Effect of nanosized Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} on the transport critical current density of Bi{sub 1.6}Pb{sub 0.4}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} superconductor

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

Hafiz, M.; Abd-Shukor, R.

2014-09-03

The effects of nano-sized Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} addition on the superconducting and transport properties of Bi{sub 1.6}Pb{sub 0.4}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} (Bi-2223) in bulk form has been investigated. Bi-2223 superconductor was fabricated using co-precipitation method and 0.01 – 0.05 wt% of Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} nanoparticles with average size of 20 nm were added into the samples. The critical temperature (T{sub c}) and critical current density (J{sub c}) of the samples were measured by using the four-point probe method, while the phase formation and microstructure of the samples were examined using x-ray diffraction and SEM respectively.more » It was found that J{sub c} of all samples added with Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} were higher than non-added sample, with x = 0.01 wt. % sample showing the highest J{sub c}. This study showed that small addition of nano-Co{sub 0.5}Ni{sub 0.5}Fe{sub 2}O{sub 4} can effectively enhance the transport critical current density in Bi-2223 superconductor.« less

Effect of addition of nanoparticle TiO 2/SiO 2 on the superconducting properties of MgB 2

NASA Astrophysics Data System (ADS)

Zhang, Y.; Zhou, S. H.; Wang, X. L.; Dou, S. X.

2008-09-01

In this paper, bulk MgB 2 was prepared by doping with nanoparticle TiO 2 surface-modified by 5-10% SiO 2. The doping ratio of TiO 2/SiO 2 to MgB 2 was 0, 5, 10, and 15 wt%. The sintering temperature varied from 650 °C to 950 °C. Quantitative X-ray diffraction (XRD) analysis was performed to obtain the lattice constants and the weight fraction of impurities using the Rietveld method. It was found that the critical temperature ( Tc) increases with the lattice constants. The critical current density ( Jc) is affected by the doping ratio and the sintering temperature. The Jc exhibited the highest value at the doping ratio of 10 wt% for 5 K and 20 K and at the doping ratio of 5 wt% for 30 K, when the sintering temperature was fixed at 750 °C. When the doping ratio was fixed at 5 wt%, the samples with the sintering temperature of 750 °C had the best Jc for 5 K and 20 K, while the sample with the sintering temperature of 850 °C exhibited the highest Jc at 30 K.

Redundant actuator development study. [flight control systems for supersonic transport aircraft

NASA Technical Reports Server (NTRS)

Ryder, D. R.

1973-01-01

Current and past supersonic transport configurations are reviewed to assess redundancy requirements for future airplane control systems. Secondary actuators used in stability augmentation systems will probably be the most critical actuator application and require the highest level of redundancy. Two methods of actuator redundancy mechanization have been recommended for further study. Math models of the recommended systems have been developed for use in future computer simulations. A long range plan has been formulated for actuator hardware development and testing in conjunction with the NASA Flight Simulator for Advanced Aircraft.

High-performance MgB2 superconducting wires for use under liquid-helium-free conditions fabricated using an internal Mg diffusion process

NASA Astrophysics Data System (ADS)

Ye, ShuJun; Song, Minghui; Matsumoto, Akiyoshi; Togano, Kazumasa; Takeguchi, Masaki; Ohmura, Takahito; Kumakura, Hiroaki

2013-12-01

MgB2 has a superconducting transition temperature (Tc) of 39 K, which is much higher than that for practical metallic superconductors. Thus, it is hoped that MgB2 can not only replace metallic superconductors, but can be used under liquid-helium-free conditions, for example, at temperatures of 10-20 K that can easily be achieved using cryocooling systems. However, to date, the reported critical current density (Jc) for MgB2 wires is not high enough for large-scale applications in liquid-helium-free conditions. In the present study, successful fabrication of high-performance MgB2 superconducting wires was carried out using an internal Mg diffusion (IMD) process, involving a p-dimethylbenzene (C8H10) pre-treatment of carbon-coated B powder with nanometer-sized particles. The resulting wires exhibited the highest ever Jc of 1.2 × 105 A cm-2 at 4.2 K and 10 T, and an engineering critical current density (Je) of about 1 × 104 A cm-2. Not only in 4.2 K, but also in 10 K, the Jc values for the wires fabricated in the present study are in fact higher than that for Nb-Ti wires at 4.2 K for the magnetic fields at which the measurements were carried out. At 20 K and 5 T, the Jc and Je were about 7.6 × 105 A cm-2 and 5.3 × 103 A cm-2, respectively, which are the highest values reported for MgB2 wires to date. The results of a detailed microstructural analysis suggested that the main reason for the superior electrical performance was the high density of the MgB2 layer rather than just the small grain size, and that the critical current could be further increased by suitable control of the microstructure. These high-performance IMD-processed MgB2 wires are thus promising superconductors for applications such as magnetic resonance imaging and maglev trains that can operate under liquid-helium-free conditions.

Aerospace devices for magnetic replicas

NASA Technical Reports Server (NTRS)

Weinstein, Roy

1993-01-01

Retained persistent magnetic field has been studied and improved in the superconductor YBa2Cu3O7 (Y123). During the study, trapped magnetic field, B(t), has been increased by over a factor of 10(exp 5). Methods used to improve magnetic field trapping were principally: (1) the adoption of the Melt Texturing process to increase grain size; (2) the addition of excess Y to disperse deposits of Y2BaCuO5 (Y211) and again increase grain size; (3) irradiation with high energy particles including 1H+, 3He++, 4He++, and fission fragments; and (4) utilizing temperatures below 77 K has also been quantified as a way to increase trapped field. In addition, in our study of B(t), we have found laws governing creep, activation, temperature dependence, creep vs. current flow, etc. In the range 20 K less than or equal to T less than or equal to 65 K, and for B less than 10 Tesla, a simple empirical relationship was found: B(trap) (T2) = B(trap) (T1) ((Tc - T2)/(Tc - T1))squared where Tc is the critical temperature. The highest experimental trapped field was B(trap) = 3.96 Tesla, at 65 K. We believe this to be the highest persistent field ever produced, by any method. A two component model of the persistent currents has been developed. This accurately reproduces the data, using as parameters only the magnitude of a constant surface current, J(s), and a constant volume current J(v). The model successfully predicts B(t) (xyz) for the case of maximum trapped field, for all samples observed. It has also been extended to describe the unsaturated case either zero field cooled, or field cooled. Loss of strap with time has been studied for the critical state (Bt,max), and non critical state (Bt less than Bt,max), for times from a few minutes to a few months, for unirradiated material, for irradiation by 1H+, 3He++, 4He++, high z projectiles, and neutrons, and for all materials used in the overall study. We conclude that: (1) multi Tesla trapped fields are attained; (2) fields over 10 T are achievable; (3) creep is not a large problem; (4) application is feasible to motors, generators, magnets for particle beam optics, separators, levitating bearings, energy storage, shielding, and transportation.

Cardiovascular disease risk scores in the current practice: which to use in rheumatoid arthritis?

PubMed

Purcarea, A; Sovaila, S; Gheorghe, A; Udrea, G; Stoica, V

2014-01-01

Cardiovascular disease (CVD) is the highest prevalence disease in the general population (GP) and it accounts for 20 million deaths worldwide each year. Its prevalence is even higher in rheumatoid arthritis. Early detection of subclinical disease is critical and the use of cardiovascular risk prediction models and calculators is widely spread. The impact of such techniques in the GP was previously studied. Despite their common background and similarities, some disagreement exists between most scores and their importance in special high-risk populations like rheumatoid arthritis (RA), having a low level of evidence. The current article aims to single out those predictive models (models) that could be most useful in the care of rheumatoid arthritis patients.

Cardiovascular disease risk scores in the current practice: which to use in rheumatoid arthritis?

PubMed Central

Purcarea, A; Sovaila, S; Gheorghe, A; Udrea, G; Stoica, V

2014-01-01

Cardiovascular disease (CVD) is the highest prevalence disease in the general population (GP) and it accounts for 20 million deaths worldwide each year. Its prevalence is even higher in rheumatoid arthritis. Early detection of subclinical disease is critical and the use of cardiovascular risk prediction models and calculators is widely spread. The impact of such techniques in the GP was previously studied. Despite their common background and similarities, some disagreement exists between most scores and their importance in special high-risk populations like rheumatoid arthritis (RA), having a low level of evidence. The current article aims to single out those predictive models (models) that could be most useful in the care of rheumatoid arthritis patients. PMID:25713603

Crayfishes (Decapoda : Cambaridae) of Oklahoma: identification, distributions, and natural history.

PubMed

Morehouse, Reid L; Tobler, Michael

2013-01-01

We furnish an updated crayfish species list for the state of Oklahoma (United States of America), including an updated and illustrated dichotomous key. In addition, we include species accounts that summarize general characteristics, life coloration, similar species, distribution and habitat, life history, and syntopic species. Current and potential distributions were analyzed using ecological niche models to provide a critical resource for the identification of areas with conservation priorities and potential susceptibility to invasive species. Currently, Oklahoma harbors 30 species of crayfish, two of which were recently discovered. Eastern Oklahoma has the highest species diversity, as this area represents the western distribution extent for several species. The work herein provides baseline data for future work on crayfish biology and conservation in Oklahoma and surrounding states.

Assessment of Environmental Flows under Human Intervention and Climate Change Conditions in a Mediterranean Watershed

NASA Astrophysics Data System (ADS)

Yilmaz, M. T.; Alp, E.; Aras, M.; Özaltın, A. M.; Sarıcan, Y.; Afsar, M.; Bulut, B.; Ersoy, E. N.; Karasu, İ. G.; Onen, A.

2017-12-01

Allocation of the river flow for ecosystems is very critical for sustainable management of ecosystems containing aquatic habitats in need of more water than other environments. Availability and allocation of water over such locations becomes more stressed as a result of the influence of human interventions (e.g., increased water use for irrigation) and the expected change in climate. This study investigates the current and future (until 2100) low-flow requirements over 10 subcatchments in a Mediterranean Watershed, in Turkey, using Tennant and hydrological low-flow methods. The future river flows are estimated using HBV model forced by climate projections obtained by HADGEM2, MPI-ESM-MR, and CNRM-CM5.1 models coupled with RegCM4.3 under RCP 4.5 and RCP 8.5 emission scenarios. Critical flows (i.e., Q10, Q25, Q50) are calculated using the best fit to commonly used distributions for the river flow data, while the decision between the selection of Q10, Q25, Q50 critical levels are made depending on the level of human interference made over the catchment. Total three low-flow requirement estimations are obtained over each subcatchment using the Tennant (two estimates for the low and high flow seasons for environmentally good conditions) and the hydrological low-flow methods. The highest estimate among these three methods is selected as the low-flow requirement of the subcatchment. The river flows over these 10 subcatchments range between 197hm3 and 1534hm3 while the drainage areas changing between 936 and 4505 km2. The final low-flow estimation (i.e., the highest among the three estimate) for the current conditions range between 94 hm3 and 715 hm3. The low-flow projection values between 2075 and 2099 are on average 39% lower than the 2016 values, while the steepest decline is expected between 2050 and 2074. The low flow and high flow season Tennant estimates dropped 22-25% while the hydrological method low-flow estimates dropped 32% from 2016 to 2075-2099 average, where Tennant estimates are sensitive to the precipitation projections while hydrological flow estimates are sensitive to the degree that the subcatchment flows are regulated/intervened. On the other hand, the combined low-flow estimate, the highest of three methods, dropped around 39%, reflecting combined impact of human intervention and climate change.

Unusually high critical current of clean P-doped BaFe2As2 single crystalline thin film

NASA Astrophysics Data System (ADS)

Kurth, F.; Tarantini, C.; Grinenko, V.; Hänisch, J.; Jaroszynski, J.; Reich, E.; Mori, Y.; Sakagami, A.; Kawaguchi, T.; Engelmann, J.; Schultz, L.; Holzapfel, B.; Ikuta, H.; Hühne, R.; Iida, K.

2015-02-01

Microstructurally clean, isovalently P-doped BaFe2As2 (Ba-122) single crystalline thin films have been prepared on MgO (001) substrates by molecular beam epitaxy. These films show a superconducting transition temperature (Tc) of over 30 K although P content is around 0.22, which is lower than the optimal one for single crystals (i.e., 0.33). The enhanced Tc at this doping level is attributed to the in-plane tensile strain. The strained film shows high transport self-field critical current densities (Jc) of over 6 MA/cm2 at 4.2 K, which are among the highest for Fe based superconductors (FeSCs). In-field Jc exceeds 0.1 MA/cm2 at μ 0 H = 35 T for H ‖ a b and μ 0 H = 18 T for H ‖ c at 4.2 K, respectively, in spite of moderate upper critical fields compared to other FeSCs with similar Tc. Structural investigations reveal no defects or misoriented grains pointing to strong pinning centers. We relate this unexpected high Jc to a strong enhancement of the vortex core energy at optimal Tc, driven by in-plane strain and doping. These unusually high Jc make P-doped Ba-122 very favorable for high-field magnet applications.

Lung transplantation in the most critically-III: forging ahead.

PubMed

Mulvihill, Michael S; Hartwig, Matthew G; Daneshmand, Mani A

2017-09-01

Lung transplantation is the gold standard therapy for patients with end-stage lung disease. The use of the lung allocation score (LAS) has permitted improved allocation of scarce pulmonary allografts. Recently, Crawford et al. examined the experience in the United States in lung transplantation in candidates with the highest LAS, demonstrating that outcomes for candidates with the highest LAS scores have improved significantly. This editorial places these data in the broader context of thoracic transplantation, and highlights the critical need for ongoing examination of this critically-ill patient population.

Review of teaching methods and critical thinking skills.

PubMed

Kowalczyk, Nina

2011-01-01

Critical information is needed to inform radiation science educators regarding successful critical thinking educational strategies. From an evidence-based research perspective, systematic reviews are identified as the most current and highest level of evidence. Analysis at this high level is crucial in analyzing those teaching methods most appropriate to the development of critical thinking skills. To conduct a systematic literature review to identify teaching methods that demonstrate a positive effect on the development of students' critical thinking skills and to identify how these teaching strategies can best translate to radiologic science educational programs. A comprehensive literature search was conducted resulting in an assessment of 59 full reports. Nineteen of the 59 reports met inclusion criteria and were reviewed based on the level of evidence presented. Inclusion criteria included studies conducted in the past 10 years on sample sizes of 20 or more individuals demonstrating use of specific teaching interventions for 5 to 36 months in postsecondary health-related educational programs. The majority of the research focused on problem-based learning (PBL) requiring standardized small-group activities. Six of the 19 studies focused on PBL and demonstrated significant differences in student critical thinking scores. PBL, as described in the nursing literature, is an effective teaching method that should be used in radiation science education. ©2011 by the American Society of Radiologic Technologists.

Analysis of limiting information characteristics of quantum-cryptography protocols

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

Sych, D V; Grishanin, Boris A; Zadkov, Viktor N

2005-01-31

The problem of increasing the critical error rate of quantum-cryptography protocols by varying a set of letters in a quantum alphabet for space of a fixed dimensionality is studied. Quantum alphabets forming regular polyhedra on the Bloch sphere and the continual alphabet equally including all the quantum states are considered. It is shown that, in the absence of basis reconciliation, a protocol with the tetrahedral alphabet has the highest critical error rate among the protocols considered, while after the basis reconciliation, a protocol with the continual alphabet possesses the highest critical error rate. (quantum optics and quantum computation)

Space Shuttle Main Engine (SSME) Evolution

NASA Technical Reports Server (NTRS)

Worlund, Len A.; Hastings, J. H.; McCool, Alex (Technical Monitor)

2001-01-01

The SSME when developed in the 1970's was a technological leap in space launch propulsion system design. The engine has safely supported the space shuttle for the last two decades and will be required for at least another decade to support human space flight to the international space station. This paper discusses the continued improvements and maturing of the system to its current state and future considerations for its critical role in the nations space program. Discussed are the initiatives of the late 1980's, which lead to three major upgrades through the 1990's. The current capabilities of the propulsion system are defined in the areas of highest programmatic importance: ascent risk, in-flight abort thrust, reusability, and operability. Future initiatives for improved shuttle safety, the paramount priority of the Space Shuttle program are discussed.

Outcome of Pediatric Critical Care Medicine Abstracts Presented at North American Academic National Meetings.

PubMed

Basu, Sonali; Pollack, Murray M

2017-05-05

Pediatric critical care medicine abstracts presented at North American national academic meetings have not been followed up to determine their publication outcomes. Our objective was to determine the following: 1) the proportion of these presentations that are published in peer-reviewed journals within 5 years; 2) the impact of trainee status on time to and success of publication; and 3) the quality of the research as reflected in the publishing journal's impact factor. Four years of abstracts (2007-2011) were reviewed from the American Academy of Pediatrics, Pediatric Academic Societies, and Society of Critical Care Medicine national meetings. Pediatric critical care medicine abstracts were delineated by the meeting or identified by keyword search. Data included mode of presentation, trainee status of first author, publication status within 5 years based on a PubMed search, trainee position in the journal of publication authorship list, and the impact factor of journal of publication. We evaluated 267 pediatric critical care medicine abstracts, 85-94 from each meeting. Overall, 41% were published, with the highest rate in Pediatric Academic Societies abstracts (54% Pediatric Academic Societies, 38% Society of Critical Care Medicine, and 33% American Academy of Pediatrics; p = 0.011). Mean time to publication was 22 (± 3) months and did not differ by conference or presentation mode. Journal first authorship was retained in 84%. Journal impact factor was highest in Society of Critical Care Medicine abstracts (3.38 Society of Critical Care Medicine, 2.64 Pediatric Academic Societies, and 1.92 American Academy of Pediatrics; p = 0.006). First author trainee status was not associated with publication rate, time to publication, and impact factor. A total of 100% of trainees but only 79% of nontrainees who published retained first authorship. Less than half of pediatric critical care medicine research abstracts presented at North American national academic meetings culminate in articles. Pediatric Academic Societies had the highest publication success rate, and Society of Critical Care Medicine abstracts were published in journals with the highest impact factors. All trainees who were first authors retained that status in the journal publications.

So Much More than Just a List: Exploring the Nature of Critical Questioning in Undergraduate Sciences

ERIC Educational Resources Information Center

Pedrosa-de-Jesus, Helena; Moreira, Aurora; Lopes, Betina; Watts, Mike

2014-01-01

Background: Critical thinking is one of the very highest orders of cognitive abilities and a key competency in higher education. Asking questions is an important component of rich learning experiences, structurally embedded in the operations of critical thinking. Our clear sense is that critical thinking and, within that, critical questioning, is…

Temperature and Microstructural Effects on the Superconducting Properties of Niobium Thin Films

DOE PAGES

Beebe, Melissa R.; Valente-Feliciano, Anne -Marie; Beringer, Douglas B.; ...

2016-11-23

Here, superconducting thin films have a wide range of dc and RF applications, from detectors to superconducting radio frequency. Amongst the most used materials, niobium (Nb) has the highest critical temperature (TC) and highest lower critical field (HC1) of the elemental superconductors and can be deposited on a variety of substrates, making Nb thin films very appealing for such applications. Here, we present temperature-dependent dc studies on the critical temperature and critical fields of Nb thin films grown on copper and r-plane sapphire surfaces. Additionally, we correlate the dc superconducting properties of these films with their microstructure, which allows formore » the possibility of tailoring future films for a specific application.« less

A critical care network pressure ulcer prevention quality improvement project.

PubMed

McBride, Joanna; Richardson, Annette

2015-03-30

Pressure ulcer prevention is an important safety issue, often underrated and an extremely painful event harming patients. Critically ill patients are one of the highest risk groups in hospital. The impact of pressure ulcers are wide ranging, and they can result in increased critical care and the hospital length of stay, significant interference with functional recovery and rehabilitation and increase cost. This quality improvement project had four aims: (1) to establish a critical care network pressure ulcer prevention group; (2) to establish baseline pressure ulcer prevention practices; (3) to measure, compare and monitor pressure ulcers prevalence; (4) to develop network pressure ulcer prevention standards. The approach used to improve quality included strong critical care nursing leadership to develop a cross-organisational pressure ulcer prevention group and a benchmarking exercise of current practices across a well-established critical care Network in the North of England. The National Safety Thermometer tool was used to measure pressure ulcer prevalence in 23 critical care units, and best available evidence, local consensus and another Critical Care Networks' bundle of interventions were used to develop a local pressure ulcer prevention standards document. The aims of the quality improvement project were achieved. This project was driven by successful leadership and had an agreed common goal. The National Safety Thermometer tool was an innovative approach to measure and compare pressure ulcer prevalence rates at a regional level. A limitation was the exclusion of moisture lesions. The project showed excellent engagement and collaborate working in the quest to prevent pressure ulcers from many critical care nurses with the North of England Critical Care Network. A concise set of Network standards was developed for use in conjunction with local guidelines to enhance pressure ulcer prevention. © 2015 British Association of Critical Care Nurses.

Observing terrestrial ecosystems and the carbon cycle from space

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

Schimel, David; Pavlick, Ryan; Fisher, Joshua B.

2015-02-06

Modeled terrestrial ecosystem and carbon cycle feedbacks contribute substantial uncertainty to projections of future climate. The limitations of current observing networks contribute to this uncertainty. Here we present a current climatology of global model predictions and observations for photosynthesis, biomass, plant diversity and plant functional diversity. Carbon cycle tipping points occur in terrestrial regions where fluxes or stocks are largest, and where biological variability is highest, the tropics and Arctic/Boreal zones. Global observations are predominately in the mid-latitudes and are sparse in high and low latitude ecosystems. Observing and forecasting ecosystem change requires sustained observations of sufficient density in timemore » and space in critical regions. Using data and theory available now, we can develop a strategy to detect and forecast terrestrial carbon cycle-climate interactions, by combining in situ and remote techniques.« less

Atomistic modeling trap-assisted tunneling in hole tunnel field effect transistors

NASA Astrophysics Data System (ADS)

Long, Pengyu; Huang, Jun Z.; Povolotskyi, Michael; Sarangapani, Prasad; Valencia-Zapata, Gustavo A.; Kubis, Tillmann; Rodwell, Mark J. W.; Klimeck, Gerhard

2018-05-01

Tunnel Field Effect Transistors (FETs) have the potential to achieve steep Subthreshold Swing (S.S.) below 60 mV/dec, but their S.S. could be limited by trap-assisted tunneling (TAT) due to interface traps. In this paper, the effect of trap energy and location on OFF-current (IOFF) of tunnel FETs is evaluated systematically using an atomistic trap level representation in a full quantum transport simulation. Trap energy levels close to band edges cause the highest leakage. Wave function penetration into the surrounding oxide increases the TAT current. To estimate the effects of multiple traps, we assume that the traps themselves do not interact with each other and as a whole do not modify the electrostatic potential dramatically. Within that model limitation, this numerical metrology study points to the critical importance of TAT in the IOFF in tunnel FETs. The model shows that for Dit higher than 1012/(cm2 eV) IO F F is critically increased with a degraded IO N/IO F F ratio of the tunnel FET. In order to have an IO N/IO F F ratio higher than 104, the acceptable Dit near Ev should be controlled to no larger than 1012/(cm2 eV) .

Solution spinning of a high-? oxide superconductor: the effect of poly(vinyl alcohol) spinning medium on the critical current density of melt-processed ? superconducting filaments

NASA Astrophysics Data System (ADS)

Tomita, Hisayo; Sunohara, Makoto; Goto, Tomoko; Takahashi, Kiyohisa

1996-12-01

The precursor 0953-2048/9/12/014/img9 filament was prepared by solution spinning through a homogeneous aqueous poly(vinyl alcohol) (PVA) solution of Y, Ba and Cu acetates. The solution spinning was successfully performed using PVA with degrees of polymerization (DP) of 1700 and 2450 and a degree of saponification of 85 mol%. The as-drawn filament was heated to remove volatile components and partially melted to generate a superconducting phase. The effects of the DP of PVA and a content of mixed acetates in the precursor filament on the critical current density 0953-2048/9/12/014/img10 of the melt-processed filament were examined. The higher 0953-2048/9/12/014/img11 was obtained for the filament spun from PVA solution of higher DP and lower acetate content. The highest 0953-2048/9/12/014/img11 value of 0953-2048/9/12/014/img13 at 77 K and 0 T was achieved for the filament spun from the DP 2450 PVA with an acetate to PVA ratio of two.

Physician Burnout: Improving Treatment Efficacy with Virtual Reality.

PubMed

Wiederhold, Brenda K; Riva, Giuseppe; Gaggioli, Andrea; Wiederhold, Mark D

2016-01-01

Creating a significant negative impact on both their quality of life and the quality of patient care with an evident economical burden for the healthcare system, there is a growing concern over physician burnout. The range of interventions and treatments that have been used to address this problem, however, appear quite fragmented and lack compelling efficacy. We describe the main factors known to contribute to the development of physician burnout as well as currently available treatments. Studies seem to indicate that both specialisation area as well as personality traits may contribute to the manifestation. The highest risk specialties appear to be critical care physicians, emergency physicians, oncologists and internal medicine physicians, while the highest risk personality attributes are high neuroticism, low agreeableness, introversion, and negative affectivity. In addition, being exceedingly enthusiastic about one's work and having high aspirations at work, with an idealistic approach, also serve as factors which contribute to increased risk of burnout, and in particular for those who are new to the occupation.

Electron-band theory inspired design of magnesium-precious metal bulk metallic glasses with high thermal stability and extended ductility.

PubMed

Laws, Kevin J; Shamlaye, Karl F; Granata, Davide; Koloadin, Leah S; Löffler, Jörg F

2017-06-13

Magnesium-based bulk metallic glasses (BMGs) exhibit high specific strengths and excellent glass-forming ability compared to other metallic systems, making them suitable candidates for next-generation materials. However, current Mg-based BMGs tend to exhibit low thermal stability and are prone to structural relaxation and brittle failure. This study presents a range of new magnesium-precious metal-based BMGs from the ternary Mg-Ag-Ca, Mg-Ag-Yb, Mg-Pd-Ca and Mg-Pd-Yb alloy systems with Mg content greater than 67 at.%. These alloys were designed for high ductility by utilising atomic bond-band theory and a topological efficient atomic packing model. BMGs from the Mg-Pd-Ca alloy system exhibit high glass-forming ability with critical casting sizes of up to 3 mm in diameter, the highest glass transition temperatures (>200 °C) of any reported Mg-based BMG to date, and sustained compressive ductility. Alloys from the Mg-Pd-Yb family exhibit critical casting sizes of up to 4 mm in diameter, and the highest compressive plastic (1.59%) and total (3.78%) strain to failure of any so far reported Mg-based glass. The methods and theoretical approaches presented here demonstrate a significant step forward in the ongoing development of this extraordinary class of materials.

Temperature-dependent electrochemical heat generation in a commercial lithium-ion battery

NASA Astrophysics Data System (ADS)

Bandhauer, Todd M.; Garimella, Srinivas; Fuller, Thomas F.

2014-02-01

Lithium-ion batteries suffer from inherent thermal limitations (i.e., capacity fade and thermal runaway); thus, it is critical to understand heat generation experienced in the batteries under normal operation. In the current study, reversible and irreversible electrochemical heat generation rates were measured experimentally on a small commercially available C/LiFePO4 lithium-ion battery designed for high-rate applications. The battery was tested over a wide range of temperatures (10-60 °C) and discharge and charge rates (∼C/4-5C) to elucidate their effects. Two samples were tested in a specially designed wind tunnel to maintain constant battery surface temperature within a maximum variation of ±0.88 °C. A data normalization technique was employed to account for the observed capacity fade, which was largest at the highest rates. The heat rate was shown to increase with both increasing rate and decreasing temperature, and the reversible heat rate was shown to be significant even at the highest rate and temperature (7.4% at 5C and 55 °C). Results from cycling the battery using a dynamic power profile also showed that constant-current data predict the dynamic performance data well. In addition, the reversible heat rate in the dynamic simulation was shown to be significant, especially for charge-depleting HEV applications.

Critical temperature: A quantitative method of assessing cold tolerance

Treesearch

D.H. DeHayes; M.W., Jr. Williams

1989-01-01

Critical temperature (Tc), defined as the highest temperature at which freezing injury to plant tissues can be detected, provides a biologically meaningful and statistically defined assessment of the relative cold tolerance of plant tissues. A method is described for calculating critical temperatures in laboratory freezing studies that use...

Large pinning forces and matching effects in YBa2Cu3O7-δ thin films with Ba2Y(Nb/Ta)O6 nano-precipitates

NASA Astrophysics Data System (ADS)

Opherden, Lars; Sieger, Max; Pahlke, Patrick; Hühne, Ruben; Schultz, Ludwig; Meledin, Alexander; van Tendeloo, Gustaaf; Nast, Rainer; Holzapfel, Bernhard; Bianchetti, Marco; MacManus-Driscoll, Judith L.; Hänisch, Jens

2016-02-01

The addition of mixed double perovskite Ba2Y(Nb/Ta)O6 (BYNTO) to YBa2Cu3O7-δ (YBCO) thin films leads to a large improvement of the in-field current carrying capability. For low deposition rates, BYNTO grows as well-oriented, densely distributed nanocolumns. We achieved a pinning force density of 25 GN/m3 at 77 K at a matching field of 2.3 T, which is among the highest values reported for YBCO. The anisotropy of the critical current density shows a complex behavior whereby additional maxima are developed at field dependent angles. This is caused by a matching effect of the magnetic fields c-axis component. The exponent N of the current-voltage characteristics (inversely proportional to the creep rate S) allows the depinning mechanism to be determined. It changes from a double-kink excitation below the matching field to pinning-potential-determined creep above it.

Children’s Inferential Styles, 5-HTTLPR Genotype, and Maternal Expressed Emotion-Criticism: An Integrated Model for the Intergenerational Transmission of Depression

PubMed Central

Gibb, Brandon E.; Uhrlass, Dorothy J.; Grassia, Marie; Benas, Jessica S.; McGeary, John

2010-01-01

We tested a model for the intergenerational transmission of depression integrating specific genetic (5-HTTLPR), cognitive (inferential style), and environmental (mother depressive symptoms and expressed-emotion criticism) risk factors. Supporting the hypothesis that maternal depression is associated with elevated levels of stress in children’s lives, mothers with a history of major depressive disorder (MDD) exhibited higher depressive symptoms across a 6-month multi-wave follow-up than mothers with no depression history. In addition, partially supporting our hypothesis, levels of maternal criticism during the follow-up were significantly related to mothers’ current depressive symptoms, but not history of MDD. Finally, we found support for an integrated gene × cognition × environment model of risk. Specifically, among children with negative inferential styles regarding their self-characteristics, there was a clear dose response of 5-HTTLPR genotype moderating the relation between maternal criticism and children’s depressive symptoms, with the highest depressive symptoms during the follow-up observed among children carrying two copies of the 5-HTTLPR lower expressing alleles (S or LG) who also exhibited negative inferential styles for self-characteristics and who experienced high levels of EE-Crit. In contrast, children with positive inferential styles exhibited low depressive symptoms regardless of 5-HTTLPR genotype or level of maternal criticism. PMID:19899843

Children's inferential styles, 5-HTTLPR genotype, and maternal expressed emotion-criticism: An integrated model for the intergenerational transmission of depression.

PubMed

Gibb, Brandon E; Uhrlass, Dorothy J; Grassia, Marie; Benas, Jessica S; McGeary, John

2009-11-01

The authors tested a model for the intergenerational transmission of depression integrating specific genetic (5-HTTLPR), cognitive (inferential style), and environmental (mother depressive symptoms and expressed-emotion criticism [EE-Crit]) risk factors. Supporting the hypothesis that maternal depression is associated with elevated levels of stress in children's lives, mothers with a history of major depressive disorder (MDD) exhibited higher depressive symptoms across a 6-month multiwave follow-up than mothers with no depression history. In addition, partially supporting our hypothesis, levels of maternal criticism during the follow-up were significantly related to mothers' current depressive symptoms but not to history of MDD. Finally, the authors found support for an integrated Gene x Cognition x Environment model of risk. Specifically, among children with negative inferential styles regarding their self-characteristics, there was a clear dose response of 5-HTTLPR genotype moderating the relation between maternal criticism and children's depressive symptoms, with the highest depressive symptoms during the follow-up observed among children carrying 2 copies of the 5-HTTLPR lower expressing alleles (short [S] or long [LG]) who also exhibited negative inferential styles for self-characteristics and who experienced high levels of EE-Crit. In contrast, children with positive inferential styles exhibited low depressive symptoms regardless of 5-HTTLPR genotype or level of maternal criticism. PsycINFO Database Record 2009 APA, all rights reserved.

The accuracy and safety of fluoroscopic-guided percutaneous pedicle screws in the thoracic and lumbosacral spine in the Asian population: A CT scan analysis of 1002 screws.

PubMed

Chiu, Chee Kidd; Chan, Chris Yin Wei; Kwan, Mun Keong

2017-01-01

This study investigates the safety and accuracy of percutaneous pedicle screws placed using fluoroscopic guidance in the thoracolumbosacral spine among Asian patients. Computerized tomography scans of 128 patients who had surgery using fluoroscopic-guided percutaneous pedicle screws were selected. Medial, lateral, superior, and inferior screw perforations were classified into grade 0 (no violation), grade 1 (<2 mm perforation), grade 2 (2-4 mm perforation), and grade 3(>4 mm perforation). Anterior perforations were classified into grade 0 (no violation), grade 1 (<4 mm perforation), grade 2 (4-6 mm perforation), and grade 3(>6 mm perforation). Grade 2 and grade 3 perforation were considered as "critical" perforation. In total, 1002 percutaneous pedicle screws from 128 patients were analyzed. The mean age was 52.7 ± 16.6. There were 70 male patients and 58 female patients. The total perforation rate was 11.3% (113) with 8.4% (84) grade 1, 2.6% (26) grade 2, and 0.3% (3) grade 3 perforations. The overall "critical" perforation rate was 2.9% (29 screws) and no complications were noted. The highest perforation rates were at T4 (21.6%), T2 (19.4%), and T6 (19.2%). The total perforation rate of 11.3% with the total "critical" perforation rate of 2.9% (2.6% grade 2 and 0.3% grade 3 perforations). The highest perforation rates were found over the upper to mid-thoracic region. Fluoroscopic-guided percutaneous pedicle screws insertion among Asians has the safety and accuracy comparable to the current reported percutaneous pedicle screws and open pedicle screws techniques.

In search of critically endangered species: the current situation of two tiny salamander species in the Neotropical mountains of Mexico.

PubMed

Sandoval-Comte, Adriana; Pineda, Eduardo; Aguilar-López, José L

2012-01-01

Worldwide, one in every three species of amphibian is endangered, 39 species have gone extinct in the last 500 years and another 130 species are suspected to have gone extinct in recent decades. Of the amphibians, salamanders have the highest portion of their species in one of the risk categories, even higher than the frogs. To date there have been few studies that have used recent field data to examine the status of populations of endangered salamanders. In this study we evaluate the current situation of two tiny salamanders, Parvimolge townsendi and Thorius pennatulus, both of which are distributed at intermediate elevations in the mountains of the northern Neotropics and are considered to be critically endangered; the first has been proposed as possibly extinct. By carrying out exhaustive surveys in both historical and potentially suitable sites for these two species, we evaluated their abundance and the characteristics of their habitats, and we estimated their potential geographic distribution. We visited 22 sites, investing 672 person-hours of sampling effort in the surveys, and found 201 P. townsendi salamanders in 11 sites and only 13 T. pennatulus salamanders in 5 sites. Both species were preferentially found in cloud forest fragments that were well conserved or only moderately transformed, and some of the salamanders were found in shade coffee plantations. The potential distribution area of both species is markedly fragmented and we estimate that it has decreased by more than 48%. The results of this study highlight the importance of carrying out exhaustive, systematic field surveys to obtain accurate information about the current situation of critically endangered species, and help us better understand the crisis that amphibians are facing worldwide.

Moral distress and intention to leave: A comparison of adult and paediatric nurses by hospital setting.

PubMed

Dyo, Melissa; Kalowes, Peggy; Devries, Jessica

2016-10-01

To assess moral distress intensity and frequency in adult/paediatric nurses in critical care and non-critical care units; and explore relationships of nurse characteristics and moral distress with intention to leave. A descriptive, correlational design was used to administer an online survey using the Moral Distress Scale to nurses across multiple settings. Intensity and frequency of moral distress and intention to leave current position. The survey response rate was 43% (n=426/1000). Critical care nurses had the highest levels of moral distress intensity and frequency, compared to non-critical care specialties (M=2.5±0.19, p=0.005 for intensity and M=1.6±0.11, p<0.001 for frequency). Moral distress frequency showed a positive relationship with intention to leave a position of employment. Each unit increase in moral distress frequency doubled the odds of intention to leave when adjusting for age, gender, ethnicity and specialty area (p=0.003). Hispanic nurses had significantly higher levels of moral distress intensity (p=0.01). Moral distress is a complex phenomenon requiring further study, particularly with regard to the role of ethnic and cultural differences on perceptions of moral distress. Copyright © 2016 Elsevier Ltd. All rights reserved.

Complete Fabrication of a Traversable 3 µm Thick NbN Film Superconducting Coil with Cu plated layer of 42m in Length in a Spiral Three-Storied Trench Engraved in a Si Wafer of 76.2 mm in Diameter Formed by MEMS Technology for a Compact SMES with High Energy Storage Volume Density

NASA Astrophysics Data System (ADS)

Suzuki, Yasuhiro; Iguchi, Nobuhiro; Adachi, Kazuhiro; Ichiki, Akihisa; Hioki, Tatsumi; Hsu, Che-Wei; Sato, Ryoto; Kumagai, Shinya; Sasaki, Minoru; Noh, Joo-Hyong; Sakurahara, Yuuske; Okabe, Kyohei; Takai, Osamu; Honma, Hideo; Watanabe, Hideo; Sakoda, Hitoshi; Sasagawa, Hiroaki; Doy, Hideyuki; Zhou, Shuliang; Hori, H.; Nishikawa, Shigeaki; Nozaki, Toshihiro; Sugimoto, Noriaki; Motohiro, Tomoyoshi

2017-09-01

Based on the concept of a novel approach to make a compact SMES unit composed of a stack of Si wafers using MEMS process proposed previously, a complete fabrication of a traversable 3 µam thick NbN film superconducting coil lined with Cu plated layer of 42m in length in a spiral three-storied trench engraved in and extended over a whole Si-wafer of 76.2 mm in diameter was attained for the first time. With decrease in temperature, the DC resistivity showed a metallic decrease indicating the current pass was in the Cu plated layer and then made a sudden fall to residual contact resistance indicating the shift of current pass from the Cu plated layer to the NbN film at the critical temperature Tc of 15.5K by superconducting transition. The temperature dependence of I-V curve showed the increase in the critical current with decrease in the temperature and the highest critical current measured was 220 mA at 4K which is five times as large as that obtained in the test fabrication as the experimental proof of concept presented in the previous report. This completion of a one wafer superconducting NbN coil is an indispensable step for the next proof of concept of fabrication of series-connected two wafer coils via superconductive joint which will read to series connected 600 wafer coils finally, and for replacement of NbN by high Tc superconductor such as YBa2Cu3O7-x for operation under the cold energy of liquid hydrogen or liquid nitrogen.

Particle astrophysics

NASA Technical Reports Server (NTRS)

Sadoulet, Bernard; Cronin, James; Aprile, Elena; Barish, Barry C.; Beier, Eugene W.; Brandenberger, Robert; Cabrera, Blas; Caldwell, David; Cassiday, George; Cline, David B.

1991-01-01

The following scientific areas are reviewed: (1) cosmology and particle physics (particle physics and the early universe, dark matter, and other relics); (2) stellar physics and particles (solar neutrinos, supernovae, and unconventional particle physics); (3) high energy gamma ray and neutrino astronomy; (4) cosmic rays (space and ground observations). Highest scientific priorities for the next decade include implementation of the current program, new initiatives, and longer-term programs. Essential technological developments, such as cryogenic detectors of particles, new solar neutrino techniques, and new extensive air shower detectors, are discussed. Also a certain number of institutional issues (the funding of particle astrophysics, recommended funding mechanisms, recommended facilities, international collaborations, and education and technology) which will become critical in the coming decade are presented.

Response to Bodin and Grote regarding postdoctoral recruitment in clinical neuropsychology.

PubMed

Nelson, Aaron; Bilder, Robert M; O'Connor, Margaret; Brandt, Jason; Weintraub, Sandra; Bauer, Russell M

2016-07-01

Bodin and Grote convey their opinion that the field of clinical neuropsychology would be best served by a match system for recruitment into postdoctoral training. We critically review their arguments and offer an alternative point of view. Our view considers the current state of the match system in neuropsychology, incorporates comparisons with other disciplines that rely on a match system, and addresses the role of postdoctoral training and the specialization that takes shape at this level. We make recommendations aimed at promoting greater unity among postdoctoral training programs with the goal of focusing leadership efforts on advancing our shared mission of providing the highest quality training in clinical neuropsychology.

Distractions during critical phases of anaesthesia for caesarean section: an observational study.

PubMed

Jenkins, A; Wilkinson, J V; Akeroyd, M A; Broom, M A

2015-05-01

Aviation's 'sterile cockpit' rule holds that distractions on the flight deck should be kept at a minimum during critical phases of flight. To assess current practice at comparable points during obstetric regional anaesthesia, we measured ambient noise and distracting events during 30 caesarean sections in three phases: during establishment of regional anaesthesia; during testing of regional blockade; and after delivery of the fetal head. Mean (SD) noise levels were 62.5 (3.9) dB during establishment of blockade, 63.9 (4.1) dB during testing and 66.8 (5.0) dB after delivery (p < 0.001). The median rates of sudden, loud (> 70 dB) noises, non-clinical conversations and numbers of staff present in the operating theatre increased during each of the three phases. Conversely, entrances into, and exits from, theatre per minute were highest during establishment of regional anaesthesia and decreased over the subsequent two time periods (p < 0.001). © 2014 The Association of Anaesthetists of Great Britain and Ireland.

World Health Organization Ranking of Antimicrobials According to Their Importance in Human Medicine: A Critical Step for Developing Risk Management Strategies to Control Antimicrobial Resistance From Food Animal Production.

PubMed

Collignon, Peter C; Conly, John M; Andremont, Antoine; McEwen, Scott A; Aidara-Kane, Awa; Agerso, Yvonne; Andremont, Antoine; Collignon, Peter; Conly, John; Dang Ninh, Tran; Donado-Godoy, Pilar; Fedorka-Cray, Paula; Fernandez, Heriberto; Galas, Marcelo; Irwin, Rebecca; Karp, Beth; Matar, Gassan; McDermott, Patrick; McEwen, Scott; Mitema, Eric; Reid-Smith, Richard; Scott, H Morgan; Singh, Ruby; DeWaal, Caroline Smith; Stelling, John; Toleman, Mark; Watanabe, Haruo; Woo, Gun-Jo

2016-10-15

Antimicrobial use in food animals selects for antimicrobial resistance in bacteria, which can spread to people. Reducing use of antimicrobials-particularly those deemed to be critically important for human medicine-in food production animals continues to be an important step for preserving the benefits of these antimicrobials for people. The World Health Organization ranking of antimicrobials according to their relative importance in human medicine was recently updated. Antimicrobials considered the highest priority among the critically important antimicrobials were quinolones, third- and fourth-generation cephalosporins, macrolides and ketolides, and glycopeptides. The updated ranking allows stakeholders in the agriculture sector and regulatory agencies to focus risk management efforts on drugs used in food animals that are the most important to human medicine. In particular, the current large-scale use of fluoroquinolones, macrolides, and third-generation cephalosporins and any potential use of glycopeptides and carbapenems need to be addressed urgently. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Critical current density of high-quality Bi2Sr2Ca2Cu3Ox thin films prepared by metalorganic chemical-vapor deposition

NASA Astrophysics Data System (ADS)

Yamasaki, H.; Endo, K.; Nakagawa, Y.; Umeda, M.; Kosaka, S.; Misawa, S.; Yoshida, S.; Kajimura, K.

1992-10-01

Critical current densities Jc were measured in as-deposited, c-axis-oriented Bi2Sr2Ca2Cu3Ox thin films with Tc values as high as 97 K, which were prepared by metalorganic chemical-vapor deposition. These films showed high Jc (≳109 A/m2) at 77.3 K in high magnetic fields (≥1 T, H∥a-b plane). The best values are 3.3×109 A/m2 at 1 T and 9.1×108 A/m2 at 8 T, which are the highest Jc for Bi-oxide thin films among those reported so far. There were no signs of weak links in the Jc(H) behavior, and the surface morphology examined by scanning electron microscopy showed no apparent grain boundaries. The values of Jc decreased sharply when the applied field deviated from the a-b plane, and went to zero at the angles where the field component in the c direction is nearly equal to the irreversibility field Hc2* parallel to the c axis. The angular dependence of Jc of these films is most reasonably explained by the theory of intrinsic pinning.

Applying Risk Prediction Models to Optimize Lung Cancer Screening: Current Knowledge, Challenges, and Future Directions.

PubMed

Sakoda, Lori C; Henderson, Louise M; Caverly, Tanner J; Wernli, Karen J; Katki, Hormuzd A

2017-12-01

Risk prediction models may be useful for facilitating effective and high-quality decision-making at critical steps in the lung cancer screening process. This review provides a current overview of published lung cancer risk prediction models and their applications to lung cancer screening and highlights both challenges and strategies for improving their predictive performance and use in clinical practice. Since the 2011 publication of the National Lung Screening Trial results, numerous prediction models have been proposed to estimate the probability of developing or dying from lung cancer or the probability that a pulmonary nodule is malignant. Respective models appear to exhibit high discriminatory accuracy in identifying individuals at highest risk of lung cancer or differentiating malignant from benign pulmonary nodules. However, validation and critical comparison of the performance of these models in independent populations are limited. Little is also known about the extent to which risk prediction models are being applied in clinical practice and influencing decision-making processes and outcomes related to lung cancer screening. Current evidence is insufficient to determine which lung cancer risk prediction models are most clinically useful and how to best implement their use to optimize screening effectiveness and quality. To address these knowledge gaps, future research should be directed toward validating and enhancing existing risk prediction models for lung cancer and evaluating the application of model-based risk calculators and its corresponding impact on screening processes and outcomes.

The role of silver in the processing and properties of Bi-2212

NASA Technical Reports Server (NTRS)

Lang, TH.; Heeb, B.; Buhl, D.; Gauckler, L. J.

1995-01-01

The influence of the silver content and the oxygen partial pressure on the solidus temperature and the weight loss during melting of Bi2Sr2Ca1Cu2O(x) has been examined by means of DTA and TGA. By decreasing the oxygen partial pressure the solidus is lowered (e.g. del T = 59 C by decreasing pO2 from 1 atm to 0.001 atm) and the weight loss is increased. The addition of silver causes two effects: (1) the solidus is further decreased (e.g. 2 wt% Ag lower T (solidus) by up to 25 C, depending on the oxygen partial pressure); and (2) the weight loss during melting is reduced. Thick films (10-20 micron in thickness) with 0 and 5 wt% silver and bulk samples with) and 2.7 wt% silver were melt processed in flowing oxygen on a silver substrate in the DTA, allowing the observation of the melting process and a good temperature control. The critical current densities are vigorously dependent on the maximum processing temperature. The highest j(sub c) in thick films (8000 A/sq cm at 77 K, O T) was reached by melting 7 C above the solidus temperature. The silver addition shows no significant effect on the processing parameters or the superconducting properties. The highest j(sub c) for bulk samples (1 mm in thickness) was obtained by partial melting at 900 C or 880 C, depending on the silver content of the powder (0 or 2.7 wt%). The j(sub c) of the samples is slightly enhanced from 1800 A/sq cm (at 77 K, O T) to 2000 A/sq cm by the silver addition. To be able to reach at least 80% of the maximum critical current density, the temperature has to be controlled in a window of 5 C for thick films and 17 C for bulk samples.

Evaluation of critical current density and residual resistance ratio limits in powder in tube Nb 3Sn conductors

DOE PAGES

Segal, Christopher; Tarantini, Chiara; Sung, Zu Hawn; ...

2016-06-10

High critical current density (Jc) Nb 3Sn A15 multifilamentary wires require a large volume fraction of small grain, superconducting A15 phase, as well as Cu stabilizer with high Residual Resistance Ratio (RRR) to provide electromagnetic stabilization and protection. In Powder-in-Tube (PIT) wires the unreacted Nb7.5wt.%Ta outer layer of the tubular filaments acts as a diffusion barrier and protects the interfilamentary Cu stabilizer from Sn contamination. A high RRR requirement generally imposes a restricted A15 reaction heat treatment (HT) to prevent localized full reaction of the filament that could allow Sn to reach the Cu. In this paper we investigate recentmore » high quality PIT wires that achieve a J c(12 T, 4.2 K) up to ~2500 A/mm -2 and find that the minimum diffusion barrier thickness decreases as the filament aspect ratio increases from ~1 in the inner rings of filaments to 1.3 in the outer filament rings. We found that just 2-3 diffusion barrier breaches can degrade RRR from 300 to 150 or less. Using progressive etching of the Cu we also found that the RRR degradation is localized near the external filaments where deformation is highest. Consequently minimizing filament distortion during strand fabrication is important for reducing RRR degradation. The additional challenge of developing the highest possible J c must be addressed by forming the maximum fraction of high J c small-grain (SG) A15 and minimizing low J c large-grain (LG) A15 morphologies. Finally, in one wire we found that 15% of the filaments had a significantly enhanced SG/LG A15 ratio and no residual A15 in the core, a feature that opens a path to substantial J c improvement.« less

The evolution of epilepsy surgery between 1991 and 2011 in nine major epilepsy centers across the United States, Germany, and Australia

PubMed Central

Jehi, Lara; Friedman, Daniel; Carlson, Chad; Cascino, Gregory; Dewar, Sandra; Elger, Christian; Engel, Jerome; Knowlton, Robert; Kuzniecky, Ruben; McIntosh, Anne; O’Brien, Terence J.; Spencer, Dennis; Sperling, Michael R.; Worrell, Gregory; Bingaman, Bill; Gonzalez-Martinez, Jorge; Doyle, Werner; French, Jacqueline

2016-01-01

Summary Objective Epilepsy surgery is the most effective treatment for select patients with drug-resistant epilepsy. In this article, we aim to provide an accurate understanding of the current epidemiologic characteristics of this intervention, as this knowledge is critical for guiding educational, academic, and resource priorities. Methods We profile the practice of epilepsy surgery between 1991 and 2011 in nine major epilepsy surgery centers in the United States, Germany, and Australia. Clinical, imaging, surgical, and histopathologic data were derived from the surgical databases at various centers. Results Although five of the centers performed their highest number of surgeries for mesial temporal sclerosis (MTS) in 1991, and three had their highest number of MTS surgeries in 2001, only one center achieved its peak number of MTS surgeries in 2011. The most productive year for MTS surgeries varied then by center; overall, the nine centers surveyed performed 48% (95% confidence interval [CI] −27.3% to −67.4%) fewer such surgeries in 2011 compared to either 1991 or 2001, whichever was higher. There was a parallel increase in the performance of surgery for nonlesional epilepsy. Further analysis of 5/9 centers showed a yearly increase of 0.6 ± 0.07% in the performance of invasive electroencephalography (EEG) without subsequent resections. Overall, although MTS was the main surgical substrate in 1991 and 2001 (proportion of total surgeries in study centers ranging from 33.3% to 70.2%); it occupied only 33.6% of all resections in 2011 in the context of an overall stable total surgical volume. Significance These findings highlight the major aspects of the evolution of epilepsy surgery across the past two decades in a sample of well-established epilepsy surgery centers, and the critical current challenges of this treatment option in addressing complex epilepsy cases requiring detailed evaluations. Possible causes and implications of these findings are discussed. PMID:26250432

Self-criticism and social phobia in the US national comorbidity survey.

PubMed

Cox, Brian J; Fleet, Claire; Stein, Murray B

2004-10-15

This study sought to extend findings from a preliminary clinical investigation [J. Affect. Disord. 57 (2000) 223] by examining relations between the personality dimension of self-criticism and diagnostic prevalence of social phobia in a large nationally representative sample. Participants were from the national comorbidity survey Part II [n=5877; Arch. Gen. Psychiatry 51 (1994) 8]. Psychiatric diagnoses were made using a modified version of the composite international psychiatric interview. Personality dimensions and distress were assessed using brief self-report measures with strong psychometric properties. Self-criticism was elevated in NCS respondents with a diagnosis of social phobia, even in cases of only past history of social phobia (i.e. >1 year ago), compared to individuals with no psychiatric disorder. The highest levels of self-criticism were reported by people with the complex subtype of social phobia, both with and without comorbid major depression. These levels were significantly greater compared to those observed in another anxiety disorder (panic disorder), the pure speaking subtype of social phobia, and cases of major depression alone. In a regression analysis that controlled for current emotional distress, the broad personality trait of neuroticism, and lifetime histories of mood, anxiety, and substance use disorders, self-criticism remained significantly associated with lifetime prevalence of social phobia. The cross-sectional design of the study does not permit causal inferences. Findings from this general population mental health survey demonstrated that self-criticism is robustly associated with social phobia. It may represent an important core psychological process in the complex subtype of this anxiety disorder.

The upper critical field of filamentary Nb3Sn conductors

NASA Astrophysics Data System (ADS)

Godeke, A.; Jewell, M. C.; Fischer, C. M.; Squitieri, A. A.; Lee, P. J.; Larbalestier, D. C.

2005-05-01

We have examined the upper critical field of a large and representative set of present multifilamentary Nb3Sn wires and one bulk sample over a temperature range from 1.4 K up to the zero-field critical temperature. Since all present wires use a solid-state diffusion reaction to form the A15 layers, inhomogeneities with respect to Sn content are inevitable, in contrast to some previously studied homogeneous samples. Our study emphasizes the effects that these inevitable inhomogeneities have on the field-temperature phase boundary. The property inhomogeneities are extracted from field-dependent resistive transitions which we find broaden with increasing inhomogeneity. The upper 90%-99% of the transitions clearly separates alloyed and binary wires but a pure, Cu-free binary bulk sample also exhibits a zero-temperature critical field that is comparable to the ternary wires. The highest μ0Hc2 detected in the ternary wires are remarkably constant: The highest zero-temperature upper critical fields and zero-field critical temperatures fall within 29.5±0.3 and 17.8±0.3K, respectively, independent of the wire layout. The complete field-temperature phase boundary can be described very well with the relatively simple Maki-DeGennes model using a two-parameter fit, independent of composition, strain state, sample layout, or applied critical state criterion.

The importance of reference materials in doping-control analysis.

PubMed

Mackay, Lindsey G; Kazlauskas, Rymantas

2011-08-01

Currently a large range of pure substance reference materials are available for calibration of doping-control methods. These materials enable traceability to the International System of Units (SI) for the results generated by World Anti-Doping Agency (WADA)-accredited laboratories. Only a small number of prohibited substances have threshold limits for which quantification is highly important. For these analytes only the highest quality reference materials that are available should be used. Many prohibited substances have no threshold limits and reference materials provide essential identity confirmation. For these reference materials the correct identity is critical and the methods used to assess identity in these cases should be critically evaluated. There is still a lack of certified matrix reference materials to support many aspects of doping analysis. However, in key areas a range of urine matrix materials have been produced for substances with threshold limits, for example 19-norandrosterone and testosterone/epitestosterone (T/E) ratio. These matrix-certified reference materials (CRMs) are an excellent independent means of checking method recovery and bias and will typically be used in method validation and then regularly as quality-control checks. They can be particularly important in the analysis of samples close to threshold limits, in which measurement accuracy becomes critical. Some reference materials for isotope ratio mass spectrometry (IRMS) analysis are available and a matrix material certified for steroid delta values is currently under production. In other new areas, for example the Athlete Biological Passport, peptide hormone testing, designer steroids, and gene doping, reference material needs still need to be thoroughly assessed and prioritised.

New Fe-based superconductors: properties relevant for applications

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

Putti, M; Pallecchi, I; Bellingeri, E

2009-01-01

Less than two years after the discovery of high temperature superconductivity in oxypnictide LaFeAs(O, F) several families of superconductors based on Fe layers (1111, 122, 11, 111) are available. They share several characteristics with cuprate superconductors that compromise easy applications, such as the layered structure, the small coherence length and unconventional pairing. On the other hand, the Fe-based superconductors have metallic parent compounds and their electronic anisotropy is generally smaller and does not strongly depend on the level of doping, and the supposed order parameter symmetry is s-wave, thus in principle not so detrimental to current transmission across grain boundaries.more » From the application point of view, the main efforts are still devoted to investigate the superconducting properties, to distinguish intrinsic from extrinsic behaviors and to compare the different families in order to identify which one is the fittest for the quest for better and more practical superconductors. The 1111 family shows the highest T{sub c}, huge but also the most anisotropic upper critical field and in-field, fan-shaped resistive transitions reminiscent of those of cuprates. On the other hand, the 122 family is much less anisotropic with sharper resistive transitions as in low temperature superconductors, but with about half the T{sub c} of the 1111 compounds. An overview of the main superconducting properties relevant to applications will be presented. Upper critical field, electronic anisotropy parameter, and intragranular and intergranular critical current density will be discussed and compared, where possible, across the Fe-based superconductor families.« less

Large pinning forces and matching effects in YBa2Cu3O7-δ thin films with Ba2Y(Nb/Ta)O6 nano-precipitates

PubMed Central

Opherden, Lars; Sieger, Max; Pahlke, Patrick; Hühne, Ruben; Schultz, Ludwig; Meledin, Alexander; Van Tendeloo, Gustaaf; Nast, Rainer; Holzapfel, Bernhard; Bianchetti, Marco; MacManus-Driscoll, Judith L.; Hänisch, Jens

2016-01-01

The addition of mixed double perovskite Ba2Y(Nb/Ta)O6 (BYNTO) to YBa2Cu3O7−δ (YBCO) thin films leads to a large improvement of the in-field current carrying capability. For low deposition rates, BYNTO grows as well-oriented, densely distributed nanocolumns. We achieved a pinning force density of 25 GN/m3 at 77 K at a matching field of 2.3 T, which is among the highest values reported for YBCO. The anisotropy of the critical current density shows a complex behavior whereby additional maxima are developed at field dependent angles. This is caused by a matching effect of the magnetic fields c-axis component. The exponent N of the current-voltage characteristics (inversely proportional to the creep rate S) allows the depinning mechanism to be determined. It changes from a double-kink excitation below the matching field to pinning-potential-determined creep above it. PMID:26887291

Simulations of High Current NuMI Magnetic Horn Striplines at FNAL

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

Sipahi, Taylan; Biedron, Sandra; Hylen, James

2016-06-01

Both the NuMI (Neutrinos and the Main Injector) beam line, that has been providing intense neutrino beams for several Fermilab experiments (MINOS, MINERVA, NOVA), and the newly proposed LBNF (Long Baseline Neutrino Facility) beam line which plans to produce the highest power neutrino beam in the world for DUNE (the Deep Underground Neutrino Experiment) need pulsed magnetic horns to focus the mesons which decay to produce the neutrinos. The high-current horn and stripline design has been evolving as NuMI reconfigures for higher beam power and to meet the needs of the LBNF design. The CSU particle accelerator group has aidedmore » the neutrino physics experiments at Fermilab by producing EM simulations of magnetic horns and the required high-current striplines. In this paper, we present calculations, using the Poisson and ANSYS Maxwell 3D codes, of the EM interaction of the stripline plates of the NuMI horns at critical stress points. In addition, we give the electrical simulation results using the ANSYS Electric code. These results are being used to support the development of evolving horn stripline designs to handle increased electrical current and higher beam power for NuMI upgrades and for LBNF« less

The development of an internet-based knowledge exchange platform for pediatric critical care clinicians worldwide*.

PubMed

Wolbrink, Traci A; Kissoon, Niranjan; Burns, Jeffrey P

2014-03-01

Advances in Internet technology now enable unprecedented global collaboration and collective knowledge exchange. Up to this time, there have been limited efforts to use these technologies to actively promote knowledge exchange across the global pediatric critical care community. To develop an open-access, peer-reviewed, not-for-profit Internet-based learning application, OPENPediatrics, a collaborative effort with the World Federation of Pediatric Intensive and Critical Care Societies, was designed to promote postgraduate educational knowledge exchange for physicians, nurses, and others caring for critically ill children worldwide. Description of program development. International multicenter tertiary pediatric critical care units across six continents. Multidisciplinary pediatric critical care providers. A software application, providing information on demand, curricular pathways, and videoconferencing, downloaded to a local computer. In 2010, a survey assessing postgraduate educational needs was distributed through World Federation of Pediatric Intensive and Critical Care Societies to constituent societies. Four hundred and twenty-nine critical care providers from 49 countries responded to the single e-mail survey request. Respondents included 68% physicians and 28% nurses who care for critically ill children. Fifty-two percent of respondents reported accessing the Internet at least weekly to obtain professional educational information. The five highest requests were for educational content on respiratory care [mechanical ventilation] (48% [38%]), sepsis (28%), neurology (25%), cardiology (14%), extracorporeal membrane oxygenation (10%), and ethics (8%). Based on these findings, and in collaboration with researchers in adult learning and online courseware, an application was developed and is currently being used by 770 registered users in 60 countries. We describe here the development and implementation of an Internet-based application which is among the first efforts designed to promote global knowledge exchange for physicians and nurses caring for critically ill children. This application has the potential to evolve new methods in postgraduate education. Ongoing assessment of the efficacy of Internet-based learning platforms will be necessary.

Dispositional Differences in Critical Thinking Related to Gender and Academic Major.

ERIC Educational Resources Information Center

Walsh, Catherine M.; Hardy, Robert C.

1999-01-01

The California Critical Thinking Disposition Inventory was completed by 334 college students. Majors in English, psychology, and nursing scored highest. Nonpractice disciplines (English, history, psychology) generally scored higher than practice disciplines (nursing, education, business). Females scored higher on open-mindedness and maturity. (SK)

On the road to self-sputtering in high power impulse magnetron sputtering: particle balance and discharge characteristics

NASA Astrophysics Data System (ADS)

Huo, Chunqing; Lundin, Daniel; Raadu, Michael A.; Anders, André; Tomas Gudmundsson, Jon; Brenning, Nils

2014-04-01

The onset and development of self-sputtering (SS) in a high power impulse magnetron sputtering (HiPIMS) discharge have been studied using a plasma chemical model and a set of experimental data, taken with an aluminum target and argon gas. The model is tailored to duplicate the discharge in which the data are taken. The pulses are long enough to include both an initial transient and a following steady state. The model is used to unravel how the internal discharge physics evolves with pulse power and time, and how it is related to features in the discharge current-voltage-time characteristics such as current densities, maxima, kinks and slopes. The connection between the self-sputter process and the discharge characteristics is quantified and discussed in terms of three parameters: a critical target current density Jcrit based on the maximum refill rate of process (argon) gas above the target, an SS recycling factor ΠSS-recycle, and an approximation \\tilde{\\alpha} of the probabilities of ionization of species that come from the target (both sputtered metal and embedded argon atoms). For low power pulses, discharge voltages UD ⩽ 380 V with peak current densities below ≈ 0.2 A cm-2, the discharge is found to be dominated by process gas sputtering. In these pulses there is an initial current peak in time, associated with partial gas rarefaction, which is followed by a steady-state-like plateau in all parameters similar to direct current magnetron sputtering. In contrast, high power pulses, with UD ⩾ 500 V and peak current densities above JD ≈ 1.6 A cm-2, make a transition to a discharge mode where SS dominates. The transition is found not to be driven by process gas rarefaction which is only about 10% at this time. Maximum gas rarefaction is found later in time and always after the initial peak in the discharge current. With increasing voltage, and pulse power, the discharge can be described as following a route where the role of SS increases in four steps: process gas sputtering, gas-sustained SS, self-sustained SS and SS runaway. At the highest voltage, 1000 V, the discharge is very close to, but does not go into, the SS runaway mode. This absence of runaway is proposed to be connected to an unexpected finding: that twice ionized ions of the target species play almost no role in this discharge, not even at the highest powers. This reduces ionization by secondary-emitted energetic electrons almost to zero in the highest power range of the discharge.

14 CFR 27.1045 - Cooling test procedures.

Code of Federal Regulations, 2014 CFR

2014-01-01

... highest temperature recorded, as appropriate to the test condition; (2) That stage of flight is completed... configuration most critical for cooling; and (2) Under the conditions most critical for cooling. (b) Temperature stabilization. For the purpose of the cooling tests, a temperature is “stabilized” when its rate of change is...

14 CFR 27.1045 - Cooling test procedures.

Code of Federal Regulations, 2013 CFR

2013-01-01

... highest temperature recorded, as appropriate to the test condition; (2) That stage of flight is completed... configuration most critical for cooling; and (2) Under the conditions most critical for cooling. (b) Temperature stabilization. For the purpose of the cooling tests, a temperature is “stabilized” when its rate of change is...

14 CFR 27.1045 - Cooling test procedures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... highest temperature recorded, as appropriate to the test condition; (2) That stage of flight is completed... configuration most critical for cooling; and (2) Under the conditions most critical for cooling. (b) Temperature stabilization. For the purpose of the cooling tests, a temperature is “stabilized” when its rate of change is...

14 CFR 27.1045 - Cooling test procedures.

Code of Federal Regulations, 2012 CFR

2012-01-01

... highest temperature recorded, as appropriate to the test condition; (2) That stage of flight is completed... configuration most critical for cooling; and (2) Under the conditions most critical for cooling. (b) Temperature stabilization. For the purpose of the cooling tests, a temperature is “stabilized” when its rate of change is...

Sustained hole inversion layer in a wide-bandgap metal-oxide semiconductor with enhanced tunnel current

NASA Astrophysics Data System (ADS)

Shoute, Gem; Afshar, Amir; Muneshwar, Triratna; Cadien, Kenneth; Barlage, Douglas

2016-02-01

Wide-bandgap, metal-oxide thin-film transistors have been limited to low-power, n-type electronic applications because of the unipolar nature of these devices. Variations from the n-type field-effect transistor architecture have not been widely investigated as a result of the lack of available p-type wide-bandgap inorganic semiconductors. Here, we present a wide-bandgap metal-oxide n-type semiconductor that is able to sustain a strong p-type inversion layer using a high-dielectric-constant barrier dielectric when sourced with a heterogeneous p-type material. A demonstration of the utility of the inversion layer was also investigated and utilized as the controlling element in a unique tunnelling junction transistor. The resulting electrical performance of this prototype device exhibited among the highest reported current, power and transconductance densities. Further utilization of the p-type inversion layer is critical to unlocking the previously unexplored capability of metal-oxide thin-film transistors, such applications with next-generation display switches, sensors, radio frequency circuits and power converters.

Role of Combination Antimicrobial Therapy for Vancomycin-Resistant Enterococcus faecium Infections: Review of the Current Evidence.

PubMed

Yim, Juwon; Smith, Jordan R; Rybak, Michael J

2017-05-01

Enterococcus species are the second most common cause of nosocomial infections in the United States and are particularly concerning in critically ill patients with preexisting comorbid conditions. Rising resistance to antimicrobials that were historically used as front-line agents for treatment of enterococcal infections, such as ampicillin, vancomycin, and aminoglycosides, further complicates the treatment of these infections. Of particular concern are Enterococcus faecium strains that are associated with the highest rate of vancomycin resistance. The introduction of antimicrobial agents with specific activity against vancomycin-resistant Enterococcus (VRE) faecium including daptomycin, linezolid, quinupristin-dalfopristin, and tigecycline did not completely resolve this clinical dilemma. In this review, the mechanisms of action and resistance to currently available anti-VRE antimicrobial agents including newer agents such as oritavancin and dalbavancin will be presented. In addition, novel combination therapies including β-lactams and fosfomycin, and the promising results from in vitro, animal studies, and clinical experience in the treatment of VRE faecium will be discussed. © 2017 Pharmacotherapy Publications, Inc.

The relationship among critical thinking skill measured by science virtual test, gender, andmotivation in 9th grade students

NASA Astrophysics Data System (ADS)

Fernandi, R. A. U. I.; Firman, H.; Rusyati, L.

2018-05-01

The purpose of this study was to identify the relationship among critical thinking skill, gender and motivation in 9th grade students of Junior High School in Kuningan. This descriptive study used purposive sampling that comprised 110 ninth grade students taken from three junior high school that has good computer literacy and use 2013 curriculum. The data were obtained through Science Virtual Test on living things and environmental sustainability theme, respondent identity, and science motivation questionnaire (SMQ). Female students scored highest on generating purpose skill (M = 73.81), while male students performed better on generating implication and consequences skill (M = 78.01) where both groups differed significantly (p = 0.011). Students scored highest on generating purpose skill for high and moderate motivation group, while for the lowest score, moderate and low motivation group performed it on making assumption skill. Additionally, some critical thinking elements differed significantly by motivation to learn science. Despite, there was no correlation between students’ critical thinking and motivation (r = 0.155, p > 0.05). The finding indicated that students’ critical thinking is not differed by gender and not affected by motivation to learn science.

Adsorption characteristics of activated carbon fibers (ACFs) for toluene: application in respiratory protection.

PubMed

Balanay, Jo Anne G; Bartolucci, Alfred A; Lungu, Claudiu T

2014-01-01

Granular activated carbon (GAC) is currently the standard adsorbent in respirators against several gases and vapors because of its efficiency, low cost, and available technology. However, a drawback of GAC due to its granular form is its need for containment, adding weight and bulkiness to respirators. This makes respirators uncomfortable to wear, resulting in poor compliance in their use. Activated carbon fibers (ACF) are considered viable alternative adsorbent materials for developing thinner, light-weight, and efficient respirators because of their larger surface area, lighter weight, and fabric form. This study aims to determine the critical bed depth and adsorption capacity of different types of commercially available ACFs for toluene to understand how thin a respirator can be and the service life of the adsorbents, respectively. ACF in cloth (ACFC) and felt (ACFF) forms with three different surface areas per form were tested. Each ACF type was challenged with six concentrations of toluene (50, 100, 200, 300, 400, 500 ppm) at constant air temperature (23°C), relative humidity (50%), and airflow (16 LPM) at different adsorbent weights and bed depths. Breakthrough data were obtained for each adsorbent using gas chromatography with flame ionization detector. The ACFs' surface areas were measured by an automatic physisorption analyzer. The results showed that ACFC has a lower critical bed depth and higher adsorption capacity compared to ACFF with similar surface area for each toluene concentration. Among the ACF types, ACFC2000 (cloth with the highest measured surface area of 1614 ± 5 m(2)/g) has one of the lowest critical bed depths (ranging from 0.11-0.22 cm) and has the highest adsorption capacity (ranging from 595-878 mg/g). Based on these studied adsorption characteristics, it is concluded that ACF has great potential for application in respiratory protection against toluene, particularly the ACFC2000, which is the best candidate for developing thinner and efficient respirators.

Antimicrobial prescribing behaviour in dogs and cats by Belgian veterinarians.

PubMed

Van Cleven, Alexia; Sarrazin, Steven; de Rooster, Hilde; Paepe, Dominique; Van der Meeren, Sofie; Dewulf, Jeroen

2018-03-17

The objective of this study is to survey general prescribing behaviour by Belgian companion animal veterinarians and to assess agreement of these practices with current treatment guidelines. Therefore an online survey was administered with five realistic and frequently occurring first-line cases to primary-care veterinary practitioners. For each case a predefined pattern of questions were asked about whether or not they would prescribe antimicrobials, if they would prescribe a non-antimicrobial treatment and if they would perform additional diagnostic steps. The responses were compared with recommendations in national guidelines and recent literature. The overall most prescribed antimicrobials were potentiated amoxicillin (43.0 per cent), fluoroquinolones (14.7 per cent), third-generation and fourth-generation cephalosporins (10.9 per cent) and tetracyclines (10.9 per cent). Only 48.3 per cent of the veterinarians complied with the guidelines in nearly all of the clinical scenarios (ie, prescribing antimicrobials when indicated, not prescribing antimicrobials when it is not indicated). Moreover, when prescribing highest priority critically important antimicrobials, susceptibility testing on bacterial cultures was performed in only 12.4 per cent of the prescriptions. The results showed that the prescribing behaviour of antimicrobial compounds by primary-care veterinary practitioners in dogs and cats is often not in agreement with national guidelines. Focus in improvement of this prescribing behaviour should be on performing the appropriate diagnostic steps and decreasing the use of highest priority critically important antimicrobials. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Enhancement in transport critical current density of ex situ PIT Ag/(Ba, K)Fe2As2 tapes achieved by applying a combined process of flat rolling and uniaxial pressing

NASA Astrophysics Data System (ADS)

Togano, Kazumasa; Gao, Zhaoshun; Matsumoto, Akiyoshi; Kumakura, Hiroaki

2013-11-01

We report that the transport critical current density Jc of ex situ powder-in-tube (PIT) processed (Ba, K)Fe2As2 (Ba-122) tapes can be significantly enhanced by applying uniaxial cold pressing at the final stage of deformation. The tapes were prepared by packing high quality precursor powder into a Ag tube, cycles of rolling and intermediate annealing, and pressing followed by the final heat treatment for sintering. The Jc values in applied magnetic fields were increased by almost one order of magnitude compared to the tapes processed without pressing, exceeding 104 A cm-2 at 4.2 K. We achieved the highest Jc (at 4.2 K and 10 T) of 2.1×104 A cm-2 among PIT-processed Fe-based wires and tapes reported so far. The Jc-H curves measured at higher temperatures maintain small field dependence up to around 20 K, suggesting that these tapes are promising for applications at higher temperatures as well as at liquid helium temperature. The microstructure investigations reveal that there are two possible causes of the large Jc enhancement by pressing: one is densification and the other is the change of crack structure. Optimization of processing parameters such as the reduction ratio of rolling and pressing is expected to yield further Jc enhancement.

State of emergency medicine in Colombia.

PubMed

Arbelaez, Christian; Patiño, Andrés

2015-01-01

Colombia is an upper-middle-income country with a population of 45 million people and one of the best national healthcare and medical education systems in South America. However, its widely diverse and difficult terrains hinder healthcare delivery to rural areas, creating disparities in healthcare access and outcomes between the urban and rural settings. Currently, emergency medical care is overwhelmingly provided by general practitioners without residency training, who obtain specialty consultations based on the medical/surgical condition identified. A few emergency medicine (EM) residency programs have sprouted over the last two decades in renowned academic institutions in the largest cities, producing high-quality EM specialists. With the establishment of EM as a specialty in 2005 and increasing recognition of the specialty, there has been an increasing demand for EM specialists in cities, which is only slowly being met by the current residencies. The critical challenges for EM in Colombia are both, establishing itself as a well-recognized specialty - by increasing academic production and reaching a critical mass of and unity among EM specialists - and providing the highest quality and safest emergency care to the people of Colombia - by improving capacity both in emergency departments and in the regional and national emergency response systems. Historically, the establishment of EM as a strongly organized specialty in other countries has spanned decades (e.g., the United States), and Colombia has been making significant progress in a similar trajectory.

High quality uniform YBCO film growth by the metalorganic deposition using trifluoroacetates

NASA Astrophysics Data System (ADS)

Wang, S. S.; Zhang, Z. L.; Wang, L.; Gao, L. K.; Liu, J.

2017-03-01

A need exists for the large-area superconducting YBa2Cu3O7-x (YBCO) films with high critical current density for microwave communication and/or electric power applications. Trifluoroacetic metalorganic (TFA-MOD) method is a promising low cost technique for large-scale production of YBCO films, because it does not need high vacuum device and is easily applicable to substrates of various shape and size. In this paper, double-sided YBCO films with maximum 2 in diameter were prepared on LaAlO3 substrates by TFA-MOD method. Inductive critical current densitiy Jc, microwave surface resistance Rs, as well as the microstructure were characterized. A newly homemade furnace system was used to epitaxially grown YBCO films, which can improve the uniformity of YBCO film significantly by gas supply and temperature distribution proper design. Results showed that the large area YBCO films were very uniform in microstructure and thickness distribution, an average inductive Jc in excess of 6 MA/cm2 with uniform distribution, and low Rs (10 GHz) below 0.3 mΩ at 77 K were obtained. Andthe film filter may be prepared to work at temperatures lower than 74 K. These results are very close to the highest value of YBCO films made by conventional vacuum method, so we show a very promising route for large-scale production of high quality large-area YBCO superconducting films at a lower cost.

Analysis of current-driven oscillatory dynamics of single-layer homoepitaxial islands on crystalline conducting substrates

NASA Astrophysics Data System (ADS)

Dasgupta, Dwaipayan; Kumar, Ashish; Maroudas, Dimitrios

2018-03-01

We report results of a systematic study on the complex oscillatory current-driven dynamics of single-layer homoepitaxial islands on crystalline substrate surfaces and the dependence of this driven dynamical behavior on important physical parameters, including island size, substrate surface orientation, and direction of externally applied electric field. The analysis is based on a nonlinear model of driven island edge morphological evolution that accounts for curvature-driven edge diffusion, edge electromigration, and edge diffusional anisotropy. Using a linear theory of island edge morphological stability, we calculate a critical island size at which the island's equilibrium edge shape becomes unstable, which sets a lower bound for the onset of time-periodic oscillatory dynamical response. Using direct dynamical simulations, we study the edge morphological dynamics of current-driven single-layer islands at larger-than-critical size, and determine the actual island size at which the migrating islands undergo a transition from steady to time-periodic asymptotic states through a subcritical Hopf bifurcation. At the highest symmetry of diffusional anisotropy examined, on {111} surfaces of face-centered cubic crystalline substrates, we find that more complex stable oscillatory states can be reached through period-doubling bifurcation at island sizes larger than those at the Hopf points. We characterize in detail the island morphology and dynamical response at the stable time-periodic asymptotic states, determine the range of stability of these oscillatory states terminated by island breakup, and explain the morphological features of the stable oscillating islands on the basis of linear stability theory.

High transport current superconductivity in powder-in-tube Ba0.6K0.4Fe2As2 tapes at 27 T

NASA Astrophysics Data System (ADS)

Huang, He; Yao, Chao; Dong, Chiheng; Zhang, Xianping; Wang, Dongliang; Cheng, Zhe; Li, Jianqi; Awaji, Satoshi; Wen, Haihu; Ma, Yanwei

2018-01-01

The high upper critical field and low anisotropy of iron-based superconductors (IBS) make them particularly attractive for high-field applications, especially for the construction of next-generation nuclear magnetic resonance spectrometers, particle accelerators and high-field magnets. However, for practical use it is essential to make IBS materials into wire and tape conductors with sufficient current carrying capability, which is limited by misaligned grains inside the conductors. Here, based on a simple and low-cost powder-in-tube (PIT) method, we demonstrate a high transport critical current density (J c) reaching 1.5 × 105 A cm-2 (I c = 437 A) at 4.2 K and 10 T in Ba0.6K0.4Fe2As2 (Ba-122) tapes by texturing the grain orientation with optimized hot-press technique. The transport J c measured at 4.2 K under high magnetic fields of 27 T is still on the level of 5.5 × 104 A cm-2. Moreover, at 20 K and 5 T the transport J c is also as high as 5.4 × 104 A cm-2, showing a promising application potential in moderate temperature range which can be reached by liquid hydrogen or cryogenic cooling. All these J c values are the highest ever reported for IBS wires and tapes. The high-performance PIT Ba-122 tapes in this work suggest IBS to be a strong potential competitor of cuprate superconductors for the race of high-field applications in the future.

Tunneling Spectroscopy of Superconducting MoN and NbTiN Grown by Atomic Layer Deposition.

DOE PAGES

Groll, Nickolas; Klug, Jeffrey A.; Cao, Chaoyue; ...

2014-03-03

A tunneling spectroscopy study is presented of superconducting MoN and Nbo.8Tio.2N thin films grown by atomic layer deposition (ALD). The films exhibited a superconducting gap of 2meV and 2.4meV, respectively, with a corresponding critical temperature of 11.5K and 13.4 K, among the highest reported Tc values achieved by the ALD technique.Tunnel junctions were obtained using a mechanical contact method with a Au tip. While the native oxides of these films provided poor tunnel barriers, high quality tunnel junctions with low zero bias conductance (below rvl0%) were obtained using an artificial tunnel barrier of Ah03 on the film's surface grown exmore » situ by ALD. We find a large critical current density on the order of 4 x 106Ncm2 at T =0.8Tc for a 60 run MoN film and demonstrate conformal coating capabilities of ALD onto high aspect ratio geometries. These results suggest that the ALD technique offers significant promise for thin film superconducting device applications.« less

Tunneling spectroscopy of superconducting MoN and NbTiN grown by atomic layer deposition

NASA Astrophysics Data System (ADS)

Groll, Nickolas R.; Klug, Jeffrey A.; Cao, Chaoyue; Altin, Serdar; Claus, Helmut; Becker, Nicholas G.; Zasadzinski, John F.; Pellin, Michael J.; Proslier, Thomas

2014-03-01

A tunneling spectroscopy study is presented of superconducting MoN and Nb0.8Ti0.2N thin films grown by atomic layer deposition (ALD). The films exhibited a superconducting gap of 2 meV and 2.4 meV, respectively, with a corresponding critical temperature of 11.5 K and 13.4 K, among the highest reported Tc values achieved by the ALD technique. Tunnel junctions were obtained using a mechanical contact method with a Au tip. While the native oxides of these films provided poor tunnel barriers, high quality tunnel junctions with low zero bias conductance (below ˜10%) were obtained using an artificial tunnel barrier of Al2O3 on the film's surface grown ex situ by ALD. We find a large critical current density on the order of 4 × 106 A/cm2 at T = 0.8Tc for a 60 nm MoN film and demonstrate conformal coating capabilities of ALD onto high aspect ratio geometries. These results suggest that the ALD technique offers significant promise for thin film superconducting device applications.

Development of very high J c in Ba(Fe 1-xCo x) 2As 2 thin films grown on CaF 2

DOE PAGES

Tarantini, C.; Kametani, F.; Lee, S.; ...

2014-12-03

Ba(Fe 1-xCo x) 2As 2 is the most tunable of the Fe-based superconductors (FBS) in terms of acceptance of high densities of self-assembled and artificially introduced pinning centres which are effective in significantly increasing the critical current density, J c. Moreover, FBS are very sensitive to strain, which induces an important enhancement in critical temperature,T c, of the material. In this study we demonstrate that strain induced by the substrate can further improve J c of both single and multilayer films by more than that expected simply due to the increase in T c. The multilayer deposition of Ba(Fe 1-xComore » x) 2As 2 on CaF 2 increases the pinning force density (F p=J c x μ₀H) by more than 60% compared to a single layer film, reaching a maximum of 84 GN/m 3 at 22.5 T and 4.2 K, the highest value ever reported in any 122 phase.« less

Critical current and electric transport properties of superconducting epitaxial Nb(Ti)N submicron structures

NASA Astrophysics Data System (ADS)

Klimov, A.; Słysz, W.; Guziewicz, M.; Kolkovsky, V.; Wegrzecki, M.; Bar, J.; Marchewka, M.; Seredyński, B.

2016-12-01

Critical current and current-voltage characteristics of epitaxial Nb(Ti)N submicron ultrathin structures were measured as function of temperature. For 700-nm-wide bridge we found current-driven vortex de-pinning at low temperatures and thermally activated flux flow closer to the transition temperature, as the limiting factors for the critical current density. For 100-nm-wide meander we observed combination of phase-slip activation and vortex-anti-vortex pair (VAP) thermal excitation. Our Nb(Ti)N meander structure demonstrates high de-pairing critical current densities 107 A/cm2 at low temperatures, but the critical currents are much smaller due to presence of the local constrictions.

Scientific publications in critical care medicine journals from East Asia: A 10-year survey of the literature.

PubMed

Cao, Zhenyu; Ou, Chongyang; Teng, Hongfei; Liu, Xiguang; Tang, Hongxin

2016-01-01

The quantity and quality of publications in critical care medicine from East Asia haven't been reported. This study aimed to investigate the contribution of publications from East Asia. Articles from China, Japan and South Korea in 2005 to 2014 were retrieved from Web of Science and Pubmed. The number of publications, impact factor, citation, and article types were analyzed. There were 3076 publications from East Asia (1720 from China, 913 from Japan, and 443 from South Korea). There were a significant decrease in publications from Japan (p = 0.024) and significant increases from China (p = 0.000) and South Korea (p = 0.009). From 2006, the number of articles from China exceed Japan. China had the highest total impact factor (6618.48) and citation (18416), followed by Japan (4566.03; 15440) and South Korea (1998.19; 5599). Japan had the highest mean impact factor (5.00) and citations (16.91), followed by South Korea (4.51; 12.64) and China (3.85; 10.71). China and South Korea`s contributions to critical care medicine had significant increases during the past 10 years, while Japan had a significant decrease. China was the most productive region in East Asia since 2006. Japan had the highest quality research output.

Critical thinking competence and disposition of clinical nurses in a medical center.

PubMed

Feng, Rung-Chuang; Chen, Mei-Jung; Chen, Mei-Chuan; Pai, Yu-Chu

2010-06-01

Critical thinking is essential in nursing practice. Promoting critical thinking competence in clinical nurses is an important way to improve problem solving and decision-making competence to further improve the quality of patient care. However, using an adequate tool to test nurses' critical thinking competence and disposition may provide the reference criteria for clinical nurse characterization, training planning, and resource allocation for human resource management. The purpose of this study was to measure the critical thinking competence and critical thinking disposition of clinical nurses as well as to explore the related factors of critical thinking competence. Clinical nurses from four different clinical ladders selected from one medical center were stratified randomly. All qualified subjects who submitted valid questionnaires were included in the study. A Taiwan version of the modified Watson-Glaser Critical Thinking Appraisal and Critical Thinking Disposition Inventory was developed to measure the critical thinking competence and critical thinking disposition of clinical nurses. Validity was evaluated using the professional content test (content validity index = .93). Reliability was assessed with a Cronbach's alpha coefficient of .85. Data were analyzed using the SPSS for Windows (Version 12.0; SPSS Inc., Chicago, IL). Results showed that competence of interpretation was the highest critical thinking competence factor. Inference was the lowest, and reflective thinking as a critical thinking disposition was more positive. In addition, age, years of nursing experience, and experiences in other hospitals significantly influenced critical thinking competence (p < .05). Factors of age, years of experience, and nurses clinical ladder were shown to affect critical thinking disposition scores. Clinical ladder N4 nurses had the highest scores in both competence and disposition. A significant relationship was found between critical thinking competence and disposition scores, with 29.3% of the variance in critical thinking competence potentially explained by total years of nurse hospital experience. Clinical ladder and age were predictive factors for critical thinking disposition. Commonality was 27.9%. Nursing experience and clinical ladders positively affect critical thinking competence and disposition. Issues of critical thinking competence increasingly need to be measured. Therefore, appropriate tools for nursing professions should be further developed and explored for specific areas of practice.

Deleterious Effects From Occupational Exposure to Ethylene Thiourea in Pregnant Women.

PubMed

Mutic, Abby D; Baker, Brenda J; McCauley, Linda A

2017-12-01

Human exposure to endocrine disrupting chemicals (EDCs) has become common as a result of widespread application of these chemicals to the food supply, environmental contamination, and occupational exposures (Caserta et al., 2011). However, relatively little is known about the effects of EDCs such as ethylene thiourea (ETU) in developing fetuses and the lasting implications of this disruption on human development from birth through adulthood. Of highest concern are chronic, low-dose exposures among industrial and agricultural workers. Current knowledge regarding the significance of endocrine thyroid signaling on normal human development raises serious concerns about the possible deleterious effects of EDCs in the developing fetus, children, and mature adults. Occupational health nurses are critical in identifying women and families at increased risk of ETU exposure and mitigating early exposures in pregnancy.

[From cradle to grave? Expectations from atypical antipsychotics].

PubMed

Frecska, Ede

2005-03-01

Clinical expectations are high toward atypical, second generation antipsychotics (SGAs). Controlled clinical trials supporting the superiority of SGAs over traditional agents are scarce. Meta-analysis of existing data may come for the rescue but that kind of method has its limitations. One of the most meticulous approaches (Davis et al. 2003) reached the conclusion that some, but not all, SGAs are more efficacious than traditional ones. Within the group of distinguished drugs, clozapine and amisulpride have the highest efficacy. The present paper critically overviews the study of the Davis group. Based on in vivo D2 receptor binding data of the new SGAs and the usual post marketing changes of clinical dosing, it is expected that some of the currently and most recently marketed SGAs may show similar superiority.

Exercise Dose in Clinical Practice

PubMed Central

Wasfy, Meagan; Baggish, Aaron L.

2016-01-01

There is wide variability in the physical activity patterns of the patients in contemporary clinical cardiovascular practice. This review is designed to address the impact of exercise dose on key cardiovascular risk factors and on mortality. We begin by examining the body of literature that supports a dose-response relationship between exercise and cardiovascular disease risk factors including plasma lipids, hypertension, diabetes mellitus, and obesity. We next explore the relationship between exercise dose and mortality by reviewing the relevant epidemiological literature underlying current physical activity guideline recommendations. We then expand this discussion to critically examine recent data pertaining to the impact of exercise dose at the lowest and highest ends of the spectrum. Finally, we provide a framework for how the key concepts of exercise dose can be integrated into clinical practice. PMID:27267537

Exercise Dose in Clinical Practice.

PubMed

Wasfy, Meagan M; Baggish, Aaron L

2016-06-07

There is wide variability in the physical activity patterns of the patients in contemporary clinical cardiovascular practice. This review is designed to address the impact of exercise dose on key cardiovascular risk factors and on mortality. We begin by examining the body of literature that supports a dose-response relationship between exercise and cardiovascular disease risk factors, including plasma lipids, hypertension, diabetes mellitus, and obesity. We next explore the relationship between exercise dose and mortality by reviewing the relevant epidemiological literature underlying current physical activity guideline recommendations. We then expand this discussion to critically examine recent data pertaining to the impact of exercise dose at the lowest and highest ends of the spectrum. Finally, we provide a framework for how the key concepts of exercise dose can be integrated into clinical practice. © 2016 American Heart Association, Inc.

Are metal-organic frameworks able to provide a new generation of solid-phase microextraction coatings? - A review.

PubMed

Rocío-Bautista, Priscilla; Pacheco-Fernández, Idaira; Pasán, Jorge; Pino, Verónica

2016-10-05

Solid-phase microextraction (SPME) is a powerful technique commonly used in sample preparation for extraction/preconcentration of analytes from a wide variety of samples. Among the trends in improving SPME applications, current investigations are focused on the development of novel coatings able to improve the extraction efficiency, sensitivity, and thermal and mechanical stability, within other properties, of current commercial SPME fibers. Metal-organic frameworks (MOFs) merit to be highlighted as promising sorbent materials in SPME schemes. MOFs are porous hybrid materials composed by metal ions and organic linkers, presenting the highest surface areas known, with ease synthesis and high tuneability, together with adequate chemical and thermal stability. For MOF based-SPME fibers, it results important to pretreat adequately the SPME supports to ensure the correct formation of the MOF onto the fiber or the attachment MOF-support. This, in turn, will increase the final stability of the fiber while generating uniform coatings. This review provides a critical overview of the current state of the use of MOFs as SPME coatings, not only highlighting the advantages of these materials versus commercial SPME coatings in terms of stability, selectivity, and sensitivity; but also insightfully describing the current methods to obtain reproducible MOF-based SPME coatings. Copyright © 2016 Elsevier B.V. All rights reserved.

Experimental Analysis of Critical Current and Alternating Current Losses of High-Temperature Superconductor Tape with Resin and Gallium-Indium-Tin

PubMed Central

Sun, Yajie; Zhang, Huiming; Meng, Yuanzhu

2018-01-01

This paper experimentally analyzes the critical current degradation and AC (alternating current) losses of second-generation (2G) high-temperature superconductor (HTS) tape during the impregnation process. Two impregnation materials were utilized: Gallium-Indium-Tin (GaInSn), and an epoxy resin, Araldite. The critical current of the impregnation materials was measured after different thermal cycles and compared with the tape with no impregnation process. The experimental results show that the critical current of Yttrium Barium Copper Oxide (YBCO) short samples varies between differently impregnated materials. The resin, Araldite, degraded the critical current; however, the GaInSn showed no degradation. Two degradation patterns with Araldite were identified due to the impregnation process, and the corresponding causes were analyzed. We further measured the AC losses of tapes impregnated with liquid metal at different frequencies, up to 600 Hz. Based on the experimental results, GaInSn liquid metal should be the most suitable impregnation material in terms of critical current degradation. PMID:29642490

Experimental Analysis of Critical Current and Alternating Current Losses of High-Temperature Superconductor Tape with Resin and Gallium-Indium-Tin.

PubMed

Yu, Dongmin; Sun, Yajie; Zhang, Huiming; Meng, Yuanzhu; Liu, Huanan

2018-04-08

This paper experimentally analyzes the critical current degradation and AC (alternating current) losses of second-generation (2G) high-temperature superconductor (HTS) tape during the impregnation process. Two impregnation materials were utilized: Gallium-Indium-Tin (GaInSn), and an epoxy resin, Araldite. The critical current of the impregnation materials was measured after different thermal cycles and compared with the tape with no impregnation process. The experimental results show that the critical current of Yttrium Barium Copper Oxide (YBCO) short samples varies between differently impregnated materials. The resin, Araldite, degraded the critical current; however, the GaInSn showed no degradation. Two degradation patterns with Araldite were identified due to the impregnation process, and the corresponding causes were analyzed. We further measured the AC losses of tapes impregnated with liquid metal at different frequencies, up to 600 Hz. Based on the experimental results, GaInSn liquid metal should be the most suitable impregnation material in terms of critical current degradation.

Tourism and the conservation of critically endangered frogs.

PubMed

Morrison, Clare; Simpkins, Clay; Castley, J Guy; Buckley, Ralf C

2012-01-01

Protected areas are critical for the conservation of many threatened species. Despite this, many protected areas are acutely underfunded, which reduces their effectiveness significantly. Tourism is one mechanism to promote and fund conservation in protected areas, but there are few studies analyzing its tangible conservation outcomes for threatened species. This study uses the 415 IUCN critically endangered frog species to evaluate the contribution of protected area tourism revenue to conservation. Contributions were calculated for each species as the proportion of geographic range inside protected areas multiplied by the proportion of protected area revenues derived from tourism. Geographic ranges were determined from IUCN Extent of Occurrence maps. Almost 60% (239) of critically endangered frog species occur in protected areas. Higher proportions of total range are protected in Nearctic, Australasian and Afrotopical regions. Tourism contributions to protected area budgets ranged from 5-100%. These financial contributions are highest for developing countries in the Afrotropical, Indomalayan and Neotropical regions. Data for both geographic range and budget are available for 201 critically endangered frog species with proportional contributions from tourism to species protection ranging from 0.8-99%. Tourism's financial contributions to critically endangered frog species protection are highest in the Afrotropical region. This study uses a coarse measure but at the global scale it demonstrates that tourism has significant potential to contribute to global frog conservation efforts.

Tourism and the Conservation of Critically Endangered Frogs

PubMed Central

Morrison, Clare; Simpkins, Clay; Castley, J. Guy; Buckley, Ralf C.

2012-01-01

Protected areas are critical for the conservation of many threatened species. Despite this, many protected areas are acutely underfunded, which reduces their effectiveness significantly. Tourism is one mechanism to promote and fund conservation in protected areas, but there are few studies analyzing its tangible conservation outcomes for threatened species. This study uses the 415 IUCN critically endangered frog species to evaluate the contribution of protected area tourism revenue to conservation. Contributions were calculated for each species as the proportion of geographic range inside protected areas multiplied by the proportion of protected area revenues derived from tourism. Geographic ranges were determined from IUCN Extent of Occurrence maps. Almost 60% (239) of critically endangered frog species occur in protected areas. Higher proportions of total range are protected in Nearctic, Australasian and Afrotopical regions. Tourism contributions to protected area budgets ranged from 5–100%. These financial contributions are highest for developing countries in the Afrotropical, Indomalayan and Neotropical regions. Data for both geographic range and budget are available for 201 critically endangered frog species with proportional contributions from tourism to species protection ranging from 0.8–99%. Tourism's financial contributions to critically endangered frog species protection are highest in the Afrotropical region. This study uses a coarse measure but at the global scale it demonstrates that tourism has significant potential to contribute to global frog conservation efforts. PMID:22984440

Reframing convenience food.

PubMed

Jackson, Peter; Viehoff, Valerie

2016-03-01

This paper provides a critical review of recent research on the consumption of 'convenience' food, highlighting the contested nature of the term and exploring its implications for public health and environmental sustainability. It distinguishes between convenience food in general and particular types of convenience food, such as ready-meals, tracing the structure and growth of the market for such foods with a particular emphasis on the UK which currently has the highest rate of ready-meal consumption in Europe. Having established the definitional complexities of the term, the paper presents the evidence from a systematic review of the literature, highlighting the significance of convenience food in time-saving and time-shifting, the importance of recent changes in domestic labour and family life, and the way the consumption of convenience food is frequently moralized. The paper shows how current debates about convenience food are part of a longer discursive history about food, health and nutrition. It discusses current levels of public understanding about the links between convenience food, environmental sustainability and food waste. The paper concludes by making a case for understanding the consumption of convenience food in terms of everyday social practices, emphasising its habitual and routine character. Copyright © 2015 Elsevier Ltd. All rights reserved.

More Than One Million Children Served: Reading Recovery Results, 2000-2001.

ERIC Educational Resources Information Center

Reading Recovery Council of North America, Columbus, OH.

A key premise of Reading Recovery is that early intervention in first grade is critical in long-term literacy achievement because the gap between lowest- and highest-achieving children is narrow in lower grades but widens in later elementary school. Reading Recovery closes this gap at the critical time in children's literacy learning before the…

Effect of the composition on the superconducting properties of IBAD-MgO SmBCO coated conductors with superconducting film directly deposited on epi-MgO layer

NASA Astrophysics Data System (ADS)

Kim, H. S.; Oh, S. S.; Lee, N. J.; Jang, S. H.; Min, C. H.; Ha, H. S.; Chung, K. C.; Youm, D. J.; Moon, S. H.; Park, C.

2011-11-01

Sm1+xBa2-xCu3+yO7-δ (SmBCO) films were directly deposited on the epi-MgO/IBAD-MgO/Y2O3/Al2O3/Hastelloy template by co-evaporation using the evaporation using drum in dual chambers (EDDC) system without the buffer layer in order to investigate the effect of the composition ratios on superconducting property, microstructure and texture of SmBCO film. The films with gradient composition ratios of Sm:Ba:Cu were deposited using a shield with an opening which was placed between the substrate and the boats. The highest Ic of 52 A (corresponding to Jc = 1.6 MA/cm2 and a thickness of 800 nm) was observed at 77 K in self field at a composition x = 0.01-0.05 and y = -0.23 to -0.46. When the composition ratio is outside this range, the Ic value rapidly decreased. The superconducting critical current was highly dependent on the composition ratio. As the composition ratio is farther away from that of the highest Ic, the SmBCO (1 0 3) peak intensity increased and the amount of a-axis oriented parts increased. A dense microstructure with round-shape grains was observed in the region showing the highest Ic. The optimum composition ratio can be found by analyzing films deposited with variable deposition rates of each depositing element.

Criticality of iron and its principal alloying elements.

PubMed

Nuss, Philip; Harper, E M; Nassar, N T; Reck, Barbara K; Graedel, T E

2014-04-01

Because modern technology depends on reliable supplies of a wide variety of materials and because of increasing concern about those supplies, a comprehensive methodology was created to quantify the degree of criticality of the metals of the periodic table. In this paper, we apply this methodology to iron and several of its main alloying elements (i.e., vanadium, chromium, manganese, and niobium). These elements represent the basic metals of any industrial society and are vital for national security and economic well-being. Assessments relating to the dimensions of criticality - supply risk, vulnerability to supply restriction, and environmental implications - for 2008 are made on the global level and for the United States. Evaluations of each of the multiple indicators are presented, with aggregate results plotted in "criticality space", together with Monte Carlo simulation-derived "uncertainty cloud" estimates. Iron has the lowest supply risk, primarily because of its widespread geological occurrence. Vanadium displays the highest cradle-to-gate environmental implications, followed by niobium, chromium, manganese, and iron. Chromium and manganese, both essential in steel making, display the highest vulnerability to supply restriction, largely because substitution or substitution at equal performance is not possible for all end-uses. From a comprehensive perspective, we regard the overall criticality as low for iron and modest for the alloying elements we evaluated.

Critical currents of Nb sub 3 Sn wires for the US-DPC coil

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

Takayasu, M.; Gung, C.Y.; Steeves, M.M.

1991-03-01

This paper evaluates the critical current of titanium-alloyed internal-tin, jelly-roll Nb{sub 3}Sn wire for use in the US-DPC coil. It was confirmed from 14 randomly-selected samples that the critical-current values were uniform and consistent: the non-copper critical-current density was approximately 700 A/mm{sup 2} at 10 T and 4.2 K in agreement with expectations. A 27-strand cable-in-conduit conductor (CICC) using the low-thermal-coefficient-of-expansion superalloy Incoloy 905 yielded a critical current 5--7% below the average value of the single-strand data.

Development and validation of a risk model for identification of non-neutropenic, critically ill adult patients at high risk of invasive Candida infection: the Fungal Infection Risk Evaluation (FIRE) Study.

PubMed

Harrison, D; Muskett, H; Harvey, S; Grieve, R; Shahin, J; Patel, K; Sadique, Z; Allen, E; Dybowski, R; Jit, M; Edgeworth, J; Kibbler, C; Barnes, R; Soni, N; Rowan, K

2013-02-01

There is increasing evidence that invasive fungal disease (IFD) is more likely to occur in non-neutropenic patients in critical care units. A number of randomised controlled trials (RCTs) have evaluated antifungal prophylaxis in non-neutropenic, critically ill patients, demonstrating a reduction in the risk of proven IFD and suggesting a reduction in mortality. It is necessary to establish a method to identify and target antifungal prophylaxis at those patients at highest risk of IFD, who stand to benefit most from any antifungal prophylaxis strategy. To develop and validate risk models to identify non-neutropenic, critically ill adult patients at high risk of invasive Candida infection, who would benefit from antifungal prophylaxis, and to assess the cost-effectiveness of targeting antifungal prophylaxis to high-risk patients based on these models. Systematic review, prospective data collection, statistical modelling, economic decision modelling and value of information analysis. Ninety-six UK adult general critical care units. Consecutive admissions to participating critical care units. None. Invasive fungal disease, defined as a blood culture or sample from a normally sterile site showing yeast/mould cells in a microbiological or histopathological report. For statistical and economic modelling, the primary outcome was invasive Candida infection, defined as IFD-positive for Candida species. Systematic review: Thirteen articles exploring risk factors, risk models or clinical decision rules for IFD in critically ill adult patients were identified. Risk factors reported to be significantly associated with IFD were included in the final data set for the prospective data collection. Data were collected on 60,778 admissions between July 2009 and March 2011. Overall, 383 patients (0.6%) were admitted with or developed IFD. The majority of IFD patients (94%) were positive for Candida species. The most common site of infection was blood (55%). The incidence of IFD identified in unit was 4.7 cases per 1000 admissions, and for unit-acquired IFD was 3.2 cases per 1000 admissions. Statistical modelling: Risk models were developed at admission to the critical care unit, 24 hours and the end of calendar day 3. The risk model at admission had fair discrimination (c-index 0.705). Discrimination improved at 24 hours (c-index 0.823) and this was maintained at the end of calendar day 3 (c-index 0.835). There was a drop in model performance in the validation sample. Economic decision model: Irrespective of risk threshold, incremental quality-adjusted life-years of prophylaxis strategies compared with current practice were positive but small compared with the incremental costs. Incremental net benefits of each prophylaxis strategy compared with current practice were all negative. Cost-effectiveness acceptability curves showed that current practice was the strategy most likely to be cost-effective. Across all parameters in the decision model, results indicated that the value of further research for the whole population of interest might be high relative to the research costs. The results of the Fungal Infection Risk Evaluation (FIRE) Study, derived from a highly representative sample of adult general critical care units across the UK, indicated a low incidence of IFD among non-neutropenic, critically ill adult patients. IFD was associated with substantially higher mortality, more intensive organ support and longer length of stay. Risk modelling produced simple risk models that provided acceptable discrimination for identifying patients at 'high risk' of invasive Candida infection. Results of the economic model suggested that the current most cost-effective treatment strategy for prophylactic use of systemic antifungal agents among non-neutropenic, critically ill adult patients admitted to NHS adult general critical care units is a strategy of no risk assessment and no antifungal prophylaxis. Funding for this study was provided by the Health Technology Assessment programme of the National Institute for Health Research.

Relationships between critical thinking ability and nursing competence in clinical nurses.

PubMed

Chang, Mei Jen; Chang, Ying-Ju; Kuo, Shih-Hsien; Yang, Yi-Hsin; Chou, Fan-Hao

2011-11-01

To examine the relationships between critical thinking ability and nursing competence in clinical nurses. There are few evidance-based data related to the relationship between critical thinking ability and nursing competence of clinical nurses. A cross-sectional and correlation research design was used. A total of 570 clinical nurses at a medical centre in southern Taiwan were recruited into this study. Two self-report questionnaires, the Watson-Glaser Critical Thinking Appraisal (WGCTA) and the Nursing Competence Scale (NCS), were used to collect data. The critical thinking ability of clinical nurses was at the middle level. The highest score for the subscales of the WGCTA was 'interpretation ability' and the lowest was 'inference ability'. The nursing competence of clinical nurses was at the middle level and above. The highest score for the subscales was 'caring ability' and the lowest was 'research ability'. Critical thinking ability had a significantly positive correlation with nursing competence. Critical thinking, working years, educational levels and position/title were the significant predictors of nursing competence, accounting for 32·9% of the variance. Critical thinking ability had a significantly positive correlation with nursing competence. The critical thinking ability of clinical nurses with a master's degree was significantly better than those with a bachelor's degree or a diploma and nurses with over five working years was significantly better than those with under five years. The findings of this study can further serve as a reference for nursing education to improve nursing curricula and teaching strategies for nurse preparation. It could also be a guideline for nursing administration personnel in on-the-job training and orientation programs for nursing staff. © 2011 Blackwell Publishing Ltd.

The Speaker Gender Gap at Critical Care Conferences.

PubMed

Mehta, Sangeeta; Rose, Louise; Cook, Deborah; Herridge, Margaret; Owais, Sawayra; Metaxa, Victoria

2018-06-01

To review women's participation as faculty at five critical care conferences over 7 years. Retrospective analysis of five scientific programs to identify the proportion of females and each speaker's profession based on conference conveners, program documents, or internet research. Three international (European Society of Intensive Care Medicine, International Symposium on Intensive Care and Emergency Medicine, Society of Critical Care Medicine) and two national (Critical Care Canada Forum, U.K. Intensive Care Society State of the Art Meeting) annual critical care conferences held between 2010 and 2016. Female faculty speakers. None. Male speakers outnumbered female speakers at all five conferences, in all 7 years. Overall, women represented 5-31% of speakers, and female physicians represented 5-26% of speakers. Nursing and allied health professional faculty represented 0-25% of speakers; in general, more than 50% of allied health professionals were women. Over the 7 years, Society of Critical Care Medicine had the highest representation of female (27% overall) and nursing/allied health professional (16-25%) speakers; notably, male physicians substantially outnumbered female physicians in all years (62-70% vs 10-19%, respectively). Women's representation on conference program committees ranged from 0% to 40%, with Society of Critical Care Medicine having the highest representation of women (26-40%). The female proportions of speakers, physician speakers, and program committee members increased significantly over time at the Society of Critical Care Medicine and U.K. Intensive Care Society State of the Art Meeting conferences (p < 0.05), but there was no temporal change at the other three conferences. There is a speaker gender gap at critical care conferences, with male faculty outnumbering female faculty. This gap is more marked among physician speakers than those speakers representing nursing and allied health professionals. Several organizational strategies can address this gender gap.

The role of silver in the processing and properties of Bi-2212

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

Lang, T.; Heeb, B.; Buhl, D.

1994-12-31

The influence of the silver content and the oxygen partial pressure on the solidus temperature and the weight loss during melting of Bi{sub 2}Sr{sub 2}Ca{sub 1}Cu{sub 2}O{sub x} has been examined by means of DTA and TGA. By decreasing the oxygen partial pressure the solidus is lowered (e.g. {triangle}T=59{degrees}C by decreasing pO{sub 2} from 1 atm to 0.001 atm) and the weight loss is increased. The addition of silver causes two effects: (a) the solidus is further decreased (e.g. 2wt% Ag lower T{sub solidus} by up to 25{degrees}C, depending on the oxygen partial pressure), (b) the weight loss during meltingmore » is reduced. Thick films (10-20 {mu}m in thickness) with 0 and 5 wt% silver and bulk samples with 0 and 2.7 wt% silver were melt processed in flowing oxygen on a silver substrate in the DTA, allowing the observation of the melting process and a good temperature control. The critical current densities are vigorously dependent on the maximum processing temperature. The highest j{sub c} in thick films (8000 A/cm{sup 2} at 77 K, O T) was reached by melting 7{degrees}C above the solidus temperature. The silver addition shows no significant effect on the processing parameters or the superconducting properties. The highest j{sub c} for bulk samples (1 mm in thickness) was obtained by partial melting at 900{degrees}C or 880{degrees}C, depending on the silver content of the powder (0 or 2.7 wt%). The j{sub c} of the samples is slightly enhanced from 1800 A/cm{sup 2} (at 77 K, O T) to 2000 A/cm{sup 2} by the silver addition. To be able to reach at least 80% of the maximum critical current density, the temperature has to be controlled in a window of 5{degrees}C for thick films and 17{degrees}C for bulk samples.« less

Annotated checklist of fish cestodes from South America

PubMed Central

Alves, Philippe V.; de Chambrier, Alain; Scholz, Tomáš; Luque, José L.

2017-01-01

Abstract An exhaustive literature search supplemented by a critical examination of records made it possible to present an annotated checklist of tapeworms (Cestoda) that, as adults or larvae (metacestodes), parasitize freshwater, brackish water and marine fishes, i.e. cartilaginous and bony fishes, in South America. The current knowledge of their species diversity, host associations and geographical distribution is reviewed. Taxonomic problems are discussed based on a critical evaluation of the literature and information on DNA sequences of individual taxa is provided to facilitate future taxonomic and phylogenetic studies. As expected, the current knowledge is quite uneven regarding the number of taxa and host-associations reported from the principal river basins and marine ecoregions. These differences may not only reflect the actual cestode richness but may also be due to the research effort that has been devoted to unravelling the diversity of these endoparasitic helminths in individual countries. A total of 297 valid species, 61 taxa identified to the generic level, in addition to unidentified cestodes, were recorded from 401 species of fish hosts. Among the recognized cestode orders, 13 have been recorded in South America, with the Onchoproteocephalidea displaying the highest species richness, representing c. 50% of all species diversity. The majority of records include teleost fish hosts (79%) that harbour larval and adult stages of cestodes, whereas stingrays (Myliobatiformes) exhibit the highest proportion of records (39%) among the elasmobranch hosts. Fish cestodes are ubiquitous in South America, being mostly recorded from the Warm Temperate Southeastern Pacific (WTSP; 31%) for marine hosts and the Amazon River basin (45%) for freshwater ones. The following problems were detected during the compilation of literary data: (i) unreliability of many records; (ii) poor taxonomic resolution, i.e. identification made only to the genus or even family level; (iii) doubtful host identification; and (iv) the absence of voucher specimens that would enable us to verify identification. It is thus strongly recommended to always deposit representative specimens in any type of studies, including faunal surveys and ecological studies. An analysis of the proportion of three basic types of studies, i.e. surveys, taxonomic and ecological papers, has shown a considerable increase of ecological studies over the last decade. PMID:28331385

Annotated checklist of fish cestodes from South America.

PubMed

Alves, Philippe V; de Chambrier, Alain; Scholz, Tomáš; Luque, José L

2017-01-01

An exhaustive literature search supplemented by a critical examination of records made it possible to present an annotated checklist of tapeworms (Cestoda) that, as adults or larvae (metacestodes), parasitize freshwater, brackish water and marine fishes, i.e. cartilaginous and bony fishes, in South America. The current knowledge of their species diversity, host associations and geographical distribution is reviewed. Taxonomic problems are discussed based on a critical evaluation of the literature and information on DNA sequences of individual taxa is provided to facilitate future taxonomic and phylogenetic studies. As expected, the current knowledge is quite uneven regarding the number of taxa and host-associations reported from the principal river basins and marine ecoregions. These differences may not only reflect the actual cestode richness but may also be due to the research effort that has been devoted to unravelling the diversity of these endoparasitic helminths in individual countries. A total of 297 valid species, 61 taxa identified to the generic level, in addition to unidentified cestodes, were recorded from 401 species of fish hosts. Among the recognized cestode orders, 13 have been recorded in South America, with the Onchoproteocephalidea displaying the highest species richness, representing c. 50% of all species diversity. The majority of records include teleost fish hosts (79%) that harbour larval and adult stages of cestodes, whereas stingrays (Myliobatiformes) exhibit the highest proportion of records (39%) among the elasmobranch hosts. Fish cestodes are ubiquitous in South America, being mostly recorded from the Warm Temperate Southeastern Pacific (WTSP; 31%) for marine hosts and the Amazon River basin (45%) for freshwater ones. The following problems were detected during the compilation of literary data: (i) unreliability of many records; (ii) poor taxonomic resolution, i.e. identification made only to the genus or even family level; (iii) doubtful host identification; and (iv) the absence of voucher specimens that would enable us to verify identification. It is thus strongly recommended to always deposit representative specimens in any type of studies, including faunal surveys and ecological studies. An analysis of the proportion of three basic types of studies, i.e. surveys, taxonomic and ecological papers, has shown a considerable increase of ecological studies over the last decade.

Bias sputtered NbN and superconducting nanowire devices

NASA Astrophysics Data System (ADS)

Dane, Andrew E.; McCaughan, Adam N.; Zhu, Di; Zhao, Qingyuan; Kim, Chung-Soo; Calandri, Niccolo; Agarwal, Akshay; Bellei, Francesco; Berggren, Karl K.

2017-09-01

Superconducting nanowire single photon detectors (SNSPDs) promise to combine near-unity quantum efficiency with >100 megacounts per second rates, picosecond timing jitter, and sensitivity ranging from x-ray to mid-infrared wavelengths. However, this promise is not yet fulfilled, as superior performance in all metrics is yet to be combined into one device. The highest single-pixel detection efficiency and the widest bias windows for saturated quantum efficiency have been achieved in SNSPDs based on amorphous materials, while the lowest timing jitter and highest counting rates were demonstrated in devices made from polycrystalline materials. Broadly speaking, the amorphous superconductors that have been used to make SNSPDs have higher resistivities and lower critical temperature (Tc) values than typical polycrystalline materials. Here, we demonstrate a method of preparing niobium nitride (NbN) that has lower-than-typical superconducting transition temperature and higher-than-typical resistivity. As we will show, NbN deposited onto unheated SiO2 has a low Tc and high resistivity but is too rough for fabricating unconstricted nanowires, and Tc is too low to yield SNSPDs that can operate well at liquid helium temperatures. By adding a 50 W RF bias to the substrate holder during sputtering, the Tc of the unheated NbN films was increased by up to 73%, and the roughness was substantially reduced. After optimizing the deposition for nitrogen flow rates, we obtained 5 nm thick NbN films with a Tc of 7.8 K and a resistivity of 253 μΩ cm. We used this bias sputtered room temperature NbN to fabricate SNSPDs. Measurements were performed at 2.5 K using 1550 nm light. Photon count rates appeared to saturate at bias currents approaching the critical current, indicating that the device's quantum efficiency was approaching unity. We measured a single-ended timing jitter of 38 ps. The optical coupling to these devices was not optimized; however, integration with front-side optical structures to improve absorption should be straightforward. This material preparation was further used to fabricate nanocryotrons and a large-area imager device, reported elsewhere. The simplicity of the preparation and promising device performance should enable future high-performance devices.

Epitaxial YBa2Cu3O7-x nanocomposite films and coated conductors from BaMO3 (M = Zr, Hf) colloidal solutions

NASA Astrophysics Data System (ADS)

Obradors, X.; Puig, T.; Li, Z.; Pop, C.; Mundet, B.; Chamorro, N.; Vallés, F.; Coll, M.; Ricart, S.; Vallejo, B.; Pino, F.; Palau, A.; Gázquez, J.; Ros, J.; Usoskin, A.

2018-04-01

Superconducting nanocomposites are the best material choice to address the performance required in power applications and magnets working under high magnetic fields. However, it is still challenging to sort out how to achieve the highest superconducting performance using attractive and competitive manufacturing processes. Colloidal solutions have been recently developed as a novel and very promising low cost route to manufacture nanocomposite coated conductors. Well dispersed and stabilized preformance nanoparticle solutions are first prepared with high concentrations and then mixed with the YBa2Cu3O7 metalorganic precursor solutions to generate colloidal solutions to grow the nanocomposite films. Here we demonstrate, for the first time, that non-reactive BaZrO3 and BaHfO3 perovskite preformed nanoparticles are suitable for growing high quality thin and thick films, and coated conductors with a homogeneous distribution and controlled particle size using this fabrication method. Additionally, we extend the nanoparticle content of the nanocomposites up to 20%-25% mol without any degradation of the superconducting properties. Thick nanocomposite films, up to 0.8 μm, have been prepared with a single deposition of low-fluorine solutions using an ink jet printing dispenser and we demonstrate that the preformed nanoparticles display only a very limited coarsening during the growth process and so high critical current densities J c (B) under high magnetic fields. These films show the highest critical currents achieved so far based on the colloidal solution approach, I c = 220 A/cm-w at 77 K and self-field, and they still have a high potential for further increase in the film thickness. Finally, we also show that nanocomposite YBa2Cu3O7-BaZrO3 coated conductors based on an alternating beam assisted deposited YSZ buffer layer on stainless steel metallic substrates can be developed based on these novel colloidal solutions. Non-reactive preformed oxide perovskite nanoparticles are therefore very promising elements to further advance the colloidal solution approach in the implementation of low cost and high performance coated conductors for high magnetic field applications.

Ozone dose-response relationships for spring oilseed rape and broccoli

NASA Astrophysics Data System (ADS)

De Bock, Maarten; Op de Beeck, Maarten; De Temmerman, Ludwig; Guisez, Yves; Ceulemans, Reinhart; Vandermeiren, Karine

2011-03-01

Tropospheric ozone is an important air pollutant with known detrimental effects for several crops. Ozone effects on seed yield, oil percentage, oil yield and 1000 seed weight were examined for spring oilseed rape ( Brassica napus cv. Ability). For broccoli ( Brassica oleracea L. cv. Italica cv. Monaco) the effects on fresh marketable weight and total dry weight were studied. Current ozone levels were compared with an increase of 20 and 40 ppb during 8 h per day, over the entire growing season. Oilseed rape seed yield was negatively correlated with ozone dose indices calculated from emergence until harvest. This resulted in an R2 of 0.24 and 0.26 ( p < 0.001) for the accumulated hourly O 3 exposure over a threshold of 40 ppb (AOT40) and the phytotoxic ozone dose above a threshold of 6 nmol m -2 s -1 (POD 6) respectively. Estimated critical levels, above which 5% yield reduction is expected, were 3.7 ppm h and 4.4 mmol m -2 respectively. Our results also confirm that a threshold value of 6 nmol s -1 m -2 projected leaf area, as recommended for agricultural crops (UNECE, Mills, 2004), can indeed be applied for spring oilseed rape. The reduction of oilseed rape yield showed the highest correlation with the ozone uptake during the vegetative growth stage: when only the first 47 days after emergence were used to calculate POD 6, R2 values increased up to 0.476 or even 0.545 when the first 23 days were excluded. The highest ozone treatments, corresponding to the future ambient level by 2100 (IPCC, Meehl et al., 2007), led to a reduction of approximately 30% in oilseed rape seed yield in comparison to the current ozone concentrations. Oil percentage was also significantly reduced in response to ozone ( p < 0.001). As a consequence oil yield was even more severely affected by elevated ozone exposure compared to seed yield: critical levels for oil yield dropped to 3.2 ppm h and 3.9 mmol m -2. For broccoli the applied ozone doses had no effect on yield.

Dual burden of malnutrition in US Affiliated Pacific jurisdictions in the Children's Healthy Living Program.

PubMed

Novotny, Rachel; Li, Fenfang; Leon Guerrero, Rachael; Coleman, Patricia; Tufa, Aifili J; Bersamin, Andrea; Deenik, Jonathan; Wilkens, Lynne R

2017-05-22

Few data are available on dual burden of under and over nutrition of children in the Pacific region. The objective was to examine prevalence of stunting at birth and current stunting and their relationship to obesity in US Affiliated Pacific (USAP) jurisdictions. Cross sectional survey with cluster sampling by community. 5558, 2-8 years olds were measured in 51 communities in 11 USAP jurisdictions. The main outcome measures were stunting at birth, current stunting and obesity by body mass index. Prevalences of stunting at birth, current stunting and obesity were determined, adjusting for age distribution and community clustering. Differences by among age, sex, race and jurisdiction income levels were evaluated by chi-square analysis. Relationships of stunting at birth and current stunting with obesity were examined using a hierarchical model accounting for the study design. Prevalences were stunting at birth 6.8% (Standard Error, SE = 0.9%), current stunting 1.4% (SE = 0.2%) and obesity 14.03.8% (SE = 0.9%). Obesity was highest in upper middle income jurisdictions (UMIJ) at 17.5%. Stunting at birth differed by race (p = 0.0001) with highest prevalence among Native Hawaiian/Pacific Islanders (10.7%). Prevalence of stunting at birth was different by jurisdiction income level with 27.5% in lower middle income jurisdictions (LMIJ), and 22.2% in UMIJ, and 5.5% in higher than high income jurisdictions (HIJ) at 5.5% (p < 0.0001). Prevalence of current stunting was higher in LMIJ than HIJ (p = 0.001), although children with current stunting were less likely to have been stunted at birth. The association between stunting at birth and current stunting was negative (OR = 0.19, 95% CI: 0.05-0.69). Currently stunted children were marginally less likely to be obese than not stunted children in the USAP, where the prevalence of current stunting is low. Stunting (at birth and current) was highest in LMIJ, while UMIJ jurisdictions had the highest dual burden of malnutrition (that is the highest combination of both stunting at birth and obesity). National Institutes for Health clinical trial # NCT01881373 (clinicaltrials.gov).

Apparatus and method for measuring critical current properties of a coated conductor

DOEpatents

Mueller, Fred M [Los Alamos, NM; Haenisch, Jens [Dresden, DE

2012-07-24

The transverse critical-current uniformity in a superconducting tape was determined using a magnetic knife apparatus. A critical current I.sub.c distribution and transverse critical current density J.sub.c distribution in YBCO coated conductors was measured nondestructively with high resolution using a magnetic knife apparatus. The method utilizes the strong depression of J.sub.c in applied magnetic fields. A narrow region of low, including zero, magnetic field in a surrounding higher field is moved transversely across a sample of coated conductor. This reveals the critical current density distribution. A Fourier series inversion process was used to determine the transverse J.sub.c distribution in the sample.

Astrometric "Core-shifts" at the Highest Frequencies

NASA Technical Reports Server (NTRS)

Rioja, Maria; Dodson, Richard

2010-01-01

We discuss the application of a new VLBI astrometric method named "Source/Frequency Phase Referencing" to measurements of "core-shifts" in radio sources used for geodetic observations. We detail the reasons that astrometrical observations of 'core-shifts' have become critical in the era of VLBI2010. We detail how this new method allows the problem to be addressed at the highest frequencies and outline its superior compensation of tropospheric errors.

Efficient retention of mud drives land building on the Mississippi Delta plain

NASA Astrophysics Data System (ADS)

Esposito, Christopher R.; Shen, Zhixiong; Törnqvist, Torbjörn E.; Marshak, Jonathan; White, Christopher

2017-07-01

Many of the world's deltas - home to major population centers - are rapidly degrading due to reduced sediment supply, making these systems less resilient to increasing rates of relative sea-level rise. The Mississippi Delta faces some of the highest rates of wetland loss in the world. As a result, multibillion dollar plans for coastal restoration by means of river diversions are currently nearing implementation. River diversions aim to bring sediment back to the presently sediment-starved delta plain. Within this context, sediment retention efficiency (SRE) is a critical parameter because it dictates the effectiveness of river diversions. Several recent studies have focused on land building along the open coast, showing SREs ranging from 5 to 30 %. Here we measure the SRE of a large relict crevasse splay in an inland, vegetated setting that serves as an appropriate model for river diversions. By comparing the mass fraction of sand in the splay deposit to the estimated sand fraction that entered it during its life cycle, we find that this mud-dominated sediment body has an SRE of ≥ 75 %, i.e., dramatically higher than its counterparts on the open coast. Our results show that transport pathways for mud are critical for delta evolution and that SRE is highly variable across a delta. We conclude that sediment diversions located in settings that are currently still vegetated are likely to be the most effective in mitigating land loss and providing long-term sustainability.

Understanding the densification process of Bi2Sr2CaCu2Ox round wires with overpressure processing and its effect on critical current density

PubMed Central

Matras, M. R.; Jiang, J.; Larbalestier, D. C.; Hellstrom, E. E.

2016-01-01

Overpressure (OP) processing increases the critical current density (JC) of Bi2Sr2CaCu2Ox (2212) round wires by shrinking the surrounding Ag matrix around the 2212 filaments, driving them close to full density and greatly increasing the 2212 grain connectivity. Indeed densification is vital for attaining the highest JC. Here, we investigate the time and temperature dependence of the wire densification. We find that the wire diameter decreases by 3.8 ± 0.3 % after full heat treatment at 50 atm and 100 atm OP. At 50 atm OP pressure, the filaments start densifying above 700 °C and reach a 3.30 ± 0.07 % smaller diameter after 2 h at 820 °C, which is below the melting point of 2212 powder. The densification is homogeneous and does not change the filament shape before melting. The growth of non-superconducting phases is observed at 820 °C, suggesting that time should be minimized at high temperature prior to melting the 2212 powder. Study of an open-ended 2.2 m long wire sample shows that full densification and the high OP JC (JC varies by about 3.1 times over the 2.2 m long wire) is reached about 1 m from the open ends, thus showing that coil-length wires can be protected from leaky seals by adding at least 1 m of sacrificial wire at each end. PMID:28479675

Critical current scaling and the pivot-point in Nb3Sn strands

NASA Astrophysics Data System (ADS)

Tsui, Y.; Hampshire, D. P.

2012-05-01

Detailed measurements are provided of the engineering critical current density (Jc) and the index of transition (n-value) of two different types of advanced ITER Nb3Sn superconducting strand for fusion applications. The samples consist of one internal-tin strand (OST) and two bronze-route strands (BEAS I and BEAS II—reacted using different heat treatments). Tests on different sections of these wires show that prior to applying strain, Jc is homogeneous to better than 2% along the length of each strand. Jc data have been characterized as a function of magnetic field (B ≤ 14.5 T), temperature (4.2 K ≤ T ≤ 12 K) and applied axial strain ( - 1% ≤ ɛA ≤ 0.8%). Strain-cycling tests demonstrate that the variable strain Jc data are reversible to better than 2% when the applied axial strain is in the range of - 1% ≤ ɛA ≤ 0.5%. The wires are damaged when the intrinsic strain (ɛI) is ɛI ≥ 0.55% and ɛI ≥ 0.23% for the OST and BEAS strands, respectively. The strain dependences of the normalized Jc for each type of strand are similar to those of prototype strands of similar design measured in 2005 and 2008 to about 2% which makes them candidate strands for a round-robin interlaboratory comparison. The Jc data are described by Durham, ITER and Josephson-junction parameterizations to an accuracy of about 4%. For all of these scaling laws, the percentage difference between the data and the parameterization is larger when Jc is small, caused by high B, T or |ɛI|. The n-values can be described by a modified power law of the form n=1+r{I}_{{c}}^{s}, where r and s are approximately constant and Ic is the critical current. It has long been known that pivot-points (or cross-overs) in Jc occur at high magnetic field and temperature. Changing the magnetic field or temperature from one side of the pivot-point to the other changes the highest Jc sample to the lowest Jc sample and vice versa. The pivot-point follows the B-T phase boundary associated with the upper critical field and is usually attributed to the different tin content profiles and pinning properties of internal-tin and bronze-route strands. We report that the strain dependence of the pivot-point in these strands is quite different from that of the upper critical field and suggest that its origin in optimized high tin content strands is the proximity of the tetragonal Nb3Sn phase, which has low superconducting critical parameters.

Analysis of pesticides in surface water and sediment from Yolo Bypass, California, 2004-2005

USGS Publications Warehouse

Smalling, Kelly L.; Orlando, James L.; Kuivila, Kathryn

2005-01-01

Inputs to the Yolo Bypass are potential sources of pesticides that could impact critical life stages of native fish. To assess the direct inputs during inundation, pesticide concentrations were analyzed in water, in suspended and bed-sediment samples collected from six source watersheds to the Yolo Bypass, and from three sites within the Bypass in 2004 and 2005. Water samples were collected in February 2004 from the six input sites to the Bypass during the first flood event of the year representing pesticide inputs during high-flow events. Samples were also collected along a transect across the Bypass in early March 2004 and from three sites within the Bypass in the spring of 2004 under low-flow conditions. Low-flow data were used to understand potential pesticide contamination and its effects on native fish if water from these areas were used to flood the Bypass in dry years. To assess loads of pesticides to the Bypass associated with suspended sediments, large-volume water samples were collected during high flows in 2004 and 2005 from three sites, whereas bed sediments were collected from six sites in the fall of 2004 during the dry season. Thirteen current-use pesticides were detected in surface water samples collected during the study. The highest pesticide concentrations detected at the input sites to the Bypass corresponded to the first high-flow event of the year. The highest pesticide concentrations at the two sites sampled within the Bypass during the early spring were detected in mid-April following a major flood event as the water began to subside. The pesticides detected and their concentrations in the surface waters varied by site; however, hexazinone and simazine were detected at all sites and at some of the highest concentrations. Thirteen current-use pesticides and three organochlorine insecticides were detected in bed and suspended sediments collected in 2004 and 2005. The pesticides detected and their concentrations varied by site and sediment sample type. Trifluralin, p,p'-DDE, and p,p'-DDT were highest in the bed sediments, whereas oxyfluorfen and thiobencarb were highest in the suspended sediments. With the exception of the three organochlorine insecticides, suspended sediments had higher pesticide concentrations compared with bed sediments, indicating the potential for pesticide transport throughout the Bypass, especially during high-flow events. Understanding the distribution of pesticides between the water and sediment is needed to assess fate and transport within the Bypass and to evaluate the potential effects on native fish.

Study of the inhomogeneity of critical current under in-situ tensile stress for YBCO tape

NASA Astrophysics Data System (ADS)

Zhu, Y. P.; Chen, W.; Zhang, H. Y.; Liu, L. Y.; Pan, X. F.; Yang, X. S.; Zhao, Y.

2018-07-01

A Hall sensor system was used to measure the local critical current of YBCO tape with high spatial resolution under in-situ tensile stress. The hot spot generation and minimum quench energy of YBCO tape, which depended on the local critical current, was calculated through the thermoelectric coupling model. With the increase in tensile stress, the cracks which have different dimensions and critical current degradation arose more frequently and lowered the thermal stability of the YBCO tape.

Comparison of personal characteristics, tobacco use, and health states in Chaldean, Arab American, and non-Middle Eastern White adults.

PubMed

Jamil, H; Templin, T; Fakhouri, M; Rice, V H; Khouri, R; Fakhouri, H; Al-Omran, Hasan; Al-Fauori, Ibrahim; Baker, Omar

2009-08-01

This study compared and contrasted personal characteristics, tobacco use (cigarette and water pipe smoking), and health states in Chaldean, Arab American and non-Middle Eastern White adults attending an urban community service center. The average age was 39.4 (SD = 14.2). The three groups differed significantly (P < .006) on ethnicity, age, gender distribution, marital status, language spoken, education, employment, and annual income. Current cigarette smoking was highest for non-Middle Eastern White adults (35.4%) and current water pipe smoking was highest for Arab Americans (3.6%). Arab Americans were more likely to smoke both cigarettes and the narghile (4.3%). Health problems were highest among former smokers in all three ethnic groups. Being male, older, unmarried, and non-Middle Eastern White predicted current cigarette smoking; being Arab or Chaldean and having less formal education predicted current water pipe use.

PROCESS OF PHYSICAL DISABILITY AMONG OLDER ADULTS―CONTRIBUTION OF FRAILTY IN THE SUPER-AGED SOCIETY

PubMed Central

KUZUYA, MASAFUMI

2012-01-01

ABSTRACT One of the critical issues that Japan, well known for the world’s highest proportion of older adults, a super-aged society, is currently confronting is how to prevent physical disability in old age. This issue is particularly important not only from a medical perspective such as functional prognoses but also from a socio-economic angle in view of reducing the rapid rise in the cost of medical and long-term care insurance services. Functional decline in old age results not only from acute diseases but also from frailty. Such a common and important syndrome that is increasingly prevalent with advancing age can be the cause. The present article intends to review what is known about frailty, including its definition, epidemiology, and pathophysiology, and to examine potential areas of future research. PMID:22515109

Rapid determination of enantiomeric excess: a focus on optical approaches.

PubMed

Leung, Diana; Kang, Sung Ok; Anslyn, Eric V

2012-01-07

High-throughput screening (HTS) methods are becoming increasingly essential in discovering chiral catalysts or auxiliaries for asymmetric transformations due to the advent of parallel synthesis and combinatorial chemistry. Both parallel synthesis and combinatorial chemistry can lead to the exploration of a range of structural candidates and reaction conditions as a means to obtain the highest enantiomeric excess (ee) of a desired transformation. One current bottleneck in these approaches to asymmetric reactions is the determination of ee, which has led researchers to explore a wide range of HTS techniques. To be truly high-throughput, it has been proposed that a technique that can analyse a thousand or more samples per day is needed. Many of the current approaches to this goal are based on optical methods because they allow for a rapid determination of ee due to quick data collection and their parallel analysis capabilities. In this critical review these techniques are reviewed with a discussion of their respective advantages and drawbacks, and with a contrast to chromatographic methods (180 references). This journal is © The Royal Society of Chemistry 2012

Statistical algorithms improve accuracy of gene fusion detection

PubMed Central

Hsieh, Gillian; Bierman, Rob; Szabo, Linda; Lee, Alex Gia; Freeman, Donald E.; Watson, Nathaniel; Sweet-Cordero, E. Alejandro

2017-01-01

Abstract Gene fusions are known to play critical roles in tumor pathogenesis. Yet, sensitive and specific algorithms to detect gene fusions in cancer do not currently exist. In this paper, we present a new statistical algorithm, MACHETE (Mismatched Alignment CHimEra Tracking Engine), which achieves highly sensitive and specific detection of gene fusions from RNA-Seq data, including the highest Positive Predictive Value (PPV) compared to the current state-of-the-art, as assessed in simulated data. We show that the best performing published algorithms either find large numbers of fusions in negative control data or suffer from low sensitivity detecting known driving fusions in gold standard settings, such as EWSR1-FLI1. As proof of principle that MACHETE discovers novel gene fusions with high accuracy in vivo, we mined public data to discover and subsequently PCR validate novel gene fusions missed by other algorithms in the ovarian cancer cell line OVCAR3. These results highlight the gains in accuracy achieved by introducing statistical models into fusion detection, and pave the way for unbiased discovery of potentially driving and druggable gene fusions in primary tumors. PMID:28541529

Sustained hole inversion layer in a wide-bandgap metal-oxide semiconductor with enhanced tunnel current

PubMed Central

Shoute, Gem; Afshar, Amir; Muneshwar, Triratna; Cadien, Kenneth; Barlage, Douglas

2016-01-01

Wide-bandgap, metal-oxide thin-film transistors have been limited to low-power, n-type electronic applications because of the unipolar nature of these devices. Variations from the n-type field-effect transistor architecture have not been widely investigated as a result of the lack of available p-type wide-bandgap inorganic semiconductors. Here, we present a wide-bandgap metal-oxide n-type semiconductor that is able to sustain a strong p-type inversion layer using a high-dielectric-constant barrier dielectric when sourced with a heterogeneous p-type material. A demonstration of the utility of the inversion layer was also investigated and utilized as the controlling element in a unique tunnelling junction transistor. The resulting electrical performance of this prototype device exhibited among the highest reported current, power and transconductance densities. Further utilization of the p-type inversion layer is critical to unlocking the previously unexplored capability of metal-oxide thin-film transistors, such applications with next-generation display switches, sensors, radio frequency circuits and power converters. PMID:26842997

MgB2 wire diameter reduction by hot isostatic pressing—a route for enhanced critical current density

NASA Astrophysics Data System (ADS)

Morawski, A.; Cetner, T.; Gajda, D.; Zaleski, A. J.; Häßler, W.; Nenkov, K.; Rindfleisch, M. A.; Tomsic, M.; Przysłupski, P.

2018-07-01

The effect of wire diameter reduction on the critical current density of pristine MgB2 wire was studied. Wires were treated by a hot isostatic pressing method at 570 °C and at pressures of up to 1.1 GPa. It was found that the wire diameter reduction induces an increase of up to 70% in the mass density of the superconducting cores. This feature leads to increases in critical current, critical current density, and pinning force density. The magnitude and field dependence of the critical current density are related to both grain connectivity and structural defects, which act as effective pinning centers. High field transport properties were obtained without doping of the MgB2 phase. A critical current density jc of 3500 A mm‑2 was reached at 4 K, 6 T for the best sample, which was a five-fold increase compared to MgB2 samples synthesized at ambient pressure.

Law enforcement and the long gun: do we need a new face in the fight?

PubMed

Cannon, Mark

2013-11-01

The threat of rifles in the hands of criminals is now well recognized within law enforcement. Current emergency response systems are not equipped to operate in this combat-like environment. Growing statistics indicate that of the peace officers that were killed in the line of duty in the United States nearly half died by gunfire evidence. As Emergency Medical Services ("EMS") training and standards evolve, the lessons learned from the Tactical Combat Casualty Care doctrine should be incorporated to improve the safety and outcomes of injured law enforcement officers. Statistics show that deaths by gunfire have the highest average percentage of all officer deaths. Although new weapons, armor, and tactics are continually evolving to meet the challenge of officer safety, in the past decade, little has changed in how our EMS system responds to a critically wounded officer. Combat data from the US military leads us to believe that to save a wounded officer, emergency care must start immediately, regardless of the ongoing gun battle. It is time for the emergency medical system to evolve to meet the critical needs of today's law enforcement environment. Copyright © 2013 Elsevier Inc. All rights reserved.

The use of a modified pairwise comparison method in evaluating critical success factors for community-based rural homestay programmes

NASA Astrophysics Data System (ADS)

Daud, Shahidah Md; Ramli, Razamin; Kasim, Maznah Mat; Kayat, Kalsom; Razak, Rafidah Abd

2014-12-01

Tourism industry has become the highlighted sector which has amazingly increased the national income level. Despite the tourism industry being one of the highest income generating sectors, Homestay Programme as a Community-Based Tourism (CBT) product in Malaysia does not absorbed much of the incoming wealth. Homestay Programme refers to a programme in a community where a tourist stays together with a host family and experiences the everyday way of life of the family in both direct and indirect manner. There are over 100 Homestay Programme currently being registered with the Ministry of Culture and Tourism Malaysia which mostly are located in rural areas, but only a few excel and enjoying the fruit of the booming industry. Hence, this article seeks to identify the critical success factors for a Community-Based Rural Homestay Programme in Malaysia. A modified pairwise method is utilized to further evaluate the identified success factors in a more meaningful way. The findings will help Homestay Programme function as a community development tool that manages tourism resources. Thus, help the community in improving local economy and creating job opportunities.

Defining Advancement Career Paths and Succession Plans: Critical Human Capital Retention Strategies for High-Performing Advancement Divisions

ERIC Educational Resources Information Center

Croteau, Jon Derek; Wolk, Holly Gordon

2010-01-01

There are many factors that can influence whether a highly talented staff member will build a career within an institution or use it as a stepping stone. This article defines and explores the notions of developing career paths and succession planning and why they are critical human capital investment strategies in retaining the highest performers…

78 FR 4042 - Airworthiness Directives; The Boeing Company Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-18

... provides an option for a high frequency eddy current inspection for cracking of the critical fastener holes... for a high frequency eddy current inspection for cracking of the critical fastener holes, and repair..., August 9, 2007)), do a high frequency eddy current (HFEC) inspection for cracking of the four critical...

Advanced development of TFA-MOD coated conductors

NASA Astrophysics Data System (ADS)

Rupich, M. W.; Li, X.; Sathyamurthy, S.; Thieme, C.; Fleshler, S.

2011-11-01

American Superconductor is manufacturing 2G wire for initial commercial applications. The 2G wire properties satisfy the requirements for these initial projects; however, improvements in the critical current, field performance and cost are required to address the broad range of potential commercial and military applications. In order to meet the anticipated the performance and cost requirements, AMSC's R&D effort is focused on two major areas: (1) higher critical current and (2) enhanced flux pinning. AMSC's current 2G production wire, designed around a 0.8 μm thick YBCO layer deposited by a Metal Organic Deposition (MOD) process, carries a critical current in the range of 200-300 A/cm-w (77 K, sf). Achieving higher critical current requires increasing the thickness of the YBCO layer. This paper describes recent progress at AMSC on increasing the critical current of MOD-YBCO films using processes compatible with low-cost, high-rate manufacturing.

Identifying research priorities for effective retention strategies in clinical trials.

PubMed

Kearney, Anna; Daykin, Anne; Shaw, Alison R G; Lane, Athene J; Blazeby, Jane M; Clarke, Mike; Williamson, Paula; Gamble, Carrol

2017-08-31

The failure to retain patients or collect primary-outcome data is a common challenge for trials and reduces the statistical power and potentially introduces bias into the analysis. Identifying strategies to minimise missing data was the second highest methodological research priority in a Delphi survey of the Directors of UK Clinical Trial Units (CTUs) and is important to minimise waste in research. Our aim was to assess the current retention practices within the UK and priorities for future research to evaluate the effectiveness of strategies to reduce attrition. Seventy-five chief investigators of NIHR Health Technology Assessment (HTA)-funded trials starting between 2009 and 2012 were surveyed to elicit their awareness about causes of missing data within their trial and recommended practices for improving retention. Forty-seven CTUs registered within the UKCRC network were surveyed separately to identify approaches and strategies being used to mitigate missing data across trials. Responses from the current practice surveys were used to inform a subsequent two-round Delphi survey with registered CTUs. A consensus list of retention research strategies was produced and ranked by priority. Fifty out of seventy-five (67%) chief investigators and 33/47 (70%) registered CTUs completed the current practice surveys. Seventy-eight percent of trialists were aware of retention challenges and implemented strategies at trial design. Patient-initiated withdrawal was the most common cause of missing data. Registered CTUs routinely used newsletters, timeline of participant visits, and telephone reminders to mitigate missing data. Whilst 36 out of 59 strategies presented had been formally or informally evaluated, some frequently used strategies, such as site initiation training, have had no research to inform practice. Thirty-five registered CTUs (74%) participated in the Delphi survey. Research into the effectiveness of site initiation training, frequency of patient contact during a trial, the use of routinely collected data, the frequency and timing of reminders, triggered site training and the time needed to complete questionnaires was deemed critical. Research into the effectiveness of Christmas cards for site staff was not of critical importance. The surveys of current practices demonstrates that a variety of strategies are being used to mitigate missing data but with little evidence to support their use. Six retention strategies were deemed critically important within the Delphi survey and should be a primary focus of future retention research.

Flood-inundation maps for the Tippecanoe River at Winamac, Indiana

USGS Publications Warehouse

Menke, Chad D.; Bunch, Aubrey R.

2015-09-25

For this study, flood profiles were computed for the Tippecanoe River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at the Tippecanoe River streamgage, in combination with the current (2014) Federal Emergency Management Agency flood-insurance study for Pulaski County. The calibrated hydraulic model was then used to determine nine water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The 1-percent annual exceedance probability (AEP) flood stage (flood with recurrence intervals within 100 years) has not been determined yet for this streamgage location. The rating has not been developed for the 1-percent AEP because the streamgage dates to only 2001. The simulated water-surface profiles were then used with a geographic information system (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [lidar]) in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage 03331753, Tippecanoe River at Winamac, Ind., and forecast stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.

The relation of weight suppression and BMIz to bulimic symptoms in youth with bulimia nervosa.

PubMed

Accurso, Erin C; Lebow, Jocelyn; Murray, Stuart B; Kass, Andrea E; Le Grange, Daniel

2016-01-01

Weight suppression (WS), which is the difference between a patient's highest and current weight, has been associated with bulimic symptom severity in adults with bulimia nervosa (BN). However, the impact of WS on eating disorder psychopathology in youth with BN is unknown. Participants included 85 youth with DSM-5 BN who presented for outpatient treatment. Current WS was calculated as the difference between highest and current body mass index z-score (BMIz), while greatest WS was the difference between highest and lowest BMIz, both assessed at participants' current height. Separate multivariable linear regressions were conducted to determine if current or greatest WS was significantly associated with frequency of binge eating, compensatory behaviors, or dietary restraint. A secondary analysis was conducted on youth ages 16 and older, given the limitation of assessing WS at current height in younger participants with greater height instability. Youth with higher levels of greatest WS (but not current WS) were older, had a longer duration of illness, and reported greater weight and shape concern. When adjusting for BMIz, neither current nor greatest WS was significantly associated with bulimic behaviors or dietary restraint in the full sample. However, in the subset of youth ages 16 and older, current WS moderated the effect of BMIz on binge eating and compensatory behaviors. For youth with high WS, those with a high current BMIz engaged in more frequent binge eating than those with low current BMIz, and the negative impact of BMIz on compensatory behaviors became weaker. Our findings suggest that WS is clinically relevant in the presentation of youth with BN, and that it may need to be addressed as one important factor in BN psychopathology. Future studies using growth charts to determine historically highest and lowest BMIz may help to further elucidate the link (or lack thereof) between WS and BN psychopathology in youth.

NASA Astrophysics Data System (ADS)

Nishimura, A.; Takeuchi, T.; Nishijima, S.; Ochiai, K.; Nishijima, G.; Watanabe, K.; Shikama, T.

2010-04-01

To investigate the effect of neutron irradiation on superconducting properties, a collaboration network was established among superconducting material engineering and neutronics fields. Within the framework, irradiation test of Nb3Sn and Nb3Al wires by 14 MeV fusion neutron was planned and carried out at Fusion Neutronics Source in Japan Atomic Energy Agency. After the irradiation, critical current and critical magnetic field were measured with 28 T hybrid magnet at Institute for Metals Research in Tohoku University. The irradiation to 3.52×1020 n/m2 showed a slight increase of the critical current of the Nb3Sn wire, and the irradiation to 1.78×1021 n/m2 made the critical current appreciably larger. Regarding the critical magnetic field, no clear change was observed. In the case of Nb3Al wire, a sample irradiated to 1.78×1021 n/m2 showed no increase of the critical current below 200 A which was the limit of the power supply. As for the critical magnetic field, there was no clear improvement similar to the Nb3Sn wire. The increase of the critical current would be caused by knock-on effect of the fast neutron.

AC Loss Measurements on a 2G YBCO Coil

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

Rey, Christopher M; Duckworth, Robert C; Schwenterly, S W

2011-01-01

The Oak Ridge National Laboratory (ORNL) is collaborating with Waukesha Electric Systems (WES) to continue development of HTS power transformers. For compatibility with the existing power grid, a commercially viable HTS transformer will have to operate at high voltages in the range of 138 kV and above, and will have to withstand 550-kV impulse voltages as well. Second-generation (2G) YBCO coated conductors will be required for an economically-competitive design. In order to adequately size the refrigeration system for these transformers, the ac loss of these HTS coils must be characterized. Electrical AC loss measurements were conducted on a prototype highmore » voltage (HV) coil with co-wound stainless steel at 60 Hz in a liquid nitrogen bath using a lock-in amplifier technique. The prototype HV coil consisted of 26 continuous (without splice) single pancake coils concentrically centered on a stainless steel former. For ac loss measurement purposes, voltage tap pairs were soldered across each set of two single pancake coils so that a total of 13 separate voltage measurements could be made across the entire length of the coil. AC loss measurements were taken as a function of ac excitation current. Results show that the loss is primarily concentrated at the ends of the coil where the operating fraction of critical current is the highest and show a distinct difference in current scaling of the losses between low current and high current regimes.« less

Enhancing critical current density of cuprate superconductors

DOEpatents

Chaudhari, Praveen

2015-06-16

The present invention concerns the enhancement of critical current densities in cuprate superconductors. Such enhancement of critical current densities include using wave function symmetry and restricting movement of Abrikosov (A) vortices, Josephson (J) vortices, or Abrikosov-Josephson (A-J) vortices by using the half integer vortices associated with d-wave symmetry present in the grain boundary.

Enhancing superconducting critical current by randomness

NASA Astrophysics Data System (ADS)

Wang, Y. L.; Thoutam, L. R.; Xiao, Z. L.; Shen, B.; Pearson, J. E.; Divan, R.; Ocola, L. E.; Crabtree, G. W.; Kwok, W. K.

2016-01-01

The key ingredient of high critical currents in a type-II superconductor is defect sites that pin vortices. Contrary to earlier understanding on nanopatterned artificial pinning, here we show unequivocally the advantages of a random pinscape over an ordered array in a wide magnetic field range. We reveal that the better performance of a random pinscape is due to the variation of its local density of pinning sites (LDOPS), which mitigates the motion of vortices. This is confirmed by achieving even higher enhancement of the critical current through a conformally mapped random pinscape, where the distribution of the LDOPS is further enlarged. The demonstrated key role of LDOPS in enhancing superconducting critical currents gets at the heart of random versus commensurate pinning. Our findings highlight the importance of random pinscapes in enhancing the superconducting critical currents of applied superconductors.

Self-organized criticality in neural networks

NASA Astrophysics Data System (ADS)

Makarenkov, Vladimir I.; Kirillov, A. B.

1991-08-01

Possible mechanisms of creating different types of persistent states for informational processing are regarded. It is presented two origins of criticalities - self-organized and phase transition. A comparative analyses of their behavior is given. It is demonstrated that despite a likeness there are important differences. These differences can play a significant role to explain the physical issue of such highest functions of the brain as a short-term memory and attention. 1.

Magnetic Field Dependence of the Critical Current in S-N Bilayer Thin Films

NASA Technical Reports Server (NTRS)

Sadleir, John E.; Lee, Sang-Jun; Smith, Stephen James; Bandler, Simon; Chervenak, James; Kilbourne, Caroline A.; Finkbeiner, Fred M.; Porter, Frederick S.; Kelley, Richard L.; Adams, Joseph S.;

Foreign-born aged care workers in Australia: A growing trend.

PubMed

Negin, Joel; Coffman, Jenna; Connell, John; Short, Stephanie

2016-12-01

To address Australian aged care workforce challenges, a deeper understanding of the current care workforce is needed especially given estimated increases in demand. We provide a national picture of the aged care workforce in Australia focusing on country of birth. Data from the 2006 and 2011 Australian censuses. The majority of care workers are Australia-born followed by those born in the United Kingdom, South-East Asia and South Asia. While the number of carers from all regions has grown, the increase from 2006 to 2011 has been highest for carers from South Asia (333% increase) and sub-Saharan Africa (145%). The state with the largest decrease in the proportion of Australian-born care workers is Western Australia where Australian-born workers dropped from 62% in 2006 to 49% in 2011. Understanding the migration patterns of the aged care workforce in Australia is critical to health workforce planning given increasing demand. © 2016 AJA Inc.

Phenotypic heterogeneity of obesity-related brain vulnerability: one-size interventions will not fit all.

PubMed

Haley, Andreana P; Oleson, Stephanie; Pasha, Evan; Birdsill, Alex; Kaur, Sonya; Thompson, Janelle; Tanaka, Hirofumi

2018-05-09

Intact memory and problem solving are key to functional independence and quality of life in older age. Considering the unprecedented demographic shift toward a greater number of older adults than children in the United States in the next few decades, it is critically important for older adults to maintain work productivity and functional independence for as long as possible. Implementing early interventions focused on modifiable risk factors for cognitive decline at midlife is a strategy with the highest chance of success at present, bearing in mind the current lack of dementia cures. We present a selective, narrative review of evidence linking nutrition, body composition, vascular health, and brain function in midlife to highlight the phenotypic heterogeneity of obesity-related brain vulnerability and to endorse the development of individually tailored lifestyle modification plans for primary prevention of cognitive decline. © 2018 New York Academy of Sciences.

Single-vortex pinning and penetration depth in superconducting NdFeAsO 1-xF x

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

Zhang, Jessie T.; Kim, Jeehoon; Huefner, Magdalena

2015-10-12

We use a magnetic force microscope (MFM) to investigate single vortex pinning and penetration depth in NdFeAsO 1-xF x, one of the highest-T c iron-based superconductors. In fields up to 20 Gauss, we observe a disordered vortex arrangement, implying that the pinning forces are stronger than the vortex-vortex interactions. We measure the typical force to depin a single vortex, F depin ≃ 4.5 pN, corresponding to a critical current up to J c ≃ 7×10 5 A/cm 2. As a result, our MFM measurements allow the first local and absolute determination of the superconducting in-plane penetration depth in NdFeAsO 1-xFmore » x, λ ab = 320 ± 60 nm, which is larger than previous bulk measurements.« less

Competition versus regulation: constraining hospital discharge costs.

PubMed

Weil, T P

1996-01-01

A fundamental choice many states now face when implementing their cost containment efforts for the health field is to weigh the extent to which they should rely on either competitive or regulatory strategies. To study the efficacy of America's current market-driven approaches to constrain health expenditures, an analysis was undertaken of 1993 hospital discharge costs and related data of the 15 states in the United States with the highest percent of health maintenance organization (HMO) market penetration. The study's major finding was that a facility operating with a lesser number of paid hours was more critical in reducing average expense per discharge than whether the hospital was located in a "competitive" or a "regulated" state. What is proposed herein to enhance hospital cost containment efforts is for a state to almost simultaneously use both market-driven and regulatory strategies similar to what was implemented in California over the last three decades and in Germany for the last 100 years.

Difficulties in estimating the human burden of canine rabies.

PubMed

Taylor, Louise H; Hampson, Katie; Fahrion, Anna; Abela-Ridder, Bernadette; Nel, Louis H

2017-01-01

Current passive surveillance data for canine rabies, particularly for the regions where the burden is highest, are inadequate for appropriate decision making on control efforts. Poor enforcement of existing legislation and poor implementation of international guidance reduce the effectiveness of surveillance systems, but another set of problems relates to the fact that canine rabies is an untreatable condition which affects very poor sectors of society. This results in an unknown, but potentially large proportion of rabies victims dying outside the health system, deaths that are unlikely to be recorded by surveillance systems based on health center records. This article critically evaluates the potential sources of information on the number of human deaths attributable to canine rabies, and how we might improve the estimates required to move towards the goal of global canine rabies elimination. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Flux pinning in nanoparticle doped MgB 2/Cu tapes

NASA Astrophysics Data System (ADS)

Babić, E.; Kušević, I.; Husnjak, O.; Soltanian, S.; Wang, X. L.; Dou, S. X.

2007-09-01

The irreversibility fields Birr and critical current densities Jc of undoped and Si and SiC nanoparticle doped (5, 10 and 20 wt%) MgB2 tapes were measured in the temperature (T) range 2-38 K and in magnetic fields B ⩽ 16 T. Whereas Birr of undoped tapes varies smoothly with T, those of doped tapes show a change in slope around a crossover field Bcr which increases with nanoparticle content and also depends on their type. This indicates matching effect in vortex pinning, probably associated with Mg2Si nanoprecipitates formed during heat treatment. Indeed, Birr of doped tapes was enhanced in respect to that of undoped one with the highest enhancement for Birr ≈ Bcr, but the enhancement remained high ≈1.4 even for Birr ≫ Bcr (low temperatures). The variations of Jc and the pinning force density Fp = JcB with B and T support the above findings.

Critically appraised topic on adverse food reactions of companion animals (1): duration of elimination diets.

PubMed

Olivry, Thierry; Mueller, Ralf S; Prélaud, Pascal

2015-08-28

Restrictive (i.e. elimination)-provocation dietary trials remain the standard of care to diagnose cutaneous adverse food reactions (CAFRs) in dogs and cats. There is currently no consensus on the duration of elimination diet trials that would permit the highest sensitivity of diagnosis of CAFR in companion animals. The search for, and review and analysis of the best evidence available as of December 14, 2014 suggests that, by 5 weeks in dogs and 6 weeks in cats after starting an elimination diet, more than 80 % of patients had achieved a remission of clinical signs of CAFR. Increasing the diet trial duration to 8 weeks leads to a complete remission in more than 90 % of dogs and cats with CAFR. For diagnosing CAFRs in more than 90 % of dogs and cats, elimination diet trials should last at least 8 weeks.

Development of superconducting YBa2Cu3O(x) wires with low resistance electrical contacts

NASA Technical Reports Server (NTRS)

Buoncristiani, A. M.; Byvik, C. E.; Caton, R.; Selim, R.; Lee, B. I.; Modi, V.; Sherrill, M.; Leigh, H. D.; Fain, C. C.; Lewis, G.

1993-01-01

Materials exhibiting superconductivity above liquid nitrogen temperatures (77 K) will enable new applications of this phenomena. One of the first commercial applications of this technology will be superconducting magnets for medical imaging. However, a large number of aerospace applications of the high temperature superconducting materials have also been identified. These include magnetic suspension and balance of models in wind tunnels and resistanceless leads to anemometers. The development of superconducting wires fabricated from the ceramic materials is critical for these applications. The progress in application of a patented fiber process developed by Clemson University for the fabrication of superconducting wires is reviewed. The effect of particle size and heat treatment on the quality of materials is discussed. Recent advances made at Christopher Newport College in the development of micro-ohm resistance electrical contacts which are capable of carrying the highest reported direct current to this material is presented.

A Review of the Bayesian Occupancy Filter

PubMed Central

Saval-Calvo, Marcelo; Medina-Valdés, Luis; Castillo-Secilla, José María; Cuenca-Asensi, Sergio; Martínez-Álvarez, Antonio; Villagrá, Jorge

2017-01-01

Autonomous vehicle systems are currently the object of intense research within scientific and industrial communities; however, many problems remain to be solved. One of the most critical aspects addressed in both autonomous driving and robotics is environment perception, since it consists of the ability to understand the surroundings of the vehicle to estimate risks and make decisions on future movements. In recent years, the Bayesian Occupancy Filter (BOF) method has been developed to evaluate occupancy by tessellation of the environment. A review of the BOF and its variants is presented in this paper. Moreover, we propose a detailed taxonomy where the BOF is decomposed into five progressive layers, from the level closest to the sensor to the highest abstract level of risk assessment. In addition, we present a study of implemented use cases to provide a practical understanding on the main uses of the BOF and its taxonomy. PMID:28208638

Development of superconducting YBa2Cu3O(x) wires with low resistance electrical contacts

NASA Astrophysics Data System (ADS)

Buoncristiani, A. M.; Byvik, C. E.; Caton, R.; Selim, R.; Lee, B. I.; Modi, V.; Sherrill, M.; Leigh, H. D.; Fain, C. C.; Lewis, G.

Materials exhibiting superconductivity above liquid nitrogen temperatures (77 K) will enable new applications of this phenomena. One of the first commercial applications of this technology will be superconducting magnets for medical imaging. However, a large number of aerospace applications of the high temperature superconducting materials have also been identified. These include magnetic suspension and balance of models in wind tunnels and resistanceless leads to anemometers. The development of superconducting wires fabricated from the ceramic materials is critical for these applications. The progress in application of a patented fiber process developed by Clemson University for the fabrication of superconducting wires is reviewed. The effect of particle size and heat treatment on the quality of materials is discussed. Recent advances made at Christopher Newport College in the development of micro-ohm resistance electrical contacts which are capable of carrying the highest reported direct current to this material is presented.

Municipal solid waste management in Malaysia: practices and challenges.

PubMed

Manaf, Latifah Abd; Samah, Mohd Armi Abu; Zukki, Nur Ilyana Mohd

2009-11-01

Rapid economic development and population growth, inadequate infrastructure and expertise, and land scarcity make the management of municipal solid waste become one of Malaysia's most critical environmental issues. The study is aimed at evaluating the generation, characteristics, and management of solid waste in Malaysia based on published information. In general, the per capita generation rate is about 0.5-0.8 kg/person/day in which domestic waste is the primary source. Currently, solid waste is managed by the Ministry of Housing and Local Government, with the participation of the private sector. A new institutional and legislation framework has been structured with the objectives to establish a holistic, integrated, and cost-effective solid waste management system, with an emphasis on environmental protection and public health. Therefore, the hierarchy of solid waste management has given the highest priority to source reduction through 3R, intermediate treatment and final disposal.

Effect of hexagonal patterned arrays and defect geometry on the critical current of superconducting films

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

Sadovskyy, I. A.; Wang, Y. L.; Xiao, Z. -L.

Understanding the effect of pinning on the vortex dynamics in superconductors is a key factor towards controlling critical current values. Large-scale simulations of vortex dynamics can provide a rational approach to achieve this goal. Here, we use the time-dependent Ginzburg-Landau equations to study thin superconducting films with artificially created pinning centers arranged periodically in hexagonal lattices. We calculate the critical current density for various geometries of the pinning centers—varying their size, strength, and density. Furthermore, we shed light upon the influence of pattern distortion on the magnetic-field-dependent critical current. We compare our result directly with available experimental measurements on patternedmore » molybdenum-germanium films, obtaining good agreement. In conclusion, our results give important systematic insights into the mechanisms of pinning in these artificial pinning landscapes and open a path for tailoring superconducting films with desired critical current behavior.« less

Effect of hexagonal patterned arrays and defect geometry on the critical current of superconducting films

NASA Astrophysics Data System (ADS)

Sadovskyy, I. A.; Wang, Y. L.; Xiao, Z.-L.; Kwok, W.-K.; Glatz, A.

2017-02-01

Understanding the effect of pinning on the vortex dynamics in superconductors is a key factor towards controlling critical current values. Large-scale simulations of vortex dynamics can provide a rational approach to achieve this goal. Here, we use the time-dependent Ginzburg-Landau equations to study thin superconducting films with artificially created pinning centers arranged periodically in hexagonal lattices. We calculate the critical current density for various geometries of the pinning centers—varying their size, strength, and density. Furthermore, we shed light upon the influence of pattern distortion on the magnetic-field-dependent critical current. We compare our result directly with available experimental measurements on patterned molybdenum-germanium films, obtaining good agreement. Our results give important systematic insights into the mechanisms of pinning in these artificial pinning landscapes and open a path for tailoring superconducting films with desired critical current behavior.

Effect of hexagonal patterned arrays and defect geometry on the critical current of superconducting films

NASA Astrophysics Data System (ADS)

Sadovskyy, Ivan; Wang, Yonglei; Xiao, Zhili; Kwok, Wai-Kwong; Glatz, Andreas

Understanding the effect of pinning on the vortex dynamics in superconductors is a key factor towards controlling critical current values. Large-scale simulations of vortex dynamics can provide a rational approach to achieve this goal. Here, we use the time-dependent Ginzburg-Landau equations to study thin superconducting films with artificially created pinning centers arranged periodically in hexagonal lattices. We calculate the critical current density for various geometries of the pinning centers - varying their size, strength, and density. Furthermore, we shed light upon the influence of pattern distortion on the magnetic field dependent critical current. We compare our result directly with available experimental measurements on patterned molybdenum-germanium films, obtaining good agreement. Our results give important systematic insights into the mechanisms of pinning in these artificial pinning landscapes and open a path for tailoring superconducting films with desired critical current behavior.

Effect of hexagonal patterned arrays and defect geometry on the critical current of superconducting films

DOE PAGES

Sadovskyy, I. A.; Wang, Y. L.; Xiao, Z. -L.; ...

2017-02-07

Understanding the effect of pinning on the vortex dynamics in superconductors is a key factor towards controlling critical current values. Large-scale simulations of vortex dynamics can provide a rational approach to achieve this goal. Here, we use the time-dependent Ginzburg-Landau equations to study thin superconducting films with artificially created pinning centers arranged periodically in hexagonal lattices. We calculate the critical current density for various geometries of the pinning centers—varying their size, strength, and density. Furthermore, we shed light upon the influence of pattern distortion on the magnetic-field-dependent critical current. We compare our result directly with available experimental measurements on patternedmore » molybdenum-germanium films, obtaining good agreement. In conclusion, our results give important systematic insights into the mechanisms of pinning in these artificial pinning landscapes and open a path for tailoring superconducting films with desired critical current behavior.« less

17 CFR 404.2 - Records to be made and kept current by registered government securities brokers and dealers...

Code of Federal Regulations, 2010 CFR

2010-04-01

... on a consolidated basis, by the highest level holding company that is a Material Associated Person..., as of quarter-end for the registered government securities broker or dealer and its highest level... registered government securities broker or dealer and its highest level holding company that is a Material...

Upper critical field of high temperature Y(1.2)Ba(0.8)CuO(4-delta) superconductor

NASA Technical Reports Server (NTRS)

Hor, P. H.; Meng, R. L.; Huang, J. Z.; Chu, C. W.; Huang, C. Y.

1987-01-01

A 20-T high-field magnet is used to measure electrical resistance as a function of temperature in the Y(1.2)Ba(0.8)CuO(4-delta) superconductor. The temperature dependence of the critical field, Hc2(T), is obtained from the superconduction transition. A Hc2(O) value of 166T is determined which is the highest critical field yet reported. Results show Y(1.2)Ba(0.8)CuO(4-delta) to be a 90K Type-II superconductor, with a lower critical field Hc1(O) of about 0.2T and a penetration depth of about 290 A.

Evidence for criticality in financial data

NASA Astrophysics Data System (ADS)

Ruiz, G.; de Marcos, A. F.

2018-01-01

We provide evidence that cumulative distributions of absolute normalized returns for the 100 American companies with the highest market capitalization, uncover a critical behavior for different time scales Δt. Such cumulative distributions, in accordance with a variety of complex - and financial - systems, can be modeled by the cumulative distribution functions of q-Gaussians, the distribution function that, in the context of nonextensive statistical mechanics, maximizes a non-Boltzmannian entropy. These q-Gaussians are characterized by two parameters, namely ( q, β), that are uniquely defined by Δt. From these dependencies, we find a monotonic relationship between q and β, which can be seen as evidence of criticality. We numerically determine the various exponents which characterize this criticality.

Effect of magnetic field on the flux pinning mechanisms in Al and SiC co-doped MgB2 superconductor

NASA Astrophysics Data System (ADS)

Kia, N. S.; Ghorbani, S. R.; Arabi, H.; Hossain, M. S. A.

2018-07-01

MgB2 superconductor samples co-doped with 0.02 wt. Al2O3 and 0-0.05 wt. SiC were studied by magnetization - magnetic field (M-H) loop measurements at different temperatures. The critical current density has been calculated by the Bean model, and the irreversibility field, Hirr, has been obtained by the Kramer method. The pinning mechanism of the co-doped sample with 2% Al and 5% SiC was investigated in particular due to its having the highest Hirr. The normalized volume pinning force f = F/Fmax as a function of reduced magnetic field h = H/Hirr has been obtained, and the pinning mechanism was studied by the Dew-Houghes model. It was found that the normal point pinning (NPP), the normal surface pinning (NSP), and the normal volume pinning (NVP) mechanisms play the main roles. The magnetic field and temperature dependence of contributions of the NPP, NSP, and NVP pinning mechanisms were obtained. The results show that the contributions of the pinning mechanisms depend on the temperature and magnetic field. From the temperature dependence of the critical current density within the collective pinning theory, it was found that both the δl pinning due to spatial fluctuations of the charge-carrier mean free path and the δTc pinning due to randomly distributed spatial variations in the transition temperature coexist at zero magnetic field in co-doped samples. Yet, the charge-carrier mean-free-path fluctuation pinning (δl) is the only important pinning mechanism at non-zero magnetic fields.

The effect of fast neutron irradiation on the superconducting properties of REBCO coated conductors with and without artificial pinning centers

NASA Astrophysics Data System (ADS)

Fischer, D. X.; Prokopec, R.; Emhofer, J.; Eisterer, M.

2018-04-01

Superconductors are essential components of future fusion power plants. The magnet coils responsible for producing the field required for confining the fusion plasma are exposed to considerable neutron radiation. This makes irradiation studies necessary for understanding the radiation response of the superconductor. High temperature superconductors are promising candidates as magnet coil materials. YBCO and GdBCO tapes of several manufacturers were irradiated to fast neutron fluences of up to 3.9 × 1022 m-2 in the research reactor at the Atominstitut. Low energy neutrons contribute to the fission reactor spectrum but not to the expected spectrum at the fusion magnets. Low energy neutrons have to be shielded in irradiation experiments to avoid their substantial effect on the superconducting properties of tapes containing gadolinium. The critical current (I c) of the tapes in this study was examined at fields of up to 15 T and down to a temperature of 30 K. I c first increases upon irradiation and reaches a maximum at a certain fluence, which depends highly on temperature, being highest at low temperature. I c declines at high fluences and eventually degrades with respect to its initial value. Tapes with artificial pinning centers (APCs) degrade at lower fluences than tapes without them. The n-values decrease in all types of tapes after irradiation even when the critical currents are increased. The field dependence of the volume pinning force differs in pristine tapes with and without APCs but shows the same behavior after irradiation.

Understanding the densification process of Bi2Sr2CaCu2O x round wires with overpressure processing and its effect on critical current density

NASA Astrophysics Data System (ADS)

Matras, M. R.; Jiang, J.; Larbalestier, D. C.; Hellstrom, E. E.

2016-10-01

Overpressure (OP) processing increases the critical current density ({{\\boldsymbol{J}}}{{C}}) of Bi2Sr2CaCu2O x (2212) round wires by shrinking the surrounding Ag matrix around the 2212 filaments, driving them close to full density and greatly increasing the 2212 grain connectivity. Indeed densification is vital for attaining the highest {{\\boldsymbol{J}}}{{C}}. Here, we investigate the time and temperature dependence of the wire densification. We find that the wire diameter decreases by 3.8 ± 0.3% after full heat treatment at 50 atm and 100 atm OP. At 50 atm OP pressure, the filaments start densifying above 700 °C and reach a 3.30 ± 0.07% smaller diameter after 2 h at 820 °C, which is below the melting point of 2212 powder. The densification is homogeneous and does not change the filament shape before melting. The growth of non-superconducting phases is observed at 820 °C, suggesting that time should be minimized at high temperature prior to melting the 2212 powder. Study of an open-ended 2.2 m long wire sample shows that full densification and the high OP {{\\boldsymbol{J}}}{{C}} ({{\\boldsymbol{J}}}{{C}} varies by about 3.1 times over the 2.2 m long wire) is reached about 1 m from the open ends, thus showing that coil-length wires can be protected from leaky seals by adding at least 1 m of sacrificial wire at each end.

Memory characteristics of ring-shaped ceramic superconductors

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

Takeoka, A.; Hasunuma, M.; Sakaiya, S.

1989-03-01

For the practical application of ceramic superconductors, the authors investigated the residual magnetic field characteristics of ring-shaped ceramic superconductors in a Y-Ba-Cu-O system with high Tc. The residual magnetic field of a ring with asymmetric current paths, supplied by external currents, appeared when one of the branch currents was above the critical current. The residual magnetic field saturated when both brach currents exceeded the critical current of the ring and showed hysteresis-like characteristics. The saturated magnetic field is subject to the critical current of the ring. A superconducting ring with asymmetric current paths suggests a simple and quite new persistent-currentmore » type memory device.« less

Urinary Biomarkers for Phthalates Associated with Asthma in Norwegian Children

PubMed Central

Carlsen, Karin C. Lødrup; Calafat, Antonia M.; Hoppin, Jane A.; Håland, Geir; Mowinckel, Petter; Carlsen, Kai-Håkon; Løvik, Martinus

2012-01-01

Background: High-molecular-weight phthalates in indoor dust have been associated with asthma in children, but few studies have evaluated phthalate biomarkers in association with respiratory outcomes. Objectives: We explored the association between urinary concentrations of phthalate metabolites and current asthma. Methods: In a cross-sectional analysis, 11 metabolites of 8 phthalates [including four metabolites of di(2-ethylhexyl) phthalate] were measured in one first morning void collected from 2001 through 2004 from 623 10-year-old Norwegian children. Logistic regression models controlling for urine specific gravity, sex, parental asthma, and income were used to estimate associations between current asthma and phthalate metabolite concentrations by quartiles or as log10-transformed variables. Results: Current asthma was associated with both mono(carboxyoctyl) phthalate (MCOP) and mono(carboxynonyl) phthalate (MCNP), although the association was limited to those in the highest quartile of these chemicals. The adjusted odds ratio (aOR) for current asthma was 1.9 (95% CI: 1.0, 3.3) for the highest MCOP quartile compared with the lowest quartile, and 1.3 (95% CI: 0.98, 1.7) for an interquartile-range increase. The aOR for current asthma was 2.2 (95% CI: 1.2, 4.0) for the highest MCNP quartile and 1.3 (95% CI: 1.0, 1.7) for an interquartile-range increase. The other phthalate metabolites were not associated with current asthma. Conclusions: Current asthma was associated with the highest quartiles of MCOP and MCNP, metabolites of two high molecular weight phthalates, diisononyl phthalate and diisodecyl phthalate, respectively. Given the short biological half-life of the phthalates and the cross-sectional design, our findings should be interpreted cautiously. PMID:23164678

Larval assemblages of large and medium-sized pelagic species in the Straits of Florida

NASA Astrophysics Data System (ADS)

Richardson, David E.; Llopiz, Joel K.; Guigand, Cedric M.; Cowen, Robert K.

2010-07-01

Critical gaps in our understanding of the distributions, interactions, life histories and preferred habitats of large and medium-size pelagic fishes severely constrain the implementation of ecosystem-based, spatially structured fisheries management approaches. In particular, spawning distributions and the environmental characteristics associated with the early life stages are poorly documented. In this study, we consider the diversity, assemblages, and associated habitat of the larvae of large and medium-sized pelagic species collected during 2 years of monthly surveys across the Straits of Florida. In total, 36 taxa and 14,295 individuals were collected, with the highest diversity occurring during the summer and in the western, frontal region of the Florida Current. Only a few species (e.g. Thunnus obesus, T. alalunga, Tetrapturus pfluegeri) considered for this study were absent. Small scombrids (e.g. T. atlanticus, Katsuwonus pelamis, Auxis spp.) and gempylids dominated the catch and were orders of magnitude more abundant than many of the rare species (e.g. Thunnus thynnus,Kajikia albida). Both constrained (CCA) and unconstrained (NMDS) multivariate analyses revealed a number of species groupings including: (1) a summer Florida edge assemblage (e.g. Auxis spp., Euthynnus alleterattus, Istiophorus platypterus); (2) a summer offshore assemblage (e.g. Makaira nigricans, T. atlanticus, Ruvettus pretiosus, Lampris guttatus); (3) an ubiquitous assemblage (e.g. K. pelamis, Coryphaena hippurus, Xiphias gladius); and (4) a spring/winter assemblage that was widely dispersed in space (e.g. trachipterids). The primary environmental factors associated with these assemblages were sea-surface temperature (highest in summer-early fall), day length (highest in early summer), thermocline depth (shallowest on the Florida side) and fluorescence (highest on the Florida side). Overall, the results of this study provide insights into how a remarkable diversity of pelagic species spatially and temporally partition spawning within a region that is characterized by dynamic oceanography and strong habitat gradients.

Management and modeling approaches for controlling raccoon rabies: The road to elimination

PubMed Central

Chipman, Richard B.; Slate, Dennis; Huyvaert, Kathryn P.; VerCauteren, Kurt C.; Gilbert, Amy T.

2017-01-01

Rabies is an ancient viral disease that significantly impacts human and animal health throughout the world. In the developing parts of the world, dog bites represent the highest risk of rabies infection to people, livestock, and other animals. However, in North America, where several rabies virus variants currently circulate in wildlife, human contact with the raccoon rabies variant leads to the highest per capita population administration of post-exposure prophylaxis (PEP) annually. Previous rabies variant elimination in raccoons (Canada), foxes (Europe), and dogs and coyotes (United States) demonstrates that elimination of the raccoon variant from the eastern US is feasible, given an understanding of rabies control costs and benefits and the availability of proper tools. Also critical is a cooperatively produced strategic plan that emphasizes collaborative rabies management among agencies and organizations at the landscape scale. Common management strategies, alone or as part of an integrated approach, include the following: oral rabies vaccination (ORV), trap-vaccinate-release (TVR), and local population reduction. As a complement, mathematical and statistical modeling approaches can guide intervention planning, such as through contact networks, circuit theory, individual-based modeling, and others, which can be used to better understand and predict rabies dynamics through simulated interactions among the host, virus, environment, and control strategy. Strategies derived from this ecological lens can then be optimized to produce a management plan that balances the ecological needs and program financial resources. This paper discusses the management and modeling strategies that are currently used, or have been used in the past, and provides a platform of options for consideration while developing raccoon rabies virus elimination strategies in the US. PMID:28301480

Management and modeling approaches for controlling raccoon rabies: The road to elimination.

PubMed

Elmore, Stacey A; Chipman, Richard B; Slate, Dennis; Huyvaert, Kathryn P; VerCauteren, Kurt C; Gilbert, Amy T

2017-03-01

Rabies is an ancient viral disease that significantly impacts human and animal health throughout the world. In the developing parts of the world, dog bites represent the highest risk of rabies infection to people, livestock, and other animals. However, in North America, where several rabies virus variants currently circulate in wildlife, human contact with the raccoon rabies variant leads to the highest per capita population administration of post-exposure prophylaxis (PEP) annually. Previous rabies variant elimination in raccoons (Canada), foxes (Europe), and dogs and coyotes (United States) demonstrates that elimination of the raccoon variant from the eastern US is feasible, given an understanding of rabies control costs and benefits and the availability of proper tools. Also critical is a cooperatively produced strategic plan that emphasizes collaborative rabies management among agencies and organizations at the landscape scale. Common management strategies, alone or as part of an integrated approach, include the following: oral rabies vaccination (ORV), trap-vaccinate-release (TVR), and local population reduction. As a complement, mathematical and statistical modeling approaches can guide intervention planning, such as through contact networks, circuit theory, individual-based modeling, and others, which can be used to better understand and predict rabies dynamics through simulated interactions among the host, virus, environment, and control strategy. Strategies derived from this ecological lens can then be optimized to produce a management plan that balances the ecological needs and program financial resources. This paper discusses the management and modeling strategies that are currently used, or have been used in the past, and provides a platform of options for consideration while developing raccoon rabies virus elimination strategies in the US.

Submerged oceanic shoals of north Western Australia are a major reservoir of marine biodiversity

NASA Astrophysics Data System (ADS)

Moore, Cordelia; Cappo, Mike; Radford, Ben; Heyward, Andrew

2017-09-01

This paper provides a first assessment of fish communities associated with the submerged oceanic banks and shoals in north-west Australia. Until recently, little was known about these deeper and more inaccessible reefs. The mesophotic coral-reef habitats (20-80 m) were a major reservoir of marine biodiversity, with unique and exceptionally high fish diversity and abundance. Species richness in the study region was 1.4 times, and abundance almost twice, that recorded for similar mesophotic habitats on the Great Barrier Reef in north-east Australia. A review of the published literature revealed that Australia's NW oceanic shoals support the highest fish species richness reported for mesophotic reefs to date. We made regional comparisons of fish community structure (species composition, richness and abundance) and assessed the influence of depth, substrate and location. The presence of consolidated calcareous reef, depth and aspect (a surrogate for exposure) had the greatest influence on species richness. In contrast, aspect and the presence of benthic biota had the greatest influence on fish abundance. Sites most exposed to the prevailing currents (facing north-east) had lowest fish abundance, while highest abundances were recorded on moderately exposed sites (along the north-west and south-east edges). The most abundant species were small ( Pomacentrus coelestis) and large ( Naso hexacanthus) planktivorous fish. Currently, 29.3% of NE Australia mesophotic reefs are within no-take management zones of the Great Barrier Reef. In contrast, just 1.3% of the NW oceanic shoals are designated as no-take areas. The location and extent of mesophotic reefs remain poorly quantified globally. Because these habitats support significant biodiversity and have the potential to act as important refugia, understanding their extent is critical to maintaining coral-reef biodiversity and resilience and supporting sustainable management.

Theory of flux cutting and flux transport at the critical current of a type-II superconducting cylindrical wire

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

Clem, John R

2011-02-17

I introduce a critical-state theory incorporating both flux cutting and flux transport to calculate the magnetic-field and current-density distributions inside a type-II superconducting cylinder at its critical current in a longitudinal applied magnetic field. The theory is an extension of the elliptic critical-state model introduced by Romero-Salazar and Pérez-Rodríguez. The vortex dynamics depend in detail on two nonlinear effective resistivities for flux cutting (ρ{sub ∥}) and flux flow (ρ{sub ⊥}), and their ratio r=ρ{sub ∥}/ρ{sub ⊥}. When r<1, the low relative efficiency of flux cutting in reducing the magnitude of the internal magnetic-flux density leads to a paramagnetic longitudinal magneticmore » moment. As a model for understanding the experimentally observed interrelationship between the critical currents for flux cutting and depinning, I calculate the forces on a helical vortex arc stretched between two pinning centers when the vortex is subjected to a current density of arbitrary angle Φ. Simultaneous initiation of flux cutting and flux transport occurs at the critical current density J{sub c}(Φ) that makes the vortex arc unstable.« less

Theory of flux cutting and flux transport at the critical current of a type-II superconducting cylindrical wire

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

Clem, John R.

2011-02-17

I introduce a critical-state theory incorporating both flux cutting and flux transport to calculate the magnetic-field and current-density distributions inside a type-II superconducting cylinder at its critical current in a longitudinal applied magnetic field. The theory is an extension of the elliptic critical-state model introduced by Romero-Salazar and Perez-Rodriguez. The vortex dynamics depend in detail on two nonlinear effective resistivities for flux cutting ({rho}{parallel}) and flux flow ({rho}{perpendicular}), and their ratio r = {rho}{parallel}/{rho}{perpendicular}. When r < 1, the low relative efficiency of flux cutting in reducing the magnitude of the internal magnetic-flux density leads to a paramagnetic longitudinal magneticmore » moment. As a model for understanding the experimentally observed interrelationship between the critical currents for flux cutting and depinning, I calculate the forces on a helical vortex arc stretched between two pinning centers when the vortex is subjected to a current density of arbitrary angle {phi}. Simultaneous initiation of flux cutting and flux transport occurs at the critical current density J{sub c}({phi}) that makes the vortex arc unstable.« less

Theory of flux cutting and flux transport at the critical current of a type-II superconducting cylindrical wire

NASA Astrophysics Data System (ADS)

Clem, John R.

2011-06-01

I introduce a critical-state theory incorporating both flux cutting and flux transport to calculate the magnetic-field and current-density distributions inside a type-II superconducting cylinder at its critical current in a longitudinal applied magnetic field. The theory is an extension of the elliptic critical-state model introduced by Romero-Salazar and Pérez-Rodríguez. The vortex dynamics depend in detail on two nonlinear effective resistivities for flux cutting (ρ∥) and flux flow (ρ⊥), and their ratio r=ρ∥/ρ⊥. When r<1, the low relative efficiency of flux cutting in reducing the magnitude of the internal magnetic-flux density leads to a paramagnetic longitudinal magnetic moment. As a model for understanding the experimentally observed interrelationship between the critical currents for flux cutting and depinning, I calculate the forces on a helical vortex arc stretched between two pinning centers when the vortex is subjected to a current density of arbitrary angle ϕ. Simultaneous initiation of flux cutting and flux transport occurs at the critical current density Jc(ϕ) that makes the vortex arc unstable.

Respiratory therapists and critical-thinking behaviors: a self-assessment.

PubMed

Goodfellow, L T

2001-01-01

The purpose of this study was to assess critical-thinking behaviors of respiratory therapists through self-report. Using a quantitative survey research method, respiratory therapists rated themselves on seven critical thinking skills. The effects of personal variables on the self-assessments were also investigated. The respiratory therapists self-assessed their critical-thinking behaviors highest in the categories of prioritizing, troubleshooting, and communicating. Anticipating was self-assessed as the lowest-ranked critical-thinking behavior. Age and educational level were found to have no effect on the self-assessed behaviors, while years of experience in respiratory care and gender were found to affect self-assessed troubleshooting, decision making, and anticipating. The results of this study suggest that educators and clinicians should consider learning strategies that incorporate the use of experience when targeting novice practitioners.

Post-Discharge Bleeding after Percutaneous Coronary Intervention and Subsequent Mortality and Myocardial Infarction: Insights from the HMO Research Network-Stent Registry

PubMed Central

Valle, Javier A.; Shetterly, Susan; Maddox, Thomas M.; Ho, P. Michael; Bradley, Steven M.; Sandhu, Amneet; Magid, David; Tsai, Thomas T.

2016-01-01

Background Bleeding following hospital discharge from percutaneous coronary intervention (PCI) is associated with increased risk of subsequent myocardial infarction (MI) and death, however the timing of adverse events following these bleeding events is poorly understood. Defining this relationship may help clinicians identify critical periods when patients are at highest risk. Methods and Results All patients undergoing PCI from 2004–2007 who survived to hospital discharge without a bleeding event were identified from the HMO Research Network-Stent Registry. Post-discharge rates and timing of bleeding-related hospitalizations, MI and death were defined. We then assessed the association between post-discharge bleeding-related hospitalizations with death and MI using Cox proportional hazards models. Among 8,137 post-PCI patients surviving to hospital discharge without in-hospital bleeding, 391 (4.8%) suffered bleeding-related hospitalization after discharge, with the highest incidence of bleeding-related hospitalizations occurring within 30 days of discharge (n=79, 20.2%). Post-discharge bleeding-related hospitalization after PCI was associated with subsequent death or MI (hazard ratio [HR] 3.09; 95% confidence interval [CI] 2.41–3.96), with the highest risk for death or MI occurring in the first 60 days after bleeding-related hospitalization (HR 7.16, CI 3.93–13.05). Conclusions Approximately 1 in 20 post-PCI patients are readmitted for bleeding, with the highest incidence occurring within 30 days of discharge. Patients suffering post-discharge bleeding are at increased risk for subsequent death or MI, with the highest risk occurring within the first 60 days following a bleeding-related hospitalization. These findings suggest a critical period after bleeding events when patients are most vulnerable for further adverse events. PMID:27301394

Vortices in high-performance high-temperature superconductors

DOE PAGES

Kwok, Wai-Kwong; Welp, Ulrich; Glatz, Andreas; ...

2016-09-21

The behavior of vortex matter in high-temperature superconductors (HTS) controls the entire electromagnetic response of the material, including its current carrying capacity. In this paper, we review the basic concepts of vortex pinning and its application to a complex mixed pinning landscape to enhance the critical current and to reduce its anisotropy. We focus on recent scientific advances that have resulted in large enhancements of the in-field critical current in state-of-the-art second generation (2G) YBCO coated conductors and on the prospect of an isotropic, high-critical current superconductor in the iron-based superconductors. Finally, we discuss an emerging new paradigm of criticalmore » current by design—a drive to achieve a quantitative correlation between the observed critical current density and mesoscale mixed pinning landscapes by using realistic input parameters in an innovative and powerful large-scale time dependent Ginzburg–Landau approach to simulating vortex dynamics.« less

Superconducting magnetic coil

DOEpatents

Aized, Dawood; Schwall, Robert E.

1999-06-22

A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

Superconducting magnetic coil

DOEpatents

Aized, Dawood; Schwall, Robert E.

1996-06-11

A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

Method for determining transport critical current densities and flux penetration depth in bulk superconductors

NASA Technical Reports Server (NTRS)

Israelsson, Ulf E. (Inventor); Strayer, Donald M. (Inventor)

1992-01-01

A contact-less method for determining transport critical current density and flux penetration depth in bulk superconductor material. A compressor having a hollow interior and a plunger for selectively reducing the free space area for distribution of the magnetic flux therein are formed of superconductor material. Analytical relationships, based upon the critical state model, Maxwell's equations and geometrical relationships define transport critical current density and flux penetration depth in terms of the initial trapped magnetic flux density and the ratio between initial and final magnetic flux densities whereby data may be reliably determined by means of the simple test apparatus for evaluating the current density and flux penetration depth.

Motives for using: a comparison of prescription opioid, marijuana and cocaine dependent individuals.

PubMed

Hartwell, Karen J; Back, Sudie E; McRae-Clark, Aimee L; Shaftman, Stephanie R; Brady, Kathleen T

2012-04-01

Identification of the motives for drug use is critical to the development of effective interventions. Furthermore, consideration of the differences in motives for drug use across substance dependent populations may assist in tailoring interventions. To date, few studies have systematically compared motives for substance use across drug classes. The current study examined motives for drug use between non-treatment seeking individuals with current prescription opioid, marijuana, or cocaine dependence. Participants (N=227) completed the Inventory of Drug-Taking Situations (IDTS; Annis, Turner & Sklar,1997), which contains eight subscales assessing motives for drug use. The findings revealed that prescription opioid dependent individuals scored significantly higher than all other groups on the Physical Discomfort, Testing Personal Control and Conflict with Others subscales. Both the prescription opioid and cocaine dependent groups scored significantly higher than the marijuana group on the Urges or a Temptation to Use subscale. In contrast, marijuana dependent individuals scored highest on the Pleasant Emotions and Pleasant Times with Others subscales. The marked differences revealed in motives for drug use could be used in the development and implementation of specific treatment interventions for prescription opioid, marijuana and cocaine dependent individuals. Published by Elsevier Ltd.

Design and Implementation of an International Nurse Faculty Partnership.

PubMed

Tuxbury, Janis S; Vilton, Yves; Hays, Antoinette; Street, Nancy

2016-01-01

Haiti has the highest rates of infant, under 5 years old, and maternal mortality in the Americas. More nurses are needed throughout the country, but there is a deficit of nursing faculty. Increasing numbers and quality of nursing faculty members will ensure a sustainable, positive impact on the country's nursing profession. The International Nurse Faculty Partnership Initiative was designed to educate a total of 36 current Haitian nurse faculty members at the master's-degree level. The first cohort of 12 nurse faculty members completed the program of study in February 2014, graduating with a master's degree in nursing from the State University of Haiti. Performance evaluation by their respective deans revealed that the Haitian nursing faculty members demonstrated increases in teaching effectiveness and critical thinking in comparison to their premaster's-degree skill levels. The International Nurse Faculty Partnership Initiative expects to graduate a total of 36 master's-level-prepared nurse educators. Currently, program graduates and nursing leaders from Haiti's Ministry of Health are working with the State University of Haiti to establish the faculty of nursing within the institution, creating a system for the ongoing delivery of baccalaureate-level and master-level nursing education within that country. Copyright © 2016 Elsevier Inc. All rights reserved.

Characterization of physico-mechanical properties of Z-phase strengthened ferritic steels using internal friction measurements in the range 25 ÷ 750°C

NASA Astrophysics Data System (ADS)

Kutelia, E. R.; Dzigrashvili, T. A.; Kukava, T. G.; Darsavelidze, G. Sh.; Kurashvili, I. R.; Riedel, H.; Donth, B.

2017-02-01

The present research is dealing with the comparative study of inelastic/elastic behavior of reference ˜12%Cr steel ZL3 and three new trial steels ZU1, ZU2, ZU3, with different ratio of alloying elements and equal content of Cr, using internal friction measurements. The samples were examined in "as-received" condition and after additional electric current tempering at 700˚C under different fixed external mechanical tensions. The values of deformation critical amplitudes for dislocation breakaway (ɛ1) and for microplastic deformation beginning (ɛ2) were determined in addition to the activation energies of relaxation processes in the investigated steels. It is shown that all the three trial steel samples in "as-received" condition exhibit considerably higher values of ɛ2 in comparison to those of reference ZL3 steel. Among them the ZU3 steel has the highest values of ɛ1 and ɛ2, and demonstrates the visible (˜40%) increase in strength characteristics at elevated temperatures (600÷750˚C), achieved by the additional electric current tempering under mechanical tension.

Stimulation effect of electric current density (ECD) on microbial community of a three dimensional particle electrode coupled with biological aerated filter reactor (TDE-BAF).

PubMed

Feng, Yan; Li, Xing; Song, Ting; Yu, Yanzhen; Qi, Jingyao

2017-11-01

Improving the stimulation effect of electric current density (ECD) on microbial community is critical in designing and operating TDE-BAF. This study investigated the effect of ECD at 0.00, 4.08, 6.12, 12.20, 14.25, 16.30 and 20.20A·m -2 on the removal performance, diversity and structure of microbial community in TDE-BAF. Results indicated that the ECD of 14.25A·m -2 exhibited the highest COD, TOC and NH 4 + -N average removal rates with 93.33%, 91.26% and 93.87%, respectively; Under high ECD, especially exceeding 14.25A·m -2 , the inhibition of growth and activity because of plasmatorrhexis was in agreement with the sharp biomass decline; there was no significant relation between community richness and diversity and removal efficiency below optimum ECD, while above optimal ECD, it was just the opposite; Microbial communities mainly including Hydrogenophaga, Saprospiraceae_uncultured, Delftia, Enterobacter, Pseudomonas, Pseudoxanthomonas, and Nitrosospira and physicochemical properties well explained the excellent removal performance at the optimum ECD. Copyright © 2017 Elsevier Ltd. All rights reserved.

On-line self-learning time forward voltage prognosis for lithium-ion batteries using adaptive neuro-fuzzy inference system

NASA Astrophysics Data System (ADS)

Fleischer, Christian; Waag, Wladislaw; Bai, Ziou; Sauer, Dirk Uwe

2013-12-01

The battery management system (BMS) of a battery-electric road vehicle must ensure an optimal operation of the electrochemical storage system to guarantee for durability and reliability. In particular, the BMS must provide precise information about the battery's state-of-functionality, i.e. how much dis-/charging power can the battery accept at current state and condition while at the same time preventing it from operating outside its safe operating area. These critical limits have to be calculated in a predictive manner, which serve as a significant input factor for the supervising vehicle energy management (VEM). The VEM must provide enough power to the vehicle's drivetrain for certain tasks and especially in critical driving situations. Therefore, this paper describes a new approach which can be used for state-of-available-power estimation with respect to lowest/highest cell voltage prediction using an adaptive neuro-fuzzy inference system (ANFIS). The estimated voltage for a given time frame in the future is directly compared with the actual voltage, verifying the effectiveness and accuracy of a relative voltage prediction error of less than 1%. Moreover, the real-time operating capability of the proposed algorithm was verified on a battery test bench while running on a real-time system performing voltage prediction.

Application of Abrasive-Waterjets for Machining Fatigue-Critical Aircraft Aluminum Parts

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

Liu, H T; Hovanski, Yuri; Dahl, Michael E

2010-08-19

Current specifications require AWJ-cut aluminum parts for fatigue critical aerospace structures to go through subsequent processing due to concerns of degradation in fatigue performance. The requirement of secondary process for AWJ-machined parts greatly negates the cost effectiveness of waterjet technology. Some cost savings are envisioned if it can be shown that AWJ net cut parts have comparable durability properties as those conventionally machined. To revisit and upgrade the specifications for AWJ machining of aircraft aluminum, “Dog-bone” specimens, with and without secondary processes, were prepared for independent fatigue tests at Boeing and Pacific Northwest National Laboratory (PNNL). Test results show thatmore » the fatigue life is proportional to quality levels of machined edges or inversely proportional to the surface roughness Ra . Even at highest quality level, the average fatigue life of AWJ-machined parts is about 30% shorter than those of conventionally machined counterparts. Between two secondary processes, dry-grit blasting with aluminum oxide abrasives until the striation is removed visually yields excellent result. It actually prolongs the fatigue life of parts at least three times higher than that achievable with conventional machining. Dry-grit blasting is relatively simple and inexpensive to administrate and, equally important, alleviates the concerns of garnet embedment.« less

The transverse stress effect on the critical current of jelly-roll multifilamentary Nb sub 3 Al wires

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

Zeritis, D.; Iwasa, Y.; Ando, T.

This paper reports on experiments conducted to determine the effect of transverse compressive stress (TCS) on the critical current of jelly-roll multifilamentary Nb{sub 3}Al wire (0.8-mm dia.) for magnetic flux densities up to 12 T. For comparison, identical experiments were performed for bronze-process Ti-alloyed multifilamentary Nb{sub 3}Sn wire (1.0-mm dia.). Although the unstressed critical current density of Nb{sub 3}Al was inferior to that of (NbTi){sub 3}Sn at high fields, under applied TCS Nb{sub 3}Al exhibited less critical current degradation than (NbTi){sub 3}Sn. For example, at 12 T and 150 MPa, TCS-induced critical current degradation was approximately 20% for Nb{sub 3}Al,more » whereas it was approximately 65% for (NbTi){sub 3}Sn. There is optimism that Nb{sub 3}Al will evolve into a useful superconductor for large-scale, high-field applications.« less

Crack problem in superconducting cylinder with exponential distribution of critical-current density

NASA Astrophysics Data System (ADS)

Zhao, Yufeng; Xu, Chi; Shi, Liang

2018-04-01

The general problem of a center crack in a long cylindrical superconductor with inhomogeneous critical-current distribution is studied based on the extended Bean model for zero-field cooling (ZFC) and field cooling (FC) magnetization processes, in which the inhomogeneous parameter η is introduced for characterizing the critical-current density distribution in inhomogeneous superconductor. The effect of the inhomogeneous parameter η on both the magnetic field distribution and the variations of the normalized stress intensity factors is also obtained based on the plane strain approach and J-integral theory. The numerical results indicate that the exponential distribution of critical-current density will lead a larger trapped field inside the inhomogeneous superconductor and cause the center of the cylinder to fracture more easily. In addition, it is worth pointing out that the nonlinear field distribution is unique to the Bean model by comparing the curve shapes of the magnetization loop with homogeneous and inhomogeneous critical-current distribution.

Recovery of Palm Oil and Valuable Material from Oil Palm Empty Fruit Bunch by Sub-critical Water.

PubMed

Ahmad Kurnin, Nor Azrin; Shah Ismail, Mohd Halim; Yoshida, Hiroyuki; Izhar, Shamsul

2016-01-01

Oil palm empty fruit bunch (EFB) is one of the solid wastes produced in huge volume by palm oil mill. Whilst it still contains valuable oil, approximately 22.6 million tons is generated annually and treated as solid waste. In this work, sub-critical water (sub-cw) was used to extract oil, sugar and tar from spikelet of EFB. The spikelet was treated with sub-cw between 180-280°C and a reaction time of 2 and 5 minutes. The highest yield of oil was 0.075 g-oil/g-dry EFB, obtained at 240°C and reaction time of 5 minutes. Astonishingly, oil that was extracted through this method was 84.5% of that obtained through Soxhlet method using hexane. Yield of oil extracted was strongly affected by the reaction temperature and time. Higher reaction temperature induces the dielectric constant of water towards the non-polar properties of solvent; thus increases the oil extraction capability. Meanwhile, the highest yield of sugar was 0.20 g-sugar/g-dry EFB obtained at 220°C. At this temperature, the ion product of water is high enough to enable maximum sub-critical water hydrolysis reaction. This study showed that oil and other valuable material can be recovered using water at sub-critical condition, and most attractive without the use of harmful organic solvent.

Enhanced critical currents in (Gd,Y)Ba2Cu3Ox superconducting tapes with high levels of Zr addition

NASA Astrophysics Data System (ADS)

Selvamanickam, V.; Chen, Y.; Shi, T.; Liu, Y.; Khatri, N. D.; Liu, J.; Yao, Y.; Xiong, X.; Lei, C.; Soloveichik, S.; Galstyan, E.; Majkic, G.

2013-03-01

The critical current and structural properties of (Gd,Y)BaCuO tapes made by metal organic chemical vapor deposition (MOCVD) with Zr addition levels up to 30 at.% have been investigated. The reduction in critical current beyond the previously optimized Zr addition level of 7.5 at.% was found to be due to structural deterioration of the (Gd,Y)Ba2Cu3Ox film. By a modified MOCVD process, enhanced critical current densities have been achieved with high levels of Zr addition, including 3.83 MA cm-2 in 15 at.% Zr-added 1.1 μm thick film at 77 K in zero magnetic field. Critical currents as high as 1072 A/12 mm have been reached in (Gd,Y)BaCuO tapes with 15 at.% Zr addition at 30 K in a field of 3 T applied perpendicular to the tape, corresponding to a pinning force value of 268 GN m-3. The enhanced critical currents achievable with a high density of nanoscale defects by employing high levels of second-phase additions enable the performance targets needed for the use of HTS tapes in coil applications involving high magnetic fields at temperatures below 50 K to be met.

Effect of fatigue loading on critical current in stainless steel-laminated DI-BSCCO superconducting composite tape

NASA Astrophysics Data System (ADS)

Hojo, M.; Osawa, K.; Adachi, T.; Inoue, Y.; Osamura, K.; Ochiai, S.; Ayai, N.; Hayashi, K.

2010-11-01

Tensile strain tolerance of the critical current in (Bi,Pb)2Sr2Ca2Cu3Ox (Bi2223) composite superconductor is dramatically improved when the tape is laminated with stainless steel. For practical applications, it is important to understand whether this reinforcement by lamination is effective under fatigue loading. In the present study, we carried out fatigue tests in LN2 and measured the critical current at the specific fatigue cycles to clarify the strain tolerance of the critical current in stainless steel-laminated drastically innovative Bi2223 (DI-BSCCO®) tapes. The fatigue tests were carried out using a computer-controlled 10 kN servo-hydraulic fatigue testing machine with a load cell capacity of 2.5 kN. Tests under static loading showed that the irreversible stress at which the critical current is reduced by 1% from the original value (tensile stress at Ic/Ic0 = 0.99) was 315 MPa when measured at unloading state. The present fatigue tests results indicated that the critical current was maintained at over 98% of the original value at unloading state after stress cycles of 106 when the static irreversible stress was selected as the maximum stress under fatigue loading. Thus, laminated DI-BSCCO tapes showed excellent mechanical properties even under fatigue loading.

Using Satellite Data to Unpack Causes of Yield Gaps in India's Wheat Belt

NASA Astrophysics Data System (ADS)

Jain, M.; Singh, B.; Srivastava, A.; Malik, R. K.; McDonald, A.; Lobell, D. B.

2016-12-01

India will face significant food security challenges in the coming decades due to climate change, natural resource degradation, and population growth. Yields of wheat, one of India's staple crops, are already stagnating and will be significantly impacted by warming temperatures. Despite these challenges, wheat yields can be enhanced by implementing improved management in regions with existing yield gaps. To identify the magnitude and causes of current yield gaps, we produced 30 m resolution yield maps across India's main wheat belt, the Indo-Gangetic Plains (IGP), from 2000 to 2015. Yield maps were derived using a new method that translates satellite vegetation indices to yield estimates using crop model simulations, bypassing the need for ground calibration data that rarely exist in smallholder systems. We find that yields can be increased by 5% on average and up to 16% in the eastern IGP by improving management to current best practices within a given district. However, if policies and technologies are put in place to improve management to current best practices in Punjab, the highest yielding state, yields can be increased by 29% in the eastern IGP. Considering which factors most influence wheat yields, we find that later sow dates and warmer temperatures are most associated with low yields across the IGP. This suggests that strategies that reduce the negative effects of heat stress, like earlier sowing and planting heat-tolerant wheat varieties, are critical to India's current and future food security.

Apparatus and method for critical current measurements

DOEpatents

Martin, Joe A.; Dye, Robert C.

1992-01-01

An apparatus for the measurement of the critical current of a superconductive sample, e.g., a clad superconductive sample, the apparatus including a conductive coil, a means for maintaining the coil in proximity to a superconductive sample, an electrical connection means for passing a low amplitude alternating current through the coil, a cooling means for maintaining the superconductive sample at a preselected temperature, a means for passing a current through the superconductive sample, and, a means for monitoring reactance of the coil, is disclosed, together with a process of measuring the critical current of a superconductive material, e.g., a clad superconductive material, by placing a superconductive material into the vicinity of the conductive coil of such an apparatus, cooling the superconductive material to a preselected temperature, passing a low amplitude alternating current through the coil, the alternating current capable of generating a magnetic field sufficient to penetrate, e.g., any cladding, and to induce eddy currents in the superconductive material, passing a steadily increasing current through the superconductive material, the current characterized as having a different frequency than the alternating current, and, monitoring the reactance of the coil with a phase sensitive detector as the current passed through the superconductive material is steadily increased whereby critical current of the superconductive material can be observed as the point whereat a component of impedance deviates.

Microstructural and crystallographic imperfections of MgB2 superconducting wire and their correlation with the critical current density

NASA Astrophysics Data System (ADS)

Shahabuddin, Mohammed; Alzayed, Nasser S.; Oh, Sangjun; Choi, Seyong; Maeda, Minoru; Hata, Satoshi; Shimada, Yusuke; Hossain, Md Shahriar Al; Kim, Jung Ho

2014-01-01

A comprehensive study of the effects of structural imperfections in MgB2 superconducting wire has been conducted. As the sintering temperature becomes lower, the structural imperfections of the MgB2 material are increased, as reflected by detailed X-ray refinement and the normal state resistivity. The crystalline imperfections, caused by lattice disorder, directly affect the impurity scattering between the π and σ bands of MgB2, resulting in a larger upper critical field. In addition, low sintering temperature keeps the grain size small, which leads to a strong enhancement of pinning, and thereby, enhanced critical current density. Owing to both the impurity scattering and the grain boundary pinning, the critical current density, irreversibility field, and upper critical field are enhanced. Residual voids or porosities obviously remain in the MgB2, however, even at low sintering temperature, and thus block current transport paths.

Superconducting, magnetic and magnetotransport properties of FeTe1-xSex single crystals

NASA Astrophysics Data System (ADS)

Kumar, Rohit; Sudesh, Varma, G. D.

2018-05-01

The single crystalline samples with compositions FeTe1-xSex (0.25 ≤ x ≤ 0.50) have been prepared via self-flux method and the superconducting, magnetic and magnetotransport properties of the grown crystals were investigated. The superconducting onset temperatures have been determined from the measurements of zero field cooled magnetization and resistance with temperatures. In the present case, highest superconducting transition temperature TC (onset) ˜ 15 K has been obtained for x=0.5. The HC2 (T=0 K) values have been estimated by fitting the experimental HC2 - T plots with WHH model. The highest HC2(0) has been obtained for x=0.5. The activation energy of the thermally activated flux flow has been found from the broadening of superconducting transition in an applied magnetic field using the Arrhenius law. Our results show that the activation energy (U0) decreases with the increasing magnetic field. Furthermore, the magnetization measurements for x=0.4 and 0.5 samples have been performed at T=5 K in the magnetic field range ±7 T to estimate critical current density at different applied magnetic fields using Bean formula. We see that the sample x=0.5 has higher values of JC as compared to that of x=0.4 at all magnetic fields. This is in conformity with the behavior of U0-H plots.

LH launcher Arcs Formation and Detection on JET

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

Baranov, Yu. F.; Challis, C. D.; Kirov, K.

2011-12-23

Mechanisms of arc formation have been analyzed and the critical electric fields for the multipactor effect calculated, compared to the experimental values and found to be within the normal operational space of the LH system on JET. It has been shown that the characteristic electron energy (20-1000)eV for the highest multipactor resonances (N = 4-9) are within the limits of secondary electron yield above 1 required for multipactoring. Electrons with these energies provide the highest gas desorption efficiency when hitting the waveguide walls. The effect of higher waveguide modes and magnetic field on the multipactor was also considered. The distributionmore » function for electrons accelerated by LH waves in front of the launcher has been calculated. The field emission currents have been estimated and found to be small. It is proposed that emission of Fel5, 16 lines, which can be obtained with improved diagnostics, could be used to detect arcs that are missed by a protection system based on the reflected power. The reliability and time response of these signals are discussed. A similar technique based on the observation of the emission of low ionized atoms can be used for a fast detection of other undesirable events to avoid sputtering or melting of the plasma facing components such as RF antenna. These techniques are especially powerful if they are based on emission uniquely associated with specific locations and components.« less

Pediatric cryptosporidiosis: An evaluation of health care and societal costs in Peru, Bangladesh and Kenya.

PubMed

Rafferty, Ellen R; Schurer, Janna M; Arndt, Michael B; Choy, Robert K M; de Hostos, Eugenio L; Shoultz, David; Farag, Marwa

2017-01-01

Cryptosporidium is a leading cause of pediatric diarrhea in resource-limited settings; yet, few studies report the health care costs or societal impacts of this protozoan parasite. Our study examined direct and indirect costs associated with symptomatic cryptosporidiosis in infants younger than 12 months in Kenya, Peru and Bangladesh. Inputs to the economic burden model, such as disease incidence, population size, health care seeking behaviour, hospital costs, travel costs, were extracted from peer-reviewed literature, government documents, and internationally validated statistical tools for each country. Indirect losses (i.e. caregiver income loss, mortality, and growth faltering) were also estimated. Our findings suggest that direct treatment costs per symptomatic cryptosporidiosis episode were highest in Kenya ($59.01), followed by Peru ($23.32), and Bangladesh ($7.62). The total annual economic impacts for the 0-11 month cohorts were highest in Peru ($41.5M; range $0.88-$599.3M), followed by Kenya ($37.4M; range $1.6-$804.5M) and Bangladesh ($9.6M, range $0.28-$91.5M). For all scenarios, indirect societal costs far outweighed direct treatment costs. These results highlight the critical need for innovative improvements to current prevention, diagnostic and treatment strategies available in resource poor settings, as well as the need for solutions that span multiple disciplines including food and water safety, sanitation and livestock production.

Pediatric cryptosporidiosis: An evaluation of health care and societal costs in Peru, Bangladesh and Kenya

PubMed Central

Arndt, Michael B.; Choy, Robert K. M.; de Hostos, Eugenio L.; Shoultz, David; Farag, Marwa

2017-01-01

Cryptosporidium is a leading cause of pediatric diarrhea in resource-limited settings; yet, few studies report the health care costs or societal impacts of this protozoan parasite. Our study examined direct and indirect costs associated with symptomatic cryptosporidiosis in infants younger than 12 months in Kenya, Peru and Bangladesh. Inputs to the economic burden model, such as disease incidence, population size, health care seeking behaviour, hospital costs, travel costs, were extracted from peer-reviewed literature, government documents, and internationally validated statistical tools for each country. Indirect losses (i.e. caregiver income loss, mortality, and growth faltering) were also estimated. Our findings suggest that direct treatment costs per symptomatic cryptosporidiosis episode were highest in Kenya ($59.01), followed by Peru ($23.32), and Bangladesh ($7.62). The total annual economic impacts for the 0–11 month cohorts were highest in Peru ($41.5M; range $0.88-$599.3M), followed by Kenya ($37.4M; range $1.6-$804.5M) and Bangladesh ($9.6M, range $0.28-$91.5M). For all scenarios, indirect societal costs far outweighed direct treatment costs. These results highlight the critical need for innovative improvements to current prevention, diagnostic and treatment strategies available in resource poor settings, as well as the need for solutions that span multiple disciplines including food and water safety, sanitation and livestock production. PMID:28832624

Intensive Care and its Discontents: Psychiatric Illness in the Critically Ill.

PubMed

Hashmi, Ali M; Han, Jin Y; Demla, Vishal

2017-09-01

Critically ill patients can develop a host of cognitive and psychiatric complaints during their intensive care unit (ICU) stay, many of which persist for weeks or months following discharge from the ICU and can seriously affect their quality of life, including their ability to return to work. This article describes some common psychiatric problems encountered by clinicians in the ICU, including their assessment and management. A comprehensive approach is needed to decrease patient suffering, improve morbidity and mortality, and ensure that critically ill patients can return to the highest quality of life after an ICU stay. Copyright © 2017 Elsevier Inc. All rights reserved.

Superconducting critical fields of alkali and alkaline-earth intercalates of MoS2

NASA Technical Reports Server (NTRS)

Woollam, J. A.; Somoano, R. B.

1976-01-01

Results are reported for measurements of the critical-field anisotropy and temperature dependence of group-VIB semiconductor MoS2 intercalated with the alkali and alkaline-earth metals Na, K, Rb, Cs, and Sr. The temperature dependences are compared with present theories on the relation between critical field and transition temperature in the clean and dirty limits over the reduced-temperature range from 1 to 0.1. The critical-field anisotropy data are compared with predictions based on coupled-layers and thin-film ('independent-layers') models. It is found that the critical-field boundaries are steep in all cases, that the fields are greater than theoretical predictions at low temperatures, and that an unusual positive curvature in the temperature dependence appears which may be related to the high anisotropy of the layer structure. The results show that materials with the largest ionic intercalate atom diameters and hexagonal structures (K, Rb, and Cs compounds) have the highest critical temperatures, critical fields, and critical-boundary slopes; the critical fields of these materials are observed to exceed the paramagnetic limiting fields.

Influence of field dependent critical current density on flux profiles in high Tc superconductors

NASA Technical Reports Server (NTRS)

Takacs, S.

1990-01-01

The field distribution for superconducting cylinders and slabs with field dependent critical current densities in combined DC and AC magnetic fields and the corresponding magnetic fluxes are calculated. It is shown that all features of experimental magnetic-field profile measurements can be explained in the framework of field dependent critical current density. Even the quantitative agreement between the experimental and theoretical results using Kim's model is very good.

Superconducting magnetic coil

DOEpatents

Aized, D.; Schwall, R.E.

1999-06-22

A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil. 15 figs.

The Critical Events Interview Manual.

ERIC Educational Resources Information Center

Avery, Donna M.; Taubert, Alexis

This guide for counselors describes the Critical Events Interview (CEI), a new counseling technique designed to be used with women in transition. The concept of critical events and their influence on adult development is described and the history and current status of the CEI are reviewed, along with current results of CEI evaluations and…

Ecological importance of the Southern Boundary of the Antarctic Circumpolar Current

NASA Astrophysics Data System (ADS)

Tynan, Cynthia T.

1998-04-01

The Southern Ocean surrounds the Antarctic continent and supports one of the most productive marine ecosystems. Migratory and endemic species of whales, seals and birds benefit from the high biomass of their principal prey, krill (Euphausia superba) and cephalopods, in this area. Most species of baleen whales and male sperm whales in the Southern Hemisphere migrate between low-latitude breeding grounds in winter and highly productive Antarctic feeding grounds in summer. Here I show the importance of the southernmost reaches of the strongest ocean current, the Antarctic Circumpolar Current (ACC), to a complex and predictable food web of the Southern Ocean. The circumpolar distributions of blue, fin and humpback whales from spring to midsummer trace the non-uniform high-latitude penetration of shoaled, nutrient-rich Upper Circumpolar Deep Water, which is carried eastward by the ACC. The poleward extent of this water mass delineates the Southern Boundary of the ACC and corresponds not only to the circumpolar distributions of baleen whales, but also to distributions of krill and to regions of high, seasonally averaged, phytoplankton biomass. Sperm whales, which feed on cephalopods, also congregate in highest densities near the Southern Boundary. The association of primary production, Krill, and whales with the Southern Boundary, suggests that it provides predictably productive foraging for many species, and is of critical importance to the function of the Southern Ocean ecosystem.

A Needs Assessment of Brain Death Education in Pediatric Critical Care Medicine Fellowships.

PubMed

Ausmus, Andrew M; Simpson, Pippa M; Zhang, Liyun; Petersen, Tara L

2018-04-12

To assess the current training in brain death examination provided during pediatric critical care medicine fellowship. Internet-based survey. United States pediatric critical care medicine fellowship programs. Sixty-four pediatric critical care medicine fellowship program directors and 230 current pediatric critical care medicine fellows/recent graduates were invited to participate. Participants were asked demographic questions related to their fellowship programs, training currently provided at their fellowship programs, previous experience with brain death examinations (fellows/graduates), and perceptions regarding the adequacy of current training. Twenty-nine program directors (45%) and 91 current fellows/graduates (40%) responded. Third-year fellows reported having performed a median of five examinations (interquartile range, 3-6). On a five-point Likert scale, 93% of program directors responded they "agree" or "strongly agree" that their fellows receive enough instruction on performing brain death examinations compared with 67% of fellows and graduates (p = 0.007). The responses were similar when asked about opportunity to practice brain death examinations (90% vs 54%; p < 0.001). In a regression tree analysis, number of brain death examinations performed was the strongest predictor of trainee satisfaction. Both fellows and program directors preferred bedside demonstration or simulation as educational modalities to add to the fellowship curriculum. Pediatric critical care medicine fellows overall perform relatively few brain death examinations during their training. Pediatric critical care medicine fellows and program directors disagree in their perceptions of the current training in brain death examination, with fellows perceiving a need for increased training. Both program directors and fellows prefer additional training using bedside demonstration or simulation. Since clinical exposure to brain death examinations is variable, adding simulated brain death examinations to the pediatric critical care medicine fellowship curriculum could help standardize the experience.

The Reduction of the Critical Currents in Nb3Sn Cables under Transverse Loads

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

Van Oort, J.M.; Scanlan, R.M.; Weijers, H.W.

1992-08-01

The degradation of the critical current of impregnated Rutherford type Nb{sub 3}Sn cables is investigated as a function of the applied transverse load and magnetic field. The cable is made of TWCA modified jelly-roll type strand material and has a keystone angle of 1.0 degree. The voltage-current characteristics are determined for the magnetic field ranging from 2 to 11 tesla and transverse pressure up to 250 MPa on the cable surface. It is found that the 48-strand cable, made of strands with 6 elements in the matrix, shows a larger critical current degradation than the 26-strand cable with 36 elementsmore » per strand. The global degradation of the 48-strand cable is 63% at 150 MPa, and 40% at 150 MPa for the 26-strand cable. Micro-analysis of the cross-section shows permanent damage to the sharp edge of the cable. The influence of the keystone angle on the critical-current degradation is currently under investigation.« less

A Comprehensive Critique and Review of Published Measures of Acne Severity

PubMed Central

Furber, Gareth; Leach, Matthew; Segal, Leonie

2016-01-01

Objective: Acne vulgaris is a dynamic, complex condition that is notoriously difficult to evaluate. The authors set out to critically evaluate currently available measures of acne severity, particularly in terms of suitability for use in clinical trials. Design: A systematic review was conducted to identify methods used to measure acne severity, using MEDLINE, CINAHL, Scopus, and Wiley Online. Each method was critically reviewed and given a score out of 13 based on eight quality criteria under two broad groupings of psychometric testing and suitability for research and evaluation. Results: Twenty-four methods for assessing acne severity were identified. Four scales received a quality score of zero, and 11 scored ≤3. The highest rated scales achieved a total score of 6. Six scales reported strong inter-rater reliability (ICC>0.75), and four reported strong intra-rater reliability (ICC>0.75). The poor overall performance of most scales, largely characterized by the absence of reliability testing or evidence for independent assessment and validation indicates that generally, their application in clinical trials is not supported. Conclusion: This review and appraisal of instruments for measuring acne severity supports previously identified concerns regarding the quality of published measures. It highlights the need for a valid and reliable acne severity scale, especially for use in research and evaluation. The ideal scale would demonstrate adequate validation and reliability and be easily implemented for third-party analysis. The development of such a scale is critical to interpreting results of trials and facilitating the pooling of results for systematic reviews and meta-analyses. PMID:27672410

Production and Characterization of Bulk MgB2 Material made by the Combination of Crystalline and Carbon Coated Amorphous Boron Powders

NASA Astrophysics Data System (ADS)

Hiroki, K.; Muralidhar, M.; Koblischka, M. R.; Murakami, M.

2017-07-01

The object of this investigation is to reduce the cost of bulk production and in the same time to increase the critical current performance of bulk MgB2 material. High-purity commercial powders of Mg metal (99.9% purity) and two types of crystalline (99% purity) and 16.5 wt% carbon-coated, nanometer-sized amorphous boron powders (98.5% purity) were mixed in a nominal composition of MgB2 to reduce the boron cost and to see the effect on the superconducting and magnetic properties. Several samples were produced mixing the crystalline boron and carbon-coated, nanometer-sized amorphous boron powders in varying ratios (50:50, 60:40, 70:30, 80:20, 90:10) and synthesized using a single-step process using the solid state reaction around 800 °C for 3 h in pure argon atmosphere. The magnetization measurements exhibited a sharp superconducting transition temperature with T c, onset around 38.6 K to 37.2 K for the bulk samples prepared utilizing the mixture of crystalline boron and 16.5% carbon-coated amorphous boron. The critical current density at higher magnetic field was improved with addition of carbon-coated boron to crystalline boron in a ratio of 80:20. The highest self-field Jc around 215,000 A/cm2 and 37,000 A/cm2 were recorded at 20 K, self-field and 2 T for the sample with a ratio of 80:10. The present results clearly demonstrate that the bulk MgB2 performance can be improved by adding carbon-coated nano boron to crystalline boron, which will be attractive to reduce the cost of bulk MgB2 material for several industrial applications.

High-Pressure Oxygenation of Mt-Ybco the way to Reduce the Oxygenation Time, to Prevent Macrocracking, and to Obtain Materials with High Critical Currents.

NASA Astrophysics Data System (ADS)

Prikhna, T. A.; Chaud, X.; Gawalek, W.; Joulain, A.; Rabier, J.; Moshchil, V. E.; Savchuk, Ya. M.; Sergienko, N. V.; Dub, S. N.; Melnikov, V. S.; Habisreuther, T.; Litzkendorf, D.; Bierlich, J.

2008-03-01

The oxygenation of MT-YBCO under isostatic oxygen pressure (up to 16 MPa) at 900-800 °C allowed reduced process time, lower macrocracking, and reduced microcracks. Additionally higher critical currents, trapped fields and mechanical characteristics can be attained. At 77 K thin-walled MT-YBCO had a jc in the ab plane of 85 kA/cm2 at 0 T and higher than 10 kA/cm2 in fields up to 5 T and the irreversibility field was 9.8 T. In the c-direction jc was 34 kA/cm2 in 0 T and higher than 2.5 kA/cm2 in a 10 T field. At 4.9 N-load the micohardness, Hv, was 8.7±0.3 GPa in the ab-plane and 7.6±0.3 GPa in the c-direction. The fracture toughness, K1C, was 2.5±0.1 MPaṡm0.5 (ab-plane) and 2.8±0.24 MPaṡm0.5 (c-direction). The samples with a higher twin density demonstrated a higher jc, especially in applied magnetic field. The twin density correlates with the sizes and distribution of Y211 grains in Y123. The thin-walled ceramics that demonstrated the highest jc contained about 22 twins in 1 μm and were practically free from dislocations and stacking faults. The maximal trapped field of the block of thin-walled ceramic oxygenated at 900-800 °C and 16 MPa was doubled as compared to that oxygenated at low temperature under ambient pressure.

Vortex pinning in ferromagnet-superconductor bilayer with tunable domain patterns

NASA Astrophysics Data System (ADS)

Cieplak, Marta Z.

2011-03-01

Ferromagnet superconductor hybrids provide a fascinating example of systems in which there is a rich interplay between two seemingly incompatible collective phenomena. Particularly interesting is the impact of the ferromagnet on the dynamics of vortices in the superconductor. The magnetic domains control the location of the vortices. Exquisite control of the dynamics can be achieved by careful tuning of the geometry of the magnetic domains. In this talk I will present the results of recent experiments on superconductor(S)-ferromagnet(F) bilayers with a focus on understanding the hitherto unexplained seemingly unpredictable dependence of the critical current density on the parameters of the experiment. In our experiments the S layer is made of niobium, the F layer is a Co/Pt multilayer with perpendicular magnetic anisotropy, and a thin insulating layer in-between eliminates proximity effect. We use various demagnetization procedures to define different domain patterns in the F layer. We show that some domain patterns produce highly inhomogeneous flux penetration and strong vortex confinement at the sample edge, while for others there is remerkable enhancement of the critical current density in excess of 15. This is the highest value reported to date. We have measured, for the first time in a single tunable structure, the dependence of the activation energy for vortex pinning on the domain width, temperature, and magnetic field. In collaboration with L.Y. Zhu, X. M. Cheng and C. L. Chien (Johns Hopkins), Z. Adamus (Polish Acad. Sci.) and M. Konczykowski (Ecole Polytechnique). Supported by NSF grant DMR05-20491, by the French-Polish Program PICS 4916, and by EU within the European Regional Development Fund, through the Innovative Economy grant POIG.01.01.02-00-108/09.

Strong flux pinning at 4.2 K in SmBa2Cu3O y coated conductors with BaHfO3 nanorods controlled by low growth temperature

NASA Astrophysics Data System (ADS)

Miura, S.; Tsuchiya, Y.; Yoshida, Y.; Ichino, Y.; Awaji, S.; Matsumoto, K.; Ibi, A.; Izumi, T.

2017-08-01

In order to apply REBa2Cu3O y (REBCO, RE = rare earth elements or Y) coated conductors in high magnetic field, coil-based applications, the isotropic improvement of their critical current performance with respect to the directions of the magnetic field under these operating conditions is required. Most applications operate at temperatures lower than 50 K and magnetic fields over 2 T. In this study, the improvement of critical current density (J c) performance for various applied magnetic field directions was achieved by controlling the nanostructure of the BaHfO3 (BHO)-doped SmBa2Cu3O y (SmBCO) films on metallic substrates. The corresponding minimum J c value of the films at 40 K under an applied 3 T field was 5.2 MA cm-2, which is over ten times higher than that of a fully optimized Nb-Ti wire at 4.2 K. At 4.2 K, under a 17.5 T field, a flux pinning force density of 1.4 TN m-3 for B//c was realized; this value is among the highest values reported for REBCO films to date. More importantly, the F p for B//c corresponds to the minimum value for various applied magnetic field directions. We investigated the dominant flux pinning centers of films at 4.2 K using the anisotropic scaling approach based on the effective mass model. The dominant flux pinning centers are random pinning centers at 4.2 K, i.e., a high pinning performance was achieved by the high number density of random pins in the matrix of the BHO-doped SmBCO films.

Enhancing superconducting critical current by randomness

DOE PAGES

Wang, Y. L.; Thoutam, L. R.; Xiao, Z. L.; ...

2016-01-11

The key ingredient of high critical currents in a type-II superconductor is defect sites that pin vortices. Here, we demonstrate that a random pinscape, an overlooked pinning system in nanopatterned superconductors, can lead to a substantially larger critical current enhancement at high magnetic fields than an ordered array of vortex pin sites. We reveal that the better performance of a random pinscape is due to the variation of the local density of its pinning sites, which mitigates the motion of vortices. This is confirmed by achieving even higher enhancement of the critical current through a conformally mapped random pinscape, wheremore » the distribution of the local density of pinning sites is further enlarged. Our findings highlight the potential of random pinscapes in enhancing the superconducting critical currents of applied superconductors in which random pin sites of nanoscale defects emerging in the materials synthesis process or through ex-situ irradiation are the only practical choice for large-scale production. Our results may also stimulate research on effects of a random pinscape in other complementary systems such as colloidal crystals, Bose-Einstein condensates, and Luttinger liquids.« less

Experiments with planar inductive ion source meant for creation of H+ beams.

PubMed

Vainionpaa, J H; Kalvas, T; Hahto, S K; Reijonen, J

2007-06-01

In this article the effects of different engineering parameters of rf-driven ion sources with an external spiral antenna and a quartz rf window are studied. This article consists of three main topics: the effect of source geometry on the operation gas pressure, the effect of source materials and magnetic confinement on extracted current density and ion species, and the effect of different antenna geometries on the extracted current density. The effect of source geometry was studied using three cylindrical plasma chambers with different inner diameters. The chamber materials were studied using two materials, aluminum (Al) and alumina (Al(2)O(3)). The removable 14 magnet multicusp confinement arrangement enabled us to compare the effects of the two wall materials with and without the magnetic confinement. The highest measured proton fractions were measured using Al(2)O(3) plasma chamber and no multicusp confinement. For the compared ion sources the source with multicusp confinement and Al(2)O(3) plasma chamber yields the highest current densities. Multicusp confinement increased the maximum extracted current by up to a factor of 2. Plasma production with different antenna geometries were also studied. The highest current density was achieved using 4.5 loop solenoid antenna with 6.0 cm diameter. A slightly lower current density with lower pressure was achieved using a tightly wound 3 loop spiral antenna with 3.3 cm inner diameter and 6 cm outer diameter.

Development of a 10 m quasi-isotropic strand assembled from 2G wires

NASA Astrophysics Data System (ADS)

Kan, Changtao; Wang, Yinshun; Hou, Yanbing; Li, Yan; Zhang, Han; Fu, Yu; Jiang, Zhe

2018-03-01

Quasi-isotropic strands made of second generation (2G) high temperature superconducting (HTS) wires are attractive to applications of high-field magnets at low temperatures and power transmission cables at liquid nitrogen temperature in virtue of their high current carrying capability and well mechanical property. In this contribution, a 10 m length quasi-isotropic strand is manufactured and successfully tested in liquid nitrogen to verify the feasibility of an industrial scale production of the strand by the existing cabling technologies. The strand with copper sheath consists of 72 symmetrically assembled 2G wires. The uniformity of critical properties of long quasi-isotropic strands, including critical current and n-value, is very important for their using. Critical currents as well as n-values of the strand are measured every 1 m respectively and compared with the simulation results. Critical current and n-value of the strand are calculated basing on the self-consistent model solved by the finite element method (FEM). Effects of self-field on the critical current and n-value distributions in wires of the strand are analyzed in detail. The simulation results show good agreement with the experimental data and the 10 m quasi-isotropic strand has good critical properties uniformity.

Leveraging Terminologies for Retrieval of Radiology Reports with Critical Imaging Findings

PubMed Central

Warden, Graham I.; Lacson, Ronilda; Khorasani, Ramin

2011-01-01

Introduction: Communication of critical imaging findings is an important component of medical quality and safety. A fundamental challenge includes retrieval of radiology reports that contain these findings. This study describes the expressiveness and coverage of existing medical terminologies for critical imaging findings and evaluates radiology report retrieval using each terminology. Methods: Four terminologies were evaluated: National Cancer Institute Thesaurus (NCIT), Radiology Lexicon (RadLex), Systemized Nomenclature of Medicine (SNOMED-CT), and International Classification of Diseases (ICD-9-CM). Concepts in each terminology were identified for 10 critical imaging findings. Three findings were subsequently selected to evaluate document retrieval. Results: SNOMED-CT consistently demonstrated the highest number of overall terms (mean=22) for each of ten critical findings. However, retrieval rate and precision varied between terminologies for the three findings evaluated. Conclusion: No single terminology is optimal for retrieving radiology reports with critical findings. The expressiveness of a terminology does not consistently correlate with radiology report retrieval. PMID:22195212

Higher Education: A Critical Business.

ERIC Educational Resources Information Center

Barnett, Ronald

Current concepts of critical thinking need to be reconstrued into the much broader concept of "critical being" and applied to higher education. Under this construct, critical persons (students) become more than just critical thinkers; they engage critically with the world and with themselves; they not only reflect critically on…

Magnetic field oscillations of the critical current in long ballistic graphene Josephson junctions

NASA Astrophysics Data System (ADS)

Rakyta, Péter; Kormányos, Andor; Cserti, József

2016-06-01

We study the Josephson current in long ballistic superconductor-monolayer graphene-superconductor junctions. As a first step, we have developed an efficient computational approach to calculate the Josephson current in tight-binding systems. This approach can be particularly useful in the long-junction limit, which has hitherto attracted less theoretical interest but has recently become experimentally relevant. We use this computational approach to study the dependence of the critical current on the junction geometry, doping level, and an applied perpendicular magnetic field B . In zero magnetic field we find a good qualitative agreement with the recent experiment of M. Ben Shalom et al. [Nat. Phys. 12, 318 (2016), 10.1038/nphys3592] for the length dependence of the critical current. For highly doped samples our numerical calculations show a broad agreement with the results of the quasiclassical formalism. In this case the critical current exhibits Fraunhofer-like oscillations as a function of B . However, for lower doping levels, where the cyclotron orbit becomes comparable to the characteristic geometrical length scales of the system, deviations from the results of the quasiclassical formalism appear. We argue that due to the exceptional tunability and long mean free path of graphene systems a new regime can be explored where geometrical and dynamical effects are equally important to understand the magnetic field dependence of the critical current.

Orientation and Order in Shear-Aligned Thin Films of Cylinder-Forming Block Copolymers

NASA Astrophysics Data System (ADS)

Register, Richard

The regularity and tunability of the nanoscale structure in block copolymers makes their thin films attractive as nanolithographic templates; however, in the absence of a guiding field, self-assembly produces a polygrain structure with no particular orientation and a high density of defects. As demonstrated in the elegant studies of Ed Kramer and coworkers, graphoepitaxy can provide local control over domain orientation, with a dramatic reduction in defect density. Alternatively, cylindrical microdomains lying in the plane of the film can be aligned over macroscopic areas by applying shear stress at the film surface. In non-sheared films of polystyrene-poly(n-hexylmethacrylate) diblocks, PS-PHMA, the PS cylinder axis orientation relative to the surface switches from parallel to perpendicular as a function of film thickness; this oscillation is damped out as the fraction of the PS block increases, away from the sphere-cylinder phase boundary. In aligned films, thicknesses which possess the highest coverage of parallel cylinders prior to shear show the highest quality of alignment post-shear, as measured by the in-plane orientational order parameter. In well-aligned samples of optimal thickness, the quality of alignment is limited by isolated dislocations, whose density is highest at high PS contents, and by undulations in the cylinders' trajectories, whose impact is most severe at low PS contents; consequently, polymers whose compositions lie in the middle of the cylinder-forming region exhibit the highest quality of alignment. The dynamics of the alignment process are also investigated, and fit to a melting-recrystallization model which allows for the determination of two key alignment parameters: the critical stress needed for alignment, and an orientation rate constant. For films containing a monolayer of cylindrical domains, as PS weight fraction or overall molecular weight increases, the critical stress increases moderately, while the rate of alignment drastically decreases. As the number of layers of cylinders in the film increases, the critical stress decreases modestly, while the rate remains unchanged; substrate wetting condition has no measurable influence on alignment response. [Work of Raleigh Davis, in collaboration with Paul Chaikin.

Critical Decay Index at the Onset of Solar Eruptions

NASA Astrophysics Data System (ADS)

Zuccarello, F. P.; Aulanier, G.; Gilchrist, S. A.

2015-12-01

Magnetic flux ropes are topological structures consisting of twisted magnetic field lines that globally wrap around an axis. The torus instability model predicts that a magnetic flux rope of major radius R undergoes an eruption when its axis reaches a location where the decay index -d({ln}{B}{ex})/d({ln}R) of the ambient magnetic field Bex is larger than a critical value. In the current-wire model, the critical value depends on the thickness and time evolution of the current channel. We use magnetohydrodynamic simulations to investigate whether the critical value of the decay index at the onset of the eruption is affected by the magnetic flux rope’s internal current profile and/or by the particular pre-eruptive photospheric dynamics. The evolution of an asymmetric, bipolar active region is driven by applying different classes of photospheric motions. We find that the critical value of the decay index at the onset of the eruption is not significantly affected by either the pre-erupitve photospheric evolution of the active region or the resulting different magnetic flux ropes. As in the case of the current-wire model, we find that there is a “critical range” [1.3-1.5], rather than a “critical value” for the onset of the torus instability. This range is in good agreement with the predictions of the current-wire model, despite the inclusion of line-tying effects and the occurrence of tether-cutting magnetic reconnection.

Eddy current technique for predicting burst pressure

DOEpatents

Petri, Mark C.; Kupperman, David S.; Morman, James A.; Reifman, Jaques; Wei, Thomas Y. C.

2003-01-01

A signal processing technique which correlates eddy current inspection data from a tube having a critical tubing defect with a range of predicted burst pressures for the tube is provided. The method can directly correlate the raw eddy current inspection data representing the critical tubing defect with the range of burst pressures using a regression technique, preferably an artificial neural network. Alternatively, the technique deconvolves the raw eddy current inspection data into a set of undistorted signals, each of which represents a separate defect of the tube. The undistorted defect signal which represents the critical tubing defect is related to a range of burst pressures utilizing a regression technique.

Flood-inundation maps for North Fork Salt Creek at Nashville, Indiana

USGS Publications Warehouse

Martin, Zachary W.

2017-11-13

Digital flood-inundation maps for a 3.2-mile reach of North Fork Salt Creek at Nashville, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Department of Transportation. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science website at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding that correspond to selected water levels (stages) at the North Fork Salt Creek at Nashville, Ind., streamgage (USGS station number 03371650). Real-time stages at this streamgage may be obtained from the USGS National Water Information System at http://waterdata.usgs.gov/nwis or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also shows observed USGS stages at the same site as the USGS streamgage (NWS site NFSI3).Flood profiles were computed for the stream reach by means of a one-dimensional, step-backwater hydraulic modeling software developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated using the current (2015) stage-discharge rating at the USGS streamgage 03371650, North Fork Salt Creek at Nashville, Ind. The hydraulic model was then used to compute 12 water-surface profiles for flood stages at 1-foot (ft) intervals, except for the highest profile of 22.9 ft, referenced to the streamgage datum ranging from 12.0 ft (the NWS “action stage”) to 22.9 ft, which is the highest stage of the current (2015) USGS stage-discharge rating curve and 1.9 ft higher than the NWS “major flood stage.” The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging data having a 0.98-ft vertical accuracy and 4.9-ft horizontal resolution) to delineate the area flooded at each stage.The availability of these maps, along with information regarding current stage from the USGS streamgage, will provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for postflood recovery efforts.

78 FR 78071 - Protection of Stratospheric Ozone: Adjustments to the Allowance System for Controlling HCFC...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-24

... an individual consumption baseline year to each company by selecting its highest ODP-weighted... 2003-2009 regulatory period, using each company's highest ``production year'' or ``consumption year... 605 based on an EPA determination regarding current scientific information or the availability of...

Green Propulsion Technologies for Advanced Air Transports

NASA Technical Reports Server (NTRS)

Del Rosario, Ruben

2015-01-01

Air transportation is critical to U.S. and Global economic vitality. However, energy and climate issues challenge aviations ability to be sustainable in the long term. Aviation must dramatically reduce fuel use and related emissions. Energy costs to U.S. airlines nearly tripled between 1995 and 2011, and continue to be the highest percentage of operating costs. The NASA Advanced Air Transports Technology Project addresses the comprehensive challenge of enabling revolutionary energy efficiency improvements in subsonic transport aircraft combined with dramatic reductions in harmful emissions and perceived noise to facilitate sustained growth of the air transportation system. Advanced technologies and the development of unconventional aircraft systems offer the potential to achieve these improvements. The presentation will highlight the NASA vision of revolutionary systems and propulsion technologies needed to achieve these challenging goals. Specifically, the primary focus is on the N+3 generation; that is, vehicles that are three generations beyond the current state of the art, requiring mature technology solutions in the 2025-30 timeframe, which are envisioned as being powered by Hybrid Electric Propulsion Systems.

[German general and visceral surgery: positioning within the international scientific community].

PubMed

Welsch, T; Wente, M N; Dralle, H; Neuhaus, P; Schumpelick, V; Siewert, J R; Büchler, M W

2010-04-01

Assessment of scientific performance is critical for selection committees and research funding. The present work evaluated the standing of German surgical research within the international community. A database analysis was performed in December 2009 using the ISI Web of Science. The highest impact factor of surgical journals is currently 8.460 with a median impact of all journals of 1.369. Leading academic surgeons have an h-index of more than 60. German surgeons are within the top five leading researchers in the fields of surgery for esophageal and pancreatic cancer, thyroid, hernia, and liver/kidney transplantation. Among the 50 institutions with most publications on a particular topic, 4-5 German centers are mostly represented. The top positions are in total decisively occupied by leading universities in the USA. On the basis of scientific parameters German surgical research can compete with leading international centers in certain fields, but should aim to increase the overall impact of research by publishing more in journals with above average impact factors.

Performances of BNL high-intensity synchrotrons

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

Weng, W.T.

1998-03-01

The AGS proton synchrotron was completed in 1960 with initial intensity in the 10 to the 10th power proton per pulse (ppp) range. Over the years, through many upgrades and improvements, the AGS now reached an intensity record of 6.3 {times} 10{sup 13} ppp, the highest world intensity record for a proton synchrotron on a single pulse basis. At the same time, the Booster reached 2.2 {times} 10{sup 13} ppp surpassing the design goal of 1.5 {times} 10{sup 13} ppp due to the introduction of second harmonic cavity during injection. The intensity limitation caused by space charge tune spread andmore » its relationship to injection energy at 50 MeV, 200 MeV, and 1,500 MeV will be presented as well as many critical accelerator manipulations. BNL currently participates in the design of an accumulator ring for the SNS project at Oak Ridge. The status on the issues of halo formation, beam losses and collimation are also presented.« less

Microaggressions, diabetes distress, and self-care behaviors in a sample of American Indian adults with type 2 diabetes.

PubMed

Sittner, Kelley J; Greenfield, Brenna L; Walls, Melissa L

2018-02-01

American Indian/Alaska Native people experience the highest age-adjusted prevalence of type 2 diabetes of any racial group in the United States, as well as high rates of related health problems. Chronic stressors such as perceived discrimination are important contributors to these persistent health disparities. The current study used structural equation modeling to examine the relationships between racial microaggressions, diabetes distress, and self-care behaviors (diet and exercise) in a sample of 192 American Indians with type 2 diabetes from the northern United States. We found that microaggressions was positively associated with diabetes distress and that microaggressions had an indirect link to self-care via diabetes distress. Diabetes distress is an important mechanism linking microaggressions to self-care behaviors, which are critical to successful disease management and the reduction of complications. The amelioration of diabetes distress could improve self-care even in the presence of pervasive, chronic social stressors such as microaggressions.

Shear Ram Verification Test Protocol (VTP) Best Practices

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

Lindley, Roy A.; Braun, Joseph C.

A blowout preventer (BOP) is a critical component used on subsea oil and gas wells during drilling, completion, and workover operations on the U. S. outer continental shelf (OCS). The purpose of the BOP is to seal oil and gas wells, and in the case of an emergency well-control event, to prevent the uncontrolled release of hydrocarbons. One of the most important components of the BOP is the hydraulically operated blind shear ram (BSR) that shears drilling-related components, such as drill pipes, casings, tubings, and wire-related tools that may have been placed in the well. In addition to shearing thesemore » components, the BSR must form a seal to keep hydrocarbons within the well bore, even when under the highest well-fluid pressures expected. The purpose of this document is for Argonne National Laboratory (ANL) to provide an independent view, based on current regulations, and best practices for testing and confirming the operability and suitability of BSRs under realistic (or actual) well conditions.« less

Green Propulsion Technologies for Advanced Air Transports

NASA Technical Reports Server (NTRS)

Del Rosario, Ruben

2015-01-01

Air transportation is critical to U.S. and Global economic vitality. However, energy and climate issues challenge aviation's ability to be sustainable in the long term. Aviation must dramatically reduce fuel use and related emissions. Energy costs to U.S. airlines nearly tripled between 1995 and 2011, and continue to be the highest percentage of operating costs. The NASA Advanced Air Transports Technology Project addresses the comprehensive challenge of enabling revolutionary energy efficiency improvements in subsonic transport aircraft combined with dramatic reductions in harmful emissions and perceived noise to facilitate sustained growth of the air transportation system. Advanced technologies and the development of unconventional aircraft systems offer the potential to achieve these improvements. The presentation will highlight the NASA vision of revolutionary systems and propulsion technologies needed to achieve these challenging goals. Specifically, the primary focus is on the N+3 generation; that is, vehicles that are three generations beyond the current state of the art, requiring mature technology solutions in the 2025-30 timeframe.

Characterising primary productivity measurements across a dynamic western boundary current region

NASA Astrophysics Data System (ADS)

Everett, Jason D.; Doblin, Martina A.

2015-06-01

Determining the magnitude of primary production (PP) in a changing ocean is a major research challenge. Thousands of estimates of marine PP exist globally, but there remain significant gaps in data availability, particularly in the Southern Hemisphere. In situ PP estimates are generally single-point measurements and therefore we rely on satellite models of PP in order to scale up over time and space. To reduce the uncertainty around the model output, these models need to be assessed against in situ measurements before use. This study examined the vertically-integrated productivity in four water-masses associated with the East Australian Current (EAC), the major western boundary current (WBC) of the South Pacific. We calculated vertically integrated PP from shipboard 14C PP estimates and then compared them to estimates from four commonly used satellite models (ESQRT, VGPM, VGPM-Eppley, VGPM-Kameda) to assess their utility for this region. Vertical profiles of the water-column show each water-mass had distinct temperature-salinity signatures. The depth of the fluorescence-maximum (fmax) increased from onshore (river plume) to offshore (EAC) as light penetration increased. Depth integrated PP was highest in river plumes (792±181 mg C m-2 d-1) followed by the EAC (534±116 mg C m-2 d-1), continental shelf (140±47 mg C m-2 d-1) and cyclonic eddy waters (121±4 mg C m-2 d-1). Surface carbon assimilation efficiency was greatest in the EAC (301±145 mg C (mg Chl-a)-1 d-1) compared to other water masses. All satellite primary production models tested underestimated EAC PP and overestimated continental shelf PP. The ESQRT model had the highest skill and lowest bias of the tested models, providing the best first-order estimates of PP on the continental shelf, including at a coastal time-series station, Port Hacking, which showed considerable inter-annual variability (155-2957 mg C m-2 d-1). This work provides the first estimates of depth integrated PP associated with the East Australian Current in temperate Australia. The ongoing intensification of all WBCs makes it critical to understand the variability in PP at the regional scale. More accurate predictions in the EAC region will require vertically-resolved in situ productivity and bio-optical measurements across multiple time scales to allow development of other models which simulate dynamic ocean conditions.

Going with the flow: Tidal influence on the occurrence of the harbour porpoise (Phocoena phocoena) in the Marsdiep area, The Netherlands

NASA Astrophysics Data System (ADS)

IJsseldijk, Lonneke L.; Camphuysen, Kees C. J.; Nauw, Janine J.; Aarts, Geert

2015-09-01

One of the most important factors explaining the distribution and behaviour of coastal marine mammals are tides. Tidal forces drive a large number of primary and secondary processes, such as changes in water depth, salinity, temperature, current velocity and direction. Unravelling which tidal process is the most influential for a certain species is often challenging, due to a lack of observations of all tide related covariates, strong correlation between them, and the elusive nature of most marine organisms which often hampers their detection. In the Marsdiep area, a tidal inlet between the North Sea and the Dutch Wadden Sea, the presence of harbour porpoises (Phocoena phocoena) was studied as a function of tide related covariates. Observations were carried out in early spring from a ferry crossing the inlet on a half hourly basis. Environmental and sightings data were collected by one observer, while an on-board Acoustic Doppler Current Profiler (ADCP) and temperature sensor continuously recorded current velocity profiles and temperature, respectively. Sea surface temperature and salinity were measured at a nearby jetty. Sightings (n = 134) were linked to tidal elevation, geographical position, local depth-averaged current velocity, water temperature (with and without trend correction) and salinity. Variation in sighting rate was best described by salinity, with highest sighting rate at high levels of salinity (> 30 g kg- 1), indicating that porpoises enter the area in bodies of (more saline) North Sea water. Second best variable was time of day, with the highest sighting rate early morning, and decreasing during the day. However, surveys in the morning happened to coincide more often with high water and hence, the apparent time of day effect could be due to collinearity. Most porpoises were present in the northern part of the Marsdiep, particularly during high tide. Tide dependent sighting rates confirmed that porpoises reside in the North Sea, and enter the western Wadden Sea during the flood and leave during ebb. This tidal influx is most likely related to prey availability, which corresponds to other recent studies in this area showing higher fish abundance during high tide. Documenting information on tide related patterns could be used in practice, when e.g. planning anthropogenic activities or assessing critical habitats for this species.

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

Selvamanickam, V; Chen, Y; Shi, T

The critical current and structural properties of (Gd,Y)BaCuO tapes made by metal organic chemical vapor deposition (MOCVD) with Zr addition levels up to 30 at.% have been investigated. The reduction in critical current beyond the previously optimized Zr addition level of 7.5 at.% was found to be due to structural deterioration of the (Gd,Y)Ba2Cu3Ox film. By a modified MOCVD process,enhanced critical current densities have been achieved with high levels of Zr addition,including 3.83 MA cm(-2) in 15 at.% Zr- added 1.1 mu m thick film at 77 K in zero magnetic field. Critical currents as high as 1072 A/ 12more » mm have been reached in (Gd,Y) BaCuO tapes with 15 at.% Zr addition at 30 K in a field of 3 T applied perpendicular to the tape,corresponding to a pinning force value of 268 GN m(-3). The enhanced critical currents achievable with a high density of nanoscale defects by employing high levels of second- phase additions enable the performance targets needed for the use of HTS tapes in coil applications involving high magnetic fields at temperatures below 50 K to be met.« less

Maximization of current efficiency for organic pollutants oxidation at BDD, Ti/SnO2-Sb/PbO2, and Ti/SnO2-Sb anodes.

PubMed

Xing, Xuan; Ni, Jinren; Zhu, Xiuping; Jiang, Yi; Xia, Jianxin

2018-08-01

Whereas electrochemical oxidation is noted for its ability to degrade bio-refractory organics, it has also been incorrectly criticized for excessive energy consumption. The present paper rectifies this misunderstanding by demonstrating that the energy actually consumed in the degradation process is much less than that wasted in the side reaction of oxygen evolution. To minimize the side reaction, the possible highest instantaneous current efficiency (PHICE) for electrochemical oxidation of phenol at Boron-doped Diamond (BDD), Ti/SnO 2 -Sb/PbO 2 (PbO 2 ), and Ti/SnO 2 -Sb (SnO 2 ) anodes has been investigated systematically, and found to reach almost 100% at the BDD anode compared with 23% at the PbO 2 anode and 9% at the SnO 2 anode. The significant discrepancy between PHICE values at the various anodes is interpreted in terms of different existing forms of hydroxyl radicals. For each anode system, the PHICEs are maintained experimentally using a computer-controlled exponential decay current mode throughout the electrolysis process. For applications, the minimized energy consumption is predicted by response surface methodology, and demonstrated for the BDD anode system. Consequently, almost 100% current efficiency is achieved (for a relatively meagre energy consumption of 17.2 kWh kgCOD -1 ) along with excellent COD degradation efficiency by optimizing the initial current density, flow rate, electrolysis time, and exponential decay constant. Compared with galvanostatic conditions, over 70% of the energy is saved in the present study, thus demonstrating the great potential of electrochemical oxidation for practical applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

Bewildering Education

ERIC Educational Resources Information Center

Snaza, Nathan

2013-01-01

Theorists as diverse as Plato, Rousseau, Freire, Apple, and the New London Group have understood education as a practice that "makes" humans. Positing education as a practice of humanization has long been understood to be the highest, most lofty good. By drawing on feminism, critical race studies, and postcolonial studies, the author of…

14 CFR 25.109 - Accelerate-stop distance.

Code of Federal Regulations, 2011 CFR

2011-01-01

....109 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... highest speed reached during the rejected takeoff, assuming the critical engine fails at VEF and the pilot... a full stop on a dry runway from the speed reached as prescribed in paragraph (a)(1)(ii) of this...

14 CFR 25.109 - Accelerate-stop distance.

Code of Federal Regulations, 2010 CFR

2010-01-01

....109 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... highest speed reached during the rejected takeoff, assuming the critical engine fails at VEF and the pilot... a full stop on a dry runway from the speed reached as prescribed in paragraph (a)(1)(ii) of this...

14 CFR 25.109 - Accelerate-stop distance.

Code of Federal Regulations, 2014 CFR

2014-01-01

....109 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... highest speed reached during the rejected takeoff, assuming the critical engine fails at VEF and the pilot... a full stop on a dry runway from the speed reached as prescribed in paragraph (a)(1)(ii) of this...

14 CFR 25.109 - Accelerate-stop distance.

Code of Federal Regulations, 2012 CFR

2012-01-01

....109 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... highest speed reached during the rejected takeoff, assuming the critical engine fails at VEF and the pilot... a full stop on a dry runway from the speed reached as prescribed in paragraph (a)(1)(ii) of this...

14 CFR 25.109 - Accelerate-stop distance.

Code of Federal Regulations, 2013 CFR

2013-01-01

....109 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... highest speed reached during the rejected takeoff, assuming the critical engine fails at VEF and the pilot... a full stop on a dry runway from the speed reached as prescribed in paragraph (a)(1)(ii) of this...

The association between alcohol, marijuana use, and new and emerging tobacco products in a young adult population.

PubMed

Cohn, Amy; Villanti, Andrea; Richardson, Amanda; Rath, Jessica M; Williams, Valerie; Stanton, Cassandra; Mermelstein, Robin

2015-09-01

Young adults have the highest rates of alcohol, tobacco, and other drug use relative to any other age group. Few studies have examined the co-occurrence of substance use with new and emerging tobacco products in this vulnerable group, or the underlying personality factors that may explain these associations. To address this gap, this study examined the association of current alcohol and marijuana use with the use of cigarettes and emerging tobacco products in a nationally representative sample of young adults. Data were drawn from 18 to 24year olds in Wave 4 (January 2013; n=1609) of the Legacy Young Adult Cohort, a nationally-representative sample of men and women. Never, ever (lifetime), and past 30-day use of little cigars/cigarillos (LCCs), hookah, e-cigarettes, and cigarettes were assessed separately in current (everyday or some days) alcohol and marijuana users. Using weighted estimates, multivariable multinomial logistic regression models showed that current alcohol and marijuana use were associated with lifetime and past 30-day use of cigarettes, LCCs, e-cigarettes, and hookah, with different magnitudes of association found across each product. Post-hoc exploratory analyses showed that sensation-seeking traits moderated the relationship of alcohol (but not marijuana) use to current use of select tobacco products. Marijuana and alcohol use may enhance risk for emerging tobacco products use in young adulthood. Prevention and intervention programs may need to target poly-use of alcohol, marijuana, and tobacco rather than focusing on a single risk behavior during these critical years. Copyright © 2015 Elsevier Ltd. All rights reserved.

Correlations between critical current density, j(sub c), critical temperature, T(sub c),and structural quality of Y1B2Cu3O(7-x) thin superconducting films

NASA Technical Reports Server (NTRS)

Chrzanowski, J.; Xing, W. B.; Atlan, D.; Irwin, J. C.; Heinrich, B.; Cragg, R. A.; Zhou, H.; Angus, V.; Habib, F.; Fife, A. A.

1995-01-01

Correlations between critical current density (j(sub c)) critical temperature (T(sub c)) and the density of edge dislocations and nonuniform strain have been observed in YBCO thin films deposited by pulsed laser ablation on (001) LaAlO3 single crystals. Distinct maxima in j(sub c) as a function of the linewidths of the (00 l) Bragg reflections and as a function of the mosaic spread have been found in the epitaxial films. These maxima in j(sub c) indicate that the magnetic flux lines, in films of structural quality approachingthat of single crystals, are insufficiently pinned which results in a decreased critical current density. T(sub c) increased monotonically with improving crystalline quality and approached a value characteristic of a pure single crystal. A strong correlation between j(sub c) and the density of edge dislocations ND was found. At the maximum of the critical current density the density of edge dislocations was estimated to be N(sub D) approximately 1-2 x 10(exp 9)/sq cm.

The burden of surgical diseases on critical care services at a tertiary hospital in sub-Saharan Africa.

PubMed

Tomlinson, Jared; Haac, Bryce; Kadyaudzu, Clement; Samuel, Jonathan C; Campbell, Emilia L P; Lee, Clara N; Charles, Anthony G

2013-01-01

In many developing countries, including those of sub-Saharan Africa, care of the critically ill is poorly developed. We sought to elucidate the characteristics and outcomes of critically ill patients in order to better define the burden of disease and identify strategies for improving care. We conducted a cross sectional observation study of patients admitted to the intensive care unit at Kamuzu Central Hospital in 2010. Demographics, patient characteristics, clinical specialty and outcome data was collected for the 234 patients admitted during the study period. Older age and admission from trauma, general surgery or medical services were associated with increased mortality. The lowest mortality was among obstetrical and gynaecology patients. Use of the ventilator and transfusions were not associated with increased mortality. Patients with head injuries had the highest mortality rate. Rationing of critical care resources, using admitting diagnosis or scoring tools, can maximize access to critical care services in resource-limited settings. Furthermore, improvements of critical care services will be central to future efforts to reduce surgical morbidity and mortality and improving outcomes in all critically ill patients.

Pathway cross-talk network analysis identifies critical pathways in neonatal sepsis.

PubMed

Meng, Yu-Xiu; Liu, Quan-Hong; Chen, Deng-Hong; Meng, Ying

2017-06-01

Despite advances in neonatal care, sepsis remains a major cause of morbidity and mortality in neonates worldwide. Pathway cross-talk analysis might contribute to the inference of the driving forces in bacterial sepsis and facilitate a better understanding of underlying pathogenesis of neonatal sepsis. This study aimed to explore the critical pathways associated with the progression of neonatal sepsis by the pathway cross-talk analysis. By integrating neonatal transcriptome data with known pathway data and protein-protein interaction data, we systematically uncovered the disease pathway cross-talks and constructed a disease pathway cross-talk network for neonatal sepsis. Then, attract method was employed to explore the dysregulated pathways associated with neonatal sepsis. To determine the critical pathways in neonatal sepsis, rank product (RP) algorithm, centrality analysis and impact factor (IF) were introduced sequentially, which synthetically considered the differential expression of genes and pathways, pathways cross-talks and pathway parameters in the network. The dysregulated pathways with the highest IF values as well as RP<0.01 were defined as critical pathways in neonatal sepsis. By integrating three kinds of data, only 6919 common genes were included to perform the pathway cross-talk analysis. By statistic analysis, a total of 1249 significant pathway cross-talks were selected to construct the pathway cross-talk network. Moreover, 47 dys-regulated pathways were identified via attract method, 20 pathways were identified under RP<0.01, and the top 10 pathways with the highest IF were also screened from the pathway cross-talk network. Among them, we selected 8 common pathways, i.e. critical pathways. In this study, we systematically tracked 8 critical pathways involved in neonatal sepsis by integrating attract method and pathway cross-talk network. These pathways might be responsible for the host response in infection, and of great value for advancing diagnosis and therapy of neonatal sepsis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Intrinsic and extrinsic pinning in NdFeAs(O,F): vortex trapping and lock-in by the layered structure

NASA Astrophysics Data System (ADS)

Tarantini, C.; Iida, K.; Hänisch, J.; Kurth, F.; Jaroszynski, J.; Sumiya, N.; Chihara, M.; Hatano, T.; Ikuta, H.; Schmidt, S.; Seidel, P.; Holzapfel, B.; Larbalestier, D. C.

2016-10-01

Fe-based superconductors (FBS) present a large variety of compounds whose properties are affected to different extents by their crystal structures. Amongst them, the REFeAs(O,F) (RE1111, RE being a rare-earth element) is the family with the highest critical temperature Tc but also with a large anisotropy and Josephson vortices as demonstrated in the flux-flow regime in Sm1111 (Tc ∼ 55 K). Here we focus on the pinning properties of the lower-Tc Nd1111 in the flux-creep regime. We demonstrate that for H//c critical current density Jc at high temperatures is dominated by point-defect pinning centres, whereas at low temperatures surface pinning by planar defects parallel to the c-axis and vortex shearing prevail. When the field approaches the ab-planes, two different regimes are observed at low temperatures as a consequence of the transition between 3D Abrikosov and 2D Josephson vortices: one is determined by the formation of a vortex-staircase structure and one by lock-in of vortices parallel to the layers. This is the first study on FBS showing this behaviour in the full temperature, field, and angular range and demonstrating that, despite the lower Tc and anisotropy of Nd1111 with respect to Sm1111, this compound is substantially affected by intrinsic pinning generating a strong ab-peak in Jc.

The ties that bind: what's in a title?

PubMed

Neuhaus, Susan J

2018-03-01

Many Australian and New Zealand surgeons use the title 'Mister' rather than 'Doctor', a practice dating back to traditions established over 600 years ago. The Royal Australasian College of Surgeons is currently undergoing a period of critical self-reflection, embodied by its 'Respect' campaign. Active measures to embrace diversity and encourage women into surgery are underway. This paper reviews the historical basis to the use of gendered titles and their current use amongst fellows. De-identified demographic data from the college register of active fellows was searched by self-identified title, country or state, and gender. Data were further reviewed by surgical sub-specialty and year of fellowship. The college dataset suggests that there is significant variance in the preference for gendered titles, determined predominantly by geography rather than specialty. The highest use of gendered titles (by male and female surgeons) was in Victoria/Tasmania (58% male, 22% female) and New Zealand (81% male, 17% female). By contrast, only 2% of female surgeons in other states elected a gendered title (Miss/Mrs/Ms). Surgery is the only profession that continues to use gendered titles. As the College of Surgeons moves towards greater equity and diversity, consideration should be given to phasing out the use of gendered titles, which serve to divide rather than unite our profession. © 2017 Royal Australasian College of Surgeons.

Enhanced performance of a novel anodic PdAu/VGCNF catalyst for electro-oxidation in a glycerol fuel cell.

PubMed

Yahya, N; Kamarudin, S K; Karim, N A; Masdar, M S; Loh, K S

2017-11-25

This study presents a novel anodic PdAu/VGCNF catalyst for electro-oxidation in a glycerol fuel cell. The reaction conditions are critical issues affecting the glycerol electro-oxidation performance. This study presents the effects of catalyst loading, temperature, and electrolyte concentration. The glycerol oxidation performance of the PdAu/VGCNF catalyst on the anode side is tested via cyclic voltammetry with a 3 mm 2 active area. The morphology and physical properties of the catalyst are examined using X-ray diffraction (XRD), field emission scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy. Then, optimization is carried out using the response surface method with central composite experimental design. The current density is experimentally obtained as a response variable from a set of experimental laboratory tests. The catalyst loading, temperature, and NaOH concentration are taken as independent parameters, which were evaluated previously in the screening experiments. The highest current density of 158.34 mAcm -2 is obtained under the optimal conditions of 3.0 M NaOH concentration, 60 °C temperature and 12 wt.% catalyst loading. These results prove that PdAu-VGCNF is a potential anodic catalyst for glycerol fuel cells.

Many atolls may be uninhabitable within decades due to climate change

USGS Publications Warehouse

Storlazzi, Curt; Elias, Edwin P.L.; Berkowitz, Paul

2015-01-01

Observations show global sea level is rising due to climate change, with the highest rates in the tropical Pacific Ocean where many of the world’s low-lying atolls are located. Sea-level rise is particularly critical for low-lying carbonate reef-lined atoll islands; these islands have limited land and water available for human habitation, water and food sources, and ecosystems that are vulnerable to inundation from sea-level rise. Here we demonstrate that sea-level rise will result in larger waves and higher wave-driven water levels along atoll islands’ shorelines than at present. Numerical model results reveal waves will synergistically interact with sea-level rise, causing twice as much land forecast to be flooded for a given value of sea-level rise than currently predicted by current models that do not take wave-driven water levels into account. Atolls with islands close to the shallow reef crest are more likely to be subjected to greater wave-induced run-up and flooding due to sea-level rise than those with deeper reef crests farther from the islands’ shorelines. It appears that many atoll islands will be flooded annually, salinizing the limited freshwater resources and thus likely forcing inhabitants to abandon their islands in decades, not centuries, as previously thought.

High-Density Superconducting Cables for Advanced ACTPol

NASA Astrophysics Data System (ADS)

Pappas, C. G.; Austermann, J.; Beall, J. A.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Henderson, S. W.; Ho, S. P.; Koopman, B. J.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Niraula, P.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

2016-07-01

Advanced ACTPol (AdvACT) is an upcoming Atacama Cosmology Telescope (ACT) receiver upgrade, scheduled to deploy in 2016, that will allow measurement of the cosmic microwave background polarization and temperature to the highest precision yet with ACT. The AdvACT increase in sensitivity is partly provided by an increase in the number of transition-edge sensors (TESes) per array by up to a factor of two over the current ACTPol receiver detector arrays. The high-density AdvACT TES arrays require 70 \\upmu m pitch superconducting flexible cables (flex) to connect the detector wafer to the first-stage readout electronics. Here, we present the flex fabrication process and test results. For the flex wiring layer, we use a 400-nm-thick sputtered aluminum film. In the center of the cable, the wiring is supported by a polyimide substrate, which smoothly transitions to a bare (uncoated with polyimide) silicon substrate at the ends of the cable for a robust wedge wire-bonding interface. Tests on the first batch of flex made for the first AdvACT array show that the flex will meet the requirements for AdvACT, with a superconducting critical current above 1 mA at 500 mK, resilience to mechanical and cryogenic stress, and a room temperature yield of 97 %.

High-Density Superconducting Cables for Advanced ACTPol

NASA Technical Reports Server (NTRS)

Pappas, C. G.; Austermann, J.; Beall, J. A.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Henderson, S. W.; Ho, S. P.; Koopman, B. J.; Li, D.;

Excess current experiment on YBCO tape conductor with metal stabilized layer

NASA Astrophysics Data System (ADS)

Tasaki, Kenji; Yazawa, Takashi; Ono, Michitaka; Kuriyama, Toru

2006-06-01

Excess current experiments were performed using YBCO tape conductors with a metal stabilized layer on the superconducting layer. The purpose of this research is to obtain the stable criteria of energy dissipation when YBCO tape is forced to flow excess current higher than its critical current. This situation should be considered in power applications. In the experiments short-length samples were immersed in liquid nitrogen and several cycles of 50Hz sinusoidal current were supplied to the samples by an induction voltage regulator. The critical current of the samples was about 110 A. With pulse length as long as 60 ms, YBCO tapes were able to be energized up to twelve times as the critical current without electrical or mechanical deformation. Prior to the excess current experiments, temperature dependency of resistance of the sample was measured so that the temperature rise was estimated by the generated resistance. It is found that YBCO tapes with a copper stabilized layer can be transiently heated to over 400K without degradation.

English Learners: Reaching the Highest Level of English Literacy.

ERIC Educational Resources Information Center

Garcia, Gilbert C., Ed.

This collection of papers examines the critical literacy development of English learners, focusing on English reading instruction in an immersion setting, English language development, and cultural issues pertaining to English learners in and out of the classroom. The 16 papers include the following: (1) "Reading and the Bilingual Student: Fact…

The influence of winding direction of two-layer HTS DC cable on the critical current

NASA Astrophysics Data System (ADS)

Vyatkin, V. S.; Kashiwagi, K.; Ivanov, Y. V.; Otabe, E. S.; Yamaguchi, S.

2017-09-01

The design of twist pitch and direction of winding in multilayer HTS coaxial cable is important. For HTS AC transmitting cables, the main condition of twist pitch is the balance of inductances of each layer for providing the current balance between layers. In this work, the finite element method analysis for the coaxial cables with both same and opposite directions winding is used to calculate magnetic field distribution, and critical current of the cable is estimated. It was found that the critical current of the cable with same direction winding is about 10 percent higher than that in the case of the cable with the opposite direction winding.

Critical Education, Critical Pedagogies, Marxist Education in the United States

ERIC Educational Resources Information Center

Foley, Jean Ann; Morris, Doug; Gounari, Panayota; Agostinone-Wilson, Faith

2015-01-01

As critical pedagogy becomes more mainstream on the educational landscape in the United States, it is important to revisit the original tenets of critical pedagogy and explore their current manifestations. Since the beginning of "criticalism" from the theoretical/foundational work of the Frankfurt School of Critical Social Theory,…

Biodistribution and radiation dosimetry of the hypoxia marker 18F-HX4 in monkeys and humans determined by using whole-body PET/CT.

PubMed

Doss, Mohan; Zhang, James J; Bélanger, Marie-José; Stubbs, James B; Hostetler, Eric D; Alpaugh, Katherine; Kolb, Hartmuth C; Yu, Jian Q

2010-12-01

F-HX4 is a novel positron emission tomography (PET) tracer for imaging hypoxia. The purpose of this study was to determine the biodistribution and estimate the radiation dose of F-HX4 using whole-body PET/computed tomography (CT) scans in monkeys and humans. Successive whole-body PET/CT scans were done after the injection of F-HX4 in four healthy humans (422±142 MBq) and in three rhesus monkeys (189±3 MBq). Biodistribution was determined from PET images and organ doses were estimated using OLINDA/EXM software. The bladder, liver, and kidneys showed the highest percentage of the injected radioactivity for humans and monkeys. For humans, approximately 45% of the activity is eliminated by bladder voiding in 3.6 h, and for monkeys 60% is in the bladder content after 3 h. The critical organ is the urinary bladder wall with the highest absorbed radiation dose of 415±18 (monkeys) and 299±38 μGy/MBq (humans), in the 4.8-h bladder voiding interval model. The average value of effective dose for the adult male was estimated at 42±4.2 μSv/MBq from monkey data and 27±2 μSv/MBq from human data. Bladder, kidneys, and liver have the highest uptake of injected F-HX4 activity for both monkeys and humans. The urinary bladder wall receives the highest dose of F-HX4 and is the critical organ. Thus, patients should be encouraged to maintain adequate hydration and void frequently. The effective dose of F-HX4 is comparable with that of other F-based imaging agents.

Critical current studies of a HTS rectangular coil

NASA Astrophysics Data System (ADS)

Zhong, Z.; Chudy, M.; Ruiz, H. S.; Zhang, X.; Coombs, T.

2017-05-01

Nowadays, superconducting high field magnets are used in numerous applications due to their superior properties. High temperature superconductors (HTS) are usually used for production of circular pancake or racetrack coils. However different geometries of HTS coils might be required for some specific applications. In this study, the HTS coil wound on a rectangular frame was fully characterized in homogeneous DC background field. The study contains measurements of critical current angular dependencies. The critical current of the entire coil and two selected strands under different magnitudes and orientations of external magnetic fields are measured. The critical regions of the coil in different angular regimes are determined. This study brings better understanding of the in- field performance of HTS coils wound on frames with right-angles.

RAPID COMMUNICATION: Effect of strain, magnetic field and field angle on the critical current density of Y Ba2Cu3O7-δ coated conductors

NASA Astrophysics Data System (ADS)

van der Laan, D. C.; Ekin, J. W.; Douglas, J. F.; Clickner, C. C.; Stauffer, T. C.; Goodrich, L. F.

2010-07-01

A large, magnetic-field-dependent, reversible reduction in critical current density with axial strain in Y Ba2Cu3O7-δ coated conductors at 75.9 K has been measured. This effect may have important implications for the performance of Y Ba2Cu3O7-δ coated conductors in applications where the conductor experiences large stresses in the presence of a magnetic field. Previous studies have been performed only under tensile strain and could provide only a limited understanding of the in-field strain effect. We now have constructed a device for measuring the critical current density as a function of axial compressive and tensile strain and applied magnetic field as well as magnetic field angle, in order to determine the magnitude of this effect and to create a better understanding of its origin. The reversible reduction in critical current density with strain becomes larger with increasing magnetic field at all field angles. At 76 K the critical current density is reduced by about 30% at - 0.5% strain when a magnetic field of 5 T is applied parallel to the c-axis of the conductor or 8 T is applied in the ab-plane, compared to a reduction of only 13% in self-field. Differences in the strain response of the critical current density at various magnetic field angles indicate that the pinning mechanisms in Y Ba2Cu3O7-δ coated conductors are uniquely affected by strain. Contribution of NIST, not subject to US copyright.

Spatial characterization of the edge barrier in wide superconducting films

NASA Astrophysics Data System (ADS)

Sivakov, A. G.; Turutanov, O. G.; Kolinko, A. E.; Pokhila, A. S.

2018-03-01

The current-induced destruction of superconductivity is discussed in wide superconducting thin films, whose width is greater than the magnetic field penetration depth, in weak magnetic fields. Particular attention is paid to the role of the boundary potential barrier (the Bin-Livingston barrier) in critical state formation and detection of the edge responsible for this critical state with different mutual orientations of external perpendicular magnetic field and transport current. Critical and resistive states of the film were visualized using the space-resolving low-temperature laser scanning microscopy (LTLSM) method, which enables detection of critical current-determining areas on the film edges. Based on these observations, a simple technique was developed for investigation of the critical state separately at each film edge, and for the estimation of residual magnetic fields in cryostats. The proposed method only requires recording of the current-voltage characteristics of the film in a weak magnetic field, thus circumventing the need for complex LTLSM techniques. Information thus obtained is particularly important for interpretation of studies of superconducting film single-photon light emission detectors.

Enhanced total neurite outgrowth and secondary branching in dorsal root ganglion neurons elicited by low intensity pulsed ultrasound.

PubMed

Ventre, Daniel; Puzan, Marissa; Ashbolt, Emily; Koppes, Abigail

2018-04-17

Despite the prevalence of peripheral nerve injuries (PNI), challenges remain in restoring full functionality to those afflicted. For recovery to occur, axons must extend across the injury site to connect with distal targets, where injury gap size is a critical factor in the probability of restoration of function. Current clinical therapies often achieve limited neural regeneration, motivating the development of new therapeutic interventions such as biophysical stimulation. To investigate the potential for low intensity, pulsed ultrasonic simulation (LIPUS) to impact peripheral nerve regeneration, primary neonatal rat dorsal root ganglion neurons were examined in vitro in response to ultrasound (US). Dissociated neurons were stimulated with varied acoustic power (low, medium, high) and their morphometrics, including total outgrowth, branching, and length, were analyzed acutely after 18 h of growth. Results show US increases total neurite outgrowth by 2.83-fold compared to unstimulated controls at the highest power. Neurite branching at medium and high-power US increased approximately 2-fold compared to controls, while low stimulation exhibited more muted trends. Neurite branching is also impacted by US, with medium and high power eliciting the highest branching, of approximately 2-fold compared to low power and unstimulated controls. These results demonstrate that US stimulation of DRG neurons in vitro impacts neurite morphology and enhances total extension, indicating the potential for advancing and understanding driving mechanisms of ultrasonic therapies for peripheral nerve regeneration.

An economic comparison of different fermentation configurations to convert corn stover to ethanol using Z. mobilis and Saccharomyces.

PubMed

Dutta, Abhijit; Dowe, Nancy; Ibsen, Kelly N; Schell, Daniel J; Aden, Andy

2010-01-01

Numerous routes are being explored to lower the cost of cellulosic ethanol production and enable large-scale production. One critical area is the development of robust cofermentative organisms to convert the multiple, mixed sugars found in biomass feedstocks to ethanol at high yields and titers without the need for processing to remove inhibitors. Until such microorganisms are commercialized, the challenge is to design processes that exploit the current microorganisms' strengths. This study explored various process configurations tailored to take advantage of the specific capabilities of three microorganisms, Z. mobilis 8b, S. cerevisiae, and S. pastorianus. A technoeconomic study, based on bench-scale experimental data generated by integrated process testing, was completed to understand the resulting costs of the different process configurations. The configurations included whole slurry fermentation with a coculture, and separate cellulose simultaneous saccharification and fermentation (SSF) and xylose fermentations with none, some or all of the water to the SSF replaced with the fermented liquor from the xylose fermentation. The difference between the highest and lowest ethanol cost for the different experimental process configurations studied was $0.27 per gallon ethanol. Separate fermentation of solid and liquor streams with recycle of fermented liquor to dilute the solids gave the lowest ethanol cost, primarily because this option achieved the highest concentrations of ethanol after fermentation. Further studies, using methods similar to ones employed here, can help understand and improve the performance and hence the economics of integrated processes involving enzymes and fermentative microorganisms.

Perpendicular magnetic anisotropy in CoXPd100-X alloys for magnetic tunnel junctions

NASA Astrophysics Data System (ADS)

Clark, B. D.; Natarajarathinam, A.; Tadisina, Z. R.; Chen, P. J.; Shull, R. D.; Gupta, S.

2017-08-01

CoFeB/MgO-based perpendicular magnetic tunnel junctions (p-MTJ's) with high anisotropy and low damping are critical for spin-torque transfer random access memory (STT-RAM). Most schemes of making the pinned CoFeB fully perpendicular require ferrimagnets with high damping constants, a high temperature-grown L10 alloy, or an overly complex multilayered synthetic antiferromagnet (SyAF). We report a compositional study of perpendicular CoxPd alloy-pinned Co20Fe60B20/MgO based MTJ stacks, grown at moderate temperatures in a planetary deposition system. The perpendicular anisotropy of the CoxPd alloy films can be tuned based on the layer thickness and composition. The films were characterized by alternating gradient magnetometry (AGM), energy-dispersive X-rays (EDX), and X-ray diffraction (XRD). Current-in-plane tunneling (CIPT) measurements have also been performed on the compositionally varied CoxPd MTJ stacks. The CoxPd alloy becomes fully perpendicular at approximately x = 30% (atomic fraction) Co. Full-film MTJ stacks of Si/SiO2/MgO (13)/CoXPd100-x (50)/Ta (0.3)/CoFeB (1)/MgO (1.6)/CoFeB (1)/Ta (5)/Ru (10), with the numbers enclosed in parentheses being the layer thicknesses in nm, were sputtered onto thermally oxidized silicon substrates and in-situ lamp annealed at 400 °C for 5 min. CIPT measurements indicate that the highest TMR is observed for the CoPd composition with the highest perpendicular magnetic anisotropy.

Effect of nano BiPb-2212 phase addition on BiPb-2223 phase properties

NASA Astrophysics Data System (ADS)

Mohammed, N. H.; Abou-Aly, A. I.; Barakat, M. Me.; Hassan, M. S.

2018-06-01

BiPb-2212 phase in nanoscale was added to BiPb-2223 phase with a general stoichiometry of (Bi1.7Pb0.4Sr2.1Ca1.1Cu2.1O8+δ)x/Bi1.8Pb0.4Sr2.0Ca2.0Cu3.2O10+δ, 0.0 ≤ x  ≤ 2.5 wt.%. All samples were prepared by the standard solid-state reaction method. The prepared nano BiPb-2212 phase was characterized by X-ray powder diffraction (XRD) and transmission electron microscope (TEM). The prepared samples were characterized by XRD and the scanning electron microscope (SEM). XRD analysis indicated that the sample with x = 1.5 wt.% has the highest relative volume fraction for BiPb-2223 phase. Samples were examined by electrical resistivity and I-V measurements. There is no significant change in the superconducting transition temperature Tc for all samples. The highest critical current density Jc was recorded for the sample with x = 1.5 wt.%. The normalized excess conductivity (Δσ/σroom) was calculated according to Aslamazov-Larkin (AL) model. Four different fluctuating regions were recorded as the temperature decreased. The coherence length along the c-axis at 0 K ξc(0), interlayer coupling strength s, Fermi velocity vF of the carriers and Fermi energy EF were calculated for both samples with x = 0.0 wt.% and 1.5 wt.%.

Pulmonary deposition modeling with airborne fiber exposure data: a study of workers manufacturing refractory ceramic fibers.

PubMed

Lentz, Thomas J; Rice, Carol H; Succop, Paul A; Lockey, James E; Dement, John M; LeMasters, Grace K

2003-04-01

Increasing production of refractory ceramic fiber (RCF), a synthetic vitreous material with industrial applications (e.g., kiln insulation), has created interest in potential respiratory effects of exposure to airborne fibers during manufacturing. An ongoing study of RCF manufacturing workers in the United States has indicated an association between cumulative fiber exposure and pleural plaques. Fiber sizing data, obtained from electron microscopy analyses of 118 air samples collected in three independent studies over a 20-year period (1976-1995), were used with a computer deposition model to estimate pulmonary dose of fibers of specified dimensions for 652 former and current RCF production workers. Separate dose correction factors reflecting differences in fiber dimensions in six uniform job title groups were used with data on airborne fiber concentration and employment duration to calculate cumulative dose estimates for each worker. From review of the literature, critical dimensions (diameter <0.4 microm, length <10 microm) were defined for fibers that may translocate to the parietal pleura. Each of three continuous exposure/dose metrics analyzed in separate logistic regression models was significantly related to plaques, even after adjusting for possible past asbestos exposure: cumulative fiber exposure, chi(2) = 15.2 (p < 0.01); cumulative pulmonary dose (all fibers), chi(2) = 14.6 (p < 0.01); cumulative pulmonary dose (critical dimension fibers), chi(2) = 12.4 (p < 0.01). Odds ratios (ORs) were calculated for levels of each metric. Increasing ORs were statistically significant for the two highest dose levels of critical dimension fibers (level three, OR = 11, 95%CI = [1.4, 98]; level four, OR = 25, 95%CI = [3.2, 190]). Similar associations existed for all metrics after adjustment for possible asbestos exposure. It was concluded that development of pleural plaques follows exposure- and dose-response patterns, and that airborne fibers in RCF manufacturing facilities include those with critical dimensions associated with pleural plaque formation. Analysis of additional air samples may improve estimates of the dose-response relationship.

Lung Cancer Screening May Benefit Those at Highest Risk

Cancer.gov

People at the highest risk for lung cancer, based on a risk model, may be more likely to benefit from screening with low-dose CT, a new analysis suggests. The study authors believe the findings may better define who should undergo lung cancer screening, as this Cancer Currents blog post explains.

Efforts Aimed To Reduce Attrition in Antimalarial Drug Discovery: A Systematic Evaluation of the Current Antimalarial Targets Portfolio.

PubMed

Chaparro, María Jesús; Calderón, Félix; Castañeda, Pablo; Fernández-Alvaro, Elena; Gabarró, Raquel; Gamo, Francisco Javier; Gómez-Lorenzo, María G; Martín, Julio; Fernández, Esther

2018-04-13

Malaria remains a major global health problem. In 2015 alone, more than 200 million cases of malaria were reported, and more than 400,000 deaths occurred. Since 2010, emerging resistance to current front-line ACTs (artemisinin combination therapies) has been detected in endemic countries. Therefore, there is an urgency for new therapies based on novel modes of action, able to relieve symptoms as fast as the artemisinins and/or block malaria transmission. During the past few years, the antimalarial community has focused their efforts on phenotypic screening as a pragmatic approach to identify new hits. Optimization efforts on several chemical series have been successful, and clinical candidates have been identified. In addition, recent advances in genetics and proteomics have led to the target deconvolution of phenotypic clinical candidates. New mechanisms of action will also be critical to overcome resistance and reduce attrition. Therefore, a complementary strategy focused on identifying well-validated targets to start hit identification programs is essential to reinforce the clinical pipeline. Leveraging published data, we have assessed the status quo of the current antimalarial target portfolio with a focus on the blood stage clinical disease. From an extensive list of reported Plasmodium targets, we have defined triage criteria. These criteria consider genetic, pharmacological, and chemical validation, as well as tractability/doability, and safety implications. These criteria have provided a quantitative score that has led us to prioritize those targets with the highest probability to deliver successful and differentiated new drugs.

Superconducting current injection transistor with very high critical-current-density edge-junctions

NASA Astrophysics Data System (ADS)

van Zeghbroeck, B. J.

1985-03-01

A Superconducting Current Injection Transistor (Super-CIT) was fabricated with very high critical current-density edge-junctions. The junctions have a niobium base electrode and a lead-alloy counter electrode. The length of the junctions is 30 microns and the critical-current density is 190KA/sq cm. The Super-CIT has a current gain of 2, a large signal transresistance of 100 mV/A, and the turn-on delay, inferred from the junction resonance, is 7ps. The power dissipation is 3.5 microwatts and the power-delay product is 24.5aJ. Gap reduction due to heating was observed, limiting the maximum power dissipation per unit length to 1.1 microwatt/micron. Compared to lead-alloy Super-CITs, the device is five times smaller, three times faster, and has a three times larger output voltage. The damping resistor and the contact junction could also be eliminated.

Buckling analysis of carbon nanotube bundles under axial compressive, bending and torsional loadings via a structural mechanics model

NASA Astrophysics Data System (ADS)

Lashkari Zadeh, Ali; Shariati, Mahmoud; Torabi, Hamid

2012-11-01

A structural mechanics model is employed for the investigation of the buckling behavior of carbon nanotube bundles of three single-walled carbon nanotubes (SWCNTs) under axial compressive, bending and torsional loadings. The effects of van der Waals (vdW) forces are further modeled using a nonlinear spring element.The effects of different types of boundary conditions are studied for nanotubes with various aspect ratios. The results reveal that bundles comprising longer SWCNTs exhibit lower critical buckling load. Moreover, for the fixed-free boundary condition the rate of critical buckling load reduction is highest, while the lowest critical buckling load occurs. Simulations show good agreement between our model and molecular dynamics results.

Advances in superconductivity and Co3O4 nanoparticles as flux pinning center in (Bi, Pb)-2223/Ag superconductor tapes

NASA Astrophysics Data System (ADS)

Abd-Shukor, R.; Jannah, A. N.

2017-09-01

Many new superconducting materials have been discovered in recent years. This includes hydrogen sulfide which superconducts at 203 K under high pressure and Fe-As based materials. To this date the copper oxide-based materials remain as the highest transition temperature superconductor under normal pressure. In this paper we discuss the use of nano-sized particle as pinning center in the Ag-sheathed high temperature superconductor tapes to enhance the transport properties. When the size d of the pinning center is between the coherence length ξ and the penetration depth λ (ξ < d < λ), a stronger interaction between the pinning center and flux lines leading to higher transport critical current density, Jc can be expected. The effect of nanoparticle with size between the coherence length and the penetration depth i.e. ξ < d < λ, Co3O4 on superconductor tapes is discussed in this paper. Three types of Bi(Pb)-Sr-Ca-Cu-O starting materials namely from co-precipitation method without Co3O4 and with 30 nm and 50 nm Co3O4 addition have been prepared. The composition of the 30 nm and 50 nm Co3O4 added samples is (Bi1.6Pb0.4)Sr2Ca2Cu3O10-(Co3O4)0.02 and (Bi1.6Pb0.4)Sr2Ca2Cu3O10-(Co3O4)0.01, respectively. The tapes (˜2-3 cm long) were heated at 845°C for 100 and 150 h. All nanoparticles added tapes showed higher Jc compared to the non-added tapes. By comparing the current results with our previously reported results, the tapes with 30 nm Co3O4 sintered for 50 h showed the highest Jc at all temperatures. This work also showed that smaller magnetic nanoparticles enhanced Jc better than larger particles, A longer sintering time (> 50 h) degraded Jc.

Analysis of the characteristics and management of critical values in a newborn tertiary center in China.

PubMed

Wang, Zheng-Li; Du, Li-Zhong; Chen, Yi-Yu; Li, Lu-Quan; Lu, Qi; Liu, Ying; Cao, Lu-Ying; He, Yu; Yu, Jia-Lin

2017-02-01

Critical value reporting has been widely adopted by hospitals throughout the world, but there were few reports about neonatal critical values. This study aimed to analyze characteristics of the neonatal critical values considered at our center and to provide information on improving neonatal intensive care. A retrospective study of critical values at a newborn tertiary center in China was conducted to assess neonatal critical values according to test, distribution, reporting time, patient outcome and the impact to the therapy. In total, 926 critical values were recorded. Overall, 66.52% (616/926) of the items were reported within 24 hours of admission, 50.28% (465/926) during duty times and 54.75% (507/926) in the neonatal intensive care unit (NICU). The routine coagulation test was the most frequent source of critical values. Electrocardiography, blood gas analysis and therapeutic drug monitoring of drug levels were associated with the highest rates of treatment intervention (100%); routine coagulation tests were the lowest (23.14%). Sample quality was the main cause of false-positive critical values. The incidence of neonatal critical values peaked during the first 24 hours post-admission and during duty periods. Each newborn center needs to enact rapid treatment guidelines to address common critical values in order to facilitate clinical interventions. Periodically reviewing critical values could help to optimize clinical practices.

Inclusion of Highest Glasgow Coma Scale Motor Component Score in Mortality Risk Adjustment for Benchmarking of Trauma Center Performance.

PubMed

Gomez, David; Byrne, James P; Alali, Aziz S; Xiong, Wei; Hoeft, Chris; Neal, Melanie; Subacius, Harris; Nathens, Avery B

2017-12-01

The Glasgow Coma Scale (GCS) is the most widely used measure of traumatic brain injury (TBI) severity. Currently, the arrival GCS motor component (mGCS) score is used in risk-adjustment models for external benchmarking of mortality. However, there is evidence that the highest mGCS score in the first 24 hours after injury might be a better predictor of death. Our objective was to evaluate the impact of including the highest mGCS score on the performance of risk-adjustment models and subsequent external benchmarking results. Data were derived from the Trauma Quality Improvement Program analytic dataset (January 2014 through March 2015) and were limited to the severe TBI cohort (16 years or older, isolated head injury, GCS ≤8). Risk-adjustment models were created that varied in the mGCS covariates only (initial score, highest score, or both initial and highest mGCS scores). Model performance and fit, as well as external benchmarking results, were compared. There were 6,553 patients with severe TBI across 231 trauma centers included. Initial and highest mGCS scores were different in 47% of patients (n = 3,097). Model performance and fit improved when both initial and highest mGCS scores were included, as evidenced by improved C-statistic, Akaike Information Criterion, and adjusted R-squared values. Three-quarters of centers changed their adjusted odds ratio decile, 2.6% of centers changed outlier status, and 45% of centers exhibited a ≥0.5-SD change in the odds ratio of death after including highest mGCS score in the model. This study supports the concept that additional clinical information has the potential to not only improve the performance of current risk-adjustment models, but can also have a meaningful impact on external benchmarking strategies. Highest mGCS score is a good potential candidate for inclusion in additional models. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Use of EEG in critically ill children and neonates in the United States of America.

PubMed

Gaínza-Lein, Marina; Sánchez Fernández, Iván; Loddenkemper, Tobias

2017-06-01

The objective of the study was to estimate the proportion of patients who receive an electroencephalogram (EEG) among five common indications for EEG monitoring in the intensive care unit: traumatic brain injury (TBI), extracorporeal membrane oxygenation (ECMO), cardiac arrest, cardiac surgery and hypoxic-ischemic encephalopathy (HIE). We performed a retrospective cross-sectional descriptive study utilizing the Kids' Inpatient Database (KID) for the years 2010-2012. The KID is the largest pediatric inpatient database in the USA and it is based on discharge reports created by hospitals for billing purposes. We evaluated the use of electroencephalogram (EEG) or video-electroencephalogram in critically ill children who were mechanically ventilated. The KID database had a population of approximately 6,000,000 pediatric admissions. Among 22,127 admissions of critically ill children who had mechanical ventilation, 1504 (6.8%) admissions had ECMO, 9201 (41.6%) TBI, 4068 (18.4%) HIE, 2774 (12.5%) cardiac arrest, and 4580 (20.7%) cardiac surgery. All five conditions had a higher proportion of males, with the highest (69.8%) in the TBI group. The mortality rates ranged from 7.02 to 39.9% (lowest in cardiac surgery and highest in ECMO). The estimated use of EEG was 1.6% in cardiac surgery, 4.1% in TBI, 7.2% in ECMO, 8.2% in cardiac arrest, and 12.1% in HIE, with an overall use of 5.8%. Among common indications for EEG monitoring in critically ill children and neonates, the estimated proportion of patients actually having an EEG is low.

Critical levels and loads and the regulation of industrial emissions in northwest British Columbia, Canada

NASA Astrophysics Data System (ADS)

Williston, P.; Aherne, J.; Watmough, S.; Marmorek, D.; Hall, A.; de la Cueva Bueno, P.; Murray, C.; Henolson, A.; Laurence, J. A.

2016-12-01

Northwest British Columbia, Canada, a sparsely populated and largely pristine region, is targeted for rapid industrial growth owing to the modernization of an aluminum smelter and multiple proposed liquefied natural gas (LNG) facilities. Consequently, air quality in this region is expected to undergo considerable changes within the next decade. In concert, the increase in LNG capacity driven by gas production from shale resources across North America has prompted environmental concerns and highlighted the need for science-based management decisions regarding the permitting of air emissions. In this study, an effects-based approach widely-used to support transboundary emissions policy negotiations was used to assess industrial air emissions in the Kitimat and Prince Rupert airsheds under permitted and future potential industrial emissions. Critical levels for vegetation of SO2 and NO2 and critical loads of acidity and nutrient nitrogen for terrestrial and aquatic ecosystems were estimated for both regions and compared with modelled concentration and deposition estimates to identify the potential extent and magnitude of ecosystem impacts. The critical level for SO2 was predicted to be exceeded in an area ranging from 81 to 251 km2 in the Kitimat airshed owing to emissions from an existing smelter, compared with <1 km2 in Prince Rupert under the lowest to highest emissions scenarios. In contrast, the NO2 critical level was not exceeded in Kitimat, and ranged from 4.5 to 6 km2 in Prince Rupert owing to proposed LNG related emissions. Predicted areal exceedance of the critical load of acidity for soil ranged from 1 to 28 km2 in Kitimat and 4-10 km2 in Prince Rupert, while the areal exceedance of empirical critical load for nutrient N was predicted to be greater in the Prince Rupert airshed (20-94 km2) than in the Kitimat airshed (1-31 km2). The number of lakes that exceeded the critical load of acidity did not vary greatly across emissions scenarios in the Kitimat (21-23 out of 80 sampled lakes) and Prince Rupert (0 out of 35 sampled lakes) airsheds. While critical loads have been widely used to underpin international emissions reductions of transboundary pollutants, it is clear that they can also play an important role in managing regional air emissions. In the current study, exceedance of critical levels and loads suggests that industrial emissions from the nascent LNG export sector may require careful regulation to avoid environmental impacts. Emissions management from LNG export facilities in other regions should consider critical levels and loads analyses to ensure industrial development is synergistic with ecosystem protection. While recognizing uncertainties in dispersion modelling, critical load estimates, and subsequent effects, the critical levels and loads approach is being used to inform regulatory decisions in British Columbia to prevent impacts that have been well documented in other regions.

Assessing Students' Critical Thinking Performance: Urging for Measurements Using Multi-Response Format

ERIC Educational Resources Information Center

Ku, Kelly Y. L.

2009-01-01

The current paper discusses ambiguities in critical thinking assessment. The paper first reviews the components of critical thinking. It then discusses the features and issues of commonly used critical thinking tests and to what extend they are made compatible to the conceptualization of critical thinking. The paper argues that critical thinking…

On-line and real-time diagnosis method for proton membrane fuel cell (PEMFC) stack by the superposition principle

NASA Astrophysics Data System (ADS)

Lee, Young-Hyun; Kim, Jonghyeon; Yoo, Seungyeol

2016-09-01

The critical cell voltage drop in a stack can be followed by stack defect. A method of detecting defective cell is the cell voltage monitoring. The other methods are based on the nonlinear frequency response. In this paper, the superposition principle for the diagnosis of PEMFC stack is introduced. If critical cell voltage drops exist, the stack behaves as a nonlinear system. This nonlinearity can explicitly appear in the ohmic overpotential region of a voltage-current curve. To detect the critical cell voltage drop, a stack is excited by two input direct test-currents which have smaller amplitude than an operating stack current and have an equal distance value from the operating current. If the difference between one voltage excited by a test current and the voltage excited by a load current is not equal to the difference between the other voltage response and the voltage excited by the load current, the stack system acts as a nonlinear system. This means that there is a critical cell voltage drop. The deviation from the value zero of the difference reflects the grade of the system nonlinearity. A simulation model for the stack diagnosis is developed based on the SPP, and experimentally validated.

Questionnaires on Family Satisfaction in the Adult ICU: A Systematic Review Including Psychometric Properties.

PubMed

van den Broek, Janneke M; Brunsveld-Reinders, Anja H; Zedlitz, Aglaia M E E; Girbes, Armand R J; de Jonge, Evert; Arbous, M Sesmu

2015-08-01

To perform a systematic review of the literature to determine which questionnaires are currently available to measure family satisfaction with care on the ICU and to provide an overview of their quality by evaluating their psychometric properties. We searched PubMed, Embase, The Cochrane Library, Web of Science, PsycINFO, and CINAHL from inception to October 30, 2013. Experimental and observational research articles reporting on questionnaires on family satisfaction and/or needs in the ICU were included. Two reviewers determined eligibility. Design, application mode, language, and the number of studies of the tools were registered. With this information, the tools were globally categorized according to validity and reliability: level I (well-established quality), II (approaching well-established quality), III (promising quality), or IV (unconfirmed quality). The quality of the highest level (I) tools was assessed by further examination of the psychometric properties and sample size of the studies. The search detected 3,655 references, from which 135 articles were included. We found 27 different tools that assessed overall or circumscribed aspects of family satisfaction with ICU care. Only four questionnaires were categorized as level I: the Critical Care Family Needs Inventory, the Society of Critical Care Medicine Family Needs Assessment, the Critical Care Family Satisfaction Survey, and the Family Satisfaction in the Intensive Care Unit. Studies on these questionnaires were of good sample size (n ≥ 100) and showed adequate data on face/content validity and internal consistency. Studies on the Critical Care Family Needs Inventory, the Family Satisfaction in the Intensive Care Unit also contained sufficient data on inter-rater/test-retest reliability, responsiveness, and feasibility. In general, data on measures of central tendency and sensitivity to change were scarce. Of all the questionnaires found, the Critical Care Family Needs Inventory and the Family Satisfaction in the Intensive Care Unit were the most reliable and valid in relation to their psychometric properties. However, a universal "best questionnaire" is indefinable because it depends on the specific goal, context, and population used in the inquiry.

Criticality and turbulence in a resistive magnetohydrodynamic current sheet

NASA Astrophysics Data System (ADS)

Klimas, Alexander J.; Uritsky, Vadim M.

2017-02-01

Scaling properties of a two-dimensional (2d) plasma physical current-sheet simulation model involving a full set of magnetohydrodynamic (MHD) equations with current-dependent resistivity are investigated. The current sheet supports a spatial magnetic field reversal that is forced through loading of magnetic flux containing plasma at boundaries of the simulation domain. A balance is reached between loading and annihilation of the magnetic flux through reconnection at the current sheet; the transport of magnetic flux from boundaries to current sheet is realized in the form of spatiotemporal avalanches exhibiting power-law statistics of lifetimes and sizes. We identify this dynamics as self-organized criticality (SOC) by verifying an extended set of scaling laws related to both global and local properties of the current sheet (critical susceptibility, finite-size scaling of probability distributions, geometric exponents). The critical exponents obtained from this analysis suggest that the model operates in a slowly driven SOC state similar to the mean-field state of the directed stochastic sandpile model. We also investigate multiscale correlations in the velocity field and find them numerically indistinguishable from certain intermittent turbulence (IT) theories. The results provide clues on physical conditions for SOC behavior in a broad class of plasma systems with propagating instabilities, and suggest that SOC and IT may coexist in driven current sheets which occur ubiquitously in astrophysical and space plasmas.

Criticality and turbulence in a resistive magnetohydrodynamic current sheet.

PubMed

Klimas, Alexander J; Uritsky, Vadim M

2017-02-01

Scaling properties of a two-dimensional (2d) plasma physical current-sheet simulation model involving a full set of magnetohydrodynamic (MHD) equations with current-dependent resistivity are investigated. The current sheet supports a spatial magnetic field reversal that is forced through loading of magnetic flux containing plasma at boundaries of the simulation domain. A balance is reached between loading and annihilation of the magnetic flux through reconnection at the current sheet; the transport of magnetic flux from boundaries to current sheet is realized in the form of spatiotemporal avalanches exhibiting power-law statistics of lifetimes and sizes. We identify this dynamics as self-organized criticality (SOC) by verifying an extended set of scaling laws related to both global and local properties of the current sheet (critical susceptibility, finite-size scaling of probability distributions, geometric exponents). The critical exponents obtained from this analysis suggest that the model operates in a slowly driven SOC state similar to the mean-field state of the directed stochastic sandpile model. We also investigate multiscale correlations in the velocity field and find them numerically indistinguishable from certain intermittent turbulence (IT) theories. The results provide clues on physical conditions for SOC behavior in a broad class of plasma systems with propagating instabilities, and suggest that SOC and IT may coexist in driven current sheets which occur ubiquitously in astrophysical and space plasmas.

Mapping the current–current correlation function near a quantum critical point

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

Prodan, Emil, E-mail: prodan@yu.edu; Bellissard, Jean

2016-05-15

The current–current correlation function is a useful concept in the theory of electron transport in homogeneous solids. The finite-temperature conductivity tensor as well as Anderson’s localization length can be computed entirely from this correlation function. Based on the critical behavior of these two physical quantities near the plateau–insulator or plateau–plateau transitions in the integer quantum Hall effect, we derive an asymptotic formula for the current–current correlation function, which enables us to make several theoretical predictions about its generic behavior. For the disordered Hofstadter model, we employ numerical simulations to map the current–current correlation function, obtain its asymptotic form near amore » critical point and confirm the theoretical predictions.« less

Filling the Void: A Multi-Component, Culturally Adapted Smoking Cessation Program Integrating Western and Non-Western Therapies

ERIC Educational Resources Information Center

Beckham, Sheila; Washburn, Anuenue; Ka'aha'aina, Darlene; Bradley, Stephen

2007-01-01

Background: Smoking is especially prevalent among Native Hawaiians. The 2002 Behavioral Risk Factor Surveillance System revealed that 33.8% of Hawaiians were current smokers. Native Hawaiians have the highest age-adjusted lung cancer incidence and mortality rates and the highest prevalence of asthma among all ethnicities. Purpose: This study…

A "Networked-Hutong Siwei of Critiques" for Critical Teacher Education

ERIC Educational Resources Information Center

Qi, Jing

2014-01-01

This paper offers a conceptual basis for refashioning the formulation of critical teacher education. It argues that current critical teacher education is uncritically constructed upon key theoretical departures from critical theories. Drawing on Boltanski's critique of critical theories, the paper examines the ways these theoretical departures…

Feminist Literary Criticism; Explorations in Theory.

ERIC Educational Resources Information Center

Donovan, Josephine, Ed.

A collection of five essays (plus preface and afterword) by noted feminist critics, this book provides an overview of the existing body of feminist literary criticism in order to promote an understanding of the issues feminist critics are currently discussing among themselves and with other critics. A theoretical framework for understanding this…

Backers of "21st-Century Skills" Take Flak

ERIC Educational Resources Information Center

Sawchuk, Stephen

2009-01-01

The phrase "21st-century skills" is everywhere in education policy discussions these days, from faculty lounges to the highest echelons of the U.S. education system. Broadly speaking, it refers to a push for schools to teach critical-thinking, analytical, and technology skills, in addition to the "soft skills" of creativity, collaboration, and…

The Areal Extent of Brown Shrimp Habitat Suitability in Mobile Bay, Alabama USA: Targeting Vegetated Habitat Restoration

EPA Science Inventory

The availability of wetlands and shallow water habitats significantly influences Gulf of Mexico (GOM) penaeid shrimp fishery productivity. However, the GOM region has the highest rate of wetland loss in the U.S. Protection and management of these vital GOM habitats are critical t...

Continuing Education Needs of the Office Oncology Nurse.

ERIC Educational Resources Information Center

Rogers, Miriam P.

1999-01-01

A study determined the learning needs of office oncology nurses (n=290)as a critical first step in planning education programs. Participants ranked cancer-care topics similarly, regardless of age, background, or experience. The highest-ranked needs were clustered in the areas of cancer nursing practice, major cancers, and cancer treatment.…

47 CFR Appendix B to Part 64 - Priority Access Service (PAS) for National Security and Emergency Preparedness (NSEP)

Code of Federal Regulations, 2010 CFR

2010-10-01

... leadership; (iii) Disaster shelter coordination and management; and (iv) Critical Disaster Field Office... telecommunications management and response functions during emergency/disaster situations. 3. Initiate PAS requests... priorities, priority one being the highest. The five priority levels are: 1. Executive Leadership and Policy...

Developing Middle Grades Students' MP3

ERIC Educational Resources Information Center

Tassell, Janet; Stobaugh, Rebecca; Sheffield, Linda

2011-01-01

Middle grades are a critical time for capturing the interest and imagination and developing the potential of mathematically promising students. This is a time for students to make sense of mathematics, build a solid foundation and enthusiasm, and set the course for the highest levels of mathematics in the future. This is a time to explore their…

Inquiring the Most Critical Teacher's Technology Education Competences in the Highest Efficient Technology Education Learning Organization

ERIC Educational Resources Information Center

Yung-Kuan, Chan; Hsieh, Ming-Yuan; Lee, Chin-Feng; Huang, Chih-Cheng; Ho, Li-Chih

2017-01-01

Under the hyper-dynamic education situation, this research, in order to comprehensively explore the interplays between Teacher Competence Demands (TCD) and Learning Organization Requests (LOR), cross-employs the data refined method of Descriptive Statistics (DS) method and Analysis of Variance (ANOVA) and Principal Components Analysis (PCA)…

Towards a Marketing Communication Recruitment Plan for the Rowan University Educational Leadership Doctoral Program

ERIC Educational Resources Information Center

Kanyi, Titus Kamau

2009-01-01

Doctoral studies are at the apex of the education system. Attracting, recruiting, enrolling, and graduating the best suited students in doctoral education is, therefore, critical in ensuring the highest academic standards and service to society. Focusing on Rowan University's Doctor of Education (Ed.D.) in Educational Leadership program, this…

Improving Infant Exposure and Health Risk Estimates: Using Serum Data to Predict Polybrominated Diphenyl Ether Concentrations in Breast Milk

EPA Science Inventory

Women in the United States have breast milk concentrations of polybrominated diphenyl ethers (PBDEs) that are among the highest in the world, leading to concerns over the potential health implications to breastfeeding infants during critical stages of growth and development. Deve...

Socioeconomic Factors and Vulnerability to Outbreaks of Leptospirosis in Nicaragua

PubMed Central

Bacallao, Jorge; Schneider, Maria Cristina; Najera, Patricia; Aldighieri, Sylvain; Soto, Aida; Marquiño, Wilmer; Sáenz, Carlos; Jiménez, Eduardo; Moreno, Gilberto; Chávez, Octavio; Galan, Deise I.; Espinal, Marcos A.

2014-01-01

Leptospirosis is an epidemic-prone zoonotic disease that occurs worldwide, with more than 500,000 human cases reported annually. It is influenced by environmental and socioeconomic factors that affect the occurrence of outbreaks and the incidence of the disease. Critical areas and potential drivers for leptospirosis outbreaks have been identified in Nicaragua, where several conditions converge and create an appropriate scenario for the development of leptospirosis. The objectives of this study were to explore possible socioeconomic variables related to leptospirosis critical areas and to construct and validate a vulnerability index based on municipal socioeconomic indicators. Municipalities with lower socioeconomic status (greater unsatisfied basic needs for quality of the household and for sanitary services, and higher extreme poverty and illiteracy rates) were identified with the highest leptospirosis rates. The municipalities with highest local vulnerability index should be the priority for intervention. A distinction between risk given by environmental factors and vulnerability to risk given by socioeconomic conditions was shown as important, which also applies to the “causes of outbreaks” and “causes of cases”. PMID:25153463

A Wide Band Gap Polymer with a Deep Highest Occupied Molecular Orbital Level Enables 14.2% Efficiency in Polymer Solar Cells.

PubMed

Li, Sunsun; Ye, Long; Zhao, Wenchao; Yan, Hongping; Yang, Bei; Liu, Delong; Li, Wanning; Ade, Harald; Hou, Jianhui

2018-05-21

To simultaneously achieve low photon energy loss ( E loss ) and broad spectral response, the molecular design of the wide band gap (WBG) donor polymer with a deep HOMO level is of critical importance in fullerene-free polymer solar cells (PSCs). Herein, we developed a new benzodithiophene unit, i.e., DTBDT-EF, and conducted systematic investigations on a WBG DTBDT-EF-based donor polymer, namely, PDTB-EF-T. Due to the synergistic electron-withdrawing effect of the fluorine atom and ester group, PDTB-EF-T exhibits a higher oxidation potential, i.e., a deeper HOMO level (ca. -5.5 eV) than most well-known donor polymers. Hence, a high open-circuit voltage of 0.90 V was obtained when paired with a fluorinated small molecule acceptor (IT-4F), corresponding to a low E loss of 0.62 eV. Furthermore, side-chain engineering demonstrated that subtle side-chain modulation of the ester greatly influences the aggregation effects and molecular packing of polymer PDTB-EF-T. With the benefits of the stronger interchain π-π interaction, the improved ordering structure, and thus the highest hole mobility, the most symmetric charge transport and reduced recombination are achieved for the linear decyl-substituted PDTB-EF-T (P2)-based PSCs, leading to the highest short-circuit current density and fill factor (FF). Due to the high Flory-Huggins interaction parameter (χ), surface-directed phase separation occurs in the P2:IT-4F blend, which is supported by X-ray photoemission spectroscopy results and cross-sectional transmission electron microscope images. By taking advantage of the vertical phase distribution of the P2:IT-4F blend, a high power conversion efficiency (PCE) of 14.2% with an outstanding FF of 0.76 was recorded for inverted devices. These results demonstrate the great potential of the DTBDT-EF unit for future organic photovoltaic applications.

Critical experiments at Sandia National Laboratories : technical meeting on low-power critical facilities and small reactors.

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

Harms, Gary A.; Ford, John T.; Barber, Allison Delo

2010-11-01

Sandia National Laboratories (SNL) has conducted radiation effects testing for the Department of Energy (DOE) and other contractors supporting the DOE since the 1960's. Over this period, the research reactor facilities at Sandia have had a primary mission to provide appropriate nuclear radiation environments for radiation testing and qualification of electronic components and other devices. The current generation of reactors includes the Annular Core Research Reactor (ACRR), a water-moderated pool-type reactor, fueled by elements constructed from UO2-BeO ceramic fuel pellets, and the Sandia Pulse Reactor III (SPR-III), a bare metal fast burst reactor utilizing a uranium-molybdenum alloy fuel. The SPR-IIImore » is currently defueled. The SPR Facility (SPRF) has hosted a series of critical experiments. A purpose-built critical experiment was first operated at the SPRF in the late 1980's. This experiment, called the Space Nuclear Thermal Propulsion Critical Experiment (CX), was designed to explore the reactor physics of a nuclear thermal rocket motor. This experiment was fueled with highly-enriched uranium carbide fuel in annular water-moderated fuel elements. The experiment program was completed and the fuel for the experiment was moved off-site. A second critical experiment, the Burnup Credit Critical Experiment (BUCCX) was operated at Sandia in 2002. The critical assembly for this experiment was based on the assembly used in the CX modified to accommodate low-enriched pin-type fuel in water moderator. This experiment was designed as a platform in which the reactivity effects of specific fission product poisons could be measured. Experiments were carried out on rhodium, an important fission product poison. The fuel and assembly hardware for the BUCCX remains at Sandia and is available for future experimentation. The critical experiment currently in operation at the SPRF is the Seven Percent Critical Experiment (7uPCX). This experiment is designed to provide benchmark reactor physics data to support validation of the reactor physics codes used to design commercial reactor fuel elements in an enrichment range above the current 5% enrichment cap. A first set of critical experiments in the 7uPCX has been completed. More experiments are planned in the 7uPCX series. The critical experiments at Sandia National Laboratories are currently funded by the US Department of Energy Nuclear Criticality Safety Program (NCSP). The NCSP has committed to maintain the critical experiment capability at Sandia and to support the development of a critical experiments training course at the facility. The training course is intended to provide hands-on experiment experience for the training of new and re-training of practicing Nuclear Criticality Safety Engineers. The current plans are for the development of the course to continue through the first part of fiscal year 2011 with the development culminating is the delivery of a prototype of the course in the latter part of the fiscal year. The course will be available in fiscal year 2012.« less

Landscape responses of bats to habitat fragmentation in Atlantic forest of paraguay

USGS Publications Warehouse

Gorresen, P.M.; Willig, M.R.

2004-01-01

Understanding effects of habitat loss and fragmentation on populations or communities is critical to effective conservation and restoration. This is particularly important for bats because they provide vital services to ecosystems via pollination and seed dispersal, especially in tropical and subtropical habitats. Based on more than 1,000 h of survey during a 15-month period, we quantified species abundances and community structure of phyllostomid bats at 14 sites in a 3,000-km2 region of eastern Paraguay. Abundance was highest for Artibeus lituratus in deforested landscapes and for Chrotopterus auritus in forested habitats. In contrast, Artibeus fimbriatus, Carollia perspicillata, Glossophaga soricina, Platyrrhinus lineatus, Pygoderma bilabiatum, and Sturnira lilium attained highest abundance in moderately fragmented forest landscapes. Forest cover, patch size, and patch density frequently were associated with abundance of species. At the community level, species richness was highest in partly deforested landscapes, whereas evenness was greatest in forested habitat. In general, the highest diversity of bats occurred in landscapes comprising moderately fragmented forest habitat. This underscores the importance of remnant habitat patches to conservation strategies.

Effects of repeated bending load at room temperature for composite Nb3Sn wires

NASA Astrophysics Data System (ADS)

Awaji, Satoshi; Watanabe, Kazuo; Katagiri, Kazumune

2003-09-01

In order to realize a react and wind (R&W) method for Nb3Sn wires, the influences of a bending load at room temperature are investigated. Usually, the superconducting wires undergo bending loads at room temperature repeatedly during winding and insulation processes. We define these bending loads as 'pre-bending' treatments. We applied the pre-bending strain of 0 and 0.5% to the highly strengthened CuNb/(Nb, Ti)3Sn wires, and measured the stress/strain properties and critical currents. The improvements of stress dependence of normalized critical current and the increase of the maximum critical current by the pre-bending treatments were found. The model based on the distribution of the local tensile strain as a bending strain describes the experimental results well without the increase of the maximum critical current. When the pre-bending strain was applied, the calculated results indicate that the mechanical properties are improved due to the local work hardening, and hence the stress dependence of Ic increases.

Certification Processes for Safety-Critical and Mission-Critical Aerospace Software

NASA Technical Reports Server (NTRS)

Nelson, Stacy

2003-01-01

This document is a quick reference guide with an overview of the processes required to certify safety-critical and mission-critical flight software at selected NASA centers and the FAA. Researchers and software developers can use this guide to jumpstart their understanding of how to get new or enhanced software onboard an aircraft or spacecraft. The introduction contains aerospace industry definitions of safety and safety-critical software, as well as, the current rationale for certification of safety-critical software. The Standards for Safety-Critical Aerospace Software section lists and describes current standards including NASA standards and RTCA DO-178B. The Mission-Critical versus Safety-Critical software section explains the difference between two important classes of software: safety-critical software involving the potential for loss of life due to software failure and mission-critical software involving the potential for aborting a mission due to software failure. The DO-178B Safety-critical Certification Requirements section describes special processes and methods required to obtain a safety-critical certification for aerospace software flying on vehicles under auspices of the FAA. The final two sections give an overview of the certification process used at Dryden Flight Research Center and the approval process at the Jet Propulsion Lab (JPL).

The Burden of Surgical Diseases on Critical Care Services at a Tertiary Referral Hospital in Sub-Saharan Africa

PubMed Central

Tomlinson, Jared; Haac, Bryce; Kadyaudzu, Clement; Samuel, Jonathan C; Campbell, Emilia LP; Lee, Clara; Charles, Anthony G

2013-01-01

In many developing countries including those of sub-Saharan Africa care of the critically ill is poorly developed. We therefore sought to elucidate the characteristics and outcomes of critically ill patients to better define the burden of disease and identify strategies for improving care. We conducted a cross sectional observation study of patients admitted to the intensive care unit at Kamuzu Central Hospital in 2010. Demographic, patient characteristics, clinical specialty and outcome data was collected. There were 234 patients admitted during the study period. Older age and admission from trauma, general surgery or medical services were associated with increased mortality. The lowest mortality was among obstetrical and gynecologic patients. Use of the ventilator and transfusions were not associated with increased mortality. Head injured patients had the highest mortality rate among all diagnoses. Rationing of critical care resources using admitting diagnosis or scoring tools can maximize access to critical care services in resource-limited settings. Furthermore, improvements on critical care services will be central to future efforts at reducing surgical morbidity and mortality and improving outcomes in all critically ill patients. PMID:23492923

Electric breakdown during the pulsed current spreading in the sand

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

Vasilyak, L. M., E-mail: vasilyak@ihed.ras.ru; Vetchinin, S. P.; Panov, V. A.

2016-03-15

Processes of spreading of the pulsed current from spherical electrodes and an electric breakdown in the quartz sand are studied experimentally. When the current density on the electrode exceeds the critical value, a nonlinear reduction occurs in the grounding resistance as a result of sparking in the soil. The critical electric field strengths for ionization and breakdown are determined. The ionization-overheating instability is shown to develop on the electrode, which leads to the current contraction and formation of plasma channels.

Educational inequalities in smoking among Japanese adults aged 25-94 years: Nationally representative sex- and age-specific statistics.

PubMed

Tabuchi, Takahiro; Kondo, Naoki

2017-04-01

Few studies have investigated differences in age- and gender-specific educational gradients in tobacco smoking among the whole range of adult age groups. We examined educational inequality in smoking among Japanese adults aged 25-94 years. Using a large nationally representative sample (167,925 men and 186,588 women) in 2010, prevalence of current smoking and heavy smoking among daily smokers and their inequalities attributable to educational attainment were analyzed according to sex and age groups. Among men aged 25-34 years, junior high school graduates had the highest current smoking prevalence at 68.4% (95% confidence interval [CI], 66.0%-70.6%), and graduate school graduates had the lowest at 19.4% (95% CI, 17.2%-21.9%). High school graduates had the second highest current smoking prevalence (e.g., 55.9%; 95% CI, 54.9%-56.8% in men aged 25-34 years). Among men aged 75-94 years, the difference in current smoking across educational categories was small. A similar but steeper educational gradient in current smoking was observed among women. Among women aged 25-34 years, junior high school graduates had the highest current smoking prevalence at 49.3% (95% CI, 46.3%-52.3%), and graduate school graduates had the lowest at 4.8% (95% CI, 2.9%-7.4%). Compared with older age groups, such as 65-94 years, younger age groups, such as 25-54 years, had higher estimates of inequality indicators for educational inequality in both current and heavy smoking in both sexes. Educational inequalities in current and heavy smoking were apparent and large in the young population compared with older generations. The current study provides basic data on educational inequalities in smoking among Japanese adults. Copyright © 2016 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Critical current densities in superconducting Y-Ba-Cu-O prepared by chelating method

NASA Astrophysics Data System (ADS)

Fujisawa, Tadashi; Okuyama, Katsuro; Ohshima, Shigetoshi; Takagi, Akira

1990-10-01

The IDA, NTA, HEDTA, EDTA, TTHA, and DTPA chelating agents have been used to prepare the Y-Ba-Cu-O compounds whose critical current is presently investigated. It is noted that the precursor YBCO prepared from large stability-constant metal complexes (HEDTA, EDTA, DTPA, and TTHA) exhibited very fine and homogeneous particles. The critical current density of a 1 x 4 x 15 mm block of YBCO sintered at 880-910 C for 24 h and subsequently annealed at 500 C in an O2 flow was approximately 500 A/sq cm at 77 K, in zero magnetic field.

[Mortality following cardiac surgery in the National Health Service Hospitals of the Community of Valencia in 2007: a descriptive analysis].

PubMed

Vicente, R; Pajares, A; Vicente, J L; Aparicio, R; Loro, J M; Moreno, I; Soria, A; López, A; Porta, J; de la Fuente, C; Herrera, P; Tur, A; Osseyran, F; Guillén, A; Martí, F; Llagunes, J; Mateo, E; Aguar, F; Peña, J J; Marqués, J I; Ripoll, A; Reina, C; Ferrandis, P; Muedra, V; Llopis, E; Cantó, M; García, C

2010-02-01

To analyze clinical records of cardiac surgery patients in an attempt to identify factors associated with mortality in the postoperative critical care units of the public health service hospitals in the Community of Valencia, Spain, in 2007. Retrospective study of cases from January 1, 2007 to December 31, 2007. The charts of all patients who underwent cardiac surgery with or without extracorporeal circulation were reviewed. A data collection protocol was followed to obtain information on age, sex, body mass index (BMI), presurgical risk factors, type of surgery, duration of extracorporeal circulation, duration of ischemia, cause of death, and length of stay in the postoperative critical care unit. The study population consisted of 2113 patients at 5 public hospitals; 124 patients (70 men, 54 women) died. The mean (SD) age was 70 (9.43) years (range, 36-91 years). The mean BMI was 28.19 kg/m2 (maximum, 42 kg/m2). The mean Euroscore was 21.92 (maximum, 94.29). Hypertension was present as a preoperative risk factor in most patients (74.2%); dyslipidemia was present in 51.6%, diabetes mellitus in 38.7%, stroke in 73%, and renal failure in 2.4%. It was noteworthy was that the group who underwent coronary revascularization had the highest mortality rate (nearly 35% of the 124 patients). The next highest mortality rate (19.4%) was in patients who had combined procedures (valve repair or substitution plus coronary revascularization). Mortality was 18.5% in the group undergoing aortic valve surgery and 11.3% in those undergoing mitral valve surgery. The mean duration of extracorporeal circulation was 148.63 minutes. The mean duration of myocardial ischemia was 94.91 minutes. The most frequent cause of death was cardiogenic shock (54.8%). This was followed by distributive shock (29.8%) and hemorrhagic shock (8.9%). The mean length of stay in the postoperative critical care unit was 13.6 days. Overall mortality was 5.87%. The highest mortality rate among cardiac surgery patients in postoperative critical care units in hospitals in the Community of Valencia in 2007 was in patients who underwent coronary revascularization. The most prevalent preoperative risk factor was hypertension. Cardiogenic shock and distributive shock were the most frequent causes of death in these patients. A system for classifying risk is needed in order to predict mortality in critical care units and improve perioperative care.

Lunar Metal Oxide Electrolysis with Oxygen and Photovoltaic Array Production Applications

NASA Technical Reports Server (NTRS)

Curreri, P. A.; Ethridge, E.; Hudson, S.; Sen, S.

2006-01-01

This paper presents the results of a Marshall Space Flight Center funded effort to conduct an experimental demonstration of the processing of simulated lunar resources by the molten oxide electrolysis (MOE) process to produce oxygen and metal from lunar resources to support human exploration of space. Oxygen extracted from lunar materials can be used for life support and propellant, and silicon and metallic elements produced can be used for in situ fabrication of thin-film solar cells for power production. The Moon is rich in mineral resources, but it is almost devoid of chemical reducing agents, therefore, molten oxide electrolysis, MOE, is chosen for extraction, since the electron is the most practical reducing agent. MOE was also chosen for following reasons. First, electrolytic processing offers uncommon versatility in its insensitivity to feedstock composition. Secondly, oxide melts boast the twin key attributes of highest solubilizing capacity for regolith and lowest volatility of any candidate electrolytes. The former is critical in ensuring high productivity since cell current is limited by reactant solubility, while the latter simplifies cell design by obviating the need for a gas-tight reactor to contain evaporation losses as would be the case with a gas or liquid phase fluoride reagent operating at such high temperatures. In the experiments reported here, melts containing iron oxide were electrolyzed in a low temperature supporting oxide electrolyte (developed by D. Sadoway, MIT). The production of oxygen and reduced iron were observed. Electrolysis was also performed on the supporting electrolyte with JSC-1 Lunar Simulant. The cell current for the supporting electrolyte alone is negligible while the current for the electrolyte with JSC-1 shows significant current and a peak at about -0.6 V indicating reductive reaction in the simulant.

Parent-child acculturation profiles as predictors of Chinese American adolescents' academic trajectories.

PubMed

Kim, Su Yeong; Wang, Yijie; Chen, Qi; Shen, Yishan; Hou, Yang

2015-06-01

Acculturation plays a critical role in the adjustment of Asian Americans, as a large proportion of them are immigrants in the US. However, little is known about how acculturation influences Asian American adolescents' academic trajectories over time. Using a longitudinal sample of 444 Chinese American families (54% female children), the current study explored the effect of mothers', fathers', and adolescents' individual acculturation profiles and parent-child acculturation dissonance on adolescents' academic trajectories from 8th to 12th grade. Academic performance was measured by grade point average (GPA), and by standardized test scores in English language arts (ELA) and Math every year. Latent growth modeling analyses showed that adolescents with a Chinese-oriented father showed faster decline in GPA, and Chinese-oriented adolescents had lower initial ELA scores. Adolescents whose parents had American-oriented acculturation profiles tended to have lower initial Math scores. These results suggest that Chinese and American profiles may be disadvantageous for certain aspects of academic performance, and bicultural adolescents and/or adolescents with bicultural parents are best positioned to achieve across multiple domains. In terms of the role of parent-child acculturation dissonance on academic trajectories, the current study highlighted the importance of distinguishing among different types of dissonance. Adolescents who were more Chinese-oriented than their parents tended to have the lowest initial ELA scores, and adolescents experiencing more normative acculturation dissonance (i.e., who were more American-oriented than their parents) had the highest initial ELA scores. No effects of parent-child acculturation dissonance were observed for GPAs or standardized Math scores. Altogether, the current findings add nuances to the current understanding of acculturation and adolescent adjustment.

Parent-Child Acculturation Profiles as Predictors of Chinese American Adolescents’ Academic Trajectories

PubMed Central

Kim, Su Yeong; Wang, Yijie; Chen, Qi; Shen, Yishan; Hou, Yang

2014-01-01

Acculturation plays a critical role in the adjustment of Asian Americans, as a large proportion of them are immigrants in the U.S. However, little is known about how acculturation influences Asian American adolescents’ academic trajectories over time. Using a longitudinal sample of 444 Chinese American families (54% female children), the current study explored the effect of mothers’, fathers’, and adolescents’ individual acculturation profiles and parent-child acculturation dissonance on adolescents’ academic trajectories from 8th to 12th grade. Academic performance was measured by Grade Point Average (GPA), and by standardized test scores in English Language Arts (ELA) and Math every year. Latent growth modeling analyses showed that adolescents with a Chinese-oriented father showed faster decline in GPA, and Chinese-oriented adolescents had lower initial ELA scores. Adolescents whose parents had American-oriented acculturation profiles tended to have lower initial Math scores. These results suggest that Chinese and American profiles may be disadvantageous for certain aspects of academic performance, and bicultural adolescents and/or adolescents with bicultural parents are best positioned to achieve across multiple domains. In terms of the role of parent-child acculturation dissonance on academic trajectories, the current study highlighted the importance of distinguishing among different types of dissonance. Adolescents who were more Chinese-oriented than their parents tended to have the lowest initial ELA scores, and adolescents experiencing more normative acculturation dissonance (i.e., who were more American-oriented than their parents) had the highest initial ELA scores. No effects of parent-child acculturation dissonance were observed for GPAs or standardized Math scores. Altogether, the current findings add nuances to the current understanding of acculturation and adolescent adjustment. PMID:24820295

Critical Theory-Based Approaches in Geography Teaching Departments in Turkey

ERIC Educational Resources Information Center

Bilgili, Münür

2018-01-01

The aim of this study is to understand the relationships between critical theory-based approaches and its implementations in geography teaching departments in Turkey. Critical theory dates back to 1930s and has developed over time aiming to deal with institutions, culture and society through critical lens. Currently, critical theory-based research…

War, Critical Thinking, and Self-Understanding

ERIC Educational Resources Information Center

Noddings, Nel

2004-01-01

Can students learn to think critically if they are not asked to engage with critical issues? Fostering critical thinking is frequently stated as a fundamental aim of education, and yet many teachers report that they have been forbidden to discuss such critical issues as current wars, religion, and cultural differences in styles of parenting. The…

Neural network based automatic limit prediction and avoidance system and method

NASA Technical Reports Server (NTRS)

Calise, Anthony J. (Inventor); Prasad, Jonnalagadda V. R. (Inventor); Horn, Joseph F. (Inventor)

2001-01-01

A method for performance envelope boundary cueing for a vehicle control system comprises the steps of formulating a prediction system for a neural network and training the neural network to predict values of limited parameters as a function of current control positions and current vehicle operating conditions. The method further comprises the steps of applying the neural network to the control system of the vehicle, where the vehicle has capability for measuring current control positions and current vehicle operating conditions. The neural network generates a map of current control positions and vehicle operating conditions versus the limited parameters in a pre-determined vehicle operating condition. The method estimates critical control deflections from the current control positions required to drive the vehicle to a performance envelope boundary. Finally, the method comprises the steps of communicating the critical control deflection to the vehicle control system; and driving the vehicle control system to provide a tactile cue to an operator of the vehicle as the control positions approach the critical control deflections.

Numerical simulation of inductive method for determining spatial distribution of critical current density

NASA Astrophysics Data System (ADS)

Kamitani, A.; Takayama, T.; Tanaka, A.; Ikuno, S.

2010-11-01

The inductive method for measuring the critical current density jC in a high-temperature superconducting (HTS) thin film has been investigated numerically. In order to simulate the method, a non-axisymmetric numerical code has been developed for analyzing the time evolution of the shielding current density. In the code, the governing equation of the shielding current density is spatially discretized with the finite element method and the resulting first-order ordinary differential system is solved by using the 5th-order Runge-Kutta method with an adaptive step-size control algorithm. By using the code, the threshold current IT is evaluated for various positions of a coil. The results of computations show that, near a film edge, the accuracy of the estimating formula for jC is remarkably degraded. Moreover, even the proportional relationship between jC and IT will be lost there. Hence, the critical current density near a film edge cannot be estimated by using the inductive method.

Comprehensive Nuclear-Test-Ban Treaty: Background and Current Developments

DTIC Science & Technology

2008-04-30

resumed testing, and has no plans to test. It has reduced the time needed to conduct a nuclear test. Critics raised concerns about the implications of...lieu of the current treaty.1 On October 24, Senator Jon Kyl delivered a speech critical of the CTBT and of Section 3122 in H.R. 1585, the FY2008...2007. Critics expressed concern about the implications of these policies for testing and new weapons. A statement by Physicians for Social

Determination of Critical Parameters Based on the Intensity of Transmitted Light Around Gas-Liquid Interface: Critical Parameters of CO

NASA Astrophysics Data System (ADS)

Nakayama, Masaki; Katano, Hiroaki; Sato, Haruki

2014-05-01

A precise determination of the critical temperature and density for technically important fluids would be possible on the basis of the digital image for the visual observation of the phase boundary in the vicinity of the critical point since the sensitivity and resolution are higher than those of naked eyes. In addition, the digital image can avoid the personal uncertainty of an observer. A strong density gradient occurs in a sample cell at the critical point due to gravity. It was carefully assessed to determine the critical density, where the density profile in the sample cell can be observed from the luminance profile of a digital image. The density-gradient profile becomes symmetric at the critical point. One of the best fluids, whose thermodynamic properties have been measured with the highest reliability among technically important fluids, would be carbon dioxide. In order to confirm the reliability of the proposed method, the critical temperature and density of carbon dioxide were determined using the digital image. The critical temperature and density values of carbon dioxide are ( and ( kg m, respectively. The critical temperature and density values agree with the existing best values within estimated uncertainties. The reliability of the method was confirmed. The critical pressure, 7.3795 MPa, corresponding to the determined critical temperature of 304.143 K is also proposed. A new set of parameters for the vapor-pressure equation is also provided.

The mediating role of self-criticism and dependency in the association between perceptions of maternal caring and depressive symptoms.

PubMed

Campos, Rui C; Besser, Avi; Blatt, Sidney J

2010-12-01

This study examined a theoretically based mediation model including participants' perceptions of early relationships with their mother, self-criticism, dependency, and current depressive symptoms. We expect that (a) early relationships characterized by low levels of care and high levels of overprotection will be positively associated with both current depressive state and self-criticism and dependency; (b) high levels of self-criticism and dependency will be positively associated with depressive symptoms; and (c) self-criticism and dependency will play a mediating role in the association between participants' perceptions of early relationships characterized by low levels of care and high levels of overprotection and their current depressive symptoms. A nonclinical community sample of 200 Portuguese adults participated in the study. Perceptions of early relationships were measured using the mother scales of the Parental Bonding Instrument (Parker et al. [1979: Br J Med Psychol 52:1-10]), levels of self-criticism and dependency were measured using the Depressive Experiences Questionnaire (Blatt et al. [1976: J Abn Psy 6:383-389]), and depressive symptoms were measured using the Center for the Epidemiological Studies of Depression Scale (Radloff [1977: Appl Psychol Meas 1:385-401]. Structural equation modeling showed that the link between participants' perceptions of early caretaking relationships with their mothers and their current depressive symptoms is mediated by high levels of self-criticism--a personality trait associated with vulnerability to depression--but not Dependency. However, an ancillary analysis indicated that the link between participants' perceptions of early maternal overprotective relationships and their current depressive symptoms is mediated by high levels of Neediness. Findings underscore the role of perceived early relationships in psychological vulnerability to depression among highly self-critical and among highly needy individuals and highlight the negative role played by perceived mothers' early dysfunctional practices, characterized by low levels of caring and high levels of overprotection, for the self-critical vulnerability to depression and by perceived mothers' high levels of overprotection, for the neediness vulnerability to depression. These potential causal mechanisms warrant longitudinal evaluation. Theoretical and clinical implications of the findings are discussed.

Critical current density in wire drawn and hydrostatically extruded Nb-Ti superconductors

NASA Technical Reports Server (NTRS)

Alterovitz, S. A.; Woollam, J. A.; Collings, E. W.

1979-01-01

Critical current studies have been made on copper-clad Nb-Ti composite wire prepared under area reductions of 100:1 and 10,000:1 by hydrostatic extrusion (HE), wire drawing and HE plus drawing. Comparative evaluation of the thermomechanical processing equivalent of HE was performed.

AEIS Policy vs. Site-Based Management: Research Agenda Implications.

ERIC Educational Resources Information Center

Nash, John B.

This paper examines the problems of centralized academic-indicator systems in light of the move toward site-based management. Problems with current practice are examined in the framework of critical inquiry. Alternatives to current accountability guidelines are presented that harmonize positivism with critical inquiry, while respecting both local…

Transformative Critique: What Confucianism Can Contribute to Contemporary Education

ERIC Educational Resources Information Center

Sigurðsson, Geir

2017-01-01

Critical thinking is currently much celebrated in the contemporary West and beyond, not least in higher education. Tertiary education students are generally expected to adopt a critical attitude in order to become responsible and constructive participants in the development of modern democratic society. Currently, the perceived desirability of…

Effect of annealing high-dose heavy-ion irradiated high-temperature superconductor wires

NASA Astrophysics Data System (ADS)

Strickland, N. M.; Wimbush, S. C.; Kluth, P.; Mota-Santiago, P.; Ridgway, M. C.; Kennedy, J. V.; Long, N. J.

2017-10-01

Heavy-ion irradiation of high-temperature superconducting thin films has long been known to generate damage tracks of amorphized material that are of close-to-ideal dimension to effectively contribute to pinning of magnetic flux lines and thereby enhance the in-field critical current. At the same time, though, the presence of these tracks reduces the superconducting volume fraction available to transport current while the irradiation process itself generates oxygen depletion and disorder in the remaining superconducting material. We have irradiated commercially available superconducting coated conductors consisting of a thick film of (Y,Dy)Ba2Cu3O7 deposited on a buffered metal tape substrate in a continuous reel-to-reel process. Irradiation was by 185 MeV 197Au ions. A high fluence of 3 × 1011 ions/cm2 was chosen to emphasize the detrimental effects. The critical current was reduced following this irradiation, but annealing at relatively low temperatures of 200 °C and 400 °C substantially restore the critical current of the irradiated material. At high fields and high temperatures there is a net benefit of critical current compared to the untreated material.

Systematic overview and critical appraisal of meta-analyses of interventions in intensive care medicine.

PubMed

Koster, T M; Wetterslev, J; Gluud, C; Keus, F; van der Horst, I C C

2018-05-24

Meta-analysed intervention effect estimates are perceived to represent the highest level of evidence. However, such effects and the randomized clinical trials which are included in them need critical appraisal before the effects can be trusted. Critical appraisal of a predefined set of all meta-analyses on interventions in intensive care medicine to assess their quality and assessed the risks of bias in those meta-analyses having the best quality. We conducted a systematic search to select all meta-analyses of randomized clinical trials on interventions used in intensive care medicine. Selected meta-analyses were critically appraised for basic scientific criteria, (1) presence of an available protocol, (2) report of a full search strategy, and (3) use of any bias risk assessment of included trials. All meta-analyses which qualified these criteria were scrutinized by full "Risk of Bias in Systematic Reviews" ROBIS evaluation of 4 domains of risks of bias, and a "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" PRISMA evaluation. We identified 467 meta-analyses. A total of 56 meta-analyses complied with these basic scientific criteria. We scrutinized the risks of bias in the 56 meta-analyses by full ROBIS evaluation and a PRISMA evaluation. Only 4 meta-analyses scored low risk of bias in all the 4 ROBIS domains and 41 meta-analyses reported all 27 items of the PRISMA checklist. In contrast with what might be perceived as the highest level of evidence only 0.9% of all meta-analyses were judged to have overall low risk of bias. © 2018 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

['I'm worthless' and other forms of self-criticism: Current knowledge and therapeutic interventions].

PubMed

Maillard, Pauline; Kramer, Ueli

2015-01-01

Self-criticism is considered as a harsh or punitive evaluation of the self. It is omnipresent in culture, in daily life as well as in psychotherapy. Self-criticism can lead to question oneself but can also open new perspectives and guide us. However, it can become excessive, rigid, and might turn out to be deleterious. This present article focuses on the concept of self-criticism in clinical psychology and psychotherapy and aims to review current knowledge about this topic. First, its definition and the reasons for its development in individuals will be presented. Second, a description of the links between self-criticism and psychopathology will be made, in particular regarding depression. Finally, the third part of this article will be dedicated to the therapeutic interventions that can reduce self-criticism.

Staying at the Top: Playing Position and Performance Affect Career Length in Professional Sport

ERIC Educational Resources Information Center

Baker, Joseph; Koz, Dan; Kungl, Ann-Marie; Fraser-Thomas, Jessica; Schorer, Jorg

2013-01-01

In an effort to understand the process of skill acquisition and decline, researchers have largely neglected a critical aspect of this development--maximizing time at the highest levels of achievement. This study examined length of career for professional athletes in basketball, football, ice hockey, and baseball and considers whether career length…

Advanced sorting technologies for optimal wood products and woody biomass utilization

Treesearch

Xiping Wang

2012-01-01

Forest materials represent great potential for advancing our goals in the 21st century for sustainable building, energy independence, and carbon sequestration. A critical component of an improved system for producing bioproducts and bioenergr from forest materials is the ability to sort trees, stems, and logs into end-product categories that represent their highest...

"Caritas" in the Classroom: The Opening of the American Student's Heart.

ERIC Educational Resources Information Center

Lawry, John D.

1990-01-01

The quality of the student-teacher relationship is critical in opening the heart and mind. The highest form of learning occurs when the teacher loves and accepts the student so fully that the student feels safe enough to go within to see himself/herself and emerge with new answers about his/her life. (MSE)

The Computing Alliance of Hispanic-Serving Institutions: Supporting Hispanics at Critical Transition Points

ERIC Educational Resources Information Center

Gates, Ann Quiroz; Hug, Sarah; Thiry, Heather; Alo, Richard; Beheshti, Mohsen; Fernandez, John; Rodriguez, Nestor; Adjouadi, Malek

2011-01-01

Hispanics have the highest growth rates among all groups in the U.S., yet they remain considerably underrepresented in computing careers and in the numbers who obtain advanced degrees. Hispanics constituted about 7% of undergraduate computer science and computer engineering graduates and 1% of doctoral graduates in 2007-2008. The small number of…

On Being Critical: Uniting Theory and Practice through Emancipatory Action Research

ERIC Educational Resources Information Center

Ledwith, Margaret

2007-01-01

This paper engages with some of the specific issues that challenge critical practice. My argument is related to the Carr and Kemmis debate on "staying critical" and to ideas expressed in my current book, "Community Development: A Critical Approach." I refer to critical practice as any practice that has a transformative social justice intention,…

Utilization of low temperatures in electrical machines

NASA Astrophysics Data System (ADS)

Kwasniewska-Jankowicz, L.; Mirski, Z.

1983-09-01

The dimensions of conventional and superconducting direct and alternating current generators are compared and the advantages of using superconducting magnets are examined. The critical temperature, critical current, and critical magnetic field intensity of superconductors in an induction winding are discussed as well as the mechanical properties needed for bending connectors at small radii. Investigations of cryogenic cooling, cryostats, thermal insulation and rotary seals are reported as well as results of studies of the mechanical properties of austenitic Cr-Ni steels, welded joints and plastics for insulation.

Critical Thinking and the Danger of Intellectual Conformity.

ERIC Educational Resources Information Center

Walter, Kerry S.

1987-01-01

Although the goals of critical thinking are to foster critical ability and broad-mindedness, it tends to encourage absolutism, promote passivity, and breed intolerance. The current concentration on critical thinking's reductionism should be balanced with the teaching of alternative approaches to understanding knowledge and reality. (Author/LB)

MA transmutation performance in the optimized MYRRHA

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

Malambu, E.; Van den Eynde, G.; Fernandez, R.

MYRRHA (multi-purpose hybrid research reactor for high-tech applications) is a multipurpose research facility currently being developed at SCK-CEN. It will be able to work in both critical and subcritical modes and, cooled by lead-bismuth eutectic. In this paper the minor actinides (MA) transmutation capabilities of MYRRHA are investigated. (Pu + Am, U) MOX fuel and (Np + Am + Cm, Pu) Inert Matrix Fuel test samples have been loaded in the central channel of the MYRRHA critical core and have been irradiated during five cycles, each one consisting of 90 days of operation at 100 MWth and 30 days ofmore » shutdown. The reactivity worth of the test fuel assembly was about 1.1 dollar. A wide range of burn-up level has been achieved, extending from 42 to 110 MWd/kg HM, the samples with lower MA-to-Pu ratios reaching the highest burn-up. This study has highlighted the importance of the initial MA content, expressed in terms of MA/Pu ratio, on the transmutation rate of MA elements. For (Pu + Am, U) MOX fuel samples, a net build-up of MA is observed when the initial content of MA is very low (here, 1.77 wt% MA/Pu) while a net decrease in MA is observed in the sample with an initial content of 5 wt%. This suggests the existence of some 'equilibrium' initial MA content value beyond which a net transmutation is achievable.« less

Precise time and time interval applications to electric power systems

NASA Technical Reports Server (NTRS)

Wilson, Robert E.

1992-01-01

There are many applications of precise time and time interval (frequency) in operating modern electric power systems. Many generators and customer loads are operated in parallel. The reliable transfer of electrical power to the consumer partly depends on measuring power system frequency consistently in many locations. The internal oscillators in the widely dispersed frequency measuring units must be syntonized. Elaborate protection and control systems guard the high voltage equipment from short and open circuits. For the highest reliability of electric service, engineers need to study all control system operations. Precise timekeeping networks aid in the analysis of power system operations by synchronizing the clocks on recording instruments. Utility engineers want to reproduce events that caused loss of service to customers. Precise timekeeping networks can synchronize protective relay test-sets. For dependable electrical service, all generators and large motors must remain close to speed synchronism. The stable response of a power system to perturbations is critical to continuity of electrical service. Research shows that measurement of the power system state vector can aid in the monitoring and control of system stability. If power system operators know that a lightning storm is approaching a critical transmission line or transformer, they can modify operating strategies. Knowledge of the location of a short circuit fault can speed the re-energizing of a transmission line. One fault location technique requires clocks synchronized to one microsecond. Current research seeks to find out if one microsecond timekeeping can aid and improve power system control and operation.

Flexible carbon micro-supercapacitors prepared by direct cw-laser writing

NASA Astrophysics Data System (ADS)

Cai, Jinguang; Watanabe, Akira

2016-03-01

Micro-/nano-scale power supply units with high energy and high power densities are critical components for the development of compact miniaturized portable electronic devices. Supercapacitors have attracted many research attentions due to their high power density, robust cycle performance, pollution-free operation, and maintenance-free features. Besides, the properties of small size, light weight, and flexibility are also required. On-chip microsupercapacitors (MSCs) have the potential acting as power supply units in portable devices, due to their simplified packaging processes and compatibility to the integrated circuits. However, the fabrication methods and materials should be cost-effective, scalable, and compatible to current electronic industry. Carbon materials own high specific surface areas, electrochemical stability, and high electrical conductivity, which are critical parameters for high-power supercapacitors. Moreover, the high mechanical tolerance makes them good candidates for flexible wearable devices. Therefore, MSCs based on carbon materials would satisfy the requirements of portable electronics. In this work, we demonstrated the fabrication of carbon MSCs by laser direct writing on commercial polyimide sheets in Ar with lowcost semiconductor cw-laser with a wavelength of 405nm. The obtained structures are macro-nanostructures comprising graphitized and amorphous carbon with relatively smooth surfaces and low resistance, in compared with the structures obtained by laser writing in air. As-prepared micro-supercapacitors show a high capacitance of about 14.9 mF/cm2 at a scanning rate of 10 mV/s, which is comparable to the reported highest capacitance of carbon-based supercapacitors fabricated by pulse-laser writing.

Correlations between critical current density, j{sub c}, critical temperature, T{sub c}, and structural quality of Y{sub 1}B{sub 2}Cu{sub 3}O{sub 7-x} thin superconducting films

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

Chrzanowski, J.; Xing, W.B.; Atlan, D.

1994-12-31

Correlations between critical current density (j{sub c}) critical temperature (T{sub c}) and the density of edge dislocations and nonuniform strain have been observed in YBCO thin films deposited by pulsed laser ablation on (001) LaAlO{sub 3} single crystals. Distinct maxima in j{sub c} as a function of the linewidths of the (00{ell}) Bragg reflections and as a function of the mosaic spread have been found in the epitaxial films. These maxima in j{sub c} indicate that the magnetic flux lines, in films of structural quality approaching that of single crystals, are insufficiently pinned which results in a decreased critical currentmore » density. T{sub c} increased monotonically with improving crystalline quality and approached a value characteristic of a pure single crystal. A strong correlation between j{sub c} and the density of edge dislocations N{sub D} was found. At the maximum of the critical current density the density of edge dislocations was estimated to be N{sub D}{approximately}1-2 x 10{sup 9}/cm{sup 2}.« less

Low energy electron beam processing of YBCO thin films

NASA Astrophysics Data System (ADS)

Chromik, Š.; Camerlingo, C.; Sojková, M.; Štrbík, V.; Talacko, M.; Malka, I.; Bar, I.; Bareli, G.; Jung, G.

2017-02-01

Effects of low energy 30 keV electron irradiation of superconducting YBa2Cu3O7-δ thin films have been investigated by means of transport and micro-Raman spectroscopy measurements. The critical temperature and the critical current of 200 nm thick films initially increase with increasing fluency of the electron irradiation, reach the maximum at fluency 3 - 4 × 1020 electrons/cm2, and then decrease with further fluency increase. In much thinner films (75 nm), the critical temperature increases while the critical current decreases after low energy electron irradiation with fluencies below 1020 electrons/cm2. The Raman investigations suggest that critical temperature increase in irradiated films is due to healing of broken Cusbnd O chains that results in increased carrier's concentration in superconducting CuO2 planes. Changes in the critical current are controlled by changes in the density of oxygen vacancies acting as effective pinning centers for flux vortices. The effects of low energy electron irradiation of YBCO turned out to result from a subtle balance of many processes involving oxygen removal, both by thermal activation and kick-off processes, and ordering of chains environment by incident electrons.

Critical current density enhancement by phase decomposition of YBa 2Cu 4O 8 into YBa 2Cu 3O 7-σ and CuO

NASA Astrophysics Data System (ADS)

Krelaus, J.; Heinemann, K.; Ullmann, B.; Freyhardt, H. C.

1995-02-01

Bulk YBa 2Cu 4O 8 (Y-124) is prepared from YBa 2Cu 3O 7-σ (Y-123) and CuO by a powder-metallurgical method. The superconducting features of the Y-124, in particular critical current densities and activation energies, are measured resistively using a four-probe technique and magnetically using a Faraday magnetometer. In a second step the Y-124 is decomposed at high temperatures. The intragranular critical current density is measured at different annealing times, tA, in order to determine and discuss the characteristics of the jc( tA) curves.

A conceptual framework: redefining forest soil's critical acid loads under a changing climate.

PubMed

McNulty, Steven G; Boggs, Johnny L

2010-06-01

Federal agencies of several nations have or are currently developing guidelines for critical forest soil acid loads. These guidelines are used to establish regulations designed to maintain atmospheric acid inputs below levels shown to damage forests and streams. Traditionally, when the critical soil acid load exceeds the amount of acid that the ecosystem can absorb, it is believed to potentially impair forest health. The excess over the critical soil acid load is termed the exceedance, and the larger the exceedance, the greater the risk of ecosystem damage. This definition of critical soil acid load applies to exposure of the soil to a single, long-term pollutant (i.e., acidic deposition). However, ecosystems can be simultaneously under multiple ecosystem stresses and a single critical soil acid load level may not accurately reflect ecosystem health risk when subjected to multiple, episodic environmental stress. For example, the Appalachian Mountains of western North Carolina receive some of the highest rates of acidic deposition in the eastern United States, but these levels are considered to be below the critical acid load (CAL) that would cause forest damage. However, the area experienced a moderate three-year drought from 1999 to 2002, and in 2001 red spruce (Picea rubens Sarg.) trees in the area began to die in large numbers. The initial survey indicated that the affected trees were killed by the southern pine beetle (Dendroctonus frontalis Zimm.). This insect is not normally successful at colonizing these tree species because the trees produce large amounts of oleoresin that exclude the boring beetles. Subsequent investigations revealed that long-term acid deposition may have altered red spruce forest structure and function. There is some evidence that elevated acid deposition (particularly nitrogen) reduced tree water uptake potential, oleoresin production, and caused the trees to become more susceptible to insect colonization during the drought period. While the ecosystem was not in exceedance of the CAL, long-term nitrogen deposition pre-disposed the forest to other ecological stress. In combination, insects, drought, and nitrogen ultimately combined to cause the observed forest mortality. If any one of these factors were not present, the trees would likely not have died. This paper presents a conceptual framework of the ecosystem consequences of these interactions as well as limited plot level data to support this concept. Future assessments of the use of CAL studies need to account for multiple stress impacts to better understand ecosystem response. Published by Elsevier Ltd.

Polaron-like vortices, dissociation transition, and self-induced pinning in magnetic superconductors

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

Bulaevskii, L. N., E-mail: lnb@lanl.gov; Lin, S.-Z.

2013-09-15

Vortices in magnetic superconductors polarize spins nonuniformly and repolarize them when moving. At a low spin relaxation rate and at low bias currents, vortices carrying magnetic polarization clouds become polaron-like and their velocities are determined by the effective drag coefficient that is significantly bigger than the Bardeen-Stephen (BS) one. As the current increases, vortices release polarization clouds and the velocity as well as the voltage in the I-V characteristics jump to values corresponding to the BS drag coefficient at a critical current J{sub c}. The nonuniform components of the magnetic field and magnetization drop as the velocity increases, resulting inmore » weaker polarization and a discontinuous dynamic dissociation depinning transition. Experimentally, the jump shows up as a depinning transition and the corresponding current at the jump is the depinning current. As the current decreases, on the way back, vortices are retrapped by polarization clouds at the current J{sub r} < J{sub c}. As a result, the polaronic effect suppresses dissipation and enhances the critical current. Borocarbides (RE)Ni{sub 2}B{sub 2}C with a short penetration length and highly polarizable rare earth spins seem to be optimal systems for a detailed study of vortex polaron formation by measuring I-V characteristics. We also propose to use a superconductor-magnet multilayer structure to study polaronic mechanism of pinning with the goal to achieve high critical currents. The magnetic layers should have large magnetic susceptibility to enhance the coupling between vortices and magnetization in magnetic layers while the relaxation of the magnetization should be slow. For Nb and a proper magnet multilayer structure, we estimate the critical current density J{sub c} {approx} 10{sup 9} A/m{sup 2} at the magnetic field B Almost-Equal-To 1 T.« less

Critical current densities of Jelly-Roll and powder metallurgy Nb{sub 3}Al wires as a function of temperature and magnetic field

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

Thieme, C.L.H.; Kim, J.B.; Takayasu, M.

Critical current densities of multi-filamentary Nb{sub 3}Al wire made with the Jelly-Roll process (JR) and mono-core powder metallurgy process (PM) wire were measured as a function of temperature and magnetic field. The temperature dependence of the resistive critical field B{sub c2} was measured in PM wires. There is a significant difference between these resistive B{sub c2} values and the ones determined by Kramer plots. The field dependence of the critical current depends on the manufacturing method. In general, it follows a relationship that falls between pure Kramer and one where the pinning force is inversely proportional with B{sup 2}. Inmore » contrast with Nb{sub 3}Sn no maximum in the bulk pinning force is observed down to 3 T (0.15MxB{sub c2}).« less

Field-dependent critical state of high-Tc superconducting strip simultaneously exposed to transport current and perpendicular magnetic field

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

Xue, Cun; He, An; Yong, Huadong

We present an exact analytical approach for arbitrary field-dependent critical state of high-T{sub c} superconducting strip with transport current. The sheet current and flux-density profiles are derived by solving the integral equations, which agree with experiments quite well. For small transport current, the approximate explicit expressions of sheet current, flux-density and penetration depth for the Kim model are derived based on the mean value theorem for integration. We also extend the results to the field-dependent critical state of superconducting strip in the simultaneous presence of applied field and transport current. The sheet current distributions calculated by the Kim model agreemore » with experiments better than that by the Bean model. Moreover, the lines in the I{sub a}-B{sub a} plane for the Kim model are not monotonic, which is quite different from that the Bean model. The results reveal that the maximum transport current in thin superconducting strip will decrease with increasing applied field which vanishes for the Bean model. The results of this paper are useful to calculate ac susceptibility and ac loss.« less

Ontogeny influences sensitivity to climate change stressors in an endangered fish

PubMed Central

Komoroske, L. M.; Connon, R. E.; Lindberg, J.; Cheng, B. S.; Castillo, G.; Hasenbein, M.; Fangue, N. A.

2014-01-01

Coastal ecosystems are among the most human-impacted habitats globally, and their management is often critically linked to recovery of declining native species. In the San Francisco Estuary, the Delta Smelt (Hypomesus transpacificus) is an endemic, endangered fish strongly tied to Californian conservation planning. The complex life history of Delta Smelt combined with dynamic seasonal and spatial abiotic conditions result in dissimilar environments experienced among ontogenetic stages, which may yield stage-specific susceptibility to abiotic stressors. Climate change is forecasted to increase San Francisco Estuary water temperature and salinity; therefore, understanding the influences of ontogeny and phenotypic plasticity on tolerance to these critical environmental parameters is particularly important for Delta Smelt and other San Francisco Estuary fishes. We assessed thermal and salinity limits in several ontogenetic stages and acclimation states of Delta Smelt, and paired these data with environmental data to evaluate sensitivity to climate-change stressors. Thermal tolerance decreased among successive stages, with larval fish exhibiting the highest tolerance and post-spawning adults having the lowest. Delta Smelt had limited capacity to increase tolerance through thermal acclimation, and comparisons with field temperature data revealed that juvenile tolerance limits are the closest to current environmental conditions, which may make this stage especially susceptible to future climate warming. Maximal water temperatures observed in situ exceeded tolerance limits of juveniles and adults. Although these temperature events are currently rare, if they increase in frequency as predicted, it could result in habitat loss at these locations despite other favourable conditions for Delta Smelt. In contrast, Delta Smelt tolerated salinities spanning the range of expected environmental conditions for each ontogenetic stage, but salinity did impact survival in juvenile and adult stages in exposures over acute time scales. Our results underscore the importance of considering ontogeny and phenotypic plasticity in assessing the impacts of climate change, particularly for species adapted to spatially and temporally heterogeneous environments. PMID:27293629

What are the Outstanding Questions in Biosphere-Atmosphere Exchange?

NASA Astrophysics Data System (ADS)

Katul, G.; Finnigan, J.

2002-12-01

Our answer to this question has three parts. At the highest level human population is now so large (and will grow to 10-12 million by 2050 before stabilizing and reversing) and our capacity to influence the biosphere is so profound that we must now treat human, biophysical and geophysical processes as a single interacting system: the Anthroposphere. The Anthroposphere is a complex adaptive system (CAS) in the sense that action of humans individually or in groups (as large as nations) are a response to an environment that includes not just the geosphere and biosphere but the sum of human interactions as well. These actions, in turn, will change this system that provides critical ecosystem services that we are just now realizing are finite and threatened. At present we lack the tools and understanding even to frame key questions about the Anthroposphere although the emerging discipline of Complex System Science is hinting at ways this might be done. At the next level we address the problems posed by cross-scale interactions central to the state and function of the geosphere and biosphere, where processes at the cellular level, (e.g. photosynthesis and respiration), have consequences on the global level and vice-versa through a sequence of non-linear upscale and downscale interactions. Currently there are large gaps in our understanding of this scale cascade that inhibit our ability to parameterize, model and predict phenomena such as the rapid shifts in climate that recent studies of the paleo record have revealed. In short, we need to quantify the risk that our current actions may cause abrupt climate changes that may then feed upon the Anthrosphere. Unless we can reduce the uncertainty with which we describe quantitatively the non-human parts of the Anthroposphere, the injection of models of human interaction, initially tentative, may reduce our predictive ability to unusable levels. Finally we can detail a set of key processes that are themselves critical to geosphere-biosphere functioning but which are poorly understood as yet.

Ontogeny influences sensitivity to climate change stressors in an endangered fish.

PubMed

Komoroske, L M; Connon, R E; Lindberg, J; Cheng, B S; Castillo, G; Hasenbein, M; Fangue, N A

2014-01-01

Coastal ecosystems are among the most human-impacted habitats globally, and their management is often critically linked to recovery of declining native species. In the San Francisco Estuary, the Delta Smelt (Hypomesus transpacificus) is an endemic, endangered fish strongly tied to Californian conservation planning. The complex life history of Delta Smelt combined with dynamic seasonal and spatial abiotic conditions result in dissimilar environments experienced among ontogenetic stages, which may yield stage-specific susceptibility to abiotic stressors. Climate change is forecasted to increase San Francisco Estuary water temperature and salinity; therefore, understanding the influences of ontogeny and phenotypic plasticity on tolerance to these critical environmental parameters is particularly important for Delta Smelt and other San Francisco Estuary fishes. We assessed thermal and salinity limits in several ontogenetic stages and acclimation states of Delta Smelt, and paired these data with environmental data to evaluate sensitivity to climate-change stressors. Thermal tolerance decreased among successive stages, with larval fish exhibiting the highest tolerance and post-spawning adults having the lowest. Delta Smelt had limited capacity to increase tolerance through thermal acclimation, and comparisons with field temperature data revealed that juvenile tolerance limits are the closest to current environmental conditions, which may make this stage especially susceptible to future climate warming. Maximal water temperatures observed in situ exceeded tolerance limits of juveniles and adults. Although these temperature events are currently rare, if they increase in frequency as predicted, it could result in habitat loss at these locations despite other favourable conditions for Delta Smelt. In contrast, Delta Smelt tolerated salinities spanning the range of expected environmental conditions for each ontogenetic stage, but salinity did impact survival in juvenile and adult stages in exposures over acute time scales. Our results underscore the importance of considering ontogeny and phenotypic plasticity in assessing the impacts of climate change, particularly for species adapted to spatially and temporally heterogeneous environments.

Using remote sensing data to assess salmon habitat status in rivers and floodplains of Puget Sound, USA

NASA Astrophysics Data System (ADS)

Beechie, T. J.; Pess, G. R.; Hall, J.; Timpane-Padgham, B.; Stefankiv, O.; Liermann, M. C.; Fresh, K.; Rowse, M.

2015-12-01

Natural processes create dynamic habitat features in large rivers and floodplains, and past land uses that restrict fluvial processes have altered habitat conditions in those environments in Puget Sound, USA. As a result, Chinook salmon and steelhead are listed as threatened species under the US Endangered Species Act (ESA). To help restore these salmon populations, restoration actions often focus on removing constraints on natural processes to restore fluvial dynamics and ultimately restore critical salmon habitats on floodplains. An important aspect of this restoration effort is monitoring whether habitat conditions are improving as anticipated, yet there are currently few protocols available for monitoring trends in large river and floodplain habitats. We identified several remote-sensing metrics that are indicators of salmon habitat condition, and developed repeatable protocols for measuring those metrics. We then tested their sensitivity to land use change by comparing habitat conditions among land cover classes (developed, agriculture, forested, and mixed). As expected, metrics of habitat complexity or condition such as side-channel length, node density, wood jam area, or riparian buffer widths were highest in forested sites and lowest in agriculture and urban sites. By contrast, percent disconnected floodplain and percent armored banks were highest in developed sites and lowest in forested sites. Our results indicate that remote sensing metrics are sensitive enough to detect differences in habitat status among land cover classes, and therefore help us understand the impact of various land uses on habitat conditions. However, detecting trends in habitat condition through time may be difficult because magnitudes of change through time are very small.

Parental work absenteeism is associated with increased symptom complaints and school absence in adolescent children.

PubMed

Hysing, Mari; Petrie, Keith J; Bøe, Tormod; Sivertsen, Børge

2017-05-12

Previous studies have proposed that having parents out of work may influence adolescent illness behaviour and school attendance. However, prior research investigating this question has been limited by retrospective reporting and case control studies. In a large epidemiological study we investigated whether parental work absence was associated with symptom complaints and increased school absenteeism in adolescents. We analysed data from a large epidemiological study of 10,243 Norwegian adolescents aged 16-19. Participants completed survey at school, which included demographic data, parental work absence and current health complaints. An official registry provided school attendance data. Parental work absence was significantly related to the number of adolescent symptom complaints as well as school absenteeism. Having a father out of work was associated with an increased likelihood of being in the highest quartile of symptom reporting by an odds-ratio of 2.2 and mother by 1.6 (compared to the lowest quartile). Similarly, parental work absenteeism was associated with an increased likelihood of being in the highest quartile for school absence by an odds-ratio of 1.9 for a father being out of work and 1.5 for a mother out of work. We found that the number of adolescent symptom complaints mediated the relationship between parental work absenteeism and school absenteeism. We found that parental work absence was significantly associated with the number of adolescent symptom complaints and school absenteeism. The results suggest that parents may play a critical modelling role in the intergenerational transmission of illness and disability behaviour.

A probabilistic model to predict clinical phenotypic traits from genome sequencing.

PubMed

Chen, Yun-Ching; Douville, Christopher; Wang, Cheng; Niknafs, Noushin; Yeo, Grace; Beleva-Guthrie, Violeta; Carter, Hannah; Stenson, Peter D; Cooper, David N; Li, Biao; Mooney, Sean; Karchin, Rachel

2014-09-01

Genetic screening is becoming possible on an unprecedented scale. However, its utility remains controversial. Although most variant genotypes cannot be easily interpreted, many individuals nevertheless attempt to interpret their genetic information. Initiatives such as the Personal Genome Project (PGP) and Illumina's Understand Your Genome are sequencing thousands of adults, collecting phenotypic information and developing computational pipelines to identify the most important variant genotypes harbored by each individual. These pipelines consider database and allele frequency annotations and bioinformatics classifications. We propose that the next step will be to integrate these different sources of information to estimate the probability that a given individual has specific phenotypes of clinical interest. To this end, we have designed a Bayesian probabilistic model to predict the probability of dichotomous phenotypes. When applied to a cohort from PGP, predictions of Gilbert syndrome, Graves' disease, non-Hodgkin lymphoma, and various blood groups were accurate, as individuals manifesting the phenotype in question exhibited the highest, or among the highest, predicted probabilities. Thirty-eight PGP phenotypes (26%) were predicted with area-under-the-ROC curve (AUC)>0.7, and 23 (15.8%) of these were statistically significant, based on permutation tests. Moreover, in a Critical Assessment of Genome Interpretation (CAGI) blinded prediction experiment, the models were used to match 77 PGP genomes to phenotypic profiles, generating the most accurate prediction of 16 submissions, according to an independent assessor. Although the models are currently insufficiently accurate for diagnostic utility, we expect their performance to improve with growth of publicly available genomics data and model refinement by domain experts.

Effects of occupational illness on labor productivity: A socioeconomic aspect of informal sector workers in urban Bangladesh

PubMed Central

Sarker, Abdur Razzaque; Sultana, Marufa; Mahumud, Rashidul Alam; Ahmed, Sayem; Ahmed, Mohammad Wahid; Hoque, Mohammad Enamul; Islam, Ziaul; Gazi, Rukhsana; Khan, Jahangir A.M.

2016-01-01

Objectives: The informal sector is the dominant area of employment and the economy for any developing country including Bangladesh. The cost of productivity loss due to absence from work or presenteeism with illness has rarely been examined in the Bangladesh context. This current study, therefore, attempted to examine the impact of ill health of informal sector workers on labor productivity, future earning, and healthcare-related expenditure. Methodology: A cross-sectional survey was conducted among three occupational groups of informal workers (rickshaw pullers, shopkeepers and restaurant workers) that were generally found in all urban areas in Bangladesh. A total of 557 informal workers were surveyed for this study. Results: Most of the respondents (57%) reported that they had been affected by some type of illness for the last six months. The overall average healthcare expenditure of informal workers was US$48.34, while restaurant workers expended more (US$53.61). Self reported sickness absenteeism was highest (50.37days) in the case of shop keepers, followed by rickshaw pullers (49.31 days), in the last six months. Considering the income loss due to illness in the past six months, the rickshaw pullers were exposed to the highest income loss (US$197.15), followed by the shop keepers (US$151.39). Conclusions: Although the informal sector contributes the most to the economy of Bangladesh, the workers in this sector have hardly any financial protection. This study provides critical clues to providing financial and social protection to informal sector workers in Bangladesh. PMID:27010089

Effects of occupational illness on labor productivity: A socioeconomic aspect of informal sector workers in urban Bangladesh.

PubMed

Sarker, Abdur Razzaque; Sultana, Marufa; Mahumud, Rashidul Alam; Ahmed, Sayem; Ahmed, Mohammad Wahid; Hoque, Mohammad Enamul; Islam, Ziaul; Gazi, Rukhsana; Khan, Jahangir A M

2016-05-25

The informal sector is the dominant area of employment and the economy for any developing country including Bangladesh. The cost of productivity loss due to absence from work or presenteeism with illness has rarely been examined in the Bangladesh context. This current study, therefore, attempted to examine the impact of ill health of informal sector workers on labor productivity, future earning, and healthcare-related expenditure. A cross-sectional survey was conducted among three occupational groups of informal workers (rickshaw pullers, shopkeepers and restaurant workers) that were generally found in all urban areas in Bangladesh. A total of 557 informal workers were surveyed for this study. Most of the respondents (57%) reported that they had been affected by some type of illness for the last six months. The overall average healthcare expenditure of informal workers was US$48.34, while restaurant workers expended more (US$53.61). Self reported sickness absenteeism was highest (50.37days) in the case of shop keepers, followed by rickshaw pullers (49.31 days), in the last six months. Considering the income loss due to illness in the past six months, the rickshaw pullers were exposed to the highest income loss (US$197.15), followed by the shop keepers (US$151.39). Although the informal sector contributes the most to the economy of Bangladesh, the workers in this sector have hardly any financial protection. This study provides critical clues to providing financial and social protection to informal sector workers in Bangladesh.

Surveillance of healthcare-associated infections in Piemonte, Italy: results from a second regional prevalence study

PubMed Central

2014-01-01

Background A prevalence survey of healthcare-associated infections (HAIs) was previously performed in the Piemonte region in 2000. In the decade following the survey, many studies were performed at both the regional and hospital levels, and training courses were developed to address issues highlighted by the survey. In 2010, a second regional prevalence study was performed. The aim of this paper is to present the results of the second prevalence study and discuss them within the context of the HAI prevention and control programmes that have been implemented in the decade since the original survey was conducted. Methods The study involved all public hospitals in the Piemonte region. Uni- and multivariate analyses were performed to assess the main risk factors associated with HAIs, including both overall and site-specific infections. Results A total of 7841 patients were enrolled: 6.8% were affected by at least one HAI. The highest prevalence of HAIs was found in intensive care units (18.0%, 95% CI 14.0-22.6), while UTIs presented the highest relative frequency (26.7%), followed by respiratory tract infections (21.9%). The age of the patient, hospital size and urinary and central venous catheter status were significantly associated with HAIs. Conclusions The study results showed an increase in HAI prevalence, despite prevention and control efforts, as well as training implemented after the first regional survey. Nevertheless, these data are consistent with the current literature. Furthermore, despite its limits, the prevalence approach remains an important means for involving healthcare workers, emphasising HAIs and revealing critical problems that need be addressed. PMID:24899239

The Importance of Subsurface Production for Carbon Export - Evidence from Past Oceans

NASA Astrophysics Data System (ADS)

Kemp, A. E. S.

2016-02-01

The maxim of the geological concept of uniformitarianism is "the present is the key to the past", but in the context of our temporally and spatially minimal observational record of modern ocean biogeochemical processes, ancient ocean sediments may provide critical evidence of the key species involved in carbon flux. Specifically, laminated marine sediments that preserve the seasonal flux cycle represent "palaeo-sediment traps" that vastly expand our knowledge of the operations of the marine biological carbon pump. Several key subsurface-dwelling diatom taxa, hitherto thought to be biogeochemically insignificant, are dominant components of ancient marine sediments. For example, the sapropels and equivalent horizons that have accumulated in the Mediterranean over the past 5 million years, contain abundant rhizosolenid and hemiaulid diatoms. These deposits contain the highest concentrations of organic carbon and there is extensive evidence that this was produced by subsurface production in a deep chlorophyll maximum. The highly stratified conditions that led to this subsurface production and carbon flux are in contrast to prevailing views that have held upwelling systems as those with the highest potential for export in the global ocean. Similarly, studies of ancient "greenhouse" periods such as the Cretaceous, with highly stratified oceans and which are potential analogues for future climate change, show evidence for extensive subsurface production. Together with emerging evidence from stratified regions of the modern ocean, such as the subtropical gyres, insights from these ancient oceans suggest that a reappraisal is required of current views on key phytoplankton producers and their role the operation of the marine biological carbon pump.

Sputtered magnesium diboride thin films: Growth conditions and surface morphology

NASA Astrophysics Data System (ADS)

O'Brien, April; Villegas, Brendon; Gu, J. Y.

2009-01-01

Magnesium diboride (MgB 2) thin films were deposited on C-plane sapphire substrates by sputtering pure B and Mg targets at different substrate temperatures, and were followed by in situ annealing. A systematic study about the effects of the various growth and annealing parameters on the physical properties of MgB 2 thin films showed that the substrate temperature is the most critical factor that determines the superconducting transition temperature ( Tc), while annealing plays a minor role. There was no superconducting transition in the thin films grown at room temperature without post-annealing. The highest Tc of the samples grown at room temperature after the optimized annealing was 22 K. As the temperature of the substrate ( Ts) increased, Tc rose. However, the maximum Ts was limited due to the low magnesium sticking coefficient and thus the Tc value was limited as well. The highest Tc, 29 K, was obtained for the sample deposited at 180 °C, annealed at 620 °C, and was subsequently annealed a second time at 800 °C. Three-dimensional (3D) AFM images clearly demonstrated that the thin films with no transition, or very low Tc, did not have the well-developed MgB 2 grains while the films with higher Tc displayed the well-developed grains and smooth surface. Although the Tc of sputtered MgB 2 films in the current work is lower than that for the bulk and ex situ annealed thin films, this work presents an important step towards the fabrication of MgB 2 heterostructures using rather simple physical vapor deposition method such as sputtering.

Lifecourse educational status in relation to weight gain in African American women.

PubMed

Coogan, Patricia E; Wise, Lauren A; Cozier, Yvette C; Palmer, Julie R; Rosenberg, Lynn

2012-01-01

Childhood disadvantage has been associated with increased risk of obesity from childhood through adulthood and those who are disadvantaged across the lifecourse are at highest risk. The effect of lifecourse socioeconomic status (SES) is particularly important for Black women due to the higher prevalence of low SES and obesity in Black compared to White women. We assessed associations of lifecourse SES, as indicated by educational status, with adult weight in African American women. We assessed the associations of parental education, current education (education of participant or her spouse), and a combination of parental and current education (lifecourse education) with weight gain among 21,457 women aged < 55 years in the longitudinal Black Women's Health Study, which began in 1995. We estimated the mean difference in weight gain between age 18 and age in 2009, and risk ratios for obesity in 2009, in each level of education compared to the highest level (college graduate). The age- and height-adjusted differences in mean weight gain for the lowest levels of parental and current education compared to the highest levels were 3.29 and 4.49 kg, respectively. The age-adjusted risk ratios for obesity for the lowest level of parental and current education were 1.44 (95% CI 1.32-1.57) and 1.75 (95% CI 1.57-1.95), respectively. Risk of obesity was lowest among those with current education of college graduate, regardless of parental education. Educational level of college graduate may overcome the adverse effects of low parental education on weight gain and obesity risk.

Enhanced critical current density in the pressure-induced magnetic state of the high-temperature superconductor FeSe

PubMed Central

Jung, Soon-Gil; Kang, Ji-Hoon; Park, Eunsung; Lee, Sangyun; Lin, Jiunn-Yuan; Chareev, Dmitriy A.; Vasiliev, Alexander N.; Park, Tuson

2015-01-01

We investigate the relation of the critical current density (Jc) and the remarkably increased superconducting transition temperature (Tc) for the FeSe single crystals under pressures up to 2.43 GPa, where the Tc is increased by ~8 K/GPa. The critical current density corresponding to the free flux flow is monotonically enhanced by pressure which is due to the increase in Tc, whereas the depinning critical current density at which the vortex starts to move is more influenced by the pressure-induced magnetic state compared to the increase of Tc. Unlike other high-Tc superconductors, FeSe is not magnetic, but superconducting at ambient pressure. Above a critical pressure where magnetic state is induced and coexists with superconductivity, the depinning Jc abruptly increases even though the increase of the zero-resistivity Tc is negligible, directly indicating that the flux pinning property compared to the Tc enhancement is a more crucial factor for an achievement of a large Jc. In addition, the sharp increase in Jc in the coexisting superconducting phase of FeSe demonstrates that vortices can be effectively trapped by the competing antiferromagnetic order, even though its antagonistic nature against superconductivity is well documented. These results provide new guidance toward technological applications of high-temperature superconductors. PMID:26548444

In situ hydrostatic pressure induced improvement of critical current density and suppression of magnetic relaxation in Y(Dy0.5)Ba2Cu3O7‑δ coated conductors

NASA Astrophysics Data System (ADS)

Sang, Lina; Gutiérrez, Joffre; Cai, Chuanbing; Dou, Shixue; Wang, Xiaolin

2018-07-01

We report on the effect of in situ hydrostatic pressure on the enhancement of the in-magnetic-field critical current density parallel to the crystallographic c-axis and vortex pinning in epitaxial Y(Dy0.5)Ba2Cu3O7‑δ coated conductors prepared by metal organic deposition. Our results show that in situ hydrostatic pressure greatly enhances the critical current density at high fields and high temperatures. At 80 K and 5 T we observe a ten-fold increase in the critical current density under the pressure of 1.2 GPa, and the irreversibility line is shifted to higher fields without changing the critical temperature. The normalized magnetic relaxation rate shows that vortex creep rates are strongly suppressed due to applied pressure, and the pinning energy is significantly increased based on the collective creep theory. After releasing the pressure, we recover the original superconducting properties. Therefore, we speculate that the in situ hydrostatic pressure exerted on the coated conductor enhances the pinning of existing extended defects. This is totally different from what has been observed in REBa2Cu3O7‑δ melt-textured crystals, where the effect of pressure generates point-like defects.

Unconventional critical state in YBa2Cu3O7-δ thin films with a vortex-pin lattice fabricated by masked He+ ion beam irradiation

NASA Astrophysics Data System (ADS)

Zechner, G.; Mletschnig, K. L.; Lang, W.; Dosmailov, M.; Bodea, M. A.; Pedarnig, J. D.

2018-04-01

Thin superconducting YBa2Cu3O7-δ films are patterned with a vortex-pin lattice consisting of columnar defect regions (CDs) with 180 nm diameter and 300 nm spacing. They are fabricated by irradiation with 75 keV He+ ions through a stencil mask. Peaks of the critical current reveal the commensurate trapping of vortices in domains near the edges of the sample. Upon ramping an external magnetic field, the positions of the critical current peaks are shifted from their equilibrium values to lower magnetic fields in virgin and to higher fields in field-saturated down-sweep curves, respectively. Based on previous theoretical predictions, this irreversibility is interpreted as a nonuniform, terrace-like critical state, in which individual domains are occupied by a constant number of vortices per pinning site. The magnetoresistance, probed at low current densities, is hysteretic and angle dependent and exhibits minima that correspond to the peaks of the critical current. The minima’s positions scale with the component of the magnetic field parallel to the axes of the CDs, as long as the tilted vortices can be accommodated within the CDs. This behavior, different from unirradiated films, confirms that the CDs dominate the pinning.

Al0 0.3Ga 0.7N PN diode with breakdown voltage >1600 V

DOE PAGES

Allerman, A. A.; Armstrong, A. M.; Fischer, A. J.; ...

2016-07-21

Demonstration of Al0 0.3Ga 0.7N PN diodes grown with breakdown voltages in excess of 1600 V is reported. The total epilayer thickness is 9.1 μm and was grown by metal-organic vapour-phase epitaxy on 1.3-mm-thick sapphire in order to achieve crack-free structures. A junction termination edge structure was employed to control the lateral electric fields. A current density of 3.5 kA/cm 2 was achieved under DC forward bias and a reverse leakage current <3 nA was measured for voltages <1200 V. The differential on-resistance of 16 mΩ cm 2 is limited by the lateral conductivity of the n-type contact layer requiredmore » by the front-surface contact geometry of the device. An effective critical electric field of 5.9 MV/cm was determined from the epilayer properties and the reverse current–voltage characteristics. To our knowledge, this is the first aluminium gallium nitride (AlGaN)-based PN diode exhibiting a breakdown voltage in excess of 1 kV. Finally, we note that a Baliga figure of merit (V br 2/R spec,on) of 150 MW/cm 2 found is the highest reported for an AlGaN PN diode and illustrates the potential of larger-bandgap AlGaN alloys for high-voltage devices.« less

Nile tilapia Oreochromis niloticus as a food source in advanced life support systems: Initial considerations

NASA Astrophysics Data System (ADS)

Gonzales, John M.; Brown, Paul B.

2006-01-01

Maintenance of crew health is of paramount importance for long duration space missions. Weight loss, bone and calcium loss, increased exposure to radiation and oxidative stress are critical concerns that need to be alleviated. Tilapia are currently under evaluation as a source of food and their contribution to reducing waste in advanced life support systems (ALSS). The nutritional composition of tilapia whole bodies, fillet, and carcass residues were quantitatively determined. Carbon and nitrogen free-extract percentages were similar among whole body (53.76% and 6.96%, respectively), fillets (47.06% and 6.75%, respectively), and carcass (56.36% and 7.04%, respectively) whereas percentages of N, S, and protein were highest in fillet (13.34, 1.34, and 83.37%, respectively) than whole body (9.27, 0.62, and 57.97%, respectively) and carcass (7.70, 0.39, and 48.15%, respectively). Whole body and fillet meet and/or exceeded current nutritional recommendations for protein, vitamin D, ascorbic acid, and selenium for international space station missions. Whole body appears to be a better source of lipids and n-3 fatty acids, calcium, and phosphorous than fillet. Consuming whole fish appears to optimize equivalent system mass compared to consumption of fillets. Additional research is needed to determine nutritional composition of tilapia whole body, fillet, and carcass when fed waste residues possibly encountered in an ALSS.

High critical current superconducting tapes

DOEpatents

Holesinger, Terry G [Los Alamos, NM; Jia, Quanxi [Los Alamos, NM; Foltyn, Stephen R [Los Alamos, NM

2003-09-23

Improvements in critical current capacity for superconducting film structures are disclosed and include the use of a superconducting RE-BCO layer including a mixture of rare earth metals, e.g., yttrium and europium, where the ratio of yttrium to europium in the RE-BCO layer ranges from about 3 to 1 to from about 1.5 to 1.

Chasing Ambiguity: Critical Reflections on Working with Dance Graduates

ERIC Educational Resources Information Center

Roe, Sarah

2017-01-01

This paper questions whether are we able to foster uncertainty and ambiguity within higher education arts programmes, specifically alongside current institutional demands and embedded pedagogies. If not, then what effect does this have on current dance graduates? I attend to these questions through critical reflections upon my work as a pedagogue,…

Using satellite data to identify the causes of and potential solutions for yield gaps in India’s Wheat Belt

NASA Astrophysics Data System (ADS)

Jain, M.; Singh, Balwinder; Srivastava, A. A. K.; Malik, R. K.; McDonald, A. J.; Lobell, D. B.

2017-09-01

Food security will be increasingly challenged by climate change, natural resource degradation, and population growth. Wheat yields, in particular, have already stagnated in many regions and will be further affected by warming temperatures. Despite these challenges, wheat yields can be increased by improving management practices in regions with existing yield gaps. To identify the magnitude and causes of current yield gaps in India, one of the largest wheat producers globally, we produced 30 meter resolution yield maps from 2001 to 2015 across the Indo-Gangetic Plains (IGP), the nation’s main wheat belt. Yield maps were derived using a new method that translates satellite vegetation indices to yield estimates using crop model simulations, bypassing the need for ground calibration data. This is one of the first attempts to apply this method to a smallholder agriculture system, where ground calibration data are rarely available. We find that yields can be increased by 11% on average and up to 32% in the eastern IGP by improving management to current best practices within a given district. Additionally, if current best practices from the highest-yielding state of Punjab are implemented in the eastern IGP, yields could increase by almost 110%. Considering the factors that most influence yields, later sow dates and warmer temperatures are most associated with low yields across the IGP. This suggests that strategies to reduce the negative effects of heat stress, like earlier sowing and planting heat-tolerant wheat varieties, are critical to increasing wheat yields in this globally-important agricultural region.

Influence of rice field agrochemicals on the ecological status of a tropical stream.

PubMed

Rasmussen, Jes Jessen; Reiler, Emilie Marie; Carazo, Elizabeth; Matarrita, Jessie; Muñoz, Alejandro; Cedergreen, Nina

2016-01-15

Many tropical countries contain a high density of protected ecosystems, and these may often be bordered by intensive agricultural systems. We investigated the chemical and ecological status of a stream connecting an area with conventional rice production and a downstream protected nature reserve; Mata Redonda. Three sites were sampled: 1) an upstream control, 2) in the rice production area and 3) a downstream site in Mata Redonda. We sampled benthic macroinvertebrates and pesticides in water and sediments along with supporting physical and chemical data. Pesticide concentrations in water exceeded current safety thresholds at sites 2 and 3, especially during the rainy season, and sediment associated pesticide concentrations exceeded current safety thresholds in three of six samples. Importantly, the highest predicted pesticide toxicity in sediments was observed at site 3 in the Mata Redonda confirming that the nature reserve received critical levels of pesticide pollution from upstream sections. The currently used macroinvertebrate index in Costa Rica (BMWP-CR) and an adjusted version of the SPecies At Risk index (SPEAR) were not significantly correlated to any measure of anthropogenic stress, but the Average Score Per Taxon (ASPT) index was significantly correlated with the predicted pesticide toxicity (sumTUD.magna), oxygen concentrations and substrate composition. Our results suggest that pesticide pollution was likely involved in the impairment of the ecological status of the sampling sites, including site 3 in Mata Redonda. Based on our results, we give guidance to biomonitoring in Costa Rica and call for increased focus on pesticide transport from agricultural regions to protected areas. Copyright © 2015 Elsevier B.V. All rights reserved.

Prevention of childhood obesity in Spain: a focus on policies outside the health sector. SESPAS report 2010.

PubMed

Franco, Manuel; Sanz, Belén; Otero, Laura; Domínguez-Vila, Adrián; Caballero, Benjamín

2010-12-01

Obesity is currently a global public health problem. Obesity in early life increases the risk of long-term energy imbalance and adult obesity and its comorbidities, type 2 diabetes, and cardiovascular disease. Since infancy and childhood are critical periods for the adoption of food preferences and physical activity, prevention strategies must intervene in these early periods to promote healthy habits and reduce risk behaviors. Trends in the prevalence of childhood obesity and overweight in Spain have continuously increased in the last three decades. Obesity and overweight currently affect 15 and 20% of Spanish children, respectively, and these percentages are among the highest in Europe. Childhood obesity is determined by social and economic factors pertaining to sectors other than the health system, such as advertising, the built environment, education and the school environment, transportation and the food environment. Following the Health in All Policies (HiAP) approach, the authors identified a series of multisector policy changes that may help to prevent and control the current rising trend of childhood obesity in Spain. The HiAP approach acknowledges that social factors including socioeconomic status, gender differences and the work-life balance are important to develop effective policy changes in the prevention of childhood obesity. A key to success in the prevention of childhood obesity in Spain through policy changes will depend on the ability to establish a policy with the explicit and primary goal of improving health outcomes, despite the anticipated resistance from various sectors and stakeholders. Copyright © 2010 SESPAS. Published by Elsevier Espana. All rights reserved.

The ethical dimension in published animal research in critical care: the dark side of our moon.

PubMed

Huet, Olivier; de Haan, Judy B

2014-03-13

The replacement, refinement, and reduction (3Rs) guidelines are the cornerstone of animal welfare practice for medical research. Nowadays, no animal research can be performed without being approved by an animal ethics committee. Therefore, we should expect that any published article would respect and promote the highest standard of animal welfare. However, in the previous issue of Critical Care, Bara and Joffe reported an unexpected finding: animal welfare is extremely poorly reported in critical care research publications involving animal models.This may have a significant negative impact on the reliability of the results and on future funding for our research.The ability of septic shock animal models to translate into clinical studies has been a challenge. Therefore, every means to improve the quality of these models should be pursued. Animal welfare issues should be seen as an additional benefit to achieve this goal. It is therefore critical to draw conclusions from this study to improve the standard of animal welfare in critical care research. This has already been achieved in other fields of research, and we should follow their example.

Quality of the clinical laboratory department in a specialized hospital in Alexandria, Egypt.

PubMed

Elhoseeny, T A; Mohammad, E K

2013-01-01

Assessment and improvement of turnaround times (TAT) as well as customer satisfaction is essential for laboratory quality management. This study in a specialized hospital in Alexandria, Egypt measured the current TAT for outpatient department bilirubin samples and evaluated the satisfaction of physicians with aspects of clinical laboratory services. While the mean TAT for 110 bilirubin tests [58.1 (SD 31.8) min] was within the College of American Pathologists' benchmark, the 90th percentile was long (96.7 min); 62.7% of tests were reported within 60 min. The mean overall satisfaction score of physicians (range 1-5) was 3.46 (SD 0.49). The highest satisfaction rating was for staff courtesy while the lowest ratings were for laboratory management responsiveness, outpatient stat TAT and critical value notification. Quality or reliability of results was judged by physicians as the most important factor (32.3%), followed by routine test TAT (18.5%). Further analysis of the different steps of the TAT would be helpful and follow-up through examining outliers is recommended

Mapping for prevention: GIS models for directing childhood lead poisoning prevention programs.

PubMed Central

Miranda, Marie Lynn; Dolinoy, Dana C; Overstreet, M Alicia

2002-01-01

Environmental threats to children's health--especially low-level lead exposure--are complex and multifaceted; consequently, mitigation of these threats has proven costly and insufficient and has produced economic and racial disparities in exposure among populations. Policy makers, public health officials, child advocates, and others currently lack the appropriate infrastructure to evaluate children's risk and exposure potential across a broad range of risks. Unable to identify where the highest risk of exposure occurs, children's environmental health programs remain mitigative instead of preventive. In this article we use geographic information system spatial analysis of data from blood lead screening, county tax assessors, and the U.S. Census to predict statistically based lead exposure risk levels mapped at the individual tax parcel unit in six counties in North Carolina. The resulting model uses weighted risk factors to spatially locate modeled exposure zones, thus highlighting critical areas for targeted intervention. The methods presented here hold promise for application and extension to the other 94 North Carolina counties and nationally, as well as to other environmental health risks. PMID:12204831

Community Exoplanet Follow-up Program

NASA Technical Reports Server (NTRS)

Howell, Steve

2017-01-01

During the Kepler mission, our team provided the community with the highest resolution images available anywhere of exoplanet host stars. Using speckle interferometry on the 3.5-m WIYN, and 8-m Gemini telescopes, thousands of observations have been obtained reaching the diffraction limit of the telescope. From these public data available at the NASA Exoplanet Archive, numerous publications have resulted and many scientific results have been obtained for exoplanets including the fact that high-resolution imaging is critical to fully characterize the planet host stars and the planets themselves (e.g., planet radius and incident flux). Exoplanet host star observations have also occurred (and continue) for K2 mission candidates with archival data available as well. Observational programs for TESS candidates, WFIRST program stars, and Zodiacal light candidates are currently on-going. Availability to propose or obtain such observations are possible through 1) collaboration with our team, 2) successfully proposing to WIYN or GEMINI for telescope time, or 3) using publically available archival data. This poster will highlight the observational program, how time is allocated and how our queue observational program works, and new features and observational modes that are available now.

Laser-Driven Ion Acceleration from Plasma Micro-Channel Targets

PubMed Central

Zou, D. B.; Pukhov, A.; Yi, L. Q.; Zhou, H. B.; Yu, T. P.; Yin, Y.; Shao, F. Q.

2017-01-01

Efficient energy boost of the laser-accelerated ions is critical for their applications in biomedical and hadron research. Achiev-able energies continue to rise, with currently highest energies, allowing access to medical therapy energy windows. Here, a new regime of simultaneous acceleration of ~100 MeV protons and multi-100 MeV carbon-ions from plasma micro-channel targets is proposed by using a ~1020 W/cm2 modest intensity laser pulse. It is found that two trains of overdense electron bunches are dragged out from the micro-channel and effectively accelerated by the longitudinal electric-field excited in the plasma channel. With the optimized channel size, these “superponderomotive” energetic electrons can be focused on the front surface of the attached plastic substrate. The much intense sheath electric-field is formed on the rear side, leading to up to ~10-fold ionic energy increase compared to the simple planar geometry. The analytical prediction of the optimal channel size and ion maximum energies is derived, which shows good agreement with the particle-in-cell simulations. PMID:28218247

A systematic method of interconnection optimization for dense-array concentrator photovoltaic system.

PubMed

Siaw, Fei-Lu; Chong, Kok-Keong

2013-01-01

This paper presents a new systematic approach to analyze all possible array configurations in order to determine the most optimal dense-array configuration for concentrator photovoltaic (CPV) systems. The proposed method is fast, simple, reasonably accurate, and very useful as a preliminary study before constructing a dense-array CPV panel. Using measured flux distribution data, each CPV cells' voltage and current values at three critical points which are at short-circuit, open-circuit, and maximum power point are determined. From there, an algorithm groups the cells into basic modules. The next step is I-V curve prediction, to find the maximum output power of each array configuration. As a case study, twenty different I-V predictions are made for a prototype of nonimaging planar concentrator, and the array configuration that yields the highest output power is determined. The result is then verified by assembling and testing of an actual dense-array on the prototype. It was found that the I-V curve closely resembles simulated I-V prediction, and measured maximum output power varies by only 1.34%.

Challenges and Prospect of Non-aqueous Non-alkali (NANA) Metal-Air Batteries.

PubMed

Gelman, Danny; Shvartsev, Boris; Ein-Eli, Yair

2016-12-01

Non-aqueous non-alkali (NANA) metal-air battery technologies promise to provide electrochemical energy storage with the highest specific energy density. Metal-air battery technology is particularly advantageous being implemented in long-range electric vehicles. Up to now, almost all the efforts in the field are focused on Li-air cells, but other NANA metal-air battery technologies emerge. The major concern, which the research community should be dealing with, is the limited and rather poor rechargeability of these systems. The challenges we are covering in this review are related to the initial limited discharge capacities and cell performances. By comprehensively reviewing the studies conducted so far, we show that the implementation of advanced materials is a promising approach to increase metal-air performance and, particularly, metal surface activation as a prime achievement leading to respectful discharge currents. In this review, we address the most critical areas that need careful research attention in order to achieve progress in the understanding of the physical and electrochemical processes in non-aqueous electrolytes applied in beyond lithium and zinc air generation of metal-air battery systems.

Prospecting for hyperaccumulators of trace elements: a review.

PubMed

Krzciuk, Karina; Gałuszka, Agnieszka

2015-01-01

Specific plant species that can take up and accumulate abnormally high concentrations of elements in their aboveground tissues are referred to as "hyperaccumulators". The use of this term is justified in the case of enormous element-binding capacity of plants growing in their natural habitats and showing no toxicity symptoms. An increasing interest in the study of hyperaccumulators results from their potential applications in environmental biotechnology (phytoremediation, phytomining) and their emerging role in nanotechnology. The highest number of plant species with confirmed hyperaccumulative properties has been reported for hyperaccumulators of nickel, cadmium, zinc, manganese, arsenic and selenium. More limited data exist for plants accumulating other elements, including common pollutants (chromium, lead and boron) or elements of commercial value, such as copper, gold and rare earth elements. Different approaches have been used for the study of hyperaccumulators - geobotanical, chemical, biochemical and genetic. The chemical approach is the most important in screening for new hyperaccumulators. This article presents and critically reviews current trends in new hyperaccumulator research, emphasizing analytical methodology that is applied in identification of new hyperaccumulators of trace elements and its future perspectives.

Helium temperature measurements in a hot filament magnetic mirror plasma using high resolution Doppler spectroscopy

NASA Astrophysics Data System (ADS)

Knott, S.; McCarthy, P. J.; Ruth, A. A.

2016-09-01

Langmuir probe and spectroscopic diagnostics are used to routinely measure electron temperature and density over a wide operating range in a reconfigured Double Plasma device at University College Cork, Ireland. The helium plasma, generated through thermionic emission from a negatively biased tungsten filament, is confined by an axisymmetric magnetic mirror configuration using two stacks of NdFeB permanent magnets, each of length 20 cm and diameter 3 cm placed just outside the 15 mm water cooling jacket enclosing a cylindrical vacuum vessel of internal diameter 25 cm. Plasma light is analysed using a Fourier Transform-type Bruker spectrometer with a highest achievable resolution of 0.08 cm-1 . In the present work, the conventional assumption of room temperature ions in the analysis of Langmuir probe data from low temperature plasmas is examined critically using Doppler spectroscopy of the 468.6 nm He II line. Results for ion temperatures obtained from spectroscopic data for a variety of engineering parameters (discharge voltage, gas pressure and plasma current) will be presented.

Critical advancements in achieving high power and stable nonprecious metal catalyst–based MEAs for real-world proton exchange membrane fuel cell applications

PubMed Central

Zhou, Yingjie; Bai, Kyoung

2018-01-01

Despite great progress in the development of nonprecious metal catalysts (NPMCs) over the past several decades, the performance and stability of these promising catalysts have not yet achieved commercial readiness for proton exchange membrane fuel cells (PEMFCs). Through rational design of the cathode catalyst layer (CCL), we demonstrate the highest reported performance for an NPMC-based membrane electrode assembly (MEA), achieving a peak power of 570 mW/cm2 under air. This record performance is achieved using a precommercial catalyst for which nearly all pores are <3 nm in diameter, challenging previous beliefs regarding the need for larger catalyst pores to achieve high current densities. This advance is achieved at industrially relevant scales (50 cm2 MEA) using a precommercial NPMC. In situ electrochemical analysis of the CCLs is also used to help gain insight into the degradation mechanism observed during galvanostatic testing. Overall, the performance of this NPMC-based MEA has achieved commercial readiness and will be introduced into an NPMC-based product for portable power applications. PMID:29582018

High-power-density, high-energy-density fluorinated graphene for primary lithium batteries

NASA Astrophysics Data System (ADS)

Zhong, Guiming; Chen, Huixin; Huang, Xingkang; Yue, Hongjun; Lu, Canzhong

2018-03-01

Li/CFx is one of the highest-energy-density primary batteries; however, poor rate capability hinders its practical applications in high-power devices. Here we report a preparation of fluorinated graphene (GFx) with superior performance through a direct gas fluorination. We find that the so-called “semi-ionic” C-F bond content in all C-F bonds presents a more critical impact on rate performance of the GFx in comparison with sp2 C content in the GFx, morphology, structure, and specific surface area of the materials. The rate capability remains excellent before the semi-ionic C-F bond proportion in the GFx decreases. Thus, by optimizing semi-ionic C-F content in our GFx, we obtain the optimal x of 0.8, with which the GF0.8 exhibits a very high energy density of 1073 Wh kg-1 and an excellent power density of 21460 W kg-1 at a high current density of 10 A g-1. More importantly, our approach opens a new avenue to obtain fluorinated carbon with high energy densities without compromising high power densities.

Lessons from a pilot project in cognitive task analysis: the potential role of intermediates in preclinical teaching in dental education.

PubMed

Walker, Judith; von Bergmann, HsingChi

2015-03-01

The purpose of this study was to explore the use of cognitive task analysis to inform the teaching of psychomotor skills and cognitive strategies in clinical tasks in dental education. Methods used were observing and videotaping an expert at one dental school thinking aloud while performing a specific preclinical task (in a simulated environment), interviewing the expert to probe deeper into his thinking processes, and applying the same procedures to analyze the performance of three second-year dental students who had recently learned the analyzed task and who represented a spectrum of their cohort's ability to undertake the procedure. The investigators sought to understand how experts (clinical educators) and intermediates (trained students) overlapped and differed at points in the procedure that represented the highest cognitive load, known as "critical incidents." Findings from this study and previous research identified possible limitations of current clinical teaching as a result of expert blind spots. These findings coupled with the growing evidence of the effectiveness of peer teaching suggest the potential role of intermediates in helping novices learn preclinical dentistry tasks.

Solid-state supercapacitors with rationally designed heterogeneous electrodes fabricated by large area spray processing for wearable energy storage applications.

PubMed

Huang, Chun; Zhang, Jin; Young, Neil P; Snaith, Henry J; Grant, Patrick S

2016-05-10

Supercapacitors are in demand for short-term electrical charge and discharge applications. Unlike conventional supercapacitors, solid-state versions have no liquid electrolyte and do not require robust, rigid packaging for containment. Consequently they can be thinner, lighter and more flexible. However, solid-state supercapacitors suffer from lower power density and where new materials have been developed to improve performance, there remains a gap between promising laboratory results that usually require nano-structured materials and fine-scale processing approaches, and current manufacturing technology that operates at large scale. We demonstrate a new, scalable capability to produce discrete, multi-layered electrodes with a different material and/or morphology in each layer, and where each layer plays a different, critical role in enhancing the dynamics of charge/discharge. This layered structure allows efficient utilisation of each material and enables conservative use of hard-to-obtain materials. The layered electrode shows amongst the highest combinations of energy and power densities for solid-state supercapacitors. Our functional design and spray manufacturing approach to heterogeneous electrodes provide a new way forward for improved energy storage devices.

Laser-Driven Ion Acceleration from Plasma Micro-Channel Targets

NASA Astrophysics Data System (ADS)

Zou, D. B.; Pukhov, A.; Yi, L. Q.; Zhou, H. B.; Yu, T. P.; Yin, Y.; Shao, F. Q.

2017-02-01

Efficient energy boost of the laser-accelerated ions is critical for their applications in biomedical and hadron research. Achiev-able energies continue to rise, with currently highest energies, allowing access to medical therapy energy windows. Here, a new regime of simultaneous acceleration of ~100 MeV protons and multi-100 MeV carbon-ions from plasma micro-channel targets is proposed by using a ~1020 W/cm2 modest intensity laser pulse. It is found that two trains of overdense electron bunches are dragged out from the micro-channel and effectively accelerated by the longitudinal electric-field excited in the plasma channel. With the optimized channel size, these “superponderomotive” energetic electrons can be focused on the front surface of the attached plastic substrate. The much intense sheath electric-field is formed on the rear side, leading to up to ~10-fold ionic energy increase compared to the simple planar geometry. The analytical prediction of the optimal channel size and ion maximum energies is derived, which shows good agreement with the particle-in-cell simulations.

Oxypnictide SmFeAs(O,F) superconductor: a candidate for high-field magnet applications

NASA Astrophysics Data System (ADS)

Iida, Kazumasa; Hänisch, Jens; Tarantini, Chiara; Kurth, Fritz; Jaroszynski, Jan; Ueda, Shinya; Naito, Michio; Ichinose, Ataru; Tsukada, Ichiro; Reich, Elke; Grinenko, Vadim; Schultz, Ludwig; Holzapfel, Bernhard

2013-07-01

The recently discovered oxypnictide superconductor SmFeAs(O,F) is the most attractive material among the Fe-based superconductors due to its highest transition temperature of 56 K and potential for high-field performance. In order to exploit this new material for superconducting applications, the knowledge and understanding of its electro-magnetic properties are needed. Recent success in fabricating epitaxial SmFeAs(O,F) thin films opens a great opportunity to explore their transport properties. Here we report on a high critical current density of over 105 A/cm2 at 45 T and 4.2 K for both main field orientations, feature favourable for high-field magnet applications. Additionally, by investigating the pinning properties, we observed a dimensional crossover between the superconducting coherence length and the FeAs interlayer distance at 30-40 K, indicative of a possible intrinsic Josephson junction in SmFeAs(O,F) at low temperatures that can be employed in electronics applications such as a terahertz radiation source and a superconducting Qubit.

A Systematic Method of Interconnection Optimization for Dense-Array Concentrator Photovoltaic System

PubMed Central

Siaw, Fei-Lu

2013-01-01

This paper presents a new systematic approach to analyze all possible array configurations in order to determine the most optimal dense-array configuration for concentrator photovoltaic (CPV) systems. The proposed method is fast, simple, reasonably accurate, and very useful as a preliminary study before constructing a dense-array CPV panel. Using measured flux distribution data, each CPV cells' voltage and current values at three critical points which are at short-circuit, open-circuit, and maximum power point are determined. From there, an algorithm groups the cells into basic modules. The next step is I-V curve prediction, to find the maximum output power of each array configuration. As a case study, twenty different I-V predictions are made for a prototype of nonimaging planar concentrator, and the array configuration that yields the highest output power is determined. The result is then verified by assembling and testing of an actual dense-array on the prototype. It was found that the I-V curve closely resembles simulated I-V prediction, and measured maximum output power varies by only 1.34%. PMID:24453823

Oxypnictide SmFeAs(O,F) superconductor: a candidate for high–field magnet applications

PubMed Central

Iida, Kazumasa; Hänisch, Jens; Tarantini, Chiara; Kurth, Fritz; Jaroszynski, Jan; Ueda, Shinya; Naito, Michio; Ichinose, Ataru; Tsukada, Ichiro; Reich, Elke; Grinenko, Vadim; Schultz, Ludwig; Holzapfel, Bernhard

2013-01-01

The recently discovered oxypnictide superconductor SmFeAs(O,F) is the most attractive material among the Fe-based superconductors due to its highest transition temperature of 56 K and potential for high-field performance. In order to exploit this new material for superconducting applications, the knowledge and understanding of its electro-magnetic properties are needed. Recent success in fabricating epitaxial SmFeAs(O,F) thin films opens a great opportunity to explore their transport properties. Here we report on a high critical current density of over 105 A/cm2 at 45 T and 4.2 K for both main field orientations, feature favourable for high-field magnet applications. Additionally, by investigating the pinning properties, we observed a dimensional crossover between the superconducting coherence length and the FeAs interlayer distance at 30–40 K, indicative of a possible intrinsic Josephson junction in SmFeAs(O,F) at low temperatures that can be employed in electronics applications such as a terahertz radiation source and a superconducting Qubit. PMID:23823976

[Team approaches to critical bleeding (massive bleeding and transfusion) - chairmen's introductory remarks. Questionnaire survey on current status of hospital clinical laboratories evaluating critical hemorrhage].

PubMed

Kino, Shuichi; Suwabe, Akira

2014-12-01

In 2007, "the Guidelines for Actions against Intraoperative Critical Hemorrhage" were established by the Japanese Society of Anaesthesiologists and the Japanese Society of Blood transfusion and Cell Therapy. The documentation of in-hospital procedures for critical hemorrhage, especially about how to select RBC units, has widely standardized hospital practice. Patients with intraoperative critical hemorrhage sometimes suffer from massive blood loss. In this situation, some patients develop coagulopathy. To treat them, we need to evaluate their coagulation status based on laboratory test results. So, we performed a nationwide questionnaire survey on the current status of hospital clinical laboratories evaluating critical hemorrhage. From the results of this survey, it was recommended that central hospital laboratories should try to reduce the turn-around time required to test for coagulation parameters as much as possible for appropriate substitution therapy. (Review).

Tadpole of the Critically Endangered Sterling's Toothed Toad (Oreolalax sterlingae).

PubMed

Rowley, Jodi J L; Tapley, Benjamin; Chung, Nguyen Thanh; Altig, Ronald

2017-05-31

Sterling's Toothed Toad, Oreolalax sterlingae (Nguyen et al. 2013), was described from near the summit of the highest peak in Vietnam, Mount Fansipan, Lao Cai Province. The species is the only member of the genus in Vietnam and is presently known from a single stream system on Mount Fansipan at about 2800 m elevation. The closest congener occurs more than 200 km away in China (Fei et al. 2010), and the relationship of O. sterlingae within the genus is not known. Because of its extremely small range and profound habitat modifications and pollution at the site, O. sterlingae was recently assessed as Critically Endangered (IUCN SSC 2015).

A statistical study of current-sheet formation above solar active regions based on selforganized criticality

NASA Astrophysics Data System (ADS)

Dimitropoulou, M.; Isliker, H.; Vlahos, L.; Georgoulis, M.; Anastasiadis, A.; Toutountzi, A.

2013-09-01

We treat flaring solar active regions as physical systems having reached the self-organized critical state. Their evolving magnetic configurations in the low corona may satisfy an instability criterion, related to the excession of a specific threshold in the curl of the magnetic field. This imposed instability criterion implies an almost zero resistivity everywhere in the solar corona, except in regions where magnetic-field discontinuities and. hence, local currents, reach the critical value. In these areas, current-driven instabilities enhance the resistivity by many orders of magnitude forming structures which efficiently accelerate charged particles. Simulating the formation of such structures (thought of as current sheets) via a refined SOC cellular-automaton model provides interesting information regarding their statistical properties. It is shown that the current density in such unstable regions follows power-law scaling. Furthermore, the size distribution of the produced current sheets is best fitted by power laws, whereas their formation probability is investigated against the photospheric magnetic configuration (e.g. Polarity Inversion Lines, Plage). The average fractal dimension of the produced current sheets is deduced depending on the selected critical threshold. The above-mentioned statistical description of intermittent electric field structures can be used by collisional relativistic test particle simulations, aiming to interpret particle acceleration in flaring active regions and in strongly turbulent media in astrophysical plasmas. The above work is supported by the Hellenic National Space Weather Research Network (HNSWRN) via the THALIS Programme.

Jordanian TEFL Graduate Students' Use of Critical Thinking Skills (as Measured by the Cornell Critical Thinking Test, Level Z)

ERIC Educational Resources Information Center

Bataineh, Ruba Fahmi; Zghoul, Lamma Hmoud

2006-01-01

This study investigates the critical thinking skills of 50 students currently enrolled in the Master's TEFL Programme at Yarmouk University, Jordan. The Cornell Critical Thinking Test, Level Z is utilised to test the students' use, or lack thereof, of the critical thinking skills of deduction, semantics, credibility, induction, definition and…

Effective Instruction and Assessment Methods That Lead to Gains in Critical Thinking as Measured by the Critical Thinking Assessment Test (CAT)

ERIC Educational Resources Information Center

Leming, Katie P.

2016-01-01

Previous qualitative research on educational practices designed to improve critical thinking has relied on anecdotal or student self-reports of gains in critical thinking. Unfortunately, student self-report data have been found to be unreliable proxies for measuring critical thinking gains. Therefore, in the current interpretivist study, five…

Field-Tuned Superconductor-Insulator Transition with and without Current Bias.

PubMed

Bielejec, E; Wu, Wenhao

2002-05-20

The magnetic-field-tuned superconductor-insulator transition has been studied in ultrathin beryllium films quench condensed near 20 K. In the zero-current limit, a finite-size scaling analysis yields the scaling exponent product nuz = 1.35+/-0.10 and a critical sheet resistance, R(c), of about 1.2R(Q), with R(Q) = h/4e(2). However, in the presence of dc bias currents that are smaller than the zero-field critical currents, nuz becomes 0.75+/-0.10. This new set of exponents suggests that the field-tuned transitions with and without a dc bias current belong to different universality classes.

Energetics of eddy-mean flow interactions in the Brazil current between 20°S and 36°S

NASA Astrophysics Data System (ADS)

Magalhães, F. C.; Azevedo, J. L. L.; Oliveira, L. R.

2017-08-01

The energetics of eddy-mean flow interactions in the Brazil Current (BC) between 20°S and 36°S are investigated in 19 transects perpendicular to the 200 m isobath. Ten years (2000-2009) of output data from the Hybrid Coordinate Ocean Model (HYCOM) NCODA reanalysis, with a spatial resolution of 1/12.5° and 5 day averages, are used. The mean kinetic energy (MKE) and eddy kinetic energy (EKE) fields presented the same subsurface spatial pattern but with reduced values. The EKE increases southward, with high values along the BC path and the offshore portion of the jet. The values of the barotropic conversion term (BTC) are highest in the surface layers and decreased with depth, whereas the values of the baroclinic conversion term (BCC) and the vertical eddy heat flux (VEHF) are highest in the subsurface. Despite the vertical thickening of the BC, the highest energy conversion rates are confined to the upper 700 m of the water column. The energetic analysis showed that the current features mixed instability processes. The vertical weighted mean of the BTC and BCC presented an oscillatory pattern related to the bathymetry. The eddy field accelerates the time-mean flow upstream and downstream of bathymetric features and drains energy from the time-mean flow over the features. The BC is baroclinically unstable south of 28°S, and the highest energy conversion rates occur in Cabo de São Tomé, Cabo Frio, and the Cone do Rio Grande.

Predicting the Influence of Nano-Scale Material Structure on the In-Plane Buckling of Orthotropic Plates

NASA Technical Reports Server (NTRS)

Gates, Thomas S.; Odegard, Gregory M.; Nemeth, Michael P.; Frankland, Sarah-Jane V.

2004-01-01

A multi-scale analysis of the structural stability of a carbon nanotube-polymer composite material is developed. The influence of intrinsic molecular structure, such as nanotube length, volume fraction, orientation and chemical functionalization, is investigated by assessing the relative change in critical, in-plane buckling loads. The analysis method relies on elastic properties predicted using the hierarchical, constitutive equations developed from the equivalent-continuum modeling technique applied to the buckling analysis of an orthotropic plate. The results indicate that for the specific composite materials considered in this study, a composite with randomly orientated carbon nanotubes consistently provides the highest values of critical buckling load and that for low volume fraction composites, the non-functionalized nanotube material provides an increase in critical buckling stability with respect to the functionalized system.

False recognition production indexes in forward associative strength (FAS) lists with three critical words.

PubMed

Beato, María Soledad; Arndt, Jason

2014-01-01

False memory illusions have been widely studied using the Deese/Roediger-McDermott paradigm (DRM). In this paradigm, participants study words semantically related to a single nonpresented critical word. In a memory test critical words are often falsely recalled and recognized. The present study was conducted to measure the levels of false recognition for seventy-five Spanish DRM word lists that have multiple critical words per list. Lists included three critical words (e.g., HELL, LUCEFER, and SATAN) simultaneously associated with six studied words (e.g., devil, demon, fire, red, bad, and evil). Different levels of forward associative strength (FAS) between the critical words and their studied associates were used in the construction of the lists. Specifically, we selected lists with the highest FAS values possible and FAS was continuously decreased in order to obtain the 75 lists. Six words per list, simultaneously associated with three critical words, were sufficient to produce false recognition. Furthermore, there was wide variability in rates of false recognition (e.g., 53% for DUNGEON, PRISON, and GRATES; 1% for BRACKETS, GARMENT, and CLOTHING). Finally, there was no correlation between false recognition and associative strength. False recognition variability could not be attributed to differences in the forward associative strength.

Josephson current in ballistic graphene Corbino disk

NASA Astrophysics Data System (ADS)

Abdollahipour, Babak; Mohammadkhani, Ramin; Khalilzadeh, Mina

2018-06-01

We solve Dirac-Bogoliubov-De-Gennes (DBdG) equation in a superconductor-normal graphene-superconductor (SGS) junction with Corbino disk structure to investigate the Josephson current through this junction. We find that the critical current Ic has a nonzero value at Dirac point in which the concentration of the carriers is zero. We show this nonzero critical current depends on the system geometry and it decreases monotonically to zero by decreasing the ratio of the inner to outer radii of the Corbino disk (R1 /R2), while in the limit of R1 /R2 → 1 it scales like a diffusive Corbino disk. The product of the critical current and the normal-state resistance IcRN increases by increasing R1 /R2 and attains the same value for the wide and short rectangular structure at the limit of R1 /R2 → 1 at zero doping. These results reveals the pseudodiffusive behavior of the graphene Corbino Josephson junction similar to the rectangular structure at the zero doping.

High-Cost Patients: Hot-Spotters Don't Explain the Half of It.

PubMed

Lee, Natalie S; Whitman, Noah; Vakharia, Nirav; Taksler, Glen B; Rothberg, Michael B

2017-01-01

Understanding resource utilization patterns among high-cost patients may inform cost reduction strategies. To identify patterns of high-cost healthcare utilization and associated clinical diagnoses and to quantify the significance of hot-spotters among high-cost users. Retrospective analysis of high-cost patients in 2012 using data from electronic medical records, internal cost accounting, and the Centers for Medicare and Medicaid Services. K-medoids cluster analysis was performed on utilization measures of the highest-cost decile of patients. Clusters were compared using clinical diagnoses. We defined "hot-spotters" as those in the highest-cost decile with ≥4 hospitalizations or ED visits during the study period. A total of 14,855 Medicare Fee-for-service beneficiaries identified by the Medicare Quality Resource and Use Report as having received 100 % of inpatient care and ≥90 % of primary care services at Cleveland Clinic Health System (CCHS) in Northeast Ohio. The highest-cost decile was selected from this population. Healthcare utilization and diagnoses. The highest-cost decile of patients (n = 1486) accounted for 60 % of total costs. We identified five patient clusters: "Ambulatory," with 0 admissions; "Surgical," with a median of 2 surgeries; "Critically Ill," with a median of 4 ICU days; "Frequent Care," with a median of 2 admissions, 3 ED visits, and 29 outpatient visits; and "Mixed Utilization," with 1 median admission and 1 ED visit. Cancer diagnoses were prevalent in the Ambulatory group, care complications in the Surgical group, cardiac diseases in the Critically Ill group, and psychiatric disorders in the Frequent Care group. Most hot-spotters (55 %) were in the "frequent care" cluster. Overall, hot-spotters represented 9 % of the high-cost population and accounted for 19 % of their overall costs. High-cost patients are heterogeneous; most are not so-called "hot-spotters" with frequent admissions. Effective interventions to reduce costs will require a more multi-faceted approach to the high-cost population.

Consensus recommendations for the management of hyperglycaemia in critically ill patients in the Indian setting.

PubMed

Mukherjee, J J; Chatterjee, P S; Saikia, M; Muruganathan, A; Das, Ashok Kumar

2014-07-01

Hyperglycaemia occurs frequently in critically-ill patients. Not only does it occur among patients with pre-existing diabetes mellitus but elevated blood glucose values during an acute illness can also be seen in previously glucose-tolerant individuals (stress hyperglycaemia). Numerous observational studies have shown an increase in morbidity and mortality in critically ill patients with hyperglycaemia. Interestingly, outcomes in individuals with stress hyperglycaemia are worse than that in critically ill hyperglycaemic patients with pre-existing diabetes. Proper management of hyperglycaemia has been shown to result in improved clinical outcomes. Critically ill patients with hyperglycaemia should primarily be managed with intravenous insulin infusion to allow dynamic adjustment of treatment to suit the rapid changes in blood glucose values in these patients. Currently, there are in existence a fair number of published protocols to administer intensive intravenous insulin therapy that range from the relatively simple to the fairly complex. Different management strategies have been proposed depending upon whether the critically ill hyperglycaemic patient is stationed in the emergency department, the medical intensive care unit (ICU), the surgical ICU or the coronary care unit. Moreover, the ideal target blood glucose value to maintain in this group of patients remains controversial. Keeping these issues in mind, a group of leading experts in the fields of diabetes and critical care extensively reviewed the literature and framed recommendations with special attention to clinical practice in India. The aim was to formulate recommendations which are based on sound evidence and yet are simple and easy to understand and implement across the ICU throughout the country. In the current recommendations, intensive intravenous insulin therapy has been suggested as the preferred mode of managing hyperglycaemia in patients admitted to critical care settings. The current recommendations suggest using a simple and similar protocol for managing hyperglycaemia in critically-ill patients irrespective of their location among the various critical care units in a hospital. Recommendations have also been made for transition from intravenous to subcutaneous administration of insulin when the patient is transferred out of the critical care setting. It is hoped that the current recommendations shall form the basis for the management of hyperglycaemia in critically ill patients across the country.

Following Alice: Theories of Critical Thinking and Reflective Practice in Action at Postgraduate Level

ERIC Educational Resources Information Center

Swanwick, Ruth; Kitchen, Ruth; Jarvis, Joy; McCracken, Wendy; O'Neil, Rachel; Powers, Steve

2014-01-01

This paper presents a flexible framework of principles for teaching critical thinking and reflective practice skills at the postgraduate level. It reports on a collaborative project between four UK institutions providing postgraduate programmes in deaf education. Through a critical review of current theories of critical thinking and reflective…

Irradiation response of commercial, high-Tc superconducting tapes: Electromagnetic transport properties

DOE PAGES

Gapud, A. A.; Greenwood, N. T.; Alexander, J. A.; ...

2015-07-01

Effects of low dose irradiation on the electrical transport current properties of commercially available high-temperature superconducting, coated-conductor tapes were investigated, in view of potential applications in the irradiative environment of fusion reactors. Three different tapes, each with unique as-grown flux-pinning structures, were irradiated with Au and Ni ions at energies that provide a range of damage effects, with accumulated damage levels near that expected for conductors in a fusion reactor environment. Measurements using transport current determined the pre- and post-irradiation resistivity, critical current density, and pinning force density, yielding critical temperatures, irreversibility lines, and inferred vortex creep rates. Results showmore » that at the irradiation damage levels tested, any detriment to as-grown pre-irradiation properties is modest; indeed in one case already-superior pinning forces are enhanced, leading to higher critical currents.« less

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

Rupich, Martin W.; Sathyamurthy, Srivatsan; Fleshler, Steven

We demonstrate a twofold increase in the in-field critical current of AMSC's standard 2G coil wire by irradiation with 18-MeV Au ions. The optimum pinning enhancement is achieved with a dose of 6 × 10 11 Au ions/cm 2. Although the 77 K, self-field critical current is reduced by about 35%, the in-field critical current (H//c) shows a significant enhancement between 4 and 50 K in fields > 1 T. The process was used for the roll-to-roll irradiation of AMSC's standard 46-mm-wide production coated conductor strips, which were further processed into standard copper laminated coil wire. The long-length wires showmore » the same enhancement as attained with short static irradiated samples. The roll-to-roll irradiation process can be incorporated in the standard 2G wire manufacturing, with no modifications to the current process. In conclusion, the enhanced performance of the wire will benefit rotating machine and magnet applications.« less

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

Rupich, Martin W.; Sathyamurthy, Srivatsan; Fleshler, Steven

We demonstrate a twofold increase in the in-field critical current of AMSC's standard 2G coil wire by irradiation with 18-MeV Au ions. The optimum pinning enhancement is achieved with a dose of 6 x 10(11) Au ions/cm(2). Although the 77 K, self-field critical current is reduced by about 35%, the in-field critical current (H//c) shows a significant enhancement between 4 and 50 K in fields > 1 T. The process was used for the roll-to-roll irradiation of AMSC's standard 46-mm-wide production coated conductor strips, which were further processed into standard copper laminated coil wire. The long-length wires show the samemore » enhancement as attained with short static irradiated samples. The roll-to-roll irradiation process can be incorporated in the standard 2G wire manufacturing, with no modifications to the current process. The enhanced performance of the wire will benefit rotating machine and magnet applications.« less

Comment on ''Carrier-concentration dependence of critical superconducting current induced by the proximity effect in silicon''

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

Kleinsasser, A.W.

1987-06-01

It is pointed out that effect of an applied gate voltage on the critical current observed in a gate-controlled Si-coupled weak link by Nishino, Yamada, and Kawabe (Phy. Rev. B 33, 2042 (1986)) is much larger than that expected from the small change of carrier density in the link.

Apparatus for measurement of critical current in superconductive tapes

DOEpatents

Coulter, J. Yates; DePaula, Raymond

2002-01-01

A cryogenic linear positioner which is primarily used for characterizing coated conductor critical current homogeneity at 75K is disclosed. Additionally, this tool can be used to measure the positional dependence of the coated conductor resistance at room temperature, and the room temperature resistance of the underlying YBCB coating without the overlaying protective cover of silver.

Noncontact Measurement Of Critical Current In Superconductor

NASA Technical Reports Server (NTRS)

Israelsson, Ulf E.; Strayer, Donald M.

1992-01-01

Critical current measured indirectly via flux-compression technique. Magnetic flux compressed into gap between superconductive hollow cylinder and superconductive rod when rod inserted in hole in cylinder. Hall-effect probe measures flux density before and after compression. Method does not involve any electrical contact with superconductor. Therefore, does not cause resistive heating and consequent premature loss of superconductivity.

A Critical Analysis of Approaches To Targeted PTSD Prevention: Current Status and Theoretically Derived Future Directions

ERIC Educational Resources Information Center

Feldner, Matthew T.; Monson, Candice M.; Friedman, Matthew J.

2007-01-01

Although efforts to prevent posttraumatic stress disorder (PTSD) have met with relatively limited success, theoretically driven preventive approaches with promising efficacy are emerging. The current article critically reviews investigations of PTSD prevention programs that target persons at risk for being exposed to a traumatic event or who have…

Critical Issues for Teacher Educators and Literacy Specialists: A View from Higher Education in New York

ERIC Educational Resources Information Center

Goatley, Virginia

2008-01-01

This article outlines five critical issues for teacher educators and literacy specialists in New York State. Intended to raise issues and share recent policy decisions, the article provides background and conversations about current policy. Readers are encouraged to make decisions about how to participate in the current conversations across the…

National facilities study. Volume 2: Task group on aeronautical research and development facilities report

NASA Technical Reports Server (NTRS)

1994-01-01

The Task Group on Aeronautics R&D Facilities examined the status and requirements for aeronautics facilities against the competitive need. Emphasis was placed on ground-based facilities for subsonic, supersonic and hypersonic aerodynamics, and propulsion. Subsonic and transonic wind tunnels were judged to be most critical and of highest priority. Results of the study are presented.

Ashwagandha supplementation enhances ovarian tumoricidal activity of NK cells | Division of Cancer Prevention

Cancer.gov

Ovarian cancer (OVCA) is a fatal malignancy of women with highest case to death ratio among gynecological cancers. OVCA differs from other malignancies that it mainly disseminates locally in the peritoneal and abdominal cavity. Thus, factors in tumor microenvironment play critical roles in tumor progression as well as prevention of OVCA metastasis. Innate immune cells are

"Just Let the Worst Students Go": A Critical Case Analysis of Public Discourse about Race, Merit, and Worth

ERIC Educational Resources Information Center

Zirkel, Sabrina; Pollack, Terry M.

2016-01-01

We present a case analysis of the controversy and public debate generated from a school district's efforts to address racial inequities in educational outcomes by diverting special funds from the highest performing students seeking elite college admissions to the lowest performing students who were struggling to graduate from high school.…

Vision science literature of Nepal in the database "Web of Science".

PubMed

Risal, S; Prasad, H N

2012-01-01

Vision Science is considered to be a quite developed discipline in Nepal, with much research currently in progress. Though the results of these endeavors are published in scientific journals, formal citation analyses have not been performed on works contributed by Nepalese vision scientists. To study Nepal's contribution to vision science literature in the database "Web of Science". The primary data source of this paper was Web of Science, a citation database of Thomas Reuters. All bibliometric analyses were performed with the help of Web of Science analysis service. In the current database of vision science literature, Nepalese authors contributed 112 publications to Web of Science, 95 of which were original articles. Pokharel GP had the highest number of citations among contributing authors of Nepal. Hennig A contributed the highest number of article as a first author. The Nepal Eye Hospital contributed the highest number of articles as an institution to the field of Vision Science. Currently, only two journals from Nepal including Journal of Nepal Medical Association (JAMA) are indexed in the Web of Science database (Sieving, 2012). To evaluate the total productivity of vision science literature from Nepal, total publication counts from national journals and articles indexed in other databases such as PubMed and Scopus must also be considered. © NEPjOPH.

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

Field, Kevin G.; Briggs, Samuel A.; Sridharan, Kumar

The development and understanding of the mechanical properties of neutron-irradiated FeCrAl alloys is increasingly a critical need as these alloys continue to become more mature for nuclear reactor applications. This study focuses on the mechanical properties of model FeCrAl alloys and of a commercial FeCrAl alloy neutron-irradiated to up to 13.8 displacements per atom (dpa) at irradiation temperatures between 320 and 382 °C. Tensile tests were completed at room temperature and at 320 °C, and a subset of fractured tensile specimens was examined by scanning electron microscopy. Results showed typical radiation hardening and embrittlement indicative of high chromium ferritic alloysmore » with strong chromium composition dependencies at lower doses. At and above 7.0 dpa, the mechanical properties saturated for both the commercial and model FeCrAl alloys, although brittle cleavage fracture was observed at the highest dose in the model FeCrAl alloy with the highest chromium content (18 wt %). Finally, the results suggest the composition and microstructure of FeCrAl alloys plays a critical role in the mechanical response of FeCrAl alloys irradiated near temperatures relevant to light water reactors.« less

Mechanical properties of neutron-irradiated model and commercial FeCrAl alloys

DOE PAGES

Field, Kevin G.; Briggs, Samuel A.; Sridharan, Kumar; ...

2017-03-28

The development and understanding of the mechanical properties of neutron-irradiated FeCrAl alloys is increasingly a critical need as these alloys continue to become more mature for nuclear reactor applications. This study focuses on the mechanical properties of model FeCrAl alloys and of a commercial FeCrAl alloy neutron-irradiated to up to 13.8 displacements per atom (dpa) at irradiation temperatures between 320 and 382 °C. Tensile tests were completed at room temperature and at 320 °C, and a subset of fractured tensile specimens was examined by scanning electron microscopy. Results showed typical radiation hardening and embrittlement indicative of high chromium ferritic alloysmore » with strong chromium composition dependencies at lower doses. At and above 7.0 dpa, the mechanical properties saturated for both the commercial and model FeCrAl alloys, although brittle cleavage fracture was observed at the highest dose in the model FeCrAl alloy with the highest chromium content (18 wt %). Finally, the results suggest the composition and microstructure of FeCrAl alloys plays a critical role in the mechanical response of FeCrAl alloys irradiated near temperatures relevant to light water reactors.« less

Mechanical properties of neutron-irradiated model and commercial FeCrAl alloys

NASA Astrophysics Data System (ADS)

Field, Kevin G.; Briggs, Samuel A.; Sridharan, Kumar; Howard, Richard H.; Yamamoto, Yukinori

2017-06-01

The development and understanding of the mechanical properties of neutron-irradiated FeCrAl alloys is increasingly a critical need as these alloys continue to become more mature for nuclear reactor applications. This study focuses on the mechanical properties of model FeCrAl alloys and of a commercial FeCrAl alloy neutron-irradiated to up to 13.8 displacements per atom (dpa) at irradiation temperatures between 320 and 382 °C. Tensile tests were completed at room temperature and at 320 °C, and a subset of fractured tensile specimens was examined by scanning electron microscopy. Results showed typical radiation hardening and embrittlement indicative of high chromium ferritic alloys with strong chromium composition dependencies at lower doses. At and above 7.0 dpa, the mechanical properties saturated for both the commercial and model FeCrAl alloys, although brittle cleavage fracture was observed at the highest dose in the model FeCrAl alloy with the highest chromium content (18 wt %). The results suggest the composition and microstructure of FeCrAl alloys plays a critical role in the mechanical response of FeCrAl alloys irradiated near temperatures relevant to light water reactors.

A 10 Kelvin 3 Tesla Magnet for Space Flight ADR Systems

NASA Technical Reports Server (NTRS)

Tuttle, Jim; Shirron, Peter; Canavan, Edgar; DiPirro, Michael; Riall, Sara; Pourrahimi, Shahin

2003-01-01

Many future space flight missions are expected to use adiabatic demagnetization refrigerators (ADRs) to reach detector operating temperatures well below one Kelvin. The goal is to operate each ADR with a mechanical cooler as its heat sink, thus avoiding the use of liquid cryogens. Although mechanical coolers are being developed to operate at temperatures of 6 Kelvin and below, there is a large efficiency cost associated with operating them at the bottom of their temperature range. For the multi-stage ADR system being developed at Goddard Space Flight Center, the goal is to operate with a 10 Kelvin mechanical cooler heat sink. With currently available paramagnetic materials, the highest temperature ADR stage in such a system will require a magnetic field of approximately three Tesla. Thus the goal is to develop a small, lightweight three Tesla superconducting magnet for operation at 10 Kelvin. It is important that this magnet have a low current/field ratio. Because traditional NbTi magnets do not operate safely above about six Kelvin, a magnet with a higher Tc is required. The primary focus has been on Nb3Sn magnets. Since standard Nb3Sn wire must be coated with thick insulation, wound on a magnet mandrel and then reacted, standard Nb,Sn magnets are quite heavy and require high currents Superconducting Systems developed a Nb3Sn wire which can be drawn down to small diameter, reacted, coated with thin insulation and then wound on a small diameter coil form. By using this smaller wire and operating closer to the wire s critical current, it should be possible to reduce the mass and operating current of 10 Kelvin magnets. Using this "react-then-wind" technology, Superconducting Systems has produced prototype 10 Kelvin magnets. This paper describes the development and testing of these magnets and discusses the outlook for including 10 Kelvin magnets on space-flight missions.

Critical swimming speed of brown trout (Salmo trutta) infested with freshwater pearl mussel (Margaritifera margaritifera) glochidia and implications for artificial breeding of an endangered mussel species.

PubMed

Taeubert, Jens-Eike; Geist, Juergen

2013-04-01

Unionid freshwater mussels need to attach to a host fish for completion of their life cycle. It remains unclear whether the relationship between these mussels and their host fishes can be considered parasitic, mutualistic, or commensal. Herein, we studied the effects of Margaritifera margaritifera infestation on Salmo trutta, the most important host of this endangered mussel species in Central Europe. Glochidial load of host fish increased with increasing glochidial concentration, but the highest ratios of encysted glochidia to exposed glochidia were found at low concentration (15,000 glochidia L(-1)) during infestation. Host fish mortality occurred at infestation rates of ~350 glochidia per g fish weight and was highest (60%) at the highest infestation rates (~900 glochidia per g fish weight). On a sublethal level, swimming performance of hosts was inversely related to infestation rates, with infestation of ~900 glochidia per g fish weight reducing critical swimming speed of S. trutta significantly by ~20% compared to infestation with 6 glochidia per g fish weight. The high mortality and the impaired swimming capability of highly infested hosts indicate a parasitic interaction between M. margaritifera and its host. For conservation and reintroduction of M. margaritifera via glochidia-infested S. trutta, we recommend glochidial loads of 5-100 glochidia per g fish weight, while for artificial breeding of juvenile M. margaritifera under laboratory conditions, higher infestation rates of up to 300 glochidia per g fish weight are ideal to balance high yields of mussels and welfare of host fishes.

Integrated Real-Time Control and Imaging System for Microbiorobotics and Nanobiostructures

DTIC Science & Technology

2016-01-11

kit with a control board and ALP 4.1 basic controller suite. The digital micromirror device is the highest resolution 16:9 aspect ratio system. This...in Figure 1, consisted of the following: (1) digital micromirror device (DMD) and controller, (2) an inverted epifluorescence microscope with a flat...accompanying control board and ALP 4.1 basic controller suite. The digital micromirror device is currently the highest commercially available

Worldwide prevalence and incidence of osteoporotic vertebral fractures.

PubMed

Ballane, G; Cauley, J A; Luckey, M M; El-Hajj Fuleihan, G

2017-05-01

We investigated the prevalence and incidence of vertebral fractures worldwide. We used a systematic Medline search current to 2015 and updated as per authors' libraries. A total of 62 articles of fair to good quality and comparable methods for vertebral fracture identification were considered. The prevalence of morphometric vertebral fractures in European women is highest in Scandinavia (26%) and lowest in Eastern Europe (18%). Prevalence rates in North America (NA) for White women ≥50 are 20-24%, with a White/Black ratio of 1.6. Rates in women ≥50 years in Latin America are overall lower than Europe and NA (11-19%). In Asia, rates in women above ≥65 are highest in Japan (24%), lowest in Indonesia (9%), and in the Middle East, Lebanon, rates are 20%. The highest-lowest ratio between countries, within and across continents, varied from 1.4-2.6. Incidence data is less abundant and more heterogeneous. Age-standardized rates in studies combining hospitalized and ambulatory vertebral fractures are highest in South Korea, USA, and Hong Kong and lowest in the UK. Neither a North-South gradient nor a relation to urbanization is evident. Conversely, the incidence of hospitalized vertebral fractures in European patients ≥50 shows a North-South gradient with 3-3.7-fold variability. In the USA, rates in Whites are approximately 4-fold higher than in Blacks. Vertebral fractures variation worldwide is lower than observed with hip fractures, and some of highest rates are unexpectedly from Asia. Better quality representative studies are needed. We investigate the occurrence of vertebral fractures, worldwide, using published data current until the present. Worldwide, the variation in vertebral fractures is lower than observed for hip fractures. Some of the highest rates are from North America and unexpectedly Asia. The highest-lowest ratio between countries, within and across continents, varied from 1.4-2.6. Better quality representative data is needed.

Dark Zones of Solid Propellant Flames: Critical Assessment and Quantitative Modeling of Experimental Datasets With Analysis of Chemical Pathways and Sensitivities

DTIC Science & Technology

2011-01-01

with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1...Research Associate at ARL with WRA, and largely completed more recently while at Dept. of Chem., SUNY, Cortland, NY. Currently unaffiliated. †Former...promised to provide an extensive, definitive review critically assessing our current understanding of DZ structure and chemistry, and providing a documented

Kinetics of Electrocatalytic Reactions from First-Principles: A Critical Comparison with the Ab Initio Thermodynamics Approach.

PubMed

Exner, Kai S; Over, Herbert

2017-05-16

Multielectron processes in electrochemistry require the stabilization of reaction intermediates (RI) at the electrode surface after every elementary reaction step. Accordingly, the bond strengths of these intermediates are important for assessing the catalytic performance of an electrode material. Current understanding of microscopic processes in modern electrocatalysis research is largely driven by theory, mostly based on ab initio thermodynamics considerations, where stable reaction intermediates at the electrode surface are identified, while the actual free energy barriers (or activation barriers) are ignored. This simple approach is popular in electrochemistry in that the researcher has a simple tool at hand in successfully searching for promising electrode materials. The ab initio TD approach allows for a rough but fast screening of the parameter space with low computational cost. However, ab initio thermodynamics is also frequently employed (often, even based on a single binding energy only) to comprehend on the activity and on the mechanism of an electrochemical reaction. The basic idea is that the activation barrier of an endergonic reaction step consists of a thermodynamic part and an additional kinetically determined barrier. Assuming that the activation barrier scales with thermodynamics (so-called Brønsted-Polanyi-Evans (BEP) relation) and the kinetic part of the barrier is small, ab initio thermodynamics may provide molecular insights into the electrochemical reaction kinetics. However, for many electrocatalytic reactions, these tacit assumptions are violated so that ab initio thermodynamics will lead to contradictions with both experimental data and ab initio kinetics. In this Account, we will discuss several electrochemical key reactions, including chlorine evolution (CER), oxygen evolution reaction (OER), and oxygen reduction (ORR), where ab initio kinetics data are available in order to critically compare the results with those derived from a simple ab initio thermodynamics treatment. We show that ab initio thermodynamics leads to erroneous conclusions about kinetic and mechanistic aspects for the CER over RuO 2 (110), while the kinetics of the OER over RuO 2 (110) and ORR over Pt(111) are reasonably well described. Microkinetics of an electrocatalyzed reaction is largely simplified by the quasi-equilibria of the RI preceding the rate-determining step (rds) with the reactants. Therefore, in ab initio kinetics the rate of an electrocatalyzed reaction is governed by the transition state (TS) with the highest free energy G rds # , defining also the rate-determining step (rds). Ab initio thermodynamics may be even more powerful, when using the highest free energy of an reaction intermediate G max (RI) rather than the highest free energy difference between consecutive reaction intermediates, ΔG loss , as a descriptor for the kinetics.

Nonstoichiometric Solution-Processed BaTiO₃ Film for Gate Insulator Applications.

PubMed

Lau, Joyce; Kim, Sangsub; Kim, Hyunki; Koo, Kwangjun; Lee, Jaeseob; Kim, Sangsoo; Choi, Byoungdeog

2018-09-01

Solution processed barium titanate (BTO) was used to fabricate an Al/BaTiO3/p-Si metal-insulator-semiconductor (MIS) structure, which was used as a gate insulator. Changes in the electrical characteristics of the film were investigated as a function of the film thickness and post deposition annealing conditions. Our results showed that a thickness of 5 layers and an annealing temperature of 650 °C produced the highest electrical performance. BaxTi1-xO3 was altered at x = 0.10, 0.30, 0.50, 0.70, 0.90, and 1.0 to investigate changes in the electrical properties as a function of composition. The highest dielectric constant of 87 was obtained for x = 0.10, while the leakage current density was suppressed as Ba content increased. The lowest leakage current density was 1.34×10-10 A/cm2, which was observed at x = 0.90. The leakage current was related to the resistivity of the film, the interface states, and grain densification. Space charge limited current (SCLC) was the dominant leakage mechanism in BTO films based on leakage current analysis. Although a Ba content of x = 0.90 had the highest trap density, the traps were mainly composed of Ti-vacancies, which acted as strong electron traps and affected the film resistivity. A secondary phase, Ba2TiO4, which was observed in cases of excess Ba, acted as a grain refiner and provided faster densification of the film during the thermal process. The absence of a secondary phase in BaO (x = 1.0) led to the formation of many interface states and degradation in the electrical properties. Overall, the insulator properties of BTO were improved when the composition ratio was x = 0.90.

Lifecourse educational status in relation to weight gain in African American women

PubMed Central

Coogan, Patricia F.; Wise, Lauren A.; Cozier, Yvette C.; Palmer, Julie R.; Rosenberg, Lynn

2013-01-01

Objectives Childhood disadvantage has been associated with increased risk of obesity from childhood through adulthood and those who are disadvantaged across the lifecourse are at highest risk. The effect of lifecourse socioeconomic status (SES) is particularly important for black women due to the higher prevalence of low SES and obesity in black compared to white women. We assessed associations of lifecourse SES, as indicated by educational status, with adult weight in African American women. Design We assessed the associations of parental education, current education (education of participant or her spouse), and a combination of parental and current education (lifecourse education) with weight gain among 21,457 women aged less than age 55 in the longitudinal Black Women’s Health Study which began in 1995. Main Outcome Measures We estimated the mean difference in weight gain between age 18 and age in 2009, and risk ratios for obesity in 2009, in each level of education compared to the highest level (college graduate). Results The age- and height-adjusted differences in mean weight gain for the lowest levels of parental and current education compared to the highest levels were 3.29 and 4.49 kg, respectively. The age-adjusted risk ratios for obesity for the lowest level of parental and current education were 1.44 (95% CI 1.32-1.57) and 1.75 (95% CI 1.57-1.95), respectively. Risk of obesity for was lowest among those with current education of college graduate, regardless of parental education. Conclusions Educational level of college graduate may overcome the adverse effects of low parental education on weight gain and obesity risk. PMID:22764643

Critical current enhancement in large grains of YBa(2)Cu(3)O(7-delta) through microstructural engineering

NASA Astrophysics Data System (ADS)

Chopra, Manoj

High temperature superconductors (HTS) have many potential applications e.g. magnetically levitated trains, power transmission, mechanical energy storage, dent pullers, Nuclear Magnetic Resonance (N.M.R), magnetic resonance imaging (M.R.I) etc. However, one of the most daunting tasks for the applicability of HTS is the enhancement of critical current density (Jc) and flux-pinning at liquid nitrogen temperatures by microstructure design. The addition of Ysb2BaCuOsb5 (211) particles to large grain melt textured YBasb2Cusb3Osb{7-delta} (Y123) have significantly improved the transport and magnetic properties of this material. Here, a systematic quantitative analysis on the effects of the 211 addition was performed on a microscopic scale with a systematic variation in the initial volume percentage of 211. From the correlation between critical current measurements and quantitative microscopy of both (001) and (110) sections, a maximum value of Jc was observed corresponding to a measured Y123 volume percent of 20% ± 3%. Accounting for the loss of liquid phase for the present processing, the corresponding optimum initial volume of 211 for the highest measured Jc was 40%. Further comparison between the weighted Jc and the true flux pinning force (Fp) also showed a maximum pinning force for an initial 211 addition of 40%. Although, the weighted Jc starts to decrease with an initial 211 volume of above 40%, the pinning efficiency at higher magnetic fields (2-4T) of the superconducting Y123 matrix was actually improved with an increasing 211 addition to at least 50%. Though an increasing addition of 211 was effective in producing efficient flux pinning sites in the Y123 matrix, percolation paths in the Y123 matrix became limited for supercurrent flow. Hence, a measured 211 volume corresponding to 80% 211 was shown to have the best possible critical current density. Furthermore, crack opening and crack spacing of the superficial cracks were found to decrease with an increasing 211 addition and with a decreasing 211 interparticle spacing. The penetration and surface length of each of these superficial cracks were hence reduced, which led to better electrical connectivity in the Y123 matrix. In addition, the effect of additives such as platinum and cerium oxide and their effect on the defect microstructure was quantitatively determined. Average twin spacing observed experimentally, suggested that the twin boundary energy (gammasb{tw}) was 28.9mJ/msp2 normally, while it decreased to 11.35mJ/msp2 for the 0.5wt% PtOsb2 doping and 23.6 mJ/msp2 for the case of 1 wt% CeOsb2 addition. The resultant twin morphology was also found to be substantially finer with PtOsb2 doping. Twin boundary energies were independently determined from twin shape analysis. Closer observation of the twins around a 211/Y123 interface showed a {1/ Rsp2} functional dependence of the local twin spacing at the 211/Y123 interface. The present study has also led to the identification of certain novel twin structures that have been shown to he efficient flux pinning sites. A study of this structure and its relationship with 211 particle shape, dispersion and proximity to its neighbors and its consequent effect on flux pinning was shown.

Analysis and critical assessment of the current and near future plans of the Brazilian satellite applications program and its role in the global space program

NASA Technical Reports Server (NTRS)

Parada, N. D. J. (Principal Investigator)

1983-01-01

Brazilian programs using satellites for remote sensing, meteorology and communications are analyzed including their current status and near future plans. The experience gained and available information are used to critically discuss some aspects of great importance for the existing and prospective user countries.

Critical current oscillations of elliptical Josephson junctions with single-domain ferromagnetic layers

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

Glick, Joseph A.; Khasawneh, Mazin A.; Niedzielski, Bethany M.

We report that josephson junctions containing ferromagnetic layers are of considerable interest for the development of practical cryogenic memory and superconducting qubits. Such junctions exhibit a ground-state phase shift of π for certain ranges of ferromagnetic layer thicknesses. We present studies of Nb based micron-scale elliptically shaped Josephson junctions containing ferromagnetic barriers of Ni 81Fe 19 or Ni 65Fe 15Co 20. By applying an external magnetic field, the critical current of the junctions is found to follow characteristic Fraunhofer patterns and display sharp switching behavior suggestive of single-domain magnets. The high quality of the Fraunhofer patterns enables us to extractmore » the maximum value of the critical current even when the peak is shifted significantly outside the range of the data due to the magnetic moment of the ferromagnetic layer. The maximum value of the critical current oscillates as a function of the ferromagnetic barrier thickness, indicating transitions in the phase difference across the junction between values of zero and π. Lastly, we compare the data to previous work and to models of the 0-π transitions based on existing theories.« less

Critical current oscillations of elliptical Josephson junctions with single-domain ferromagnetic layers

DOE PAGES

Glick, Joseph A.; Khasawneh, Mazin A.; Niedzielski, Bethany M.; ...

2017-10-06

We report that josephson junctions containing ferromagnetic layers are of considerable interest for the development of practical cryogenic memory and superconducting qubits. Such junctions exhibit a ground-state phase shift of π for certain ranges of ferromagnetic layer thicknesses. We present studies of Nb based micron-scale elliptically shaped Josephson junctions containing ferromagnetic barriers of Ni 81Fe 19 or Ni 65Fe 15Co 20. By applying an external magnetic field, the critical current of the junctions is found to follow characteristic Fraunhofer patterns and display sharp switching behavior suggestive of single-domain magnets. The high quality of the Fraunhofer patterns enables us to extractmore » the maximum value of the critical current even when the peak is shifted significantly outside the range of the data due to the magnetic moment of the ferromagnetic layer. The maximum value of the critical current oscillates as a function of the ferromagnetic barrier thickness, indicating transitions in the phase difference across the junction between values of zero and π. Lastly, we compare the data to previous work and to models of the 0-π transitions based on existing theories.« less

Critical current density of TlBa 2Ca 2Cu 3O 9 thin films on MgO (100) in magnetic fields

NASA Astrophysics Data System (ADS)

Piehler, A.; Ströbel, J. P.; Reschauer, N.; Löw, R.; Schönberger, R.; Renk, K. F.; Kraus, M.; Daniel, J.; Saemann-Ischenko, G.

1994-04-01

We report on the critical current density of TlBa 2Ca 2Cu 3O 9 thin films on (100) MgO substrates in magnetic fields. Single- phase and highly c-axis oriented thin films were prepared by laser ablation in combination with thermal evaporation of Tl 2O 3. Scanning electron microscope investigations indicated a flat plate-like microstructure and DC magnetization measurements showed the onset of superconductivity at ∼ 115 K. The critical current density jc was determined from magnetization cycles. Typical values of jc were 9 × 10 5 A/cm 2 at 6 K and 2.5 × 10 5 A/cm 2 at 77 K. In a magnetic field to 1 T applied parallel to the c-axis the critical current densities were 3 × 10 5 A/cm 2 at 6 K and 3 × 10 3 A/cm 2 at 77 K. The decrease of jc at higher magnetic fields is discussed and attributed to the microstructure of the TlBa 2Ca 2Cu 3O 9 thin films.

Training dedicated emergency physicians in surgical critical care: knowledge acquisition and workforce collaboration for the care of critically ill trauma/surgical patients.

PubMed

Chiu, William C; Marcolini, Evie G; Simmons, Dell E; Yeatts, Dale J; Scalea, Thomas M

2011-07-01

The Leapfrog Group initiative has led to an increasing public demand for dedicated intensivists providing critical care services. The Acute Care Surgery training initiative promotes an expansion of trauma/surgical care and operative domain, redirecting some of our focus from critical care. Will we be able to train and enforce enough intensivists to care for critically ill surgical patients? We have been training emergency physicians (EPs) alongside surgeons in our country's largest Trauma/Surgical Critical Care Fellowship Program annually for more than a decade. We reviewed our Society of Critical Care Medicine Multidisciplinary Critical Care Knowledge Assessment Program (MCCKAP, critical care in-training examination) scores from 2006 to 2009 (4 years). The MCCKAP, administered during the ninth month of a Critical Care Fellowship, is the only known standardized objective examination available in this country to compare critical care knowledge acquisition across different specialties. Subsequent workforce outcome for these Emergency Medicine Critical Care Fellowship graduates was analyzed. Over the 4-year period, we trained 42 Fellows in our Program who qualified for this study (30 surgeons and 12 EPs). Surgeons and EP performance scores on the MCCKAP examination were not different. The mean National Board Equivalent score was 419 ± 61 (mean ± standard deviation) for surgeons and 489 ± 87 for EPs. The highest score was achieved by an EP. The lowest score was not achieved by an EP. Ten of 12 (83%) EP Critical Care Fellowship graduates are practicing inpatient critical care in intensive care units with attending physician level responsibilities. EPs training in a Surgical Critical Care Fellowship can acquire critical care knowledge equivalent to that of surgeons. EPs trained in a Surgical Critical Care paradigm can potentially expand the intensive care unit workforce for Surgical Critical Care patients.

Advanced cogeneration research study: Executive summary

NASA Technical Reports Server (NTRS)

Bluhm, S. A.; Moore, N.; Rosenberg, L.; Slonski, M.

1983-01-01

This study provides a broad based overview of selected areas relevant to the development of a comprehensive Southern California Edison (SCE) advanced cogeneration project. The areas studied are: (1) Cogeneration potential in the SCE service territory; (2) Advanced cogeneration technologies; and (3) Existing cogeneration computer models. An estimated 3700 MW sub E could potentially be generated from existing industries in the Southern California Edison service territory using cogeneration technology. Of this total, current technology could provide 2600 MW sub E and advanced technology could provide 1100 MW sub E. The manufacturing sector (SIC Codes 20-39) was found to have the highest average potential for current cogeneration technology. The mining sector (SIC Codes 10-14) was found to have the highest potential for advanced technology.

Hawking radiation and nonequilibrium quantum critical current noise.

PubMed

Sonner, Julian; Green, A G

2012-08-31

The dynamical scaling of quantum critical systems in thermal equilibrium may be inherited in the driven steady state, leading to universal out-of-equilibrium behavior. This attractive notion has been demonstrated in just a few cases. We demonstrate how holography-a mapping between the quantum critical system and a gravity dual-provides an illuminating perspective and new results. Nontrivial out-of-equilibrium universality is particularly apparent in current noise, which is dual to Hawking radiation in the gravitational system. We calculate this in a two-dimensional system driven by a strong in-plane electric field and deduce a universal scaling function interpolating between previously established equilibrium and far-from-equilibrium current noise. Since this applies at all fields, out-of-equilibrium experiments no longer require very high fields for comparison with theory.

Structural and critical current properties in Al-doped MgB 2

NASA Astrophysics Data System (ADS)

Zheng, D. N.; Xiang, J. Y.; Lang, P. L.; Li, J. Q.; Che, G. C.; Zhao, Z. W.; Wen, H. H.; Tian, H. Y.; Ni, Y. M.; Zhao, Z. X.

2004-08-01

A series of Al-doped Mg 1- xAl xB 2 samples have been fabricated and systematic study on structure and superconducting properties have been carried out for the samples. In addition to a structural transition observed by XRD, TEM micrographs showed the existence of a superstructure of double c-axis lattice constant along the direction perpendicular to the boron honeycomb sheet. In order to investigate the effect of Al doping on flux pinning and critical current properties in MgB 2, measurements on the superconducting transition temperature Tc, irreversible field Birr and critical current density Jc were performed too, for the samples with the doping levels lower than 0.15 in particular. These experimental observations were discussed in terms of Al doping induced changes in carrier concentration.

Qualitative Analysis of Written Reflections during a Teaching Certificate Program

PubMed Central

Castleberry, Ashley N.; Payakachat, Nalin; Ashby, Sarah; Nolen, Amanda; Carle, Martha; Neill, Kathryn K.

2016-01-01

Objective. To evaluate the success of a teaching certificate program by qualitatively evaluating the content and extent of participants’ reflections. Methods. Two investigators independently identified themes within midpoint and final reflection essays across six program years. Each essay was evaluated to determine the extent of reflection in prompted teaching-related topic areas (strengths, weaknesses, assessment, feedback). Results. Twenty-eight themes were identified within 132 essays. Common themes encompassed content delivery, student assessment, personal successes, and challenges encountered. Deep reflection was exhibited, with 48% of essays achieving the highest level of critical reflection. Extent of reflection trended higher from midpoint to final essays, with significant increases in the strengths and feedback areas. Conclusion. The teaching certificate program fostered critical reflection and self-reported positive behavior change in teaching, thus providing a high-quality professional development opportunity. Such programs should strongly consider emphasizing critical reflection through required reflective exercises at multiple points within program curricula. PMID:26941436

Effect of notch depth of modified current collector on internal-short-circuit mitigation for lithium-ion battery

NASA Astrophysics Data System (ADS)

Wang, Meng; Noelle, Daniel J.; Shi, Yang; Le, Anh V.; Qiao, Yu

2018-01-01

Formation of internal short circuit (ISC) may result in catastrophic thermal runaway of lithium-ion battery (LIB). Among LIB cell components, direct contact between cathode and anode current collectors is most critical to the ISC behavior, yet is still relatively uninvestigated. In the current study, we analyze the effect of heterogeneity of current collector on the temperature increase of LIB cells subjected to mechanical abuse. The cathode current collector is modified by surface notches, so that it becomes effectively brittle and the ISC site can be isolated. Results from impact tests on LIB cells with modified current collectors suggest that their temperature increase can be negligible. The critical parameters include the failure strain and the failure work of modified current collector, both of which are related to the notch depth.

MgB2-based superconductors for fault current limiters

NASA Astrophysics Data System (ADS)

Sokolovsky, V.; Prikhna, T.; Meerovich, V.; Eisterer, M.; Goldacker, W.; Kozyrev, A.; Weber, H. W.; Shapovalov, A.; Sverdun, V.; Moshchil, V.

2017-02-01

A promising solution of the fault current problem in power systems is the application of fast-operating nonlinear superconducting fault current limiters (SFCLs) with the capability of rapidly increasing their impedance, and thus limiting high fault currents. We report the results of experiments with models of inductive (transformer type) SFCLs based on the ring-shaped bulk MgB2 prepared under high quasihydrostatic pressure (2 GPa) and by hot pressing technique (30 MPa). It was shown that the SFCLs meet the main requirements to fault current limiters: they possess low impedance in the nominal regime of the protected circuit and can fast increase their impedance limiting both the transient and the steady-state fault currents. The study of quenching currents of MgB2 rings (SFCL activation current) and AC losses in the rings shows that the quenching current density and critical current density determined from AC losses can be 10-20 times less than the critical current determined from the magnetization experiments.

Critical thinking dispositions among newly graduated nurses

PubMed Central

Wangensteen, Sigrid; Johansson, Inger S; Björkström, Monica E; Nordström, Gun

2010-01-01

wangensteen s., johansson i.s., björkström m.e. & nordström g. (2010) Critical thinking dispositions among newly graduated nurses. Journal of Advanced Nursing66(10), 2170–2181. Aim The aim of the study was to describe critical thinking dispositions among newly graduated nurses in Norway, and to study whether background data had any impact on critical thinking dispositions. Background Competence in critical thinking is one of the expectations of nursing education. Critical thinkers are described as well-informed, inquisitive, open-minded and orderly in complex matters. Critical thinking competence has thus been designated as an outcome for judging the quality of nursing education programmes and for the development of clinical judgement. The ability to think critically is also described as reducing the research–practice gap and fostering evidence-based nursing. Methods A cross-sectional descriptive study was performed. The data were collected between October 2006 and April 2007 using the California Critical Thinking Disposition Inventory. The response rate was 33% (n= 618). Pearson’s chi-square tests were used to analyse the data. Results Nearly 80% of the respondents reported a positive disposition towards critical thinking. The highest mean score was on the Inquisitiveness subscale and the lowest on the Truth-seeking subscale. A statistically significant higher proportion of nurses with high critical thinking scores were found among those older than 30 years, those with university education prior to nursing education, and those working in community health care. Conclusion Nurse leaders and nurse teachers should encourage and nurture critical thinking among newly graduated nurses and nursing students. The low Truth-seeking scores found may be a result of traditional teaching strategies in nursing education and might indicate a need for more student-active learning models. PMID:20384637

Purging sensitive science instruments with nitrogen in the STS environment

NASA Technical Reports Server (NTRS)

Lumsden, J. M.; Noel, M. B.

1983-01-01

Potential contamination of extremely sensitive science instruments during prelaunch, launch, and earth orbit operations are a major concern to the Galileo and International Solar Polar Mission (ISPM) Programs. The Galileo Program is developing a system to purify Shuttle supplied nitrogen gas for in-flight purging of seven imaging and non-imaging science instruments. Monolayers of contamination deposited on critical surfaces can degrade some instrument sensitivities as much as fifty percent. The purging system provides a reliable supply of filtered and fried nitrogen gas during these critical phases of the mission when the contamination potential is highest. The Galileo and ISPM Programs are including the system as Airborne Support Equipment (ASE).

Left Behind: The Status of Black Women in Higher Education Administration

ERIC Educational Resources Information Center

Miles, Sandra

2012-01-01

This quantitative study examines the current status of Black women higher education administrators in comparison to other higher education administrators of another race and/or gender. Specifically, years of service, social support, highest degree attained, income level, and current title held was analyzed to evaluate the actual levels of…

Evidence of Spin-Injection-Induced Cooper Pair Breaking in Perovskite Ferromagnet-Insulator-Superconductor Heterostructures via Pulsed Current Measurements

NASA Technical Reports Server (NTRS)

Yeh, N. C.; Samoilov, A. V.; Veasquez, R. P.; Li, Y.

1998-01-01

The effect of spin-polarized currents on the critical current densities of cuprate superconductors is investigated in perovskite ferromagnet-insulator-superconductor heterostructures with a pulsed current technique.

Geographic Access to US Neurocritical Care Units Registered with the Neurocritical Care Society

PubMed Central

Shutter, Lori A.; Branas, Charles C.; Adeoye, Opeolu; Albright, Karen C.; Carr, Brendan G.

2018-01-01

Background Neurocritical care provides multidisciplinary, specialized care to critically ill neurological patients, yet an understanding of the proportion of the population able to rapidly access specialized Neurocritical Care Units (NCUs) in the United States is currently unknown. We sought to quantify geographic access to NCUs by state, division, region, and for the US as a whole. In addition, we examined how mode of transportation (ground or air ambulance), and prehospital transport times affected population access to NCUs. Methods Data were obtained from the Neurocritical Care Society (NCS), US Census Bureau and the Atlas and Database of Air Medical Services. Empirically derived prehospital time intervals and validated models estimating prehospital ground and air travel times were used to calculate total prehospital times. A discrete total prehospital time interval was calculated for each small unit of geographic analysis (block group) and block group populations were summed to determine the proportion of Americans able to reach a NCU within discrete time intervals (45, 60, 75, and 90 min). Results are presented for different geographies and for different modes of prehospital transport (ground or air ambulance). Results There are 73 NCUs in the US using ground transportation alone, 12.8, 20.5, 27.4, and 32.6% of the US population are within 45, 60, 75, and 90 min of an NCU, respectively. Use of air ambulances increases access to 36.8, 50.4, 60, and 67.3 within 45, 60, 75, and 90 min, respectively. The Northeast has the highest access rates in the US using ground ambulances and for 45, 60, and 75 min transport times with the addition of air ambulances. At 90 min, the West has the highest access rate. The Southern region has the lowest ground and air access to NCUs access rates for all transport times. Conclusions Using NCUs registered with the NCS, current geographic access to NCUs is limited in the US, and geographic disparities in access to care exist. While additional NCUs may exist beyond those identified by the NCS database, we identify geographies with limited access to NCUs and offer a population-based planning perspective on the further development of the US neurocritical care system. PMID:22045246

Influences on adolescent self-esteem in multicultural Canadian secondary schools.

PubMed

Khanlou, Nazilla

2004-01-01

Abstract This study examined the global and current self-esteem levels of adolescents in a community sample of 550 secondary school students in Canada. A cross-sectional design and the survey method were used. Respondents' individual (age and gender) and environmental (cultural background, acculturating group, family circumstances, and perception of support) attributes were considered. Influences that promoted or challenged their current self-esteem were examined. Eighteen percent of respondents and 43.4% of respondents' parents were immigrants. When the Rosenberg Self-Esteem scale was used, 27.6% of respondents had the highest global self-esteem level; when the Current Self-Esteem scale was used, 12.7% had the highest current self-esteem level. A significant gender difference was found, with male adolescents having higher self-esteem. The results indicate that, although self-esteem promotion can benefit from lifestyle-oriented activities, its growth takes place in the larger context of adolescents' relationships, school-related experiences, achievements, and attitudes toward themselves. The study findings can contribute to mental health promotion strategies in multicultural and immigrant-receiving community settings.

From Lean Times to Enrollment Declines: The Governor's Commission on the Future of Higher Education in Michigan. ASHE Annual Meeting Paper.

ERIC Educational Resources Information Center

Widmayer, Patricia

Conditions in higher education in Michigan and the role of the Governor's Commission on the Future of Higher Education in Michigan are highlighted. The average college tuition rate in Michigan is the highest in the nation, and a critical maintenance and equipment problem exists. The Commission is composed of knowledgeable persons without vested…

Apples and Oranges: Comparing the Backgrounds and Academic Trajectories of International Baccalaureate (IB) Students to a Matched Comparison Group

ERIC Educational Resources Information Center

May, Henry; Rodriguez, Awilda; Sirinides, Philip M.; Perna, Laura W.; Yee, April; Ransom, Tafaya

2013-01-01

As a critical step in understanding the impacts of IB, the analyses presented in this report examined the selection mechanisms behind IB participation across Florida, the state with the second highest representation of IB programs in the nation. We use longitudinal student and school-level data from 1995 through 2009 from the Florida K-20…

High voltage and high current density vertical GaN power diodes

DOE PAGES

Fischer, A. J.; Dickerson, J. R.; Armstrong, A. M.; ...

2016-01-01

We report on the realization of a GaN high voltage vertical p-n diode operating at > 3.9 kV breakdown with a specific on-resistance < 0.9 mΩ.cm 2. Diodes achieved a forward current of 1 A for on-wafer, DC measurements, corresponding to a current density > 1.4 kA/cm 2. An effective critical electric field of 3.9 MV/cm was estimated for the devices from analysis of the forward and reverse current-voltage characteristics. Furthermore this suggests that the fundamental limit to the GaN critical electric field is significantly greater than previously believed.

Is there a need for government interventions to adapt energy infrastructures to climate change? A German case study

NASA Astrophysics Data System (ADS)

Groth, Markus; Cortekar, Jörg

2015-04-01

The option of adapting to climate change is becoming more and more important in climate change policy. Hence, responding to climate change now involves both mitigation to address the cause and adaptation as a response to already ongoing and expected changes. These changes also have relevance for the current and future energy sector in Germany. An energy sector that in the course of the German Energiewende also has to deal with a fundamental shift in energy supply from fossil fuel to renewable energies in the next decades. Thereby it needs to be considered that the energy sector is one critical infrastructure in the European Union that needs to be protected. Critical infrastructures can be defined as organisations or facilities of special importance for the country and its people where failure or functional impairment would lead to severe supply bottlenecks, significant disturbance of public order or other dramatic consequences. Regarding the adaptation to climate change, the main question is, whether adaptation options will be implemented voluntarily by companies or not. This will be the case, when the measure is considered a private good and is economically beneficial. If, on the contrary, the measure is considered a public good, additional incentives are needed. Based on a synthesis of the current knowledge regarding the possible impacts of climate change on the German energy sector along its value-added chain, the paper points out, that the power distribution and the grid infrastructure is consistently attributed the highest vulnerability. Direct physical impacts and damages to the transmission and distribution grids, utility poles, power transformers, and relay stations are expected due to more intense extreme weather events like storms, floods or thunderstorms. Furthermore fundaments of utility poles can be eroded and relay stations or power transformers can be flooded, which might cause short circuits etc. Besides these impacts causing damage to the physical infrastructure, there might also occur efficiency losses in electricity transmission due to very high or very low temperatures. While vulnerabilities in power generation primarily result in efficiency losses, interferences on the grid level could cause power outages with cascade effects influencing other sectors of society and economy. The paper argues that these possible impacts of a changing climate should be taken into account in the upcoming infrastructure projects in the course of the Energiewende. Therefore governmental intervention - like legal obligations or incentives by the use of economic instruments - are for example justifiable regarding measures to adapt the grid infrastructure as a critical infrastructure that needs to be protected against current and future impacts of climate change.

Perceptions of nursing students after performing an individual activity designed to develop their critical thinking: The "critical card" tool.

PubMed

Urcola-Pardo, Fernando; Blázquez-Ornat, Isabel; Anguas-Gracia, Ana; Gasch-Gallen, Ángel; Germán-Bes, Concepción

2018-03-01

Critical thinking in Health Sciences is among the transversal competences in the Nursing Degree. The critical card is a tool of individual learning, designed to develop critical thinking, and set in the process of environmental health learning. Every student must perform the activity to obtain the highest qualification in Community Health Nursing subject. The aim of this project was to evaluate this learning tool using the students' perceptions after its performance. The evaluation was based on the answers to a questionnaire obtained from the third course students of Nursing Degree at the University of Zaragoza. The questionnaire was made up of 14 Likert-type questions, grouped in four dimensions. The student participation rate was higher than 50%. The analysis of the questionnaire obtained 67,8% positive answers. The variability between dimensions ranged between 49% of positive answers for application in other subjects and 87% of positive answers for the improvements applicable to the instrument. The students coincided in indicating that the critical card is a useful learning tool and could be applicable in other subjects. However, the weight it is given in the global evaluation of the subject is considered to be too low, considering the time used to complete the activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Global trends in critical values practices and their harmonization.

PubMed

Kost, Gerald J; Hale, Kristin N

2011-02-01

The objectives of this article were 1) to identify current trends in critical values practices in North America, Europe, and other regions; 2) to describe progress toward harmonization of critical limits; and 3) to synthesize strategies that will encourage global consensus. Critical limits are described in national surveys. Critical value practices are guided by federal statutes, The Joint Commission regulations, and accreditation requirements in the US; by provincial healthcare agencies in Canada; by thought leaders and ISO EN 15189:2007 in Europe; and in SE Asia, mostly by ad hoc policies lacking statutory grip. Review of databases, literature, websites, federal statutes, litigation, official policies, current affairs, and accreditation agency requirements. Practical strategies will accelerate harmonization of critical values practices, as follows: a) continue national and international survey comparisons; b) clarify age, ethnic, and subject dependencies; c) standardize qualitative and quantitative decision levels for urgent clinician notification; d) monitor compliance and timeliness for safety; and e) alert high frequencies of critical values related to adverse events. New expectations and communication technologies present opportunities for enhanced performance using wireless closed-loop reporting with recipient acknowledgment to reduce phone calls and improve efficiency. Hospitals worldwide can benefit from developing consensus for critical values practices.

Angular dependence of critical current density and magnetoresistance of sputtered high-T{sub c}-films

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

Geerkens, A.; Frenck, H.J.; Ewert, S.

1994-12-31

The angular dependence of the critical current density and the magnetoresistance of high-T{sub c}-films in high and low magnetic fields and for different temperatures were measured to investigate the flux pinning and the superconducting properties. A comparison of the results for the different superconductors shows their increasing dependence on the angle {Theta} between the magnetic field and the c-axis of the film due to the anisotropy of the chosen superconductor. Furthermore the influence of the current direction to the {Theta}-rotation plane is discussed.

Analysis of critical thinking ability in direct current electrical problems solving

NASA Astrophysics Data System (ADS)

Hartono; Sunarno, Widha; Sarwanto; Arya Nugraha, Dewanta

2017-11-01

This study concern on analyzing the ability of students in critical thinking skills on the subject matter of direct current electricity. Samples were taken using purposive random sampling consisted of 32 students of grade XI, Multimedia 1, SMK Negeri 3 Surakarta in academic year 2016/2017. This study used descriptive quantitative method. The data were collected using tests and interviews regarding the subject matter of direct current electricity. Based on the results, students are getting some difficulties in solving problem in indicator 4. The average of students’ correct answer is 62.8%.

Angular dependence of critical current density and magnetoresistance of sputtered high-T(sub c)-films

NASA Technical Reports Server (NTRS)

Geerkens, A.; Meven, M.; Frenck, H.-J.; Ewert, S.

1995-01-01

The angular dependence of the critical current density and the magnetoresistance of high-T(sub c)-films in high and low magnetic fields and for different temperatures were measured to investigate the flux pinning and the superconducting properties. A comparison of the results for the different superconductors shows their increasing dependence on the angle Theta between the magnetic field and the c-axis of the film due to the anisotropy of the chosen superconductor. Furthermore the influence of the current direction to the Theta-rotation plane is discussed.

Effectiveness of past and current critical incident analysis on reflective learning and practice change.

PubMed

Vachon, Brigitte; LeBlanc, Jeannette

2011-09-01

Critical incident analysis (CIA) is one of the strategies frequently used to facilitate reflective learning. It involves the thorough description and analysis of an authentic and experienced event within its specific context. However, CIA has also been described as having the potential to expose vulnerabilities, threaten learners' coping mechanisms and increase rather than reduce their anxiety levels. The aim of this study was to compare the analysis of current critical incidents with that of past critical incidents, and to further explore why and how the former is more conducive to reflective learning and practice change than the latter. A collaborative research study was conducted. Eight occupational therapists were recruited to participate in a reflective learning group that convened for 12 meetings held over a 15-month period. The group facilitator planned and adapted the learning strategies to be used to promote reflective learning and guided the group process. Critical incident analysis represented the main activity carried out in the group discussions. The data collected were analysed using the grounded theory method. Three phenomena were found to differentiate between the learning contexts created by the analysis of, respectively, past and current critical incidents: attitudinal disposition; legitimacy of purpose, and the availability of opportunities for experimentation. Analysis of current clinical events was found to improve participants' motivation to self-evaluate, to increase their self-efficacy, and to help them transfer learning into action and to progressively self-regulate. The results of this collaborative research study suggest that the analysis of current clinical events in order to promote reflection offers a safer and more constructive learning environment than does the analysis of incidents that have occurred in the past. This learning strategy is directly grounded in health professional practice. The remaining challenge for continuing education providers is that of creating conditions conducive to its use. © Blackwell Publishing Ltd 2011.

Concurrent Data Elicitation Procedures, Processes, and the Early Stages of L2 Learning: A Critical Overview

ERIC Educational Resources Information Center

Leow, Ronald P.; Grey, Sarah; Marijuan, Silvia; Moorman, Colleen

2014-01-01

Given the current methodological interest in eliciting direct data on the cognitive processes L2 learners employ as they interact with L2 data during the early stages of the learning process, this article takes a critical and comparative look at three concurrent data elicitation procedures currently employed in the SLA literature: Think aloud (TA)…

No Good Wars: Teaching the History of Modern American Wars as a Means of Resisting Current Ones

ERIC Educational Resources Information Center

Long, Kenneth

2008-01-01

In the fall 2005 semester, the author designed a course in the history of America's modern wars hoping to encourage students to criticize and oppose the country's current aggressions in Afghanistan and Iraq. Surveys of student attitude change suggest that the course did promote criticism but did far less to facilitate student activism. The author…

Critical Infrastructures: Background, Policy, and Implementation

DTIC Science & Technology

2006-04-18

initially approved. The current review process for such purchases, implemented under authority of the Exon- Florio provision of the Defense Production Act (50...legislative proposals “broaden” coverage of Exon- Florio to include the purchase of assets associated with critical infrastructure. As currently written...Exon- Florio covers persons engaged in interstate commerce. While this covers a broad range of “persons,” extending beyond those that might be part

Teaching the Banking System According to Critical Education. A Study of a Schoolbook on Economics

ERIC Educational Resources Information Center

Vaina, Maria; Katidioti, Evaggelia; Ktitikos, Antonis

2013-01-01

The main objective of the current paper is to establish the deficiencies of teaching Economics in the Greek educational system. It also proposes critical education as a way of partially overcoming these issues and the way it can contribute to the protection of the everyday man and woman against the rising and current existential threats of the…

Implementing a Grant Proposal Writing Exercise in Undergraduate Science Courses to Incorporate Real-World Applications and Critical Analysis of Current Literature

ERIC Educational Resources Information Center

Cole, Kathryn E.; Inada, Maki; Smith, Andrew M.; Haaf, Michael P.

2013-01-01

Writing is an essential part of a successful career in science. As such, many undergraduate science courses have begun to implement writing assignments that reflect "real-world" applications and focus on a critical analysis of current literature; these assignments are often in the form of a review or a research proposal. The…

Space-time mapping of wasting among children under the age of five years in Somalia from 2007 to 2010.

PubMed

Kinyoki, Damaris K; Berkley, James A; Moloney, Grainne M; Odundo, Elijah O; Kandala, Ngianga-Bakwin; Noor, Abdisalan M

2016-02-01

To determine the sub-national seasonal prevalence and trends in wasting from 2007 to 2010 among children aged 6-59 months in Somalia using remote sensing and household survey data from nutritional surveys. Bayesian hierarchical space-time model was implemented using a stochastic partial differential equation (SPDE) approach in integrated nested Laplace approximations (INLA) to produce risk maps of wasting at 1 × 1 km(2) spatial resolution and predict to seasons in each year of study from 2007 to 2010. The prevalence of wasting was generally at critical levels throughout the country, with most of the areas remaining in the upper classes of critical and very critical levels. There was minimal variation in wasting from year-to-year, but a well-defined seasonal variation was observed. The mean difference of the prevalence of wasting between the dry and wet season ranges from 0% to 5%. The risks of wasting in the South Central zone were highest in the Gedo (37%) and Bay (32%) regions. In North East zone the risk was highest in Nugaal (25%) and in the North West zone the risk was high in Awdal and Woqooyi Galbeed regions with 23%. There was a clear seasonal variation in wasting with minimal year-to-year variability from 2007 to 2010 in Somalia. The prevalence was high during the long dry season, which affects the prevalence in the preceding long rainy season. Understanding the seasonal fluctuations of wasting in different locations and at different times is important to inform timely interventions. Copyright © 2016. Published by Elsevier Ltd.

Improving risk classification of critical illness with biomarkers: a simulation study

PubMed Central

Seymour, Christopher W.; Cooke, Colin R.; Wang, Zheyu; Kerr, Kathleen F.; Yealy, Donald M.; Angus, Derek C.; Rea, Thomas D.; Kahn, Jeremy M.; Pepe, Margaret S.

2012-01-01

Purpose Optimal triage of patients at risk of critical illness requires accurate risk prediction, yet little data exists on the performance criteria required of a potential biomarker to be clinically useful. Materials and Methods We studied an adult cohort of non-arrest, non-trauma emergency medical services encounters transported to a hospital from 2002–2006. We simulated hypothetical biomarkers increasingly associated with critical illness during hospitalization, and determined the biomarker strength and sample size necessary to improve risk classification beyond a best clinical model. Results Of 57,647 encounters, 3,121 (5.4%) were hospitalized with critical illness and 54,526 (94.6%) without critical illness. The addition of a moderate strength biomarker (odds ratio=3.0 for critical illness) to a clinical model improved discrimination (c-statistic 0.85 vs. 0.8, p<0.01), reclassification (net reclassification improvement=0.15, 95%CI: 0.13,0.18), and increased the proportion of cases in the highest risk categoryby+8.6% (95%CI: 7.5,10.8%). Introducing correlation between the biomarker and physiological variables in the clinical risk score did not modify the results. Statistically significant changes in net reclassification required a sample size of at least 1000 subjects. Conclusions Clinical models for triage of critical illness could be significantly improved by incorporating biomarkers, yet, substantial sample sizes and biomarker strength may be required. PMID:23566734

Attention enhances multi-voxel representation of novel objects in frontal, parietal and visual cortices.

PubMed

Woolgar, Alexandra; Williams, Mark A; Rich, Anina N

2015-04-01

Selective attention is fundamental for human activity, but the details of its neural implementation remain elusive. One influential theory, the adaptive coding hypothesis (Duncan, 2001, An adaptive coding model of neural function in prefrontal cortex, Nature Reviews Neuroscience 2:820-829), proposes that single neurons in certain frontal and parietal regions dynamically adjust their responses to selectively encode relevant information. This selective representation may in turn support selective processing in more specialized brain regions such as the visual cortices. Here, we use multi-voxel decoding of functional magnetic resonance images to demonstrate selective representation of attended--and not distractor--objects in frontal, parietal, and visual cortices. In addition, we highlight a critical role for task demands in determining which brain regions exhibit selective coding. Strikingly, representation of attended objects in frontoparietal cortex was highest under conditions of high perceptual demand, when stimuli were hard to perceive and coding in early visual cortex was weak. Coding in early visual cortex varied as a function of attention and perceptual demand, while coding in higher visual areas was sensitive to the allocation of attention but robust to changes in perceptual difficulty. Consistent with high-profile reports, peripherally presented objects could also be decoded from activity at the occipital pole, a region which corresponds to the fovea. Our results emphasize the flexibility of frontoparietal and visual systems. They support the hypothesis that attention enhances the multi-voxel representation of information in the brain, and suggest that the engagement of this attentional mechanism depends critically on current task demands. Copyright © 2015 Elsevier Inc. All rights reserved.

Insect Residue Contamination on Wing Leading Edge Surfaces: A Materials Investigation for Mitigation

NASA Technical Reports Server (NTRS)

Lorenzi, Tyler M.; Wohl, Christopher J.; Penner, Ronald K.; Smith, Joseph G.; Siochi, Emilie J.

2011-01-01

Flight tests have shown that residue from insect strikes on aircraft wing leading edge surfaces may induce localized transition of laminar to turbulent flow. The highest density of insect populations have been observed between ground level and 153 m during light winds (2.6 -- 5.1 m/s), high humidity, and temperatures from 21 -- 29 C. At a critical residue height, dependent on the airfoil and Reynolds number, boundary layer transition from laminar to turbulent results in increased drag and fuel consumption. Although this represents a minimal increase in fuel burn for conventional transport aircraft, future aircraft designs will rely on maintaining laminar flow across a larger portion of wing surfaces to reduce fuel burn during cruise. Thus, insect residue adhesion mitigation is most critical during takeoff and initial climb to maintain laminar flow in fuel-efficient aircraft configurations. Several exterior treatments investigated to mitigate insect residue buildup (e.g., paper, scrapers, surfactants, flexible surfaces) have shown potential; however, implementation has proven to be impractical. Current research is focused on evaluation of wing leading edge surface coatings that may reduce insect residue adhesion. Initial work under NASA's Environmentally Responsible Aviation Program focused on evaluation of several commercially available products (commercial off-the-shelf, COTS), polymers, and substituted alkoxy silanes that were applied to aluminum (Al) substrates. Surface energies of these coatings were determined from contact angle data and were correlated to residual insect excrescence on coated aluminum substrates using a custom-built "bug gun." Quantification of insect excrescence surface coverage was evaluated by a series of digital photographic image processing techniques.

Development of strong vortex pinning and very high Jc in iron based superconductors

NASA Astrophysics Data System (ADS)

Tarantini, Chiara

2015-03-01

Ba(Fe1-xCox)2 As2 (Ba122) is the most tunable of the Fe-based superconductors (FBS) in terms of its acceptance of high densities of secondary phases capable of acting as effective pinning centers without depressing the properties of the superconducting matrix. It has been demonstrated that self-assembled nanorods made of Ba-Fe-O generate a strong correlated pinning along the c-axis, enhancing the critical current density, Jc, in this direction and reducing the Jc anisotropy. However, when 20% of secondary phases are introduced, the reduction of the cross-section becomes significant, decreasing the low field performance. In order to overcome this issue, artificially introduced pinning centers can be added by multilayer deposition producing an almost isotropic increase of Jc. Moreover, FBS are very sensitive to strain, allowing an important enhancement in the critical temperature, Tc, of the material. It will be shown that strain induced by the substrate can further improve Jc of both single and multilayer films by more than expected because of the Tc increase. The multilayer deposition of Ba122 on CaF2 increases the pinning force density, Fp, by more than 60% compared to a single layer film, reaching a maximum of 84 GN/m3 at 22.5T and 4.2 K, the highest value ever reported in any 122 phase. This work shows that the in-field performance of Ba122 widely exceeds that of Nb3Sn above 10T, attracting attention for possible applications.

Pluralism and heterogeneity as criticism: Undergraduate history and systems of psychology courses in Argentinian psychology education (1983-2017).

PubMed

Fierro, Catriel

2018-05-01

Multiple studies have analyzed the aims, resources, and approaches to undergraduate and graduate history of psychology education in several countries. Argentina is one of the countries with the highest historiographical production in Latin America. However, to date, there are no published studies on the collective debates among professionals, institutions, and associations that were instrumental in the development of the historiography of science becoming a mandatory part of the curriculum in Argentinian psychology programs. This study describes and analyzes the role of undergraduate history of psychology courses in official debates that took place during the last 30 years regarding Argentinian psychologists' training and education, in the context of regional and international historiography. Data was retrieved from several primary sources, such as minutes and official dossiers, working documents on accreditation standards, and nationwide curricular diagnoses on undergraduate psychology education, as well as individual scholars' ideas. Our findings suggest that, in line with regional and international historiography, history of psychology courses in Argentina have repeatedly been considered as core content in debates and discussions about psychology education, from the restoration of democracy in 1983 to the present day, in which they are currently considered to be mandatory minimum curricular content. Although throughout its history Argentinian psychology has largely been reduced to the teaching of Freudian and Lacanian psychoanalysis, historical education has been perceived as a gateway toward a more plural and critical local psychology. We conclude by discussing some potential and actual concerns that pose a threat to Argentinian undergraduate history courses. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Evaluation of Patient Safety Indicators in Semnan City Hospitals by Using the Patient Safety Friendly Hospital Initiative (PSFHI).

PubMed

Babamohamadi, Hassan; Nemati, Roghayeh Khabiri; Nobahar, Monir; Keighobady, Seifullah; Ghazavi, Soheila; Izadi-Sabet, Farideh; Najafpour, Zhila

2016-08-01

Nowadays, patient safety issue is among one of the main concerns of the hospital policy worldwide. This study aimed to evaluate the patient safety status in hospitals affiliated to Semnan city, using the WHO model for Patient Safety Friendly Hospital Initiatives (PSFHI) in summer 2014. That was a cross sectional descriptive study that addressed patient safety , which explained the current status of safety in the Semnan hospitals using by instrument of Patient safety friendly initiative standards (PSFHI). Data was collected from 5 hospitals in Semnan city during four weeks in May 2014. The finding of 5 areas examined showed that some components in critical standards had disadvantages. Critical standards of hospitals including areas of leadership and administration, patient and public involvement and safe evidence-based clinical practice, safe environment with and lifetime education in a safe and secure environment were analyzed. The domain of patient and public involvement obtained the lowest mean score and the domain of safe environment obtained the highest mean score in the surveyed hospitals. All the surveyed hospitals had a poor condition regarding standards based on patient safety. Further, the identified weak points are almost the same in the hospitals. Therefore, In order to achieve a good level of all aspects of the protocol, the goals should be considered in the level of strategic planning at hospitals. An effective execution of patient safety creatively may depend on the legal infrastructure and enforcement of standards by hospital management, organizational liability to expectation of patients, safety culture in hospitals.

Chitin Nanofibers Extracted from Crab Shells in Broadband Visible Antireflection Coatings with Controlling Layer-by-Layer Deposition and the Application for Durable Antifog Surfaces.

PubMed

Manabe, Kengo; Tanaka, Chie; Moriyama, Yukari; Tenjimbayashi, Mizuki; Nakamura, Chiaki; Tokura, Yuki; Matsubayashi, Takeshi; Kyung, Kyu-Hong; Shiratori, Seimei

2016-11-23

Reflection from various surfaces of many optical systems, such as photovoltaics and displays, is a critical issue for their performance, and antireflection coatings play a pivotal role in a wide variety of optical technologies, reducing light reflectance loss and hence maximizing light transmission. With the current movement toward optically transparent polymeric media and coatings for antireflection technology, the need for economical and environmentally friendly materials and methods without dependence on shape or size has clearly been apparent. Herein, we demonstrate novel antireflection coatings composed of chitin nanofibers (CHINFs), extracted from crab shell as a biomass material through an aqueous-based layer-by-layer self-assembly process to control the porosity. Increasing the number of air spaces inside the membrane led low refractive index, and precise control of refractive index derived from the stacking of the CHINFs achieved the highest transmittance with investigating the surface structure and the refractive index depending on the solution pH. At a wavelength of 550 nm, the transmittance of the coatings was 96.4%, which was 4.8% higher than that of a glass substrate, and their refractive index was 1.30. Further critical properties of the films were the durability and the antifogging performance derived from the mechanical stability and hydrophilicity of CHINFs, respectively. The present study may contribute to a development of systematically designed nanofibrous films which are suitable for optical applications operating at a broadband visible wavelength with durability and antifog surfaces.

Critical Care Nurses' Reasons for Poor Attendance at a Continuous Professional Development Program.

PubMed

Viljoen, Myra; Coetzee, Isabel; Heyns, Tanya

2016-12-01

Society demands competent and safe health care, which obligates professionals to deliver quality patient care using current knowledge and skills. Participation in continuous professional development programs is a way to ensure quality nursing care. Despite the importance of continuous professional development, however, critical care nurse practitioners' attendance rates at these programs is low. To explore critical care nurses' reasons for their unsatisfactory attendance at a continuous professional development program. A nominal group technique was used as a consensus method to involve the critical care nurses and provide them the opportunity to reflect on their experiences and challenges related to the current continuous professional development program for the critical care units. Participants were 14 critical care nurses from 3 critical care units in 1 private hospital. The consensus was that the central theme relating to the unsatisfactory attendance at the continuous professional development program was attitude. In order of importance, the 4 contributing priorities influencing attitude were communication, continuous professional development, time constraints, and financial implications. Attitude relating to attending a continuous professional development program can be changed if critical care nurses are aware of the program's importance and are involved in the planning and implementation of a program that focuses on the nurses' individual learning needs. ©2016 American Association of Critical-Care Nurses.

Critical infrastructure protection.

PubMed

Deitz, Kim M

2012-01-01

Current government policies for protecting the nation's critical infrastructure are described in this article which focuses on hospital disaster planning and incident management and the significant role of Security in infrastructure protection

Charge imbalance and Josephson effects in superconductor-normal metal mesoscopic structures

NASA Astrophysics Data System (ADS)

Volkov, A. F.

2007-11-01

We consider a SBS Josephson junction the superconducting electrodes S of which are in contact with normal metal reservoirs ( B means a barrier). For temperatures near Tc we calculate an effective critical current Ic* and the resistance of the system at the currents I

Engineered pinning landscapes for enhanced 2G coil wire

DOE PAGES

Rupich, Martin W.; Sathyamurthy, Srivatsan; Fleshler, Steven; ...

2016-04-01

We demonstrate a twofold increase in the in-field critical current of AMSC's standard 2G coil wire by irradiation with 18-MeV Au ions. The optimum pinning enhancement is achieved with a dose of 6 × 10 11 Au ions/cm 2. Although the 77 K, self-field critical current is reduced by about 35%, the in-field critical current (H//c) shows a significant enhancement between 4 and 50 K in fields > 1 T. The process was used for the roll-to-roll irradiation of AMSC's standard 46-mm-wide production coated conductor strips, which were further processed into standard copper laminated coil wire. The long-length wires showmore » the same enhancement as attained with short static irradiated samples. The roll-to-roll irradiation process can be incorporated in the standard 2G wire manufacturing, with no modifications to the current process. In conclusion, the enhanced performance of the wire will benefit rotating machine and magnet applications.« less

NASA Astrophysics Data System (ADS)

Good, J.; Bracanovic, D.

The development of High Temperature Superconductors (HTS) conductors makes it possible to build very high field superconducting magnets up to at least 25 T. Previously, the only way to obtain a steady field of 25 T for research would be to use water cooled copper solenoids. To achieve 25 T in a 50 mm working space would require about 10 MW of power with a large water cooling plant to carry away the heat. With such high powers involved it is difficult to have a stable and quiet magnetic field environment in which to make sensitive measurements such as NMR. Both capital and operating costs are high so few such facilities exist worldwide. This makes a superconducting magnet of 25 T a very attractive proposition. Figure 1 shows that the critical current of HTS as compared to NbTi and NbSn. The latter can be used up to a limit of about 20 T at 4.2 K. The HTS on the other hand shows the potential of much higher fields. The two main issues in magnet design are the maximum critical current and the maximum stress that a conductor or coil structure can support. For the inner sections of the coil the forces are modest but as the diameter increases towards the outside of the coil hoop stress becomes the dominant issue. Cryogenic has built a magnet system with first generation BSCCO conductor. It is designed to run at 4.2 K. It has a three section design, two of conventional superconductor and one of HTS. • The outer winding is made from NbTi giving a field of 9 T, in a bore of 225 mm. The coil is made from 21 km of NbTi wire graded from 1 to 0.6 mm diameter. • A middle coil of NbSn bronze route conductor providing a field of 14 T in 140 mm diameter. • An inner set of HTS coils. These are in the form of 3 coaxial windings made from silver matrix BSCCO conductor supplied by American Superconductor. This conductor has a critical current of 100 A at 77 K in zero field. At 4 K in low field the current is very much higher. The set of three BSCCO windings has a gauss per amp of 157 and when run on its own at a current of 300 A provides a field of 4.7 T, although currents above 275 A begin to show significant resistive losses in the conductor. The inner BSCCO coils are separately powered from the outer magnet. In a test of the full magnet system the BSCCO coil is ramped up at various background fields up to 13 T. The resulting voltage loss across the BSCCO is shown in Fig. 2. This test shows that the BSCCO conductor can operate up to 275 A quite successfully independent of the background field with just a slight increase in resistive losses presumably from the joints between conductor being magneto-resistive or due to flux flow in the conductor. Since the BSCCO coils were made new 2nd generation conductors have become available made from thin films of YBCO on a stainless steel backing. These have a much higher effective current density. A 4 mm wide tape of BSCCO is 0.4 mm thick but carries a similar current to an YBCO tape of 0.01 mm or even 0.05 mm thickness. Table 1 shows the properties of different conductors compared. Interestingly the conductors are not just higher current density but also more flexible and stronger in tension. A new coil has now been produced from 0.1 mm Super Power material of a size that can fit inside the existing winding so that the combination can produce above 6 T providing a total field of 20 T at 4.2 K in a working bore of 38 mm. Now that the new 2nd generation YBCO based conductors have become available it is intended to exchange the BSCCO coils for YBCO windings which will allow this magnet to operate at much higher fields of up to 25 T. At this field it will be the highest field superconducting magnet worldwide. The magnet is housed in a liquid helium cryostat. To reduce helium consumption a powerful 2nd stage cryocooler is fitted to the cryostat. The first stage cools a shield around the liquid helium to 45 K. The second stage has a cooling power of 1.5 W at 4.2 K and is used to recondense helium gas evolved from the magnet. In operation, with no current in the leads to the cryocooler it is able to condense more gas than that evolved from the cryostat so the liquid helium level will increase with time. Except at the highest currents the cryostat is a zero loss magnet system. A cross section of cryostat and magnet is show in Fig 3. The power required for the cryocooler is 6.5 kW while that for the magnet power supplies and ancillary electronics is 2 kW giving a combined power requirement of 8.5 kW. This compares very favourably with the typical value of 10 MW required by a water cooled copper solenoid to achieve the same field. Note from Publisher: This article contains the abstract only.

Imaging White Matter in Human Brainstem

PubMed Central

Ford, Anastasia A.; Colon-Perez, Luis; Triplett, William T.; Gullett, Joseph M.; Mareci, Thomas H.; FitzGerald, David B.

2013-01-01

The human brainstem is critical for the control of many life-sustaining functions, such as consciousness, respiration, sleep, and transfer of sensory and motor information between the brain and the spinal cord. Most of our knowledge about structure and organization of white and gray matter within the brainstem is derived from ex vivo dissection and histology studies. However, these methods cannot be applied to study structural architecture in live human participants. Tractography from diffusion-weighted magnetic resonance imaging (MRI) may provide valuable insights about white matter organization within the brainstem in vivo. However, this method presents technical challenges in vivo due to susceptibility artifacts, functionally dense anatomy, as well as pulsatile and respiratory motion. To investigate the limits of MR tractography, we present results from high angular resolution diffusion imaging of an intact excised human brainstem performed at 11.1 T using isotropic resolution of 0.333, 1, and 2 mm, with the latter reflecting resolution currently used clinically. At the highest resolution, the dense fiber architecture of the brainstem is evident, but the definition of structures degrades as resolution decreases. In particular, the inferred corticopontine/corticospinal tracts (CPT/CST), superior (SCP) and middle cerebellar peduncle (MCP), and medial lemniscus (ML) pathways are clearly discernable and follow known anatomical trajectories at the highest spatial resolution. At lower resolutions, the CST/CPT, SCP, and MCP pathways are artificially enlarged due to inclusion of collinear and crossing fibers not inherent to these three pathways. The inferred ML pathways appear smaller at lower resolutions, indicating insufficient spatial information to successfully resolve smaller fiber pathways. Our results suggest that white matter tractography maps derived from the excised brainstem can be used to guide the study of the brainstem architecture using diffusion MRI in vivo. PMID:23898254

Risk analysis reveals global hotspots for marine debris ingestion by sea turtles.

PubMed

Schuyler, Qamar A; Wilcox, Chris; Townsend, Kathy A; Wedemeyer-Strombel, Kathryn R; Balazs, George; van Sebille, Erik; Hardesty, Britta Denise

2016-02-01

Plastic marine debris pollution is rapidly becoming one of the critical environmental concerns facing wildlife in the 21st century. Here we present a risk analysis for plastic ingestion by sea turtles on a global scale. We combined global marine plastic distributions based on ocean drifter data with sea turtle habitat maps to predict exposure levels to plastic pollution. Empirical data from necropsies of deceased animals were then utilised to assess the consequence of exposure to plastics. We modelled the risk (probability of debris ingestion) by incorporating exposure to debris and consequence of exposure, and included life history stage, species of sea turtle and date of stranding observation as possible additional explanatory factors. Life history stage is the best predictor of debris ingestion, but the best-fit model also incorporates encounter rates within a limited distance from stranding location, marine debris predictions specific to the date of the stranding study and turtle species. There is no difference in ingestion rates between stranded turtles vs. those caught as bycatch from fishing activity, suggesting that stranded animals are not a biased representation of debris ingestion rates in the background population. Oceanic life-stage sea turtles are at the highest risk of debris ingestion, and olive ridley turtles are the most at-risk species. The regions of highest risk to global sea turtle populations are off of the east coasts of the USA, Australia and South Africa; the east Indian Ocean, and Southeast Asia. Model results can be used to predict the number of sea turtles globally at risk of debris ingestion. Based on currently available data, initial calculations indicate that up to 52% of sea turtles may have ingested debris. © 2015 John Wiley & Sons Ltd.

Imaging white matter in human brainstem.

PubMed

Ford, Anastasia A; Colon-Perez, Luis; Triplett, William T; Gullett, Joseph M; Mareci, Thomas H; Fitzgerald, David B

2013-01-01

The human brainstem is critical for the control of many life-sustaining functions, such as consciousness, respiration, sleep, and transfer of sensory and motor information between the brain and the spinal cord. Most of our knowledge about structure and organization of white and gray matter within the brainstem is derived from ex vivo dissection and histology studies. However, these methods cannot be applied to study structural architecture in live human participants. Tractography from diffusion-weighted magnetic resonance imaging (MRI) may provide valuable insights about white matter organization within the brainstem in vivo. However, this method presents technical challenges in vivo due to susceptibility artifacts, functionally dense anatomy, as well as pulsatile and respiratory motion. To investigate the limits of MR tractography, we present results from high angular resolution diffusion imaging of an intact excised human brainstem performed at 11.1 T using isotropic resolution of 0.333, 1, and 2 mm, with the latter reflecting resolution currently used clinically. At the highest resolution, the dense fiber architecture of the brainstem is evident, but the definition of structures degrades as resolution decreases. In particular, the inferred corticopontine/corticospinal tracts (CPT/CST), superior (SCP) and middle cerebellar peduncle (MCP), and medial lemniscus (ML) pathways are clearly discernable and follow known anatomical trajectories at the highest spatial resolution. At lower resolutions, the CST/CPT, SCP, and MCP pathways are artificially enlarged due to inclusion of collinear and crossing fibers not inherent to these three pathways. The inferred ML pathways appear smaller at lower resolutions, indicating insufficient spatial information to successfully resolve smaller fiber pathways. Our results suggest that white matter tractography maps derived from the excised brainstem can be used to guide the study of the brainstem architecture using diffusion MRI in vivo.

Geographic variability in HIV and injection drug use in Ukraine: Implications for integration and expansion of drug treatment and HIV care

PubMed Central

Zaller, Nickolas; Mazhnaya, Alonya; Larney, Sarah; Islam, Zahed; Shost, Alyona; Prokhorova, Tatiana; Rybak, Natasha; Flanigan, Timothy

2015-01-01

Background Ukraine has the highest HIV burden of any European country with much of the current HIV epidemic concentrated among people who inject drugs (PWIDs) and their sexual partners. Opiate substitution therapy (OST) is limited in Ukraine and expansion of OST is urgently needed to help stem the tide of the HIV epidemic. Methods We accessed publicly available data in Ukraine in order to explore geographic variability with respect to prevalence of HIV, PWIDs and OST programmes. Results The regions of Ukraine with the largest number of opioid dependent persons (the south and eastern portions of the country) correspond to the regions with the highest HIV prevalence and HIV incidence. The number of opioid PWIDs per 100,000 population as well as the number of all OST treatment slots per 100,000 varied significantly across the three HIV prevalence categories. Overall, the proportion of individuals receiving either methadone maintenance therapy (MMT) or buprenorphine maintenance therapy (BMT) was quite low: average across categories: 7.3% and 0.4%, respectively. Additionally, less than half of OST patients receiving MMT or BMT were HIV positive patients. Conclusion There is significant geographic variability in both numbers of HIV positive individuals and numbers of PWIDs across Ukraine, however, there may be a more concentrated epidemic among PWIDs in many regions of the country. Scale up of addiction treatment for PWID, especially OST, can have a significant impact on preventing injection related morbidity, such as HIV and HCV infection. Ukraine can learn from the mistakes other nations have made in denying critical treatment opportunities to PWID. PMID:25304049

Geographic variability in HIV and injection drug use in Ukraine: implications for integration and expansion of drug treatment and HIV care.

PubMed

Zaller, Nickolas; Mazhnaya, Alonya; Larney, Sarah; Islam, Zahed; Shost, Alyona; Prokhorova, Tatiana; Rybak, Natasha; Flanigan, Timothy

2015-01-01

Ukraine has the highest HIV burden of any European country with much of the current HIV epidemic concentrated among people who inject drugs (PWIDs) and their sexual partners. Opiate substitution therapy (OST) is limited in Ukraine and expansion of OST is urgently needed to help stem the tide of the HIV epidemic. We accessed publicly available data in Ukraine in order to explore geographic variability with respect to prevalence of HIV, PWIDs and OST programmes. The regions of Ukraine with the largest number of opioid dependent persons (the south and eastern portions of the country) correspond to the regions with the highest HIV prevalence and HIV incidence. The number of opioid PWIDs per 100,000 population as well as the number of all OST treatment slots per 100,000 varied significantly across the three HIV prevalence categories. Overall, the proportion of individuals receiving either methadone maintenance therapy (MMT) or buprenorphine maintenance therapy (BMT) was quite low: average across categories: 7.3% and 0.4%, respectively. Additionally, less than half of OST patients receiving MMT or BMT were HIV positive patients. There is significant geographic variability in both numbers of HIV positive individuals and numbers of PWIDs across Ukraine, however, there may be a more concentrated epidemic among PWIDs in many regions of the country. Scale up of addiction treatment for PWID, especially OST, can have a significant impact on preventing injection related morbidity, such as HIV and HCV infection. Ukraine can learn from the mistakes other nations have made in denying critical treatment opportunities to PWID. Copyright © 2014 Elsevier B.V. All rights reserved.

Development and Dissemination of a Nationwide Helium Database for a National Assessment of Helium Resources.

NASA Astrophysics Data System (ADS)

Brennan, S. T.; East, J. A., II; Garrity, C. P.

2015-12-01

In 2013, Congress passed the Helium Stewardship Act requiring the U.S. Geological Survey (USGS) to undertake a national helium gas resource assessment to determine the nation's helium resources. An important initial component necessary to complete this assessment was the development of a comprehensive database of Helium (He) concentrations from petroleum exploration wells. Because Helium is often used as the carrier gas for compositional analyses for commercial and exploratory oil and gas wells, this limits the available helium concentration data. A literature search in peer-reviewed publications, state geologic survey databases, USGS energy geochemical databases, and the Bureau of Land Management databases provided approximately 16,000 data points from wells that had measurable He concentrations in the gas composition analyses. The data from these wells includes, date of sample collection, American Petroleum Institute well number, formation name, field name, depth of sample collection, and location. The gas compositional analyses, some performed as far back as 1934, do not all have the same level of precision and accuracy, therefore the date of the analysis is critical to the assessment as it indicates the relative amount of uncertainty in the analytical results. Non-proprietary data was used to create a GIS based interactive web interface that allows users to visualize, inspect, interact, and download our most current He data. The user can click on individual locations to see the available data at that location, as well as zoom in and out on a data density map. Concentrations on the map range from .04 mol% (lowest concentration of economic value) to 12% (highest naturally occurring values). This visual interface will allow users to develop a rapid appreciation of the areas with the highest potential for high helium concentrations within oil and gas fields.

The 2012 Chitranjan Ranawat award: intraarticular analgesia after TKA reduces pain: a randomized, double-blinded, placebo-controlled, prospective study.

PubMed

Goyal, Nitin; McKenzie, James; Sharkey, Peter F; Parvizi, Javad; Hozack, William J; Austin, Matthew S

2013-01-01

Postoperative pain after total knee arthroplasty remains one of the most important challenges facing patients undergoing this surgery. Providing a balance of adequate analgesia while limiting the functional impact of regional anesthesia and minimizing opioid side effects is critical to minimize adverse events and improve patient satisfaction. We asked whether bupivacaine delivered through an elastomeric device decreases the (1) patients' perception of pain after TKA; (2) narcotic consumption; and (3) narcotic-related side effects as compared with a placebo. In this prospective, double-blind, placebo-controlled study, all patients received standardized regional anesthesia, a preemptive and multimodal analgesic protocol, and a continuous intraarticular infusion at 5 mL/hour through an elastomeric infusion pump. The patients were randomized to receive either an infusion pump filled with (1) 300 mL of 0.5% bupivacaine, the experimental group (n = 75); or (2) 300 mL of 0.9% normal saline solution, the control group (n = 75). Data concerning postoperative pain levels through a visual analog scale, postoperative opioid consumption, opioid-related side effects, and complications were collected and analyzed. Patients in the experimental group receiving the bupivacaine reported a reduction in pain levels in highest, lowest, and current visual analog scale scores compared with the placebo group on the first postoperative day and highest visual analog scale score on postoperative Day 2 along with a 33% reduction in opioid consumption on postoperative Day 2 and a 54% reduction on postoperative Day 3. In patients undergoing TKA, continuous intraarticular analgesia provided an effective adjunct for pain relief in the immediate postoperative period without the disadvantages encountered with other analgesic methods.

Future water supply and demand in response to climate change and agricultural expansion in Texas

NASA Astrophysics Data System (ADS)

Lee, K.; Zhou, T.; Gao, H.; Huang, M.

2016-12-01

With ongoing global environmental change and an increasing population, it is challenging (to say the least) to understand the complex interactions of irrigation and reservoir systems. Irrigation is critical to agricultural production and food security, and is a vital component of Texas' agricultural economy. Agricultural irrigation currently accounts for about 60% of total water demand in Texas, and recent occurrences of severe droughts has brought attention to the availability and use of water in the future. In this study, we aim to assess future agricultural irrigation water demand, and to estimate how changes in the fraction of crop irrigated land will affect future water availability in Texas, which has the largest farm area and the highest value of livestock production in the United States. The Variable Infiltration Capacity (VIC) model, which has been calibrated and validated over major Texas river basins during the historical period, is employed for this study. The VIC model, coupling with an irrigation scheme and a reservoir module, is adopted to simulate the water management and regulations. The evolution on agricultural land is also considered in the model as a changing fraction of crop for each grid cell. The reservoir module is calibrated and validated based on the historical (1915-2011) storage records of major reservoirs in Texas. The model is driven by statistically downscaled climate projections from Coupled Model Intercomparison Project Phase 5 (CMIP5) model ensembles at a spatial resolution of 1/8°. The lowest (RCP 2.6) and highest (RC P8.5) greenhouse-gas concentration scenarios are adopted for future projections to provide an estimate of uncertainty bounds. We expect that our results will be helpful to assist decision making related to reservoir operations and agricultural water planning for Texas under future climate and environmental changes.

Dual Burden of Malnutrition Among Adolescents of Smallholder Coffee Farming Households of Jimma Zone, Southwest Ethiopia.

PubMed

Hassen, Kalkidan; Gizaw, Getu; Belachew, Tefera

2017-06-01

Substantial evidence is emerging on the coexistence of double burden of malnutrition on adolescents of low-income countries, shaping the health challenges of the upcoming adult generation for the worst. Whether nutritional status markers of adolescents in the cash crop setting are on par with economic gains remains uncertain. Thus, we investigated the nutritional outcomes of adolescents and their determinants in coffee farming households. The survey was carried out in 3 top coffee-producing districts of Jimma Zone, Ethiopia. Five hundred fifty mothers/caregivers and their respective adolescents were selected using multistage random sampling. Anthropometric data were converted into height-for-age and body-mass-index-for-age Z scores using WHO Anthroplus software and analyzed by SPSS for windows. Prevalence of thinness, stunting, and overweight/obesity were 11.6%, 15.6%, and 7.1%, respectively. The odds of stunting among adolescents in households in the lowest wealth tertile was nearly 6-fold higher compared to the highest tertile (adjusted odds ratio [AOR] = 5.6 [2.6-12]). Conversely, the odds of overweight/obesity was higher among adolescents in the households in the middle wealth tertile (AOR = 2.72 [1.08-6.86]) compared to the highest tertile. Adolescents living in households with low-dependent age-groups were more than twice likely to be overweight/obese (AOR = 2.58 [1.06-6.24]). The current study revealed the presence of substantial dual burden of malnutrition. In such a setting, it is critical to draw a fine line and trade-off for eliminating morbidity and mortality of undernutrition, without triggering the risk of overweight/obesity.

Estimating 20-year land-use change and derived CO2 emissions associated with crops, pasture and forestry in Brazil and each of its 27 states.

PubMed

Novaes, Renan M L; Pazianotto, Ricardo A A; Brandão, Miguel; Alves, Bruno J R; May, André; Folegatti-Matsuura, Marília I S

2017-09-01

Land-use change (LUC) in Brazil has important implications on global climate change, ecosystem services and biodiversity, and agricultural expansion plays a critical role in this process. Concerns over these issues have led to the need for estimating the magnitude and impacts associated with that, which are increasingly reported in the environmental assessment of products. Currently, there is an extensive debate on which methods are more appropriate for estimating LUC and related emissions and regionalized estimates are lacking for Brazil, which is a world leader in agricultural production (e.g. food, fibres and bioenergy). We developed a method for estimating scenarios of past 20-year LUC and derived CO 2 emission rates associated with 64 crops, pasture and forestry in Brazil as whole and in each of its 27 states, based on time-series statistics and in accordance with most used carbon-footprinting standards. The scenarios adopted provide a range between minimum and maximum rates of CO 2 emissions from LUC according to different possibilities of land-use transitions, which can have large impacts in the results. Specificities of Brazil, like multiple cropping and highly heterogeneous carbon stocks, are also addressed. The highest CO 2 emission rates are observed in the Amazon biome states and crops with the highest rates are those that have undergone expansion in this region. Some states and crops showing large agricultural areas have low emissions associated, especially in southern and eastern Brazil. Native carbon stocks and time of agricultural expansion are the most decisive factors to the patterns of emissions. Some implications on LUC estimation methods and standards and on agri-environmental policies are discussed. © 2017 John Wiley & Sons Ltd.

2014 Decompression Sickness/Extravehicular Activity Risks Standing Review Panel

NASA Technical Reports Server (NTRS)

Steinberg, Susan; Mahon, Richard; Klaus, David; Neuman, Tom; Pilmanis, Andrew; Regis, David

2014-01-01

The 2014 Decompression Sickness (DCS)/Extravehicular Activity (EVA) Risks Standing Review Panel (from here on referred to as the SRP) met for a site visit in Houston, TX on November 4 - 5, 2014. The SRP reviewed the Research Plans for The Risk of Decompression Sickness and the Risk of Injury and Compromised Performance due to EVA Operations, as well as the Evidence Reports for both of these Risks. The SRP found that the NASA DCS/EVA team did an excellent job of presenting their research plans. The SRP considers it critical that NASA proceeds with the high priority tasks identified in this report (DCS1, DCS3, DCS5). The highest priority is to determine the acceptable DCS and hypoxia risk associated with the planned human exploration beyond low Earth orbit. The risk of DCS is highly dependent upon the pressure within the exploration vehicle. If slightly more hypoxia is permitted then (even with the same percentage of oxygen) the pressure within the exploration vehicle can be lowered thus further mitigating the risk of DCS. The second highest priority is to test and validate the recommended 8.2psi/34% O2 atmosphere. Development of procedures and equipment for human exploration missions are very limited until the results of this testing are completed. The SRP also suggests that DCS7 be separated into two Gaps. Gap DCS7 should deal with DCS treatment while a new Gap should be created to deal with the long-term effects of DCS. The SRP also encourages NASA to increase collaboration with other organizations and pool resources where possible. The current NASA DCS/EVA team has the extensive expertise and a wealth of knowledge in this area. The SRP suggests that increased manpower for this team would be highly productive.

Anaesthetic uptake and washout characteristics of patient circuit tubing with special regard to current decontamination techniques.

PubMed

Gilly, H; Weindlmayr-Goettel, M; Köberl, G; Steinbereithner, K

1992-10-01

The amounts of halothane and isoflurane trapped after exposure for up to 3 h at 2 MAC in commonly used anaesthesia circuit tubing were quantitated by gas chromatography. The decontaminating effects of procedures such as flushing with oxygen, thermal disinfection and/or routine storage were assessed in a similar way. After halothane exposure, anaesthetic content was highest in silicone (398 +/- 55 mg 100 g-1). Lower quantities were found in all other tubings investigated (electrically conductive latex: 64 +/- 4, conductive rubber: 62 +/- 4, polyethylene-vinyl-acetate (PEVA): 293 +/- 10 and 149 +/- 17 for non-conductive corrugated and spiral tubes, respectively, polysulfone (Hytrel): 155 +/- 10 mg 100 g-1). The isoflurane contents were substantially lower (silicone: 278 +/- 23; others: 55 +/- 7, 61 +/- 6, 163 +/- 9 and 86 +/- 8, 74 +/- 4 mg 100 g-1). The tubings' content did not correlate with the material's partition coefficient as full saturation was not achieved during exposure. Decontamination procedures reduced the content of volatile anaesthetics to a variable extent. Conductive latex and rubber showed the highest residual content, even after thermal disinfection and subsequent storage. Twenty-minute flushing with oxygen (8 l min-1) decreased effluent gas concentrations below 5 p.p.m. in all tubings. With silicone, after 1 h flushing, halothane concentrations still exceeded 10 p.p.m. (isoflurane: 8 p.p.m.). It is concluded that urgent decontamination by a 20-min flush warrants the safe re-use of previously 'contaminated' conductive rubber and latex as well as polysulfone tubings in critical situations, e.g. in malignant hyperthermia patients if disposable tubing is not immediately available.(ABSTRACT TRUNCATED AT 250 WORDS)

Recent advances of high voltage AlGaN/GaN power HFETs

NASA Astrophysics Data System (ADS)

Uemoto, Yasuhiro; Ueda, Tetsuzo; Tanaka, Tsuyoshi; Ueda, Daisuke

2009-02-01

We review our recent advances of GaN-based high voltage power transistors. These are promising owing to low on-state resistance and high breakdown voltage taking advantages of superior material properties. However, there still remain a couple of technical issues to be solved for the GaN devices to replace the existing Si-based power devices. The most critical issue is to achieve normally-off operation which is strongly desired for the safety operation, however, it has been very difficult because of the built-in polarization electric field. Our new device called GIT (Gate Injection Transistor) utilizing conductivity modulation successfully achieves the normally-off operation keeping low on-state resistance. The fabricated GIT on a Si substrate exhibits threshold voltage of +1.0V. The obtained on-state resistance and off-state breakdown voltage were 2.6mΩ•cm2 and 800V, respectively. Remaining technical issue is to further increase the breakdown voltage. So far, the reported highest off-state breakdown voltage of AlGaN/GaN HFETs has been 1900V. Overcoming these issues by a novel device structure, we have demonstrated the world highest breakdown voltages of 10400V using thick poly-crystalline AlN as a passivation film and Via-holes through sapphire which enable very efficient layout of the lateral HFET array avoiding any undesired breakdown of passivation films. Since conventional wet or dry etching cannot be used for chemically stable sapphire, high power pulsed laser is used to form the via-holes. The presented GaN power devices demonstrate that GaN is advantageous for high voltage power switching applications replacing currently used Si-based power MOSFETs and IGBTs.

Assessment of provider attitudes toward #naloxone on Twitter.

PubMed

Haug, Nancy A; Bielenberg, Jennifer; Linder, Steven H; Lembke, Anna

2016-01-01

As opioid overdose rates continue to pose a major public health crisis, the need for naloxone treatment by emergency first responders is critical. Little is known about the views of those who administer naloxone. The current study examines attitudes of health professionals on the social media platform Twitter to better understand their perceptions of opioid users, the role of naloxone, and potential training needs. Public comments on Twitter regarding naloxone were collected for a period of 3 consecutive months. The occupations of individuals who posted tweets were identified through Twitter profiles or hashtags. Categories of emergency service first responders and medical personnel were created. Qualitative analysis using a grounded theory approach was used to produce thematic content. The relationships between occupation and each theme were analyzed using Pearson chi-square statistics and post hoc analyses. A total of 368 individuals posted 467 naloxone-related tweets. Occupations consisted of professional first responders such as emergency medical technicians (EMTs), firefighters, and paramedics (n = 122); law enforcement officers (n = 70); nurses (n = 62); physicians (n = 48); other health professionals including pharmacists, pharmacy technicians, counselors, and social workers (n = 31); naloxone-trained individuals (n = 12); and students (n = 23). Primary themes included burnout, education and training, information seeking, news updates, optimism, policy and economics, stigma, and treatment. The highest levels of burnout, fatigue, and stigma regarding naloxone and opioid overdose were among nurses, EMTs, other health care providers, and physicians. In contrast, individuals who self-identified as "naloxone-trained" had the highest optimism and the lowest amount of burnout and stigma. Provider training and refinement of naloxone administration procedures are needed to improve treatment outcomes and reduce provider stigma. Social networking sites such as Twitter may have potential for offering psychoeducation to health care providers.

A multi-label learning based kernel automatic recommendation method for support vector machine.

PubMed

Zhang, Xueying; Song, Qinbao

2015-01-01

Choosing an appropriate kernel is very important and critical when classifying a new problem with Support Vector Machine. So far, more attention has been paid on constructing new kernels and choosing suitable parameter values for a specific kernel function, but less on kernel selection. Furthermore, most of current kernel selection methods focus on seeking a best kernel with the highest classification accuracy via cross-validation, they are time consuming and ignore the differences among the number of support vectors and the CPU time of SVM with different kernels. Considering the tradeoff between classification success ratio and CPU time, there may be multiple kernel functions performing equally well on the same classification problem. Aiming to automatically select those appropriate kernel functions for a given data set, we propose a multi-label learning based kernel recommendation method built on the data characteristics. For each data set, the meta-knowledge data base is first created by extracting the feature vector of data characteristics and identifying the corresponding applicable kernel set. Then the kernel recommendation model is constructed on the generated meta-knowledge data base with the multi-label classification method. Finally, the appropriate kernel functions are recommended to a new data set by the recommendation model according to the characteristics of the new data set. Extensive experiments over 132 UCI benchmark data sets, with five different types of data set characteristics, eleven typical kernels (Linear, Polynomial, Radial Basis Function, Sigmoidal function, Laplace, Multiquadric, Rational Quadratic, Spherical, Spline, Wave and Circular), and five multi-label classification methods demonstrate that, compared with the existing kernel selection methods and the most widely used RBF kernel function, SVM with the kernel function recommended by our proposed method achieved the highest classification performance.

A Multi-Label Learning Based Kernel Automatic Recommendation Method for Support Vector Machine

PubMed Central

Zhang, Xueying; Song, Qinbao

2015-01-01

Choosing an appropriate kernel is very important and critical when classifying a new problem with Support Vector Machine. So far, more attention has been paid on constructing new kernels and choosing suitable parameter values for a specific kernel function, but less on kernel selection. Furthermore, most of current kernel selection methods focus on seeking a best kernel with the highest classification accuracy via cross-validation, they are time consuming and ignore the differences among the number of support vectors and the CPU time of SVM with different kernels. Considering the tradeoff between classification success ratio and CPU time, there may be multiple kernel functions performing equally well on the same classification problem. Aiming to automatically select those appropriate kernel functions for a given data set, we propose a multi-label learning based kernel recommendation method built on the data characteristics. For each data set, the meta-knowledge data base is first created by extracting the feature vector of data characteristics and identifying the corresponding applicable kernel set. Then the kernel recommendation model is constructed on the generated meta-knowledge data base with the multi-label classification method. Finally, the appropriate kernel functions are recommended to a new data set by the recommendation model according to the characteristics of the new data set. Extensive experiments over 132 UCI benchmark data sets, with five different types of data set characteristics, eleven typical kernels (Linear, Polynomial, Radial Basis Function, Sigmoidal function, Laplace, Multiquadric, Rational Quadratic, Spherical, Spline, Wave and Circular), and five multi-label classification methods demonstrate that, compared with the existing kernel selection methods and the most widely used RBF kernel function, SVM with the kernel function recommended by our proposed method achieved the highest classification performance. PMID:25893896

Automated Cervical Screening and Triage, Based on HPV Testing and Computer-Interpreted Cytology.

PubMed

Yu, Kai; Hyun, Noorie; Fetterman, Barbara; Lorey, Thomas; Raine-Bennett, Tina R; Zhang, Han; Stamps, Robin E; Poitras, Nancy E; Wheeler, William; Befano, Brian; Gage, Julia C; Castle, Philip E; Wentzensen, Nicolas; Schiffman, Mark

2018-04-11

State-of-the-art cervical cancer prevention includes human papillomavirus (HPV) vaccination among adolescents and screening/treatment of cervical precancer (CIN3/AIS and, less strictly, CIN2) among adults. HPV testing provides sensitive detection of precancer but, to reduce overtreatment, secondary "triage" is needed to predict women at highest risk. Those with the highest-risk HPV types or abnormal cytology are commonly referred to colposcopy; however, expert cytology services are critically lacking in many regions. To permit completely automatable cervical screening/triage, we designed and validated a novel triage method, a cytologic risk score algorithm based on computer-scanned liquid-based slide features (FocalPoint, BD, Burlington, NC). We compared it with abnormal cytology in predicting precancer among 1839 women testing HPV positive (HC2, Qiagen, Germantown, MD) in 2010 at Kaiser Permanente Northern California (KPNC). Precancer outcomes were ascertained by record linkage. As additional validation, we compared the algorithm prospectively with cytology results among 243 807 women screened at KPNC (2016-2017). All statistical tests were two-sided. Among HPV-positive women, the algorithm matched the triage performance of abnormal cytology. Combined with HPV16/18/45 typing (Onclarity, BD, Sparks, MD), the automatable strategy referred 91.7% of HPV-positive CIN3/AIS cases to immediate colposcopy while deferring 38.4% of all HPV-positive women to one-year retesting (compared with 89.1% and 37.4%, respectively, for typing and cytology triage). In the 2016-2017 validation, the predicted risk scores strongly correlated with cytology (P < .001). High-quality cervical screening and triage performance is achievable using this completely automated approach. Automated technology could permit extension of high-quality cervical screening/triage coverage to currently underserved regions.

A Critical Assessment of Officially Reported Chagas Disease Surveillance Data in Mexico

PubMed Central

Shelly, Ellen M.; Acuna-Soto, Rodolfo; Ernst, Kacey C.; Sterling, Charles R.

2016-01-01

Objective Chagas disease, a disease caused by Trypanosoma cruzi, disproportionately affects poor people throughout Latin America. In Mexico, assessments of officially reported burden have not been previously reported. To evaluate discontinuity between surveillance data and data from other sources, we used data from the Mexican Ministry of Health to describe the distribution of reported Chagas disease over time in Mexico and compare it with estimates from the literature. Methods We summarized age and sex differences for Chagas cases and mortality for 1995–2013 and 1982–2010, respectively. We examined the spatial distribution of Chagas disease over time with respect to disease burden. We further compared officially reported figures with estimates from the literature. Results Among 6,494 officially reported cases, rates of Chagas disease were highest in adults aged 25–44 years (47.3%). Mortality was highest in adults aged ≥45 years (423/495, 85.5%). The data indicated increasing temporal trends for incidence and mortality. The greatest burden occurred in southern states, with increasing spatial distribution over time. Fewer than 900 cases and 40 deaths were officially reported annually, in contrast to estimates from the literature of approximately 69,000 new cases and 25,000 deaths annually. Conclusion While increasing trends in officially reported data have been observed, large discrepancies in case estimates compromise our understanding of Chagas disease epidemiology. Reported cases based on current practices are not enough to correctly assess the Chagas disease burden and spatial distribution in Mexico. Understanding the true epidemiology of this disease will lead to more focused and successful control and prevention strategies to decrease disease burden. PMID:26843671

Risk Analysis Reveals Global Hotspots for Marine Debris Ingestion by Sea Turtles

NASA Astrophysics Data System (ADS)

Schuyler, Q. A.; Wilcox, C.; Townsend, K.; Wedemeyer-Strombel, K.; Balazs, G.; van Sebille, E.; Hardesty, B. D.

2016-02-01

Plastic marine debris pollution is rapidly becoming one of the critical environmental concerns facing wildlife in the 21st century. Here we present a risk analysis for plastic ingestion by sea turtles on a global scale. We combined global marine plastic distributions based on ocean drifter data with sea turtle habitat maps to predict exposure levels to plastic pollution. Empirical data from necropsies of deceased animals were then utilised to assess the consequence of exposure to plastics. We modelled the risk (probability of debris ingestion) by incorporating exposure to debris and consequence of exposure, and included life history stage, species of sea turtle, and date of stranding observation as possible additional explanatory factors. Life history stage is the best predictor of debris ingestion, but the best-fit model also incorporates encounter rates within a limited distance from stranding location, marine debris predictions specific to the date of the stranding study, and turtle species. There was no difference in ingestion rates between stranded turtles vs. those caught as bycatch from fishing activity, suggesting that stranded animals are not a biased representation of debris ingestion rates in the background population. Oceanic life-stage sea turtles are at the highest risk of debris ingestion, and olive ridley turtles are the most at-risk species. The regions of highest risk to global sea turtle populations are off of the east coasts of the USA, Australia, and South Africa; the east Indian Ocean, and Southeast Asia. Model results can be used to predict the number of sea turtles globally at risk of debris ingestion. Based on currently available data, initial calculations indicate that up to 52% of sea turtles may have ingested debris.

Inelastic effects of Josephson junctions

NASA Astrophysics Data System (ADS)

Ranjan, Samir

We have investigated the effects of the inelastic interaction of electrons with phonons in the barrier region of S-I-S and S-N-S Josephson junctions. We find that under suitable conditions this mechanism can cause substantial modifications of the temperature dependence of the critical current jsb{c} as the inevitable loss of coherence can be more than compensated by the enhancement of the tunneling probability resulting from the phonon absorption. The effect depends strongly on the ratio qsb{TF}a of the junction width a to the screening length in the barrier region. For a S-I-S junction, a monotonic decrease in the critical current with temperature is found for qsb{TF}a ≫ 1 whereas for qsb{TF}a ≪ 1, the appearance of a peak in jsb{c}(T) near Tsb{c} is predicted. This new interesting effect is the consequence of the competition between the decrease of the superconducting gap function and the increase in the number of phonons with temperature. A wide range of parameter values has been explored and contact with relevant experimental results has been made. For an S-N-S junction, there is a large increase in the coherence length in the non-superconducting region leading to a substantial enhancement of the critical current over a wide range of temperature. It turns out that the entire temperature range can be divided broadly into two regimes. At low temperatures, the electron predominantly exchanges energy with just one phonon and it is this process that mainly determines the critical current. At higher temperatures the critical current is determined by processes in which the electrons exchange energy with many phonons during their under barrier motion.

Progress in second-generation HTS wire development and manufacturing

NASA Astrophysics Data System (ADS)

Selvamanickam, V.; Chen, Y.; Xiong, X.; Xie, Y.; Zhang, X.; Rar, A.; Martchevskii, M.; Schmidt, R.; Lenseth, K.; Herrin, J.

2008-09-01

2007 has marked yet another year of continued rapid progress in developing and manufacturing high-performance, long-length second-generation (2G) HTS wires at high speeds. Using ion beam assisted deposition (IBAD) MgO and associated buffer sputtering processes, SuperPower has now exceeded piece lengths of 1000 m of fully buffered tape reproducibly with excellent in-plane texture of 6-7 degrees and uniformity of about 2%. These kilometer lengths are produced at high speeds of about 350 m/h of 4 mm wide tape. In combination with metal organic chemical vapor deposition (MOCVD), 2G wires up to single piece lengths to 790 m with a minimum critical current value of 190 A/cm corresponding to a Critical current × Length performance of 150,100 Am have been achieved. Tape speeds up to 180 m/h have been reached MOCVD while maintaining critical currents above 200 A/cm in 100+ m lengths. Thick film MOCVD technology has been transitioned to Pilot manufacturing system where a minimum critical current of 320 A/cm has been demonstrated over a length of 155 m processed at a speed of 70 m/h in 4 mm width. Finally, nearly 10,000 m of 2G wire has been produced, exhaustively tested, and delivered to the Albany Cable project. The average minimum critical current of the wire delivered in 225 segments of 43-44 m is 70 A in 4 mm widths. A 30 m cable has been fabricated with this wire by Sumitomo Electric and has been installed in the power grid of National Grid in downtown Albany and is the world’s first 2G device installed in the grid.

Who uses firearms as a means of suicide? A population study exploring firearm accessibility and method choice

PubMed Central

Klieve, Helen; Sveticic, Jerneja; De Leo, Diego

2009-01-01

Background The 1996 Australian National Firearms Agreement introduced strict access limitations. However, reports on the effectiveness of the new legislation are conflicting. This study, accessing all cases of suicide 1997-2004, explores factors which may impact on the choice of firearms as a suicide method, including current licence possession and previous history of legal access. Methods Detailed information on all Queensland suicides (1997-2004) was obtained from the Queensland Suicide Register, with additional details of firearm licence history accessed from the Firearm Registry (Queensland Police Service). Cases were compared against licence history and method choice (firearms or other method). Odds ratios (OR) assessed the risk of firearms suicide and suicide by any method against licence history. A logistic regression was undertaken identifying factors significant in those most likely to use firearms in suicide. Results The rate of suicide using firearms in those with a current license (10.92 per 100,000) far exceeded the rate in those with no license history (1.03 per 100,000). Those with a license history had a far higher rate of suicide (30.41 per 100,000) compared to that of all suicides (15.39 per 100,000). Additionally, a history of firearms licence (current or present) was found to more than double the risk of suicide by any means (OR = 2.09, P < 0.001). The group with the highest risk of selecting firearms to suicide were older males from rural locations. Conclusion Accessibility and familiarity with firearms represent critical elements in determining the choice of method. Further licensing restrictions and the implementation of more stringent secure storage requirements are likely to reduce the overall familiarity with firearms in the community and contribute to reductions in rates of suicide. PMID:19778414

Current status and future prospects of research and development operations in traditional and complementary and alternative medicine manufacturing small- and medium-sized enterprises: a 2014 company-based survey.

PubMed

Ahn, Miyoung; Park, Eun-Ji; Woo, Jong-Min

2017-12-01

Small- and medium-sized enterprises (SMEs) have played key roles in the economic growth and technical innovation of traditional and complementary and alternative medicine (T&CM). Research and development (R&D) are critical activities for industrial progress. This study aimed to characterize the current status of SME R&D activities and to explore manufacturers' perceptions of R&D expansion. Records of the distribution of T&CM SMEs and R&D resources detailed in the 2014 Statistics of Korea T&CM Industries survey, a previously conducted survey on the industrial status of the T&CM field, were reviewed. Data on the perceptions of R&D activities were investigated through a company-based survey covering 285 T&CM-manufacturing SMEs. Greater than 99% of the 13,636 T&CM manufacturers at the time of the study were SMEs employing less than 50 workers. Natural cosmetics manufacturing SMEs (NC SMEs) had the highest R&D expenditures. NC SMEs rely heavily on internal R&D operations, which may contribute to their strong need for R&D collaboration with public research institutions and expanded T&CM-promoted R&D programs. "Digestive system disorders" are the main target diseases for current herbal and dietary supplement manufacturing SMEs and herbal medicine manufacturing SMEs. These SMEs tend to view their own product-related business as a priority for future R&D investment. This study represents the first attempt to assess SME perceptions of R&D activities. The findings herein can inform the design of sustainable programs that support R&D by reducing the gaps between the perspectives of T&CM product makers and policymakers.

Measuring outcomes in adult spinal deformity surgery: a systematic review to identify current strengths, weaknesses and gaps in patient-reported outcome measures.

PubMed

Faraj, Sayf S A; van Hooff, Miranda L; Holewijn, Roderick M; Polly, David W; Haanstra, Tsjitske M; de Kleuver, Marinus

2017-08-01

Adult spinal deformity (ASD) causes severe disability, reduces overall quality of life, and results in a substantial societal burden of disease. As healthcare is becoming more value based, and to facilitate global benchmarking, it is critical to identify and standardize patient-reported outcome measures (PROMs). This study aims to identify the current strengths, weaknesses, and gaps in PROMs used for ASD. Studies were included following a systematic search in multiple bibliographic databases between 2000 and 2015. PROMs were extracted and linked to the outcome domains of WHO's International Classification of Functioning and Health (ICF) framework. Subsequently, the clinimetric quality of identified PROMs was evaluated. The literature search identified 144 papers that met the inclusion criteria, and nine frequently used PROMs were identified. These covered 29 ICF outcome domains, which could be grouped into three of the four main ICF chapters: body function (n = 7), activity and participation (n = 19), environmental factors (n = 3), and body structure (n = 0). A low quantity (n = 3) of papers was identified that studied the clinimetric quality of PROMs. The Scoliosis Research Society (SRS)-22 has the highest level of clinimetric quality for ASD. Outcome domains related to mobility and pain were well represented. We identified a gap in current outcome measures regarding neurological and pulmonary function. In addition, no outcome domains were measured in the ICF chapter body structure. These results will serve as a foundation for the process of seeking international consensus on a standard set of outcome domains, accompanied PROMs and contributing factors to be used in future clinical trials and spine registries.

An audit on the reporting of critical results in a tertiary institute.

PubMed

Rensburg, Megan A; Nutt, Louise; Zemlin, Annalise E; Erasmus, Rajiv T

2009-03-01

Critical result reporting is a requirement for accreditation by accreditation bodies worldwide. Accurate, prompt communication of results to the clinician by the laboratory is of extreme importance. Repeating of the critical result by the recipient has been used as a means to improve the accuracy of notification. Our objective was to assess the accuracy of notification of critical chemical pathology laboratory results telephoned out to clinicians/clinical areas. We hypothesize that read-back of telephoned critical laboratory results by the recipient may improve the accuracy of the notification. This was a prospective study, where all critical results telephoned by chemical pathologists and registrars at Tygerberg Hospital were monitored for one month. The recipient was required to repeat the result (patient name, folder number and test results). Any error, as well as the designation of the recipient was logged. Of 472 outgoing telephone calls, 51 errors were detected (error rate 10.8%). Most errors were made when recording the folder number (64.7%), with incorrect patient name being the lowest (5.9%). Calls to the clinicians had the highest error rate (20%), most of them being the omission of recording folder numbers. Our audit highlights the potential errors during the post-analytical phase of laboratory testing. The importance of critical result reporting is still poorly recognized in South Africa. Implementation of a uniform accredited practice for communication of critical results can reduce error and improve patient safety.

Program Development for Primary School Teachers' Critical Thinking

ERIC Educational Resources Information Center

Boonjeam, Waraporn; Tesaputa, Kowat; Sri-ampai, Anan

2017-01-01

The objectives of this research were: 1) to study the elements and indicators of primary school teachers' critical thinking, 2) to study current situation, desirable situation, development technique, and need for developing the primary school teachers' critical thinking, 3) to develop the program for developing the primary school teachers'…

Critical Thinking Assessment across Four Sustainability-Related Experiential Learning Settings

ERIC Educational Resources Information Center

Heinrich, William F.; Habron, Geoffrey B.; Johnson, Heather L.; Goralnik, Lissy

2015-01-01

Today's complex societal problems require both critical thinking and an engaged citizenry. Current practices in higher education, such as service learning, suggest that experiential learning can serve as a vehicle to encourage students to become engaged citizens. However, critical thinking is not necessarily a part of every experiential learning…

Critical Discourse Analysis, Adult Education and "Fitba"

ERIC Educational Resources Information Center

Player, John

2013-01-01

In this article I will use an example of current adult education practice, the Glory and Dismay Football Literacies Programme (GDFLP) to appraise the value of critical discourse analysis (CDA) for adult learners, both individually and collectively, and for adult education practitioners with an interest in developing critical literacy skills. The…

Rethinking Critical Thinking

ERIC Educational Resources Information Center

Downs, Christopher J.

2008-01-01

Critical thinking is of primary importance in higher education, yet the concept remains slippery and the skill elusive. The author argues that most current critical thinking textbooks are out of line with the seminal work of John Dewey. Rather than logical argument and justification, it is suggested that carefulness, open-mindedness and creativity…

Empowering the Foreign Language Learner through Critical Literacies Development

ERIC Educational Resources Information Center

Keneman, Margaret

2016-01-01

This article examines current pedagogical trends in the foreign language classroom and argues that a critical literacies pedagogical approach (Freire, 1970) should guide instruction. A critical literacies pedagogical approach is then discussed in the context of foreign language teaching and learning, and particular attention in this article is…

Environmental Activities for Teaching Critical Thinking. [Environmental Education Information Report.

ERIC Educational Resources Information Center

Howe, Robert W.; Disinger, John F.

The ability to think critically is essential if individuals are to live, work, and function effectively in our current and changing society. The activities included in this publication were selected to identify a variety of effective strategies for teaching critical thinking skills through environmental education. Activities include library…

Transforming Violent Selves through Reflection in Critical Communicative Research

ERIC Educational Resources Information Center

Flecha, Ainhoa; Pulido, Cristina; Christou, Miranda

2011-01-01

Currently, teenagers are being socialized into a world of violent realities, not only through social interaction but also through interaction via the media, especially via the Internet. Research conducted using the critical communicative methodology has shown that this methodology helps young people to reflect critically about their violent…

A Critical Analysis of the Conceptualisation of "Coaching Philosophy"

ERIC Educational Resources Information Center

Cushion, Christopher; Partington, Mark

2016-01-01

The aim of this paper was to critically review existing literature relating to, and critically analyse current conceptualisations of, "coaching philosophy." The review reveals a bewildering approach to definitions, terms and frameworks that have limited explanation and reveal a lack of conceptual clarity. It is argued that rather than…

The Effect of Information Literacy on Teachers' Critical Thinking Disposition

ERIC Educational Resources Information Center

Saglam, Aycan Çiçek; Çankaya, Ibrahim; Üçer, Hakan; Çetin, Muhammet

2017-01-01

The concepts of information literacy and critical thinking are two important concepts of today's information and technology age closely related to each other and sometimes used interchangeably. The purpose of the current study is to explore the relationship between the secondary school teachers' critical thinking disposition and information…

Estimating the Uncertainty and Predictive Capabilities of Three-Dimensional Earth Models (Postprint)

DTIC Science & Technology

2012-03-22

www.isc.ac.uk). This global database includes more than 7,000 events whose epicentral location accuracy is known to at least 5 km. GT events with...region, which illustrates the difficulty of validating a model with travel times alone. However, the IASPEI REL database is currently the highest...S (right) paths in the IASPEI REL ground-truth database . Stations are represented by purple triangles and events by gray circles. Note the sparse

Characterization of calcium and zinc spatial distributions at the fibrocartilage zone of bone-tendon junction by synchrotron radiation-based micro X-ray fluorescence analysis combined with backscattered electron imaging

NASA Astrophysics Data System (ADS)

Lu, Hongbin; Chen, Can; Wang, Zhanwen; Qu, Jin; Xu, Daqi; Wu, Tianding; Cao, Yong; Zhou, Jingyong; Zheng, Cheng; Hu, Jianzhong

2015-09-01

Tendon attaches to bone through a functionally graded fibrocartilage zone, including uncalcified fibrocartilage (UF), tidemark (TM) and calcified fibrocartilage (CF). This transition zone plays a pivotal role in relaxing load transfer between tendon and bone, and serves as a boundary between otherwise structurally and functionally distinct tissue types. Calcium and zinc are believed to play important roles in the normal growth, mineralization, and repair of the fibrocartilage zone of bone-tendon junction (BTJ). However, spatial distributions of calcium and zinc at the fibrocartilage zone of BTJ and their distribution-function relationship are not totally understood. Thus, synchrotron radiation-based micro X-ray fluorescence analysis (SR-μXRF) in combination with backscattered electron imaging (BEI) was employed to characterize the distributions of calcium and zinc at the fibrocartilage zone of rabbit patella-patellar tendon complex (PPTC). For the first time, the unique distributions of calcium and zinc at the fibrocartilage zone of the PPTC were clearly mapped by this method. The distributions of calcium and zinc at the fibrocartilage zone of the PPTC were inhomogeneous. A significant accumulation of zinc was exhibited in the transition region between UF and CF. The highest zinc content (3.17 times of that of patellar tendon) was found in the TM of fibrocartilage zone. The calcium content began to increase near the TM and increased exponentially across the calcified fibrocartilage region towards the patella. The highest calcium content (43.14 times of that of patellar tendon) was in the transitional zone of calcified fibrocartilage region and the patella, approximately 69 μm from the location with the highest zinc content. This study indicated, for the first time, that there is a differential distribution of calcium and zinc at the fibrocartilage zone of PPTC. These observations reveal new insights into region-dependent changes across the fibrocartilage zone of BTJ and will serve as critical benchmark parameters for current efforts in BTJ repair.

Inhibitory properties of bambara groundnut protein hydrolysate and peptide fractions against angiotensin-converting enzymes, renin and free radicals.

PubMed

Arise, Abimbola K; Alashi, Adeola M; Nwachukwu, Ifeanyi D; Malomo, Sunday A; Aluko, Rotimi E; Amonsou, Eric O

2017-07-01

An increased rate of high blood pressure has led to critical human hypertensive conditions in most nations. In the present study, bambara protein hydrolysates (BPHs) obtained using three different proteases (alcalase, trypsin and pepsin) and their peptide fractions (molecular weight: 10, 5, 3 and 1 kDa) were investigated for antihypertensive and antioxidant activities. Alcalase hydrolysate contained the highest amount of low molecular weight (LMW) peptides compared to pepsin and trypsin hydrolysates. LMW peptides fractions (<1 kDa) exhibited the highest inhibitory activity against angiotensin-converting enzyme (ACE) for all the enzymes hydrolysates. For renin inhibition, alcalase hydrolysate showed the highest inhibition at 59% compared to other hydrolysates and their corresponding membrane fractions. The antioxidant power of bambara protein hydrolysates and peptide fractions was evaluated through the inhibition of linoleic acid peroxidation and ABTS scavenging activity. Among the hydrolysates, alcalase exhibited the highest inhibition of linoleic acid oxidation. Furthermore, all BPHs were able to scavenge ABTS •+ to a three-fold greater extent compared to the isolate. BPH and LMW peptide fractions could potentially serve as useful ingredients in the formulation of functional foods and nutraceuticals against high blood pressure and oxidative stress. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Performance and Reliability Analysis of Water Distribution Systems under Cascading Failures and the Identification of Crucial Pipes

PubMed Central

Shuang, Qing; Zhang, Mingyuan; Yuan, Yongbo

2014-01-01

As a mean of supplying water, Water distribution system (WDS) is one of the most important complex infrastructures. The stability and reliability are critical for urban activities. WDSs can be characterized by networks of multiple nodes (e.g. reservoirs and junctions) and interconnected by physical links (e.g. pipes). Instead of analyzing highest failure rate or highest betweenness, reliability of WDS is evaluated by introducing hydraulic analysis and cascading failures (conductive failure pattern) from complex network. The crucial pipes are identified eventually. The proposed methodology is illustrated by an example. The results show that the demand multiplier has a great influence on the peak of reliability and the persistent time of the cascading failures in its propagation in WDS. The time period when the system has the highest reliability is when the demand multiplier is less than 1. There is a threshold of tolerance parameter exists. When the tolerance parameter is less than the threshold, the time period with the highest system reliability does not meet minimum value of demand multiplier. The results indicate that the system reliability should be evaluated with the properties of WDS and the characteristics of cascading failures, so as to improve its ability of resisting disasters. PMID:24551102

Characterization of mechanical properties of hydroxyapatite-silicon-multi walled carbon nano tubes composite coatings synthesized by EPD on NiTi alloys for biomedical application.

PubMed

Khalili, Vida; Khalil-Allafi, Jafar; Sengstock, Christina; Motemani, Yahya; Paulsen, Alexander; Frenzel, Jan; Eggeler, Gunther; Köller, Manfred

2016-06-01

Release of Ni(1+) ions from NiTi alloy into tissue environment, biological response on the surface of NiTi and the allergic reaction of atopic people towards Ni are challengeable issues for biomedical application. In this study, composite coatings of hydroxyapatite-silicon multi walled carbon nano-tubes with 20wt% Silicon and 1wt% multi walled carbon nano-tubes of HA were deposited on a NiTi substrate using electrophoretic methods. The SEM images of coated samples exhibit a continuous and compact morphology for hydroxyapatite-silicon and hydroxyapatite-silicon-multi walled carbon nano-tubes coatings. Nano-indentation analysis on different locations of coatings represents the highest elastic modulus (45.8GPa) for HA-Si-MWCNTs which is between the elastic modulus of NiTi substrate (66.5GPa) and bone tissue (≈30GPa). This results in decrease of stress gradient on coating-substrate-bone interfaces during performance. The results of nano-scratch analysis show the highest critical distance of delamination (2.5mm) and normal load before failure (837mN) as well as highest critical contact pressure for hydroxyapatite-silicon-multi walled carbon nano-tubes coating. The cell culture results show that human mesenchymal stem cells are able to adhere and proliferate on the pure hydroxyapatite and composite coatings. The presence of both silicon and multi walled carbon nano-tubes (CS3) in the hydroxyapatite coating induce more adherence of viable human mesenchymal stem cells in contrast to the HA coated samples with only silicon (CS2). These results make hydroxyapatite-silicon-multi walled carbon nano-tubes a promising composite coating for future bone implant application. Copyright © 2016 Elsevier Ltd. All rights reserved.

Abundant carbon substrates drive extremely high sulfate reduction rates and methane fluxes in Prairie Pothole Wetlands.

PubMed

Dalcin Martins, Paula; Hoyt, David W; Bansal, Sheel; Mills, Christopher T; Tfaily, Malak; Tangen, Brian A; Finocchiaro, Raymond G; Johnston, Michael D; McAdams, Brandon C; Solensky, Matthew J; Smith, Garrett J; Chin, Yu-Ping; Wilkins, Michael J

2017-08-01

Inland waters are increasingly recognized as critical sites of methane emissions to the atmosphere, but the biogeochemical reactions driving such fluxes are less well understood. The Prairie Pothole Region (PPR) of North America is one of the largest wetland complexes in the world, containing millions of small, shallow wetlands. The sediment pore waters of PPR wetlands contain some of the highest concentrations of dissolved organic carbon (DOC) and sulfur species ever recorded in terrestrial aquatic environments. Using a suite of geochemical and microbiological analyses, we measured the impact of sedimentary carbon and sulfur transformations in these wetlands on methane fluxes to the atmosphere. This research represents the first study of coupled geochemistry and microbiology within the PPR and demonstrates how the conversion of abundant labile DOC pools into methane results in some of the highest fluxes of this greenhouse gas to the atmosphere ever reported. Abundant DOC and sulfate additionally supported some of the highest sulfate reduction rates ever measured in terrestrial aquatic environments, which we infer to account for a large fraction of carbon mineralization in this system. Methane accumulations in zones of active sulfate reduction may be due to either the transport of free methane gas from deeper locations or the co-occurrence of methanogenesis and sulfate reduction. If both respiratory processes are concurrent, any competitive inhibition of methanogenesis by sulfate-reducing bacteria may be lessened by the presence of large labile DOC pools that yield noncompetitive substrates such as methanol. Our results reveal some of the underlying mechanisms that make PPR wetlands biogeochemical hotspots, which ultimately leads to their critical, but poorly recognized role in regional greenhouse gas emissions. © 2017 John Wiley & Sons Ltd.

Abundant carbon substrates drive extremely high sulfate reduction rates and methane fluxes in Prairie Pothole Wetlands

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

Dalcin Martins, Paula; Hoyt, David W.; Bansal, Sheel

Inland waters are increasingly recognized as critical sites of methane emissions to the atmosphere, but the biogeochemical reactions driving such fluxes are less well understood. The Prairie Pothole Region (PPR) of North America is one of the largest wetland complexes in the world, containing millions of small, shallow wetlands. The sediment pore waters of PPR wetlands contain some of the highest concentrations of dissolved organic carbon (DOC) and sulfur species ever recorded in terrestrial aquatic environments. Using a suite of geochemical and microbiological analyses we measured the impact of sedimentary carbon and sulfur transformations in these wetlands on methane fluxesmore » to the atmosphere. This research represents the first study of coupled geochemistry and microbiology within the PPR, and demonstrates how the conversion of abundant labile DOC pools into methane results in some of the highest fluxes of this greenhouse gas to the atmosphere ever reported. Abundant DOC and sulfate additionally supported some of the highest sulfate reduction rates ever measured in terrestrial aquatic environments, which we infer to account for a large fraction of carbon mineralization in this system. Methane accumulations in zones of active sulfate reduction may be due to either the transport of free methane gas from deeper locations, or the co-occurrence of methanogenesis and sulfate reduction. If both respiratory processes are concurrent, any competitive inhibition of methanogenesis by sulfate-reducing bacteria may be lessened by the presence of large labile DOC pools that yield non-competitive substrates such as methanol. Our results reveal some of the underlying mechanisms that make PPR wetlands biogeochemical hotspots, which ultimately leads to their critical, but poorly recognized role in regional greenhouse gas emissions.« less

Abundant carbon substrates drive extremely high sulfate reduction rates and methane fluxes in Prairie Pothole Wetlands

USGS Publications Warehouse

Martins, Paula; Hoyt, David W.; Bansal, Sheel; Mills, Christopher T.; Tfaily, Malak; Tangen, Brian; Finocchiaro, Raymond; Johnston, Michael D.; McAdams, Brandon C.; Solensky, Matthew J.; Smith, Garrett J.; Chin, Yu-Ping; Wilkins, Michael J.

2017-01-01

Inland waters are increasingly recognized as critical sites of methane emissions to the atmosphere, but the biogeochemical reactions driving such fluxes are less well understood. The Prairie Pothole Region (PPR) of North America is one of the largest wetland complexes in the world, containing millions of small, shallow wetlands. The sediment pore waters of PPR wetlands contain some of the highest concentrations of dissolved organic carbon (DOC) and sulfur species ever recorded in terrestrial aquatic environments. Using a suite of geochemical and microbiological analyses, we measured the impact of sedimentary carbon and sulfur transformations in these wetlands on methane fluxes to the atmosphere. This research represents the first study of coupled geochemistry and microbiology within the PPR and demonstrates how the conversion of abundant labile DOC pools into methane results in some of the highest fluxes of this greenhouse gas to the atmosphere ever reported. Abundant DOC and sulfate additionally supported some of the highest sulfate reduction rates ever measured in terrestrial aquatic environments, which we infer to account for a large fraction of carbon mineralization in this system. Methane accumulations in zones of active sulfate reduction may be due to either the transport of free methane gas from deeper locations or the co-occurrence of methanogenesis and sulfate reduction. If both respiratory processes are concurrent, any competitive inhibition of methanogenesis by sulfate-reducing bacteria may be lessened by the presence of large labile DOC pools that yield noncompetitive substrates such as methanol. Our results reveal some of the underlying mechanisms that make PPR wetlands biogeochemical hotspots, which ultimately leads to their critical, but poorly recognized role in regional greenhouse gas emissions.

Climate change impacts on forest soil critical acid loads and exceedances at a national scale

Treesearch

Steven G. McNulty; Erika C. Cohen; Jennifer A. Moore Myers

2013-01-01

Federal agencies are currently developing guidelines for forest soil critical acid loads across the United States. A critical acid load is defined as the amount of acid deposition (usually expressed on an annual basis) that an ecosystem can absorb. Traditionally, an ecosystem is considered to be at risk for health impairment when the critical acid load exceeds a level...

A Critical Co-Constructed Autoethnography of a Gendered Cross-Cultural Mentoring between Two Early Career Latin@ Scholars Working in the Deep South

ERIC Educational Resources Information Center

Suriel, Regina L.; Martinez, James; Evans-Winters, Venus

2018-01-01

Multicultural mentoring has been suggested to support Latin@ faculty success in their careers, yet current literature on effective mentorships of Latin@ faculty is limited. This critical co-constructed autoethnography draws on critical race theory (CRT) and latin@ critical race theory (LatCrit) frameworks to highlight the lived experiences and key…

Scientific publications in critical care medicine journals from Chinese authors: a 10-year survey of the literature.

PubMed

Li, Zhi; Liao, Zhuan; Wu, Fei-Xiang; Yang, Li-Qun; Sun, Yu-Ming; Yu, Wei-Feng

2010-10-01

People of Chinese ethnicity are the largest population in the world. Critical care medicine in China is developing rapidly and has achieved great advances in recent 20 years. The research contribution in critical care medicine among Chinese individuals in the three major regions of China--Mainland (ML), Hong Kong (HK), and Taiwan (TW)--is unknown. Articles published in 18 journals on critical care medicine originating from ML, TW, and HK from 1999 to 2008 were retrieved from the PubMed database and Science Citation Index Expanded. Quantity and quality analyses were conducted for the total numbers of articles, clinical trials, randomized controlled trials, impact factors (IF), citations, and articles published in high-impact journals. There were 932 articles from ML (268), TW (506), and HK (158) from 1999 to 2008. The annual total numbers of articles of the three regions increased gradually from 1999 to 2008 (from 57 to 157). From 2002 onward, the number of articles published from ML exceeded that from HK, but TW still has the dominance in both annual and total number of articles published compared with ML and HK. The accumulated IF of articles from TW (1676.67) was higher than that from ML (708.25) and HK (449.51). TW had the highest average IF of 3.31 followed by HK of 2.85 and ML of 2.64. HK had the highest average citations of each article of 10.73, followed by TW of 6.74 and ML of 5.34. The Journal of Trauma was the most popular journal in the three regions. The total numbers of articles in China increased markedly from 1999 to 2008. TW published the most number of articles, clinical trials, and randomised controlled trials among the three regions. The Journal of Trauma was the most popular journal in the three regions.

The safer clinical systems project in renal care.

PubMed

Weale, Andy R

2013-09-01

Current systems in place in healthcare are designed to detect harm after it has happened (e.g critical incident reports) and make recommendations based on an assessment of that event. Safer Clinical Systems, a Health Foundation funded project, is designed to proactively search for risk within systems, rather than being reactive to harm. The aim of the Safer Clinical Systems project in Renal Care was to reduce the risks associated with shared care for patients who are undergoing surgery but are looked after peri-operatively by nephrology teams on nephrology wards. This report details our findings of the diagnostic phase of Safer Clinical Systems: the proactive search for risk. We have evaluated the current system of care using a set of risk evaluation and process mapping tools (Failure Modes and Effects Analysis (FMEA) and Hierarchical Task Analysis HTA). We have engaged staff with the process mapping and risk assessment tools. We now understand our system and understand where the highest risk tasks are undertaken during a renal in-patient stay during which a patient has an operation. These key tasks occur across the perioperaive period and are not confined to one aspect of care. A measurement strategy and intervention plan have been designed around these tasks. Safer Clinical Systems has identified high risk, low reliability tasks in our system. We look forward to fully reporting these data in 2014. © 2013 European Dialysis and Transplant Nurses Association/European Renal Care Association.

Harnessing Scientific and Technological Advances to Improve Equity in Kidney Allocation Policies.

PubMed

Tambur, A R; Audry, B; Antoine, C; Suberbielle, C; Glotz, D; Jacquelinet, C

2017-12-01

We reported that current assignment of HLA-DQ is a barrier to organ allocation. Here we simulated the impact of incorporating HLA-DQ antigens and antibodies as A/B and αβ allelic variants, respectively, on calculated panel reactive antibody (cPRA) and probability of finding potential compatible donors (PCD). A cohort of 1224 donors and 2075 sensitized candidates was analyzed using HLA-DQαβ allelic (study) versus serologic (current practice) nomenclature. A significant (p < 10 -4 ) decrease in cPRA was observed with higher impact for male versus female, and first transplant versus retransplant (p < 10 -4 ), affecting mostly patients with moderate cPRA (30-80%). Consequently, the number of patients qualifying for 100% cPRA points according to the United Network for Organ Sharing-Kidney Allocation System decreased by 37%. More critically, by using allelic versus serologic nomenclature for HLA-DQ, the number of PCDs for all patients was increased, with male and first-transplant patients showing a higher expansion compared with female and retransplants. Patients of blood group O showed the highest benefit. The goal of reporting unacceptable antigens is to improve accuracy of virtual crossmatching and increase the likelihood of finding immunologically compatible donors. Our simulation provides strong support for the need to re-evaluate the use of allele typing and how HLA-DQ antigens and antibodies are incorporated into allocation policies to ensure equity. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Joint analysis of stressors and ecosystem services to enhance restoration effectiveness.

PubMed

Allan, J David; McIntyre, Peter B; Smith, Sigrid D P; Halpern, Benjamin S; Boyer, Gregory L; Buchsbaum, Andy; Burton, G A; Campbell, Linda M; Chadderton, W Lindsay; Ciborowski, Jan J H; Doran, Patrick J; Eder, Tim; Infante, Dana M; Johnson, Lucinda B; Joseph, Christine A; Marino, Adrienne L; Prusevich, Alexander; Read, Jennifer G; Rose, Joan B; Rutherford, Edward S; Sowa, Scott P; Steinman, Alan D

2013-01-02

With increasing pressure placed on natural systems by growing human populations, both scientists and resource managers need a better understanding of the relationships between cumulative stress from human activities and valued ecosystem services. Societies often seek to mitigate threats to these services through large-scale, costly restoration projects, such as the over one billion dollar Great Lakes Restoration Initiative currently underway. To help inform these efforts, we merged high-resolution spatial analyses of environmental stressors with mapping of ecosystem services for all five Great Lakes. Cumulative ecosystem stress is highest in near-shore habitats, but also extends offshore in Lakes Erie, Ontario, and Michigan. Variation in cumulative stress is driven largely by spatial concordance among multiple stressors, indicating the importance of considering all stressors when planning restoration activities. In addition, highly stressed areas reflect numerous different combinations of stressors rather than a single suite of problems, suggesting that a detailed understanding of the stressors needing alleviation could improve restoration planning. We also find that many important areas for fisheries and recreation are subject to high stress, indicating that ecosystem degradation could be threatening key services. Current restoration efforts have targeted high-stress sites almost exclusively, but generally without knowledge of the full range of stressors affecting these locations or differences among sites in service provisioning. Our results demonstrate that joint spatial analysis of stressors and ecosystem services can provide a critical foundation for maximizing social and ecological benefits from restoration investments.

Current Cigarette Smoking Among Adults - United States, 2016.

PubMed

Jamal, Ahmed; Phillips, Elyse; Gentzke, Andrea S; Homa, David M; Babb, Stephen D; King, Brian A; Neff, Linda J

2018-01-19

The U.S. Surgeon General has concluded that the burden of death and disease from tobacco use in the United States is overwhelmingly caused by cigarettes and other combusted tobacco products (1). Cigarettes are the most commonly used tobacco product among U.S. adults, and about 480,000 U.S. deaths per year are caused by cigarette smoking and secondhand smoke exposure (1). To assess progress toward the Healthy People 2020 target of reducing the proportion of U.S. adults aged ≥18 years who smoke cigarettes to ≤12.0% (objective TU-1.1),* CDC analyzed data from the 2016 National Health Interview Survey (NHIS). In 2016, the prevalence of current cigarette smoking among adults was 15.5%, which was a significant decline from 2005 (20.9%); however, no significant change has occurred since 2015 (15.1%). In 2016, the prevalence of cigarette smoking was higher among adults who were male, aged 25-64 years, American Indian/Alaska Native or multiracial, had a General Education Development (GED) certificate, lived below the federal poverty level, lived in the Midwest or South, were uninsured or insured through Medicaid, had a disability/limitation, were lesbian, gay, or bisexual (LGB), or had serious psychological distress. During 2005-2016, the percentage of ever smokers who quit smoking increased from 50.8% to 59.0%. Proven population-based interventions are critical to reducing the health and economic burden of smoking-related diseases among U.S. adults, particularly among subpopulations with the highest smoking prevalences (1,2).

Risks for depression onset in primary care elderly patients: potential targets for preventive interventions.

PubMed

Lyness, Jeffrey M; Yu, Qin; Tang, Wan; Tu, Xin; Conwell, Yeates

2009-12-01

Prevention of late-life depression, a common, disabling condition with often poor outcomes in primary care, requires identification of seniors at highest risk of incident episodes. The authors examined a broad range of clinical, functional, and psychosocial predictors of incident depressive episodes in a well-characterized cohort of older primary care patients. In this observational cohort study, patients age >/=65 years without current major depression, recruited from practices in general internal medicine, geriatrics, and family medicine, received annual follow-up assessments over a period of 1 to 4 years. Of 617 enrolled subjects, 405 completed the 1-year follow-up evaluation. The Structured Clinical Interview for DSM-IV (SCID) determined incident major depressive episodes. Each risk indicator's predictive utility was examined by calculating the risk exposure rate, incident risk ratio, and population attributable fraction, leading to determination of the number needed to treat in order to prevent incident depression. A combination of risks, including minor or subsyndromal depression, impaired functional status, and history of major or minor depression, identified a group in which fully effective treatment of five individuals would prevent one new case of incident depression. Indicators routinely assessed in primary care identified a group at very high risk for onset of major depressive episodes. Such markers may inform current clinical care by fostering the early detection and intervention critical to improving patient outcomes and may serve as the basis for future studies refining the recommendations for screening and determining the effectiveness of preventive interventions.

Joint analysis of stressors and ecosystem services to enhance restoration effectiveness

PubMed Central

Allan, J. David; McIntyre, Peter B.; Smith, Sigrid D. P.; Halpern, Benjamin S.; Boyer, Gregory L.; Buchsbaum, Andy; Burton, G. A.; Campbell, Linda M.; Chadderton, W. Lindsay; Ciborowski, Jan J. H.; Doran, Patrick J.; Eder, Tim; Infante, Dana M.; Johnson, Lucinda B.; Joseph, Christine A.; Marino, Adrienne L.; Prusevich, Alexander; Read, Jennifer G.; Rose, Joan B.; Rutherford, Edward S.; Sowa, Scott P.; Steinman, Alan D.

2013-01-01

With increasing pressure placed on natural systems by growing human populations, both scientists and resource managers need a better understanding of the relationships between cumulative stress from human activities and valued ecosystem services. Societies often seek to mitigate threats to these services through large-scale, costly restoration projects, such as the over one billion dollar Great Lakes Restoration Initiative currently underway. To help inform these efforts, we merged high-resolution spatial analyses of environmental stressors with mapping of ecosystem services for all five Great Lakes. Cumulative ecosystem stress is highest in near-shore habitats, but also extends offshore in Lakes Erie, Ontario, and Michigan. Variation in cumulative stress is driven largely by spatial concordance among multiple stressors, indicating the importance of considering all stressors when planning restoration activities. In addition, highly stressed areas reflect numerous different combinations of stressors rather than a single suite of problems, suggesting that a detailed understanding of the stressors needing alleviation could improve restoration planning. We also find that many important areas for fisheries and recreation are subject to high stress, indicating that ecosystem degradation could be threatening key services. Current restoration efforts have targeted high-stress sites almost exclusively, but generally without knowledge of the full range of stressors affecting these locations or differences among sites in service provisioning. Our results demonstrate that joint spatial analysis of stressors and ecosystem services can provide a critical foundation for maximizing social and ecological benefits from restoration investments. PMID:23248308