared. Based on the clinical signs of abdominal pain and computer tomography, the diagnosis of acute hemorrhagic-necrotic pancreatitis was set. The primary diagnosis was thrombotic thrombocytopenic purpura. Therefore, therapeutic plasma exchange was performed with consequent improvement of the patients clinical state. Normalization of the platelet count was achieved after 4.plasma exchanges. Consequently 5 plasma exchanges were performed. However, one month later, the disease relapsed. Therapeutic plasma exchanges were needed again (4x), with anti CD 20 administration. This therapy had good clinical outcome, without the need for further plasma exchanges. Thrombotic thrombocytopenic purpura is highly lethal disease. Early diagnosis, treatment, and multidisciplinary approach are essential.

Characterization of susceptible chiasma configurations that increase the risk for maternal nondisjunction of chromosome 21.

PubMed

Lamb, N E; Feingold, E; Savage, A; Avramopoulos, D; Freeman, S; Gu, Y; Hallberg, A; Hersey, J; Karadima, G; Pettay, D; Saker, D; Shen, J; Taft, L; Mikkelsen, M; Petersen, M B; Hassold, T; Sherman, S L

1997-09-01

Recent studies of trisomy 21 have shown that altered levels of recombination are associated with maternal non-disjunction occurring at both meiosis I (MI) and meiosis II (MII). To comprehend better the association of recombination with nondisjunction, an understanding of the pattern of meiotic exchange, i.e. the exchange of genetic material at the four-strand stage during prophase, is required. We examined this underlying exchange pattern to determine if specific meiotic configurations are associated with a higher risk of non-disjunction than others. We examined the crossover frequencies of chromosome 21 for three populations: (i) normal female meiotic events; (ii) meiotic events leading to MI non-disjunction; and (iii) those leading to MII non-disjunction. From these crossover frequencies, we estimated the array of meiotic tetrads that produced the observed crossovers. Using this approach, we found that nearly one-half of MI errors were estimated to be achiasmate. The majority of the remaining MI bivalents had exchanges that clustered at the telomere. In contrast, exchanges occurring among MII cases clustered at the pericentromeric region of the chromosome. Unlike the single exchange distributions, double exchanges from the non-disjoined populations seemed to approximate the distribution in the normal population. These data suggest that the location of certain exchanges makes a tetrad susceptible to non-disjunction. Specifically, this susceptibility is associated with the distance between the centromere and closest exchange. This result challenges the widely held concept that events occurring at MII are largely independent of events occurring at MI, and suggests that all non-disjunction events may be initiated during MI and simply resolved at either of the two meiotic stages.

Effectiveness, safety, and cost of partial exchange transfusions in patients with sickle-cell anemia at a sickle cell disease center in sub-Saharan Africa.

PubMed

Boma Muteb, P; Kaluila Mamba, J F J; Muhau Pfutila, P; Bilo, V; Panda Mulefu, J D; Diallo, D A

2017-11-01

The partial exchange transfusions necessary for management of some sickle-cell complications raise the issue of effectiveness in the context of limited resources and inadequate blood safety. This study evaluated the effectiveness, safety, and cost of partial exchange transfusions in 39 patients with sickle-cell anemia in Lubumbashi, looking at the patients' age and gender and the tolerability and direct cost of the transfusions. Excel and SPSS 18 were used for data entry and analysis. Chi2 and Fisher exact tests were used for comparisons. A P-value ≤ 5% was considered statistically significant. The average age of patients was 8.6 ± 6.4 years, and the majority were girls. The most frequent indications were stroke, severe infections, severe vasooclusive crises, and acute chest syndrome. Partial exchange transfusions were effective in improving hemoglobin and hematocrit as well as the percentage of HbS. No acute accident was observed during any partial exchange transfusion; one anti-Kell alloimmunization and 2 cases of iron overload were observed. The annual cost of partial exchange transfusions per patient requiring (and able to afford) regular treatment was US $ 3,345 without iron chelation and more than US $ 5000 with chelation. Partial exchange transfusions are effective and tolerated, but financially inaccessible to the majority of our sickle cell patients. Thus, an assessment is needed of the economic burden of sickle cell complications that require partial exchange transfusions in the context of countries with limited financial resources.

Coordinating unspecified living kidney donation and transplantation across the blood-type barrier in kidney exchange.

PubMed

Glorie, Kristiaan M; de Klerk, Marry; Wagelmans, Albert P M; van de Klundert, Joris J; Zuidema, Willij C; Claas, Frans H J; Weimar, Willem

2013-11-15

This article studies multicenter coordination of unspecified living kidney donation and transplantation across the blood-type barrier in kidney exchange. Important questions are whether such coordination should use domino paired donation or non simultaneous extended altruistic donor chains, what the length of the segments in such chains should be, when they should be terminated, and how much time should be allowed between matching rounds. Furthermore, it is controversial whether the different modalities should be coordinated centrally or locally and independently. Kidney exchange policies are simulated using actual data from the Dutch national kidney exchange program. Sensitivity analysis is performed on the composition of the population, the time unspecified and bridge donors wait before donating to the wait list, the time between matching rounds, and donor renege rates. Central coordination of unspecified donation and transplantation across the blood-type barrier can increase transplants by 10% (PG0.001). Especially highly sensitized and blood type O patients benefit. Sufficient time between matching rounds is essential: three-monthly exchanges result in 31% more transplants than weekly exchanges. Benefits of non simultaneous extended altruistic donor chains are limited in case of low numbers of highly sensitized patients and sufficient unspecified donors. Chains are best terminated when no further segment is part of an optimal exchange within 3 months. There is clear synergy in the central coordination of both unspecified donation and transplantation across the blood-type barrier in kidney exchange. The best configuration of a national program depends on the composition of the patient Y donor population.

Effectiveness of needle/syringe exchange program in Tbilisi.

PubMed

Otiashvili, D; Gambashidze, N; Kapanadze, E; Lomidze, G; Usharidze, D

2006-11-01

IDUs are under the high risk of HIV and other blood born diseases. In Georgia injecting drug use is associated with two third of registered HIV/AIDS cases. Majority of them are also infected with B and C Hepatitis. One of the main components of HIV/AIDS prevention among drug users is considered to be harm reduction programs, among them syringe exchange program. We conducted observational cohort study and performed interviewing participants of syringe exchange program using structured questionnaire. The interviewing was conducted at intake, after 3 months and at the end of the program. During interviewing we used risk assessment questionnaire which we have little adapted (Risk Assessment Battery, Navaline, et al, 1994). The data were statistically analysed using SPPS-11, 5 program. The aim of the study was to assess the efficacy of outreach and needle exchange programs in terms of reduction of HIV risk behavior of injection drug users in Tbilisi. The results of the study show visible reduction in injection risk behavior for clients being in the program for at least three months. There was not seen any significant change in the level of sexual risk behavior, which might suggest the need for targeting this behavior during the further interventions. The results of the study suggest a visible potential benefit to drug users and communities that could be gained through the wide scale implementation of harm reduction programs in Georgia.

Bronchial lumen is the safer route for an airway exchange catheter in double-lumen tube replacement: preventable complication in airway management for thoracic surgery.

PubMed

Wu, Hsiang-Ling; Tai, Ying-Hsuan; Wei, Ling-Fang; Cheng, Hung-Wei; Ho, Chiu-Ming

2017-10-01

There is no current consensus on which lumen an airway exchange catheter (AEC) should be passed through in double-lumen endotracheal tube (DLT) to exchange for a single-lumen endotracheal tube (SLT) after thoracic surgery. We report an unusual case to provide possible solution on this issue. A 71-year-old man with lung adenocarcinoma had an event of a broken exchange catheter used during a DLT replacement with a SLT, after a video-assisted thoracic surgery. The exchange catheter was impinged at the distal tracheal lumen and snapped during manipulation. All three segments of the catheter were retrieved without further airway compromises. Placement of airway tube exchanger into the tracheal lumen of double-lumen tube is a potential contributing factor of the unusual complication. We suggest an exchange catheter be inserted into the bronchial lumen in optimal depth with the adjunct of video laryngoscope, as the safe method for double-lumen tube exchange.

Modifying exchange-spring behavior of CoPt/NiFe bilayer by inserting a Pt or Ru spacer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsu, Jen-Hwa, E-mail: jhhsu@phys.ntu.edu.tw; Tsai, C. L.; Lee, C.-M.

2015-05-07

We herein explore the possibility of obtaining tunable tilted magnetic anisotropy in ordered-CoPt (5 nm)/NiFe(t{sub NiFe}) bilayers through modifying their exchange spring behavior by inserting Pt and Ru-spacers. The tuning process of tilt angle magnetization of NiFe-layer was systematically investigated by varying the Pt or Ru thickness (t{sub Pt} or t{sub Ru}) from 0 to 8 nm at different thicknesses of NiFe (t{sub NiFe} = 1.5, 4.0, and 6.0 nm). Polar magneto-optic Kerr effect (p-MOKE) studies reveal that the bilayers grown in absence of spacers exhibit almost a rectangular hysteresis loop. With the insertion of Pt-spacer, the loop becomes more and more tilted as t{submore » Pt} increases; whereas, in the case of Ru-spacer, the nature of the loops is not simply changing in one direction. The estimated SQR{sub ⊥} (= θ{sub r}/θ{sub s}) values from the p-MOKE loops are found to monotonically decrease with increasing t{sub Pt} when t{sub Pt} ≦ 4 nm. In contrast, in the case of Ru-spacer, an oscillatory behavior for the SQR{sub ⊥} values is apparent when t{sub Ru} ≦ 4 nm. As a result, an oscillatory tilted angle of NiFe spin configuration was obtained in the case of Ru-spacer; while a decoupling effect was prominent for the Pt-spacer. The results of present study reveal that the insertion of Pt and Ru-spacers as an appropriate means for realizing tunable tilted magnetic anisotropy in the CoPt/NiFe exchange springs.« less

Designing a Care Pathway Model - A Case Study of the Outpatient Total Hip Arthroplasty Care Pathway.

PubMed

Oosterholt, Robin I; Simonse, Lianne Wl; Boess, Stella U; Vehmeijer, Stephan Bw

2017-03-09

Although the clinical attributes of total hip arthroplasty (THA) care pathways have been thoroughly researched, a detailed understanding of the equally important organisational attributes is still lacking. The aim of this article is to contribute with a model of the outpatient THA care pathway that depicts how the care team should be organised to enable patient discharge on the day of surgery. The outpatient THA care pathway enables patients to be discharged on the day of surgery, shortening the length of stay and intensifying the provision and organisation of care. We utilise visual care modelling to construct a visual design of the organisation of the care pathway. An embedded case study was conducted of the outpatient THA care pathway at a teaching hospital in the Netherlands. The data were collected using a visual care modelling toolkit in 16 semi-structured interviews. Problems and inefficiencies in the care pathway were identified and addressed in the iterative design process. The results are two visual models of the most critical phases of the outpatient THA care pathway: diagnosis & preparation (1) and mobilisation & discharge (4). The results show the care team composition, critical value exchanges, and sequence that enable patient discharge on the day of surgery. The design addressed existing problems and is an optimisation of the case hospital's pathway. The network of actors consists of the patient (1), radiologist (1), anaesthetist (1), nurse specialist (1), pharmacist (1), orthopaedic surgeon (1,4), physiotherapist (1,4), nurse (4), doctor (4) and patient application (1,4). The critical value exchanges include patient preparation (mental and practical), patient education, aligned care team, efficient sequence of value exchanges, early patient mobilisation, flexible availability of the physiotherapist, functional discharge criteria, joint decision making and availability of the care team.

Dissemination of plasmid-encoded AmpC β-lactamases in antimicrobial resistant Salmonella serotypes originating from humans, pigs and the swine environment.

PubMed

Keelara, Shivaramu; Thakur, Siddhartha

2014-09-17

The aim of this study was to characterize and determine the inter-serovar exchange of AmpC β-lactamase conferring plasmids isolated from humans, pigs and the swine environment. Plasmids isolated from a total of 21 antimicrobial resistant (AMR) Salmonella isolates representing human clinical cases (n=6), pigs (n=6) and the swine farm environment (n=9) were characterized by replicon typing and restriction digestion, inter-serovar transferability by conjugation, and presence of AmpC β-lactamase enzyme encoding gene blaCMY-2 by southern hybridization. Based on replicon typing, the majority (17/21, 81%) of the plasmids belonged to the I1-Iγ Inc group and were between 70 and 103kb. The potential for inter-serovar plasmid transfer was further confirmed by the PCR detection of AMR genes on the plasmids isolated from trans-conjugants. Plasmids from Salmonella serovars Anatum, Ouakam, Johannesburg and Typhimurium isolated from the same cohort of pigs and their environment and S. Heidelberg from a single human clinical isolate had identical plasmids based on digestion with multiple restriction enzymes (EcoRI, HindIII and PstI) and southern blotting. We demonstrated likely horizontal inter-serovar exchange of plasmid-encoding AmpC β-lactamases resistance among MDR Salmonella serotypes isolated from pigs, swine farm environment and clinical human cases. This study provides valuable information on the role of the swine farm environment and by extension other livestock farm environments, as a potential reservoir of resistant bacterial strains that potentially transmit resistance determinants to livestock, in this case, swine, humans and possibly other hosts by horizontal exchange of plasmids. Copyright © 2014 Elsevier B.V. All rights reserved.

Acid-induced exchange of the imino proton in G.C pairs.

PubMed Central

Nonin, S; Leroy, J L; Gueron, M

1996-01-01

Acid-induced catalysis of imino proton exchange in G.C pairs of DNA duplexes is surprisingly fast, being nearly as fast as for the isolated nucleoside, despite base-pair dissociation constants in the range of 10(-5) at neutral or basic pH. It is also observed in terminal G.C pairs of duplexes and in base pairs of drug-DNA complexes. We have measured imino proton exchange in deoxyguanosine and in the duplex (ATATAGATCTATAT) as a function of pH. We show that acid-induced exchange can be assigned to proton transfer from N7-protonated guanosine to cytidine in the open state of the pair. This is faster than transfer from neutral guanosine (the process of intrinsic catalysis previously characterized at neutral ph) due to the lower imino proton pK of the protonated form, 7.2 instead of 9.4. Other interpretations are excluded by a study of exchange catalysis by formiate and cytidine as exchange catalysts. The cross-over pH between the regimes of pH-independent and acid-induced exchange rates is more basic in the case of base pairs than in the mononucleoside, suggestive of an increase by one to two decades in the dissociation constant of the base pair upon N7 protonation of G. Acid-induced catalysis is much weaker in A.T base pairs, as expected in view of the low pK for protonation of thymidine. PMID:8604298

Acid-induced exchange of the imino proton in G.C pairs.

PubMed

Nonin, S; Leroy, J L; Gueron, M

1996-02-15

Acid-induced catalysis of imino proton exchange in G.C pairs of DNA duplexes is surprisingly fast, being nearly as fast as for the isolated nucleoside, despite base-pair dissociation constants in the range of 10(-5) at neutral or basic pH. It is also observed in terminal G.C pairs of duplexes and in base pairs of drug-DNA complexes. We have measured imino proton exchange in deoxyguanosine and in the duplex (ATATAGATCTATAT) as a function of pH. We show that acid-induced exchange can be assigned to proton transfer from N7-protonated guanosine to cytidine in the open state of the pair. This is faster than transfer from neutral guanosine (the process of intrinsic catalysis previously characterized at neutral ph) due to the lower imino proton pK of the protonated form, 7.2 instead of 9.4. Other interpretations are excluded by a study of exchange catalysis by formiate and cytidine as exchange catalysts. The cross-over pH between the regimes of pH-independent and acid-induced exchange rates is more basic in the case of base pairs than in the mononucleoside, suggestive of an increase by one to two decades in the dissociation constant of the base pair upon N7 protonation of G. Acid-induced catalysis is much weaker in A.T base pairs, as expected in view of the low pK for protonation of thymidine.

An Isotopic Exchange Kinetic Model to Assess the Speciation of Metal Available Pool in Soil: The Case of Nickel.

PubMed

Zelano, I O; Sivry, Y; Quantin, C; Gélabert, A; Maury, A; Phalyvong, K; Benedetti, M F

2016-12-06

In this study an innovative approach is proposed to predict the relative contribution of each mineral phase to the total metal availability in soils, which, in other words, could be called the available metal fractionation. Through the use of isotopic exchange kinetics (IEK) performed on typical Ni bearing phases (i.e., two types of serpentines, chlorite, smectite, goethite, and hematite) the isotopic exchange and metal-solid interaction processes are connected, considering both the thermodynamic and kinetic aspects. Results of Ni IEK experiments on mineral phases are fitted with a pseudo-first order kinetic model. For each Ni bearing phase, this allows to (i) determine the number and size of exchangeable pools (E Ni(i) ), (ii) assess their corresponding kinetic constants (k (i) ), and (iii) discuss the mechanism of Ni isotopic exchange at mineral surfaces. It is shown that all the phases investigated, with the only exception of hematite, present at least two distinct reactive pools with significantly different k (i) values. Results suggest also that metal involved in outer-sphere complexes would display isotopic exchange between 100 and 1000 times faster than metal involved in inner-sphere complexes, and that the presence of high and low affinity sites may influence the rate of isotopic exchange up to 1 order of magnitude. Moreover, the method developed represents a tool to predict and estimate Ni mobility and availability in natural soil samples on the basis of soil mineral composition, providing information barely obtained with other techniques.

Effect of mobile phone reminder messages on adherence of stent removal or exchange in patients with benign pancreaticobiliary diseases: a prospectively randomized, controlled study.

PubMed

Gu, Yong; Wang, Limei; Zhao, Lina; Liu, Zhiguo; Luo, Hui; Tao, Qin; Zhang, Rongchun; He, Shuixiang; Wang, Xiangping; Huang, Rui; Zhang, Linhui; Pan, Yanglin; Guo, Xuegang

2016-08-26

Plastic and covered metal stents need to be removed or exchanged within appropriate time in case of undesirable complications. However, it is not uncommon that patients do not follow the recommendation for further stent management after Endoscopic Retrograde Cholangiopancreatography (ERCP). The effect of short message service (SMS) intervention monthly on the stent removal/exchange adherence in patients after ERCP is unknown at this time. A prospective, randomized controlled study was conducted. After receiving regular instructions, patients were randomly assigned to receive SMS reminding monthly (SMS group) for stent removal/exchange or not (control group). The primary outcome was stent removal/exchange adherence within appropriate time (4 months for plastic stent or 7 months for covered stent). Multivariate analysis was performed to assess factors associated with stent removal/exchange adherence within appropriate time. Intention-to-treat analysis was used. A total of 48 patients were randomized, 23 to the SMS group and 25 to the control. Adherence to stent removal/exchange was reported in 78.2 % (18/23) of patients receiving the SMS intervention compared with 40 % (10/25) in the control group (RR 1.98, 95 % CI 1.16-3.31; p = 0 · 010). Among patients with plastic stent insertion, the median interval time from stent implantation to stent removal/exchange were 90 days in the SMS group and 136 days in the control respectively (HR 0.36, 95 % CI 0.16-0.84, p = 0.018). No difference was found between the two groups regarding late-stage stent-related complications. The rate of recurrent abdominal pain tended to be lower in SMS group without significant difference (8.7 vs 28 %, p = 0.144). Multivariate logistic regression analyses revealed that SMS reminding was the only factor associated with adherence of stent removal/exchange (OR 6.73, 95 % CI 1.64-27.54, p = 0.008). This first effectiveness trial demonstrated that SMS reminding monthly could significantly increase the patient adherence to stent removal/exchange after ERCP. The study was respectively registered on July 10 in 2016 at ClinicalTrials.gov ( NCT02831127 ).

The Life Science Exchange: a case study of a sectoral and sub-sectoral knowledge exchange programme.

PubMed

Perkins, Brian Lee; Garlick, Rob; Wren, Jodie; Smart, Jon; Kennedy, Julie; Stephens, Phil; Tudor, Gwyn; Bisson, Jonathan; Ford, David V

2016-04-27

Local and national governments have implemented sector-specific policies to support economic development through innovation, entrepreneurship and knowledge exchange. Supported by the Welsh Government through the European Regional Development Fund, The Life Science Exchange® project was created with the aim to increase interaction between stakeholders, to develop more effective knowledge exchange mechanisms, and to stimulate the formation and maintenance of long-term collaborative relationships within the Welsh life sciences ecosystem. The Life Science Exchange allowed participants to interact with other stakeholder communities (clinical, academic, business, governmental), exchange perspectives and discover new opportunities. Six sub-sector focus groups comprising over 200 senior stakeholders from academia, industry, the Welsh Government and National Health Service were established. Over 18 months, each focus group provided input to inform healthcare innovation policy and knowledge mapping exercises of their respective sub-sectors. Collaborative projects identified during the focus groups and stakeholder engagement were further developed through sandpit events and bespoke support. Each sub-sector focus group produced a report outlining the significant strengths and opportunities in their respective areas of focus, made recommendations to overcome any 'system failures', and identified the stakeholder groups which needed to take action. A second outcome was a stakeholder-driven knowledge mapping exercise for each area of focus. Finally, the sandpit events and bespoke support resulted in participants generating more than £1.66 million in grant funding and inward investment. This article outlines four separate outcomes from the Life Science Exchange programme. The Life Science Exchange process has resulted in a multitude of collaborations, projects, inward investment opportunities and special interest group formations, in addition to securing over ten times its own costs in funding for Wales. The Life Science Exchange model is a simple and straightforward mechanism for a regional or national government to adapt and implement in order to improve innovation, skills, networks and knowledge exchange.

International Economic Diplomacy: A Guide to the Global Economy: The Issues, Institutions, and Influences.

ERIC Educational Resources Information Center

United Nations Association of the United States of America, New York, NY.

This guide is designed to help teachers to prepare students for the rapidly arriving new world order through study of market economics and the global economy. The central section of the guide presents 10 case studies that describe a range of international economic concepts: (1) Debt and Oil; (2) Trade and Protection; (3) Foreign Exchange; (4)…

"Now I See How My Students Feel": Expansive Learning in a Language Awareness Workshop

ERIC Educational Resources Information Center

Fajardo, Guadalupe Ruiz; Torres-Guzmán, María E.

2016-01-01

This study looks at a case study research on a language awareness workshop in a New York public school with a dual language (Spanish/English) program. A learner-centred lesson, taught in Spanish, focused on basic personal information exchanges for in-service teachers who taught only in English and who had some limited knowledge of Spanish. The…

Realizing Daisaku Ikeda's Educational Philosophy through Language Learning and Study Abroad: A Critical Instrumental Case Study

ERIC Educational Resources Information Center

Goulah, Jason

2012-01-01

This article focuses in two ways on Daisaku Ikeda (b. 1928) and language and culture education. First, the author excerpts Ikeda's translated and lesser-known Japanese speeches to explicate his view of world language learning and cultural exchange as curricular components of a broader educational philosophy for becoming "fully human." Second, the…

The Study of the Teaching Models and Prospects of Bilingual Teaching in Local Universities of China-- A Case Study of Leshan Normal University, Sichuan

ERIC Educational Resources Information Center

Ye, Zhou

2016-01-01

In present China, bilingual teaching, as an education model, can meet an urgent demand for increasing interdisciplinary talents who have high levels of professional knowledge as well as competent foreign language abilities to deal with the ever-increasing global social, economic, scientific and technological exchanges, and international…

Exploring the Critical Dialogical Process: Psychological and Physical Spaces Creating Conditions Conducive to Multi-System Collective Action in Higher Education

ERIC Educational Resources Information Center

Pittman-Adkins, Pamela

2015-01-01

Purpose: The purpose of this study is to explore physical and psychological elements conducive to engaging educators from K-12 and higher education in meaningful exchanges that lead to collective action. Research Design: Through a qualitative case study of two higher education sites focused on advancing academically-based service learning…

Creating a data exchange strategy for radiotherapy research: towards federated databases and anonymised public datasets.

PubMed

Skripcak, Tomas; Belka, Claus; Bosch, Walter; Brink, Carsten; Brunner, Thomas; Budach, Volker; Büttner, Daniel; Debus, Jürgen; Dekker, Andre; Grau, Cai; Gulliford, Sarah; Hurkmans, Coen; Just, Uwe; Krause, Mechthild; Lambin, Philippe; Langendijk, Johannes A; Lewensohn, Rolf; Lühr, Armin; Maingon, Philippe; Masucci, Michele; Niyazi, Maximilian; Poortmans, Philip; Simon, Monique; Schmidberger, Heinz; Spezi, Emiliano; Stuschke, Martin; Valentini, Vincenzo; Verheij, Marcel; Whitfield, Gillian; Zackrisson, Björn; Zips, Daniel; Baumann, Michael

2014-12-01

Disconnected cancer research data management and lack of information exchange about planned and ongoing research are complicating the utilisation of internationally collected medical information for improving cancer patient care. Rapidly collecting/pooling data can accelerate translational research in radiation therapy and oncology. The exchange of study data is one of the fundamental principles behind data aggregation and data mining. The possibilities of reproducing the original study results, performing further analyses on existing research data to generate new hypotheses or developing computational models to support medical decisions (e.g. risk/benefit analysis of treatment options) represent just a fraction of the potential benefits of medical data-pooling. Distributed machine learning and knowledge exchange from federated databases can be considered as one beyond other attractive approaches for knowledge generation within "Big Data". Data interoperability between research institutions should be the major concern behind a wider collaboration. Information captured in electronic patient records (EPRs) and study case report forms (eCRFs), linked together with medical imaging and treatment planning data, are deemed to be fundamental elements for large multi-centre studies in the field of radiation therapy and oncology. To fully utilise the captured medical information, the study data have to be more than just an electronic version of a traditional (un-modifiable) paper CRF. Challenges that have to be addressed are data interoperability, utilisation of standards, data quality and privacy concerns, data ownership, rights to publish, data pooling architecture and storage. This paper discusses a framework for conceptual packages of ideas focused on a strategic development for international research data exchange in the field of radiation therapy and oncology. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Creating a data exchange strategy for radiotherapy research: Towards federated databases and anonymised public datasets

PubMed Central

Skripcak, Tomas; Belka, Claus; Bosch, Walter; Brink, Carsten; Brunner, Thomas; Budach, Volker; Büttner, Daniel; Debus, Jürgen; Dekker, Andre; Grau, Cai; Gulliford, Sarah; Hurkmans, Coen; Just, Uwe; Krause, Mechthild; Lambin, Philippe; Langendijk, Johannes A.; Lewensohn, Rolf; Lühr, Armin; Maingon, Philippe; Masucci, Michele; Niyazi, Maximilian; Poortmans, Philip; Simon, Monique; Schmidberger, Heinz; Spezi, Emiliano; Stuschke, Martin; Valentini, Vincenzo; Verheij, Marcel; Whitfield, Gillian; Zackrisson, Björn; Zips, Daniel; Baumann, Michael

2015-01-01

Disconnected cancer research data management and lack of information exchange about planned and ongoing research are complicating the utilisation of internationally collected medical information for improving cancer patient care. Rapidly collecting/pooling data can accelerate translational research in radiation therapy and oncology. The exchange of study data is one of the fundamental principles behind data aggregation and data mining. The possibilities of reproducing the original study results, performing further analyses on existing research data to generate new hypotheses or developing computational models to support medical decisions (e.g. risk/benefit analysis of treatment options) represent just a fraction of the potential benefits of medical data-pooling. Distributed machine learning and knowledge exchange from federated databases can be considered as one beyond other attractive approaches for knowledge generation within “Big Data”. Data interoperability between research institutions should be the major concern behind a wider collaboration. Information captured in electronic patient records (EPRs) and study case report forms (eCRFs), linked together with medical imaging and treatment planning data, are deemed to be fundamental elements for large multi-centre studies in the field of radiation therapy and oncology. To fully utilise the captured medical information, the study data have to be more than just an electronic version of a traditional (un-modifiable) paper CRF. Challenges that have to be addressed are data interoperability, utilisation of standards, data quality and privacy concerns, data ownership, rights to publish, data pooling architecture and storage. This paper discusses a framework for conceptual packages of ideas focused on a strategic development for international research data exchange in the field of radiation therapy and oncology. PMID:25458128

Phase Space Exchange in Thick Wedge Absorbers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neuffer, David

The problem of phase space exchange in wedge absorbers with ionization cooling is discussed. The wedge absorber exchanges transverse and longitudinal phase space by introducing a position-dependent energy loss. In this paper we note that the wedges used with ionization cooling are relatively thick, so that single wedges cause relatively large changes in beam phase space. Calculation methods adapted to such “thick wedge” cases are presented, and beam phase-space transformations through such wedges are discussed.

Significance of independent radon entry rate and air exchange rate assessment for the purpose of radon mitigation effectiveness proper evaluation: case studies.

PubMed

Froňka, A; Jílek, K; Moučka, L; Brabec, M

2011-05-01

Two new single-family houses identified as insufficient with regard to existing radon barrier efficiency, have been selected for further examination. A complex set of radon diagnosis procedures has been applied in order to localise and quantify radon entry pathways into the indoor environment. Independent assessment of radon entry rate and air exchange rate has been carried out using the continuous indoor radon measurement and a specific tracer gas application. Simultaneous assessment of these key determining factors has turned out to be absolutely crucial in the context of major cause identification of elevated indoor radon concentration.

Kinetics of surfactant-mediated epitaxy of III-V semiconductors

NASA Astrophysics Data System (ADS)

Grandjean, N.; Massies, J.

1996-05-01

Surfactant-mediated epitaxy (SME) of III-V semiconductors is studied in the case of the GaAs(001) growth using Te as surfactant. To account for the strong surface segregation of Te, a phenomenological exchange mechanism is used. This process explains the reduction of the surface diffusion length evidenced by scanning tunneling microscopy (STM). However, this kinetics effect is observed only for restricted growth conditions: the As surface coverage should be sufficient to allow the exchange process. STM results as well as Monte Carlo simulations clearly show that the group-V element surface coverage plays a key role in the kinetics of SME of III-V semiconductors.

Calculation of Distribution Dynamics of Inhomogeneous Temperature Field in Range of Fuel Elements by Using FreeFem++

NASA Astrophysics Data System (ADS)

Amosova, E. V.; Shishkin, A. V.

2017-11-01

This article introduces the result of studying the heat exchange in the fuel element of the nuclear reactor fuel magazine. Fuel assemblies are completed as a bundle of cylindrical fuel elements located at the tops of a regular triangle. Uneven distribution of fuel rods in a nuclear reactor’s core forms the inhomogeneity of temperature fields. This article describes the developed method for heat exchange calculation with the account for impact of an inhomogeneous temperature field on the thermal-physical properties of materials and unsteady effects. The acquired calculation results are used for evaluating the tolerable temperature levels in protective case materials.

Sediment exchange to mitigate pollutant exposure in urban soil.

PubMed

Walsh, Daniel; Glass, Katherine; Morris, Samantha; Zhang, Horace; McRae, Isabel; Anderson, Noel; Alfieri, Alysha; Egendorf, Sara Perl; Holberton, Shana; Owrang, Shahandeh; Cheng, Zhongqi

2018-05-15

Urban soil is an ongoing source for lead (Pb) and other pollutant exposure. Sources of clean soil that are locally-available, abundant and inexpensive are needed to place a protective cover layer over degraded urban soil to eliminate direct and indirect pollutant exposures. This study evaluates a novel sediment exchange program recently established in New York City (NYC Clean Soil Bank, CSB) and found that direct exchange of surplus sediment extracted from urban construction projects satisfies these criteria. The CSB has high total yield with 4.2 × 10 5  t of sediment exchanged in five years. Average annual yield (8.5 × 10 4  t yr -1 ) would be sufficient to place a 15-cm (6-in.) sediment cover layer over 3.2 × 10 5  m 2 (80 acres) of impacted urban soil or 1380 community gardens. In a case study of sediment exchange to mitigate community garden soil contamination, Pb content in sediment ranged from 2 to 5 mg kg -1 . This sediment would reduce surface Pb concentrations more than 98% if it was used to encapsulate soil with Pb content exceeding USEPA residential soil standards (400 mg kg -1 ). The maximum observed sediment Pb content is a factor of 42 and 71 lower than median surface soil and garden soil in NYC, respectively. All costs (transportation, chemical testing, etc.) in the CSB are paid by the donor indicating that urban sediment exchange could be an ultra-low-cost source for urban soil mitigation. Urban-scale sediment exchange has advantages over existing national- or provincial-scale sediment exchanges because it can retain and upcycle local sediment resources to attain their highest and best use (e.g. lowering pollutant exposure), achieve circular urban materials metabolism, improve livability and maximize urban sustainability. Published by Elsevier Ltd.

Father, Son, Wife, Husband: Philanthropy as Exchange and Balance

PubMed Central

2010-01-01

This essay attempts to use exchange and balance theories to explain philanthropy. For exchange, such theoretical components as attractions or rewards, costs, barriers and alternatives are invoked to make sense of the biography of a Chinese philanthropist in Hong Kong who donated two schools to remember his father and wife. The balance theory was also used, which argues that people do not seek to maximize their pleasure or to minimize their pain, but to balance, advancing one purpose or concern without neglecting the other—to enhance their well-being and to act morally. The essay argues that the case study method is most able to handle complex behaviour and complex lives. It concludes with a plea for more active use of social theory in research on philanthropy as moral and economic behavior embedded in the social contexts of family, marriage and community. PMID:20835377

Spectroscopic studies of Fe(III) ion-exchanged ETS-10 and ETAS-10 molecular sieves

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sommerfeld, D.A.; Ellis, W.R. Jr.; Eyring, E.M.

1992-11-26

Two new titanium silicate molecular sieves, designated ETS-10 and ETAS-10, have been ion-exchanged with Fe(III). Both products exhibit prominent EPR signals, at g = 6.0 and 4.3, that are assigned to populations of ferric iron on the surface and in the interior cavities, respectively, of the molecular sieve microcrystals. Corollary XPS measurements on these samples indicate that a substantial fraction of the surface iron is present as Fe(II). Chemical modification procedures have been explored in an effort to produce ion-exchanged materials containing no exterior iron. Acid treatment (pH 1.0) proved to be an effective means of achieving this goal inmore » the case of ETS-10-based materials. ETAS-10-based samples do not retain their crystallinity under these conditions. 35 refs., 4 figs., 2 tabs.« less

Mapping transiently formed and sparsely populated conformations on a complex energy landscape.

PubMed

Wang, Yong; Papaleo, Elena; Lindorff-Larsen, Kresten

2016-08-23

Determining the structures, kinetics, thermodynamics and mechanisms that underlie conformational exchange processes in proteins remains extremely difficult. Only in favourable cases is it possible to provide atomic-level descriptions of sparsely populated and transiently formed alternative conformations. Here we benchmark the ability of enhanced-sampling molecular dynamics simulations to determine the free energy landscape of the L99A cavity mutant of T4 lysozyme. We find that the simulations capture key properties previously measured by NMR relaxation dispersion methods including the structure of a minor conformation, the kinetics and thermodynamics of conformational exchange, and the effect of mutations. We discover a new tunnel that involves the transient exposure towards the solvent of an internal cavity, and show it to be relevant for ligand escape. Together, our results provide a comprehensive view of the structural landscape of a protein, and point forward to studies of conformational exchange in systems that are less characterized experimentally.

Design and evaluation of fluidized bed heat recovery for diesel engine systems

NASA Technical Reports Server (NTRS)

Hamm, J. R.; Newby, R. A.; Vidt, E. J.; Lippert, T. E.

1985-01-01

The potential of utilizing fluidized bed heat exchangers in place of conventional counter-flow heat exchangers for heat recovery from adiabatic diesel engine exhaust gas streams was studied. Fluidized bed heat recovery systems were evaluated in three different heavy duty transport applications: (1) heavy duty diesel truck; (2) diesel locomotives; and (3) diesel marine pushboat. The three applications are characterized by differences in overall power output and annual utilization. For each application, the exhaust gas source is a turbocharged-adiabatic diesel core. Representative subposed exhaust gas heat utilization power cycles were selected for conceptual design efforts including design layouts and performance estimates for the fluidized bed heat recovery heat exchangers. The selected power cycles were: organic rankine with RC-1 working fluid, turbocompound power turbine with steam injection, and stirling engine. Fuel economy improvement predictions are used in conjunction with capital cost estimates and fuel price data to determine payback times for the various cases.

Push and pull models to manage patient consent and licensing of multimedia resources in digital repositories for case-based reasoning.

PubMed

Kononowicz, Andrzej A; Zary, Nabil; Davies, David; Heid, Jörn; Woodham, Luke; Hege, Inga

2011-01-01

Patient consents for distribution of multimedia constitute a significant element of medical case-based repositories in medicine. A technical challenge is posed by the right of patients to withdraw permission to disseminate their images or videos. A technical mechanism for spreading information about changes in multimedia usage licenses is sought. The authors gained their experience by developing and managing a large (>340 cases) repository of virtual patients within the European project eViP. The solution for dissemination of license status should reuse and extend existing metadata standards in medical education. Two methods: PUSH and PULL are described differing in the moment of update and the division of responsibilities between parties in the learning object exchange process. The authors recommend usage of the PUSH scenario because it is better adapted to legal requirements in many countries. It needs to be stressed that the solution is based on mutual trust of the exchange partners and therefore is most appropriate for use in educational alliances and consortia. It is hoped that the proposed models for exchanging consents and licensing information will become a crucial part of the technical frameworks for building case-based repositories.

Enrichment and low-level determination of glyphosate, aminomethylphosphonic acid and glufosinate in drinking water after cleanup by cation exchange resin.

PubMed

Küsters, Markus; Gerhartz, Michael

2010-04-01

For the determination of glyphosate, aminomethylphosphonic acid and glufosinate in drinking water, different procedures of enrichment and cleanup were examined using anion exchange or SPE. In many cases interactions of, e.g. alkaline earth metal ions especially calcium could be observed during enrichment and cleanup resulting in loss of analytes. For that reason, a novel cleanup and enrichment procedure for the determination of these phosphonic acid herbicides has been developed in drinking water using cation-exchange resin. In summary, the cleanup procedure with cation-exchange resin developed in this study avoids interactions as described above and is applicable to calcium-rich drinking water samples. After derivatization with 9-fluorenylmethylchloroformate followed by LC with fluorescence detection, LOD of 12, 14 and 12 ng/L and mean recoveries from real-world drinking water samples of 98+/-9, 100+/-16 and 101+/-11% were obtained for glyphosate, aminomethylphosphonic acid and glufosinate, respectively. The low LODs and the high precision permit the analysis of these phosphonic acid herbicides according to the guidelines of the European Commission.

Enhancing the gate fidelity of silicon-based singlet-triplet qubits under symmetric exchange control using optimized pulse sequences

NASA Astrophysics Data System (ADS)

Zhang, Chengxian; Throckmorton, Robert; Yang, Xu-Chen; Wang, Xin; Barnes, Edwin

We perform Randomized Benchmarking of a family of recently introduced control scheme for singlet-triplet qubits in semiconductor double quantum dots, which is optimized to have substantially shorter gate times. We study their performances under the recently introduced symmetric control scheme of changing the exchange interaction by raising and lowering the barrier between the two dots (barrier control) and compare these results to those under the traditional tilt control method in which the exchange interaction is varied by detuning. It has been suggested that the barrier control method encounters a much smaller charge noise. We found that for the cases where the charge noise is dominant, corresponding to the device made on isotopically enriched silicon, the optimized sequences offer much longer coherence time under barrier control compared to the tilt control method of the strength of the exchange interaction. This work was supported by the Research Grants Council of Hong Kong SAR (No. CityU 21300116) and the National Natural Science Foundation of China (No. 11604277), and by LPS-MPO-CMTC.

New insights into proton surface mobility processes in PEMFC catalysts using isotopic exchange methods.

PubMed

Ferreira-Aparicio, Paloma

2009-09-01

The surface chemistry and the adsorption/desorption/exchange behavior of a proton-exchange membrane fuel cell catalyst are analyzed as a case study for the development of tailor-made support materials of enhanced performance and stability. By using H2, D2, and CO as probe molecules, the relevance of some surface functional groups of the catalyst support on several diffusion processes taking place during the adsorption is shown. Sulfonic groups associated with the vulcanized carbon black surface have been detected by means of spectroscopic techniques (X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy) and by analysis of the desorbed products during temperature-programmed desorption tests by mass spectrometry. Such hydrophilic species have been observed to favor proton surface mobility and exchange with Pt-adsorbed deuterium even in the presence of adsorbed CO. This behavior is relevant both for the proper characterization of these kinds of catalysts using adsorption probes and for the design of new surface-modified carbon supports, enabling alternative proton-transfer pathways throughout the catalytic layers toward the membrane.

Mechanism of nuclear spin initiated para-H2 to ortho-H2 conversion.

PubMed

Buntkowsky, G; Walaszek, B; Adamczyk, A; Xu, Y; Limbach, H-H; Chaudret, B

2006-04-28

In this paper a quantitative explanation for a diamagnetic ortho/para H2 conversion is given. The description is based on the quantum-mechanical density matrix formalism originally developed by Alexander and Binsch for studies of exchange processes in NMR spectra. Only the nuclear spin system is treated quantum-mechanically. Employing the model of a three spin system, the reactions of the hydrogen gas with the catalysts are treated as a phenomenological rate process, described by a rate constant. Numerical calculations reveal that for nearly all possible geometrical arrangements of the three spin system an efficient spin conversion is obtained. Only in the chemically improbable case of a linear group H-X-H no spin conversion is obtained. The efficiency of the spin conversion depends strongly on the lifetime of the H-X-H complex and on the presence of exchange interactions between the two hydrogens. Even moderate exchange couplings cause a quench of the spin conversion. Thus a sufficiently strong binding of the dihydrogen to the S spin is necessary to render the quenching by the exchange interaction ineffective.

Intra-oral ignition of monopolar diathermy during transnasal humidified rapid-insufflation ventilatory exchange (THRIVE).

PubMed

Onwochei, D; El-Boghdadly, K; Oakley, R; Ahmad, I

2017-06-01

We present the case of unanticipated airway ignition during hard palate biopsy. Transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) and monopolar diathermy were utilised for the procedure, during which an arc arose from the diathermy tip to a titanium implant, causing a brief ignition on the monopolar diathermy grip. This case highlights the need for maintained awareness of fire risk when using diathermy in the presence of THRIVE during airway surgery. © 2017 The Association of Anaesthetists of Great Britain and Ireland.

Evolutionary Role of Interspecies Hybridization and Genetic Exchanges in Yeasts

PubMed Central

Dujon, Bernard

2012-01-01

Summary: Forced interspecific hybridization has been used in yeasts for many years to study speciation or to construct artificial strains with novel fermentative and metabolic properties. Recent genome analyses indicate that natural hybrids are also generated spontaneously between yeasts belonging to distinct species, creating lineages with novel phenotypes, varied genetic stability, or altered virulence in the case of pathogens. Large segmental introgressions from evolutionarily distant species are also visible in some yeast genomes, suggesting that interspecific genetic exchanges occur during evolution. The origin of this phenomenon remains unclear, but it is likely based on weak prezygotic barriers, limited Dobzhansky-Muller (DM) incompatibilities, and rapid clonal expansions. Newly formed interspecies hybrids suffer rapid changes in the genetic contribution of each parent, including chromosome loss or aneuploidy, translocations, and loss of heterozygosity, that, except in a few recently studied cases, remain to be characterized more precisely at the genomic level by use of modern technologies. We review here known cases of natural or artificially formed interspecies hybrids between yeasts and discuss their potential importance in terms of genome evolution. Problems of meiotic fertility, ploidy constraint, gene and gene product compatibility, and nucleomitochondrial interactions are discussed and placed in the context of other known mechanisms of yeast genome evolution as a model for eukaryotes. PMID:23204364

MetaPath: An Electronic Knowledge Base for Collating, Exchanging and Analyzing Case Studies of Xenobiotic Metabolism

EPA Science Inventory

A new MetaPath information system was developed through a collaborative effort between the Laboratory of Mathematical Chemistry (Bourgas, Bulgaria), EPA’s Office of Research and Development (NHEERL, MED, Duluth, MN and NERL, ERD, Athens, GA), and EPA’s Office of Chemical Safety a...

Cultural Demands of the Host-Nation: International Student Experience and the Public Diplomacy Consequences

ERIC Educational Resources Information Center

Triana, Benjamin

2015-01-01

Traditional approaches for hosting international students tend to focus on classroom achievement rather than on intercultural exchange and cultural immersion. Such approaches lessen the possibility of successful educational experiences which also hinders public diplomacy. Two case studies are presented that reveal how structural changes at a…

Culturally Based Intervention Development: The Case of Latino Families Dealing with Schizophrenia

ERIC Educational Resources Information Center

Barrio, Concepcion; Yamada, Ann-Marie

2010-01-01

Objectives: This article describes the process of developing a culturally based family intervention for Spanish-speaking Latino families with a relative diagnosed with schizophrenia. Method: Our iterative intervention development process was guided by a cultural exchange framework and based on findings from an ethnographic study. We piloted this…

In and out of Synch: Infant Childcare Teachers' Adaptations to Infants' Developmental Changes

ERIC Educational Resources Information Center

Recchia, Susan L.; Shin, Minsun

2012-01-01

This qualitative multi-case study explored the social exchanges and responsive connections between infants and their infant childcare teachers within a group care context. Infants' naturally occurring behaviours were videotaped purposefully at two separate time points, near the end of their first year and approximately six months later. Findings…

The Dynamics of "Market-Making" in Higher Education

ERIC Educational Resources Information Center

Komljenovic, Janja; Robertson, Susan L.

2016-01-01

This paper examines what to some is a well-worked furrow; the processes and outcomes involved in what is typically referred to as "marketization" in the higher education sector. We do this through a case study of Newton University, where we reveal a rapid proliferation of market exchanges involving the administrative division of the…

Bibliography on Cold Regions Science and Technology, Volume 53, Part 1

DTIC Science & Technology

1999-12-01

Greenland t80/ tain regions: the case study of the Ritigraben tor-Chepyzhenko, V.I., Lautin, L.M., 160 ice core records and North Atlantic foramin - rent...recent planktic foramin - models, Computerized simulation 53-1858 ifera and water mass properties in the western 53-1851 Antarctic Treaty exchange of

The Characteristic Mobile Learning Engagement Strategies of International School Middle-Years Students

ERIC Educational Resources Information Center

Arnold, Bradley A.

2018-01-01

The purpose of this qualitative case study was to develop descriptions of how teenage students remain engaged in learning while using mobile technology. Developments in technology have expanded learning contexts and provided learners with improved capacities to connect with others to exchange, gain, and construct knowledge. Developments in…

Bilateral Learning and Teaching in Chinese-Australian Arts and Architecture

ERIC Educational Resources Information Center

Joubert, Lindy; Whitford, Steven

2006-01-01

A collaborative design-based, cross-cultural exchange between the Chinese School of Architecture, Tsinghua University of Beijing, and the Faculty of Architecture, Building, and Planning at the University of Melbourne is the case study presented in this article. Two design studios were conducted: one in the Master of Urban Design program, and the…

Unalienated Recognition as a Feature of Democratic Schooling

ERIC Educational Resources Information Center

Rheingold, Alison

2012-01-01

The current era of standards and accountability in U.S. public schooling narrows recognition and assessment to an almost exclusive focus on the production of test scores as legitimate markers of student achievement. This climate prevents rather than encourages democratic forms of exchange within and across social worlds. Via a case study of one…

Unlocking the Potential of Urban Communities: Case Studies of Twelve Learning Cities

ERIC Educational Resources Information Center

Valdés-Cotera, Raúl, Ed.; Longworth, Norman, Ed.; Lunardon, Katharina, Ed.; Wang, Mo, Ed.; Jo, Sunok, Ed.; Crowe, Sinéad, Ed.

2015-01-01

UNESCO established the UNESCO Global Network of Learning Cities (GNLC) to encourage the development of learning cities. By providing technical support, capacity development, and a platform where members can share ideas on policies and best practice, this international exchange network helps urban communities create thriving learning cities. The…

Community pharmacy-based point-of-care testing: A case study of pharmacist-physician collaborative working relationships.

PubMed

Bacci, Jennifer L; Klepser, Donald; Tilley, Heather; Smith, Jaclyn K; Klepser, Michael E

2018-01-01

Building collaborative working relationships (CWRs) with physicians or other prescribers is an important step for community pharmacists in establishing a collaborative practice agreement (CPA). This case study describes the individual, context, and exchange factors that drive pharmacist-physician CWR development for community pharmacy-based point-of-care (POC) testing. Two physicians who had entered in a CPA with community pharmacists to provide POC testing were surveyed and interviewed. High scores on the pharmacist-physician collaborative index indicated a high level of collaboration between the physicians and the pharmacist who initiated the relationship. Trust was established through the physicians' personal relationships with the pharmacist or due to the community pharmacy organization's strong reputation. The physicians' individual perceptions of community pharmacy-based POC testing affected their CWRs and willingness to establish a CPA. These findings suggest that exchange characteristics remain significant factors in CWR development. Individual factors may also contribute to physicians' willingness to advance their CWR to include a CPA for POC testing. Copyright © 2017 Elsevier Inc. All rights reserved.

Federal funding for syringe exchange in the US: Explaining a long-term policy failure.

PubMed

Showalter, David

2018-05-01

The United States prohibited federal funding for syringe exchange programs for people who inject drugs nearly continuously from 1988 to 2015, despite growing scientific evidence, diminishing AIDS-related controversy, and tens of thousands of deaths from injection-related AIDS. This study investigates the political and institutional bases of this long-term failure to support lifesaving public policy. This study draws on national, regional, and local media coverage, archival sources, and semi-structured, in-depth interviews with 6 long-time syringe exchange researchers and activists from California. I use case-oriented process tracing methods to explain the persistence and reform of the federal funding ban. Though previous studies focus on the symbolic clash between conservative morality and empirical science, I find that changing demographic and regional inequalities in the effects of the AIDS epidemic and dynamics produced by the federal structure of US government were more important factors in the creation and persistence of the funding ban. The persistence and eventual repeal of the ban on federal funding for syringe exchange was a product of the changing demographic, geographic, and political effects of the AIDS epidemic within the federal structure of US government, rather than a consequence of intractable morality politics. These contextual dynamics continue to shape AIDS and public health policy at all levels of government. Copyright © 2018. Published by Elsevier B.V.

Professional ideologies and the development of syringe exchange: Wales as a case study.

PubMed

Keene, J M; Stimson, G V

1997-12-01

This paper is derived from an evaluative study of HIV prevention programs for drug injectors across Wales. It considers how different professional territories and ideologies, concepts of drug misuse and models of HIV prevention may influence policy development. The research involved monitoring the introduction and development of agency and community based syringe exchange schemes and initiatives taken by community pharmacists. Interviews with staff, managers and administrators, and descriptions of service history, development and delivery inform the discussion. HIV prevention varied in different areas of Wales depending on the particular professional group involved, local ideologies regarding drug use treatment, and the extent to which HIV prevention was seen either as a specialist area of expertise and specific remit of drug workers or a generic health care task. Drug agencies with an abstinence policy rejected syringe exchange; instead, prevention in those areas developed in ad hoc ways as health care workers and pharmacists attempted to develop a community based service. Drug agencies with a pre-existing harm minimisation model easily integrated syringe exchange into their work and played the major part in establishing the service, but there was difficulty in extending it beyond their professional caseloads. As there were disincentives to use treatment agencies, and their catchment areas were limited, these factors influenced effective service provision.

Magnetization reversal mechanism and coercivity enhancement in three-dimensional granular Nd-Fe-B magnets studied by micromagnetic simulations

NASA Astrophysics Data System (ADS)

Lee, Jae-Hyeok; Choe, Jinhyeok; Hwang, Shinwon; Kim, Sang-Koog

2017-08-01

We studied the mechanism of magnetization reversals and coercivity enhancements in three-dimensional (3D) granular Nd-Fe-B permanent magnets using finite-element micromagnetic simulations. The magnetization reversals in the hard magnets consisting of hard-phase grains separated by relatively soft-phase grain boundaries were analyzed with reference to the simulation results for the magnetic field-dependent distributions of the local magnetizations. The saturation magnetization of the grain-boundary phase plays a crucial role in the transition between nucleation- and domain-wall-propagation-controlled reversal processes. The smaller the saturation magnetization of the grain-boundary phase is, the more preferable is the nucleation-controlled process, which results in a larger coercivity. The exchange stiffness of the grain-boundary phase determines the preferred paths of domain-wall propagations, whether inward into grains or along the grain boundaries for relatively small and large exchange stiffness, respectively. However, the exchange stiffness of the grain-boundary phase alone does not significantly contribute to coercivity enhancement in cases where the size of hard-phase grains is much greater than the exchange length. This work paves the way for the design of high-performance hard magnets of large coercivity and maximum-energy-product values.

Balanced Steady-State Free Precession (bSSFP) from an effective field perspective: Application to the detection of chemical exchange (bSSFPX).

PubMed

Zhang, Shu; Liu, Zheng; Grant, Aaron; Keupp, Jochen; Lenkinski, Robert E; Vinogradov, Elena

2017-02-01

Chemical exchange saturation transfer (CEST) is a novel contrast mechanism and it is gaining increasing popularity as many promising applications have been proposed and investigated. Fast and quantitative CEST imaging techniques are further needed in order to increase the applicability of CEST for clinical use as well as to derive quantitative physiological and biological information. Steady-state methods for fast CEST imaging have been reported recently. Here, we observe that an extreme case of these methods is a balanced steady-state free precession (bSSFP) sequence. The bSSFP in itself is sensitive to the exchange processes; hence, no additional saturation or preparation is needed for CEST-like data acquisition. The bSSFP experiment can be regarded as observation during saturation, without separate saturation and acquisition modules as used in standard CEST and similar experiments. One of the differences from standard CEST methods is that the bSSFP spectrum is an XY-spectrum not a Z-spectrum. As the first proof-of-principle step, we have implemented the steady-state bSSFP sequence for chemical exchange detection (bSSFPX) and verified its feasibility in phantom studies. These studies have shown that bSSFPX can achieve exchange-mediated contrast comparable to the standard CEST experiment. Therefore, the bSSFPX method has a potential for fast and quantitative CEST data acquisition. Copyright © 2016 Elsevier Inc. All rights reserved.

Parameterizing atmosphere-land surface exchange for climate models with satellite data: A case study for the Southern Great Plains CART site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, W.

High-resolution satellite data provide detailed, quantitative descriptions of land surface characteristics over large areas so that objective scale linkage becomes feasible. With the aid of satellite data, Sellers et al. and Wood and Lakshmi examined the linearity of processes scaled up from 30 m to 15 km. If the phenomenon is scale invariant, then the aggregated value of a function or flux is equivalent to the function computed from aggregated values of controlling variables. The linear relation may be realistic for limited land areas having no large surface contrasts to cause significant horizontal exchange. However, for areas with sharp surfacemore » contrasts, horizontal exchange and different dynamics in the atmospheric boundary may induce nonlinear interactions, such as at interfaces of land-water, forest-farm land, and irrigated crops-desert steppe. The linear approach, however, represents the simplest scenario, and is useful for developing an effective scheme for incorporating subgrid land surface processes into large-scale models. Our studies focus on coupling satellite data and ground measurements with a satellite-data-driven land surface model to parameterize surface fluxes for large-scale climate models. In this case study, we used surface spectral reflectance data from satellite remote sensing to characterize spatial and temporal changes in vegetation and associated surface parameters in an area of about 350 {times} 400 km covering the southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site of the US Department of Energy`s Atmospheric Radiation Measurement (ARM) Program.« less

Implementation of AAPG exchange format

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keiser, K.; Guerrero, I.

1989-03-01

The American Association of Petroleum Geologists (AAPG) has proposed a format for exchanging geologic and other petroleum data. The AAPG Computer Applications Committee approved the proposal at the March 1988 AAPG annual meeting in Houston, Texas. By adopting this format, data input into application software and data exchange between software packages are greatly simplified. Benefits to both users and suppliers of software are substantial. The AAPG exchange format supports a flexible, generic data structure. This flexibility allows application software to use the standard format for storing internal control data. In some cases, extensions to the standard format, such as separationmore » of header and data files and use of data delimiters, permits the use of AAPG format translator programs on data that were defined and generated before the emergence of the exchange format. Translation software, programmed in C, has been written and contributes to successful implementation of the AAPG exchange format in application software.« less

Relationship between radiation-induced aberrations in individual chromosomes and their DNA content: effects of interaction distance

NASA Technical Reports Server (NTRS)

Wu, H.; Durante, M.; Lucas, J. N.

2001-01-01

PURPOSE: To study the effect of the interaction distance on the frequency of inter- and intrachromosome exchanges in individual chromosomes with respect to their DNA content. Assumptions: Chromosome exchanges are formed by misrejoining of two DNA double-strand breaks (DSB) induced within an interaction distance, d. It is assumed that chromosomes in G(0)/G(1) phase of the cell cycle occupy a spherical domain in a cell nucleus, with no spatial overlap between individual chromosome domains. RESULTS: Formulae are derived for the probability of formation of inter-, as well as intra-, chromosome exchanges relating to the DNA content of the chromosome for a given interaction distance. For interaction distances <1 microm, the relative frequency of interchromosome exchanges predicted by the present model is similar to that by Cigarran et al. (1998) based on the assumption that the probability of interchromosome exchanges is proportional to the "surface area" of the chromosome territory. The "surface area" assumption is shown to be a limiting case of d-->0 in the present model. The present model also predicts that the probability of intrachromosome exchanges occurring in individual chromosomes is proportional to their DNA content with correction terms. CONCLUSION: When the interaction distance is small, the "surface area" distribution for chromosome participation in interchromosome exchanges has been expected. However, the present model shows that for the interaction distance as large as 1 microm, the predicted probability of interchromosome exchange formation is still close to the surface area distribution. Therefore, this distribution does not necessarily rule out the formation of complex chromosomal aberrations by long-range misrejoining of DSB.

Change in Psychotherapy: A Dialogical Analysis Single-Case Study of a Patient with Bulimia Nervosa

PubMed Central

Salvini, Alessandro; Faccio, Elena; Mininni, Giuseppe; Romaioli, Diego; Cipolletta, Sabrina; Castelnuovo, Gianluca

2012-01-01

Starting from the critical review of various motivational frameworks of change that have been applied to the study of eating disorders, the present paper provides an alternative conceptualization of the change in psychotherapy presenting a single-case study. We analyzed six psychotherapeutic conversations with a bulimic patient and found out narratives “for” and “against” change. We read them in terms of tension between dominance and exchange in I-positions, as described by Hermans. These results indicate that the dialogical analysis of clinical discourse may be a useful method to investigate change from the beginning to the end of therapy. PMID:23233845

What do external consultants from private and not-for-profit companies offer healthcare commissioners? A qualitative study of knowledge exchange

PubMed Central

Wye, Lesley; Brangan, Emer; Cameron, Ailsa; Gabbay, John; Klein, Jonathan H; Anthwal, Rachel; Pope, Catherine

2015-01-01

Objectives The use of external consultants from private and not-for-profit providers in the National Health Service (NHS) is intended to improve the quality of commissioning. The aim of this study was to learn about the support offered to healthcare commissioners, how external consultants and their clients work together and the perceived impact on the quality of commissioning. Setting NHS commissioning organisations and private and not-for-profit providers. Design Mixed methods case study of eight cases. Data collection 92 interviews with external consultants (n=36), their clients (n=47) and others (n=9). Observation of 25 training events and meetings. Documentation, for example, meeting minutes and reports. Analysis Constant comparison. Data were coded, summarised and analysed by the research team with a coding framework to facilitate cross-case comparison. Results In the four contracts presented here, external providers offered technical solutions (eg, software tools), outsourcing and expertise including project management, data interpretation and brokering relationships with experts. In assessing perceived impact on quality of commissioning, two contracts had limited value, one had short-term benefits and one provided short and longer term benefits. Contracts with commissioners actively learning, embedding and applying new skills were more valued. Other elements of success were: (1) addressing clearly agreed problems of relevance to managerial and operational staff (2) solutions co-produced at all organisational levels (3) external consultants working directly with clients to interpret data outputs to inform locally contextualised commissioning strategies. Without explicit knowledge exchange strategies, outsourcing commissioning to external providers resulted in the NHS clients becoming dependent. Conclusions NHS commissioning will be disadvantaged if commissioners both fail to learn in the short term from the knowledge of external providers and in the longer term lose local skills. Knowledge exchange mechanisms are a vital component of commissioning and should be embedded in external provider contracts. PMID:25716174

Managing Discourse in Intercultural Business Email Interactions: A Case Study of a British and Italian Business Transaction

ERIC Educational Resources Information Center

Incelli, Ersilia

2013-01-01

This paper investigates native speaker (NS) and non-native speaker (NNS) interaction in the workplace in computer-mediated communication (CMC). Based on empirical data from a 10-month email exchange between a medium-sized British company and a small-sized Italian company, the general aim of this study is to explore the nature of the intercultural…

Intercalation of gaseous thiols and sulfides into Ag+ ion-exchanged aluminum dihydrogen triphosphate.

PubMed

Hayashi, Aki; Saimen, Hiroki; Watanabe, Nobuaki; Kimura, Hitomi; Kobayashi, Ayumi; Nakayama, Hirokazu; Tsuhako, Mitsutomo

2005-08-02

Ag(+) ion-exchanged layered aluminum dihydrogen triphosphate (AlP) with the interlayer distance of 0.85 nm was synthesized by the ion-exchange of proton in triphosphate with Ag(+) ion. The amount of exchanged Ag(+) ion depended on the concentration of AgNO(3) aqueous solution. Ag(+) ion-exchanged AlP adsorbed gaseous thiols and sulfides into the interlayer region. The adsorption amounts of thiols were more than those of sulfides, thiols with one mercapto group > thiol with two mercapto groups > sulfides, and depended on the amount of exchanged Ag(+) ion in the interlayer region. The thiols with one mercapto group were intercalated to expand the interlayer distance of Ag(+) ion-exchanged AlP, whereas there was no expansion in the adsorption of sulfide. In the case of thiol with two mercapto groups, there was observed contraction of the interlayer distance through the bridging with Ag(+) ions of the upper and lower sides of the interlayer region.

[STUDY OF THE IMPACT OF WHEAT GERM CAKE OIL AND FLOUR ON INDICES OF ENERGY EXCHANGE IN STUDENTS AND TEACHERS OF HIGH SCHOOL].

PubMed

Esaulenko, I E; Rodionova, N S; Popov, E S; Melikhova, E P; Khatuaev, R O

2015-01-01

There were obtained data which confirm the increase of efficiency of gas exchange processes in students and teachers of the engineering high school in the daily use of at least 3.5 g of wheat germ oil and 50 g of wheat germ cake flour without the correction of the basic ration. The study of the exhaled gas-air mixture showed in all age groups the gain in the concentration of carbon dioxide and the decline of concentration of oxygen by the 0.20-0.30%. There was established the increase of blood oxygenation level in all subjects. There was demonstrated the relationship between the depth of the alteration of these parameters with age, and regular physical activity in studied cases.

Optimum Energy Extraction from Coherent Vortex Rings Passing Tangentially Over Flexible Plates

NASA Astrophysics Data System (ADS)

Pirnia, Alireza; Browning, Emily A.; Peterson, Sean D.; Erath, Byron D.

2017-11-01

Coherent vortical structures can incite self-sustained oscillations in flexible membranes. This concept has recently gained interest for energy extraction from ambient environments. In this study the special case of a vortex ring passing tangentially over a cantilevered flexible plate is investigated. This problem is governed by the Kirchhoff-Love plate equation, which can be expressed in terms of a non-dimensional mass parameter of the plate, non-dimensional pressure loading induced by the vortex ring, and a Strouhal (St) number which expresses the duration of pressure loading relative to the period of plate oscillation. For a plate with a fixed mass parameter immersed in a fluid environment, the St number specifies the beam dynamics and the energy exchange process. The aim of this study is to identify the St number corresponding to maximum energy exchange between plates and vortex rings. The energy exchange process between the vortex ring and the plate is investigated over a range of 0.3

Wild Chimpanzees Exchange Meat for Sex on a Long-Term Basis

PubMed Central

Gomes, Cristina M.; Boesch, Christophe

2009-01-01

Humans and chimpanzees are unusual among primates in that they frequently perform group hunts of mammalian prey and share meat with conspecifics. Especially interesting are cases in which males give meat to unrelated females. The meat-for-sex hypothesis aims at explaining these cases by proposing that males and females exchange meat for sex, which would result in males increasing their mating success and females increasing their caloric intake without suffering the energetic costs and potential risk of injury related to hunting. Although chimpanzees have been shown to share meat extensively with females, there has not been much direct evidence in this species to support the meat-for-sex hypothesis. Here we show that female wild chimpanzees copulate more frequently with those males who, over a period of 22 months, share meat with them. We excluded other alternative hypotheses to exchanging meat for sex, by statistically controlling for rank of the male, age, rank and gregariousness of the female, association patterns of each male-female dyad and meat begging frequency of each female. Although males were more likely to share meat with estrous than anestrous females given their proportional representation in hunting parties, the relationship between mating success and sharing meat remained significant after excluding from the analysis sharing episodes with estrous females. These results strongly suggest that wild chimpanzees exchange meat for sex, and do so on a long-term basis. Similar studies on humans will determine if the direct nutritional benefits that women receive from hunters in foraging societies could also be driving the relationship between reproductive success and good hunting skills. PMID:19352509

Health information exchange implementation: lessons learned and critical success factors from a case study.

PubMed

Feldman, Sue S; Schooley, Benjamin L; Bhavsar, Grishma P

2014-08-15

Much attention has been given to the proposition that the exchange of health information as an act, and health information exchange (HIE), as an entity, are critical components of a framework for health care change, yet little has been studied to understand the value proposition of implementing HIE with a statewide HIE. Such an organization facilitates the exchange of health information across disparate systems, thus following patients as they move across different care settings and encounters, whether or not they share an organizational affiliation. A sociotechnical systems approach and an interorganizational systems framework were used to examine implementation of a health system electronic medical record (EMR) system onto a statewide HIE, under a cooperative agreement with the Office of the National Coordinator for Health Information Technology, and its collaborating organizations. The objective of the study was to focus on the implementation of a health system onto a statewide HIE; provide insight into the technical, organizational, and governance aspects of a large private health system and the Virginia statewide HIE (organizations with the shared goal of exchanging health information); and to understand the organizational motivations and value propositions apparent during HIE implementation. We used a formative evaluation methodology to investigate the first implementation of a health system onto the statewide HIE. Qualitative methods (direct observation, 36 hours), informal information gathering, semistructured interviews (N=12), and document analysis were used to gather data between August 12, 2012 and June 24, 2013. Derived from sociotechnical concepts, a Blended Value Collaboration Enactment Framework guided the data gathering and analysis to understand organizational stakeholders' perspectives across technical, organizational, and governance dimensions. Several challenges, successes, and lessons learned during the implementation of a health system to the statewide HIE were found. The most significant perceived success was accomplishing the implementation, although many interviewees also underscored the value of a project champion with decision-making power. In terms of lessons learned, social reasons were found to be very significant motivators for early implementation, frequently outweighing economic motivations. It was clear that understanding the guides early in the project would have mitigated some of the challenges that emerged, and early communication with the electronic health record vendor so that they have a solid understanding of the undertaking was critical. An HIE implementations evaluation framework was found to be useful for assessing challenges, motivations, value propositions for participating, and success factors to consider for future implementations. This case study illuminates five critical success factors for implementation of a health system onto a statewide HIE. This study also reveals that organizations have varied motivations and value proposition perceptions for engaging in the exchange of health information, few of which, at the early stages, are economically driven.

Health Information Exchange Implementation: Lessons Learned and Critical Success Factors From a Case Study

PubMed Central

2014-01-01

Background Much attention has been given to the proposition that the exchange of health information as an act, and health information exchange (HIE), as an entity, are critical components of a framework for health care change, yet little has been studied to understand the value proposition of implementing HIE with a statewide HIE. Such an organization facilitates the exchange of health information across disparate systems, thus following patients as they move across different care settings and encounters, whether or not they share an organizational affiliation. A sociotechnical systems approach and an interorganizational systems framework were used to examine implementation of a health system electronic medical record (EMR) system onto a statewide HIE, under a cooperative agreement with the Office of the National Coordinator for Health Information Technology, and its collaborating organizations. Objective The objective of the study was to focus on the implementation of a health system onto a statewide HIE; provide insight into the technical, organizational, and governance aspects of a large private health system and the Virginia statewide HIE (organizations with the shared goal of exchanging health information); and to understand the organizational motivations and value propositions apparent during HIE implementation. Methods We used a formative evaluation methodology to investigate the first implementation of a health system onto the statewide HIE. Qualitative methods (direct observation, 36 hours), informal information gathering, semistructured interviews (N=12), and document analysis were used to gather data between August 12, 2012 and June 24, 2013. Derived from sociotechnical concepts, a Blended Value Collaboration Enactment Framework guided the data gathering and analysis to understand organizational stakeholders’ perspectives across technical, organizational, and governance dimensions. Results Several challenges, successes, and lessons learned during the implementation of a health system to the statewide HIE were found. The most significant perceived success was accomplishing the implementation, although many interviewees also underscored the value of a project champion with decision-making power. In terms of lessons learned, social reasons were found to be very significant motivators for early implementation, frequently outweighing economic motivations. It was clear that understanding the guides early in the project would have mitigated some of the challenges that emerged, and early communication with the electronic health record vendor so that they have a solid understanding of the undertaking was critical. An HIE implementations evaluation framework was found to be useful for assessing challenges, motivations, value propositions for participating, and success factors to consider for future implementations. Conclusions This case study illuminates five critical success factors for implementation of a health system onto a statewide HIE. This study also reveals that organizations have varied motivations and value proposition perceptions for engaging in the exchange of health information, few of which, at the early stages, are economically driven. PMID:25599991

Self-Presentations of Just Social Exchange.

ERIC Educational Resources Information Center

Reis, Harry T.

A self-presentational framework for understanding how people define a just exchange and why behaving justly is important to them is proposed. A case is posited for two self-presentational principles of justice -- that one is responsive to the perceived beliefs of significant others in determining what is just; and that one usually comes to believe…

76 FR 45631 - Self-Regulatory Organizations; Financial Industry Regulatory Authority, Inc.; Notice of Filing...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-29

... Proposed Rule Change 1. Purpose (a) Background In light of well publicized securities frauds that resulted... SECURITIES AND EXCHANGE COMMISSION [Release No. 34-64954; File No. SR-FINRA-2010-036] Self...-Case Referrals July 25, 2011. Pursuant to Section 19(b)(1) of the Securities Exchange Act of 1934...

Briefwechsel uber die Partikel "bis" (An Exchange of Letters about the Particle "bis").

ERIC Educational Resources Information Center

Ludwig, Horst; Holschuh, Albrecht

1990-01-01

A discussion, in the form of an animated letter exchange, argues that, contrary to most current grammatical descriptions, the German particle "bis" should not be viewed as a preposition governing the accusative case. Rather, it is demonstrated that "bis" most often occurs as a proclitic adverb. (16 references) (JTC)

Spatial Analysis of Market Economy Innovations in the Former Soviet Union: The Case of Commodity Exchanges

DTIC Science & Technology

1992-10-06

current cooperative movement in the former Soviet Uni’n can be traced to a law adopted in November, 1986 which permitted family members residing...the labor joined the cooperative movement in 1988. Uzbekistan, the largest of the Central Asian republics, claims only one exchange in Tashkent

Exchange Enhancement of the Electron-Phonon Interaction: The Case of Weakly Doped Two-Dimensional Multivalley Semiconductors

NASA Astrophysics Data System (ADS)

Pamuk, Betül; Zoccante, Paolo; Baima, Jacopo; Mauri, Francesco; Calandra, Matteo

2018-04-01

The effect of the exchange interaction on the vibrational properties and on the electron-phonon coupling were investigated in several recent works. In most of the cases, exchange tends to enhance the electron-phonon interaction, although the motivations for such behaviour are not completely understood. Here we consider the class of weakly doped two-dimensional multivalley semiconductors and we demonstrate that a more global picture emerges. In particular we show that in these systems, at low enough doping, even a moderate electron-electron interaction enhances the response to any perturbation inducing a valley polarization. If the valley polarization is due to the electron-phonon coupling, the electron-electron interaction results in an enhancement of the superconducting critical temperature. We demonstrate the applicability of the theory by performing random phase approximation and first principles calculations in transition metal chloronitrides. We find that exchange is responsible for the enhancement of the superconducting critical temperature in LixZrNCl and that much larger Tcs could be obtained in intercalated HfNCl if the synthesis of cleaner samples could remove the Anderson insulating state competing with superconductivity.

Devise of an exhaust gas heat exchanger for a thermal oil heater in a palm oil refinery plant

NASA Astrophysics Data System (ADS)

Chucherd, Panom; Kittisupakorn, Paisan

2017-08-01

This paper presents the devise of an exhaust gas heat exchanger for waste heat recovery of the exhausted flue gas of palm oil refinery plant. This waste heat can be recovered by installing an economizer to heat the feed water which can save the fuel consumption of the coal fired steam boiler and the outlet temperature of flue gas will be controlled in order to avoid the acid dew point temperature and protect the filter bag. The decrease of energy used leads to the reduction of CO2 emission. Two designed economizer studied in this paper are gas in tube and water in tube. The gas in tube exchanger refers to the shell and tube heat exchanger which the flue gas flows in tube; this designed exchanger is used in the existing unit. The new designed water in tube refers to the shell and tube heat exchanger which the water flows in the tube; this designed exchanger is proposed for new implementation. New economizer has the overall coefficient of heat transfer of 19.03 W/m2.K and the surface heat transfer area of 122 m2 in the optimized case. Experimental results show that it is feasible to install economizer in the exhaust flue gas system between the air preheater and the bag filter, which has slightly disadvantage effect in the system. The system can raise the feed water temperature from 40 to 104°C and flow rate 3.31 m3/h, the outlet temperature of flue gas is maintained about 130 °C.

36 CFR 254.16 - Case closing.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Case closing. 254.16 Section 254.16 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF AGRICULTURE LANDOWNERSHIP ADJUSTMENTS Land Exchanges § 254.16 Case closing. (a) Title transfers. Unless otherwise agreed, and...

A mechanistic investigation on copolymerization of ethylene with polar monomers using a cyclophane-based Pd(II) alpha-diimine catalyst.

PubMed

Popeney, Chris S; Guan, Zhibin

2009-09-02

A detailed mechanistic investigation of the copolymerization of ethylene and methyl acrylate (MA) by a Pd(II) cyclophane-based alpha-diimine catalyst is reported. Our previous observations of unusually high incorporations of acrylates in copolymerization using this catalyst (J. Am. Chem. Soc. 2007, 129, 10062) prompted us to conduct a full mechanistic study on ethylene/MA copolymerization, which indicates a dramatic departure from normal Curtin-Hammett kinetic behavior as observed in copolymerization using the normal Brookhart type of Pd(II) alpha-diimine catalysts. Further investigation reveals that this contrasting behavior originates from the axial blocking effect of the cyclophane ligand hindering olefin substitution and equilibration. In equilibrium studies of ethylene with nitriles, the cyclophane catalyst was found to more strongly favor the linearly binding nitrile ligands as compared to the standard acyclic Pd(II) alpha-diimine catalysts. Ethylene exchange rates in the complexes [(N--N)PdMe(C(2)H(4))](+) (N--N = diimine) were measured by 2D EXSY NMR spectroscopy and found to be over 100 times slower in the cyclophane case. Measurement of the slow equilibration of ethylene, methyl acrylate, and 4-methoxystyrene in cyclophane-based Pd(II) olefin complexes by (1)H NMR and fitting of the obtained kinetic plots allowed for the estimation of exchange rates and equilibrium constants of the olefins. After extrapolation to typical polymerization temperature, DeltaG(double dagger) = 20.6 and 16.4 kcal/mol for ethylene-methyl acrylate exchange in the forward (ethylene displacement by methyl acrylate) and reverse directions, respectively. These values are of similar magnitude to the previously determined migratory insertion barriers of ethylene (DeltaG(double dagger) = 18.9 kcal/mol) and methyl acrylate (DeltaG(double dagger) = 16.3 kcal/mol) under equivalent conditions, but contrast strongly to the rapid olefin exchange seen in the Brookhart acyclic catalyst. The large barrier to olefin exchange hinders olefin pre-equilibrium, decreasing the cyclophane catalyst's ability to preferentially incorporate one monomer (in this case ethylene) over the other, thus giving rise to high comonomer incorporations.

Dynamics of Cross-Shore Thermal Exchange Over Nonuniform Bathymetry

NASA Astrophysics Data System (ADS)

Safaie, A.; Davis, K. A.; Pawlak, G. R.

2016-02-01

The hydrodynamics of cross-shelf circulation on the inner shelf influence coastal ecosystems through the transport of heat, salt, nutrients, and planktonic organisms. While cross-shelf exchange on wide continental shelves has received a fair amount of attention in literature, the mechanisms for cross-shelf exchange on narrow shelves with steep, rough, and highly irregular bathymetry, characteristic of coral reef shorelines, is not well understood. Previous observational studies from reefs at Eilat, Israel and Oahu, Hawaii, have demonstrated the importance of surface heat flux in driving cross-shore transport. While both sites experienced offshore surface flow during daytime warming periods and offshore flow near the bed during nighttime cooling, the phase differences between the surface heat fluxes and thermal responses at the two sites indicate different dynamic flow regimes based on momentum and thermal balances. This study examines the dynamical structure of thermally driven flows using numerical modeling to investigate the hypothesis that thermally driven baroclinic exchange is important to cross-shore circulation for tropical coastlines. We use the open-source Regional Ocean Modeling System (ROMS), a free-surface, three-dimensional circulation model, considering a simple wedge case with uniform bathymetry in the alongshore direction, and heat flux applied uniformly to the surface. We examine different flow regimes using scaling of the momentum and thermal balance equations. We also explore the parameter space for the momentum balance describing cross-shore thermal exchange, and thoroughly characterize the exchange structure by investigating the dominant forcing regimes, the mechanisms responsible for modulating thermal circulation, and the effects of temporal variations in vertical mixing and heating/cooling buoyancy flux. Results are compared against existing data sets to evaluate the ability of the model to represent these flows.

Equilibrium pricing in an order book environment: Case study for a spin model

NASA Astrophysics Data System (ADS)

Meudt, Frederik; Schmitt, Thilo A.; Schäfer, Rudi; Guhr, Thomas

2016-07-01

When modeling stock market dynamics, the price formation is often based on an equilibrium mechanism. In real stock exchanges, however, the price formation is governed by the order book. It is thus interesting to check if the resulting stylized facts of a model with equilibrium pricing change, remain the same or, more generally, are compatible with the order book environment. We tackle this issue in the framework of a case study by embedding the Bornholdt-Kaizoji-Fujiwara spin model into the order book dynamics. To this end, we use a recently developed agent based model that realistically incorporates the order book. We find realistic stylized facts. We conclude for the studied case that equilibrium pricing is not needed and that the corresponding assumption of a ;fundamental; price may be abandoned.

Constraints on supersymmetric dark matter for heavy scalar superpartners

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Peisi; Roglans, Roger A.; Spiegel, Daniel D.

2017-05-01

We study the constraints on neutralino dark matter in minimal low energy supersymmetry models and the case of heavy lepton and quark scalar superpartners. For values of the Higgsino and gaugino mass parameters of the order of the weak scale, direct detection experiments are already putting strong bounds on models in which the dominant interactions between the dark matter candidates and nuclei are governed by Higgs boson exchange processes, particularly for positive values of the Higgsino mass parameter mu. For negative values of mu, there can be destructive interference between the amplitudes associated with the exchange of the standard CP-evenmore » Higgs boson and the exchange of the nonstandard one. This leads to specific regions of parameter space which are consistent with the current experimental constraints and a thermal origin of the observed relic density. In this article, we study the current experimental constraints on these scenarios, as well as the future experimental probes, using a combination of direct and indirect dark matter detection and heavy Higgs and electroweakino searches at hadron colliders« less

Quality management benchmarking: FDA compliance in pharmaceutical industry.

PubMed

Jochem, Roland; Landgraf, Katja

2010-01-01

By analyzing and comparing industry and business best practice, processes can be optimized and become more successful mainly because efficiency and competitiveness increase. This paper aims to focus on some examples. Case studies are used to show knowledge exchange in the pharmaceutical industry. Best practice solutions were identified in two companies using a benchmarking method and five-stage model. Despite large administrations, there is much potential regarding business process organization. This project makes it possible for participants to fully understand their business processes. The benchmarking method gives an opportunity to critically analyze value chains (a string of companies or players working together to satisfy market demands for a special product). Knowledge exchange is interesting for companies that like to be global players. Benchmarking supports information exchange and improves competitive ability between different enterprises. Findings suggest that the five-stage model improves efficiency and effectiveness. Furthermore, the model increases the chances for reaching targets. The method gives security to partners that did not have benchmarking experience. The study identifies new quality management procedures. Process management and especially benchmarking is shown to support pharmaceutical industry improvements.

Implementing health information exchange for public health reporting: a comparison of decision and risk management of three regional health information organizations in New York state

PubMed Central

Phillips, Andrew B; Wilson, Rosalind V; Kaushal, Rainu; Merrill, Jacqueline A

2014-01-01

Health information exchange (HIE) is a significant component of healthcare transformation strategies at both the state and national levels. HIE is expected to improve care coordination, and advance public health, but implementation is massively complex and involves significant risk. In New York, three regional health information organizations (RHIOs) implemented an HIE use case for public health reporting by demonstrating capability to deliver accurate responses to electronic queries via a set of services called the Universal Public Health Node. We investigated process and outcomes of the implementation with a comparative case study. Qualitative analysis was structured around a decision and risk matrix. Although each RHIO had a unique operational model, two common factors influenced risk management and implementation success: leadership capable of agile decision-making and commitment to a strong organizational vision. While all three RHIOs achieved certification for the public health reporting, only one has elected to deploy a production version. PMID:23975626

Implementing health information exchange for public health reporting: a comparison of decision and risk management of three regional health information organizations in New York state.

PubMed

Phillips, Andrew B; Wilson, Rosalind V; Kaushal, Rainu; Merrill, Jacqueline A

2014-02-01

Health information exchange (HIE) is a significant component of healthcare transformation strategies at both the state and national levels. HIE is expected to improve care coordination, and advance public health, but implementation is massively complex and involves significant risk. In New York, three regional health information organizations (RHIOs) implemented an HIE use case for public health reporting by demonstrating capability to deliver accurate responses to electronic queries via a set of services called the Universal Public Health Node. We investigated process and outcomes of the implementation with a comparative case study. Qualitative analysis was structured around a decision and risk matrix. Although each RHIO had a unique operational model, two common factors influenced risk management and implementation success: leadership capable of agile decision-making and commitment to a strong organizational vision. While all three RHIOs achieved certification for the public health reporting, only one has elected to deploy a production version.

A Decomposition Method for Security Constrained Economic Dispatch of a Three-Layer Power System

NASA Astrophysics Data System (ADS)

Yang, Junfeng; Luo, Zhiqiang; Dong, Cheng; Lai, Xiaowen; Wang, Yang

2018-01-01

This paper proposes a new decomposition method for the security-constrained economic dispatch in a three-layer large-scale power system. The decomposition is realized using two main techniques. The first is to use Ward equivalencing-based network reduction to reduce the number of variables and constraints in the high-layer model without sacrificing accuracy. The second is to develop a price response function to exchange signal information between neighboring layers, which significantly improves the information exchange efficiency of each iteration and results in less iterations and less computational time. The case studies based on the duplicated RTS-79 system demonstrate the effectiveness and robustness of the proposed method.

Merging and energy exchange between optical filaments

NASA Astrophysics Data System (ADS)

Georgieva, D. A.; Kovachev, L. M.

2015-10-01

We investigate nonlinear interaction between collinear femtosecond laser pulses with power slightly above the critical for self-focusing Pcr trough the processes of cross-phase modulation (CPM) and degenerate four-photon parametric mixing (FPPM). When there is no initial phase difference between the pulses we observe attraction between pulses due to CPM. The final result is merging between the pulses in a single filament with higher power. By method of moments it is found that the attraction depends on the distance between the pulses and has potential character. In the second case we study energy exchange between filaments. This process is described through FPPM scheme and requests initial phase difference between the waves.

Merging and energy exchange between optical filaments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Georgieva, D. A., E-mail: dgeorgieva@tu-sofia.bg; Kovachev, L. M.

2015-10-28

We investigate nonlinear interaction between collinear femtosecond laser pulses with power slightly above the critical for self-focusing P{sub cr} trough the processes of cross-phase modulation (CPM) and degenerate four-photon parametric mixing (FPPM). When there is no initial phase difference between the pulses we observe attraction between pulses due to CPM. The final result is merging between the pulses in a single filament with higher power. By method of moments it is found that the attraction depends on the distance between the pulses and has potential character. In the second case we study energy exchange between filaments. This process is describedmore » through FPPM scheme and requests initial phase difference between the waves.« less

Collaborative Research Projects in the Technology-Enhanced Language Classroom: Preservice and In-Service Teachers Exchange Knowledge about Technology

ERIC Educational Resources Information Center

Schmid, Euline Cutrim; Hegelheimer, Volker

2014-01-01

This paper presents research findings of a longitudinal empirical case study that investigated an innovative Computer Assisted Language Learning (CALL) professional development program for pre-service English as Foreign Language (EFL) teachers. The conceptualization of the program was based on the assumption that pre-service language teachers…

Using an Outdoor Learning Space to Teach Sustainability and Material Processes in HE Product Design

ERIC Educational Resources Information Center

Firth, Richard; Stoltenberg, Einar; Jennings, Trent

2016-01-01

This "case study" of two jewellery workshops, used outdoor learning spaces to explore both its impact on learning outcomes and to introduce some key principles of sustainable working methodologies and practices. Using the beach as the classroom, academics and students from a Norwegian and Scottish (HE) product design exchange programme…

Moving to Open Educational Resources at Athabasca University: A Case Study

ERIC Educational Resources Information Center

Ives, Cindy; Pringle, Mary Margaret

2013-01-01

Since the birth of the World Wide Web, educators have been exchanging ideas and sharing resources online. They are all aware of the turmoil in higher education created by freely available content, including some hopeful developments charted in this issue. Interest has grown steadily over the past decade in making a university-level education…

Global Education and Its Tensions: Case Studies of Two Schools in Singapore and the United States

ERIC Educational Resources Information Center

Choo, Suzanne S.

2017-01-01

Countering the drive to erect walls between nations and communities, the burden is increasingly on educators to develop in students essential skills and dispositions for a more hospitable future. Global education is essentially aimed at addressing the realities of increasingly networked societies and porous exchanges of knowledge, capital, and…

Examining Negotiation in Peer Group Oral Assessment: What Are the Implications?

ERIC Educational Resources Information Center

Gan, Zhengdong

2008-01-01

This article reports on a case study of negotiation that occurred in peer group oral interactions under assessment conditions. Discourse analysis was used to illustrate how participants negotiated and co-constructed the assessment format itself as well as meaning exchange sequences. Analyses of the data point to the advantage of using peer group…

Community College Journal for Research and Planning, Volume VII, Numbers 1 and 2.

ERIC Educational Resources Information Center

Carter, Edith H., Ed.

1990-01-01

Providing a forum for the exchange of information among members of the National Council for Research and Planning, this refereed journal offers articles on various aspects of community college research, management, and planning. The two issues of volume 7 contain the following articles: (1) "Case Studies of Community College High Risk Students:…

A Case Study of Epistemic Order in Mathematics Classroom Dialogue

ERIC Educational Resources Information Center

Ruthven, Kenneth; Hofmann, Riikka

2016-01-01

We define epistemic order as the way in which the exchange and development of knowledge takes place in the classroom, breaking this down into a system of three components: epistemic initiative relating to who sets the agenda in classroom dialogue, and how; epistemic appraisal relating to who judges contributions to classroom dialogue, and how; and…

Stakeholders’ engagement in promoting sustainable development: Businesses and urban forest carbon

Treesearch

N. C. Poudyal; J. P. Siry; J. M. Bowker

2012-01-01

To better understand how businesses’ motivation and support for green projects varies by their organizational objectives and characteristics, this study investigates a case of urban forestry carbon credits in a broader context of climate change mitigation efforts. Companies and organizations currently participating in the Chicago Climate Exchange (CCX) were surveyed...

Building Bridges of Understanding through Continuing Education and Professional Development of Arabs and Israelis

ERIC Educational Resources Information Center

Noyek, Arnold M.; Skinner, Harvey; Davis, Dave; Clark, Ian; Sriharan, Abi; Chalin, Catherine G.

2005-01-01

In this article, we present an educational approach uniquely linked to humanitarian and peace-building goals in conflicted regions of the world. We examine the Canada International Scientific Exchange Program and its lead program, the Middle East Association for Managing Hearing Loss, as a case study. Under a Canadian umbrella, continuing medical…

Chief Information Officer's Role in Adopting an Interoperable Electronic Health Record System for Medical Data Exchange

ERIC Educational Resources Information Center

Akpabio, Akpabio Enebong Ema

2013-01-01

Despite huge growth in hospital technology systems, there remains a dearth of literature examining health care administrator's perceptions of the efficacy of interoperable EHR systems. A qualitative research methodology was used in this multiple-case study to investigate the application of diffusion of innovations theory and the technology…

Evaluating the Use of a Wiki for Collaborative Learning

ERIC Educational Resources Information Center

Su, Feng; Beaumont, Chris

2010-01-01

A wiki is able to provide a learning environment which is closely aligned with the social-constructivist approach and is more natural than many tools where open collaboration and the exchange of ideas are important. This case study analyses and evaluates essential aspects for the successful deployment of a wiki in a higher education setting using…

Thermal effectiveness of multiple shell and tube pass TEMA E heat exchangers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pignotti, A.; Tamborenea, P.I.

1988-02-01

The thermal effectiveness of a TEMAE shell-and-tube heat exchanger, with one shell pass and an arbitrary number of tube passes, is determined under the usual simplifying assumptions of perfect transverse mixing of the shell fluid, no phase change, and temperature independence of the heat capacity rates and the heat transfer coefficient. A purely algebraic solution is obtained for the effectiveness as a functions of the heat capacity rate ratio and the number of heat transfer units. The case with M shell passes and N tube passes is easily expressed in terms of the single-shell-pass case.

Social organization influences the exchange and species richness of medicinal plants in Amazonian homegardens.

PubMed

2016-03-01

Medicinal plants provide indigenous and peasant communities worldwide with means to meet their healthcare needs. Homegardens often act as medicine cabinets, providing easily accessible medicinal plants for household needs. Social structure and social exchanges have been proposed as factors influencing the species diversity that people maintain in their homegardens. Here, we assess the association between the exchange of medicinal knowledge and plant material and medicinal plant richness in homegardens. Using Tsimane' Amazonian homegardens as a case study, we explore whether social organization shapes exchanges of medicinal plant knowledge and medicinal plant material. We also use network centrality measures to evaluate people's location and performance in medicinal plant knowledge and plant material exchange networks. Our results suggest that social organization, specifically kinship and gender relations, influences medicinal plant exchange patterns significantly. Homegardens total and medicinal plant species richness are related to gardeners' centrality in the networks, whereby people with greater centrality maintain greater plant richness. Thus, together with agroecological conditions, social relations among gardeners and the culturally specific social structure seem to be important determinants of plant richness in homegardens. Understanding which factors pattern general species diversity in tropical homegardens, and medicinal plant diversity in particular, can help policy makers, health providers, and local communities to understand better how to promote and preserve medicinal plants in situ. Biocultural approaches that are also gender sensitive offer a culturally appropriate means to reduce the global and local loss of both biological and cultural diversity.

Nuclear magnetic resonance investigation of erythrocyte membranes in chronic myeloproliferative disorders.

PubMed

Morariu, V V; Petrov, L

1986-07-01

The temperature dependence of the apparent water diffusional exchange through erythrocyte membranes in cases of policitemia vera, chronic granulocytic leukemia and primary myelofibrosis was measured by using a nuclear magnetic resonance method in the presence of Mn2+. The thermal transition shifted to lower temperatures in all cases, regardless of the stage of the disease, suggesting a structural alteration of the membrane. The shift of transition indirectly suggests a lower penetration of the erythrocytes by Mn2+. The water exchange time at 37 degrees C also increased, mainly in the blast crisis; it seems to have a prognostic value of some clinical interest. No simple correlation of the water exchange and the following clinical investigations was observed: the white count, the percentage of promyelocites and myeloblasts, the sedimentation rate of blood, the osmotic fragility of erythrocytes, the total concentration of proteins, albumin and immunoglobulins, respectively, in plasma.

Petrobarter: oil, inequality, and the political imagination in and after the Cold War.

PubMed

Rogers, Douglas

2014-04-01

Petrobarter--the exchange of oil for goods and services without reference to monetary currency--has been a widespread and underappreciated practice among corporations, states, and state agencies over the past half century. Analyzing this practice with reference to anthropological theories of barter adds to our understandings of two significant and intertwined concerns in contemporary social science: (1) the production and reproduction of inequality at various scales, from subnational regions to the international system as a whole, and (2) the generation and fate of mobilizing political imaginaries that challenge the abstracted, universalizing imaginaries so often associated with monetized exchange, especially in capitalist contexts. Barter exchanges featuring oil are, therefore, as analytically significant as the much more commonly studied transactions of oil and money. Ethnographic and historical case studies of petrobarter are drawn from the Perm region of the Russian Urals in the post-Soviet period and the global oil trade in the early Cold War. This view from the perspective of the socialist and postsocialist world, it is argued, provides an instructive counterpoint to the many existing studies of oil and money, both in and beyond anthropology, that are situated in the European-American colonial and postcolonial periphery.

Uncertainties of Gaseous Oxidized Mercury Measurements Using KCl-Coated Denuders, Cation-Exchange Membranes, and Nylon Membranes: Humidity Influences.

PubMed

Huang, Jiaoyan; Gustin, Mae Sexauer

2015-05-19

Quantifying the concentration of gaseous oxidized mercury (GOM) and identifying the chemical compounds in the atmosphere are important for developing accurate local, regional, and global biogeochemical cycles. The major hypothesis driving this work was that relative humidity affects collection of GOM on KCl-coated denuders and nylon membranes, both currently being applied to measure GOM. Using a laboratory manifold system and ambient air, GOM capture efficiency on 3 different collection surfaces, including KCl-coated denuders, nylon membranes, and cation-exchange membranes, was investigated at relative humidity ranging from 25 to 75%. Recovery of permeated HgBr2 on KCl-coated denuders declined by 4-60% during spikes of relative humidity (25 to 75%). When spikes were turned off GOM recoveries returned to 60 ± 19% of permeated levels. In some cases, KCl-coated denuders were gradually passivated over time after additional humidity was applied. In this study, GOM recovery on nylon membranes decreased with high humidity and ozone concentrations. However, additional humidity enhanced GOM recovery on cation-exchange membranes. In addition, reduction and oxidation of elemental mercury during experiments was observed. The findings in this study can help to explain field observations in previous studies.

Challenges in computational evaluation of redox and magnetic properties of Fe-based sulfate cathode materials of Li- and Na-ion batteries

NASA Astrophysics Data System (ADS)

Shishkin, Maxim; Sato, Hirofumi

2017-06-01

Several Fe-based sulfates have been proposed recently as cathode materials characterized by a high average operating voltage (i.e. Li2Fe(SO4)2 and Na2Fe2(SO4)3) or low fabrication temperature (e.g. Na2Fe(SO4)2·2H2O)). In this work, we apply three methods to evaluate the redox potentials and magnetic properties of these materials: (1) local density functional theory (DFT) in Perdew-Burke-Ernzerhof parametrization; (2) rotationally invariant DFT  +  U and (3) DFT  +  U with magnetic exchange, suggested herein. The U parameters used for DFT  +  U calculations have been evaluated by using a linear response method (this applies to DFT  +  U as well as DFT  +  U calculations with a magnetic exchange term). Moreover, we have performed adjustments of U and, for the case of magnetic exchange, J parameters, to find better agreement with experimental measurements of redox and magnetic properties. We find that a self-consistent DFT  +  U/linear response approach yields quite overestimated redox potentials as compared to experiment. On the other hand, we also show that DFT  +  U calculations are not capable of providing a reasonably accurate description of both redox and magnetic properties for the case of Li2Fe(SO4)2, even when adjusted U parameters are employed. As a solution, we demonstrate that a DFT  +  U methodology augmented by a magnetic exchange term potentially provides more precise values for both the redox potentials and the magnetic moments of the Fe ions in the studied materials. Thus our work shows that for a more accurate description of redox and magnetic properties, further extensions of the DFT  +  U method, such as inclusion of the contribution of magnetic exchange, should be considered.

77 FR 16295 - Self-Regulatory Organizations; International Securities Exchange, LLC; Notice of Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-20

... trading day's last sale price was greater than $100) in premium in each of the front two expiration months... options whose underlying stock's previous trading day's last sale price was greater than $100) in premium... employing similar pricing schemes and in some cases, is lower that the fees assessed by other exchanges. For...

75 FR 29375 - Self-Regulatory Organizations; C2 Options Exchange, Incorporated; Notice of Filing of a Proposed...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-25

..., as the case may be. See proposed Article Eleventh of the CBOE Holdings Certificate of Incorporation and proposed Article 10.2 of the CBOE Holdings Bylaws. The term ``Regulated Securities Exchange... Holdings], including, but not limited to CBOE.'' See proposed Article Fifth(a) of the CBOE Holdings...

Patient Protection and Affordable Care Act; program integrity: Exchange, SHOP, and eligibility appeals. Final rule.

PubMed

2013-08-30

This final rule implements provisions of the Patient Protection and Affordable Care Act and the Health Care and Education Reconciliation Act of 2010 (collectively referred to as the Affordable Care Act). Specifically, this final rule outlines Exchange standards with respect to eligibility appeals, agents and brokers, privacy and security, issuer direct enrollment, and the handling of consumer cases. It also sets forth standards with respect to a State's operation of the Exchange and Small Business Health Options Program (SHOP). It generally is finalizing previously proposed policies without change.

Benefit of an operating vehicle preventing peritonitis in peritoneal dialysis patients: a retrospective, case-controlled study.

PubMed

Fang, Pan; Lu, Jia; Liu, Ying-Hong; Deng, Hong-Mei; Zhang, Lei; Zhang, Hong-Qing

2018-06-01

Peritonitis, which is one of the leading complications of peritoneal dialysis (PD) worldwide, severely affected morbidity and mortality of the PD patients. Although many efforts have been made to prevent PD-related peritonitis, it seems impossible to prevent it completely. Many causes have been reported to lead to peritonitis, and contamination during bag exchange is one of the important risk factors for peritonitis. Here, we introduce an operating vehicle, which we invented to provide a sterile and safe space for bag exchange. A single-center, retrospective, case-control study was undertaken to determine whether this operating vehicle has a protective role in preventing peritonitis. In total, 462 continuous ambulatory peritoneal dialysis patients were included in this study from October 2014 to March 2017. According to their personal will, these patients chose to use operating vehicle or traditional method during their bag exchange. The demographic, clinical and laboratory data of these patients in the two groups were collected, analyzed and compared. Of 462 patients with home dialysis, operating vehicle group consisted of 61 patients, and control group consisted of 401 patients. In the control group, over 677 patient-years, peritonitis occurred in 69 of 401 patients (17.2%), while in the operating vehicle group, over 60 patient-years, only 4 of 61 patients (6.6%) had episodes of peritonitis. The number of patients suffered from peritonitis was significantly decreased in the operating vehicle group (P = 0.034). Besides, there were a total of 99 episodes of peritonitis, and the rate was 1 episode every 7.2 patient-years in control group and 1 episode every 12 patient-years in the operating vehicle group. There was significant difference between the two groups (0.013). Positive dialysate cultures were obtained in majority of the peritonitis episodes (60.6%). Operating vehicle might help to reduce PD-related peritonitis by preventing contamination during bag exchange. Further studies are still needed to demonstrate the protective role of the operating vehicle in preventing peritonitis.

A Case Study of Using Peer Feedback in Face-to-Face and Distance Learning Classes among Pre-Service Teachers

ERIC Educational Resources Information Center

Vásquez-Colina, María D.; Russo, Marianne Robin; Lieberman, Mary; Morris, John D.

2017-01-01

This study investigated a feedback exchange activity for engaging pre-service teachers and the nature of such feedback in two undergraduate classes, a distance learning (DL) and a face-to-face (F2F) class. The research question asked if the nature of peer feedback was different between F2F and DL class formats. Students' work samples were…

Assessing double counting of carbon emissions between forest land cover change and forest wildfires: a case study in the United States, 1992-2006

Treesearch

Daolan Zheng; Linda S. Heath; Mark J. Ducey; Brad Quayle

2013-01-01

The relative contributions of double counting of carbon emissions between forest-to-nonforest cover change (FNCC) and forest wildfires are an unknown in estimating net forest carbon exchanges at large scales. This study employed land-cover change maps and forest fire data in the four representative states (Arkansas, California, Minnesota, and Washington) of the US for...

The tropopause inversion layer in baroclinic life cycles over the North Atlantic: a pre-WISE case study and climatology

NASA Astrophysics Data System (ADS)

Kaluza, Thorsten; Hoor, Peter; Kunkel, Daniel

2017-04-01

Studies of baroclinic life cycles recently revelead that the tropopause inversion layer (TIL) in the extratropics is significantly strengthened by diabatic processes related to moist tropospheric dynamics as well as by breaking of the baroclinic wave itself. However, these findings summarize the results from idealized model simulations and the contribution from processes related to baroclinic life cycles relative to other processes enhancing the lower stratospheric static stability (stratospheric dynamics, seasonal variation of radiative feedbacks) to the observed TIL at midlatitudes has yet to be assessed. Further the role of the TIL for stratosphere-troposphere exchange (STE) is currently still under debate. In preparation of the up-coming field campaign WISE (Wave driven isentropic exchange) we explore the state and variability of the TIL over the North Atlantic between August and October in analysis model data. We use high resolution operational analysis from the European Center for Medium Range Weather Forecast to study the mesoscale structure of the TIL. The main focus is on case studies of the TIL in real baroclinic life cycles, in particular on small scale enhancements within the baroclinic disturbances and the relation to STE. Moreover, a summary is presented about the quasi climatological state of the tropopause location and sharpness over the North Atlantic over recent years.

Glass corrosion in natural environment

NASA Technical Reports Server (NTRS)

Thorpe, Arthur N.

1989-01-01

A series of studies of the effects of solutes which appear in natural aqueous environments, specifically Mg and Al, under controlled conditions, permit characterization of the retardation of silicate glass leaching in water containing such solutes. In the case of Mg the interaction with the glass appears to consist of exchange with alkali ions present in the glass to a depth of several microns. The effect of Al can be observed at much lower levels, indicating that the mechanism in the case of Al involves irreversible formation of aluminosilicate species at the glass surface.

Effects of PM fouling on the heat exchange effectiveness of wave fin type EGR cooler for diesel engine use

NASA Astrophysics Data System (ADS)

Jang, Sang-Hoon; Hwang, Se-Joon; Park, Sang-Ki; Choi, Kap-Seung; Kim, Hyung-Man

2012-06-01

Developing an effective method of reducing nitrogen oxide emissions is an important goal in diesel engine research. The use of cooled exhaust gas recirculation has been considered one of the most effective techniques of reducing nitrogen oxide. However, since the combustion characteristics in a diesel engine involves high temperature and load, the amount of particulate matter emission tends to increase, and there is a trade-off between the amount of nitrogen oxide and particulate matter emissions. In the present study, engine dynamometer experiments are performed to investigate the effects of particulate matter fouling on the heat exchange characteristics of wave fin type exhaust gas recirculation coolers that have four cases of two wave pitch and three fin pitch lengths. To optimize the fin and wave pitches of the EGR cooler, the exhaust gas temperature, pressure drop and heat exchange effectiveness are compared. The experimental results show that the exhaust gas recirculation cooler with a fin pitch of 3.6 mm and a wave pitch of 8.8 mm exhibits better heat exchange characteristics and smaller particulate matter fouling effect than the other coolers.

Quantifying solute transport processes: are chemically "conservative" tracers electrically conservative?

USGS Publications Warehouse

Singha, Kamini; Li, Li; Day-Lewis, Frederick D.; Regberg, Aaron B.

2012-01-01

The concept of a nonreactive or conservative tracer, commonly invoked in investigations of solute transport, requires additional study in the context of electrical geophysical monitoring. Tracers that are commonly considered conservative may undergo reactive processes, such as ion exchange, thus changing the aqueous composition of the system. As a result, the measured electrical conductivity may reflect not only solute transport but also reactive processes. We have evaluated the impacts of ion exchange reactions, rate-limited mass transfer, and surface conduction on quantifying tracer mass, mean arrival time, and temporal variance in laboratory-scale column experiments. Numerical examples showed that (1) ion exchange can lead to resistivity-estimated tracer mass, velocity, and dispersivity that may be inaccurate; (2) mass transfer leads to an overestimate in the mobile tracer mass and an underestimate in velocity when using electrical methods; and (3) surface conductance does not notably affect estimated moments when high-concentration tracers are used, although this phenomenon may be important at low concentrations or in sediments with high and/or spatially variable cation-exchange capacity. In all cases, colocated groundwater concentration measurements are of high importance for interpreting geophysical data with respect to the controlling transport processes of interest.

Interactions between hyporheic flow produced by stream meanders, bars, and dunes

USGS Publications Warehouse

Stonedahl, Susa H.; Harvey, Judson W.; Packman, Aaron I.

2013-01-01

Stream channel morphology from grain-scale roughness to large meanders drives hyporheic exchange flow. In practice, it is difficult to model hyporheic flow over the wide spectrum of topographic features typically found in rivers. As a result, many studies only characterize isolated exchange processes at a single spatial scale. In this work, we simulated hyporheic flows induced by a range of geomorphic features including meanders, bars and dunes in sand bed streams. Twenty cases were examined with 5 degrees of river meandering. Each meandering river model was run initially without any small topographic features. Models were run again after superimposing only bars and then only dunes, and then run a final time after including all scales of topographic features. This allowed us to investigate the relative importance and interactions between flows induced by different scales of topography. We found that dunes typically contributed more to hyporheic exchange than bars and meanders. Furthermore, our simulations show that the volume of water exchanged and the distributions of hyporheic residence times resulting from various scales of topographic features are close to, but not linearly additive. These findings can potentially be used to develop scaling laws for hyporheic flow that can be widely applied in streams and rivers.

The role of charge-exchange cross-section for pickup protons and neutrals in the inner heliosheath

NASA Astrophysics Data System (ADS)

Chalov, S. V.

2018-06-01

The process of deceleration of the solar wind downstream of the termination shock is studied on the basis of a one-dimensional multi-component model. It is assumed that the solar wind consists of thermal protons, electrons and interstellar pickup protons. The protons interact with interstellar hydrogen atoms by charge-exchange. Two cases are considered. In the first one, the charge-exchange cross-section for thermal protons and hydrogen atoms is the same as for pickup protons and atoms. Under this condition, there is a strong dependence of the solar wind velocity on the downstream temperature of pickup protons. When the proton temperature is close to 10 keV, the change in the velocity with the distance from the termination shock is similar to that measured on the Voyager 1 spacecraft: linear velocity decrease is accompanied by an extended transition region with near-zero velocity. However, with a more careful approach to the choice of the charge-exchange cross-section, the situation changes dramatically. The strong dependence of the solar wind speed on the pickup proton temperature disappears and the transition region in the heliosheath disappears as well, at least at reasonable distances from the TS.

The climatic effects of nuclear war

NASA Technical Reports Server (NTRS)

Turco, R. P.; Toon, O. B.; Ackerman, T. P.; Pollack, J. B.; Sagan, C.

1984-01-01

The effects of various US-USSR nuclear-exchange scenarios on global climate are investigated by means of computer simulations, summarizing the results of Turco et al. (1983) and follow-up studies using 3D global-circulation models. A nuclear-scenario model is used to determine the amounts of dust, smoke, radioactivity, and pyrotoxins generated by a particular type of nuclear exchange (such as a general 5,000-Mt exchange, a 1,000-Mt limited exchange, a 5,000-Mt hard-target counterforce attack, and a 100-Mt attack on cities only): a particle-microphysics model predicts the evolution of the dust and smoke particles; and a radiative-convective climate model estimates the effects of the dust and smoke clouds on the global radiation budget. The findings are presented in graphs, diagrams, and a table. Thick clouds blocking most sunlight over the Northern Hemisphere midlatitudes for weeks or months and producing ground-temperature reductions of 20-40 C, disruption of global circulation patterns, and rapid spread of clouds to the Southern Hemisphere are among the 'nuclear-winter' effects predicted for the 5,000-Mt baseline case. The catastrophic consequences for plant, animal, and human populations are considered, and the revision of superpower nuclear strategies is urged.

Nuclear structure properties of the double-charge-exchange transition amplitudes

NASA Astrophysics Data System (ADS)

Auerbach, N.; Zheng, D. C.

1992-03-01

Nuclear structure aspects of the double-charge-exchange (DCX) reaction on nuclei are studied. Using a variety of DCX-type two-body transition operators, we explore the influence of two-body correlations among valence nucleons on the DCX transition amplitudes to the isobaric analog state and to other nonanalog J π=0+ states. In particular, the question of the spin dependence and of the range of the DCX transition operators is explored and the behavior of the transition amplitudes as a function of the valence nucleon number is studied. It is shown that the two-amplitude DCX formula derived by Auerbach, Gibbs, and Piasetzky for a single j n configuration holds also in some cases when configuration mixing is strong. DCX-type transitions from the Ca and Ni isotopes to the Ti and Zn isotopes and from 56Fe to 56Ni are the subject of this study.

Decreased visual acuity resulting from glistening and sub-surface nano-glistening formation in intraocular lenses: A retrospective analysis of 5 cases

PubMed Central

Matsushima, Hiroyuki; Nagata, Mayumi; Katsuki, Yoko; Ota, Ichiro; Miyake, Kensaku; Beiko, George H.H.; Grzybowski, Andrzej

2015-01-01

Background To report on five patients with decreased visual acuity due to glistening and severe sub-surface nano-glistening (SSNG) formation within their intraocular lenses (IOLs). Design Case reports and analysis of extracted IOLs. Participants and samples We report improved visual acuity when IOLs with severe glistening and SSNG were exchanged for clear IOLs in five patients. Methods Case reports. Main outcome measures The main outcome measure was visual acuity. The secondary outcome measure was light transmission. Explanted IOLs were subjected to investigation. Pre- and postoperative slit lamp images of the anterior eye and microscopic images of the extracted IOLs were taken and compared. Light transmission of the IOL was measured using a double beam type spectrophotometer. An integrated value of the percentage light transmittance in the visible light spectrum was calculated. Results We report on five patients whose visual acuity improved when IOLs were exchanged because of severe glistening and SSNG. All of the affected IOLs were MA60BM (Alcon, Forth Wroth Texas, USA) and the original implantation had occurred over a range of 6–15 years prior to the IOL exchange. Light transmission was decreased in all affected lenses compared to a similar control IOL. Conclusions Although only a few reports of cases in which glistening and SSNG have progressed to the level of decreased visual function have been published, the likelihood is that this phenomena will increase as the severity and incidence of these inclusions have been shown to increase with time. Appropriate evaluations of visual function in such patients are needed and consideration should be given to IOL exchange in symptomatic patients. PMID:26586975

Efficient Fair Exchange from Identity-Based Signature

NASA Astrophysics Data System (ADS)

Yum, Dae Hyun; Lee, Pil Joong

A fair exchange scheme is a protocol by which two parties Alice and Bob exchange items or services without allowing either party to gain advantages by quitting prematurely or otherwise misbehaving. To this end, modern cryptographic solutions use a semi-trusted arbitrator who involves only in cases where one party attempts to cheat or simply crashes. We call such a fair exchange scheme optimistic. When no registration is required between the signer and the arbitrator, we say that the fair exchange scheme is setup free. To date, the setup-free optimist fair exchange scheme under the standard RSA assumption was only possible from the generic construction of [12], which uses ring signatures. In this paper, we introduce a new setup-free optimistic fair exchange scheme under the standard RSA assumption. Our scheme uses the GQ identity-based signature and is more efficient than [12]. The construction can also be generalized by using various identity-based signature schemes. Our main technique is to allow each user to choose his (or her) own “random” public key in the identitybased signature scheme.

Generalization of the optimized-effective-potential model to include electron correlation: A variational derivation of the Sham-Schlueter equation for the exact exchange-correlation potential

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casida, M.E.

1995-03-01

The now classic optimized-effective-potential (OEP) approach of Sharp and Horton [Phys Rev. 90, 317 (1953)] and Talman and Shadwick [Phys. Rev. A 14, 36 (1976)] seeks the local potential that is variationally optimized to best approximate the Hartree-Fock exchange operator. The resulting OEP can be identified as the exchange potential of Kohn-Sham density-functional theory. The present work generalizes this OEP approach to treat the correlated case, and shows that the Kohn-Sham exchange-correlation potential is the variationally best local approximation to the exchange-correlation self-energy. This provides a variational derivation of the equation for the exact exchange-correlation potential that was derived bymore » Sham and Schlueter using a density condition. Implications for an approximate physical interpretation of the Kohn-Sham orbitals are discussesd. A correlated generalization of the Sharp-Horton--Krieger-Li-Iafrate [Phys Lett. A 146, 256 (1990)] approximation of the exchange potential is introduced in the quasiparticle limit.« less

Plasmapheresis for Preventing Complication of Hypertriglyceridemia: A Case Report and Review of Literature.

PubMed

Costantini, Nicoletta; Mameli, Antonella; Marongiu, Francesco

2016-01-01

Severe hypertriglyceridemia is a common indication for the need of plasma exchange in treatment of hypertriglyceridemic-induced pancreatitis when normal therapies fail to garner a response. Application of plasmapheresis to prevent complication of hypertriglyceridemia is limited because of its cost and availability. We present a case of a 44-year-old man with metabolic syndrome and a medical history of secondary polycythemia in obesity hypoventilation syndrome, whose laboratory tests revealed a triglycerides value of 3965 mg/dL. To prevent the complication of pancreatitis due to hypertriglyceridemia, we performed plasma exchange 3 times when conventional treatments did not sufficiently reduce the high level of triglycerides. A review of the current available literature was therefore conducted to provide an overview of the present data on apheretic treatment for patients with severe hypertriglyceridemia. Several case reports and case series have used plasmapheresis in acute treatment of hypertriglyceridemia pancreatitis related. In our case, the choice of plasmapheresis was applied in prevention of possible complications of hypertriglyceridemia.

Characterization of two-phase flow regimes in horizontal tubes using 81mKr tracer experiments.

PubMed

Oriol, Jean; Leclerc, Jean Pierre; Berne, Philippe; Gousseau, Georges; Jallut, Christian; Tochon, Patrice; Clement, Patrice

2008-10-01

The diagnosis of heat exchangers on duty with respect to flow mal-distributions needs the development of non-intrusive inlet-outlet experimental techniques in order to perform an online fault diagnosis. Tracer experiments are an example of such techniques. They can be applied to mono-phase heat exchangers but also to multi-phase ones. In this case, the tracer experiments are more difficult to perform. In order to check for the capabilities of tracer experiments to be used for the flow mal-distribution diagnosis in the case of multi-phase heat exchangers, we present here a preliminary study on the simplest possible system: two-phase flows in a horizontal tube. (81m)Kr is used as gas tracer and properly collimated NaI (TI) crystal scintillators as detectors. The specific shape of the tracer response allows two-phase flow regimes to be characterized. Signal analysis allows the estimation of the gas phase real average velocity and consequently of the liquid phase real average velocity as well as of the volumetric void fraction. These results are compared successfully to those obtained with liquid phase tracer experiments previously presented by Oriol et al. 2007. Characterization of the two-phase flow regimes and liquid dispersion in horizontal and vertical tubes using coloured tracer and no intrusive optical detector. Chem. Eng. Sci. 63(1), 24-34, as well as to those given by correlations from literature.

Health Information Exchange: What do patients want?

PubMed

Medford-Davis, Laura N; Chang, Lawrence; Rhodes, Karin V

2017-12-01

To determine whether emergency department patients want to share their medical records across health systems through Health Information Exchange and if so, whether they prefer to sign consent or share their records automatically, 982 adult patients presenting to an emergency department participated in a questionnaire-based interview. The majority (N = 906; 92.3%) were willing to share their data in a Health Information Exchange. Half (N = 490; 49.9%) reported routinely getting healthcare outside the system and 78.6 percent reported having records in other systems. Of those who were willing to share their data in a Health Information Exchange, 54.3 percent wanted to sign consent but 90 percent of those would waive consent in the case of an emergency. Privacy and security were primary concerns of patients not willing to participate in Health Information Exchange and preferring to sign consent. Improved privacy and security protections could increase participation, and findings support consideration of "break-the-glass" provider access to Health Information Exchange records in an emergent situation.

A general way of analyzing EPR spectroscopy for a pair of magnetically equivalent lanthanide ions in crystal: A case study of BaY2F8:Yb3+ crystal

NASA Astrophysics Data System (ADS)

Liu, Honggang; Zheng, Wenchen

2018-01-01

Electron paramagnetic resonance (EPR) is an important tool to study the complex interactions (e.g., exchange and magnetic dipole-dipole interactions) for a pair of lanthanide (Ln) ions in crystals. How to analyze these EPR spectra and obtain the strength of each interaction is a challenge for experimentalists. In this work, a general way of calculating the EPR lines for two magnetically equivalent Ln ions is given by us to solve this problem. In order to explain their EPR spectra and obtain exchange interaction parameters Ji (i = x, y, z) between them, we deduce the analytic formulas for computing the angular dependent EPR lines for such Ln pairs under the condition of weak coupling (|Ji| ≪ hv, where v is the microwave frequency in the EPR experiment) and set up the spin-Hamiltonian energy matrix that should be diagonalized to obtain these lines if intermediate (|Ji| ˜ hv) and strong (|Ji| > hv) couplings are encountered. To verify our method, the experimental EPR spectra for the Yb3+ doped BaY2F8 crystal are considered by us and the EPR lines from the isolated Yb3+ ion and Yb3+-Yb3+ pair with distance R equal to 0.371 nm are identified clearly. Moreover, exchange interaction parameters (Jx ≈ -0.04 cm-1, Jy ≈ -0.24 cm-1, and Jz ≈ -0.1 cm-1) for such a pair are also determined by our calculations. This case study demonstrates that the theoretical method given in this work would be useful and could be applied to understand interactions between Ln ions in crystals.

The role of the altruistic unbalanced chain in exchange living donor renal transplantation: single-center experience.

PubMed

Ahn, B K; Kwon, O J; Kang, C M

2012-01-01

The exchange donor program in renal transplantation is an efficient solution for recipients with a blood type or crossmatch-incompatible donor. However, this program has some difficulties to define unacceptable human leukocyte antigen matches, deteriorating clinical potential recipient condition, and withdrawal of donor consent. We analyzed the outcomes of exchange donor renal transplantation through the altruistic unbalanced chain. Among 152 cases of exchange donor renal transplantation from 1991 to 2010 in our hospital, we performed 58 procedures through altruistic unbalanced chains. We compared their outcomes with the direct and balanced chain group. We analyzed retrospectively whether this program expanded the donor pool, seeking better immunologic, size, and age matching. The graft survival and acute rejection rates did not differ significantly in the two groups. Of 152 cases, 58 (38.2%) renal transplantations were performed through an unbalanced chain. Seventeen waiting list recipients were transplanted through an altruistic unbalanced chain. In blood type O recipients (n = 32), the causes of registration in the exchange program were ABO incompatibility (93.3%), and positive crossmatch (6.7%). Nine altruistic blood type O donors and 9 (28.1%) type O recipients underwent transplantations through this chain. We suggest the altruistic unbalanced chain may expand the donor pool with advantages for difficult-to-match pairs. The disadvantages of type O recipients may be overcome through the use of an unbalanced chain. The altruistic unbalanced exchange transplantation program can help easy-to-match subjects, shortening the waiting periods. Copyright © 2012 Elsevier Inc. All rights reserved.

Investigation and optimization of the depth of flue gas heat recovery in surface heat exchangers

NASA Astrophysics Data System (ADS)

Bespalov, V. V.; Bespalov, V. I.; Melnikov, D. V.

2017-09-01

Economic issues associated with designing deep flue gas heat recovery units for natural gas-fired boilers are examined. The governing parameter affecting the performance and cost of surface-type condensing heat recovery heat exchangers is the heat transfer surface area. When firing natural gas, the heat recovery depth depends on the flue gas temperature at the condenser outlet and determines the amount of condensed water vapor. The effect of the outlet flue gas temperature in a heat recovery heat exchanger on the additionally recovered heat power is studied. A correlation has been derived enabling one to determine the best heat recovery depth (or the final cooling temperature) maximizing the anticipated reduced annual profit of a power enterprise from implementation of energy-saving measures. Results of optimization are presented for a surface-type condensing gas-air plate heat recovery heat exchanger for the climatic conditions and the economic situation in Tomsk. The predictions demonstrate that it is economically feasible to design similar heat recovery heat exchangers for a flue gas outlet temperature of 10°C. In this case, the payback period for the investment in the heat recovery heat exchanger will be 1.5 years. The effect of various factors on the optimal outlet flue gas temperature was analyzed. Most climatic, economical, or technological factors have a minor effect on the best outlet temperature, which remains between 5 and 20°C when varying the affecting factors. The derived correlation enables us to preliminary estimate the outlet (final) flue gas temperature that should be used in designing the heat transfer surface of a heat recovery heat exchanger for a gas-fired boiler as applied to the specific climatic conditions.

Kinetics of hydrogen/deuterium exchanges in cometary ices

NASA Astrophysics Data System (ADS)

Faure, Mathilde; Quirico, Eric; Faure, Alexandre; Schmitt, Bernard; Theulé, Patrice; Marboeuf, Ulysse

2015-11-01

The D/H composition of volatile molecules composing cometary ices brings key constraints on the origin of comets, on the extent of their presolar heritage, as well as on the origin of atmospheres and hydrospheres of terrestrial planets. Nevertheless, the D/H composition may have been modified to various extents in the nucleus when a comet approaches the Sun and experiences deep physical and chemical modifications in its subsurface. We question here the evolution of the D/H ratio of organic species by proton exchanges with water ice. We experimentally studied the kinetics of D/H exchanges on the ice mixtures H2O:CD3OD, H2O:CD3ND2 and D2O:HCN. Our results show that fast exchanges occur on the -OH and -NH2 chemical groups, which are processed through hydrogen bonds exchanges with water and by the molecular mobility triggered by structural changes, such as glass transition or crystallization. D/H exchanges kinetic is best described by a second-order kinetic law with activation energies of 4300 ± 900 K and 3300 ± 100 K for H2O:CD3OD and H2O:CD3ND2 ice mixtures, respectively. The corresponding pre-exponential factors ln(A(s-1)) are 25 ± 7 and 20 ± 1, respectively. No exchange was observed in the case of HCN trapped in D2O ice. These results strongly suggest that upon thermal heating (1) -OH and -NH2 chemical groups of any organic molecules loose their primordial D/H composition and equilibrate with water ice, (2) HCN does not experience proton transfer and keeps a primordial D/H composition and (3) C-H chemical groups are not isotopically modified.

Decadal changes in potassium, calcium, and magnesium in a deciduous forest soil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mulholland, Patrick J; Johnson, Dale W.; Todd Jr, Donald E

2008-01-01

Decadal changes in soil exchangeable K{sup +}, Ca{sup 2+}, and Mg{sup 2+} concentrations and contents from 1972 to 2004 in eight intensively monitored plots on Walker Branch Watershed were compared with estimates of increments or decrements in vegetation and detritus. The results from these eight plots compared favorably with those from a more extensive set from 24 soil sampling plots sampled in 1972 and 2004. Increases in exchangeable K{sup +} were noted between 1972 and 1982, but few changes were noted between 1982 and 2004 despite significant increments in vegetation and detritus and significant potential losses by leaching. Total Kmore » contents of soils in the 0- to 60-cm sampling depth were very large and a slight amount of weathering could have replenished the K{sup +} lost from exchanges sites. With one notable exception, exchangeable Ca{sup 2+} and Mg{sup 2+} concentrations and contents decreased continuously during the sampling period. Decreases in exchangeable Ca{sup 2+} could be attributed mostly to increments in biomass and detritus, whereas decreases in exchangeable Mg{sup 2+} could not and were attributed to leaching. The major exception to these patterns was in the case of exchangeable Ca{sup 2+}, where significant increases were noted in one plot and attributed to Ca release from the decomposition of Ca-rich coarse woody debris from oak (Quercus spp.) mortality. With minor exceptions, soils and changes in soils among the eight intensively sampled core plots were similar to those in a more extensive set of plots distributed across the watershed. This study shows that averaging among plots can mask significant and important spatial patterns in soil change that must be taken into account in assessing long-term trends.« less

Regional material flow accounting and environmental pressures: the Spanish case.

PubMed

Sastre, Sergio; Carpintero, Óscar; Lomas, Pedro L

2015-02-17

This paper explores potential contributions of regional material flow accounting to the characterization of environmental pressures. With this aim, patterns of material extraction, trade, consumption, and productivity for the Spanish regions were studied within the 1996-2010 period. The main methodological variation as compared to whole-country based approaches is the inclusion of interregional trade, which can be separately assessed from the international exchanges. Each region was additionally profiled regarding its commercial exchanges with the rest of the regions and the rest of the world and the related environmental pressures. Given its magnitude, interregional trade is a significant source of environmental pressure. Most of the exchanges occur across regions and different extractive and trading patterns also arise at this scale. These differences are particularly great for construction minerals, which in Spain represent the largest share of extracted and consumed materials but do not cover long distances, so their impact is visible mainly at the regional level. During the housing bubble, economic growth did not improve material productivity.

Assessment of Thermal Performance of Functionally Graded Materials in Longitudinal Fins

NASA Astrophysics Data System (ADS)

Hassanzadeh, R.; Bilgili, M.

2018-01-01

Assessment of the thermal characteristics of materials in heat exchangers with longitudinal fins is performed in the case where a conventional homogeneous material of a longitudinal fin is replaced by a functionally graded one, in which the fin material properties, such as the conductivity, are assumed to be graded as linear and power-law functions along the normal axis from the fin base to the fin tip. The resulting equations are calculated under two (Dirichlet and Neumann) boundary conditions. The equations are solved by an approximate analytical method with the use of the mean value theorem. The results show that the inhomogeneity index of a functionally graded material plays an important role for the thermal energy characteristics in such heat exchangers. In addition, it is observed that the use of such a material in longitudinal fins enhances the rate of heat transfer between the fin surface and surrounding fluid. Hopefully, the results obtained in the study will arouse interest of designers in heat exchange industry.

Mapping transiently formed and sparsely populated conformations on a complex energy landscape

PubMed Central

Wang, Yong; Papaleo, Elena; Lindorff-Larsen, Kresten

2016-01-01

Determining the structures, kinetics, thermodynamics and mechanisms that underlie conformational exchange processes in proteins remains extremely difficult. Only in favourable cases is it possible to provide atomic-level descriptions of sparsely populated and transiently formed alternative conformations. Here we benchmark the ability of enhanced-sampling molecular dynamics simulations to determine the free energy landscape of the L99A cavity mutant of T4 lysozyme. We find that the simulations capture key properties previously measured by NMR relaxation dispersion methods including the structure of a minor conformation, the kinetics and thermodynamics of conformational exchange, and the effect of mutations. We discover a new tunnel that involves the transient exposure towards the solvent of an internal cavity, and show it to be relevant for ligand escape. Together, our results provide a comprehensive view of the structural landscape of a protein, and point forward to studies of conformational exchange in systems that are less characterized experimentally. DOI: http://dx.doi.org/10.7554/eLife.17505.001 PMID:27552057

Three-Stage Production Cost Modeling Approach for Evaluating the Benefits of Intra-Hour Scheduling between Balancing Authorities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samaan, Nader A.; Milligan, Michael; Hunsaker, Matthew

This paper introduces a Production Cost Modeling (PCM) approach to evaluate the benefits of intra-hour scheduling between Balancing Authorities (BAs). The system operation is modeled in a three-stage sequential manner: day ahead (DA)-hour ahead (HA)-real time (RT). In addition to contingency reserve, each BA will need to carry out “up” and “down” load following and regulation reserve capacity requirements in the DA and HA time frames. In the real-time simulation, only contingency and regulation reserves are carried out as load following is deployed. To model current real-time operation with hourly schedules, a new constraint was introduced to force each BAmore » net exchange schedule deviation from HA schedules to be within NERC ACE limits. Case studies that investigate the benefits of moving from hourly exchange schedules between WECC BAs into 10-min exchange schedules under two different levels of wind and solar penetration (11% and 33%) are presented.« less

Three-Stage Production Cost Modeling Approach for Evaluating the Benefits of Intra-Hour Scheduling Between Balancing Authorities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samaan, Nader; Milligan, Michael; Hunsaker, Matt

This paper introduces a production cost modeling approach for evaluating the benefits of intra-hour scheduling among Balancing Authorities (BAs). System operation is modeled in a three-stage sequential manner: day ahead (DA)-hour ahead (HA) real time (RT). In addition to contingency reserve, each BA will need to carry out 'up' and 'down' load following and regulation reserve capacity requirements in the DA and HA time frames. In the RT simulation, only contingency and regulation reserves are carried out as load following is deployed. To model current RT operation with hourly schedules, a new constraint was introduced to force each BA netmore » exchange schedule deviation from HA schedules to be within North American Electric Reliability Corporation (NERC) area control error (ACE) limits. Case studies that investigate the benefits of moving from hourly exchange schedules between Western Electricity Coordinating Council (WECC) BAs into 10-minute exchange schedules under two different levels of wind and solar penetration (11% and 33%) are presented.« less

Nuclear mtDNA pseudogenes as a source of new variants of mitochondrial genes: A case study of Siberian rubythroat Luscinia calliope (muscicapidae, aves).

PubMed

Spiridonova, L N; Red'kin, Ya A; Valchuk, O P

2016-01-01

First evidence for the presence of copies of mitochondrial cytochrome b gene of the subspecies group Luscinia calliope anadyrensis-L. c. camtschatkensis in the nuclear genome of nominative L. c. calliope was obtained, which indirectly indicates the nuclear origin of the subspecies-specific mitochondrial haplotypes in Siberian rubythroat. This fact clarifies the appearance of mitochondrial haplotypes of eastern subspecies by exchange between the homologous regions of the nuclear and mitochondrial genomes followed by fixation by the founder effect. This is the first study to propose a mechanism of DNA fragment exchange between the nucleus and mitochondria (intergenomic recombination) and to show the role of nuclear copies of mtDNA as a source of new taxon-specific mitochondrial haplotypes, which implies their involvement in the microevolutionary processes and morphogenesis.

Fast Collisional Lipid Transfer Among Polymer-Bounded Nanodiscs

NASA Astrophysics Data System (ADS)

Cuevas Arenas, Rodrigo; Danielczak, Bartholomäus; Martel, Anne; Porcar, Lionel; Breyton, Cécile; Ebel, Christine; Keller, Sandro

2017-04-01

Some styrene/maleic acid (SMA) copolymers solubilise membrane lipids and proteins to form polymer-bounded nanodiscs termed SMA/lipid particles (SMALPs). Although SMALPs preserve a lipid-bilayer core, they appear to be more dynamic than other membrane mimics. We used time-resolved Förster resonance energy transfer and small-angle neutron scattering to determine the kinetics and the mechanisms of phospholipid transfer among SMALPs. In contrast with vesicles or protein-bounded nanodiscs, SMALPs exchange lipids not only by monomer diffusion but also by fast collisional transfer. Under typical experimental conditions, lipid exchange occurs within seconds in the case of SMALPs but takes minutes to days in the other bilayer particles. The diffusional and second-order collisional exchange rate constants for SMALPs at 30 °C are kdif = 0.287 s-1 and kcol = 222 M-1s-1, respectively. Together with the fast kinetics, the observed invariability of the rate constants with probe hydrophobicity and the moderate activation enthalpy of ~70 kJ mol-1 imply that lipids exchange through a “hydrocarbon continuum” enabled by the flexible nature of the SMA belt surrounding the lipid-bilayer core. Owing to their fast lipid-exchange kinetics, SMALPs represent highly dynamic equilibrium rather than kinetically trapped membrane mimics, which has important implications for studying protein/lipid interactions in polymer-bounded nanodiscs.

A population ecology perspective on the functioning and future of health information organizations.

PubMed

Vest, Joshua R; Menachemi, Nir

2017-11-01

Increasingly, health care providers need to exchange information to meet policy expectations and business needs. A variety of health information organizations (HIOs) provide services to facilitate health information exchange (HIE). However, the future of these organizations is unclear. The aim of this study was to explore the environmental context, potential futures, and survivability of community HIOs, enterprise HIEs, and electronic health record vendor-mediated exchange using the population ecology theory. Qualitative interviews with 33 key informants representing each type of HIE organization were analyzed using template analysis. Community HIOs, enterprise HIEs, and electronic health record vendors exhibited a high degree of competition for resources, especially in the area of exchange infrastructure services. Competition resulted in closures in some areas. In response to environmental pressures, each organizational type was endeavoring to differentiate its services and unique use case, as well as pursing symbiotic relationships or attempting resource partitioning. HIOs compete for similar resources and are reacting to environmental pressures to better position themselves for continued survival and success. Our ecological research perspective helps move the discourse away from situation of a single exchange organization type toward a view of the broader dynamics and relationships of all organizations involved in facilitating HIE activities. HIOs are attempting to partition the environment and differentiate services. HIE options should not be construed as an "either/or" decision, but one where multiple and complementary participation may be required.

Hyperpolarized Xenon-129 Gas-Exchange Imaging of Lung Microstructure: First Case Studies in Subjects with Obstructive Lung Disease

PubMed Central

Dregely, Isabel; Mugler, John P.; Ruset, Iulian C.; Altes, Talissa A.; Mata, Jaime F.; Miller, G. Wilson; Ketel, Jeffrey; Ketel, Steve; Distelbrink, Jan; Hersman, F.W.; Ruppert, Kai

2011-01-01

Purpose To develop and test a method to non-invasively assess the functional lung microstructure. Materials and Methods The Multiple exchange time Xenon polarization Transfer Contrast technique (MXTC) encodes xenon gas-exchange contrast at multiple delay times permitting two lung-function parameters to be derived: 1) MXTC-F, the long exchange-time depolarization value, which is proportional to the tissue to alveolar-volume ratio and 2) MXTC-S, the square root of the xenon exchange-time constant, which characterizes thickness and composition of alveolar septa. Three healthy volunteers, one asthmatic and two COPD (GOLD stage I and II) subjects were imaged with MXTC MRI. In a subset of subjects, hyperpolarized xenon-129 ADC MRI and CT imaging were also performed. Results The MXTC-S parameter was found to be elevated in subjects with lung disease (p-value = 0.018). In the MXTC-F parameter map it was feasible to identify regional loss of functional tissue in a COPD patient. Further, the MXTC-F map showed excellent regional correlation with CT and ADC (ρ ≥ 0.90) in one COPD subject. Conclusion The functional tissue-density parameter MXTC-F showed regional agreement with other imaging techniques. The newly developed parameter MXTC-S, which characterizes the functional thickness of alveolar septa, has potential as a novel biomarker for regional parenchymal inflammation or thickening. PMID:21509861

Open inquiry-based learning experiences: a case study in the context of energy exchange by thermal radiation

NASA Astrophysics Data System (ADS)

Pizzolato, Nicola; Fazio, Claudio; Rosario Battaglia, Onofrio

2014-01-01

An open inquiry (OI)-based teaching/learning experience, regarding a scientific investigation of the process of energy exchange by thermal radiation, is presented. A sample of upper secondary school physics teachers carried out this experience at the University of Palermo, Italy, in the framework of ESTABLISH, a FP7 European Project aimed at promoting and developing inquiry-based science education. The teachers had the opportunity to personally experience an OI-based learning activity, with the aim of exploring the pedagogical potentialities of this teaching approach to promote both the understanding of difficult concepts and a deeper view of scientific practices. The teachers were firstly engaged in discussions concerning real-life problematic situations, and then stimulated to design and carry out their own laboratory activities, aimed at investigating the process of energy exchange by thermal radiation. A scientific study on the energy exchange between a powered resistor and its surrounding environment, during the heating and cooling processes, was designed and performed. Here we report the phases of this experiment by following the teachers' perspective. A structured interview conducted both before and after the OI experience allowed us to analyze and point out the teachers' feedback from a pedagogical point of view. The advantages and limits of an OI-based approach to promote the development of more student-centred inquiry-oriented teaching strategies are finally discussed.

The thermodynamic and hydrodynamic properties of macromolecules that influence the hydrodynamics of porous systems.

PubMed

Comper, W D

1994-06-21

The water flow across porous, semipermeable membranes associated with osmosis and filtration under a variety of conditions is analysed and compared to macromolecular diffusion across free-liquid boundaries, diffusion and sedimentation in the ultracentrifuge, and tracer diffusion of water. This study establishes that osmosis can be explained in terms of the irreversible thermodynamics of diffusion. For macromolecular osmotically active solutes in the semidilute concentration regime the water flows across semipermeable porous membranes are interpreted in terms of a rate-limiting solute-solvent exchange layer that exists on the solution side of the membrane adjacent to the membrane pore; both osmosis and filtration will be governed by these exchange layers. These exchange layers also yield unique properties of their constituent molecules in systems where there is osmotic equilibration between solutions of different solutes. This study also establishes the need to consider the internal osmotic pressure of membranes in the pressure balance associated with the flow across the membrane. The complex situation of partially permeable membranes is analysed for the simple case where there are no mechanical gradients and there is only one osmotically active solution that creates a rate-limiting exchange layer. This treatment predicts that the flow will be governed primarily by the osmotic pressure difference associated with the partitioning of the solute at the membrane-solution interface.

The dynamical behavior of the s-trioxane radical cation-A low-temperature EPR and theoretical study.

PubMed

Naumov, Sergej S; Knolle, Wolfgang; Naumov, Sergej P; Pöppl, Andreas; Janovský, Igor

2014-10-28

The radical cation of s-trioxane, radiolytically generated in a freon (CF3CCl3) matrix, was studied in the 10-140 K temperature region. Reversible changes of the EPR spectra were observed, arising from both ring puckering and ring inversion through the molecular plane. The ESREXN program based on the Liouville density matrix equation, allowing the treatment of dynamical exchange, has been used to analyze the experimental results. Two limiting conformer structures of the s-trioxane radical cation were taken into account, namely "rigid" half-boat and averaged planar ones, differing strongly in their electron distribution. The spectrum due to the "rigid" half-boat conformer can be observed only at very low (<60 K) temperatures, when the exchange of conformers is very slow. Two transition states for interconversion by puckering and ring-inversion were identified, close in activation energy (2.3 and 3.0 kJ/mol calculated). Since the energy difference is very small, both processes set on at a comparable temperature. In the case of nearly complete equilibration (fast exchange) between six energetically equivalent structures at T > 120 K in CF3CCl3, a septet due to six equivalent protons (hfs splitting constant 5.9 mT) is observed, characteristic of the dynamically averaged planar geometry of the radical cation. DFT quantum chemical calculations and spectral simulation including intramolecular dynamical exchange support the interpretation.

Photodissociation dynamics of gaseous CpCo(CO)2 and ligand exchange reactions of CpCoH2 with C3H4, C3H6, and NH3.

PubMed

Oana, Melania; Nakatsuka, Yumiko; Albert, Daniel R; Davis, H Floyd

2012-05-31

The photodissociation dynamics of CpCo(CO)(2) was studied in a molecular beam using photofragment translational energy spectroscopy with 157 nm photoionization detection of the metallic products. At 532 and 355 nm excitation, the dominant one-photon channel involved loss of a single CO ligand producing CpCoCO. The product angular distributions were isotropic, and a large fraction of excess energy appeared as product vibrational excitation. Production of CpCO + 2CO resulted from two-photon absorption processes. The two-photon dissociation of mixtures containing CpCo(CO)(2) and H(2) at the orifice of a pulsed nozzle was used to produce a novel 16-electron unsaturated species, CpCoH(2). Transition metal ligand exchange reactions, CpCoH(2) + L → CpCoL + H(2) (L = propyne, propene, or ammonia), were studied under single-collision conditions for the first time. In all cases, ligand exchange occurred via 18-electron association complexes with lifetimes comparable to their rotational periods. Although ligand exchange reactions were not detected from CpCoH(2) collisions with methane or propane (L = CH(4) or C(3)H(8)), a molecular beam containing CpCoCH(4) was produced by photolysis of mixtures containing CpCo(CO)(2) and CH(4).

Modeling circulation patterns induced by spatial cross-shore wind variability in a small-size coastal embayment

NASA Astrophysics Data System (ADS)

Cerralbo, Pablo; Espino, Manuel; Grifoll, Manel

2016-08-01

This contribution shows the importance of the cross-shore spatial wind variability in the water circulation in a small-sized micro-tidal bay. The hydrodynamic wind response at Alfacs Bay (Ebro River delta, NW Mediterranean Sea) is investigated with a numerical model (ROMS) supported by in situ observations. The wind variability observed in meteorological measurements is characterized with meteorological model (WRF) outputs. From the hydrodynamic simulations of the bay, the water circulation response is affected by the cross-shore wind variability, leading to water current structures not observed in the homogeneous-wind case. If the wind heterogeneity response is considered, the water exchange in the longitudinal direction increases significantly, reducing the water exchange time by around 20%. Wind resolutions half the size of the bay (in our case around 9 km) inhibit cross-shore wind variability, which significantly affects the resultant circulation pattern. The characteristic response is also investigated using idealized test cases. These results show how the wind curl contributes to the hydrodynamic response in shallow areas and promotes the exchange between the bay and the open sea. Negative wind curl is related to the formation of an anti-cyclonic gyre at the bay's mouth. Our results highlight the importance of considering appropriate wind resolution even in small-scale domains (such as bays or harbors) to characterize the hydrodynamics, with relevant implications in the water exchange time and the consequent water quality and ecological parameters.

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2013-12-17

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Federal Register 2010, 2011, 2012, 2013, 2014

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Federal Register 2010, 2011, 2012, 2013, 2014

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INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY: Solvable Catalyzed Birth-Death-Exchange Competition Model of Three Species

NASA Astrophysics Data System (ADS)

Wang, Hai-Feng; Lin, Zhen-Quan; Gao, Yan; Zhang, Heng

2009-10-01

A competition model of three species in exchange-driven aggregation growth is proposed. In the model, three distinct aggregates grow by exchange of monomers and in parallel, birth of species A is catalyzed by species B and death of species A is catalyzed by species C. The rates for both catalysis processes are proportional to kjν and kjω respectively, where ν(Ω) is a parameter reflecting the dependence of the catalysis reaction rate of birth (death) on the catalyst aggregate's size. The kinetic evolution behaviors of the three species are investigated by the rate equation approach based on the mean-field theory. The form of the aggregate size distribution of A-species ak(t) is found to be dependent crucially on the two catalysis rate kernel parameters. The results show that (i) in case of μ <= 0, the form of ak(t) mainly depends on the competition between self-exchange of species A and species-C-catalyzed death of species A; (ii) in case of ν > 0, the form of ak(t) mainly depends on the competition between species-B-catalyzed birth of species A and species-C-catalyzed death of species A.

Sn-Mesoporphyrin interdiction of severe hyperbilirubinemia in Jehovah's Witness newborns as an alternative to exchange transfusion.

PubMed

Kappas, A; Drummond, G S; Munson, D P; Marshall, J R

2001-12-01

The religious convictions of parents who are Jehovah's Witness adherents lead them to reject the use of exchange transfusions as therapy for severe hyperbilirubinemia in newborns in whom intensive phototherapy has failed to control this problem. Consequently, physicians caring for such infants may be obliged to initiate legal action to compel use of the procedure when severe hyperbilirubinemia not sufficiently responsive to phototherapy warrants an exchange transfusion. Our goal was to determine if we could use the potent inhibitor of bilirubin production, Sn-Mesoporphyrin (SnMP), to resolve the troubling medical-legal issues in such situations in 2 infants with hemolytic disease of the newborn who required exchange transfusions for severe hyperbilirubinemia but whose Jehovah's Witness parents rejected the procedure. SnMP was administered in a single dose, as in previous studies, at the time when exchange transfusion would have been initiated and plasma bilirubin levels were monitored at close intervals thereafter. SnMP is a potent inhibitor of heme oxygenase, the rate-limiting enzyme in catabolism of heme to bilirubin. We found in earlier studies that in single doses of 6 micromol/kg birth weight, SnMP is extremely effective in moderating the course of hyperbilirubinemia and in eliminating the need for supplemental phototherapy in jaundiced newborns. In the 2 cases described, a single dose of SnMP (6 micromol/kg birth weight) was administered intramuscularly to severely jaundiced infants with immune hemolysis at a time when clinical circumstances dictated the need for exchange transfusion. CASE 1: This patient was a preterm male infant (gestational age: 35 5/7 weeks; birth weight: 2790 g) whose plasma bilirubin concentration (PBC) at 1 hour after birth was 5.0 mg/dL. Despite intensive phototherapy with 3 banks of lights and 1 biliblanket, the PBC increased steadily with no diminution in the rate of increase for 75 hours. In view of the problems of immune hemolysis, and prematurity, and the inability of phototherapy to stop progression of hyperbilirubinemia, a decision to carry out an exchange transfusion was made; the decision was, however, rejected by the Jehovah's Witness parents. Pending legal action to compel use of the procedure, a request to this (Rockefeller) laboratory for SnMP was made; its use was approved by the Food and Drug Administration; and the inhibitor was delivered to the physician-in-charge (D.P.M.) in Sioux Falls, South Dakota. The single dose of SnMP was administered to the infant at 75 hours after birth; the course of hyperbilirubinemia before and after the use of the inhibitor is shown in Fig 1. [figure: see text]. CASE 2: This female term infant (gestational age: 38-39 weeks; birth weight: 4140 g) with immune hemolysis was delivered by cesarean section and because of problems related to meconium aspiration required helicopter transfer to the Special Care Nursery in Abilene, Texas, where 10 hours after birth the first PBC was determined to be 18.0 mg/dL. Double-bank phototherapy plus a biliblanket was initiated; a third bank of lights was later ordered. The PBC fluctuated in the ensuing 2 days between 13.8 to 25.8 mg/dL during which suggestive clinical signs of possible bilirubin encephalopathy became manifest. In view of the clinical circumstances and the continued severe hyperbilirubinemia, permission for a double-exchange transfusion was requested. The parents, who were Jehovah's Witness adherents, refused the procedure. While preparing legal action to compel use of the exchange, a request was made to this (Rockefeller) laboratory for use of SnMP to attempt control of hyperbilirubinemia. With FDA approval, the SnMP was delivered to the attending neonatologist (J. R. M.) in Abilene and administered in a single dose (6 micromol/kg birth weight) at 56 hours after birth when the PBC was 19.5 mg/dL. The course of bilirubinemia before and after SnMP use is shown in Fig 2. [figure: see text]. The use of SnMP to moderate or prevent the development of severe hyperbilirubinemia in newborns (preterm, near-term, term with high PBCs [15-18 mg/dL], ABO-incompatibility; glucose-6-phosphate dehydrogenase deficiency) has been extensively studied in carefully conducted clinical trials the results of which have been reported earlier. This inhibitor of bilirubin production has demonstrated marked efficacy in moderating the course of hyperbilirubinemia in all diagnostic groups of unconjugated neonatal jaundice. The 2 cases described in this report confirmed the efficacy of SnMP in terminating progression of hyperbilirubinemia in infants in whom phototherapy had failed to sufficiently control the problem and whose parents, for religious reasons, would not permit exchange transfusions. Interdiction of severe hyperbilirubinemia by inhibiting the production of bilirubin with SnMP can be an effective alternative to the use of exchange transfusion in the management of severe newborn jaundice that has not responded sufficiently to light treatment to ease concern about the development of bilirubin encephalopathy.

Summary and evaluation of the parametric study of potential early commercial MHD power plants (PSPEC)

NASA Technical Reports Server (NTRS)

Staigner, P. J.; Abbott, J. M.

1980-01-01

Two parallel contracted studies were conducted. Each contractor investigated three base cases and parametric variations about these base cases. Each contractor concluded that two of the base cases (a plant using separate firing of an advanced high temperature regenerative air heater with fuel from an advanced coal gasifier and a plant using an intermediate temperature metallic recuperative heat exchanger to heat oxygen enriched combustion air) were comparable in both performance and cost of electricity. The contractors differed in the level of their cost estimates with the capital cost estimates for the MHD topping cycle and the magnet subsystem in particular accounting for a significant part of the difference. The impact of the study on the decision to pursue a course which leads to an oxygen enriched plant as the first commercial MHD plant is described.

Open-Source Software in Computational Research: A Case Study

DOE PAGES

Syamlal, Madhava; O'Brien, Thomas J.; Benyahia, Sofiane; ...

2008-01-01

A case study of open-source (OS) development of the computational research software MFIX, used for multiphase computational fluid dynamics simulations, is presented here. The verification and validation steps required for constructing modern computational software and the advantages of OS development in those steps are discussed. The infrastructure used for enabling the OS development of MFIX is described. The impact of OS development on computational research and education in gas-solids flow, as well as the dissemination of information to other areas such as geophysical and volcanology research, is demonstrated. This study shows that the advantages of OS development were realized inmore » the case of MFIX: verification by many users, which enhances software quality; the use of software as a means for accumulating and exchanging information; the facilitation of peer review of the results of computational research.« less

A roadmap for knowledge exchange and mobilization research in conservation and natural resource management.

PubMed

Nguyen, Vivian M; Young, Nathan; Cooke, Steven J

2017-08-01

Scholars across all disciplines have long been interested in how knowledge moves within and beyond their community of peers. Rapid environmental changes and calls for sustainable management practices mean the best knowledge possible is needed to inform decisions, policies, and practices to protect biodiversity and sustainably manage vulnerable natural resources. Although the conservation literature on knowledge exchange (KE) and knowledge mobilization (KM) has grown in recent years, much of it is based on context-specific case studies. This presents a challenge for learning cumulative lessons from KE and KM research and thus effectively using knowledge in conservation and natural resources management. Although continued research on the gap between knowledge and action is valuable, overarching conceptual frameworks are now needed to enable summaries and comparisons across diverse KE-KM research. We propose a knowledge-action framework that provides a conceptual roadmap for future research and practice in KE/KM with the aim of synthesizing lessons learned from contextual case studies and guiding the development and testing of hypotheses in this domain. Our knowledge-action framework has 3 elements that occur at multiple levels and scales: knowledge production (e.g., academia and government), knowledge mediation (e.g., knowledge networks, actors, relational dimension, and contextual dimension), and knowledge-based action (e.g., instrumental, symbolic, and conceptual). The framework integrates concepts from the sociology of science in particular, and serves as a guide to further comprehensive understanding of knowledge exchange and mobilization in conservation and sustainable natural resource management. © 2016 Society for Conservation Biology.

Lessons Learned on Communication and Engagement for Educator Evaluation: Colorado Case Study. Policy-to-Practice Brief

ERIC Educational Resources Information Center

Behrstock-Sherratt, Ellen; Biggers, Kietha; Fetters, Jenni

2012-01-01

With many efforts underway across the United States, state education agency (SEA) leaders have the opportunity to utilize the expertise of their contacts in other SEAs and regional comprehensive centers (RCCs) in their region and throughout the country to exchange ideas and share the lessons they have learned about involving stakeholders in…

Economic Liberalism and Regional Security in East Asia: A Case Study on the Impact of China’s Accession to the WTO

DTIC Science & Technology

2010-12-10

well-being. A common measure is the level of bilateral and intra-regional trade, while other measures such as capital flows and foreign direct...Rising Star, 5. 40Zhongwei Lu, “On China-U.S.-Japan Trilateral Relations: Comments on Their Recent Exchanges of Top- level Visits,” Contemporary

The Application of PECS in a Deaf Child with Autism: A Case Study

ERIC Educational Resources Information Center

Malandraki, Georgia A.; Okalidou, Areti

2007-01-01

A 10-year-old nonverbal Greek boy, C.Z., who had been diagnosed with both bilateral sensorineural profound hearing loss and autism, was taught to use the Picture Exchange Communication System (PECS), with some modifications and extensions, over a 4-month intensive intervention period. C.Z.'s original communication and behavioral status as well as…

Attesting Adios! Airways' XBRL Filings: A Case Study on Performing Agreed-Upon Procedures

ERIC Educational Resources Information Center

Farewell, Stephanie; Debreceny, Roger

2012-01-01

On 30 January 2009, the Securities and Exchange Commission (SEC) released Rule 33-9002. This rule phased in the required use of XBRL. The accuracy of mapping financial statement line items to the US GAAP taxonomy and the tagging of the financial statement facts are of fundamental importance to the accuracy of the XBRL instance document. Currently,…

Integration of the subsurface and the surface sectors for a more holistic approach for sustainable redevelopment of urban brownfields.

PubMed

Norrman, Jenny; Volchko, Yevheniya; Hooimeijer, Fransje; Maring, Linda; Kain, Jaan-Henrik; Bardos, Paul; Broekx, Steven; Beames, Alistair; Rosén, Lars

2016-09-01

This paper presents a holistic approach to sustainable urban brownfield redevelopment where specific focus is put on the integration of a multitude of subsurface qualities in the early phases of the urban redevelopment process, i.e. in the initiative and plan phases. Achieving sustainability in brownfield redevelopment projects may be constrained by a failure of engagement between two key expert constituencies: urban planners/designers and subsurface engineers, leading to missed opportunities and unintended outcomes in the plan realisation phase. A more integrated approach delivers greater benefits. Three case studies in the Netherlands, Belgium and Sweden were used to test different sustainability assessment instruments in terms of the possibility for knowledge exchange between the subsurface and the surface sectors and in terms of cooperative learning among experts and stakeholders. Based on the lessons learned from the case studies, a generic decision process framework is suggested that supports holistic decision making. The suggested framework focuses on stakeholder involvement, communication, knowledge exchange and learning and provides an inventory of instruments that can support these processes. Copyright © 2016 Elsevier B.V. All rights reserved.

Designing a Care Pathway Model – A Case Study of the Outpatient Total Hip Arthroplasty Care Pathway

PubMed Central

Oosterholt, Robin I; Boess, Stella U; Vehmeijer, Stephan BW

2017-01-01

Introduction: Although the clinical attributes of total hip arthroplasty (THA) care pathways have been thoroughly researched, a detailed understanding of the equally important organisational attributes is still lacking. The aim of this article is to contribute with a model of the outpatient THA care pathway that depicts how the care team should be organised to enable patient discharge on the day of surgery. Theory: The outpatient THA care pathway enables patients to be discharged on the day of surgery, shortening the length of stay and intensifying the provision and organisation of care. We utilise visual care modelling to construct a visual design of the organisation of the care pathway. Methods: An embedded case study was conducted of the outpatient THA care pathway at a teaching hospital in the Netherlands. The data were collected using a visual care modelling toolkit in 16 semi-structured interviews. Problems and inefficiencies in the care pathway were identified and addressed in the iterative design process. Results: The results are two visual models of the most critical phases of the outpatient THA care pathway: diagnosis & preparation (1) and mobilisation & discharge (4). The results show the care team composition, critical value exchanges, and sequence that enable patient discharge on the day of surgery. Conclusion: The design addressed existing problems and is an optimisation of the case hospital’s pathway. The network of actors consists of the patient (1), radiologist (1), anaesthetist (1), nurse specialist (1), pharmacist (1), orthopaedic surgeon (1,4), physiotherapist (1,4), nurse (4), doctor (4) and patient application (1,4). The critical value exchanges include patient preparation (mental and practical), patient education, aligned care team, efficient sequence of value exchanges, early patient mobilisation, flexible availability of the physiotherapist, functional discharge criteria, joint decision making and availability of the care team. PMID:29042844

A novel association of acquired ADAMTS13 inhibitor and acute dengue virus infection

PubMed Central

Rossi, Fernanda C.; Angerami, Rodrigo N.; de Paula, Erich V.; Orsi, Fernanda L.; Shang, Dezhi; del Guercio, Vânia M.; Resende, Mariângela R.; Annichino-Bizzacchi, Joyce M.; da Silva, Luiz J.; Zheng, X. Long; Castro, Vagner

2011-01-01

BACKGROUND Dengue is a mosquito-borne viral disease with an increasing incidence worldwide. Thrombocytopenia is a common finding in dengue virus (DV) infection; however, the underlying mechanisms remain unknown. CASE REPORT Here we provide the first evidence of a case of antibody formation against ADAMTS13 (ADAMTS13 inhibitor) in the course of a severe acute DV infection resulting in thrombotic microangiopathy (TMA). The patient presented with classical dengue symptoms (positive epidemiology, high fever, myalgia, predominantly in the lower limbs and lumbar region for 1 week) and, after 11 days of initial symptoms, developed TMA. Clinical and laboratorial investigation of dengue and TMA was performed. RESULTS The patient presented with ADAMTS13 inhibitor (IgG) during the acute phase of the disease, without anti-platelet antibodies detectable. Dengue infection had laboratorial confirmation. There were excellent clinical and laboratory responses to 11 serial plasma exchanges. Anti-ADAMTS13 inhibitor disappeared after remission of TMA and dengue resolution. No recurrence of TMA symptoms was observed after 2-year follow-up. CONCLUSIONS Although the real incidence of dengue-related TMA is unknown, this case provides the basis for future epidemiologic studies on acquired ADAMTS13 deficiency in DV infection. The prompt clinical recognition of this complication and early installment of specific therapy with plasma exchange are likely to improve the outcome of severe cases of dengue. PMID:19788513

Human health tradeoffs in wellhead drinking water treatment: Comparing exposure reduction to embedded life cycle risks.

PubMed

Gifford, Mac; Chester, Mikhail; Hristovski, Kiril; Westerhoff, Paul

2018-01-01

Treatment of drinking water decreases human health risks by reducing pollutants, but the required materials, chemicals, and energy emit pollutants and increase health risks. We explored human carcinogenic and non-carcinogenic disease tradeoffs of water treatment by comparing pollutant dose-response curves against life cycle burden using USEtox methodology. An illustrative wellhead sorbent groundwater treatment system removing hexavalent chromium or pentavalent arsenic serving 3200 people was studied. Reducing pollutant concentrations in drinking water from 20 μg L -1 to 10 μg L -1 avoided 37 potential cancer cases and 64 potential non-cancer disease cases. Human carcinogenicity embedded in treatment was 0.2-5.3 cases, and non-carcinogenic toxicity was 0.2-14.3 cases, depending on technology and degree of treatment. Embedded toxicity impacts from treating Cr(VI) using strong-base anion exchange were <10% of those from using weak base anion exchange. Acidification and neutralization contributed >90% of the toxicity impacts for treatment options requiring pH control. In scenarios where benefits exceeded burdens, tradeoffs still existed. Benefits are experienced by a local population but burdens are born externally where the materials and energy are produced, thus exporting the health risks. Even when burdens clearly exceeded benefits, cost considerations may still drive selecting a detrimental treatment level or technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

Oral to nasal tube exchange under fibroscopic view: a new technique for nasal intubation in a predicted difficult airway.

PubMed

Monclus, Enric; Garcés, Antonio; Artés, David; Mabrock, Maged

2008-07-01

For a predicted difficult airway, oral intubation techniques are well established in pediatric anesthesia, but nasotracheal intubation remains a problem. There are many reports concerning this, but the risk of bleeding, added to the lack of cooperation make this procedure difficult and hazardous. We describe a modification of the nasal intubation technique in two stages. First an oral intubation and then exchanging the oral for a nasal tube, in the case of a 13-year-old boy affected by an advanced stage of cherubism. Oral intubation using a laryngeal mask technique has already been reported, but problems appear during the exchange procedure and even more when direct laryngoscopy is impossible. Fiberscopic control of the exchange, and the introduction of a Cook Exchange Catheter into the trachea through the oral tube before withdrawal, permits oxygenation of the patient and acts as a guide for oral tube reintroduction if required.

Kinetic theory of oxygen isotopic exchange between minerals and water

USGS Publications Warehouse

Criss, R.E.; Gregory, R.T.; Taylor, H.P.

1987-01-01

Kinetic and mass conservation equations are used to describe oxygen isotopic exchange between minerals and water in "closed" and open hydrothermal systems. In cases where n coexisting mineral phases having different reaction rates are present, the exchange process is described by a system of n + 1 simultaneous differential equations consisting of n pseudo first-order rate equations and a conservation of mass equation. The simultaneous solutions to these equations generate curved exchange trajectories on ??-?? plots. Families of such trajectories generated under conditions allowing for different fluid mole fractions, different fluid isotopic compositions, or different fluid flow rates are connected by positive-sloped isochronous lines. These isochrons reproduce the effects observed in hydrothermally exchanged mineral pairs including 1) steep positive slopes, 2) common reversals in the measured fractionation factors (??), and 3) measured fractionations that are highly variable over short distances where no thermal gradient can be geologically demonstrated. ?? 1987.

Performance evaluation of cryogenic counter-flow heat exchangers with longitudinal conduction, heat in-leak and property variations

NASA Astrophysics Data System (ADS)

Jiang, Q. F.; Zhuang, M.; Zhu, Z. G.; Y Zhang, Q.; Sheng, L. H.

2017-12-01

Counter-flow plate-fin heat exchangers are commonly utilized in cryogenic applications due to their high effectiveness and compact size. For cryogenic heat exchangers in helium liquefaction/refrigeration systems, conventional design theory is no longer applicable and they are usually sensitive to longitudinal heat conduction, heat in-leak from surroundings and variable fluid properties. Governing equations based on distributed parameter method are developed to evaluate performance deterioration caused by these effects. The numerical model could also be applied in many other recuperators with different structures and, hence, available experimental data are used to validate it. For a specific case of the multi-stream heat exchanger in the EAST helium refrigerator, quantitative effects of these heat losses are further discussed, in comparison with design results obtained by the common commercial software. The numerical model could be useful to evaluate and rate the heat exchanger performance under the actual cryogenic environment.

Negative exchange interactions in coupled few-electron quantum dots

NASA Astrophysics Data System (ADS)

Deng, Kuangyin; Calderon-Vargas, F. A.; Mayhall, Nicholas J.; Barnes, Edwin

2018-06-01

It has been experimentally shown that negative exchange interactions can arise in a linear three-dot system when a two-electron double quantum dot is exchange coupled to a larger quantum dot containing on the order of one hundred electrons. The origin of this negative exchange can be traced to the larger quantum dot exhibiting a spin tripletlike rather than singletlike ground state. Here we show using a microscopic model based on the configuration interaction (CI) method that both tripletlike and singletlike ground states are realized depending on the number of electrons. In the case of only four electrons, a full CI calculation reveals that tripletlike ground states occur for sufficiently large dots. These results hold for symmetric and asymmetric quantum dots in both Si and GaAs, showing that negative exchange interactions are robust in few-electron double quantum dots and do not require large numbers of electrons.

FUEL ROD CLUSTERS

DOEpatents

Schultz, A.B.

1959-08-01

A cluster of nuclear fuel rods and a tubular casing therefor through which a coolant flows in heat-exchange contact with the fuel rods is described. The fuel rcds are held in the casing by virtue of the compressive force exerted between longitudinal ribs of the fuel rcds and internal ribs of the casing or the internal surfaces thereof.

Measurement of spin-lattice relaxation times and concentrations in systems with chemical exchange using the one-pulse sequence: breakdown of the Ernst model for partial saturation in nuclear magnetic resonance spectroscopy.

PubMed

Spencer, R G; Fishbein, K W

2000-01-01

A fundamental problem in Fourier transform NMR spectroscopy is the calculation of observed resonance amplitudes for a repetitively pulsed sample, as first analyzed by Ernst and Anderson in 1966. Applications include determination of spin-lattice relaxation times (T(1)'s) by progressive saturation and correction for partial saturation in order to determine the concentrations of the chemical constituents of a spectrum. Accordingly, the Ernst and Anderson formalism has been used in innumerable studies of chemical and, more recently, physiological systems. However, that formalism implicitly assumes that no chemical exchange occurs. Here, we present an analysis of N sites in an arbitrary chemical exchange network, explicitly focusing on the intermediate exchange rate regime in which the spin-lattice relaxation rates and the chemical exchange rates are comparable in magnitude. As a special case of particular importance, detailed results are provided for a system with three sites undergoing mutual exchange. Specific properties of the N-site network are then detailed. We find that (i) the Ernst and Anderson analysis describing the response of a system to repetitive pulsing is inapplicable to systems with chemical exchange and can result in large errors in T(1) and concentration measurements; (ii) T(1)'s for systems with arbitrary exchange networks may still be correctly determined from a one-pulse experiment using the Ernst formula, provided that a short interpulse delay time and a large flip angle are used; (iii) chemical concentrations for exchanging systems may be correctly determined from a one-pulse experiment either by using a short interpulse delay time with a large flip angle, as for measuring T(1)'s, and correcting for partial saturation by use of the Ernst formula, or directly by using a long interpulse delay time to avoid saturation; (iv) there is a significant signal-to-noise penalty for performing one-pulse experiments under conditions which permit accurate measurements of T(1)'s and chemical concentrations. The present results are analogous to but are much more general than those that we have previously derived for systems with two exchanging sites. These considerations have implications for the design and interpretation of one-pulse experiments for all systems exhibiting chemical exchange in the intermediate exchange regime, including virtually all physiologic samples.

Seasonal soil VOC exchange rates in a Mediterranean holm oak forest and their responses to drought conditions

NASA Astrophysics Data System (ADS)

Asensio, Dolores; Peñuelas, Josep; Ogaya, Romà; Llusià, Joan

Available information on soil volatile organic compound (VOC) exchange, emissions and uptake, is very scarce. We here describe the amounts and seasonality of soil VOC exchange during a year in a natural Mediterranean holm oak forest growing in Southern Catalonia. We investigated changes in soil VOC dynamics in drought conditions by decreasing the soil moisture to 30% of ambient conditions by artificially excluding rainfall and water runoff, and predicted the response of VOC exchange to the drought forecasted in the Mediterranean region for the next decades by GCM and ecophysiological models. The annual average of the total (detected) soil VOC and total monoterpene exchange rates were 3.2±3.2 and -0.4±0.3 μg m -2 h -1, respectively, in control plots. These values represent 0.003% of the total C emitted by soil at the study site as CO 2 whereas the annual mean of soil monoterpene exchange represents 0.0004% of total C. Total soil VOC exchange rates in control plots showed seasonal variations following changes in soil moisture and phenology. Maximum values were found in spring (17±8 μg m -2 h -1). Although there was no significant global effect of drought treatment on the total soil VOC exchange rates, annual average of total VOC exchange rates in drought plots resulted in an uptake rate (-0.5±1.8 μg m -2 h -1) instead of positive net emission rates. Larger soil VOC and monoterpene exchanges were measured in drought plots than in control plots in summer, which might be mostly attributable to autotrophic (roots) metabolism. The results show that the diversity and magnitude of monoterpene and VOC soil emissions are low compared with plant emissions, that they are driven by soil moisture, that they represent a very small part of the soil-released carbon and that they may be strongly reduced or even reversed into net uptakes by the predicted decreases of soil water availability in the next decades. In all cases, it seems that VOC fluxes in soil might have greater impact on soil ecology than on atmospheric chemistry.

Cooperative endeavors: A case study of success

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baker, J.

1997-12-31

Partnerships and cooperative agreements abound in the environmental arena today. This paper briefly highlights the collaborative approach used by the International Cooperative for Ozone Layer Protection (ICOLP). ICOLP has helped international members and non-members to eliminate most of the ozone-depleting solvents from manufacturing processes through the exchange of technical information in a non-proprietary manner. By using alternatives, companies and governments have realized savings in the multiple millions of dollars. Advantages of participating in cooperative environmental partnerships may include: (1) improved access and exchange of information, (2) cost minimization, (3) promotion and facilitation of business opportunities, (4) improved dialogue between groups,more » (5) coordinated approach to complex issues, and (6) technology development and transfer opportunities.« less

Heat and moisture exchanger use reduces in-hospital complications following total laryngectomy: a case-control study.

PubMed

Foreman, A; De Santis, R J; Sultanov, F; Enepekides, D J; Higgins, K M

2016-07-07

Total laryngectomy (TL) is an appropriate oncologic operation for many patients with laryngeal cancer delivering excellent oncologic outcomes, however it remains beset with significant functional consequences. Following TL, the upper and lower airways are permanently disconnected, which causes unfiltered, cold air with reduced humidity to enter the tracheobronchial tree, resulting in mucus overproduction and an increase in the viscosity of the mucus. In response to this, Heat and moisture exchangers were developed to compensate for the lost functions of the upper respiratory tract and their effect on the patients' respiratory performance in addition to their quality of life. The case records of 48 patients undergoing total laryngectomy were reviewed and data concerning demographics, surgical details, post-operative care requirements and adverse events was retrieved. Post hoc analysis of the case patients was undertaken to identify any benefit of using a heat and moisture exchanger (HME) system with particular reference to post-operative respiratory outcomes. There was no significant difference between case and control subjects based on demographics, extent of surgery or need for flap repair. 16 patients had used a HME and 32 patients had used external humidification (EH). Of those experiencing mucous plugging, only 3/24 (12.5 %) had used a HME system, in contrast to 21/24 (87.5 %) who used EH (Chi square = 9.375, p = 0.002). The odds ratio of having an adverse event if not using HME was 8.27 (CI = 1.94 - 35.71). Use of HME also significantly reduced the number of days requiring physiotherapy (1.75 days vs. 3.20 days, p = 0.034). Use of an HME system can reduce in-hospital complications, in particular episodes of mucus plugging, and post-operative care requirements. Furthermore, there is a cost benefit to using HME systems that warrants more widespread introduction of these devices in head and neck surgery centers.

INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY: Competition Between Self-birth and Catalyzed Death in Aggregation Growth with Catalysis Injection

NASA Astrophysics Data System (ADS)

Chen, Dan; Lin, Zhen-Quan; Sun, Yun-Fei; Ke, Jian-Hong

2009-12-01

We propose two irreversible aggregation growth models of aggregates of two distinct species (A and B) to study the interactions between virus aggregates and medicine efficacy aggregates in the virus-medicine cooperative evolution system. The A-species aggregates evolve driven by self monomer birth and B-species aggregate-catalyzed monomer death in model I and by self birth, catalyzed death, and self monomer exchange reactions in model II, while the catalyst B-species aggregates are assumed to be injected into the system sustainedly or at a periodic time-dependent rate. The kinetic behaviors of the A-species aggregates are investigated by the rate equation approach based on the mean-field theory with the self birth rate kernel IA(k) = Ik, catalyzed death rate kernel JAB(k) = Jk and self exchange rate kernel KA (k, l) = Kkl. The kinetic behaviors of the A-species aggregates are mainly dominated by the competition between the two effects of the self birth (with the effective rate I) and the catalyzed death (with the effective rate JB0), while the effects of the self exchanges of the A-species aggregates which appear in an effective rate KA0 play important roles in the cases of I > JB0 and I = JB0. The evolution behaviors of the total mass MA1(t) and the total aggregate number MA0 (t) are obtained, and the aggregate size distribution αk (t) of species A is found to approach a generalized scaling form in the case of I >= JB0 and a special modified scaling form in the case of I < JB0. The periodical evolution of the B-monomers concentration plays an exponential form of the periodic modulation.

A porous flow approach to model thermal non-equilibrium applicable to melt migration

NASA Astrophysics Data System (ADS)

Schmeling, Harro; Marquart, Gabriele; Grebe, Michael

2018-01-01

We develop an approach for heat exchange between a fluid and a solid phase of a porous medium where the temperatures of the fluid and matrix are not in thermal equilibrium. The formulation considers moving of the fluid within a resting or deforming porous matrix in an Eulerian coordinate system. The approach can be applied, for example, to partially molten systems or to brine transport in porous rocks. We start from an existing theory for heat exchange where the energy conservation equations for the fluid and the solid phases are separated and coupled by a heat exchange term. This term is extended to account for the full history of heat exchange. It depends on the microscopic geometry of the fluid phase. For the case of solid containing hot, fluid-filled channels, we derive an expression based on a time-dependent Fourier approach for periodic half-waves. On the macroscopic scale, the temporal evolution of the heat exchange leads to a convolution integral along the flow path of the solid, which simplifies considerably in case of a resting matrix. The evolution of the temperature in both phases with time is derived by inserting the heat exchange term into the energy equations. We explore the effects of thermal non-equilibrium between fluid and solid by considering simple cases with sudden temperature differences between fluid and solid as initial or boundary conditions, and by varying the fluid velocity with respect to the resting porous solid. Our results agree well with an analytical solution for non-moving fluid and solid. The temperature difference between solid and fluid depends on the Peclet number based on the Darcy velocity. For Peclet numbers larger than 1, the temperature difference after one diffusion time reaches 5 per cent of \\tilde{T} or more (\\tilde{T} is a scaling temperature, e.g. the initial temperature difference). Thus, our results imply that thermal non-equilibrium can play an important role for melt migration through partially molten systems where melt focuses into melt channels near the transition to melt ascent by dykes. Our method is based on solving the convolution integration for the heat exchange over the full flow history, which is numerically expensive. We tested to replace the heat exchange term by an instantaneous, approximate term. We found considerable errors on the short timescale, but a good agreement on the long timescale if appropriate parameters for the approximate terms are used. We derived these parameters which may be implemented in fully dynamical two-phase flow formulations of melt migration in the Earth.

Intensification of heat and mass transfer by ultrasound: application to heat exchangers and membrane separation processes.

PubMed

Gondrexon, N; Cheze, L; Jin, Y; Legay, M; Tissot, Q; Hengl, N; Baup, S; Boldo, P; Pignon, F; Talansier, E

2015-07-01

This paper aims to illustrate the interest of ultrasound technology as an efficient technique for both heat and mass transfer intensification. It is demonstrated that the use of ultrasound results in an increase of heat exchanger performances and in a possible fouling monitoring in heat exchangers. Mass transfer intensification was observed in the case of cross-flow ultrafiltration. It is shown that the enhancement of the membrane separation process strongly depends on the physico-chemical properties of the filtered suspensions. Copyright © 2014 Elsevier B.V. All rights reserved.

Multipolar Kondo effect in a S10-P32 mixture of 173Yb atoms

NASA Astrophysics Data System (ADS)

Kuzmenko, Igor; Kuzmenko, Tetyana; Avishai, Yshai; Jo, Gyu-Boong

2018-02-01

Whereas in the familiar Kondo effect the exchange interaction is dipolar, there are systems in which the exchange interaction is multipolar, as has been realized in a recent experiment. Here, we study multipolar Kondo effect in a Fermi gas of cold 173Yb atoms. Making use of different ac polarizabilities of the electronic ground state Yb (S10 ) and the long-lived metastable state Yb*(P32 ), it is suggested that the latter atoms can be localized and serve as a dilute concentration of magnetic impurities while the former ones remain itinerant. The exchange mechanism between the itinerant Yb and the localized Yb* atoms is analyzed and shown to be antiferromagnetic. The quadrupole and octupole interactions act to enhance the Kondo temperature TK that is found to be experimentally accessible. The bare exchange Hamiltonian needs to be decomposed into dipole (d), quadrupole (q), and octupole (o) interactions in order to retain its form under renormalization group (RG) analysis, in which the corresponding exchange constants (λd,λq, and λo) flow independently. Numerical solution of the RG scaling equations reveals a few finite fixed points. Arguments are presented that the Fermi-liquid fixed point at low temperature is unstable, indicating that the impurity is overscreened, which suggests a non-Fermi-liquid phase. The impurity contributions to the specific heat, entropy, and the magnetic susceptibility are calculated in the weak coupling regime (T ≫TK ), and are compared with the analogous results obtained for the standard case of dipolar exchange interaction (the s -d Hamiltonian).

Immunoglobulin for alloimmune hemolytic disease in neonates.

PubMed

Zwiers, Carolien; Scheffer-Rath, Mirjam Ea; Lopriore, Enrico; de Haas, Masja; Liley, Helen G

2018-03-18

Exchange transfusion and phototherapy have traditionally been used to treat jaundice and avoid the associated neurological complications. Because of the risks and burdens of exchange transfusion, intravenous immunoglobulin (IVIg) has been suggested as an alternative therapy for alloimmune hemolytic disease of the newborn (HDN) to reduce the need for exchange transfusion. To assess the effect and complications of IVIg in newborn infants with alloimmune HDN on the need for and number of exchange transfusions. We performed electronic searches of CENTRAL, PubMed, Embase (Ovid), Web of Science, CINAHL (EBSCOhost), Academic Search Premier, and the trial registers ClinicalTrials.gov and controlled-trials.com in May 2017. We also searched reference lists of included and excluded trials and relevant reviews for further relevant studies. We considered all randomized and quasi-randomized controlled trials of IVIg in the treatment of alloimmune HDN. Trials must have used predefined criteria for the use of IVIg and exchange transfusion therapy to be included. We used the standard methods of Cochrane and its Neonatal Review Group. We assessed studies for inclusion and two review authors independently assessed quality and extracted data. We discussed any differences of opinion to reach consensus. We contacted investigators for additional or missing information. We calculated risk ratio (RR), risk difference (RD) and number needed to treat for an additional beneficial outcome (NNTB) for categorical outcomes. We calculated mean difference (MD) for continuous variables. We used GRADE criteria to assess the risk of bias for major outcomes and to summarize the level of evidence. Nine studies with 658 infants fulfilled the inclusion criteria. Term and preterm infants with Rh or ABO (or both) incompatibility were included. The use of exchange transfusion decreased significantly in the immunoglobulin treated group (typical RR 0.35, 95% CI 0.25 to 0.49; typical RD -0.22, 95% CI -0.27 to -0.16; NNTB 5). The mean number of exchange transfusions per infant was also significantly lower in the immunoglobulin treated group (MD -0.34, 95% CI -0.50 to -0.17). However, sensitivity analysis by risk of bias showed that in the only two studies in which the treatment was masked by use of a placebo and outcome assessment was blinded, the results differed; there was no difference in the need for exchange transfusions (RR 0.98, 95% CI 0.48 to 1.98) or number of exchange transfusions (MD -0.04, 95% CI -0.18 to 0.10). Two studies assessed long-term outcomes and found no cases of kernicterus, deafness or cerebral palsy. Although overall results show a significant reduction in the need for exchange transfusion in infants treated with IVIg, the applicability of the results is limited because of low to very low quality of evidence. Furthermore, the two studies at lowest risk of bias show no benefit of IVIg in reducing the need for and number of exchange transfusions. Based on these results, we have insufficient confidence in the effect estimate for benefit of IVIg to make even a weak recommendation for the use of IVIg for the treatment of alloimmune HDN. Further studies are needed before the use of IVIg for the treatment of alloimmune HDN can be recommended, and should include blinding of the intervention by use of a placebo as well as sufficient sample size to assess the potential for serious adverse effects.

Water exchange, mixing and transient storage between a saturated karstic conduit and the surrounding aquifer: Groundwater flow modeling and inputs from stable water isotopes

NASA Astrophysics Data System (ADS)

Binet, S.; Joigneaux, E.; Pauwels, H.; Albéric, P.; Fléhoc, Ch.; Bruand, A.

2017-01-01

Water exchanges between a karstic conduit and the surrounding aquifer are driven by hydraulic head gradient at the interface between these two domains. The case-study presented in this paper investigates the impact of the geometry and interface conditions around a conduit on the spatial distribution of these exchanges. Isotopic (δ18O and δD), discharge and water head measurements were conducted at the resurgences of a karst system with a strong allogenic recharge component (Val d'Orléans, France), to estimate the amounts of water exchanged and the mixings between a saturated karstic conduit and the surrounding aquifer. The spatio-temporal variability of the observed exchanges was explored using a 2D coupled continuum-conduit flow model under saturated conditions (Feflow®). The inputs from the water heads and stable water isotopes in the groundwater flow model suggest that the amounts of water flowing from the aquifer are significant if the conduit flow discharges are less than the conduit flow capacity. This condition creates a spatial distribution of exchanges from upstream where the aquifer feeds the conduit (recharge area) to downstream where the conduit reaches its maximum discharge capacity and can feed the aquifer (discharge area). In the intermediate transport zone no exchange between the two domains takes place that brings a new criterion to delineate the vulnerable zones to surface water. On average, 4% of the water comes from the local recharge, 80% is recent river water and 16% is old river water. During the November 2008 flood, both isotopic signatures and model suggest that exchanges fluctuate around this steady state, limited when the river water level increases and intensified when the river water level decreases. The existence of old water from the river suggests a transient storage at the aquifer/conduit interface that can be considered as an underground hyporheic zone.

Multicenter comparative trial of the V-scope system for therapeutic ERCP.

PubMed

Joyce, A M; Ahmad, N A; Beilstein, M C; Kochman, M L; Long, W B; Baron, T; Sherman, S; Fogel, E; Lehman, G A; McHenry, L; Watkins, J; Ginsberg, G G

2006-07-01

A new duodenoscope (the V-scope), with a modified elevator used in combination with a dedicated short guide wire, constitutes the V-system. This system is intended to allow fixation of the guide wire at the elevator lever, thereby enhancing the speed and reliability of accessory exchange over a guide wire during ERCP. The aim of this study was to evaluate the extent to which the V-system provides improved efficiency in comparison with conventional duodenoscope and guide wire combinations. This was an industry-sponsored multicenter randomized trial. Patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) procedures in which treatment was anticipated were randomly assigned to the V-system or to a conventional duodenoscope and accessories used routinely in each center. The parameters recorded included the total case time, fluoroscopy time, catheter/guide wire exchange time, guide wire repositioning, loss of guide wire access, and success or failure of guide wire fixation when using the V-system. Fifty patients were included, 22 in the conventional group and 28 in the V-system group. A total of 135 exchanges were carried out. The patients had up to six exchanges. The median exchange time was 19.4 s with the V-system and 31.7 s with the conventional systems ( P < 0.001). Guide wire repositioning was required less often in the V-system group ( P = 0.0005). The V-system effectively locked the guide wire in 63 of 71 exchanges (89 %). Loss of guide wire access occurred in two patients in the conventional group and four in the V-system group, attributable to failure to lock the guide wire early during the experience (no significant differences). The V-system can effectively secure the guide wire during accessory exchange in ERCP and reduces the time required to exchange accessories. This may enhance overall efficiency during ERCP.

The Significance of Harm Reduction as a Social and Health Care Intervention for Injecting Drug Users: An Exploratory Study of a Needle Exchange Program in Fresno, California.

PubMed

Clarke, Kris; Harris, Debra; Zweifler, John A; Lasher, Marc; Mortimer, Roger B; Hughes, Susan

2016-01-01

Infectious disease remains a significant social and health concern in the United States. Preventing more people from contracting HIV/AIDS or Hepatitis C (HCV), requires a complex understanding of the interconnection between the biomedical and social dimensions of infectious disease. Opiate addiction in the US has skyrocketed in recent years. Preventing more cases of HIV/AIDS and HCV will require dealing with the social determinants of health. Needle exchange programs (NEPs) are based on a harm reduction approach that seeks to minimize the risk of infection and damage to the user and community. This article presents an exploratory small-scale quantitative study of the injection drug using habits of a group of injection drug users (IDUs) at a needle exchange program in Fresno, California. Respondents reported significant decreases in high risk IDU behaviors, including sharing of needles and to a lesser extent re-using of needles. They also reported frequent use of clean paraphernalia. Greater collaboration between social and health outreach professionals at NEPs could provide important frontline assistance to people excluded from mainstream office-based services and enhance efforts to reduce HIV/AIDS or HCV infection.

Investigating Block-Copolymer Micelle Dynamics for Tunable Cargo Delivery

NASA Astrophysics Data System (ADS)

Li, Xiuli; Kidd, Bryce; Cooksey, Tyler; Robertson, Megan; Madsen, Louis

Block-copolymer micelles (BCPMs) can carry molecular cargo in a nanoscopic package that is tunable using polymer structure in combination with cargo properties, as well as with external stimuli such as temperature or pH. For example, BCPMs can be used in targeted anticancer drug delivery due to their biocompatibility, in vivo degradability and prolonged circulation time. We are using NMR spectroscopy and diffusometry as well as SANS to investigate BCPMs. Here we study a diblock poly(ethylene oxide)-b-(caprolactone) (PEO-PCL) that forms spherical micelles at 1% (w/v) in the mixed solvent D2O/THF-d8. We quantify the populations and diffusion coefficients of coexisting micelles and free unimers over a range of temperatures and solvent compositions. We use temperature as a stimulus to enhance unimer exchange and hence trigger cargo release, in some cases at a few degrees above body temperature. We present evidence for dominance of the insertion-expulsion mechanism of unimer exchange in these systems, and we map phase diagrams versus temperature and solvent composition. This study sheds light on how intermolecular interactions fundamentally affect cargo release, unimer exchange, and overall micelle tunability.

Workshop report: Identifying opportunities for global integration of toxicogenomics databases, 26-27 June 2013, Research Triangle Park, NC, USA.

PubMed

Hendrickx, Diana M; Boyles, Rebecca R; Kleinjans, Jos C S; Dearry, Allen

2014-12-01

A joint US-EU workshop on enhancing data sharing and exchange in toxicogenomics was held at the National Institute for Environmental Health Sciences. Currently, efficient reuse of data is hampered by problems related to public data availability, data quality, database interoperability (the ability to exchange information), standardization and sustainability. At the workshop, experts from universities and research institutes presented databases, studies, organizations and tools that attempt to deal with these problems. Furthermore, a case study showing that combining toxicogenomics data from multiple resources leads to more accurate predictions in risk assessment was presented. All participants agreed that there is a need for a web portal describing the diverse, heterogeneous data resources relevant for toxicogenomics research. Furthermore, there was agreement that linking more data resources would improve toxicogenomics data analysis. To outline a roadmap to enhance interoperability between data resources, the participants recommend collecting user stories from the toxicogenomics research community on barriers in data sharing and exchange currently hampering answering to certain research questions. These user stories may guide the prioritization of steps to be taken for enhancing integration of toxicogenomics databases.

Neural-network Kohn-Sham exchange-correlation potential and its out-of-training transferability

NASA Astrophysics Data System (ADS)

Nagai, Ryo; Akashi, Ryosuke; Sasaki, Shu; Tsuneyuki, Shinji

2018-06-01

We incorporate in the Kohn-Sham self-consistent equation a trained neural-network projection from the charge density distribution to the Hartree-exchange-correlation potential n → VHxc for a possible numerical approach to the exact Kohn-Sham scheme. The potential trained through a newly developed scheme enables us to evaluate the total energy without explicitly treating the formula of the exchange-correlation energy. With a case study of a simple model, we show that the well-trained neural-network VHxc achieves accuracy for the charge density and total energy out of the model parameter range used for the training, indicating that the property of the elusive ideal functional form of VHxc can approximately be encapsulated by the machine-learning construction. We also exemplify a factor that crucially limits the transferability—the boundary in the model parameter space where the number of the one-particle bound states changes—and see that this is cured by setting the training parameter range across that boundary. The training scheme and insights from the model study apply to more general systems, opening a novel path to numerically efficient Kohn-Sham potential.

Corrosion susceptibility of steel drums to be used as containers for intermediate level nuclear waste

NASA Astrophysics Data System (ADS)

Farina, S.; Schulz Rodriguez, F.; Duffó, G.

2013-07-01

The present work is a study of the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins contaminated with different types and concentrations of aggressive species. A special type of specimen was manufactured to simulate the cemented ion-exchange resins in the drum. The evolution of the corrosion potential and the corrosion rate of the steel, as well as the electrical resistivity of the matrix were monitored over a time period of 900 days. The aggressive species studied were chloride ions (the main ionic species of concern) and sulphate ions (produced during radiolysis of the cationic exchange-resins after cementation). The work was complemented with an analysis of the corrosion products formed on the steel in each condition, as well as the morphology of the corrosion products. When applying the results obtained in the present work to estimate the corrosion depth of the steel drumscontaining the cemented radioactive waste after a period of 300 years (foreseen durability of the Intermediate Level Radioactive Waste facility in Argentina) , it is found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums.

Low-temperature, non-stoichiometric oxygen isotope exchange coupled to Fe(II)-goethite interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frierdich, Andrew J.; Beard, Brian L.; Rosso, Kevin M.

2015-07-01

The oxygen isotope composition of natural iron oxide minerals has been widely used as a paleoclimate proxy. Interpretation of their stable isotope compositions, however, requires accurate knowledge of isotopic fractionation factors and an understanding of their isotopic exchange kinetics, the latter of which informs us how diagenetic processes may alter their isotopic compositions. Prior work has demonstrated that crystalline iron oxides do not significantly exchange oxygen isotopes with pure water at low temperature, which has restricted studies of isotopic fractionation factors to precipitation experiments or theoretical calculations. Using a double three-isotope method (¹⁸O-¹⁷O-¹⁶O and ⁵⁷Fe-⁵⁶Fe-⁵⁴Fe) we compare O and Femore » isotope exchange kinetics, and demonstrate, for the first time, that O isotope exchange between structural O in crystalline goethite and water occurs in the presence of aqueous Fe(II) (Fe(II) aq) at ambient temperature (i.e., 22–50 °C). The three-isotope method was used to extrapolate partial exchange results to infer the equilibrium, mass-dependent isotope fractionations between goethite and water. In addition, this was combined with a reversal approach to equilibrium by reacting goethite in two unique waters that vary in composition by about 16‰ in ¹⁸O/¹⁶O ratios. Our results show that interactions between Fe(II) aq and goethite catalyzes O isotope exchange between the mineral and bulk fluid; no exchange (within error) is observed when goethite is suspended in ¹⁷O-enriched water in the absence of Fe(II) aq. In contrast, Fe(II)-catalyzed O isotope exchange is accompanied by significant changes in ¹⁸O/¹⁶O ratios. Despite significant O exchange, however, we observed disproportionate amounts of Fe versus O exchange, where Fe isotope exchange in goethite was roughly three times that of O. This disparity provides novel insight into the reactivity of oxide minerals in aqueous solutions, but presents a challenge for utilizing such an approach to determine equilibrium isotope fractionation factors. Despite the uncertainty from extrapolation, there is consistency in goethite-water fractionation factors for our reversal approach to equilibrium, with final weighted average fractionation factor values of Δ¹⁸O Gth-wate r = 0.2 (±0.9‰) and 3.0 (±2.5‰) at 22 °C and -1.6 (±0.8‰) and 1.9 (±1.5‰) at 50 °C for micron-sized and nano-particulate goethite, respectively (errors at 2σ level). Reaction of ferrihydrite with Fe(II) aq in two distinct waters resulted in a quantitative conversion to goethite and complete O isotope exchange in each case, and similar fractionation factors were observed for experiments using the two waters. Comparison of our results with previous studies of O isotope fractionation between goethite and water suggests that particle size may be a contributing factor to the disparity among experimental studies.« less

The TULIP superfamily of eukaryotic lipid-binding proteins as a mediator of lipid sensing and transport.

PubMed

Alva, Vikram; Lupas, Andrei N

2016-08-01

The tubular lipid-binding (TULIP) superfamily has emerged in recent years as a major mediator of lipid sensing and transport in eukaryotes. It currently encompasses three protein families, SMP-like, BPI-like, and Takeout-like, which share a common fold. This fold consists of a long helix wrapped in a highly curved anti-parallel β-sheet, enclosing a central, lipophilic cavity. The SMP-like proteins, which include subunits of the ERMES complex and the extended synaptotagmins (E-Syts), appear to be mainly located at membrane contacts sites (MCSs) between organelles, mediating inter-organelle lipid exchange. The BPI-like proteins, which include the bactericidal/permeability-increasing protein (BPI), the LPS (lipopolysaccharide)-binding protein (LBP), the cholesteryl ester transfer protein (CETP), and the phospholipid transfer protein (PLTP), are either involved in innate immunity against bacteria through their ability to sense lipopolysaccharides, as is the case for BPI and LBP, or in lipid exchange between lipoprotein particles, as is the case for CETP and PLTP. The Takeout-like proteins, which are comprised of insect juvenile hormone-binding proteins and arthropod allergens, transport, where known, lipid hormones to target tissues during insect development. In all cases, the activity of these proteins is underpinned by their ability to bind large, hydrophobic ligands in their central cavity and segregate them away from the aqueous environment. Furthermore, where they are involved in lipid exchange, recent structural studies have highlighted their ability to establish lipophilic, tubular channels, either between organelles in the case of SMP domains or between lipoprotein particles in the case of CETP. Here, we review the current knowledge on the structure, versatile functions, and evolution of the TULIP superfamily. We propose a deep evolutionary split in this superfamily, predating the Last Eukaryotic Common Ancestor, between the SMP-like proteins, which act on lipids endogenous to the cell, and the BPI-like proteins (including the Takeout-like proteins of arthropods), which act on exogenous lipids. This article is part of a Special Issue entitled: The cellular lipid landscape edited by Tim P. Levine and Anant K. Menon. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterizing multiple timescales of stream and storage zone interaction that affect solute fate and transport in streams

USGS Publications Warehouse

Choi, Jungyill; Harvey, Judson W.; Conklin, Martha H.

2000-01-01

The fate of contaminants in streams and rivers is affected by exchange and biogeochemical transformation in slowly moving or stagnant flow zones that interact with rapid flow in the main channel. In a typical stream, there are multiple types of slowly moving flow zones in which exchange and transformation occur, such as stagnant or recirculating surface water as well as subsurface hyporheic zones. However, most investigators use transport models with just a single storage zone in their modeling studies, which assumes that the effects of multiple storage zones can be lumped together. Our study addressed the following question: Can a single‐storage zone model reliably characterize the effects of physical retention and biogeochemical reactions in multiple storage zones? We extended an existing stream transport model with a single storage zone to include a second storage zone. With the extended model we generated 500 data sets representing transport of nonreactive and reactive solutes in stream systems that have two different types of storage zones with variable hydrologic conditions. The one storage zone model was tested by optimizing the lumped storage parameters to achieve a best fit for each of the generated data sets. Multiple storage processes were categorized as possessing I, additive; II, competitive; or III, dominant storage zone characteristics. The classification was based on the goodness of fit of generated data sets, the degree of similarity in mean retention time of the two storage zones, and the relative distributions of exchange flux and storage capacity between the two storage zones. For most cases (>90%) the one storage zone model described either the effect of the sum of multiple storage processes (category I) or the dominant storage process (category III). Failure of the one storage zone model occurred mainly for category II, that is, when one of the storage zones had a much longer mean retention time (ts ratio > 5.0) and when the dominance of storage capacity and exchange flux occurred in different storage zones. We also used the one storage zone model to estimate a “single” lumped rate constant representing the net removal of a solute by biogeochemical reactions in multiple storage zones. For most cases the lumped rate constant that was optimized by one storage zone modeling estimated the flux‐weighted rate constant for multiple storage zones. Our results explain how the relative hydrologic properties of multiple storage zones (retention time, storage capacity, exchange flux, and biogeochemical reaction rate constant) affect the reliability of lumped parameters determined by a one storage zone transport model. We conclude that stream transport models with a single storage compartment will in most cases reliably characterize the dominant physical processes of solute retention and biogeochemical reactions in streams with multiple storage zones.

Random isotropic one-dimensional XY-model

NASA Astrophysics Data System (ADS)

Gonçalves, L. L.; Vieira, A. P.

1998-01-01

The 1D isotropic s = ½XY-model ( N sites), with random exchange interaction in a transverse random field is considered. The random variables satisfy bimodal quenched distributions. The solution is obtained by using the Jordan-Wigner fermionization and a canonical transformation, reducing the problem to diagonalizing an N × N matrix, corresponding to a system of N noninteracting fermions. The calculations are performed numerically for N = 1000, and the field-induced magnetization at T = 0 is obtained by averaging the results for the different samples. For the dilute case, in the uniform field limit, the magnetization exhibits various discontinuities, which are the consequence of the existence of disconnected finite clusters distributed along the chain. Also in this limit, for finite exchange constants J A and J B, as the probability of J A varies from one to zero, the saturation field is seen to vary from Γ A to Γ B, where Γ A(Γ B) is the value of the saturation field for the pure case with exchange constant equal to J A(J B) .

[Use of the air-Q laryngeal airway and tube exchanger in a case of difficult tracheal extubation after maxillectomy].

PubMed

Komasawa, Nobuyasu; Ueki, Ryusuke; Iwasaki, Yohei; Tatara, Tsuneo; Tashiro, Chikara; Kaminoh, Yoshiroh

2012-10-01

A 79-year-old man was diagnosed with maxillary cancer and underwent total maxillectomy under general anesthesia. The oropharyngeal airway was needed for efficient mask ventilation during anesthesia induction. The maxilla was totally resected and reconstructed with skin from a femoral flap. Tracheal extubation was considered to be difficult given that mask ventilation was contraindicated due to reconstruction of the maxilla. After inserting a tube exchanger (TE) into the trachea, the tracheal tube was exchanged with an air-Q laryngeal airway through the TE. After confirming effective ventilation with the air-Q mask, the patient was awakened from anesthesia. We confirmed sufficient spontaneous breathing and no active bleeding in the pharynx. After re-inserting the TE thorough air-Q, the air-Q was removed, followed by removal of the TE. These findings suggest that the air-Q and TE were effective in a case of difficult extubation after maxillectomy.

Occupational health crossing borders - part 1: concept, teaching methods, and user evaluation of the first international summer school in Munich, Germany.

PubMed

Radon, Katja; Ehrenstein, Vera; Bigaignon-Cantineau, Janine; Vellore, Arun Dev; Fingerhut, Marilyn; Nowak, Dennis

2009-10-01

Occupational health and safety (OHS) is relevant for occupational health professionals (OHP) throughout the world. However, training opportunities are often limited and exchange between OHP from industrialized and developing countries is sparse. We aimed to contribute to the international exchange of OHP through a 2-week summer school program. Twenty-three OHP from 11 countries participated. Teaching methods included interactive lectures, participants' presentations, case-based e-learning, enterprise visits, and hands-on sessions. After completion, participants evaluated the course. OHS systems of 18 different countries were presented using the same set of clinical cases as a starting point. Opportunities and challenges in the different OHS systems were considered. On median, participants rated the course as excellent and totally agreed that it will help them in their daily work. An international summer school teaching basic aspects of different OHS systems is a useful tool for training and exchange at the global level. Copyright 2009 Wiley-Liss, Inc.

Quantitative Analysis of Guanine Nucleotide Exchange Factors (GEFs) as Enzymes

PubMed Central

Randazzo, Paul A; Jian, Xiaoying; Chen, Pei-Wen; Zhai, Peng; Soubias, Olivier; Northup, John K

2014-01-01

The proteins that possess guanine nucleotide exchange factor (GEF) activity, which include about ~800 G protein coupled receptors (GPCRs),1 15 Arf GEFs,2 81 Rho GEFs,3 8 Ras GEFs,4 and others for other families of GTPases,5 catalyze the exchange of GTP for GDP on all regulatory guanine nucleotide binding proteins. Despite their importance as catalysts, relatively few exchange factors (we are aware of only eight for ras superfamily members) have been rigorously characterized kinetically.5–13 In some cases, kinetic analysis has been simplistic leading to erroneous conclusions about mechanism (as discussed in a recent review14). In this paper, we compare two approaches for determining the kinetic properties of exchange factors: (i) examining individual equilibria, and; (ii) analyzing the exchange factors as enzymes. Each approach, when thoughtfully used,14,15 provides important mechanistic information about the exchange factors. The analysis as enzymes is described in further detail. With the focus on the production of the biologically relevant guanine nucleotide binding protein complexed with GTP (G•GTP), we believe it is conceptually simpler to connect the kinetic properties to cellular effects. Further, the experiments are often more tractable than those used to analyze the equilibrium system and, therefore, more widely accessible to scientists interested in the function of exchange factors. PMID:25332840

Multi-layer membrane model for mass transport in a direct ethanol fuel cell using an alkaline anion exchange membrane

NASA Astrophysics Data System (ADS)

Bahrami, Hafez; Faghri, Amir

2012-11-01

A one-dimensional, isothermal, single-phase model is presented to investigate the mass transport in a direct ethanol fuel cell incorporating an alkaline anion exchange membrane. The electrochemistry is analytically solved and the closed-form solution is provided for two limiting cases assuming Tafel expressions for both oxygen reduction and ethanol oxidation. A multi-layer membrane model is proposed to properly account for the diffusive and electroosmotic transport of ethanol through the membrane. The fundamental differences in fuel crossover for positive and negative electroosmotic drag coefficients are discussed. It is found that ethanol crossover is significantly reduced upon using an alkaline anion exchange membrane instead of a proton exchange membrane, especially at current densities higher than 500 A m

Ion exchangers in radioactive waste management: natural Iranian zeolites.

PubMed

Nilchi, A; Maalek, B; Khanchi, A; Ghanadi Maragheh, M; Bagheri, A; Savoji, K

2006-01-01

Five samples of natural zeolites from different parts of Iran were chosen for this study. In order to characterize and determine their structures, X-ray diffraction and infrared spectrometry were carried out for each sample. The selective absorption properties of each zeolite were found by calculating the distribution coefficient (K(d)) of various simulated wastes which were prepared by spiking the radionuclides with (131)I, (99)Mo, (153)Sm, (140)La and (147)Nd. All the zeolite samples used in this study had extremely high absorption value towards (140)La; clinoptolite from Mianeh and analsite from Ghalehkhargoshi showed good absorption for (147)Nd; clinoptolite from Semnan and clinoptolite from Firozkoh showed high absorption for (153)Sm; mesolite from Arababad Tabas showed good absorption for (99)Mo; and finally mesolite from Arababad Tabas, clinoptolite from Semnan and clinoptolite from Firozkoh could be used to selectively absorb (131)I from the stimulated waste which was prepared. The natural zeolites chosen for these studies show a similar pattern to those synthetic ion exchangers in the literature and in some cases an extremely high selectivity towards certain radioactive elements. Hence the binary separation of radioactive elements could easily be carried out. Furthermore, these zeolites, which are naturally occurring ion exchangers, are viable economically and extremely useful alternatives in this industry.

A novel association of acquired ADAMTS13 inhibitor and acute dengue virus infection.

PubMed

Rossi, Fernanda C; Angerami, Rodrigo N; de Paula, Erich V; Orsi, Fernanda L; Shang, Dezhi; del Guercio, Vânia M; Resende, Mariângela R; Annichino-Bizzacchi, Joyce M; da Silva, Luiz J; Zheng, X Long; Castro, Vagner

2010-01-01

Dengue is a mosquito-borne viral disease with an increasing incidence worldwide. Thrombocytopenia is a common finding in dengue virus (DV) infection; however, the underlying mechanisms remain unknown. Here we provide the first evidence of a case of antibody formation against ADAMTS13 (ADAMTS13 inhibitor) in the course of a severe acute DV infection resulting in thrombotic microangiopathy (TMA). The patient presented with classical dengue symptoms (positive epidemiology, high fever, myalgia, predominantly in the lower limbs and lumbar region for 1 week) and, after 11 days of initial symptoms, developed TMA. Clinical and laboratorial investigation of dengue and TMA was performed. The patient presented with ADAMTS13 inhibitor (IgG) during the acute phase of the disease, without anti-platelet antibodies detectable. Dengue infection had laboratorial confirmation. There were excellent clinical and laboratory responses to 11 serial plasma exchanges. Anti-ADAMTS13 inhibitor disappeared after remission of TMA and dengue resolution. No recurrence of TMA symptoms was observed after 2-year follow-up. Although the real incidence of dengue-related TMA is unknown, this case provides the basis for future epidemiologic studies on acquired ADAMTS13 deficiency in DV infection. The prompt clinical recognition of this complication and early installment of specific therapy with plasma exchange are likely to improve the outcome of severe cases of dengue.

Permutation parity machines for neural cryptography.

PubMed

Reyes, Oscar Mauricio; Zimmermann, Karl-Heinz

2010-06-01

Recently, synchronization was proved for permutation parity machines, multilayer feed-forward neural networks proposed as a binary variant of the tree parity machines. This ability was already used in the case of tree parity machines to introduce a key-exchange protocol. In this paper, a protocol based on permutation parity machines is proposed and its performance against common attacks (simple, geometric, majority and genetic) is studied.

The Effect of Raffle Odds on Signing In at a Treatment Center for Adults with Mental Illness

ERIC Educational Resources Information Center

Gravina, Nicole; Wilder, David A.; White, Holly; Fabian, Todd

2005-01-01

This case study describes the use of a daily raffle to increase attendance in a socialization center for approximately 75 adults diagnosed with mental illness. Specifically, the relationship between signing in, which was a measure of attendance, and the odds of winning points which could be exchanged for tangible and edible items was examined. An…

"The Earth is Not Flat Any More": Reflections on the Impact of a Rural/Urban Educational Leadership Exchange on Place-Based Instruction

ERIC Educational Resources Information Center

Norris, Cynthia J.

2005-01-01

This article presents an exploratory case study that sought to gain insight into the development of both cognitive and affective understandings of place that resulted from the UTK (University of Tennessee in Knoxville) cohort visits to the Cincinnati schools. Ten reflections were collected from the cohort members upon their return from these…

XML Technology Assessment

DTIC Science & Technology

2001-01-01

System (GCCS) Track Database Management System (TDBM) (3) GCCS Integrated Imagery and Intelligence (3) Intelligence Shared Data Server (ISDS) General ...The CTH is a powerful model that will allow more than just message systems to exchange information. It could be used for object-oriented databases, as...of the Naval Integrated Tactical Environmental System I (NITES I) is used as a case study to demonstrate the utility of this distributed component

Estimating foundation water vapor release using a simple moisture balance and AIM-2 : case study of a contemporary wood-frame house

Treesearch

C. R. Boardman; Samuel V. Glass; Charles G. Carll

2010-01-01

Proper management of indoor humidity in buildings is an essential aspect of durability. Following dissipation of moisture from construction materials, humidity levels during normal operation are generally assumed to primarily depend on the building volume, the number of building occupants and their behavior, the air exchange rate, and the water vapor content of outdoor...

Writing an Empire: Cross-Talk on Authority, Act, and Relationships with the Other in the "Analects," "Daodejing," and "HanFeizi"

ERIC Educational Resources Information Center

Lyon, Arabella

2010-01-01

The author calls for scholars of rhetoric and composition to become familiar with the cosmology, language, educational attitudes, speech genres, and intellectual debates of a specific culture other than their own. For a case study, she turns to Chinese history and focuses on exchanges between three models of rhetoric: Confucian, Daoist, and…

A Case Study of the NATO Identification System (NIS) Codevelopment Program

DTIC Science & Technology

1988-09-01

the otherhand are unrelated to the military equipment being purchased. These offsets include foreign investment, technology transfer, and countertrade ...manufacturer and a foreign entity. 6. Countertrade - a transaction that specifies the exchange of selected goods and services for another of equivalent...arrangements. In fact, U.S. agencies are permitted to provide advisory and marketing intelligence services to U.S. exporters involved in countertrade

E-Pals: Examining a Cross-Cultural Writing/Literature Project.

ERIC Educational Resources Information Center

McClanahan, Lauren G.

This paper reports on a case study of a U.S. high school literature class during an e-mail exchange with a high school literature class in Moscow (Russia). During this project, the students in both classrooms read short stories by Anton Chekhov and O'Henry. By using the stories as a catalyst, the students' goal was to help their distant partner to…

Concept of an Exchange Network for the Development of Vocational Training in Small and Medium-Sized Enterprises.

ERIC Educational Resources Information Center

Boudet, Rene

An examination of the ways in which vocational training can be extended to small and medium-sized enterprises in the European Economic Community, this document consists of: an introduction; four parts containing multiple chapters; 10 case studies; and a bibliography. Following the introduction, which is an update of a report made in 1985, part one…

Marital Construction of Family Power among Male-out-Migrant Couples in a Chinese Village: A Relation-Oriented Exchange Model

ERIC Educational Resources Information Center

Zuo, Jiping

2008-01-01

This study examines marital construction of family power among male-out-migrant couples in a Chinese village in Guangxi Province. In-depth interviews show that male-out-migrant couples prefer joint decision making. When couples are in disputes, power tends to go to the ones who shoulder greater household-based responsibilities; in this case, they…

Architectural Design Education: Designing a Library, Public Communication and Information Center in the Manufacturing Zone of Central Eskis, Ehir Turkey, a Case Study

ERIC Educational Resources Information Center

Caglar, Nur; Uludag, Zeynep

2006-01-01

It is a fact that architectural design education has become the focus of an extremely complicated set of issues and conscientious debates. Therefore, to extend and challenge educational understanding in architecture it becomes crucial to exchange pedagogical practices. In this article, a specific theoretical approach and teaching methodology,…

Permutation parity machines for neural cryptography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reyes, Oscar Mauricio; Escuela de Ingenieria Electrica, Electronica y Telecomunicaciones, Universidad Industrial de Santander, Bucaramanga; Zimmermann, Karl-Heinz

2010-06-15

Recently, synchronization was proved for permutation parity machines, multilayer feed-forward neural networks proposed as a binary variant of the tree parity machines. This ability was already used in the case of tree parity machines to introduce a key-exchange protocol. In this paper, a protocol based on permutation parity machines is proposed and its performance against common attacks (simple, geometric, majority and genetic) is studied.

"Staying on Our Feet": Novice Music Teachers' Sharing of Emotions and Experiences within an Online Community

ERIC Educational Resources Information Center

Bell-Robertson, Catherine G.

2014-01-01

Multiple forms of support for teachers new to the profession are important and necessary. The use of an online community by 11 novice instrumental music teachers at the middle school and high school levels was investigated in this case study. The teachers exchanged messages and information within the online community during the 2010-2011 school…

What do external consultants from private and not-for-profit companies offer healthcare commissioners? A qualitative study of knowledge exchange.

PubMed

Wye, Lesley; Brangan, Emer; Cameron, Ailsa; Gabbay, John; Klein, Jonathan H; Anthwal, Rachel; Pope, Catherine

2015-02-25

The use of external consultants from private and not-for-profit providers in the National Health Service (NHS) is intended to improve the quality of commissioning. The aim of this study was to learn about the support offered to healthcare commissioners, how external consultants and their clients work together and the perceived impact on the quality of commissioning. NHS commissioning organisations and private and not-for-profit providers. Mixed methods case study of eight cases. 92 interviews with external consultants (n=36), their clients (n=47) and others (n=9). Observation of 25 training events and meetings. Documentation, for example, meeting minutes and reports. Constant comparison. Data were coded, summarised and analysed by the research team with a coding framework to facilitate cross-case comparison. In the four contracts presented here, external providers offered technical solutions (eg, software tools), outsourcing and expertise including project management, data interpretation and brokering relationships with experts. In assessing perceived impact on quality of commissioning, two contracts had limited value, one had short-term benefits and one provided short and longer term benefits. Contracts with commissioners actively learning, embedding and applying new skills were more valued. Other elements of success were: (1) addressing clearly agreed problems of relevance to managerial and operational staff (2) solutions co-produced at all organisational levels (3) external consultants working directly with clients to interpret data outputs to inform locally contextualised commissioning strategies. Without explicit knowledge exchange strategies, outsourcing commissioning to external providers resulted in the NHS clients becoming dependent. NHS commissioning will be disadvantaged if commissioners both fail to learn in the short term from the knowledge of external providers and in the longer term lose local skills. Knowledge exchange mechanisms are a vital component of commissioning and should be embedded in external provider contracts. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Magnetic properties of Mn-doped GaN with defects: ab-initio calculations

NASA Astrophysics Data System (ADS)

Salmani, E.; Benyoussef, A.; Ez-Zahraouy, H.; H. Saidi, E.

2011-08-01

According to first-principles density functional calculations, we have investigated the magnetic properties of Mn-doped GaN with defects, Ga1-x-yVGxMny N1-z-tVNzOt with Mn substituted at Ga sites, nitrogen vacancies VN, gallium vacancies VG and oxygen substituted at nitrogen sites. The magnetic interaction in Mn-doped GaN favours the ferromagnetic coupling via the double exchange mechanism. The ground state is found to be well described by a model based on a Mn3+-d5 in a high spin state coupled via a double exchange to a partially delocalized hole accommodated in the 2p states of neighbouring nitrogen ions. The effect of defects on ferromagnetic coupling is investigated. It is found that in the presence of donor defects, such as oxygen substituted at nitrogen sites, nitrogen vacancy antiferromagnetic interactions appear, while in the case of Ga vacancies, the interactions remain ferromagnetic; in the case of acceptor defects like Mg and Zn codoping, ferromagnetism is stabilized. The formation energies of these defects are computed. Furthermore, the half-metallic behaviours appear in some studied compounds.

Dzyaloshinskii-Moriya interaction and magnetic anisotropies in Uranium compounds

NASA Astrophysics Data System (ADS)

Sandratskii, L. M.

2018-05-01

We report on the first-principles study of complex noncollinear magnetic structures in Uranium compounds. We contrast two cases. The first is the periodic magnetic structure of U2Pd2In with exactly orthogonal atomic moments, the second is an incommensurate plane spiral structure of UPtGe where the angle between atomic moments of nearest neighbors is also close to 90°. We demonstrate that the hierarchy of magnetic interactions leading to the formation of the magnetic structure is opposite in the two cases. In U2Pd2In, the magnetic anisotropy plays the leading role, followed by the Dzyaloshinskii-Moriya interaction (DMI) interaction specifying the chirality of the structure. Here, the interatomic exchange interaction does not play important role. In UPtGe the hierarchy of the interactions is opposite. The leading interaction is the interatomic exchange interaction responsible for the formation of the incommensurate spiral structure followed by the DMI responsible for the selected chirality of the helix. The magnetic anisotropy is very weak that is a prerequisite for keeping the distortion of the helical structure weak.

Microscopic theory of exchange and dipole-exchange spin waves in magnetic thin films

NASA Astrophysics Data System (ADS)

Pereira, Joao Milton, Jr.

The aim of this work is to develop a microscopic theory of bulk and surface spin wave modes (or magnons) in thin films of some specific ordered magnetic materials, particularly antiferromagnets. Both exchange and magnetic dipole-dipole interactions are taken into account, depending on the material and the wavevector regime. First we study the dispersion relations of spin waves for situations in which the dominant interaction is the short-range exchange coupling between the magnetic sites. We begin by investigating ferromagnetic films with a cubic body centered (b.c.c.) crystal structure a surfaces corresponding to (111) crystal planes. The spin wave frequencies are calculated by a method that generalizes previous techniques used for simpler systems, which allows us to find analytical solutions. The results are then compared with recent experimental data for Ni films grown epitaxially on a W substrate. Then we investigate spin waves in antiferromagnetic systems. Calculations are made for the dispersion relations of exchange-dominated spin waves in antiferromagnetic thin films with simple cubic (s.c.) crystal structures, for three different surface orientations, namely (001), (101) and (111). The results are obtained by using a method similar to the one developed for the ferromagnetic film in the previous chapter. We calculate the effect of finite film thickness in coupling the spin wave modes localized near the two surfaces, leading to a splitting of several of the mode branches that occur in the semi-infinite limit. Another aspect that we consider is the influence, for the (101) orientation, of the direction of propagation on the spin wave frequencies, as well as the effect of non-equivalent sublattices in the (111) case. Next, we investigate the spin waves in antiferromagnetic films made of materials in which the long-range dipole-dipole interaction between the magnetic sites is included, along with the exchange coupling. In this case, we employ a Hamiltonian formalism that uses a transformation of the spin operators to creation and annihilation operators. Initially, we calculate the linear dipole-exchange spin wave spectrum, by considering only the bilinear terms in the transformed Hamiltonian. The theory is applied to antiferromagnetic films with s.c. and b.c.c. structures. The higher-order terms are later included by means of a diagrammatic perturbation technique, which allows us to obtain expressions for the damping and energy shift of the spin wave modes in b.c.c. antiferromagnetic films. Numerical results are then shown for ultrathin films of the antiferromagnet MnF2.

Different Evolutionary Modifications as a Guide to Rewire Two-Component Systems

PubMed Central

Krueger, Beate; Friedrich, Torben; Förster, Frank; Bernhardt, Jörg; Gross, Roy; Dandekar, Thomas

2012-01-01

Two-component systems (TCS) are short signalling pathways generally occurring in prokaryotes. They frequently regulate prokaryotic stimulus responses and thus are also of interest for engineering in biotechnology and synthetic biology. The aim of this study is to better understand and describe rewiring of TCS while investigating different evolutionary scenarios. Based on large-scale screens of TCS in different organisms, this study gives detailed data, concrete alignments, and structure analysis on three general modification scenarios, where TCS were rewired for new responses and functions: (i) exchanges in the sequence within single TCS domains, (ii) exchange of whole TCS domains; (iii) addition of new components modulating TCS function. As a result, the replacement of stimulus and promotor cassettes to rewire TCS is well defined exploiting the alignments given here. The diverged TCS examples are non-trivial and the design is challenging. Designed connector proteins may also be useful to modify TCS in selected cases. PMID:22586357

Raman spectroscopic study of reaction dynamics

NASA Astrophysics Data System (ADS)

MacPhail, R. A.

1990-12-01

The Raman spectra of reacting molecules in liquids can yield information about various aspects of the reaction dynamics. The author discusses the analysis of Raman spectra for three prototypical unimolecular reactions, the rotational isomerization of n-butane and 1,2-difluoroethane, and the barrierless exchange of axial and equatorial hydrogens in cyclopentane via pseudorotation. In the first two cases the spectra are sensitive to torsional oscillations of the gauche conformer, and yield estimates of the torsional solvent friction. In the case of cyclopentane, the spectra can be used to discriminate between different stochastic models of the pseudorotation dynamics, and to determine the relevant friction coefficients.

Prosthetic joint infection caused by Granulicatella adiacens: a case series and review of literature.

PubMed

Quénard, Fanny; Seng, Piseth; Lagier, Jean-Christophe; Fenollar, Florence; Stein, Andreas

2017-06-23

Bone and joint infection involving Granulicatella adiacens is rare, and mainly involved in cases of bacteremia and infectious endocarditis. Here we report three cases of prosthetic joint infection involving G. adiacens that were successfully treated with surgery and prolonged antimicrobial treatment. We also review the two cases of prosthetic joint infection involving G. adiacens that are reported in the literature. Not all five cases of prosthetic joint infection caused by G. adiacens were associated with bacteremia or infectious endocarditis. Dental care before the onset of infection was observed in two cases. The median time delay between arthroplasty implantation and the onset of infection was of 4 years (ranging between 2 and 10 years). One of our cases was identified with 16srRNA gene sequencing, one case with MALDI-TOF mass spectrometry, and one case with both techniques. Two literature cases were diagnosed by 16srRNA gene sequencing. All five cases were cured after surgery including a two-stage prosthesis exchange in three cases, a one-stage prosthesis exchange in one case, and debridement, antibiotics, irrigation, and retention of the prosthesis in one case, and prolonged antimicrobial treatment. Prosthetic joint infection involving G. adiacens is probably often dismissed due to difficult culture or misdiagnosis, in particular in the cases of polymicrobial infection. Debridement, antibiotics, irrigation, and retention of the prosthesis associated with prolonged antimicrobial treatment (≥ 8 weeks) should be considered as a treatment strategy for prosthetic joint infection involving G. adiacens.

Simulation of one-dimensional heat transfer system based on the blended coal combustion

NASA Astrophysics Data System (ADS)

Jin, Y. G.; Li, W. B.; Cheng, Z. S.; Cheng, J. W.; liu, Y.

2017-12-01

In this paper, the supercritical boiler thermodynamic calculation model is studied. Three types of heat exchangers are proposed, namely furnace (total radiation type), semi-radiation and convection, and discussed. Two cases were simulated - mixing of two bituminous coals and mixing of a bituminous coal and lignite- order to analyze the performance on the flue gas side. The study shows that the influence of flue air leakage and gas distribution coefficient on the system.

Vibrational energy transfer between carbon nanotubes and nonaqueous solvents: a molecular dynamics study.

PubMed

Nelson, Tammie R; Chaban, Vitaly V; Prezhdo, Victor V; Prezhdo, Oleg V

2011-05-12

We report molecular dynamics (MD) simulation of energy exchange between single-walled carbon nanotubes (CNTs) and two aprotic solvents, acetonitrile and cyclohexane. Following our earlier study of hydrated CNTs, we find that the time scales and molecular mechanisms of the energy transfer are largely independent of the nature of the surrounding medium, and therefore, should hold for other media including polymer matrices and DNA. The vibrational energy exchange between CNT and solvents exhibits two time-scales. Over half of the energy is transferred in less than one picosecond, indicating that the dominant exchange mechanism is inertial relaxation. It occurs by collisions of solvent molecules with CNT walls, facilitated by the short-range Lennard-Jones interaction. Additional several picoseconds are required for the remainder of the vibrational energy exchange, corresponding to the diffusive relaxation mechanism and involving collective molecular motions. The faster stage of the CNT-solvent energy exchange occurs on the same time-scale, and therefore, competes with the vibrational energy relaxation inside CNTs. The energy exchange time-scales are significantly influenced by the arrangement of solvent molecules inside CNTs. Generally, the effects of confinement on the dynamics can be rationalized by analysis of the solvent structure. For the same CNT diameter, the extent of the confinement effect strongly depends on the size of the solvent molecules. Icelike properties in water seen in small CNTs disappear in CNTs with intermediate diameters. In acetonitrile and cyclohexane, medium size CNTs still show strong confinement effects. Rotational motions of acetonitrile molecules are inhibited, and the cyclohexane density is dramatically decreased. The disbalance between the local temperatures of the inside and outside regions of the solvent equilibrates through a tube-mediated interaction, rather than by a direct coupling between the two solvent subsystems. In all cases, the CNT-solvent energy transfer is mediated by slow motions in the frequency range of CNT radial breathing modes.

Tisettanta case study: the interoperation of furniture production companies

NASA Astrophysics Data System (ADS)

Amarilli, Fabrizio; Spreafico, Alberto

This chapter presents the Tisettanta case study, focusing on the definition of the possible innovations that ICT technologies can bring to the Italian wood-furniture industry. This sector is characterized by industrial clusters composed mainly of a few large companies with international brand reputations and a large base of SMEs that manufacture finished products or are specialized in the production of single components/processes (such as the Brianza cluster, where Tisettanta operates). In this particular business ecosystem, ICT technologies can bring relevant support and improvements to the supply chain process, where collaborations between enterprises are put into action through the exchange of business documents such as orders, order confirmation, bills of lading, invoices, etc. The analysis methodology adopted in the Tisettanta case study refers to the TEKNE Methodology of Change (see Chapter 2), which defines a framework for supporting firms in the adoption of the Internetworked Enterprise organizational paradigm.

Improving approximate-optimized effective potentials by imposing exact conditions: Theory and applications to electronic statics and dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurzweil, Yair; Head-Gordon, Martin

2009-07-15

We develop a method that can constrain any local exchange-correlation potential to preserve basic exact conditions. Using the method of Lagrange multipliers, we calculate for each set of given Kohn-Sham orbitals a constraint-preserving potential which is closest to the given exchange-correlation potential. The method is applicable to both the time-dependent (TD) and independent cases. The exact conditions that are enforced for the time-independent case are Galilean covariance, zero net force and torque, and Levy-Perdew virial theorem. For the time-dependent case we enforce translational covariance, zero net force, Levy-Perdew virial theorem, and energy balance. We test our method on the exchangemore » (only) Krieger-Li-Iafrate (xKLI) approximate-optimized effective potential for both cases. For the time-independent case, we calculated the ground state properties of some hydrogen chains and small sodium clusters for some constrained xKLI potentials and Hartree-Fock (HF) exchange. The results (total energy, Kohn-Sham eigenvalues, polarizability, and hyperpolarizability) indicate that enforcing the exact conditions is not important for these cases. On the other hand, in the time-dependent case, constraining both energy balance and zero net force yields improved results relative to TDHF calculations. We explored the electron dynamics in small sodium clusters driven by cw laser pulses. For each laser pulse we compared calculations from TD constrained xKLI, TD partially constrained xKLI, and TDHF. We found that electron dynamics such as electron ionization and moment of inertia dynamics for the constrained xKLI are most similar to the TDHF results. Also, energy conservation is better by at least one order of magnitude with respect to the unconstrained xKLI. We also discuss the problems that arise in satisfying constraints in the TD case with a non-cw driving force.« less

MAX phase – Alumina composites via exchange reaction in the M{sub n+1}AlC{sub n} systems (M=Ti, V, Cr, Nb, or Ta)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cuskelly, Dylan T., E-mail: Dylan.cuskelly@uon.edu.au; Kisi, Erich H.; Sugo, Heber O.

2016-01-15

MAX phases have been produced for the first time via an exchange reaction between the M-element oxide and Al leading to an M–Al–C–Al{sub 2}O{sub 3} composite in the V–Al–C, Cr–Al–C, Nb–Al–C and Ta–Al–C systems in addition to the previously known Ti–Al–C system. The reduction reaction was first investigated by forming the binary M–X carbide and then proven to be generic across all M–Al–C systems with the production of the M{sub 2}AlC phase in each case. The work was extended to the other M{sub 3}AlC{sub 2} and M{sub 4}AlC{sub 3} phases in the respective systems, and was successful in 4 ofmore » the 5 cases with moderate yield. - Graphical abstract: A range of M{sub n+1}AX{sub n} phases (M-octahedra with X centres and A layers) were synthesised directly from the M oxide via exchange reactions for the 5 M-elements shown. - Highlights: • Ten M{sub n+1}AlC{sub n} phases were produced from M-oxides via a single step exchange reaction. • Eight of these MAX phases had not been produced via this method before. • Al was found to be a suitable reducing agent in all cases. • The process was also discovered to work under SHS and MASHS conditions.« less

Guillain-Barre syndrome in a 7-month-old boy successfully applied plasma exchange.

PubMed

Akarcan, Sanem Eren; İşgüder, Rana; Yılmaz, Ünsal; Ayhan, Yüce; Ceylan, Gökhan; Ağın, Hasan

2016-02-01

Despite being the most common cause of acute flaccid paralysis in children Guillain-Barré syndrome has a low incidence under 18 years old, and is even rarer under the age of 2. Established treatment regimens include intravenous immunoglobulin and plasma exchange in older children and adults. However very limited data are available for the efficacy and safety of plasma exchange in infants younger than 12 month-old. This article presents the experience of plasma exchange in the case of 7-month-old boy diagnosed with Guillain-Barré syndrome. A 7-month-old boy was referred to the pediatric intensive care unit with a 10-day history of progressive weakness, feeding difficulty and constipation. He was diagnosed with axonal Guillain-Barré syndrome on the basis of clinical and electromyographical findings. The patient recovered fully with intravenous immunoglobulin and plasma exchange. Plasma exchange may be a safe option in the treatment in infants with Guillain-Barré syndrome as young as 7-month-age. Copyright © 2016 Elsevier Ltd. All rights reserved.

Spectra Optia® for Automated Red Blood Cell Exchange in Patients with Sickle Cell Disease: A NICE Medical Technology Guidance.

PubMed

Willits, Iain; Cole, Helen; Jones, Roseanne; Carter, Kimberley; Arber, Mick; Jenks, Michelle; Craig, Joyce; Sims, Andrew

2017-08-01

The Spectra Optia ® automated apheresis system, indicated for red blood cell exchange in people with sickle cell disease, underwent evaluation by the National Institute for Health and Care Excellence, which uses its Medical Technologies Advisory Committee to make recommendations. The company (Terumo Medical Corporation) produced a submission making a case for adoption of its technology, which was critiqued by the Newcastle and York external assessment centre. Thirty retrospective observational studies were identified in their clinical submission. The external assessment centre considered these were of low methodological and reporting quality. Most were single-armed studies, with only six studies providing comparative data. The available data showed that, compared with manual red blood cell exchange, Spectra Optia reduces the frequency of exchange procedures as well as their duration, but increases the requirement for donor blood. However, other clinical and patient benefits were equivocal because of an absence of robust clinical evidence. The company provided a de novo model to support the economic proposition of the technology, and reported that in most scenarios Spectra Optia was cost saving, primarily through reduced requirement of chelation therapy to manage iron overload. The external assessment centre considered that although the cost-saving potential of Spectra Optia was plausible, the model and its clinical inputs were not sufficiently robust to demonstrate this. However, taking the evidence together with expert and patient advice, the Medical Technologies Advisory Committee considered Spectra Optia was likely to save costs, provide important patient benefits, and reduce inequality, and gave the technology a positive recommendation in Medical Technology Guidance 28.

Fundamental basis and implementation of shell and tube heat exchanger project design: condenser and evaporator study

NASA Astrophysics Data System (ADS)

Dalkilic, A. S.; Acikgoz, O.; Tapan, S.; Wongwises, S.

2016-12-01

A shell and tube heat exchanger is used as a condenser and an evaporator in this theoretical study. Parametric performance analyses for various actual refrigerants were performed using well-known correlations in open sources. Condensation and evaporation were occurred in the shell side while the water was flowing in the tube side of heat exchanger. Heat transfer rate from tube side was kept constant for condenser and evaporator design. Condensing temperatures were varied from 35 to 60 °C whereas evaporating temperatures were ranging from -15 to 10 °C for the refrigerants of R12, R22, R134a, R32, R507A, R404A, R502, R407C, R152A, R410A and R1234ZE. Variation of convective heat transfer coefficients of refrigerants, total heat transfer coefficients with Reynolds numbers and saturation temperatures were given as validation process considering not only fouling resistance and omission of it but also staggered (triangular) and line (square) arrangements. The minimum tube lengths and necessary pumping powers were calculated and given as case studies for the investigated refrigerants considering validation criteria. It was understood that refrigerant type, fouling resistance and arrangement type are one of the crucial issues regarding the determination of heat exchanger's size and energy consumption. Consequently, R32 and R152a were found to require the shortest tube length and lowest pumping power in the condenser, whereas R507 and R407C have the same advantages in the evaporator. Their heat transfer coefficients were also determined larger than others as expectedly.

Hadronic molecular states from the Kbar{K}^{ast} interaction

NASA Astrophysics Data System (ADS)

Lü, Pei-Liang; He, Jun

2016-12-01

In this work, the Kbar{K}^{ast} interaction is studied in a quasipotential Bethe-Salpeter equation approach combined with the one-boson-exchange model. With the help of the hidden-gauge Lagrangian, the exchanges of pseudoscalar mesons (π and η) and vector mesons (ρ, ω and φ) are considered to describe the Kbar{K}^{ast} interaction. Besides the direct vector-meson exchange which can be related to the Weinberg-Tomozawa term, pseudoscalar-meson exchanges also play important roles in the mechanism of the Kbar{K}^{ast} interaction. The poles of scattering amplitude are searched to find the molecular states produced from the Kbar{K}^{ast} interaction. In the case of quantum number IG(J^{PC}) = 0+(1^{++}), a pole is found with a reasonable cutoff, which can be related to the f1(1285) in experiment. Another bound state with 0-(1^{+-}) is also produced from the Kbar{K}^{ast} interaction, which can be related to the h1(1380). In the isovector sector, the interaction is much weaker and a bound state with 1+(1+) relevant to the b1(1235) is produced but at a larger cutoff. Our results suggest that in the hadronic molecular state picture the f1(1285) and b1(1235) are the strange partners of the X(3872) and Zc(3900), respectively.

Performance analysis of a miniature Joule-Thomson cryocooler with and without the distributed J-T effect

NASA Astrophysics Data System (ADS)

Damle, Rashmin; Atrey, Milind

2015-12-01

Cryogenic temperatures are obtained with Joule-Thomson (J-T) cryocoolers in an easier way as compared to other cooling techniques. Miniature J-T cryocoolers are often employed for cooling of infrared sensors, cryoprobes, biological samples, etc. A typical miniature J-T cryocooler consists of a storage reservoir/compressor providing the high pressure gas, a finned tube recuperative heat exchanger, an expansion valve/orifice, and the cold end. The recuperative heat exchanger is indispensable for attaining cryogenic temperatures. The geometrical parameters and the operating conditions of the heat exchanger drastically affect the cryocooler performance in terms of cool down time and cooling effect. In the literature, the numerical models for the finned recuperative heat exchanger have neglected the distributed J-T effect. The distributed J-T effect accounts for the changes in enthalpy of the fluid due to changes of pressure in addition to those due to changes of temperature. The objective of this work is to explore the distributed J-T effect and study the performance of a miniature J-T cryocooler with and without the distributed J-T effect. A one dimensional transient model is employed for the numerical analysis of the cryocooler. Cases with different operating conditions are worked out with argon and nitrogen as working fluids.

Hidden multidimensional social structure modeling applied to biased social perception

NASA Astrophysics Data System (ADS)

Maletić, Slobodan; Zhao, Yi

2018-02-01

Intricacies of the structure of social relations are realized by representing a collection of overlapping opinions as a simplicial complex, thus building latent multidimensional structures, through which agents are, virtually, moving as they exchange opinions. The influence of opinion space structure on the distribution of opinions is demonstrated by modeling consensus phenomena when the opinion exchange between individuals may be affected by the false consensus effect. The results indicate that in the cases with and without bias, the road toward consensus is influenced by the structure of multidimensional space of opinions, and in the biased case, complete consensus is achieved. The applications of proposed modeling framework can easily be generalized, as they transcend opinion formation modeling.

Quantum communication complexity of establishing a shared reference frame.

PubMed

Rudolph, Terry; Grover, Lov

2003-11-21

We discuss the aligning of spatial reference frames from a quantum communication complexity perspective. This enables us to analyze multiple rounds of communication and give several simple examples demonstrating tradeoffs between the number of rounds and the type of communication. Using a distributed variant of a quantum computational algorithm, we give an explicit protocol for aligning spatial axes via the exchange of spin-1/2 particles which makes no use of either exchanged entangled states, or of joint measurements. This protocol achieves a worst-case fidelity for the problem of "direction finding" that is asymptotically equivalent to the optimal average case fidelity achievable via a single forward communication of entangled states.

Oxygen surface exchange kinetics measurement by simultaneous optical transmission relaxation and impedance spectroscopy: Sr(Ti,Fe)O3-x thin film case study.

PubMed

Perry, Nicola H; Kim, Jae Jin; Tuller, Harry L

2018-01-01

We compare approaches to measure oxygen surface exchange kinetics, by simultaneous optical transmission relaxation (OTR) and AC-impedance spectroscopy (AC-IS), on the same mixed conducting SrTi 0.65 Fe 0.35 O 3-x film. Surface exchange coefficients were evaluated as a function of oxygen activity in the film, controlled by gas partial pressure and/or DC bias applied across the ionically conducting yttria-stabilized zirconia substrate. Changes in measured light transmission through the film over time (relaxations) resulted from optical absorption changes in the film corresponding to changes in its oxygen and oxidized Fe (~Fe 4+ ) concentrations; such relaxation profiles were successfully described by the equation for surface exchange-limited kinetics appropriate for the film geometry. The k chem values obtained by OTR were significantly lower than the AC-IS derived k chem values and k q values multiplied by the thermodynamic factor (bulk or thin film), suggesting a possible enhancement in k by the metal current collectors (Pt, Au). Long-term degradation in k chem and k q values obtained by AC-IS was also attributed to deterioration of the porous Pt current collector, while no significant degradation was observed in the optically derived k chem values. The results suggest that, while the current collector might influence measurements by AC-IS, the OTR method offers a continuous, in situ , and contact-free method to measure oxygen exchange kinetics at the native surfaces of thin films.

Oxygen surface exchange kinetics measurement by simultaneous optical transmission relaxation and impedance spectroscopy: Sr(Ti,Fe)O3-x thin film case study

PubMed Central

Perry, Nicola H.; Kim, Jae Jin; Tuller, Harry L.

2018-01-01

Abstract We compare approaches to measure oxygen surface exchange kinetics, by simultaneous optical transmission relaxation (OTR) and AC-impedance spectroscopy (AC-IS), on the same mixed conducting SrTi0.65Fe0.35O3-x film. Surface exchange coefficients were evaluated as a function of oxygen activity in the film, controlled by gas partial pressure and/or DC bias applied across the ionically conducting yttria-stabilized zirconia substrate. Changes in measured light transmission through the film over time (relaxations) resulted from optical absorption changes in the film corresponding to changes in its oxygen and oxidized Fe (~Fe4+) concentrations; such relaxation profiles were successfully described by the equation for surface exchange-limited kinetics appropriate for the film geometry. The kchem values obtained by OTR were significantly lower than the AC-IS derived kchem values and kq values multiplied by the thermodynamic factor (bulk or thin film), suggesting a possible enhancement in k by the metal current collectors (Pt, Au). Long-term degradation in kchem and kq values obtained by AC-IS was also attributed to deterioration of the porous Pt current collector, while no significant degradation was observed in the optically derived kchem values. The results suggest that, while the current collector might influence measurements by AC-IS, the OTR method offers a continuous, in situ, and contact-free method to measure oxygen exchange kinetics at the native surfaces of thin films. PMID:29511391

Money creation process in a random redistribution model

NASA Astrophysics Data System (ADS)

Chen, Siyan; Wang, Yougui; Li, Keqiang; Wu, Jinshan

2014-01-01

In this paper, the dynamical process of money creation in a random exchange model with debt is investigated. The money creation kinetics are analyzed by both the money-transfer matrix method and the diffusion method. From both approaches, we attain the same conclusion: the source of money creation in the case of random exchange is the agents with neither money nor debt. These analytical results are demonstrated by computer simulations.

17 CFR 240.13e-102 - Schedule 13E-4F. Tender offer statement pursuant to section 13(e) (1) of the Securities Exchange...

Code of Federal Regulations, 2010 CFR

2010-04-01

... is in bankruptcy or receivership or has an accumulated capital deficit, in which case one-third of... Schedule shall be deemed “filed” for purposes of section 18 of the Exchange Act. C. The issuer's attention... reasonably calculated to draw security holder attention to it. Part II—Information Not Required To Be Sent to...

17 CFR 240.14d-102 - Schedule 14D-1F. Tender offer statement pursuant to rule 14d-1(b) under the Securities Exchange...

Code of Federal Regulations, 2010 CFR

2010-04-01

... has an accumulated capital deficit, in which case one-third of the principal amount, par value or... deemed “filed” for purposes of section 18 of the Exchange Act. C. The bidder's attention is directed to... the legend in any manner reasonably calculated to draw security holder attention to it. PART II...

Incorporating water-release and lateral protein interactions in modeling equilibrium adsorption for ion-exchange chromatography.

PubMed

Thrash, Marvin E; Pinto, Neville G

2006-09-08

The equilibrium adsorption of two albumin proteins on a commercial ion exchanger has been studied using a colloidal model. The model accounts for electrostatic and van der Waals forces between proteins and the ion exchanger surface, the energy of interaction between adsorbed proteins, and the contribution of entropy from water-release accompanying protein adsorption. Protein-surface interactions were calculated using methods previously reported in the literature. Lateral interactions between adsorbed proteins were experimentally measured with microcalorimetry. Water-release was estimated by applying the preferential interaction approach to chromatographic retention data. The adsorption of ovalbumin and bovine serum albumin on an anion exchanger at solution pH>pI of protein was measured. The experimental isotherms have been modeled from the linear region to saturation, and the influence of three modulating alkali chlorides on capacity has been evaluated. The heat of adsorption is endothermic for all cases studied, despite the fact that the net charge on the protein is opposite that of the adsorbing surface. Strong repulsive forces between adsorbed proteins underlie the endothermic heat of adsorption, and these forces intensify with protein loading. It was found that the driving force for adsorption is the entropy increase due to the release of water from the protein and adsorbent surfaces. It is shown that the colloidal model predicts protein adsorption capacity in both the linear and non-linear isotherm regions, and can account for the effects of modulating salt.

Multifractal Analysis of Asian Foreign Exchange Markets and Financial Crisis

NASA Astrophysics Data System (ADS)

Oh, Gabjin; Kwon, Okyu; Jung, Woo-Sung

2012-02-01

We analyze the multifractal spectra of daily foreign exchange rates for Japan, Hong-Kong, Korea, and Thailand with respect to the United States Dollar from 1991 to 2005. We find that the return time series show multifractal spectrum features for all four cases. To observe the effect of the Asian currency crisis, we also estimate the multifractal spectra of limited series before and after the crisis. We find that the Korean and Thai foreign exchange markets experienced a significant increase in multifractality compared to Hong-Kong and Japan. We also show that the multifractality is stronge related to the presence of high values of returns in the series.

A multifractal analysis of Asian foreign exchange markets

NASA Astrophysics Data System (ADS)

Oh, G.; Eom, C.; Havlin, S.; Jung, W.-S.; Wang, F.; Stanley, H. E.; Kim, S.

2012-06-01

We analyze the multifractal spectra of daily foreign exchange rates for Japan, Hong-Kong, Korea, and Thailand with respect to the United States in the period from 1991 until 2005. We find that the return time series show multifractal spectrum features for all four cases. To observe the effect of the Asian currency crisis, we also estimate the multifractal spectra of limited series before and after the crisis. We find that the Korean and Thai foreign exchange markets experienced a significant increase in multifractality compared to Hong-Kong and Japan. We also show that the multifractality is stronger related to the presence of high values of returns in the series.

Neuroanatomical Diversity of Corpus Callosum and Brain Volume in Autism: Meta-analysis, Analysis of the Autism Brain Imaging Data Exchange Project, and Simulation.

PubMed

Lefebvre, Aline; Beggiato, Anita; Bourgeron, Thomas; Toro, Roberto

2015-07-15

Patients with autism have been often reported to have a smaller corpus callosum (CC) than control subjects. We conducted a meta-analysis of the literature, analyzed the CC in 694 subjects of the Autism Brain Imaging Data Exchange project, and performed computer simulations to study the effect of different analysis strategies. Our meta-analysis suggested a group difference in CC size; however, the studies were heavily underpowered (20% power to detect Cohen's d = .3). In contrast, we did not observe significant differences in the Autism Brain Imaging Data Exchange cohort, despite having achieved 99% power. However, we observed that CC scaled nonlinearly with brain volume (BV): large brains had a proportionally smaller CC. Our simulations showed that because of this nonlinearity, CC normalization could not control for eventual BV differences, but using BV as a covariate in a linear model would. We also observed a weaker correlation of IQ and BV in cases compared with control subjects. Our simulations showed that matching populations by IQ could then induce artifactual BV differences. The lack of statistical power in the previous literature prevents us from establishing the reality of the claims of a smaller CC in autism, and our own analyses did not find any. However, the nonlinear relationship between CC and BV and the different correlation between BV and IQ in cases and control subjects may induce artifactual differences. Overall, our results highlight the necessity for open data sharing to provide a more solid ground for the discovery of neuroimaging biomarkers within the context of the wide human neuroanatomical diversity. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

A cooperative model for IS security risk management in distributed environment.

PubMed

Feng, Nan; Zheng, Chundong

2014-01-01

Given the increasing cooperation between organizations, the flexible exchange of security information across the allied organizations is critical to effectively manage information systems (IS) security in a distributed environment. In this paper, we develop a cooperative model for IS security risk management in a distributed environment. In the proposed model, the exchange of security information among the interconnected IS under distributed environment is supported by Bayesian networks (BNs). In addition, for an organization's IS, a BN is utilized to represent its security environment and dynamically predict its security risk level, by which the security manager can select an optimal action to safeguard the firm's information resources. The actual case studied illustrates the cooperative model presented in this paper and how it can be exploited to manage the distributed IS security risk effectively.

Effect of land use on greenhouse gas emission in tropical ecosystems

NASA Astrophysics Data System (ADS)

Six, Johan

2017-04-01

Tropical ecosystems play an important role for the regional and global climate system through the exchange of greenhouse gases and provide important ecosystems services such as carbon sequestration, produce, and biodiversity. Human activities have, however, resulted in intensive transformation of tropical ecosystems impacting the cycling of nutrients, water and carbon underlying the greenhouse gas emissions. At the same time, best-bet agricultural practices can reduce greenhouse gas emission, those directly emitted from the agricultural fields, but also indirectly through less demand on new land and hence forest conservation. Here, I will provide some insights into the main factors affecting the exchange of greenhouse gases from the plot to continental scale through some specific case studies. Experimental data, stable isotopes and modeling results will be presented.

The Economic and Social Value of an Image Exchange Network: A Case for the Cloud.

PubMed

Mayo, Ray Cody; Pearson, Kathryn L; Avrin, David E; Leung, Jessica W T

2017-01-01

As the health care environment continually changes, radiologists look to the ACR's Imaging 3.0 ® initiative to guide the search for value. By leveraging new technology, a cloud-based image exchange network could provide secure universal access to prior images, which were previously siloed, to facilitate accurate interpretation, improved outcomes, and reduced costs. The breast imaging department represents a viable starting point given the robust data supporting the benefit of access to prior imaging studies, existing infrastructure for image sharing, and the current workflow reliance on prior images. This concept is scalable not only to the remainder of the radiology department but also to the broader medical record. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Physicochemical characterisation of natural K-clinoptilolite and heavy-metal forms from Gördes (Manisa, western Turkey)

NASA Astrophysics Data System (ADS)

Ünaldı, Tevfik; Mızrak, İbrahim; Kadir, Selahattin

2013-12-01

Physicochemical characterisation of natural K-clinoptilolite and heavy-metal (Ag+, Cd2+, Cr3+ and Co3+) forms was accomplished through ion exchange by batch, X-ray diffractometric (XRD), X-ray fluorescence (XRF), infrared-spectral (FT-IR), differential thermal analysis-thermal gravimetric (DTA-TG) and scanning-electron microscopic (SEM) methods. Increasing the normality in the cases of heavy-metal forms resulted in decrease in crystallinity and increases in unit-cell volume, rate of ion exchange, and percentage of ion selectivity. In this study, the order of ion-selectivity percentages (rather than ion selectivity) of heavy-metal forms was determined to be Ag+ > Cd2+ > Cr3+ > Co3+. This finding is consistent with the results of worldwide research on the order of ion selectivity in modified clinoptilolite.

Reverse ion exchange as a major process controlling the groundwater chemistry in an arid environment: a case study from northwestern Saudi Arabia.

PubMed

Zaidi, Faisal K; Nazzal, Yousef; Jafri, Muhammad Kamran; Naeem, Muhammad; Ahmed, Izrar

2015-10-01

Assessment of groundwater quality is of utmost significance in arid regions like Saudi Arabia where the lack of present-day recharge and high evaporation rates coupled with increasing groundwater withdrawal may restrict its usage for domestic or agricultural purposes. In the present study, groundwater samples collected from agricultural farms in Hail (15 samples), Al Jawf (15 samples), and Tabuk (30 samples) regions were analyzed for their major ion concentration. The objective of the study was to determine the groundwater facies, the main hydrochemical process governing the groundwater chemistry, the saturation index with respect to the principal mineral phases, and the suitability of the groundwater for irrigational use. The groundwater samples fall within the Ca-Cl type, mixed Ca-Mg-Cl type, and Na-Cl type. Evaporation and reverse ion exchange appear to be the major processes controlling the groundwater chemistry though reverse ion exchange process is the more dominating factor. The various ionic relationships confirmed the reverse ion exchange process where the Ca and Mg in the aquifer matrix have been replaced by Na at favorable exchange sites. This phenomenon has accounted for the dominance of Ca and Mg ions over Na ion at all the sites. The process of reverse ion exchange was further substantiated by the use of modified Piper diagram (Chadha's classification) and the chloro-alkaline indices. Evaporation as a result of extreme aridity has resulted in the groundwater being oversaturated with aragonite/calcite and dolomite as revealed by the saturation indices. The groundwater samples were classified as safe (less than 10) in terms of sodium adsorption ratio (SAR) values, good (less than 1.25) in terms of residual sodium carbonate (RSC) values, and safe to moderate (between 0 and 3) in terms of Mg hazard for irrigation purposes. Though the high salinity groundwater in the three regions coupled with low SAR values are good for the soil structure, it can have a negative impact on the crop production by adversely affecting the crop physiology. Cultivation of high-salinity-resistant varieties of crops is recommended for maximum agricultural productivity.

Impact of transient stream flow on water exchange and reactions in the hyporheic zone of an in-stream gravel bar

NASA Astrophysics Data System (ADS)

Trauth, Nico; Schmidt, Christian; Fleckenstein, Jan H.

2015-04-01

Groundwater-surface water exchange is an important process that can facilitate the degradation of critical substances like nitrogen-species and contaminants, supporting a healthy status of the aquatic ecosystem. In our study, we simulate water exchange, solute transport and reactions within a natural in-stream gravel bar using a coupled surface and subsurface numerical model. Stream water flow is simulated by computational fluid dynamics software that provides hydraulic head distributions at the streambed, which are used as an upper boundary condition for a groundwater model. In the groundwater model water exchange, solute transport, aerobic respiration and denitrification in the subsurface are simulated. Ambient groundwater flow is introduced by lateral upstream and downstream hydraulic head boundaries that generate neutral, losing or gaining stream conditions. Stream water transports dissolved oxygen, organic carbon (as the dominant electron donor) and nitrate into the subsurface, whereas an additional nitrate source exists in the ambient groundwater. Scenarios of stream flow events varying in duration and stream stage are simulated and compared with steady state scenarios with respect to water fluxes, residence times and the solute turn-over rates. Results show, that water exchange and solute turn-over rates highly depend on the interplay between event characteristics and ambient groundwater levels. For scenarios, where the stream flow event shifts the hydraulic system to a net-neutral hydraulic gradient between the average stream stage and the ambient groundwater level (minimal exchange between ground- and surface water), solute consumption is higher, compared to the steady losing or gaining case. In contrast, events that induce strong losing conditions lead to a lower potential of solute consumption.

Swinger RNAs with sharp switches between regular transcription and transcription systematically exchanging ribonucleotides: Case studies.

PubMed

Seligmann, Hervé

2015-09-01

During RNA transcription, DNA nucleotides A,C,G, T are usually matched by ribonucleotides A, C, G and U. However occasionally, this rule does not apply: transcript-DNA homologies are detectable only assuming systematic exchanges between ribonucleotides. Nine symmetric (X ↔ Y, e.g. A ↔ C) and fourteen asymmetric (X ↔ Y ↔ Z, e.g. A ↔ C ↔ G) exchanges exist, called swinger transcriptions. Putatively, polymerases occasionally stabilize in unspecified swinger conformations, possibly similar to transient conformations causing punctual misinsertions. This predicts chimeric transcripts, part regular, part swinger-transformed, reflecting polymerases switching to swinger polymerization conformation(s). Four chimeric Genbank transcripts (three from human mitochondrion and one murine cytosolic) are described here: (a) the 5' and 3' extremities reflect regular polymerization, the intervening sequence exchanges systematically between ribonucleotides (swinger rule G ↔ U, transcript (1), with sharp switches between regular and swinger sequences; (b) the 5' half is 'normal', the 3' half systematically exchanges ribonucleotides (swinger rule C ↔ G, transcript (2), with an intercalated sequence lacking homology; (c) the 3' extremity fits A ↔ G exchanges (10% of transcript length), the 5' half follows regular transcription; the intervening region seems a mix of regular and A ↔ G transcriptions (transcript 3); (d) murine cytosolic transcript 4 switches to A ↔ U + C ↔ G, and is fused with A ↔ U + C ↔ G swinger transformed precursor rRNA. In (c), each concomitant transcript 5' and 3' extremities match opposite genome strands. Transcripts 3 and 4 combine transcript fusions with partial swinger transcriptions. Occasional (usually sharp) switches between regular and swinger transcriptions reveal greater coding potential than detected until now, suggest stable polymerase swinger conformations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Theoretical investigation on the mechanism and dynamics of oxo exchange of neptunyl(VI) hydroxide in aqueous solution.

PubMed

Yang, Xia; Chai, Zhifang; Wang, Dongqi

2015-03-21

Four types of reaction mechanisms for the oxo ligand exchange of monomeric and dimeric neptunyl(VI) hydroxide in aqueous solution were explored computationally using density functional theory (DFT) and ab initio classical molecular dynamics. The obtained results were compared with previous studies on the oxo exchange of uranyl hydroxide, as well as with experiments. It is found that the stable T-shaped [NpO3(OH)3](3-) intermediate is a key species for oxo exchange in the proton transfer in mononuclear Path I and binuclear Path IV, similar to the case of uranyl(VI) hydroxide. Path I is thought to be the preferred oxo exchange mechanism for neptunyl(VI) hydroxide in our calculations, due to the lower activation energy (22.7 and 13.1 kcal mol(-1) for ΔG(‡) and ΔH(‡), respectively) of the overall reaction. Path II via a cis-neptunyl structure assisted by a water molecule might be a competitive channel against Path I with a mononuclear mechanism, owing to a rapid dynamical process occurring in Path II. In Path IV with the binuclear mechanism, oxo exchange is accomplished via the interaction between [NpO2(OH)4](2-) and T-shaped [NpO3(OH)3](3-) with a low activation energy for the rate-determining step, however, the overall energy required to fulfill the reaction is slightly higher than that in mononuclear Path I, suggesting a possible binuclear process in the higher energy region. The chemical bonding evolution along the reaction pathways was discussed by using topological methodologies of the electron localization function (ELF).

20 CFR 418.3125 - What are redeterminations?

Code of Federal Regulations, 2010 CFR

2010-04-01

... from data exchanges with Federal and State agencies that may affect whether you should receive a full... random sample of cases for quality assurance purposes. For each collection of sample cases, all factors... with primary repositories of information relevant to each individual factor (e.g., we may contact...

Numerical Simulations of Particle Deposition in Metal Foam Heat Exchangers

NASA Astrophysics Data System (ADS)

Sauret, Emilie; Saha, Suvash C.; Gu, Yuantong

2013-01-01

Australia is a high-potential country for geothermal power with reserves currently estimated in the tens of millions of petajoules, enough to power the nation for at least 1000 years at current usage. However, these resources are mainly located in isolated arid regions where water is scarce. Therefore, wet cooling systems for geothermal plants in Australia are the least attractive solution and thus air-cooled heat exchangers are preferred. In order to increase the efficiency of such heat exchangers, metal foams have been used. One issue raised by this solution is the fouling caused by dust deposition. In this case, the heat transfer characteristics of the metal foam heat exchanger can dramatically deteriorate. Exploring the particle deposition property in the metal foam exchanger becomes crucial. This paper is a numerical investigation aimed to address this issue. Two-dimensional (2D) numerical simulations of a standard one-row tube bundle wrapped with metal foam in cross-flow are performed and highlight preferential particle deposition areas.

Analytical Description of the H/D Exchange Kinetic of Macromolecule.

PubMed

Kostyukevich, Yury; Kononikhin, Alexey; Popov, Igor; Nikolaev, Eugene

2018-04-17

We present the accurate analytical solution obtained for the system of rate equations describing the isotope exchange process for molecules containing an arbitrary number of equivalent labile atoms. The exact solution was obtained using Mathematica 7.0 software, and this solution has the form of the time-dependent Gaussian distribution. For the case when forward exchange considerably overlaps the back exchange, it is possible to estimate the activation energy of the reaction by obtaining a temperature dependence of the reaction degree. Using a previously developed approach for performing H/D exchange directly in the ESI source, we have estimated the activation energies for ions with different functional groups and they were found to be in a range 0.04-0.3 eV. Since the value of the activation energy depends on the type of functional group, the developed approach can have potential analytical applications for determining types of functional groups in complex mixtures, such as petroleum, humic substances, bio-oil, and so on.

Diagnosis Of Persistent Infection In Prosthetic Two-Stage Exchange: PCR analysis of Sonication fluid From Bone Cement Spacers.

PubMed

Mariaux, Sandrine; Tafin, Ulrika Furustrand; Borens, Olivier

2017-01-01

Introduction: When treating periprosthetic joint infections with a two-stage procedure, antibiotic-impregnated spacers are used in the interval between removal of prosthesis and reimplantation. According to our experience, cultures of sonicated spacers are most often negative. The objective of our study was to investigate whether PCR analysis would improve the detection of bacteria in the spacer sonication fluid. Methods: A prospective monocentric study was performed from September 2014 to January 2016. Inclusion criteria were two-stage procedure for prosthetic infection and agreement of the patient to participate in the study. Beside tissues samples and sonication, broad range bacterial PCRs, specific S. aureus PCRs and Unyvero-multiplex PCRs were performed on the sonicated spacer fluid. Results: 30 patients were identified (15 hip, 14 knee and 1 ankle replacements). At reimplantation, cultures of tissue samples and spacer sonication fluid were all negative. Broad range PCRs were all negative. Specific S. aureus PCRs were positive in 5 cases. We had two persistent infections and four cases of infection recurrence were observed, with bacteria different than for the initial infection in three cases. Conclusion: The three different types of PCRs did not detect any bacteria in spacer sonication fluid that was culture-negative. In our study, PCR did not improve the bacterial detection and did not help to predict whether the patient will present a persistent or recurrent infection. Prosthetic 2-stage exchange with short interval and antibiotic-impregnated spacer is an efficient treatment to eradicate infection as both culture- and molecular-based methods were unable to detect bacteria in spacer sonication fluid after reimplantation.

Success in health information exchange projects: solving the implementation puzzle.

PubMed

Sicotte, Claude; Paré, Guy

2010-04-01

Interest in health information exchange (HIE), defined as the use of information technology to support the electronic transfer of clinical information across health care organizations, continues to grow among those pursuing greater patient safety and health care accessibility and efficiency. In this paper, we present the results of a longitudinal multiple-case study of two large-scale HIE implementation projects carried out in real time over 3-year and 2-year periods in Québec, Canada. Data were primarily collected through semi-structured interviews (n=52) with key informants, namely implementation team members and targeted users. These were supplemented with non-participants observation of team meetings and by the analysis of organizational documents. The cross-case comparison was particularly relevant given that project circumstances led to contrasting outcomes: while one project failed, the other was a success. A risk management analysis was performed taking a process view in order to capture the complexity of project implementations as evolving phenomena that are affected by interdependent pre-existing and emergent risks that tend to change over time. The longitudinal case analysis clearly demonstrates that the risk factors were closely intertwined. Systematic ripple effects from one risk factor to another were observed. This risk interdependence evolved dynamically over time, with a snowball effect that rendered a change of path progressively more difficult as time passed. The results of the cross-case analysis demonstrate a direct relationship between the quality of an implementation strategy and project outcomes. Copyright 2010 Elsevier Ltd. All rights reserved.

Patient-clinician mobile communication: analyzing text messaging between adolescents with asthma and nurse case managers.

PubMed

Yoo, Woohyun; Kim, Soo Yun; Hong, Yangsun; Chih, Ming-Yuan; Shah, Dhavan V; Gustafson, David H

2015-01-01

With the increasing penetration of digital mobile devices among adolescents, mobile texting messaging is emerging as a new channel for patient-clinician communication for this population. In particular, it can promote active communication between healthcare clinicians and adolescents with asthma. However, little is known about the content of the messages exchanged in medical encounters via mobile text messaging. Therefore, this study explored the content of text messaging between clinicians and adolescents with asthma. We collected a total of 2,953 text messages exchanged between 5 nurse case managers and 131 adolescents with asthma through a personal digital assistant. The text messages were coded using a scheme developed by adapting categories from the Roter Interaction Analysis System. Nurse case managers sent more text messages (n=2,639) than adolescents with asthma. Most messages sent by nurse case managers were targeted messages (n=2,475) directed at all adolescents with asthma, whereas there were relatively few tailored messages (n=164) that were created personally for an individual adolescent. In addition, both targeted and tailored messages emphasized task-focused behaviors over socioemotional behaviors. Likewise, text messages (n=314) sent by adolescents also emphasized task-focused over socioemotional behaviors. Mobile texting messaging has the potential to play an important role in patient-clinician communication. It promotes not only active interaction, but also patient-centered communication with clinicians. In order to achieve this potential, healthcare clinicians may need to focus on socioemotional communication as well as task-oriented communication.

Structural Studies of NH4-exchanged Natrolites at Ambient Conditions and High Temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Y Lee; D Seoung; Y Jang

2011-12-31

We report here for the first time that fully and partially NH{sub 4}-exchanged natrolites can be prepared in hydrated states using the solution exchange method with potassium-natrolite. The structural models of the as-prepared hydrated phases and their dehydrated forms at elevated temperature were refined in space group Fdd2 using in situ synchrotron X-ray powder diffraction data and Rietveld methods. The unit-cell volumes of the hydrated NH{sub 4}-exchanged natrolites at ambient conditions, (NH{sub 4}){sub 16(2)}Al{sub 16}Si{sub 24}O{sub 80}{center_dot}14.1(9)H{sub 2}O and (NH{sub 4}){sub 5.1(1)}K{sub 10.9(1)}Al{sub 16}Si{sub 24}O{sub 80}{center_dot}15.7(3)H{sub 2}O, are found to be larger than that the original sodium-natrolite by ca. 15.6%more » and 12.8%, respectively. Upon temperature increase, the fully NH{sub 4}-exchanged natrolite undergoes dehydration at ca. 150 C with ca. 16.4% contraction in the unit-cell volume. The dehydrated phase of the fully NH{sub 4}-exchanged natrolite exhibits marginal volume expansion up to 425 C and then becomes amorphized during temperature decrease and exposure to atmospheric condition. In the case of the partially NH{sub 4}-exchanged natrolite, the dehydration starts from ca. 175 C with {approx}15.1% volume contraction and leads to a partial phase separation to show a phase related to the dehydrated K-natrolite. The degree of the phase separation decreases with temperature increase up to 475 C, concomitant to the gradual volume contraction occurring in the partially NH{sub 4}-exchanged natrolite in the dehydrared state. Upon temperature decrease and exposure to atmospheric condition, only the dehydrated K-natrolite is recovered as a crystalline phase from the partially NH{sub 4}-exchanged natrolite. In the hydrated model of the fully NH{sub 4}-exchanged natrolite, the ammonium cations and water molecules are statistically distributed along the elliptical channels, similar to the disordered pattern observed in natrolites exchanged with larger alkali metal cations such as the K-, Rb-, and Cs-forms. The dehydrated model of the fully NH{sub 4}-exchanged natrolite at 400 C is essentially same as the one reported previously from the sample prepared by direct melt exchange method using sodium-natrolite. Both the hydrated and dehydrated structures of the partially NH{sub 4}-exchanged natrolite at RT and at 400 C, respectively, are characterized by having two separate sites for the ammonium and potassium cations. Comparing the structural models of the monovalent cation forms studied so far, we find that the rotation angle of the natrolite chain is inversely proportional to the cation radius both in the hydrated and dehydrated phases. The distribution pattern of the non-framework species along the natrolite channel also seems to be related to the non-framework cation radius and hence to the chain rotation angle.« less

Unsatisfactory clinical outcomes of second-generation mobile bearing floating platform total knee arthroplasty: comparing outcomes with fixed bearing after five years minimum.

PubMed

Yoon, Jung-Ro; Yang, Jae-Hyuk

2018-03-20

The purpose of this retrospective study was to analyze and compare the clinical and radiologic outcomes of fixed bearing ultracongruent (UC) insert total knee arthroplasty (TKA) and mobile bearing (MB) floating platform TKA using the navigation-assisted gap balancing technique with a minimum follow-up of five years. The study retrospectively enrolled 105 patients who received the UC type fixed bearing insert (group 1) and 95 patients who received the floating platform MB insert (group 2) during the period from August 2009 to June 2012. All surgery was performed using the navigation-assisted gap balancing technique. For strict assessment of gap measurements, the offset-type-force-controlled-spreader-system was used. Radiologic and clinical outcomes were assessed before operation and at the most recent follow-up using the Knee Society Score (KSS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. For statistical analysis, paired sample t tests were used. A p value less than 0.05 was considered significant. Although the radiologic alignments were satisfactory for both groups (99/105 [94%] cases were neutral for group 1 and 90/95 [94%] for group 2), the functional and total WOMAC scores were inferior in group 2 (p < 0.05). There were two cases of insert breakage in group 2 that required bearing exchange. The Kaplan-Meier survivorship rates for groups 1 and 2 at 77 months were 100.0 and 97.9%, respectively. Second-generation MB floating platform TKA cases did not have satisfactory outcomes. There were two cases of insert breakage, which required bearing exchange. Other patients who underwent surgery with second-generation MB floating platform were encouraged to avoid high knee flexion activities, resulting in lower clinical performance.

Subsystem functional and the missing ingredient of confinement physics in density functionals.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Armiento, Rickard Roberto; Mattsson, Ann Elisabet; Hao, Feng

2010-08-01

The subsystem functional scheme is a promising approach recently proposed for constructing exchange-correlation density functionals. In this scheme, the physics in each part of real materials is described by mapping to a characteristic model system. The 'confinement physics,' an essential physical ingredient that has been left out in present functionals, is studied by employing the harmonic-oscillator (HO) gas model. By performing the potential {yields} density and the density {yields} exchange energy per particle mappings based on two model systems characterizing the physics in the interior (uniform electron-gas model) and surface regions (Airy gas model) of materials for the HO gases,more » we show that the confinement physics emerges when only the lowest subband of the HO gas is occupied by electrons. We examine the approximations of the exchange energy by several state-of-the-art functionals for the HO gas, and none of them produces adequate accuracy in the confinement dominated cases. A generic functional that incorporates the description of the confinement physics is needed.« less

Reaction limited aggregation in surfactant-mediated epitaxy

NASA Astrophysics Data System (ADS)

Wu, Jing; Liu, Bang-Gui; Zhang, Zhenyu; Wang, E. G.

2000-05-01

A theoretical model for reaction limited aggregation (RLA) is introduced to study the effect of a monolayer of surfactant on the formation of two-dimensional islands in heteroepitaxial and homoepitaxial growth. In this model the basic atomic processes are considered as follows. A stable island consists of the adatoms that have exchanged positions with the surfactant atoms beneath them. Movable active adatoms may (a) diffuse on the surfactant terrace, (b) exchange positions with the surfactant atoms beneath them and become island seeds (seed exchange), or (c) stick to stable islands and become stuck but still active adatoms. The rate-limiting step for the formation of a stable island is the seed exchange. Furthermore, a stuck but still active adatom must overcome a sizable potential-energy barrier to exchange positions with the surfactant atom beneath it and become a member of the stable island (aided exchange). The seed exchange process can occur with an adatom or collectively with an addimer. In the case of dimer exchange, the diffusing adatoms on the surfactant terrace can meet and (after exchanging) form stable dimers, which can then become island seeds. Systematic kinetic Monte Carlo simulations and rate-equation analysis of the model are carried out. The key finding of these simulations is that a counterintuitive fractal-to-compact island shape transition can be induced either by increasing deposition flux or by decreasing growth temperature. This major qualitative conclusion is valid for both the monomer and the dimer seed exchanges and for two different substrate lattices (square and triangular, respectively), although there are some quantitative differences in the flux and temperature dependence of the island density. The shape transition observed is contrary to the prediction of the classic diffusion-limited aggregation (DLA) theory, but in excellent qualitative agreement with recent experiments. In rationalizing the main finding, it is crucial to realize that the adatoms stuck to a stable island edge are still active and are surrounded by the surfactant atoms. Therefore, these stuck atoms cannot capture incoming adatoms before they join the island through aided exchange. As a result, an incoming adatom must on average hit the island many times before it finally finds a free edge site to stick to. This search is effectively equivalent to edge diffusion in DLA theory. The stuck adatoms thus act as shields which prevent other mobile adatoms from sticking to the stable islands. This shielding effect, determined by the aided exchange barrier and the density of the mobile adatoms, plays an essential role in inducing the above shape transition in surfactant-mediated epitaxial growth.

International outbreak investigation of Salmonella Heidelberg associated with in-flight catering.

PubMed

Rebolledo, J; Garvey, P; Ryan, A; O'Donnell, J; Cormican, M; Jackson, S; Cloak, F; Cullen, L; Swaan, C M; Schimmer, B; Appels, R W; Nygard, K; Finley, R; Sreenivasan, N; Lenglet, A; Gossner, C; McKeown, P

2014-04-01

Rapid and wide dispersal of passengers after flights makes investigation of flight-related outbreaks challenging. An outbreak of Salmonella Heidelberg was identified in a group of Irish travellers returning from Tanzania. Additional international cases sharing the same flight were identified. Our aim was to determine the source and potential vehicles of infection. Case-finding utilized information exchange using experts' communication networks and national surveillance systems. Demographic, clinical and food history information was collected. Twenty-five additional cases were identified from Ireland, The Netherlands, Norway, USA and Canada. We conducted a case-control study which indicated a significant association between illness and consumption of milk tart (OR 10.2) and an egg dish (OR 6) served on-board the flight. No food consumed before the flight was associated with illness. Cases from countries other than Ireland provided supplementary information that facilitated the identification of likely vehicles of infection. Timely, committed international collaboration is vital in such investigations.

Pattern analysis of fraud case in Taiwan, China and Indonesia

NASA Astrophysics Data System (ADS)

Kusumo, A. H.; Chi, C.-F.; Dewi, R. S.

2017-11-01

The current study analyzed 125 successful fraud cases happened in Taiwan, China, and Indonesia from 2008 to 2012 published in the English online newspapers. Each of the case report was coded in terms of scam principle, information media (information exchange between fraudsters and victim), money media (media used by fraudsters to obtain unauthorized financial benefit) and other additional information which was judged to be relevant. The Chi-square Automatic Interaction Detector (CHAID) was applied to the coded data of information, scam principle and money media to find a subset of predictors that might derive meaningful classifications. A series of flow diagrams was constructed based on CHAID result to illustrate the flow of information (scam) travelling from information media to money media.

Why Give?: Exploring Social Exchange and Organization Identification Theories in the Promotion of Philanthropic Behaviors of African-American Millennials at Private-HBCUs

ERIC Educational Resources Information Center

Drezner, Noah D.

2009-01-01

African Americans give a larger percentage of their disposable income to non-profits than any other racial group, including Whites. However, there is a lack of literature on Black giving to higher education. This lack of research is particularly acute in our current state of decreased funding to higher education. This case study of the United…