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Sample records for bio-diesel initiatives potential

  1. Life Cycle Assessment of Bio-diesel Production—A Comparative Analysis

    NASA Astrophysics Data System (ADS)

    Chatterjee, R.; Sharma, V.; Mukherjee, S.; Kumar, S.

    2014-04-01

    This work deals with the comparative analysis of environmental impacts of bio-diesel produced from Jatropha curcas, Rapeseed and Palm oil by applying the life cycle assessment and eco-efficiency concepts. The environmental impact indicators considered in the present paper include global warming potential (GWP, CO2 equivalent), acidification potential (AP, SO2 equivalent) and eutrophication potential (EP, NO3 equivalent). Different weighting techniques have been used to present and evaluate the environmental characteristics of bio-diesel. With the assistance of normalization values, the eco-efficiency was demonstrated in this work. The results indicate that the energy consumption of bio-diesel production is lowest in Jatropha while AP and EP are more in case of Jatropha than that of Rapeseed and Palm oil.

  2. Performance Evaluation of Diesel Engine with Preheated Bio Diesel with Additives

    NASA Astrophysics Data System (ADS)

    Ram Vajja, Sai; Murali, R. B. V.

    2016-09-01

    This paper mainly reviews about the usage of preheated bio diesel added with 0.5% Etchant as an alternative fuel and evaluates its performance for various blends with different loads. Bio diesel is added with Etchant for rapid combustion as for the bio diesel, the cetane number is high that results in shorter delay of ignition and the mixture is preheated to raise its temperature to improve the combustion process. Analysis of the parameters required to define the combustion characteristics such as IP, BP, ηbth, ηm, ISFC, BSFC, IMEP, MFC, Exhaust Gas Temperature, Heat Release and heat balance is necessary as these values are significant to assess the performance of engine and its emissions of preheated bio diesel.

  3. Optimization of bio-diesel production from soybean and wastes of cooked oil: combining dielectric microwave irradiation and a SrO catalyst.

    PubMed

    Koberg, Miri; Abu-Much, Riam; Gedanken, Aharon

    2011-01-01

    This work offers an optimized method in the transesterification of pristine (soybean) oil and cooked oil to bio-diesel, based on microwave dielectric irradiation as a driving force for the transesterification reaction and SrO as a catalyst. This combination has demonstrated excellent catalytic activity and stability. The transesterification was carried out with and without stirring. According to 1H NMR spectroscopy and TLC results, this combination accelerates the reaction (to less than 60 s), maintaining a very high conversion (99%) and high efficiency. The catalytic activity of SrO under atmospheric pressure in the presence of air and under the argon atmosphere is demonstrated. The optimum conversion of cooked oil (99.8%) is achieved under MW irradiation of 1100 W output with magnetic stirring after only 10 s. The optimum method decreases the cost of bio-diesel production and has the potential for industrial application in the transesterification of cooked oil to bio-diesel. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Bio-diesel production directly from the microalgae biomass of Nannochloropsis by microwave and ultrasound radiation.

    PubMed

    Koberg, Miri; Cohen, Moshe; Ben-Amotz, Ami; Gedanken, Aharon

    2011-03-01

    This work offers an optimized method for the direct conversion of harvested Nannochloropsis algae into bio-diesel using two novel techniques. The first is a unique bio-technology-based environmental system utilizing flue gas from coal burning power stations for microalgae cultivation. This method reduces considerably the cost of algae production. The second technique is the direct transesterification (a one-stage method) of the Nannochloropsis biomass to bio-diesel production using microwave and ultrasound radiation with the aid of a SrO catalyst. These two techniques were tested and compared to identify the most effective bio-diesel production method. Based on our results, it is concluded that the microwave oven method appears to be the most simple and efficient method for the one-stage direct transesterification of the as-harvested Nannochloropsis algae. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Storage Tanks and Dispensers for E85 and Bio-Diesel

    SciTech Connect

    Webster, Michael; Frederick, Justin

    2014-02-10

    Project objective is to improve the District's alternative fueling infrastructure by installing storage tanks and dispensers for E-85 and Bio-Diesel at the existing Blackwell Forest Preserve Alternative Fuel Station. The addition of E-85 and Bio-Diesel at this station will continue to reduce our dependency on foreign oil, while promoting the use of clean burning, domestically produced, renewable alternative fuels. In addition, this station will promote strong intergovernmental cooperation as other governmental agencies have expressed interest in utilizing this station.

  6. Development of a Laminar Flame Test Facility for Bio-Diesel Characterization

    DTIC Science & Technology

    2009-12-01

    CURRENT TESTING STANDARD FOR BIO-FUEL Oil companies and vehicle manufacturers are actively working with biofuel extender producers to obtain agreement on...the transesterified product. Due to incomplete combustion, fuels with low cetane numbers show an increase in emissions. Palm Oil and Tallow-derived...LIST OF TABLES Table 1.  Testing Standards for Bio-Diesel (Extracted from Biofuel Systems Group: www.biofuelsystems.com/biodiesel/specification

  7. [Determination of lead in microemulsified rapeseed oil and bio-diesel oil by GFAAS].

    PubMed

    Li, Sheng-qing; He, Xiao-min; Du, Ping; Wang, Min; Chen, Hao; Wu, Mou-cheng

    2008-10-01

    Bio-diesel oil has attracted much attention as a substitutable energy sources for its renewable and eco-friendly property. However, problems of lead contamination in fuel are also emphasized increasingly at present. So it was of quite significance to determine the contents of lead in bio-diesel oil and its raw material rapeseed oil. An effective method was developed for the rapid determination of lead in rapeseed oil and bio-diesel oil by graphite furnace atomic absorption spectrometry (GFAAS) after their stabilization as microemulsions. In this research work, polyethyleneglycol octyl phenyl ether and n-butanol were used for emulsifier and auxiliary emulsifying agent, respectively. For Pb, efficient thermal stabilization was obtained using NH4H2PO4 as matrix modifier. Sample stabilization was necessary because of evident analyte losses that occurred immediately after sampling. Excellent long-term sample stabilization and the influence of the microemulsion composition on the GFAAS response were observed by mixing different organic solvents. The ashing and atomization temperature and ramp rate influenced the sensitivity obtained for Ph. Take this into account, the optimum conditions of the graphite furnace atomic absorption spectrometric determination of Pb in rapeseed oil and bio-diesel oil samples were investigated. The results showed that the microemulsion was quite stable when the value of V(20% polyethyleneglycol octyl phenyl ether), V(n-butanol), V(oil) and V(water) was 0.1: 8.9: 0.5: 0.5, without matrix interference effect. The determination limit of the proposed method was 126.2 microg x L(-1) for Pb, comfortably below the values found in the analyzed samples. The recoveries were from 81.8% to 109.0%, which performed using the addition of different concentrations of lead to bio-diesel oil, rapeseed oil and petrochemical diesel samples. The relative standard deviation of determination was 5.84%. This work showed the great efficiency of the microemulsion

  8. Experimental assessment of toxic phytochemicals in Jatropha curcas: oil, cake, bio-diesel and glycerol.

    PubMed

    Pradhan, Subhalaxmi; Naik, S N; Khan, M Ashhar I; Sahoo, P K

    2012-02-01

    Jatropha curcas seed is a rich source of oil; however, it can not be utilised for nutritional purposes due to presence of toxic and anti-nutritive compounds. The main objective of the present study was to quantify the toxic phytochemicals present in Indian J. curcas (oil, cake, bio-diesel and glycerol). The amount of phorbol esters is greater in solvent extracted oil (2.8 g kg⁻¹) than in expeller oil (2.1 g kg⁻¹). Liquid chromatography-mass spectroscopy analysis of the purified compound from an active extract of oil confirmed the presence of phorbol esters. Similarly, the phorbol esters content is greater in solvent extracted cake (1.1 g kg⁻¹) than in cake after being expelled (0.8 g kg⁻¹). The phytate and trypsin inhibitory activity of the cake was found to be 98 g kg⁻¹ and 8347 TIU g⁻¹ of cake, respectively. Identification of curcin was achieved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the concentration of curcin was 0.95 g L⁻¹ of crude concentrate obtained from cake. Higher amounts of phorbol esters are present in oil than cake but bio-diesel and glycerol are free of phorbol esters. The other anti-nutritional components such as trypsin inhibitors, phytates and curcin are present in cake, so the cake should be detoxified before being used for animal feed. Copyright © 2011 Society of Chemical Industry.

  9. Sustainable Energy Production from Jatropha Bio-Diesel

    NASA Astrophysics Data System (ADS)

    Yadav, Amit Kumar; Krishna, Vijai

    2012-10-01

    The demand for petroleum has risen rapidly due to increasing industrialization and modernization of the world. This economic development has led to a huge demand for energy, where the major part of that energy is derived from fossil sources such as petroleum, coal and natural gas. Continued use of petroleum sourced fuels is now widely recognized as unsustainable because of depleting supplies. There is a growing interest in using Jatropha curcas L. oil as the feedstock for biodiesel production because it is non-edible and thus does not compromise the edible oils, which are mainly used for food consumption. Further, J. curcas L. seed has a high content of free fatty acids that is converted in to biodiesel by trans esterification with alcohol in the presence of a catalyst. The biodiesel produced has similar properties to that of petroleum-based diesel. Biodiesel fuel has better properties than petro diesel fuel; it is renewable, biodegradable, non-toxic, and essentially free of sulfur and aromatics. Biodiesel seems to be a realistic fuel for future. Biodiesel has the potential to economically, socially, and environmentally benefit communities as well as countries, and to contribute toward their sustainable development.

  10. DSC studies to evaluate the impact of bio-oil on cold flow properties and oxidation stability of bio-diesel.

    PubMed

    Garcia-Perez, Manuel; Adams, Thomas T; Goodrum, John W; Das, K C; Geller, Daniel P

    2010-08-01

    This paper describes the use of Differential Scanning Calorimetry (DSC) to evaluate the impact of varying mix ratios of bio-oil (pyrolysis oil) and bio-diesel on the oxidation stability and on some cold flow properties of resulting blends. The bio-oils employed were produced from the semi-continuous Auger pyrolysis of pine pellets and the batch pyrolysis of pine chips. The bio-diesel studied was obtained from poultry fat. The conditions used to prepare the bio-oil/bio-diesel blends as well as some of the fuel properties of these blends are reported. The experimental results suggest that the addition of bio-oil improves the oxidation stability of the resulting blends and modifies the crystallization behavior of unsaturated compounds. Upon the addition of bio-oil an increase in the oxidation onset temperature, as determined by DSC, was observed. The increase in bio-diesel oxidation stability is likely to be due to the presence of hindered phenols abundant in bio-oils. A relatively small reduction in DSC characteristic temperatures which are associated with cold flow properties was also observed but can likely be explained by a dilution effect.

  11. Construction of combustion models for rapeseed methyl ester bio-diesel fuel for internal combustion engine applications.

    PubMed

    Golovitchev, Valeri I; Yang, Junfeng

    2009-01-01

    Bio-diesel fuels are non-petroleum-based diesel fuels consisting of long chain alkyl esters produced by the transesterification of vegetable oils, that are intended for use (neat or blended with conventional fuels) in unmodified diesel engines. There have been few reports of studies proposing theoretical models for bio-diesel combustion simulations. In this study, we developed combustion models based on ones developed previously. We compiled the liquid fuel properties, and the existing detailed mechanism of methyl butanoate ester (MB, C(5)H(10)O(2)) oxidation was supplemented by sub-mechanisms for two proposed fuel constituent components, C(7)H(16) and C(7)H(8)O (and then, by mp2d, C(4)H(6)O(2) and propyne, C(3)H(4)) to represent the combustion model for rapeseed methyl ester described by the chemical formula, C(19)H(34)O(2) (or C(19)H(36)O(2)). The main fuel vapor thermal properties were taken as those of methyl palmitate C(19)H(36)O(2) in the NASA polynomial form of the Burcat database. The special global reaction was introduced to "crack" the main fuel into its constituent components. This general reaction included 309 species and 1472 reactions, including soot and NO(x) formation processes. The detailed combustion mechanism was validated using shock-tube ignition-delay data under diesel engine conditions. For constant volume and diesel engine (Volvo D12C) combustion modeling, this mechanism could be reduced to 88 species participating in 363 reactions.

  12. Investigation of Bio-Diesel Fueled Engines under Low-Temperature Combustion Strategies

    SciTech Connect

    Chia-fon F. Lee; Alan C. Hansen

    2010-09-30

    In accordance with meeting DOE technical targets this research was aimed at developing and optimizing new fuel injection technologies and strategies for the combustion of clean burning renewable fuels in diesel engines. In addition a simultaneous minimum 20% improvement in fuel economy was targeted with the aid of this novel advanced combustion system. Biodiesel and other renewable fuels have unique properties that can be leveraged to reduce emissions and increase engine efficiency. This research is an investigation into the combustion characteristics of biodiesel and its impacts on the performance of a Low Temperature Combustion (LTC) engine, which is a novel engine configuration that incorporates technologies and strategies for simultaneously reducing NOx and particulate emissions while increasing engine efficiency. Generating fundamental knowledge about the properties of biodiesel and blends with petroleum-derived diesel and their impact on in-cylinder fuel atomization and combustion processes was an important initial step to being able to optimize fuel injection strategies as well as introduce new technologies. With the benefit of this knowledge experiments were performed on both optical and metal LTC engines in which combustion and emissions could be observed and measured under realistic conditions. With the aid these experiments and detailed combustion models strategies were identified and applied in order to improve fuel economy and simultaneously reduce emissions.

  13. Effects of Alumina Nano Metal Oxide Blended Palm Stearin Methyl Ester Bio-Diesel on Direct Injection Diesel Engine Performance and Emissions

    NASA Astrophysics Data System (ADS)

    Krishna, K.; Kumar, B. Sudheer Prem; Reddy, K. Vijaya Kumar; Charan Kumar, S.; Kumar, K. Ravi

    2017-08-01

    The Present Investigation was carried out to study the effect of Alumina Metal Oxide (Al2O3) Nano Particles as additive for Palm Stearin Methyl Ester Biodiesel (B 100) and their blends as an alternate fuel in four stroke single cylinder water cooled, direct injection diesel engine. Alumina Nano Particles has high calorific value and relatively high thermal conductivity (30‑1 W m K‑1) compare to diesel, which helps to promote more combustion in engines due to their higher thermal efficiency. In the experimentation Al2O3 were doped in various proportions with the Palm Stearin Methyl Ester Biodiesel (B-100) using an ultrasonicator and a homogenizer with cetyl trimethyl ammonium bromide (CTAB) as the cationic surfactant. The test were performed on a Kirsloskar DI diesel engine at constant speed of 1500 rpm using different Nano Biodiesel Fuel blends (psme+50 ppm, psme+150 ppm, and psme+200 ppm) and results were compared with those of neat conventional diesel and Palm Stearin Methyl Ester Bio diesel. It was observed that for Nano Biodiesel Fuel blend (psme+50ppm) there is an significant reduction in carbon monoxide (CO) emissions and Nox emissions compared to diesel and the brake thermal efficiency for (psme+50ppm) was almost same as diesel.

  14. Performance and emission characteristics of a low heat rejection engine with different air gap thicknesses with Jatropha oil based bio-diesel.

    PubMed

    Murali Krishna, M V S; Sarita, G; Seshagiri Rao, V V R; Chowdary, R P; Ramana Reddy, Ch V

    2010-04-01

    The research work on alternate fuels has been the topic of wider interest in the context of depletion of fossil fuels and increasing of pollution levels of the engines with conventional fossil fuels. Alcohols and vegetable oils are considered to replace diesel fuels as they are renewable in nature. However, use of alcohols in internal combustion engines is limited in India, as these fuels are diverted to PetroChemical industries and hence much emphasis is given to the non-edible vegetable oils as alternate fuels in internal combustion engines. However, the drawbacks of low volatility and high viscosity associated with non-edible vegetable oils call for hot combustion chamber, provided by low heat rejection (LHR) diesel engine. Investigations are carried out on a LHR diesel engine with varied air gap thicknesses and injection pressures with jatropha oil based bio-diesel at normal temperature. Performance is improved with high degree of insulation with LHR engine with vegetable oil in comparison with conventional engine (CE) with pure diesel operation.

  15. Action Potential Initiation in Neocortical Inhibitory Interneurons

    PubMed Central

    Li, Tun; Tian, Cuiping; Scalmani, Paolo; Frassoni, Carolina; Mantegazza, Massimo; Wang, Yonghong; Yang, Mingpo; Wu, Si; Shu, Yousheng

    2014-01-01

    Action potential (AP) generation in inhibitory interneurons is critical for cortical excitation-inhibition balance and information processing. However, it remains unclear what determines AP initiation in different interneurons. We focused on two predominant interneuron types in neocortex: parvalbumin (PV)- and somatostatin (SST)-expressing neurons. Patch-clamp recording from mouse prefrontal cortical slices showed that axonal but not somatic Na+ channels exhibit different voltage-dependent properties. The minimal activation voltage of axonal channels in SST was substantially higher (∼7 mV) than in PV cells, consistent with differences in AP thresholds. A more mixed distribution of high- and low-threshold channel subtypes at the axon initial segment (AIS) of SST cells may lead to these differences. Surprisingly, NaV1.2 was found accumulated at AIS of SST but not PV cells; reducing NaV1.2-mediated currents in interneurons promoted recurrent network activity. Together, our results reveal the molecular identity of axonal Na+ channels in interneurons and their contribution to AP generation and regulation of network activity. PMID:25203314

  16. Comparative mutagenicity and genotoxicity of particles and aerosols emitted by the combustion of standard vs. rapeseed methyl ester supplemented bio-diesel fuels: impact of after treatment devices: oxidation catalyst and particulate filter.

    PubMed

    André, V; Barraud, C; Capron, D; Preterre, D; Keravec, V; Vendeville, C; Cazier, F; Pottier, D; Morin, J P; Sichel, F

    2015-01-01

    Diesel exhausts are partly responsible for the deleterious effects on human health associated with urban pollution, including cardiovascular diseases, asthma, COPD, and possibly lung cancer. Particulate fraction has been incriminated and thus largely investigated for its genotoxic properties, based on exposure conditions that are, however, not relevant for human risk assessment. In this paper, original and more realistic protocols were used to investigate the hazards induced by exhausts emitted by the combustion of standard (DF0) vs. bio-diesel fuels (DF7 and DF30) and to assess the impact of exhaust treatment devices (DOC and DPF). Mutagenicity and genotoxicity were evaluated for (1) resuspended particles ("off line" exposure that takes into account the bioavailability of adsorbed chemicals) and for (2) the whole aerosols (particles+gas phase components) under continuous flow exposure ("on line" exposure). Native particles displayed mutagenic properties associated with nitroaromatic profiles (YG1041), whereas PAHs did not seem to be involved. After DOC treatment, the mutagenicity of particles was fully abolished. In contrast, the level of particle deposition was low under continuous flow exposure, and the observed mutagenicity in TA98 and TA102 was thus attributable to the gas phase. A bactericidal effect was also observed in TA102 after DOC treatment, and a weak but significant mutagenicity persisted after DPF treatment for bio-diesel fuels. No formation of bulky DNA-adducts was observed on A549 cells exposed to diesel exhaust, even in very drastic conditions (organic extracts corresponding to 500 μg equivalent particule/mL, 48 h exposure). Taken together, these data indicate that the exhausts issued from the bio-diesel fuels supplemented with rapseed methyl ester (RME), and generated by current diesel engines equipped with after treatment devices are less mutagenic than older ones. The residual mutagenicity is linked to the gas phase and could be due to pro

  17. AGE Bio Diesel Emissions Evaluation

    DTIC Science & Technology

    2003-12-01

    98 30 96 Bw. Moisture, % by volume 51 43 47 47 i•(.a,) Moisture (at saturation), % by volume 102632 120475 12292.4 115344 V~ td Standard Water Vapor...inches Hg 30 68 30.69 30 69 30 69 B, Moisture, % by volume 3.4 5.3 50 4.6 Bwg (_t) Moisture (at saturation), % by volume 248 8 2487 248.7 248 7 Vtd...An Nozzle Area, ft’ 0000207 0000183 0000183 0000191 Vm(=rj Standard Meter Volume, ft" 47 172 42 863 44 329 44788 V.(. td ) Standard Meter Volume, m’ 1

  18. The potential origin of glioblastoma initiating cells

    PubMed Central

    Chesler, David A.; Berger, Mitchell S.; Quinones-Hinojosa, Alfredo

    2013-01-01

    Despite intensive clinical and laboratory research and effort, Glioblastoma remains the most common and invariably lethal primary cancer of the central nervous system. The identification of stem cell and lineage-restricted progenitor cell populations within the adult human brain in conjunction with the discovery of stem-like cells derived from gliomas which are themselves tumorigenic and have been shown to have properties of self-renewal and multipotency, has led to the hypothesis that this population of cells may represent glioma initiating cells. Extensive research characterizing the anatomic distribution and phenotype of neural stem cells in the adult brain, and the genetic underpinnings needed for malignant transformation may ultimately lead to the identification of the cellular origin for glioblastoma. Defining the cellular origin of this lethal disease may ultimately provide new therapeutic targets and modalities finally altering an otherwise bleak outcome for patients with glioblastoma. PMID:22202053

  19. Action potential initiation and propagation in rat neocortical pyramidal neurons.

    PubMed

    Stuart, G; Schiller, J; Sakmann, B

    1997-12-15

    1. Initiation and propagation of action potentials evoked by extracellular synaptic stimulation was studied using simultaneous dual and triple patch pipette recordings from different locations on neocortical layer 5 pyramidal neurons in brain slices from 4-week-old rats (P26-30) at physiological temperatures. 2. Simultaneous cell-attached and whole-cell voltage recordings from the apical trunk (up to 700 microns distal to the soma) and the soma indicated that proximal synaptic stimulation (layer 4) initiated action potentials first at the soma, whereas distal stimulation (upper layer 2/3) could initiate dendritic regenerative potentials prior to somatic action potentials following stimulation at higher intensity. 3. Somatic action potentials, once initiated, propagated back into the apical dendrites in a decremented manner which was frequency dependent. The half-width of back propagating action potentials increased and their maximum rate of rise decreased with distance from the soma, with the peak of these action potentials propagating with a conduction velocity of approximately 0.5 m s-1. 4. Back-propagation of action potentials into the dendritic tree was associated with dendritic calcium electrogenesis, which was particularly prominent during bursts of somatic action potentials. 5. When dendritic regenerative potentials were evoked prior to somatic action potentials, the more distal the dendritic recording was made from the soma the longer the time between the onset of the dendritic regenerative potential relative to somatic action potential. This suggested that dendritic regenerative potentials were initiated in the distal apical dendrites, possibly in the apical tuft. 6. At any one stimulus intensity, the initiation of dendritic regenerative potentials prior to somatic action potentials could fluctuate, and was modulated by depolarizing somatic or hyperpolarizing dendritic current injection. 7. Dendritic regenerative potentials could be initiated prior to

  20. Unique features of action potential initiation in cortical neurons.

    PubMed

    Naundorf, Björn; Wolf, Fred; Volgushev, Maxim

    2006-04-20

    Neurons process and encode information by generating sequences of action potentials. For all spiking neurons, the encoding of single-neuron computations into sequences of spikes is biophysically determined by the cell's action-potential-generating mechanism. It has recently been discovered that apparently minor modifications of this mechanism can qualitatively change the nature of neuronal encoding. Here we quantitatively analyse the dynamics of action potential initiation in cortical neurons in vivo, in vitro and in computational models. Unexpectedly, key features of the initiation dynamics of cortical neuron action potentials--their rapid initiation and variable onset potential--are outside the range of behaviours described by the classical Hodgkin-Huxley theory. We propose a new model based on the cooperative activation of sodium channels that reproduces the observed dynamics of action potential initiation. This new model predicts that Hodgkin-Huxley-type dynamics of action potential initiation can be induced by artificially decreasing the effective density of sodium channels. In vitro experiments confirm this prediction, supporting the hypothesis that cooperative sodium channel activation underlies the dynamics of action potential initiation in cortical neurons.

  1. Tumor Initiation in Human Malignant Melanoma and Potential Cancer Therapies

    PubMed Central

    Ma, Jie; Frank, Markus H.

    2010-01-01

    Cancer stem cells (CSCs), also known as tumor-initiating cells, have been identified in several human malignancies, including human malignant melanoma. The frequency of malignant melanoma-initiating cells (MMICs), which are identified by their expression of ATP-binding cassette (ABC) family member ABCB5, correlates with disease progression in human patients. Furthermore, targeted MMIC ablation through ABCB5 inhibits tumor initiation and growth in preclinical xenotransplantation models, pointing to potential therapeutic promise of the CSC concept. Recent advances also show that CSCs can exert pro-angiogenic roles in tumor growth and serve immunomodulatory functions related to the evasion of host anti-tumor immunity. Thus, MMICs might initiate and sustain tumorigenic growth not only as a result of CSC-intrinsic self-renewal, differentiation and proliferative capacity, but also based on pro-tumorigenic interactions with the host environment. PMID:20184545

  2. Tumor initiation in human malignant melanoma and potential cancer therapies.

    PubMed

    Ma, Jie; Frank, Markus H

    2010-02-01

    Cancer stem cells (CSCs), also known as tumor-initiating cells, have been identified in several human malignancies, including human malignant melanoma. The frequency of malignant melanoma-initiating cells (MMICs), which are identified by their expression of ATP-binding cassette (ABC) family member ABCB5, correlates with disease progression in human patients. Furthermore, targeted MMIC ablation through ABCB5 inhibits tumor initiation and growth in preclinical xenotransplantation models, pointing to potential therapeutic promise of the CSC concept. Recent advances also show that CSCs can exert pro-angiogenic roles in tumor growth and serve immunomodulatory functions related to the evasion of host anti-tumor immunity. Thus, MMICs might initiate and sustain tumorigenic growth not only as a result of CSC-intrinsic self-renewal, differentiation and proliferative capacity, but also based on pro-tumorigenic interactions with the host environment.

  3. Initial and serial evoked potentials in cerebrovascular critical care patients.

    PubMed

    Haupt, Walter F; Pawlik, Gunter; Thiel, Alexander

    2006-10-01

    Results of somatosensory evoked potential (SEP) and brainstem auditory evoked potential (BAEP) examinations performed early in the clinical course of patients with acute cerebrovascular disease correlate statistically significantly with outcome regardless of type and localization of the primary lesion. The prognostic value of serial examinations of SEP and BAEP has not been studied yet. The authors examined a group of 215 patients suffering from acute stroke requiring neurocritical care composed of 75 supratentorial and 36 infratentorial ischemic strokes, 58 supratentorial and 18 infratentorial hemorrhages, and 28 aneurysmatic subarachnoid hemorrhages prospectively using spinal and cortical SEP and BAEP according to routine procedures on admission as well as after 1 and 2 weeks. The findings were correlated to outcome at 4 weeks. Statistical assessment was performed using standard methods of contingency analysis. In all groups, SEP findings were significantly correlated with outcome at initial and all subsequent examinations, similar correlations were also found for BAEP. However, after partialling out the prognostic information gained from the initial examination of SEP and BAEP, the follow-up examinations rendered only a marginal increase in prognostic information. Therefore, the initial examination of evoked potentials supplies valuable prognostic information, however, serial examinations of evoked potentials during the first weeks of disease improve the prognostic information only marginally.

  4. Action Potential Initiation in the Hodgkin-Huxley Model

    PubMed Central

    Colwell, Lucy J.; Brenner, Michael P.

    2009-01-01

    A recent paper of B. Naundorf et al. described an intriguing negative correlation between variability of the onset potential at which an action potential occurs (the onset span) and the rapidity of action potential initiation (the onset rapidity). This correlation was demonstrated in numerical simulations of the Hodgkin-Huxley model. Due to this antagonism, it is argued that Hodgkin-Huxley-type models are unable to explain action potential initiation observed in cortical neurons in vivo or in vitro. Here we apply a method from theoretical physics to derive an analytical characterization of this problem. We analytically compute the probability distribution of onset potentials and analytically derive the inverse relationship between onset span and onset rapidity. We find that the relationship between onset span and onset rapidity depends on the level of synaptic background activity. Hence we are able to elucidate the regions of parameter space for which the Hodgkin-Huxley model is able to accurately describe the behavior of this system. PMID:19148265

  5. Action potential initiation in the hodgkin-huxley model.

    PubMed

    Colwell, Lucy J; Brenner, Michael P

    2009-01-01

    A recent paper of B. Naundorf et al. described an intriguing negative correlation between variability of the onset potential at which an action potential occurs (the onset span) and the rapidity of action potential initiation (the onset rapidity). This correlation was demonstrated in numerical simulations of the Hodgkin-Huxley model. Due to this antagonism, it is argued that Hodgkin-Huxley-type models are unable to explain action potential initiation observed in cortical neurons in vivo or in vitro. Here we apply a method from theoretical physics to derive an analytical characterization of this problem. We analytically compute the probability distribution of onset potentials and analytically derive the inverse relationship between onset span and onset rapidity. We find that the relationship between onset span and onset rapidity depends on the level of synaptic background activity. Hence we are able to elucidate the regions of parameter space for which the Hodgkin-Huxley model is able to accurately describe the behavior of this system.

  6. Potential distribution and discharge initiation potential in dielectric plane in the presence of earthed sphere

    NASA Astrophysics Data System (ADS)

    Vila, F.

    1994-08-01

    In this work we have studied theoretically the potential distribution and the initial discharge potential in an entirely symmetric system, grounded sphere-uniformly charged dielectric plane. The theoretical results of this model are applied successfully to the calandre processes of the paper industry.

  7. Readiness potential and movement initiation in the rat.

    PubMed

    Seki, Tomomi; Gemba, Hisae; Matsuzaki, Ryuichi; Nakao, Kazuko

    2005-02-01

    Cortical field potentials were recorded by electrodes implanted chronically on the surface and at a 2.0 mm depth in various cortical areas in the left hemisphere in the rat during self-paced movements of the right forelimb. A surface-negative (s-N), depth-positive (d-P) cortical field potential appeared about 1.0 s (range: 0.5-1.5 s) before movement onset in the rostral (RFA) and caudal (CFA) forelimb areas of the motor cortex, and the somatosensory cortex, but not in the occipital cortex. Bipolar recording of electromyographic activities induced by the electrical stimulation of various cortical loci was also performed by pairs of steel electrodes inserted in the face, trunk, forelimb and hindlimb muscles on both sides. The stimulation of the forelimb motor cortex activated the face and/or forelimb muscles, while that of the somatosensory cortex generally activated several body part muscles including the forelimb muscle. Stronger stimulus intensity was requested to elicit the activities of most of the ipsilateral muscles to the cortex stimulated than the contralateral ones. The minimum intensity for inducing the forelimb muscle activity was lowest in the CFA among cortical areas producing the activity. The stimulation of cortical loci in which the s-N, d-P potential was recorded could induce muscle activities in the forelimb contralateral to the stimulation. It is suggested that the s-N, d-P potential is the readiness potential for activating muscles to initiate movement in the rat forelimb.

  8. Action potential initiation and propagation in CA3 pyramidal axons.

    PubMed

    Meeks, Julian P; Mennerick, Steven

    2007-05-01

    Thin, unmyelinated axons densely populate the mammalian hippocampus and cortex. However, the location and dynamics of spike initiation in thin axons remain unclear. We investigated basic properties of spike initiation and propagation in CA3 neurons of juvenile rat hippocampus. Sodium channel alpha subunit distribution and local applications of tetrodotoxin demonstrate that the site of first threshold crossing in CA3 neurons is approximately 35 microm distal to the soma, somewhat more proximal than our previous estimates. This discrepancy can be explained by the finding, obtained with simultaneous whole cell somatic and extracellular axonal recordings, that a zone of axon stretching to approximately 100 microm distal to the soma reaches a maximum rate of depolarization nearly synchronously by the influx of sodium from the high-density channels. Models of the proximal axon incorporating observed distributions of sodium channel staining recapitulated salient features of somatic and axonal spike waveforms, including the predicted initiation zone, characteristic spike latencies, and conduction velocity. The preferred initiation zone was unaltered by stimulus strength or repetitive spiking, but repetitive spiking increased threshold and significantly slowed initial segment recruitment time and conduction velocity. Our work defines the dynamics of initiation and propagation in hippocampal principal cell axons and may help reconcile recent controversies over initiation site in other axons.

  9. Evaluating Subduction Initiation Potential on the Present-Day Earth

    NASA Astrophysics Data System (ADS)

    Johnston, M. D.; Long, M. D.; Silver, P. G.

    2008-12-01

    Subduction, the process by which oceanic lithosphere is recycled into the Earth's mantle, is a central component of plate tectonic theory. However, the process by which new subduction zones initiate is not well understood. Several different models have been proposed, such as passive margin collapse aided by a mechanism for lithospheric weakening, polarity reversal at an active subduction zone, and gravitational collapse at a fracture zone or other preexisting zone of lithospheric weakness. In this study, we focus on the third type of mechanism, which has been explored through numerical models by Hall et al. (2003) and Gurnis et al. (2004). These models describe three conditions necessary for subduction initiation: presence of a fracture zone, offset in the age of the ocean floor along the fracture zone, and significant compression normal to the fracture zone. We evaluate the predictions of the Gurnis et al. (2004) model on the present-day Earth. With digital seafloor age data and global stress models we calculate a parameter predicting the location of relatively likely subduction initiation on the ocean floor. We compile a database of oceanic fracture zones with associated age offsets from seafloor age maps and evaluate the state of stress on each fault segment using the global stress models of Lithgow-Bertelloni and Guynn (2004) and Ghosh (2008). For each fault segment we calculate a "subduction initiation likelihood parameter" as the normalized magnitude of the stress normal to the fault strike. In this way, we identify fault segments that may undergo compressive strain as they have significant compressive stress normal to the fault strike. For many fault segments, our parameter depends heavily on which stress model is employed. We predict regions of relatively likely subduction initiation, including regions in the northern Pacific and Indian oceans. The evaluation of predictions of models for subduction initiation on the present-day Earth should lead to a better

  10. Instructional and Information Technology Initiatives: The Potential for Delivery.

    ERIC Educational Resources Information Center

    Eisner, John

    1992-01-01

    Strategies that can be used by the dental education profession to develop instructional and information technologies to support curricular reform are proposed. Focus is on strategies that can be successful in a period of scarce institutional resources. Issues discussed include selecting initiatives, technology standards, intellectual property,…

  11. Potential biochemical events associated with initiation of labor.

    PubMed

    Vidaeff, A C; Ramin, S M

    2008-01-01

    Much of our understanding and knowledge of human parturition has been blurred by conjecture and extrapolation. The limited available data on human parturition reflect the inability to directly experiment with pregnant human subjects. In spite of this obvious impediment and the scarcity of longitudinal data on fundamental physiological changes in human pregnancy, recent reports have generated a better understanding of the synchronous activities leading to labor. The purpose of this review was to organize, in an evidence-based format, the current understanding of maternal physiologic phenomena leading from uterine quiescence to uterine labor activity. Recent discoveries have prompted a revision of pre-existing classical theories on the initiation of parturition, such as the progesterone block theory or the prostaglandins stimulation of the uterotonic action of oxytocin. The presence in the circulation of extrahypothalamic corticotrophin-releasing hormone (CRH) produced by the placenta and myometrium is an inciting unique feature of primate pregnancy and a promising field for research. The concept of anatomical regionalization in labor promotion, including the cervical physiological inflammatory reaction, is also discussed in the review, especially in support of the strong link between inflammatory activation and onset of preterm labor. Understanding the intimate chain of events leading to parturition is critical, and elucidating the interplay of signals and processes that initiate normal labor may help us to understand the abnormal variant, spontaneous preterm labor, and devise efficacious interventions against it.

  12. The National Nanotechnology Initiative: Potential Impact on DoD

    DTIC Science & Technology

    2007-03-19

    realizing that potential will not be easy. Emerging Technology Example: Non-volatile, high density memory Nanostructures hold promise for the...higher efficiency combustion, and greater thrust in rocket propulsion. Emerging Technology Example: Rapid rechargeable battery electrodes The...illustrated by carbon nanotube composites where there has been considerable work, but limited results17. Emerging Technology Example: Nanoclay

  13. Evaluating the potential effectiveness of proposed environmental justice initiatives

    SciTech Connect

    Greenfield, N.L.; Namovicz, C.R.

    1994-12-31

    Congress directed the US Environmental Protection Agency (EPA) to create the Technical Assistance Grant (TAG) program to address the concerns of these citizens and, thereby improve community relations at Superfund sites. TAGs provide funding to allow affected residents to hire independent scientific and technical consultants to help them understand the issues at the site and better participate in remedy selection. This study will not directly assess the experience of Environmental Justice sites within the Superfund program. Rather, this study examines existing data on TAGs and the applicability of an expanded TAG program in addressing expressed Environmental Justice concerns. Specifically, the study compares the characteristics of sites with TAGs to a matched control group of sites/communities without TAGs. The study establishes a rigorous statistical baseline upon which it can evaluate the marginal contribution of outreach initiatives to the needs and concerns of minority and low income communities. The results of these analyses will serve as a foundation for evaluating proposed changes in the scope and emphasis of Superfund`s community relations and Environmental Justice outreach programs.

  14. 7 CFR 1945.19 - Reporting potential natural disasters and initial actions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 13 2010-01-01 2009-01-01 true Reporting potential natural disasters and initial... Assistance-General § 1945.19 Reporting potential natural disasters and initial actions. (a) Purpose. The purpose of reporting potential natural disasters is to provide a systematic procedure for rapid...

  15. 7 CFR 1945.19 - Reporting potential natural disasters and initial actions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 13 2011-01-01 2009-01-01 true Reporting potential natural disasters and initial... Assistance-General § 1945.19 Reporting potential natural disasters and initial actions. (a) Purpose. The purpose of reporting potential natural disasters is to provide a systematic procedure for rapid...

  16. 7 CFR 1945.19 - Reporting potential natural disasters and initial actions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 13 2012-01-01 2012-01-01 false Reporting potential natural disasters and initial... Assistance-General § 1945.19 Reporting potential natural disasters and initial actions. (a) Purpose. The purpose of reporting potential natural disasters is to provide a systematic procedure for rapid...

  17. Ballistic missile defense: a potential arms-control initiative

    SciTech Connect

    Barasch, G.E.; Kerr, D.M.; Kupperman, R.H.; Pollock, R.; Smith, H.A.

    1981-01-01

    US strategic forces must be restructured to meet national-security objectives in a changing world. Growth and modernization of Soviet strategic missile forces are causing our land-based strategic missiles to become increasingly vulnerable to Soviet nuclear attack. For some strategic force configurations, the goals of flexible nuclear deterrence and strategic arms limitations appear mutually inconsistent. With such forces, prospects for arms limitations would degrade further if the current Soviet build-up were to continue, or if the Soviets were to install unilaterally an anti-ballistic missile system capable of wide-area, multicity defense, or both. However, if the US installs an anti-ballistic missile system along with reduced but modernized offensive strategic forces, arms limitation appears compatible with both assured destruction and war-fighting deterrence policies. This conclusion appears equally valid for expanded Soviet forces even if the Soviets also install ballistic missile defenses. In particular, an American strategic posture including layered defense of MX missiles based deceptively in silos was analyzed. The exoatmospheric-intercept component of this defense system could also defend some of our cities and industrial and military installations. If the US were to adopt this strategic posture, we believe it would create incentives for the Soviet Union to restrain strategic-armsexpansion. Mutual arms-control initiatives could follow. Test and installation of the needed defensive systems are now precluded by the Anti-Ballistic-Missile Treaty adopted in 1972. An opportunity for Treaty reconsideration occurs in 1982. Substantiation of our results would suggest that consideration be given to Treaty modifications or to replacing the Treaty with other agreements.

  18. Axonal action-potential initiation and Na+ channel densities in the soma and axon initial segment of subicular pyramidal neurons.

    PubMed

    Colbert, C M; Johnston, D

    1996-11-01

    A long-standing hypothesis is that action potentials initiate first in the axon hillock/initial segment (AH-IS) region because of a locally high density of Na+ channels. We tested this idea in subicular pyramidal neurons by using patch-clamp recordings in hippocampal slices. Simultaneous recordings from the soma and IS confirmed that orthodromic action potentials initiated in the axon and then invaded the soma. However, blocking Na+ channels in the AH-IS with locally applied tetrodotoxin (TTX) did not raise the somatic threshold membrane potential for orthodromic spikes. TTX applied to the axon beyond the AH-IS (30-60 microm from the soma) raised the apparent somatic threshold by approximately 8 mV. We estimated the Na+ current density in the AH-IS and somatic membranes by using cell-attached patch-clamp recordings and found similar magnitudes (3-4 pA/microm2). Thus, the present results suggest that orthodromic action potentials initiate in the axon beyond the AH-IS and that the minimum threshold for spike initiation of the neuron is not determined by a high density of Na+ channels in the AH-IS region.

  19. Action potentials initiate in the axon initial segment and propagate through axon collaterals reliably in cerebellar Purkinje neurons.

    PubMed

    Foust, Amanda; Popovic, Marko; Zecevic, Dejan; McCormick, David A

    2010-05-19

    Purkinje neurons are the output cells of the cerebellar cortex and generate spikes in two distinct modes, known as simple and complex spikes. Revealing the point of origin of these action potentials, and how they conduct into local axon collaterals, is important for understanding local and distal neuronal processing and communication. By using a recent improvement in voltage-sensitive dye imaging technique that provided exceptional spatial and temporal resolution, we were able to resolve the region of spike initiation as well as follow spike propagation into axon collaterals for each action potential initiated on single trials. All fast action potentials, for both simple and complex spikes, whether occurring spontaneously or in response to a somatic current pulse or synaptic input, initiated in the axon initial segment. At discharge frequencies of less than approximately 250 Hz, spikes propagated faithfully through the axon and axon collaterals, in a saltatory manner. Propagation failures were only observed for very high frequencies or for the spikelets associated with complex spikes. These results demonstrate that the axon initial segment is a critical decision point in Purkinje cell processing and that the properties of axon branch points are adjusted to maintain faithful transmission.

  20. [Effect of the initial anode potential on electricity generation in microbial fuel cell].

    PubMed

    Fan, Ming-Zhi; Liang, Peng; Cao, Xiao-Xin; Huang, Xia

    2008-01-01

    The initial anode potential of the microbial fuel cell (MFC) was changed by additional circuit in the anode chamber, and the influence of the initial anode potential on the electricigens was studied. When the initial anode potential was 350 mV (vs Hg/Hg2 Cl2), the growth of microorganisms was much slower than that of the microorganisms which grew on the anode with an initial potential of -200 mV or 200 mV (vs Hg/Hg2 Cl2). After stable electricity generation, the anode resistances of the three MFCs, which had initial anode potentials of 350 mV, 200 mV and -200 mV respectively, were 71 Omega, 43 Omega and 80 Omega. The community structures in MFCs, before and after the electricity generation, were also studied by denaturing gradient gel electrophoresis (DGGE). Clostridium sticklandii, Pseudomonas mendocina and Paenibacillus taejonensis were the three most enriched strains on the anode.

  1. Physical properties of bio-diesel & Implications for use of bio-diesel in diesel engines

    SciTech Connect

    Chakravarthy, Veerathu K; McFarlane, Joanna; Daw, C Stuart; Ra, Youngchul; Griffin, Jelani K

    2008-01-01

    In this study we identify components of a typical biodiesel fuel and estimate both their individual and mixed thermo-physical and transport properties. We then use the estimated mixture properties in computational simulations to gauge the extent to which combustion is modified when biodiesel is substituted for conventional diesel fuel. Our simulation studies included both regular diesel combustion (DI) and premixed charge compression ignition (PCCI). Preliminary results indicate that biodiesel ignition is significantly delayed due to slower liquid evaporation, with the effects being more pronounced for DI than PCCI. The lower vapor pressure and higher liquid heat capacity of biodiesel are two key contributors to this slower rate of evaporation. Other physical properties are more similar between the two fuels, and their impacts are not clearly evident in the present study. Future studies of diesel combustion sensitivity to both physical and chemical properties of biodiesel are suggested.

  2. Action potentials in retinal ganglion cells are initiated at the site of maximal curvature of the extracellular potential.

    PubMed

    Eickenscheidt, Max; Zeck, Günther

    2014-06-01

    The initiation of an action potential by extracellular stimulation occurs after local depolarization of the neuronal membrane above threshold. Although the technique shows remarkable clinical success, the site of action and the relevant stimulation parameters are not completely understood. Here we identify the site of action potential initiation in rabbit retinal ganglion cells (RGCs) interfaced to an array of extracellular capacitive stimulation electrodes. We determine which feature of the extracellular potential governs action potential initiation by simultaneous stimulation and recording RGCs interfaced in epiretinal configuration. Stimulation electrodes were combined to areas of different size and were presented at different positions with respect to the RGC. Based on stimulation by electrodes beneath the RGC soma and simultaneous sub-millisecond latency measurement we infer axonal initiation at the site of maximal curvature of the extracellular potential. Stimulation by electrodes at different positions along the axon reveals a nearly constant threshold current density except for a narrow region close to the cell soma. These findings are explained by the concept of the activating function modified to consider a region of lower excitability close to the cell soma. We present a framework how to estimate the site of action potential initiation and the stimulus required to cross threshold in neurons tightly interfaced to capacitive stimulation electrodes. Our results underscore the necessity of rigorous electrical characterization of the stimulation electrodes and of the interfaced neural tissue.

  3. Action potentials in retinal ganglion cells are initiated at the site of maximal curvature of the extracellular potential

    NASA Astrophysics Data System (ADS)

    Eickenscheidt, Max; Zeck, Günther

    2014-06-01

    Objective. The initiation of an action potential by extracellular stimulation occurs after local depolarization of the neuronal membrane above threshold. Although the technique shows remarkable clinical success, the site of action and the relevant stimulation parameters are not completely understood. Approach. Here we identify the site of action potential initiation in rabbit retinal ganglion cells (RGCs) interfaced to an array of extracellular capacitive stimulation electrodes. We determine which feature of the extracellular potential governs action potential initiation by simultaneous stimulation and recording RGCs interfaced in epiretinal configuration. Stimulation electrodes were combined to areas of different size and were presented at different positions with respect to the RGC. Main results. Based on stimulation by electrodes beneath the RGC soma and simultaneous sub-millisecond latency measurement we infer axonal initiation at the site of maximal curvature of the extracellular potential. Stimulation by electrodes at different positions along the axon reveals a nearly constant threshold current density except for a narrow region close to the cell soma. These findings are explained by the concept of the activating function modified to consider a region of lower excitability close to the cell soma. Significance. We present a framework how to estimate the site of action potential initiation and the stimulus required to cross threshold in neurons tightly interfaced to capacitive stimulation electrodes. Our results underscore the necessity of rigorous electrical characterization of the stimulation electrodes and of the interfaced neural tissue.

  4. Spikelets in Pyramidal Neurons: Action Potentials Initiated in the Axon Initial Segment That Do Not Activate the Soma

    PubMed Central

    Michalikova, Martina; Kempter, Richard

    2017-01-01

    Spikelets are small spike-like depolarizations that can be measured in somatic intracellular recordings. Their origin in pyramidal neurons remains controversial. To explain spikelet generation, we propose a novel single-cell mechanism: somato-dendritic input generates action potentials at the axon initial segment that may fail to activate the soma and manifest as somatic spikelets. Using mathematical analysis and numerical simulations of compartmental neuron models, we identified four key factors controlling spikelet generation: (1) difference in firing threshold, (2) impedance mismatch, and (3) electrotonic separation between the soma and the axon initial segment, as well as (4) input amplitude. Because spikelets involve forward propagation of action potentials along the axon while they avoid full depolarization of the somato-dendritic compartments, we conjecture that this mode of operation saves energy and regulates dendritic plasticity while still allowing for a read-out of results of neuronal computations. PMID:28068338

  5. A Critical Role for Neurofascin in Regulating Action Potential Initiation through Maintenance of the Axon Initial Segment

    PubMed Central

    Zonta, Barbara; Desmazieres, Anne; Rinaldi, Arianna; Tait, Steven; Sherman, Diane L.; Nolan, Matthew F.; Brophy, Peter J.

    2011-01-01

    Summary The axon initial segment (AIS) is critical for the initiation and propagation of action potentials. Assembly of the AIS requires interactions between scaffolding molecules and voltage-gated sodium channels, but the molecular mechanisms that stabilize the AIS are poorly understood. The neuronal isoform of Neurofascin, Nfasc186, clusters voltage-gated sodium channels at nodes of Ranvier in myelinated nerves: here, we investigate its role in AIS assembly and stabilization. Inactivation of the Nfasc gene in cerebellar Purkinje cells of adult mice causes rapid loss of Nfasc186 from the AIS but not from nodes of Ranvier. This causes AIS disintegration, impairment of motor learning and the abolition of the spontaneous tonic discharge typical of Purkinje cells. Nevertheless, action potentials with a modified waveform can still be evoked and basic motor abilities remain intact. We propose that Nfasc186 optimizes communication between mature neurons by anchoring the key elements of the adult AIS complex. PMID:21382554

  6. 45 CFR 150.303 - Basis for initiating an investigation of a potential violation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... potential violation. 150.303 Section 150.303 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES... for initiating an investigation of a potential violation. (a) Information. Any information that... State agencies. (3) Any other information that indicates potential noncompliance with HIPAA requirements...

  7. 45 CFR 150.303 - Basis for initiating an investigation of a potential violation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... potential violation. 150.303 Section 150.303 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES REQUIREMENTS RELATING TO HEALTH CARE ACCESS CMS ENFORCEMENT IN GROUP AND INDIVIDUAL INSURANCE MARKETS CMS... for initiating an investigation of a potential violation. (a) Information. Any information that...

  8. Fatigue crack initiation potential from defects in terms of local stress analysis

    NASA Astrophysics Data System (ADS)

    Zhu, Mingliang; Xuan, Fuzhen

    2014-05-01

    The competition of surface and subsurface crack initiation induced failure is critical to understand very high cycle fatigue(VHCF) behavior, which necessitates the elucidation of the underlying mechanisms for the transition of crack initiation from surface to interior defects. Crack initiation potential in materials containing defects is investigated numerically by focusing on defect types, size, shape, location, and residual stress influences. Results show that the crack initiation potency is higher in case of serious property mismatching between matrix and defects, and higher strength materials are more sensitive to soft inclusions(elastic modulus lower than the matrix). The stress localization around inclusions are correlated to interior crack initiation mechanisms in the VHCF regime such as inclusion-matrix debonding at soft inclusions and inclusion-cracking for hard inclusions(elastic modulus higher than the matrix). It is easier to emanate cracks from the subsurface pores with the depth 0.7 times as large as their diameter. There exists an inclusion size independent region for crack incubation, outside which crack initiation will transfer from the subsurface soft inclusion to the interior larger one. As for elliptical inclusions, reducing the short-axis length can decrease the crack nucleation potential and promote the interior crack formation, whereas the long-axis length controls the site of peak stress concentration. The compressive residual stress at surface is helpful to shift crack initiation from surface to interior inclusions. Some relaxation of residual stress can not change the inherent crack initiation from interior inclusions in the VHCF regime. The work reveals the crack initiation potential and the transition among various defects under the influences of both intrinsic and extrinsic factors in the VHCF regime, and is helpful to understand the failure mechanism of materials containing defects under long-term cyclic loadings.

  9. Neuronal adaptation involves rapid expansion of the action potential initiation site

    PubMed Central

    Scott, Ricardo S.; Henneberger, Christian; Padmashri, Ragunathan; Anders, Stefanie; Jensen, Thomas P.; Rusakov, Dmitri A.

    2014-01-01

    Action potential (AP) generation is the key to information-processing in the brain. Although APs are normally initiated in the axonal initial segment, developmental adaptation or prolonged network activity may alter the initiation site geometry thus affecting cell excitability. Here we find that hippocampal dentate granule cells adapt their spiking threshold to the kinetics of the ongoing dendrosomatic excitatory input by expanding the AP-initiation area away from the soma while also decelerating local axonal spikes. Dual-patch soma–axon recordings combined with axonal Na+ and Ca2+ imaging and biophysical modelling show that the underlying mechanism involves distance-dependent inactivation of axonal Na+ channels due to somatic depolarization propagating into the axon. Thus, the ensuing changes in the AP-initiation zone and local AP propagation could provide activity-dependent control of cell excitability and spiking on a relatively rapid timescale. PMID:24851940

  10. Dynamics of Action Potential Initiation in the GABAergic Thalamic Reticular Nucleus In Vivo

    PubMed Central

    Muñoz, Fabián; Fuentealba, Pablo

    2012-01-01

    Understanding the neural mechanisms of action potential generation is critical to establish the way neural circuits generate and coordinate activity. Accordingly, we investigated the dynamics of action potential initiation in the GABAergic thalamic reticular nucleus (TRN) using in vivo intracellular recordings in cats in order to preserve anatomically-intact axo-dendritic distributions and naturally-occurring spatiotemporal patterns of synaptic activity in this structure that regulates the thalamic relay to neocortex. We found a wide operational range of voltage thresholds for action potentials, mostly due to intrinsic voltage-gated conductances and not synaptic activity driven by network oscillations. Varying levels of synchronous synaptic inputs produced fast rates of membrane potential depolarization preceding the action potential onset that were associated with lower thresholds and increased excitability, consistent with TRN neurons performing as coincidence detectors. On the other hand the presence of action potentials preceding any given spike was associated with more depolarized thresholds. The phase-plane trajectory of the action potential showed somato-dendritic propagation, but no obvious axon initial segment component, prominent in other neuronal classes and allegedly responsible for the high onset speed. Overall, our results suggest that TRN neurons could flexibly integrate synaptic inputs to discharge action potentials over wide voltage ranges, and perform as coincidence detectors and temporal integrators, supported by a dynamic action potential threshold. PMID:22279567

  11. Dynamics of action potential initiation in the GABAergic thalamic reticular nucleus in vivo.

    PubMed

    Muñoz, Fabián; Fuentealba, Pablo

    2012-01-01

    Understanding the neural mechanisms of action potential generation is critical to establish the way neural circuits generate and coordinate activity. Accordingly, we investigated the dynamics of action potential initiation in the GABAergic thalamic reticular nucleus (TRN) using in vivo intracellular recordings in cats in order to preserve anatomically-intact axo-dendritic distributions and naturally-occurring spatiotemporal patterns of synaptic activity in this structure that regulates the thalamic relay to neocortex. We found a wide operational range of voltage thresholds for action potentials, mostly due to intrinsic voltage-gated conductances and not synaptic activity driven by network oscillations. Varying levels of synchronous synaptic inputs produced fast rates of membrane potential depolarization preceding the action potential onset that were associated with lower thresholds and increased excitability, consistent with TRN neurons performing as coincidence detectors. On the other hand the presence of action potentials preceding any given spike was associated with more depolarized thresholds. The phase-plane trajectory of the action potential showed somato-dendritic propagation, but no obvious axon initial segment component, prominent in other neuronal classes and allegedly responsible for the high onset speed. Overall, our results suggest that TRN neurons could flexibly integrate synaptic inputs to discharge action potentials over wide voltage ranges, and perform as coincidence detectors and temporal integrators, supported by a dynamic action potential threshold.

  12. Serotonin spillover onto the axon initial segment of motoneurons induces central fatigue by inhibiting action potential initiation.

    PubMed

    Cotel, Florence; Exley, Richard; Cragg, Stephanie J; Perrier, Jean-François

    2013-03-19

    Motor fatigue induced by physical activity is an everyday experience characterized by a decreased capacity to generate motor force. Factors in both muscles and the central nervous system are involved. The central component of fatigue modulates the ability of motoneurons to activate muscle adequately independently of the muscle physiology. Indirect evidence indicates that central fatigue is caused by serotonin (5-HT), but the cellular mechanisms are unknown. In a slice preparation from the spinal cord of the adult turtle, we found that prolonged stimulation of the raphe-spinal pathway--as during motor exercise--activated 5-HT1A receptors that decreased motoneuronal excitability. Electrophysiological tests combined with pharmacology showed that focal activation of 5-HT1A receptors at the axon initial segment (AIS), but not on other motoneuronal compartments, inhibited the action potential initiation by modulating a Na(+) current. Immunohistochemical staining against 5-HT revealed a high-density innervation of 5-HT terminals on the somatodendritic membrane and a complete absence on the AIS. This observation raised the hypothesis that a 5-HT spillover activates receptors at this latter compartment. We tested it by measuring the level of extracellular 5-HT with cyclic voltammetry and found that prolonged stimulations of the raphe-spinal pathway increased the level of 5-HT to a concentration sufficient to activate 5-HT1A receptors. Together our results demonstrate that prolonged release of 5-HT during motor activity spills over from its release sites to the AIS of motoneurons. Here, activated 5-HT1A receptors inhibit firing and, thereby, muscle contraction. Hence, this is a cellular mechanism for central fatigue.

  13. Serotonin spillover onto the axon initial segment of motoneurons induces central fatigue by inhibiting action potential initiation

    PubMed Central

    Cotel, Florence; Exley, Richard; Cragg, Stephanie J.; Perrier, Jean-François

    2013-01-01

    Motor fatigue induced by physical activity is an everyday experience characterized by a decreased capacity to generate motor force. Factors in both muscles and the central nervous system are involved. The central component of fatigue modulates the ability of motoneurons to activate muscle adequately independently of the muscle physiology. Indirect evidence indicates that central fatigue is caused by serotonin (5-HT), but the cellular mechanisms are unknown. In a slice preparation from the spinal cord of the adult turtle, we found that prolonged stimulation of the raphe-spinal pathway—as during motor exercise—activated 5-HT1A receptors that decreased motoneuronal excitability. Electrophysiological tests combined with pharmacology showed that focal activation of 5-HT1A receptors at the axon initial segment (AIS), but not on other motoneuronal compartments, inhibited the action potential initiation by modulating a Na+ current. Immunohistochemical staining against 5-HT revealed a high-density innervation of 5-HT terminals on the somatodendritic membrane and a complete absence on the AIS. This observation raised the hypothesis that a 5-HT spillover activates receptors at this latter compartment. We tested it by measuring the level of extracellular 5-HT with cyclic voltammetry and found that prolonged stimulations of the raphe-spinal pathway increased the level of 5-HT to a concentration sufficient to activate 5-HT1A receptors. Together our results demonstrate that prolonged release of 5-HT during motor activity spills over from its release sites to the AIS of motoneurons. Here, activated 5-HT1A receptors inhibit firing and, thereby, muscle contraction. Hence, this is a cellular mechanism for central fatigue. PMID:23487756

  14. Detonation initiation in solid explosive: MD simulation using AB interatomic potential

    NASA Astrophysics Data System (ADS)

    Murzov, Semen; Zhakhovsky, Vasily

    2017-01-01

    The classical molecular dynamics method is used for atomistic simulation of detonation initiation in AB model of condensed phase explosive, in which the simplified REBO potential defines reactive interatomic interactions between atoms period A and B. The simulated ultra-short (picoseconds) shock wave (SW) compression of an explosive corresponds to indirect detonation initiation produced by femtosecond laser pulses. We study shock to detonation transition (SDT) including the evolution of pressure profiles in an AB explosive film. It is demonstrated that the pressure profile of detonation wave (DW) can be calculated from a time-dependent rear-surface velocity measured in experiments. The role of a single cylindrical pore in detonation initiation is investigated. The thresholds for long-term (tens of picosecond) and sustained loading initiating regimes are determined.

  15. Neuronal Competition for Action Potential Initiation Sites in a Circuit Controlling Simple Learning

    PubMed Central

    Cruz, Georgina E.; Sahley, Christie L.; Muller, Kenneth J.

    2007-01-01

    The spatial and temporal patterns of action potential initiations were studied in a behaving leech preparation to determine the basis of increased firing that accompanies sensitization, a form of non-associative learning requiring the S-interneurons. Little is known at the network level about mechanisms of behavioral sensitization. The S-interneurons, one in each ganglion and linked by electrical synapses with both neighbors to form a chain, are interposed between sensory and motor neurons. In sensitized preparations the strength of shortening is related to S-cell firing, which itself is the result of impulses initiating in several S-cells. Because the S-cells, as independent initiation sites, all contribute to activity in the chain, it was hypothesized that during sensitization, increased multi-site activity increased the chain's firing rate. However, it was found that during sensitization, the single site with the largest initiation rate, the S-cell in the stimulated segment, suppressed initiations in adjacent ganglia. Experiments showed this was both because (1) it received the earliest, greatest input and (2) the delayed synaptic input to the adjacent S-cells coincided with the action potential refractory period. A compartmental model of the S-cell and its inputs showed that a simple, intrinsic mechanism of inexcitability after each action potential may account for suppression of impulse initiations. Thus, a non-synaptic competition between neurons alters synaptic integration in the chain. In one mode, inputs to different sites sum independently, whereas in another, synaptic input to a single site precisely specifies the overall pattern of activity. PMID:17644266

  16. Physical activity initiatives for male factory workers: gatekeepers' perceptions of potential motivators and barriers.

    PubMed

    Veitch, J; Clavisi, O; Owen, N

    1999-10-01

    Worksites have been argued to be a key setting for physical activity promotion, particularly for lower-paid, less-skilled workers. These occupational groups are at increased risk of cardiovascular disease. There is no strong evidence in support of the efficacy of worksite fitness and physical activity interventions. This study assessed potential motivators and barriers to worksite physical activity initiatives for less-skilled workers. We conducted telephone interviews with 13 Victorian WorkCover insurance providers and 30 manufacturing industry worksite managers. The manufacturing industry was selected as it contains a substantial portion of workers from this high-risk occupational group. Most insurers incorporated physical activity elements into injury-prevention programs. Few worksite managers reported programs to encourage workers to be more active; they identified reduced premiums and lower-cost programs through insurers as possible motivators. Both groups identified workers' reluctance to participate in physical activity, lack of awareness of potential benefits and program cost as major barriers for worksite physical activity. Other barriers included potential adverse effects on productivity and increased injury risk. Broader occupational health and safety policies and joint initiatives between insurers and worksite managers may have the potential to provide more opportunities for workers to be more active. However, the barriers identified outweighed the perceived benefits. Without structural and regulatory changes or new incentives, the adoption of physical activity initiatives in Australian manufacturing-industry workplaces is unlikely.

  17. Cortical field potentials associated with audio-initiated vocalization in monkeys.

    PubMed

    Gemba, H; Kyuhou, S; Matsuzaki, R; Amino, Y

    1999-09-03

    Five monkeys vocalizing at self-pace (self-paced vocalization) were well trained to vocalize in response to a monkey call (audio-initiated vocalization). Field potentials associated with audio-initiated vocalizations were recorded by using electrodes which were implanted chronically on the surface and at a 2.0-3.0 mm depth in various cortical areas. A surface-negative (s-N), depth-positive (d-P) potential (at about 70 ms latency after stimulus onset) was recorded in the rostral bank of the inferior limb of the arcuate sulcus in the left hemisphere, in which an insignificant potential was associated with self-paced vocalizations. An s-N, d-P slow potential which occurred in the motor and somatosensory cortices with a latency of about 300 ms after stimulus, started about 700 ms before vocalizations. The duration and amplitude of this potential was substantially the same with those of the potential which occurred with self-paced vocalizations. Reaction times from stimulus onset to vocalization start were variable, but were about 0.9s on the average. The findings were discussed in connection with reaction-time hand movements.

  18. Axon initial segment Kv1 channels control axonal action potential waveform and synaptic efficacy.

    PubMed

    Kole, Maarten H P; Letzkus, Johannes J; Stuart, Greg J

    2007-08-16

    Action potentials are binary signals that transmit information via their rate and temporal pattern. In this context, the axon is thought of as a transmission line, devoid of a role in neuronal computation. Here, we show a highly localized role of axonal Kv1 potassium channels in shaping the action potential waveform in the axon initial segment (AIS) of layer 5 pyramidal neurons independent of the soma. Cell-attached recordings revealed a 10-fold increase in Kv1 channel density over the first 50 microm of the AIS. Inactivation of AIS and proximal axonal Kv1 channels, as occurs during slow subthreshold somatodendritic depolarizations, led to a distance-dependent broadening of axonal action potentials, as well as an increase in synaptic strength at proximal axonal terminals. Thus, Kv1 channels are strategically positioned to integrate slow subthreshold signals, providing control of the presynaptic action potential waveform and synaptic coupling in local cortical circuits.

  19. Native protein-initiated ATRP: a viable and potentially superior alternative to PEGylation for stabilizing biologics.

    PubMed

    Depp, Virginia; Alikhani, Azadeh; Grammer, Victoria; Lele, Bhalchandra S

    2009-02-01

    Comparison of in vitro serum stability and enzyme activity retention for PEGylated chymotrypsin and structurally different, biocompatible vinyl polymer grafts of chymotrypsin was performed. These polymer grafts were synthesized by atom transfer radical polymerization (ATRP) initiated by chymotrypsin covalently modified with 2-bromoisobutyric acid, the ATRP initiator. The maximum number of ATRP initiators attached to chymotrypsin was adjusted to be as close as possible to the maximum number of polyethylene glycol chains attached to chymotrypsin for better comparison and then polymerizations were conducted. In mouse serum, native and PEGylated chymotrypsin deactivated within 24h, whereas chymotrypsin-graft-poly(N-2-hydroxypropylmethacrylamide) retained >50% of its catalytic activity even after 5 days of incubation. In human serum, PEGylated chymotrypsin deactivated within 4 days of incubation, whereas native chymotrypsin and chymotrypsin-graft-poly(N-2-hydroxypropylmethacrylamide) and chymotrypsin-graft-poly(2-methacryloyloxyethyl phosphorylcholine) retained >25% catalytic activity after 5 days of incubation. Biocompatible vinyl polymer grafts of chymotrypsin synthesized by protein-initiated ATRP had higher catalytic activity retention and molecular weights and lower polydispersity than PEGylated chymotrypsin. In summary, studying the effects of structures of conjugated polymers on the stability and activity retention of modified proteins can lead to identification of a polymer-protein conjugate having superior pharmacological properties than conventionally PEGylated protein. Also, since vinyl monomers that form biocompatible polymers are easily polymerizable by ATRP, protein-initiated ATRP can become a viable and potentially superior alternative to PEGylation for stabilizing biologics.

  20. Active action potential propagation but not initiation in thalamic interneuron dendrites

    PubMed Central

    Casale, Amanda E.; McCormick, David A.

    2012-01-01

    Inhibitory interneurons of the dorsal lateral geniculate nucleus of the thalamus modulate the activity of thalamocortical cells in response to excitatory input through the release of inhibitory neurotransmitter from both axons and dendrites. The exact mechanisms by which release can occur from dendrites are, however, not well understood. Recent experiments using calcium imaging have suggested that Na/K based action potentials can evoke calcium transients in dendrites via local active conductances, making the back-propagating action potential a candidate for dendritic neurotransmitter release. In this study, we employed high temporal and spatial resolution voltage-sensitive dye imaging to assess the characteristics of dendritic voltage deflections in response to Na/K action potentials in interneurons of the mouse dorsal lateral geniculate nucleus. We found that trains or single action potentials elicited by somatic current injection or local synaptic stimulation led to action potentials that rapidly and actively back-propagated throughout the entire dendritic arbor and into the fine filiform dendritic appendages known to release GABAergic vesicles. Action potentials always appeared first in the soma or proximal dendrite in response to somatic current injection or local synaptic stimulation, and the rapid back-propagation into the dendritic arbor depended upon voltage-gated sodium and TEA-sensitive potassium channels. Our results indicate that thalamic interneuron dendrites integrate synaptic inputs that initiate action potentials, most likely in the axon initial segment, that then back-propagate with high-fidelity into the dendrites, resulting in a nearly synchronous release of GABA from both axonal and dendritic compartments. PMID:22171033

  1. Displaced Water Volume, Potential Energy of Initial Elevation, and Tsunami Intensity: Analysis of Recent Tsunami Events

    NASA Astrophysics Data System (ADS)

    Nosov, Mikhail A.; Bolshakova, Anna V.; Kolesov, Sergey V.

    2014-12-01

    We consider recent ocean-bottom earthquakes for which detailed slip distribution data are available. Using these data and the Okada formulae, we calculate the vector fields of co-seismic bottom deformations, which allow us to determine the displaced water volume and the potential energy of initial elevation of the tsunami source. It is shown that, in the majority of cases, the horizontal components of bottom deformation provide an additional contribution to the displaced water volume and virtually never diminish the contribution of the vertical component. The absolute value of the relative contribution of the horizontal components of bottom deformation to the displaced volume varies from 0.07 to 55 %, on average amounting to 14 %. The displaced volume and the energy of initial elevation (tsunami energy) are examined as functions of the moment magnitude, and the relevant regressions (least-squares fits) are derived. The obtained relationships exhibit good correspondence with the theoretical upper limits that had been obtained under the assumption of uniform slip distribution along a rectangular fault. Tsunami energy calculated on the basis of finite fault model data is compared with the earthquake energy determined from the energy-magnitude relationship by Kanamori. It is shown that tsunami takes from 0.001 to 0.34 % of the earthquake energy, and on average 0.04 %. Finally, we analyze the Soloviev-Imamura tsunami intensity as a function of the following three quantities: (1) the moment magnitude, (2) the decimal logarithm of the absolute value of displaced volume, and (3) the decimal logarithm of the potential energy of initial elevation. The first dependence exhibits rather poor correlation, whereas the second and third dependences demonstrate noticeably higher correlation coefficients. This gives us grounds to suggest considering the displaced volume and the energy of initial elevation as measures of the tsunamigenic potential of an earthquake.

  2. Initiation and blocking of the action potential in an axon in weak ultrasonic or microwave fields.

    PubMed

    Shneider, M N; Pekker, M

    2014-05-01

    In this paper, we analyze the effect of the redistribution of the transmembrane ion channels in an axon caused by longitudinal acoustic vibrations of the membrane. These oscillations can be excited by an external source of ultrasound and weak microwave radiation interacting with the charges sitting on the surface of the lipid membrane. It is shown, using the Hodgkin-Huxley model of the axon, that the density redistribution of transmembrane sodium channels may reduce the threshold of the action potential, up to its spontaneous initiation. At the significant redistribution of sodium channels in the membrane, the rarefaction zones of the transmembrane channel density are formed, blocking the propagation of the action potential. Blocking the action potential propagation along the axon is shown to cause anesthesia in the example case of a squid axon. Various approaches to experimental observation of the effects considered in this paper are discussed.

  3. Initiation and blocking of the action potential in an axon in weak ultrasonic or microwave fields

    NASA Astrophysics Data System (ADS)

    Shneider, M. N.; Pekker, M.

    2014-05-01

    In this paper, we analyze the effect of the redistribution of the transmembrane ion channels in an axon caused by longitudinal acoustic vibrations of the membrane. These oscillations can be excited by an external source of ultrasound and weak microwave radiation interacting with the charges sitting on the surface of the lipid membrane. It is shown, using the Hodgkin-Huxley model of the axon, that the density redistribution of transmembrane sodium channels may reduce the threshold of the action potential, up to its spontaneous initiation. At the significant redistribution of sodium channels in the membrane, the rarefaction zones of the transmembrane channel density are formed, blocking the propagation of the action potential. Blocking the action potential propagation along the axon is shown to cause anesthesia in the example case of a squid axon. Various approaches to experimental observation of the effects considered in this paper are discussed.

  4. A Perinatal Care Quality and Safety Initiative: Hospital Costs and Potential Savings

    PubMed Central

    Kozhimannil, Katy B.; Sommerness, Samantha; Rauk, Phillip; Gams, Rebecca; Hirt, Charles; Davis, Stanley; Miller, Kristi K.; Landers, Daniel V.

    2013-01-01

    Background There is increasing national focus on hospital initiatives to improve obstetric and neonatal outcomes. While costs of providing care may decrease with improved quality, the accompanying reduced adverse outcomes may impact hospital revenues. The purpose of this study was to estimate, from a hospital perspective, the financial impacts of implementing a perinatal quality and safety initiative. Methods In 2008, a Minnesota-based health system (Fairview Health Services) launched the Zero Birth Injury (ZBI) initiative, which uses evidence-based care bundles to guide management of obstetric services. We conducted a pre-post analysis of financial impacts of ZBI, using hospital administrative records to measure costs and revenues associated with changes in maternal and neonatal birth injuries before (2008) and after (2009–11) the initiative. Results After adjusting for relevant covariates, implementation of ZBI was associated with an 11% decrease in the rate of maternal and neonatal adverse outcomes between 2008 and 2011 (AOR=0.89, p=0.076). As a result of the adverse events avoided, the hospital system saved $284,985 in costs but earned $324,333 less revenue, which produced a net financial decrease of $39,348 (or a $305 net financial loss per adverse event avoided) in 2011, compared with 2008. Conclusions Adoption of a perinatal quality and safety initiative that reduced birth injuries had little net financial impact on the hospital. ZBI produced better clinical results at a lower cost, which represents potential savings for payers, but the hospital system offering increased quality reaped no clear financial rewards. These results highlight the important role for shared-savings collaborations (among patients, providers, government and third-party payers, and employers) to incentivize quality improvement. Widespread adoption of perinatal safety initiatives combined with innovative payment models may contribute to better health at reduced cost. PMID:23991507

  5. Non-lethal heat treatment of cells results in reduction of tumor initiation and metastatic potential

    SciTech Connect

    Kim, Yoo-Shin; Lee, Tae Hoon; O'Neill, Brian E.

    2015-08-14

    Non-lethal hyperthermia is used clinically as adjuvant treatment to radiation, with mixed results. Denaturation of protein during hyperthermia treatment is expected to synergize with radiation damage to cause cell cycle arrest and apoptosis. Alternatively, hyperthermia is known to cause tissue level changes in blood flow, increasing the oxygenation and radiosensitivity of often hypoxic tumors. In this study, we elucidate a third possibility, that hyperthermia alters cellular adhesion and mechanotransduction, with particular impact on the cancer stem cell population. We demonstrate that cell heating results in a robust but temporary loss of cancer cell aggressiveness and metastatic potential in mouse models. In vitro, this heating results in a temporary loss in cell mobility, adhesion, and proliferation. Our hypothesis is that the loss of cellular adhesion results in suppression of cancer stem cells and loss of tumor virulence and metastatic potential. Our study suggests that the metastatic potential of cancer is particularly reduced by the effects of heat on cellular adhesion and mechanotransduction. If true, this could help explain both the successes and failures of clinical hyperthermia, and suggest ways to target treatments to those who would most benefit. - Highlights: • Non-lethal hyperthermia treatment of cancer cells is shown to cause a reduction in rates of tumor initiation and metastasis. • Dynamic imaging of cells during heat treatment shows temporary changes in cell shape, cell migration, and cell proliferation. • Loss of adhesion may lead to the observed effect, which may disproportionately impact the tumor initiating cell fraction. • Loss or suppression of the tumor initiating cell fraction results in the observed loss of metastatic potential in vivo. • This result may lead to new approaches to synergizing hyperthermia with surgery, radiation, and chemotherapy.

  6. Attenuation of auditory evoked potentials for hand and eye-initiated sounds.

    PubMed

    Mifsud, Nathan G; Beesley, Tom; Watson, Tamara L; Whitford, Thomas J

    2016-10-01

    Reduction of auditory event-related potentials (ERPs) to self-initiated sounds has been considered evidence for a predictive model in which copies of motor commands suppress sensory representations of incoming stimuli. However, in studies which involve arbitrary auditory stimuli evoked by sensory-unspecific motor actions, learned associations may underlie ERP differences. Here, in a new paradigm, eye motor output generated auditory sensory input, a naïve action-sensation contingency. We measured the electroencephalogram (EEG) of 40 participants exposed to pure tones, which they produced with either a button-press or volitional saccade. We found that button-press-initiated stimuli evoked reduced amplitude compared to externally initiated stimuli for both the N1 and P2 ERP components, whereas saccade-initiated stimuli evoked intermediate attenuation at N1 and no reduction at P2. These results indicate that the motor-to-sensory mapping involved in speech production may be partly generalized to other contingencies, and that learned associations also contribute to the N1 attenuation effect.

  7. Detonation initiation in solid explosive: MD simulation using AB interatomic potential

    NASA Astrophysics Data System (ADS)

    Murzov, Semen; Zhakhovsky, Vasily

    2015-06-01

    Molecular dynamics simulation of impact detonation initiation in an AB model of condensed-phase explosive is performed with using a simplified reactive empirical bond order potential. Simulation of ultra-short piston-driven compression of AB explosive for the duration of a few picoseconds represents the indirect initiation of detonation by an ultra-short shock wave (SW) generated in a thin metal foil irradiated by a femtosecond laser pulse. Impact conditions required for transition of SW to detonation wave (DW) are studied. Variation of loading time and piston velocity, which controls piston pressure and input energy, is used to plot 2D regions of transition from SW to DW in pressure-time and energy-time planes. We demonstrate that the input energy required for initiation has a global minimum. Analysis of evolution of calculated pressure profiles gives a critical thickness of such AB explosive film in which transition from SW to DW can be completed. The effect of porosity and roughness of AB sample on impact detonation initiation is discussed.

  8. The Initiation of Spike Potential in Barnacle Muscle Fibers under Low Intracellular Ca++

    PubMed Central

    Hagiwara, Susumu; Naka, Ken-ichi

    1964-01-01

    Electrical properties of the muscle fiber membrane were studied in the barnacle, Balanus nubilus Darw. by using intracellular electrode techniques. A depolarization of the membrane does not usually produce an all-or-none spike potential in the normal muscle fiber even though a mechanical response is elicited. The intracellular injection of Ca++-binding agents (K2SO4 and K salt of EDTA solution, K3 citrate solution, etc.) renders the fiber capable of initiating all-or-none spikes. The overshoot of such a spike potential increases with increasing external Ca concentration, the increment for a tenfold increase in Ca concentration being about 29 mv. The threshold membrane potential for the spike and also for the K conductance increase shifts to more positive membrane potentials with increasing [Ca++]out. The removal of Na ions from the external medium does not change the configuration of the spike potential. In the absence of Ca++ in the external medium, the spike potential is restored by Ba++ and Sr++ but not by Mg++. The overshoot of the spike potential increases with increasing [Ba++]out or [Sr++]out. The Ca influx through the membrane of the fiber treated with K2SO4 and EDTA was examined with Ca45. The influx was 14 pmol per sec. per cm2 for the resting membrane and 35 to 85 pmol per cm2 for one spike. From these results it is concluded that the spike potential of the barnacle muscle fiber results from the permeability increase of the membrane to Ca++ (Ba++ or Sr++). PMID:14212145

  9. A potential-energy scaling model to simulate the initial stages of thin-film growth

    NASA Technical Reports Server (NTRS)

    Heinbockel, J. H.; Outlaw, R. A.; Walker, G. H.

    1983-01-01

    A solid on solid (SOS) Monte Carlo computer simulation employing a potential energy scaling technique was used to model the initial stages of thin film growth. The model monitors variations in the vertical interaction potential that occur due to the arrival or departure of selected adatoms or impurities at all sites in the 400 sq. ft. array. Boltzmann ordered statistics are used to simulate fluctuations in vibrational energy at each site in the array, and the resulting site energy is compared with threshold levels of possible atomic events. In addition to adsorption, desorption, and surface migration, adatom incorporation and diffusion of a substrate atom to the surface are also included. The lateral interaction of nearest, second nearest, and third nearest neighbors is also considered. A series of computer experiments are conducted to illustrate the behavior of the model.

  10. Intrasexual competition as a potential influence on anabolic-androgenic steroid use initiation.

    PubMed

    Harris, Marc; Dunn, Michael; Alwyn, Tina

    2017-02-01

    An estimated 293,000 people living in the United Kingdom have used anabolic-androgenic steroids. However, there is currently no intervention to reduce usage available in practice or academic circulation throughout the United Kingdom. This study aimed to test a novel hypothesis that increased levels of intrasexual competition may play an important influential role in the use of anabolic-androgenic steroids. Significantly higher levels of intrasexual competition were evident in users compared to non-users but only in the novice group (0-2 years of experience). The research provides evidence for intrasexual competition potentially influencing anabolic-androgenic steroid use but only during the initial stages of usage.

  11. Early prediction of Biochemical Methane Potential through statistical and kinetic modelling of initial gas production.

    PubMed

    Strömberg, Sten; Nistor, Mihaela; Liu, Jing

    2015-01-01

    A major drawback of Biochemical Methane Potential (BMP) tests is their long test duration, which could be reduced substantially if the final gas production could be predicted at an earlier stage. For this purpose, this study evaluates 61 different algorithms for their capability to predict the final BMP and required degradation time based on data from 138 BMP tests of various substrate types. By combining the best algorithms it was possible to predict the BMP with a relative root mean squared error (rRMSE) of less than 10% just 6days after initiation of the experiment. The results from this study indicate that there is a possibility to shorten the test length substantially by combining laboratory tests and intelligent prediction algorithms. Shorter test duration may widen the possible applications for BMP tests in full-scale biogas plants, allowing for a better selection and proper pricing of biomass.

  12. Small-molecule Hedgehog inhibitor attenuates the leukemia-initiation potential of acute myeloid leukemia cells.

    PubMed

    Fukushima, Nobuaki; Minami, Yosuke; Kakiuchi, Seiji; Kuwatsuka, Yachiyo; Hayakawa, Fumihiko; Jamieson, Catoriona; Kiyoi, Hitoshi; Naoe, Tomoki

    2016-10-01

    Aberrant activation of the Hedgehog signaling pathway has been implicated in the maintenance of leukemia stem cell populations in several model systems. PF-04449913 (PF-913) is a selective, small-molecule inhibitor of Smoothened, a membrane protein that regulates the Hedgehog pathway. However, details of the proof-of-concept and mechanism of action of PF-913 following administration to patients with acute myeloid leukemia (AML) are unclear. This study examined the role of the Hedgehog signaling pathway in AML cells, and evaluated the in vitro and in vivo effects of the Smoothened inhibitor PF-913. In primary AML cells, activation of the Hedgehog signaling pathway was more pronounced in CD34(+) cells than CD34(-) cells. In vitro treatment with PF-913 induced a decrease in the quiescent cell population accompanied by minimal cell death. In vivo treatment with PF-913 attenuated the leukemia-initiation potential of AML cells in a serial transplantation mouse model, while limiting reduction of tumor burden in a primary xenotransplant system. Comprehensive gene set enrichment analysis revealed that PF-913 modulated self-renewal signatures and cell cycle progression. Furthermore, PF-913 sensitized AML cells to cytosine arabinoside, and abrogated resistance to cytosine arabinoside in AML cells cocultured with HS-5 stromal cells. These findings imply that pharmacologic inhibition of Hedgehog signaling attenuates the leukemia-initiation potential, and also enhanced AML therapy by sensitizing dormant leukemia stem cells to chemotherapy and overcoming resistance in the bone marrow microenvironment. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  13. Potential application of LIBS to NNSA next generation safeguards initiative (NGSI)

    SciTech Connect

    Barefield Ii, James E; Clegg, Samuel M; Veirs, Douglas K; Browne, Mike; Lopez, Leon; Martinez, Ron; Le, Loan; Lamontagne, Stephen A

    2009-01-01

    In a climate in which states and nations have been and perhaps currently are involved in the prol iferation of nuclear materials and technologies, advanced methodologies and improvements in current measurement techniques are needed to combat new threats and increased levels of sophistication. The Department of Energy through the National Nuclear Security Administration (NNSA) has undertaken a broad review of International Safeguards. The conclusion from that review was that a comprehensive initiative to revitalize international safeguards technology and the human resource base was urgently needed to keep pace with demands and increasingly sophisticated emerging safeguards challenges. To address these challenges, NNSA launched the Next Generation Safeguards Initiative (NGSI) to develop policies, concepts, technologies, expertise, and infrastructure necessary to sustain the international safeguards system as its mission evolves for the next 25 years. NGSI is designed to revitalize and strengthen the U.S. safeguards technical base, recognizing that without a robust program the United States of America will not be in a position to exercise leadership or provide the necessary support to the IAEA (International Atomic Energy Agency). International safeguards as administrated by the IAEA are the primary vehicle for verifying compliance with the peaceful use and nonproliferation of nuclear materials and technologies. Laser Induced Breakdown Spectroscopy or LIBS has the potential to support the goals of NGSI as follows: by providing (1) automated analysis in complex nuclear processing or reprocessing facilities in real-time or near real-time without sample preparation or removal, (2) isotopic and important elemental ratio (Cm/Pu, Cm/U, ... etc) analysis, and (3) centralized remote control, process monitoring, and analysis of nuclear materials in nuclear facilities at multiple locations within the facility. Potential application of LIBS to international safeguards as

  14. Initial Results from the Floating Potential Measurement Unit aboard the International Space Station

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Swenson, Charles; Thompson, Don; Barjatya, Aroh; Koontz, Steven L.; Schneider, Todd; Vaughn, Jason; Minow, Joseph; Craven, Paul; Coffey, Victoria; Parker, Linda; Bui, Them

    2007-01-01

    The Floating Potential Measurement Unit (FPMU) is a multi-probe package designed to measure the floating potential of the 1nternational Space Station (ISS) as well as the density and temperature of the local ionospheric plasma environment. The role oj the FPMU is to provide direct measurements of ISS spacecraft charging as continuing construction leads to dramatic changes in ISS size and configuration. FPMU data are used for refinement and validation of the ISS spacecraft charging models used to evaluate the severity and frequency of occurrence of ISS charging hazards. The FPMU data and the models are also used to evaluate the effectiveness of proposed hazard controls. The FPMU consists of four probes: a floating potential probe, two Langmuir probes. and a plasma impedance probe. These probes measure the floating potential of the ISS, plasma density, and electron temperature. Redundant measurements using different probes support data validation by inter-probe comparisons. The FPMU was installed by ISS crewmembers, during an ExtraVehicular Activity, on the starboard (Sl) truss of the ISS in early August 2006, when the ISS incorporated only one 160V US photovoltaic (PV) array module. The first data campaign began a few hours after installation and continued for over five days. Additional data campaigns were completed in 2007 after a second 160V US PV array module was added to the ISS. This paper discusses the general performance characteristics of the FPMU as integrated on ISS, the functional performance of each probe, the charging behavior of the ISS before and after the addition of a second 160V US PV array module, and initial results from model comparisons.

  15. Loss of lower limb motor evoked potentials and spinal cord injury during the initial exposure in scoliosis surgery.

    PubMed

    Legatt, Alan D; Fried, Stephen J; Amaral, Terry D; Sarwahi, Vishal; Moguilevitch, Marina

    2014-04-01

    To report a case of motor evoked potential changes and spinal cord injury during the initial dissection in scoliosis surgery. Motor evoked potentials to transcranial electrical stimulation were recorded from multiple muscles. Somatosensory evoked potentials to limb nerve stimulation were recorded from the scalp. Clear motor evoked potentials were initially present in all monitored muscles. The patient was then pharmacologically paralyzed for the initial dissection. More than usual bleeding was encountered during that dissection, prompting transfusion. As the neuromuscular blockade subsided, motor evoked potentials persisted in the hand muscles but disappeared and remained absent in all monitored leg muscles. The spine had not been instrumented. A wake-up test demonstrated paraplegia; the surgery was aborted. There were no adverse somatosensory evoked potential changes. MRI showed an anterior spinal cord infarct. Copious soft tissue bleeding during the initial dissection might have lowered pressures in critical segmental arteries enough to cause spinal cord infarction through a steal phenomenon. The lack of somatosensory evoked potential changes reflected sparing of the dorsal columns. When neuromuscular blockade is used during the initial soft tissue dissection, motor evoked potentials should be assessed after this, but before spinal instrumentation, to determine whether there had been any spinal cord compromise during the initial dissection.

  16. Action potential initiation in the peripheral terminals of cold-sensitive neurones innervating the guinea-pig cornea.

    PubMed

    Carr, Richard W; Pianova, Svetlana; McKemy, David D; Brock, James A

    2009-03-15

    The site at which action potentials initiate within the terminal region of unmyelinated sensory axons has not been resolved. Combining recordings of nerve terminal impulses (NTIs) and collision analysis, the site of action potential initiation in guinea-pig corneal cold receptors was determined. For most receptors (77%), initiation mapped to a point in the time domain that was closer to the nerve terminal than to the site of electrical stimulation at the back of the eye. Guinea-pig corneal cold receptors are Adelta-neurones that lose their myelin sheath at the point where they enter the cornea, and therefore their axons conduct more slowly within the cornea. Allowing for this inhomogeneity in conduction speed, the resulting spatial estimates of action potential initiation sites correlated with changes in NTI shape predicted by simulation of action potentials initiating within a nerve terminal. In some receptors, more than one NTI shape was observed. Simulations of NTI shape suggest that the origin of differing NTI shapes result from action potentials initiating at different, spatially discrete, locations within the nerve terminal. Importantly, the relative incidence of NTI shapes resulting from action potential initiation close to the nerve termination increased during warming when nerve activity decreased, indicating that the favoured site of action potential initiation shifts toward the nerve terminal when it hyperpolarizes. This finding can be explained by a hyperpolarization-induced relief of Na(+) channel inactivation in the nerve terminal. The results provide direct evidence that the molecular entities responsible for stimulus transduction and action potential initiation reside in parallel with one another in the unmyelinated nerve terminals of cold receptors.

  17. Action potential initiation in the peripheral terminals of cold-sensitive neurones innervating the guinea-pig cornea

    PubMed Central

    Carr, Richard W; Pianova, Svetlana; McKemy, David D; Brock, James A

    2009-01-01

    The site at which action potentials initiate within the terminal region of unmyelinated sensory axons has not been resolved. Combining recordings of nerve terminal impulses (NTIs) and collision analysis, the site of action potential initiation in guinea-pig corneal cold receptors was determined. For most receptors (77%), initiation mapped to a point in the time domain that was closer to the nerve terminal than to the site of electrical stimulation at the back of the eye. Guinea-pig corneal cold receptors are Aδ-neurones that lose their myelin sheath at the point where they enter the cornea, and therefore their axons conduct more slowly within the cornea. Allowing for this inhomogeneity in conduction speed, the resulting spatial estimates of action potential initiation sites correlated with changes in NTI shape predicted by simulation of action potentials initiating within a nerve terminal. In some receptors, more than one NTI shape was observed. Simulations of NTI shape suggest that the origin of differing NTI shapes result from action potentials initiating at different, spatially discrete, locations within the nerve terminal. Importantly, the relative incidence of NTI shapes resulting from action potential initiation close to the nerve termination increased during warming when nerve activity decreased, indicating that the favoured site of action potential initiation shifts toward the nerve terminal when it hyperpolarizes. This finding can be explained by a hyperpolarization-induced relief of Na+ channel inactivation in the nerve terminal. The results provide direct evidence that the molecular entities responsible for stimulus transduction and action potential initiation reside in parallel with one another in the unmyelinated nerve terminals of cold receptors. PMID:19171652

  18. Primary dysmenorrhea is potentially predictive for initial orthodontic pain in female patients.

    PubMed

    Ye, Rui; Wang, Sheng; Li, Yu; Wu, Ruixian; Pei, Jiao; Wang, Jue; Zhao, Zhihe

    2014-05-01

    To investigate the relationship between primary dysmenorrhea (PD) and orthodontic pain in female patients, and to test the hypothesis that the intensity and duration of orthodontic pain could be roughly predicted by severity of PD. One hundred twenty college females were enrolled and put into one of three groups-mild (Mi), moderate (Mo), or severe (S)-according to level of menstrual pain. Intensity of the orthodontic pain was measured by visual analog scale (VAS) on days 1, 2, 4, 7, 14, and 28 after archwire placement. As the intensity of orthodontic pain declined with time, the three groups demonstrated different changes during the initial week. Mi had the lowest VAS scores, whereas S possessed the highest scores. In contrast, Mo stayed in between. Significantly positive correlations were found between the severity of PD and the intensity of orthodontic pain at each time point within the first 2 weeks. In addition, though the majority of subjects reported disappearance of pain by the end of the second week in both Mi and Mo, a large proportion of females still perceived pain in S. Females with higher levels of menstrual pain tended to perceive orthodontic pain with higher intensity and more prolonged duration. Thus, PD could potentially serve as a reference to predict orthodontic pain in clinical settings.

  19. Isolation of canine mammary cells with stem cell properties and tumour-initiating potential.

    PubMed

    Cocola, C; Anastasi, P; Astigiano, S; Piscitelli, E; Pelucchi, P; Vilardo, L; Bertoli, G; Beccaglia, M; Veronesi, M C; Sanzone, S; Barbieri, O; Reinbold, R A; Luvoni, G C; Zucchi, I

    2009-07-01

    Recent data suggest that mammary carcinogenesis may be driven by cancer stem cells (CSCs) derived from mutated adult stem cells, which have acquired aberrant cell self-renewal or by progenitor cells that have acquired the capacity for cell self-renewal. Spontaneous mammary cancers in cats and dogs are important models for the understanding of human breast cancer and may represent alternative species model systems that can significantly contribute to the study of human oncogenesis. With the goal of identifying markers for isolating human breast CSCs, we have generated a canine model system to isolate and characterize normal and CSCs from dog mammary gland. Insight into the hierarchical organization of canine tumours may contribute to the development of universal concepts in oncogenesis by CSCs. Cells with stem cell properties were isolated from normal and tumoural canine breast tissue and propagated as mammospheres and tumourspheres in long-term non-adherent culture conditions. We showed that cells obtained from spheres that display self-renewing properties, have multi-lineage differentiation potential, could generate complex branched tubular structures in vitro and form tumours in NOD/SCID mice. We analysed these cells for the expression of human stem and CSC markers and are currently investigating the tumour-initiating properties of these cells and the hierarchical organization of normal and neoplastic canine mammary tissue.

  20. Initial results of bio-potential signal (Seismic Electric Signal) related to seismic activities

    NASA Astrophysics Data System (ADS)

    Kushwah, Vinod; Tiwari, Rudraksh; Gaur, Mulayam; Tiwari, Rajeev

    2013-08-01

    In recent year, there has been growing interest in the possible use of electromagnetic observations to study earthquakes and possible precursors prior to seismic activity, in response to the success in United States, Japan, Russia, China, and other countries using seismo-electromagnetic methods. We have established a new experimental setup (i.e., biopotential sensor) in Farah region (geographic coordinates: 27.17°N, 77.47°E), Mathura, India. The setup has started operating and analyzed the data since November 2011. The data have been tested by various methods and a good correlation with seismic events was found; thus, a real-time analysis from 21:00 p.m. through 8:00 a.m. every day was initiated. First, we recorded the amplitude enhancement in bio-potential and found positive correlation with seismic activities (near Delhi and Rajasthan) and analyzed the data with solar flares and magnetic storms during the same period, finding a negative correlation of these events. The studies of these events are in progress with statistical analysis of the data. We chose the observing site in Farah region because this region is well known for being a site of a conductive channel of seismic activity.

  1. Covariation of axon initial segment location and dendritic tree normalizes the somatic action potential

    PubMed Central

    Hamada, Mustafa S.; Goethals, Sarah; de Vries, Sharon I.; Brette, Romain

    2016-01-01

    In mammalian neurons, the axon initial segment (AIS) electrically connects the somatodendritic compartment with the axon and converts the incoming synaptic voltage changes into a temporally precise action potential (AP) output code. Although axons often emanate directly from the soma, they may also originate more distally from a dendrite, the implications of which are not well-understood. Here, we show that one-third of the thick-tufted layer 5 pyramidal neurons have an axon originating from a dendrite and are characterized by a reduced dendritic complexity and thinner main apical dendrite. Unexpectedly, the rising phase of somatic APs is electrically indistinguishable between neurons with a somatic or a dendritic axon origin. Cable analysis of the neurons indicated that the axonal axial current is inversely proportional to the AIS distance, denoting the path length between the soma and the start of the AIS, and to produce invariant somatic APs, it must scale with the local somatodendritic capacitance. In agreement, AIS distance inversely correlates with the apical dendrite diameter, and model simulations confirmed that the covariation suffices to normalize the somatic AP waveform. Therefore, in pyramidal neurons, the AIS location is finely tuned with the somatodendritic capacitive load, serving as a homeostatic regulation of the somatic AP in the face of diverse neuronal morphologies. PMID:27930291

  2. The Novel Gamma Secretase Inhibitor RO4929097 Reduces the Tumor Initiating Potential of Melanoma

    PubMed Central

    Segura, Miguel F.; Medicherla, Ratna; Haimovic, Adele; Menendez, Silvia; Shang, Shulian; Pavlick, Anna; Shao, Yongzhao; Darvishian, Farbod; Boylan, John F.; Osman, Iman; Hernando, Eva

    2011-01-01

    Several reports have demonstrated a role for aberrant NOTCH signaling in melanoma genesis and progression, prompting us to explore if targeting this pathway is a valid therapeutic approach against melanoma. We targeted NOTCH signaling using RO4929097, a novel inhibitor of gamma secretase, which is a key component of the enzymatic complex that cleaves and activates NOTCH. The effects of RO4929097 on the oncogenic and stem cell properties of a panel of melanoma cell lines were tested both in vitro and in vivo, using xenograft models. In human primary melanoma cell lines, RO4929097 decreased the levels of NOTCH transcriptional target HES1. This was accompanied by reduced proliferation and impaired ability to form colonies in soft agar and to organize in tridimensional spheres. Moreover, RO4929097 affected the growth of human primary melanoma xenograft in NOD/SCID/IL2gammaR-/- mice and inhibited subsequent tumor formation in a serial xenotransplantation model, suggesting that inhibition of NOTCH signaling suppresses the tumor initiating potential of melanoma cells. In addition, RO4929097 decreased tumor volume and blocked the invasive growth pattern of metastatic melanoma cell lines in vivo. Finally, increased gene expression of NOTCH signaling components correlated with shorter post recurrence survival in metastatic melanoma cases. Our data support NOTCH inhibition as a promising therapeutic strategy against melanoma. PMID:21980408

  3. Construction of initial vortex-surface fields and Clebsch potentials for flows with high-symmetry using first integrals

    NASA Astrophysics Data System (ADS)

    He, Pengyu; Yang, Yue

    2016-03-01

    We report a systematic study on the construction of the explicit, general form of vortex-surface fields (VSFs) and Clebsch potentials in the initial fields with the zero helicity density and high symmetry. The construction methodology is based on finding independent first integrals of the characteristic equation of a given three-dimensional velocity-vorticity field. In particular, we derive the analytical VSFs and Clebsch potentials for the initial field with the Kida-Pelz symmetry. These analytical results can be useful for the evolution of VSFs to study vortical structures in transitional flows. Moreover, the generality of the construction method is discussed with the synthetic initial fields and the initial Taylor-Green field with multiple wavenumbers.

  4. The europa initiative for esa's cosmic vision: a potential european contribution to nasa's Europa mission

    NASA Astrophysics Data System (ADS)

    Blanc, Michel; Jones, Geraint H.; Prieto-Ballesteros, Olga; Sterken, Veerle J.

    2016-04-01

    The assessment of the habitability of Jupiter's icy moons is considered of high priority in the roadmaps of the main space agencies, including the decadal survey and esa's cosmic vision plan. the voyager and galileo missions indicated that europa and ganymede may meet the requirements of habitability, including deep liquid aqueous reservoirs in their interiors. indeed, they constitute different end-terms of ocean worlds, which deserve further characterization in the next decade. esa and nasa are now both planning to explore these ice moons through exciting and ambitious missions. esa selected in 2012 the juice mission mainly focused on ganymede and the jupiter system, while nasa is currently studying and implementing the europa mission. in 2015, nasa invited esa to provide a junior spacecraft to be carried on board its europa mission, opening a collaboration scheme similar to the very successful cassini-huygens approach. in order to define the best contribution that can be made to nasa's europa mission, a europa initiative has emerged in europe. its objective is to elaborate a community-based strategy for the proposition of the best possible esa contribution(s) to nasa's europa mission, as a candidate for the upcoming selection of esa's 5th medium-class mission . the science returns of the different potential contributions are analysed by six international working groups covering complementary science themes: a) magnetospheric interactions; b) exosphere, including neutrals, dust and plumes; c) geochemistry; d) geology, including expressions of exchanges between layers; e) geophysics, including characterization of liquid water distribution; f) astrobiology. each group is considering different spacecraft options in the contexts of their main scientific merits and limitations, their technical feasibility, and of their interest for the development of esa-nasa collaborations. there are five options under consideration: (1) an augmented payload to the europa mission main

  5. Chapter 2: Assessing the Potential Energy Impacts of Clean Energy Initiatives

    EPA Pesticide Factsheets

    “Assessing the Multiple Benefits of Clean Energy” helps state energy, environmental, and economic policy makers identify and quantify the many benefits of clean energy to support the development and implementation of cost-effective clean energy initiatives

  6. Chapter 2: Assessing the Potential Energy Impacts of Clean Energy Initiatives

    EPA Pesticide Factsheets

    Assessing the Multiple Benefits of Clean Energy” helps state energy, environmental, and economic policy makers identify and quantify the many benefits of clean energy to support the development and implementation of cost-effective clean energy initiatives

  7. Estimating Renewable Energy Economic Potential in the United States: Methodology and Initial Results

    SciTech Connect

    Brown, Austin; Beiter, Philipp; Heimiller, Donna; Davidson, Carolyn; Denholm, Paul; Melius, Jennifer; Lopez, Anthony; Hettinger, Dylan; Mulcahy, David; Porro, Gian

    2016-08-01

    The report describes a geospatial analysis method to estimate the economic potential of several renewable resources available for electricity generation in the United States. Economic potential, one measure of renewable generation potential, is defined in this report as the subset of the available resource technical potential where the cost required to generate the electricity (which determines the minimum revenue requirements for development of the resource) is below the revenue available in terms of displaced energy and displaced capacity.

  8. Using Empirical Data to Estimate Potential Functions in Commodity Markets: Some Initial Results

    NASA Astrophysics Data System (ADS)

    Shen, C.; Haven, E.

    2017-07-01

    This paper focuses on estimating real and quantum potentials from financial commodities. The log returns of six common commodities are considered. We find that some phenomena, such as the vertical potential walls and the time scale issue of the variation on returns, also exists in commodity markets. By comparing the quantum and classical potentials, we attempt to demonstrate that the information within these two types of potentials is different. We believe this empirical result is consistent with the theoretical assumption that quantum potentials (when embedded into social science contexts) may contain some social cognitive or market psychological information, while classical potentials mainly reflect `hard' market conditions. We also compare the two potential forces and explore their relationship by simply estimating the Pearson correlation between them. The Medium or weak interaction effect may indicate that the cognitive system among traders may be affected by those `hard' market conditions.

  9. Effects of applied potential and the initial gap between electrodes on localized electrochemical deposition of micrometer copper columns

    NASA Astrophysics Data System (ADS)

    Wang, Fuliang; Xiao, Hongbin; He, Hu

    2016-05-01

    Micrometer copper columns were fabricated via a technology named localized electrochemical deposition (LECD). This paper studies the effects of applied potential and the initial gap between electrodes on the LECD process. The surface and cross sectional morphologies, as well as the average deposition rate were investigated to evaluate the quality of the deposited copper columns. Results demonstrated that the copper columns tended to be cylinder-shape with few voids inside at lower potential (<2.4 V). Whereas,the copper columns tended to be dendriform-shape with lots of voids inside at larger potential (>2.8 V). The average deposition rate increased with the raise of potential. In addition, the copper columns tended to be cylinder-shape with the initial gap between electrodes to be 10 μm or below. However, the copper columns tended to be cone-shape when the initial gap between electrodes became larger (35 μm or above). The number of voids inside the copper column and the average deposition rate both decreased with the increase of the initial gap. Moreover, the process of LECD under varied electric field has also been simulated using COMSOL software, and the formation of cylindrical and conical copper columns was further explained based on the electric field distribution at the cathode.

  10. Effects of applied potential and the initial gap between electrodes on localized electrochemical deposition of micrometer copper columns

    PubMed Central

    Wang, Fuliang; Xiao, Hongbin; He, Hu

    2016-01-01

    Micrometer copper columns were fabricated via a technology named localized electrochemical deposition (LECD). This paper studies the effects of applied potential and the initial gap between electrodes on the LECD process. The surface and cross sectional morphologies, as well as the average deposition rate were investigated to evaluate the quality of the deposited copper columns. Results demonstrated that the copper columns tended to be cylinder-shape with few voids inside at lower potential (<2.4 V). Whereas,the copper columns tended to be dendriform-shape with lots of voids inside at larger potential (>2.8 V). The average deposition rate increased with the raise of potential. In addition, the copper columns tended to be cylinder-shape with the initial gap between electrodes to be 10 μm or below. However, the copper columns tended to be cone-shape when the initial gap between electrodes became larger (35 μm or above). The number of voids inside the copper column and the average deposition rate both decreased with the increase of the initial gap. Moreover, the process of LECD under varied electric field has also been simulated using COMSOL software, and the formation of cylindrical and conical copper columns was further explained based on the electric field distribution at the cathode. PMID:27185742

  11. Multi-Point E-Conferencing with Initial Teacher Training Students in England: Pitfalls and Potential

    ERIC Educational Resources Information Center

    Pratt, Nick

    2008-01-01

    This article reports on attempts to initiate multi-point e-conferencing between English teacher education students on school placements, their host teachers and their university tutors. A sociocultural perspective is adopted in analysing the project, using the metaphor of a "professional knowledge landscape" [Clandinin, D. J., &…

  12. Evaluation of the Initiation/Promotion Potential of CTFE Trimer Acid

    DTIC Science & Technology

    1990-11-01

    Chlorotrifluoroethylene Trimer Acid Hepatocarcinogenesis 43 Initiation Perhalogenated Fatty Acid 16. PRICE CODE Peroxisome Proliferator Promotion 17...peroxisomal proliferation. Several peroxisome proliferators have been shown to inhibit mitochondrial fatty acid oxidation in rat liver (Bone et al., 1982...in the fatty acid oxidase system (Harrison et al., 1988). These findings and the fact that mammals can oxidize n-alkanes to the corresponding fatty

  13. Multi-Point E-Conferencing with Initial Teacher Training Students in England: Pitfalls and Potential

    ERIC Educational Resources Information Center

    Pratt, Nick

    2008-01-01

    This article reports on attempts to initiate multi-point e-conferencing between English teacher education students on school placements, their host teachers and their university tutors. A sociocultural perspective is adopted in analysing the project, using the metaphor of a "professional knowledge landscape" [Clandinin, D. J., &…

  14. Estimating Renewable Energy Economic Potential in the United States. Methodology and Initial Results

    SciTech Connect

    Brown, Austin; Beiter, Philipp; Heimiller, Donna; Davidson, Carolyn; Denholm, Paul; Melius, Jennifer; Lopez, Anthony; Hettinger, Dylan; Mulcahy, David; Porro, Gian

    2016-08-01

    This report describes a geospatial analysis method to estimate the economic potential of several renewable resources available for electricity generation in the United States. Economic potential, one measure of renewable generation potential, may be defined in several ways. For example, one definition might be expected revenues (based on local market prices) minus generation costs, considered over the expected lifetime of the generation asset. Another definition might be generation costs relative to a benchmark (e.g., a natural gas combined cycle plant) using assumptions of fuel prices, capital cost, and plant efficiency. Economic potential in this report is defined as the subset of the available resource technical potential where the cost required to generate the electricity (which determines the minimum revenue requirements for development of the resource) is below the revenue available in terms of displaced energy and displaced capacity. The assessment is conducted at a high geospatial resolution (more than 150,000 technology-specific sites in the continental United States) to capture the significant variation in local resource, costs, and revenue potential. This metric can be a useful screening factor for understanding the economic viability of renewable generation technologies at a specific location. In contrast to many common estimates of renewable energy potential, economic potential does not consider market dynamics, customer demand, or most policy drivers that may incent renewable energy generation.

  15. Matrix Metalloproteinase-10 Is Required for Lung Cancer Stem Cell Maintenance, Tumor Initiation and Metastatic Potential

    PubMed Central

    Tseng, I-Chu; Walsh, Michael P.; Batra, Jyotica; Radisky, Evette S.; Murray, Nicole R.; Fields, Alan P.

    2012-01-01

    Matrix metalloproteinases (Mmps) stimulate tumor invasion and metastasis by degrading the extracellular matrix. Here we reveal an unexpected role for Mmp10 (stromelysin 2) in the maintenance and tumorigenicity of mouse lung cancer stem-like cells (CSC). Mmp10 is highly expressed in oncosphere cultures enriched in CSCs and RNAi-mediated knockdown of Mmp10 leads to a loss of stem cell marker gene expression and inhibition of oncosphere growth, clonal expansion, and transformed growth in vitro. Interestingly, clonal expansion of Mmp10 deficient oncospheres can be restored by addition of exogenous Mmp10 protein to the culture medium, demonstrating a direct role for Mmp10 in the proliferation of these cells. Oncospheres exhibit enhanced tumor-initiating and metastatic activity when injected orthotopically into syngeneic mice, whereas Mmp10-deficient cultures show a severe defect in tumor initiation. Conversely, oncospheres implanted into syngeneic non-transgenic or Mmp10−/− mice show no significant difference in tumor initiation, growth or metastasis, demonstrating the importance of Mmp10 produced by cancer cells rather than the tumor microenvironment in lung tumor initiation and maintenance. Analysis of gene expression data from human cancers reveals a strong positive correlation between tumor Mmp10 expression and metastatic behavior in many human tumor types. Thus, Mmp10 is required for maintenance of a highly tumorigenic, cancer-initiating, metastatic stem-like cell population in lung cancer. Our data demonstrate for the first time that Mmp10 is a critical lung cancer stem cell gene and novel therapeutic target for lung cancer stem cells. PMID:22545096

  16. The ORYX initiative: goals and potential application to physician quality improvement efforts.

    PubMed

    Hanold, L S; Koss, R G; Loeb, J M

    2000-10-01

    Demands for public accountability in health care are more widespread today than at any time in the past. A number of national performance measurement efforts, including the ORYX initiative of the Joint Commission on Accreditation of Healthcare Organizations, represent an effort to provide stakeholders with the data they need to make judgments about the quality of health care provided to the public. The underlying premise of performance measurement is that organizations and clinicians can only improve what they can measure. Clinicians are the natural leaders in effecting broad-based change because of their direct influence on patient care and the respect they command in the health care environment. As performance measurement initiatives evolve, the ability of health care organizations to implement empirically based, structured improvement will increase and become commonplace.

  17. Heteromeric Kv7.2/7.3 channels differentially regulate action potential initiation and conduction in neocortical myelinated axons.

    PubMed

    Battefeld, Arne; Tran, Baouyen T; Gavrilis, Jason; Cooper, Edward C; Kole, Maarten H P

    2014-03-05

    Rapid energy-efficient signaling along vertebrate axons is achieved through intricate subcellular arrangements of voltage-gated ion channels and myelination. One recently appreciated example is the tight colocalization of K(v)7 potassium channels and voltage-gated sodium (Na(v)) channels in the axonal initial segment and nodes of Ranvier. The local biophysical properties of these K(v)7 channels and the functional impact of colocalization with Na(v) channels remain poorly understood. Here, we quantitatively examined K(v)7 channels in myelinated axons of rat neocortical pyramidal neurons using high-resolution confocal imaging and patch-clamp recording. K(v)7.2 and 7.3 immunoreactivity steeply increased within the distal two-thirds of the axon initial segment and was mirrored by the conductance density estimates, which increased from ~12 (proximal) to 150 pS μm(-2) (distal). The axonal initial segment and nodal M-currents were similar in voltage dependence and kinetics, carried by K(v)7.2/7.3 heterotetramers, 4% activated at the resting membrane potential and rapidly activated with single-exponential time constants (~15 ms at 28 mV). Experiments and computational modeling showed that while somatodendritic K(v)7 channels are strongly activated by the backpropagating action potential to attenuate the afterdepolarization and repetitive firing, axonal K(v)7 channels are minimally recruited by the forward-propagating action potential. Instead, in nodal domains K(v)7.2/7.3 channels were found to increase Na(v) channel availability and action potential amplitude by stabilizing the resting membrane potential. Thus, K(v)7 clustering near axonal Na(v) channels serves specific and context-dependent roles, both restraining initiation and enhancing conduction of the action potential.

  18. Heteromeric Kv7.2/7.3 Channels Differentially Regulate Action Potential Initiation and Conduction in Neocortical Myelinated Axons

    PubMed Central

    Battefeld, Arne; Tran, Baouyen T.; Gavrilis, Jason; Cooper, Edward C.

    2014-01-01

    Rapid energy-efficient signaling along vertebrate axons is achieved through intricate subcellular arrangements of voltage-gated ion channels and myelination. One recently appreciated example is the tight colocalization of Kv7 potassium channels and voltage-gated sodium (Nav) channels in the axonal initial segment and nodes of Ranvier. The local biophysical properties of these Kv7 channels and the functional impact of colocalization with Nav channels remain poorly understood. Here, we quantitatively examined Kv7 channels in myelinated axons of rat neocortical pyramidal neurons using high-resolution confocal imaging and patch-clamp recording. Kv7.2 and 7.3 immunoreactivity steeply increased within the distal two-thirds of the axon initial segment and was mirrored by the conductance density estimates, which increased from ∼12 (proximal) to 150 pS μm−2 (distal). The axonal initial segment and nodal M-currents were similar in voltage dependence and kinetics, carried by Kv7.2/7.3 heterotetramers, 4% activated at the resting membrane potential and rapidly activated with single-exponential time constants (∼15 ms at 28 mV). Experiments and computational modeling showed that while somatodendritic Kv7 channels are strongly activated by the backpropagating action potential to attenuate the afterdepolarization and repetitive firing, axonal Kv7 channels are minimally recruited by the forward-propagating action potential. Instead, in nodal domains Kv7.2/7.3 channels were found to increase Nav channel availability and action potential amplitude by stabilizing the resting membrane potential. Thus, Kv7 clustering near axonal Nav channels serves specific and context-dependent roles, both restraining initiation and enhancing conduction of the action potential. PMID:24599470

  19. Translation of chloroplast-encoded mRNA: potential initiation and termination signals.

    PubMed Central

    Bonham-Smith, P C; Bourque, D P

    1989-01-01

    A survey of 196 protein-coding chloroplast DNA sequences demonstrated the preference for AUG and UAA codons for initiation and termination of translation, respectively. As in prokaryotes at every nucleotide position from -25 to +25 (AUG is +1 to +3) and for 25 nucleotides 5' and 3' to the termination codon an A or U is predominant, except for C at +5 and G at +22. A Shine-Dalgarno (SD) sequence (GGAGG or tri- or tetranucleotide variant) was found within 100 bp 5' to the AUG codon in 92% of the genes. In 40% of these cases, the location of the SD sequence was similar to that of the consensus for prokaryotes (-12 to -7 5' to AUG), presumed to be optimal for translation initiation. A SD sequence could not be located in 6% of the chloroplast sequences. We propose that mRNA secondary structures may be required for the relocation of a distal SD sequences to within the optimal region (-12 to -7) for initiation of translation. We further suggest that termination at UGA codons in chloroplast genes may occur by a mechanism, involving 16S rRNA secondary structure, which has been proposed for UGA termination in E. coli. PMID:2928114

  20. The spatio-temporal characteristics of action potential initiation in layer 5 pyramidal neurons: a voltage imaging study

    PubMed Central

    Popovic, Marko A; Foust, Amanda J; McCormick, David A; Zecevic, Dejan

    2011-01-01

    Abstract The spatial pattern of Na+ channel clustering in the axon initial segment (AIS) plays a critical role in tuning neuronal computations, and changes in Na+ channel distribution have been shown to mediate novel forms of neuronal plasticity in the axon. However, immunocytochemical data on channel distribution may not directly predict spatio-temporal characteristics of action potential initiation, and prior electrophysiological measures are either indirect (extracellular) or lack sufficient spatial resolution (intracellular) to directly characterize the spike trigger zone (TZ). We took advantage of a critical methodological improvement in the high sensitivity membrane potential imaging (Vm imaging) technique to directly determine the location and length of the spike TZ as defined in functional terms. The results show that in mature axons of mouse cortical layer 5 pyramidal cells, action potentials initiate in a region ∼20 μm in length centred between 20 and 40 μm from the soma. From this region, the AP depolarizing wave invades initial nodes of Ranvier within a fraction of a millisecond and propagates in a saltatory fashion into axonal collaterals without failure at all physiologically relevant frequencies. We further demonstrate that, in contrast to the saltatory conduction in mature axons, AP propagation is non-saltatory (monotonic) in immature axons prior to myelination. PMID:21669974

  1. Morphological Characterization of the Action Potential Initiation Segment in GnRH Neuron Dendrites and Axons of Male Mice.

    PubMed

    Herde, Michel K; Herbison, Allan E

    2015-11-01

    GnRH neurons are the final output neurons of the hypothalamic network controlling fertility in mammals. In the present study, we used ankyrin G immunohistochemistry and neurobiotin filling of live GnRH neurons in brain slices from GnRH-green fluorescent protein transgenic male mice to examine in detail the location of action potential initiation in GnRH neurons with somata residing at different locations in the basal forebrain. We found that the vast majority of GnRH neurons are bipolar in morphology, elaborating a thick (primary) and thinner (secondary) dendrite from opposite poles of the soma. In addition, an axon-like process arising predominantly from a proximal dendrite was observed in a subpopulation of GnRH neurons. Ankyrin G immunohistochemistry revealed the presence of a single action potential initiation zone ∼27 μm in length primarily in the secondary dendrite of GnRH neurons and located 30 to 140 μm distant from the cell soma, depending on the type of process and location of the cell body. In addition to dendrites, the GnRH neurons with cell bodies located close to hypothalamic circumventricular organs often elaborated ankyrin G-positive axon-like structures. Almost all GnRH neurons (>90%) had their action potential initiation site in a process that initially, or ultimately after a hairpin loop, was coursing in the direction of the median eminence. These studies indicate that action potentials are initiated in different dendritic and axonal compartments of the GnRH neuron in a manner that is dependent partly on the neuroanatomical location of the cell body.

  2. On the initial conditions for inflation with plateau potentials: the R+R{sup 2} (super)gravity case

    SciTech Connect

    Dalianis, Ioannis; Farakos, Fotis E-mail: fotisf@mail.muni.cz

    2015-07-01

    We discuss the initial conditions problem for inflation driven by the vacuum energy of a plateau potential, and in particular the Starobinsky inflation. We show that the supergravity embedding of the R+R{sup 2} theory naturally decreases the size of the acausal homogeneity, required for the low-scale inflation to occur, thanks to the presence of the dynamical pure supergravitational ''auxiliary'' fields. We examine the evolution of the R+R{sup 2} fields within a FLRW Universe. We also find a dependence of the initial conditions problem on the background spatial curvature.

  3. CK2 phosphorylation of eukaryotic translation initiation factor 5 potentiates cell cycle progression

    PubMed Central

    Homma, Miwako Kato; Wada, Ikuo; Suzuki, Toshiyuki; Yamaki, Junko; Krebs, Edwin G.; Homma, Yoshimi

    2005-01-01

    Casein kinase 2 (CK2) is a ubiquitous eukaryotic Ser/Thr protein kinase that plays an important role in cell cycle progression. Although its function in this process remains unclear, it is known to be required for the G1 and G2/M phase transitions in yeast. Here, we show that CK2 activity changes notably during cell cycle progression and is increased within 3 h of serum stimulation of quiescent cells. During the time period in which it exhibits high enzymatic activity, CK2 associates with and phosphorylates a key molecule for translation initiation, eukaryotic translation initiation factor (eIF) 5. Using MS, we show that Ser-389 and -390 of eIF5 are major sites of phosphorylation by CK2. This is confirmed using eIF5 mutants that lack CK2 sites; the phosphorylation levels of mutant eIF5 proteins are significantly reduced, relative to WT eIF5, both in vitro and in vivo. Expression of these mutants reveals that they have a dominant-negative effect on phosphorylation of endogenous eIF5, and that they perturb synchronous progression of cells through S to M phase, resulting in a significant reduction in growth rate. Furthermore, the formation of mature eIF5/eIF2/eIF3 complex is reduced in these cells, and, in fact, restricted diffusional motion of WT eIF5 was almost abolished in a GFP-tagged eIF5 mutant lacking CK2 phosphorylation sites, as measured by fluorescence correlation spectroscopy. These results suggest that CK2 may be involved in the regulation of cell cycle progression by associating with and phosphorylating a key molecule for translation initiation. PMID:16227438

  4. [Potentials of cooperative quality management initiatives: BQS Institute projects, January 2010 - July 2013].

    PubMed

    Veit, Christof; Bungard, Sven; Hertle, Dagmar; Grothaus, Franz-Josef; Kötting, Joachim; Arnold, Nicolai

    2013-01-01

    Alongside the projects of internal quality management and mandatory quality assurance there is a variety of quality driven projects across institutions initiated and run by various partners to continuously improve the quality of care. The multiplicity and characteristics of these projects are discussed on the basis of projects run by the BQS Institute between 2010 and 2013. In addition, useful interactions and linking with mandatory quality benchmarking and with internal quality management are discussed. (As supplied by publisher). Copyright © 2013. Published by Elsevier GmbH.

  5. The Floating Potential Probe (FPP) for ISS: Operations and Initial Results

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.; Hillard, G. Barry; Morton, Thomas L.

    2001-01-01

    In this paper we report early results from the Floating Potential Probe (FPP) recently installed on the International Space Station (ISS). The data show that FPP properly measures the electrical potential of ISS structure with respect to the plasma it is flying through. FPP Langmuir probe data seem to give accurate measurements of the ambient plasma density, and are generally consistent with the IRI-90 model. FPP data are used to judge the performance of the ISS Plasma Contacting Units (PCUs), and to evaluate the extent of ISS charging in the absence of the PCUs.

  6. Zinc inhibits protein synthesis in neurons. Potential role of phosphorylation of translation initiation factor-2alpha.

    PubMed

    Alirezaei, M; Nairn, A C; Glowinski, J; Prémont, J; Marin, P

    1999-11-05

    In the central nervous system, Zn(2+) is concentrated in the cerebral cortex and hippocampus and has been found to be toxic to neurons. In this study, we show that exposure of cultured cortical neurons from mouse to increasing concentrations of Zn(2+) (10-300 microM) induces a progressive decrease in global protein synthesis. The potency of Zn(2+) was increased by about 2 orders of magnitude in the presence of Na(+)-pyrithione, a Zn(2+) ionophore. The basal rate of protein synthesis was restored 3 h after Zn(2+) removal. Zn(2+) induced a sustained increase in phosphorylation of the alpha subunit of the translation eukaryotic initiation factor-2 (eIF-2alpha), whereas it triggered a transient increase in phosphorylation of eukaryotic elongation factor-2 (eEF-2). Protein synthesis was still depressed 60 min after the onset of Zn(2+) exposure while the state of eEF-2 phosphorylation had already returned to its basal level. Moreover, Zn(2+) was less effective than glutamate to increase eEF-2 phosphorylation, whereas it induced a more profound inhibition of protein synthesis. These results suggest that Zn(2+)-induced inhibition of protein synthesis mainly correlates with the increase in eIF-2alpha phosphorylation. Supporting further that Zn(2+) acts at the initiation step of protein synthesis, it strongly decreased the amount of polyribosomes.

  7. H+CH4 → H2 + CH3 initial state-selected reaction probabilities on different potential energy surfaces

    NASA Astrophysics Data System (ADS)

    Ellerbrock, Roman; Manthe, Uwe

    2017-01-01

    Initial state-selected reaction probabilities for the H +CH4 →H2 +CH3 reaction on a recently developed potential energy surface which employs neutral network fitting based on permutational invariant polynomials are reported. The quantum dynamics calculations use the quantum transition state concept and the multi-layer multi-configurational time-dependent Hartree approach and study the reaction process in full-dimensionality for vanishing total angular momentum. A detailed comparison with previous results obtained on other high-level potential energy surfaces is given. The connection between the level of quantum state resolution and the sensitivity of the results on differences in the potential energy surfaces is highlighted. Employing a decomposition of the total reactivity into contributions of the different vibrational states of the activated complex, it is found that differences between the potential energy surfaces are mainly related to the umbrella motion of the methyl group.

  8. Risk Factors for Initiation of Potentially Inappropriate Medications in Community-Dwelling Older Adults with and without Alzheimer's Disease.

    PubMed

    Hyttinen, Virva; Taipale, Heidi; Tanskanen, Antti; Tiihonen, Jari; Tolppanen, Anna-Maija; Hartikainen, Sirpa; Valtonen, Hannu

    2017-01-01

    Various criteria have been created to define potentially inappropriate medications (PIMs) to help improve the quality and safety of medicine use in older patients. Individuals with Alzheimer's disease (AD) may be at higher risk of adverse drug events associated with PIMs (such as falls). Our objective was to determine the risk factors for PIM initiation in a nationwide cohort of community dwellers aged ≥65 years with and without AD. The Finnish nationwide MEDALZ cohort includes all patients diagnosed with AD in 2005-2011 (n = 70,718) and two comparison individuals without AD (non-AD) matched for age, sex and region of residence for each person with AD. After a 1-year washout period for PIM use and exclusion of those aged <65 years, we included 50,494 patients with AD and 106,306 comparison subjects. PIM use was defined according to Finnish criteria. Subjects without AD initiated PIMs more frequently than those with AD (16.4 vs. 12.2%, respectively; p < 0.001). The most common PIMs were muscle relaxants and urinary antispasmodics. Older individuals (aged ≥75 years) were less likely to initiate PIMs. In the AD group, women were less likely to initiate PIMs than men. More comorbidities were associated with PIM initiation, especially in the non-AD group. The use of opioids or psychotropic medicines was associated with PIM initiation in both cohorts. Regional differences between university hospital districts were observed. PIM initiation was dependent on patient characteristics and possibly also some healthcare system-related factors such as differing regional treatment practices. It is important that medicines prescribed to the older vulnerable population are assessed regularly to avoid adverse effects and ensure safe pharmacotherapy, especially in those with multiple comorbidities.

  9. Recessive Resistance to Plant Viruses: Potential Resistance Genes Beyond Translation Initiation Factors.

    PubMed

    Hashimoto, Masayoshi; Neriya, Yutaro; Yamaji, Yasuyuki; Namba, Shigetou

    2016-01-01

    The ability of plant viruses to propagate their genomes in host cells depends on many host factors. In the absence of an agrochemical that specifically targets plant viral infection cycles, one of the most effective methods for controlling viral diseases in plants is taking advantage of the host plant's resistance machinery. Recessive resistance is conferred by a recessive gene mutation that encodes a host factor critical for viral infection. It is a branch of the resistance machinery and, as an inherited characteristic, is very durable. Moreover, recessive resistance may be acquired by a deficiency in a negative regulator of plant defense responses, possibly due to the autoactivation of defense signaling. Eukaryotic translation initiation factor (eIF) 4E and eIF4G and their isoforms are the most widely exploited recessive resistance genes in several crop species, and they are effective against a subset of viral species. However, the establishment of efficient, recessive resistance-type antiviral control strategies against a wider range of plant viral diseases requires genetic resources other than eIF4Es. In this review, we focus on recent advances related to antiviral recessive resistance genes evaluated in model plants and several crop species. We also address the roles of next-generation sequencing and genome editing technologies in improving plant genetic resources for recessive resistance-based antiviral breeding in various crop species.

  10. The Potentials of Student Initiated Netspeak in a Middle Primary Science-inspired Multiliteracies Project

    NASA Astrophysics Data System (ADS)

    Ridgewell, Jay; Exley, Beryl

    2011-11-01

    There is no denying that the information technology revolution of the late twentieth century has arrived. Whilst not equitably accessible for many, others hold high expectations for the contributions online activity will make to student learning outcomes. Concurrently, and not necessarily consequentially, the number of science and technology secondary school and university graduates throughout the world has declined substantially, as has their motivation and engagement with school science (OECD 2006). The aim of this research paper is to explore one aspect of online activity, that of forum-based netspeak (Crystal 2006), in relation to the possibilities and challenges it provides for forms of scientific learning. This paper reports findings from a study investigating student initiated netspeak in a science inspired multiliteracies (New London Group 2000) project in one middle primary (aged 7-10 years) multi-age Australian classroom. Drawing on the theoretical description of the five phases of enquiry proposed by Bybee (1997), an analytic framework is proffered that allows identification of student engagement, exploration, explanation, elaboration and evaluation of scientific enquiry. The findings provide insight into online forums for advancing learning in, and motivation for, science in the middle primary years.

  11. Recessive Resistance to Plant Viruses: Potential Resistance Genes Beyond Translation Initiation Factors

    PubMed Central

    Hashimoto, Masayoshi; Neriya, Yutaro; Yamaji, Yasuyuki; Namba, Shigetou

    2016-01-01

    The ability of plant viruses to propagate their genomes in host cells depends on many host factors. In the absence of an agrochemical that specifically targets plant viral infection cycles, one of the most effective methods for controlling viral diseases in plants is taking advantage of the host plant’s resistance machinery. Recessive resistance is conferred by a recessive gene mutation that encodes a host factor critical for viral infection. It is a branch of the resistance machinery and, as an inherited characteristic, is very durable. Moreover, recessive resistance may be acquired by a deficiency in a negative regulator of plant defense responses, possibly due to the autoactivation of defense signaling. Eukaryotic translation initiation factor (eIF) 4E and eIF4G and their isoforms are the most widely exploited recessive resistance genes in several crop species, and they are effective against a subset of viral species. However, the establishment of efficient, recessive resistance-type antiviral control strategies against a wider range of plant viral diseases requires genetic resources other than eIF4Es. In this review, we focus on recent advances related to antiviral recessive resistance genes evaluated in model plants and several crop species. We also address the roles of next-generation sequencing and genome editing technologies in improving plant genetic resources for recessive resistance-based antiviral breeding in various crop species. PMID:27833593

  12. Molecular hydrogen as a preventive and therapeutic medical gas: initiation, development and potential of hydrogen medicine.

    PubMed

    Ohta, Shigeo

    2014-10-01

    Molecular hydrogen (H2) has been accepted to be an inert and nonfunctional molecule in our body. We have turned this concept by demonstrating that H2 reacts with strong oxidants such as hydroxyl radical in cells, and proposed its potential for preventive and therapeutic applications. H2 has a number of advantages exhibiting extensive effects: H2 rapidly diffuses into tissues and cells, and it is mild enough neither to disturb metabolic redox reactions nor to affect signaling reactive oxygen species; therefore, there should be no or little adverse effects of H2. There are several methods to ingest or consume H2; inhaling H2 gas, drinking H2-dissolved water (H2-water), injecting H2-dissolved saline (H2-saline), taking an H2 bath, or dropping H2-saline into the eyes. The numerous publications on its biological and medical benefits revealed that H2 reduces oxidative stress not only by direct reactions with strong oxidants, but also indirectly by regulating various gene expressions. Moreover, by regulating the gene expressions, H2 functions as an anti-inflammatory and anti-apoptotic, and stimulates energy metabolism. In addition to growing evidence obtained by model animal experiments, extensive clinical examinations were performed or are under investigation. Since most drugs specifically act to their targets, H2 seems to differ from conventional pharmaceutical drugs. Owing to its great efficacy and lack of adverse effects, H2 has promising potential for clinical use against many diseases.

  13. The impact of age on oncogenic potential: tumor-initiating cells and the brain microenvironment.

    PubMed

    Stoll, Elizabeth A; Horner, Philip J; Rostomily, Robert C

    2013-10-01

    Paradoxically, aging leads to both decreased regenerative capacity in the brain and an increased risk of tumorigenesis, particularly the most common adult-onset brain tumor, glioma. A shared factor contributing to both phenomena is thought to be age-related alterations in neural progenitor cells (NPCs), which function normally to produce new neurons and glia, but are also considered likely cells of origin for malignant glioma. Upon oncogenic transformation, cells acquire characteristics known as the hallmarks of cancer, including unlimited replication, altered responses to growth and anti-growth factors, increased capacity for angiogenesis, potential for invasion, genetic instability, apoptotic evasion, escape from immune surveillance, and an adaptive metabolic phenotype. The precise molecular pathogenesis and temporal acquisition of these malignant characteristics is largely a mystery. Recent studies characterizing NPCs during normal aging, however, have begun to elucidate mechanisms underlying the age-associated increase in their malignant potential. Aging cells are dependent upon multiple compensatory pathways to maintain cell cycle control, normal niche interactions, genetic stability, programmed cell death, and oxidative metabolism. A few multi-functional proteins act as 'critical nodes' in the coordination of these various cellular activities, although both intracellular signaling and elements within the brain environment are critical to maintaining a balance between senescence and tumorigenesis. Here, we provide an overview of recent progress in our understanding of how mechanisms underlying cellular aging inform on glioma pathogenesis and malignancy.

  14. Hueco tanks: an initial evaluation of a potential geothermal area near El Paso, Texas

    SciTech Connect

    Taylor, B.; Roy, R.F.; Hoffer, J.M.

    1980-09-01

    A potential geothermal resource about 40km northeast of El Paso, Texas is under investigation. The presence of old hot wells indicated the area of interest, and a geochemical survey outlined the possible geothermal anomaly. A shallow drilling program has revealed gradients consistently over 100/sup 0/C/km and as high as 300/sup 0/C/km on the Texas side of the state line, and a 300m hole yielded a heat flow of 8.3 H.F.U. in the limestone bedrock. Electrical soundings have shown the presence of a shallow conductive layer (probably hot and/or mineralized water) and a recently completed gravity survey delineates the faulting pattern apparently responsbile for the uprise of thermal waters. Indications are presently not for an electricity-grade resource, but of a hot water reservoir, with temperatures maybe reaching 120 to 140/sup 0/C.

  15. Na+ current in presynaptic terminals of the crayfish opener cannot initiate action potentials

    PubMed Central

    2015-01-01

    Action potential (AP) propagation in presynaptic axons of the crayfish opener neuromuscular junction (NMJ) was investigated by simultaneously recording from a terminal varicosity and a proximal branch. Although orthodromically conducting APs could be recorded in terminals with amplitudes up to 70 mV, depolarizing steps in terminals to −20 mV or higher failed to fire APs. Patch-clamp recordings did detect Na+ current (INa) in most terminals. The INa exhibited a high threshold and fast activation rate. Local perfusion of Na+-free saline showed that terminal INa contributed to AP waveform by slightly accelerating the rising phase and increasing the peak amplitude. These findings suggest that terminal INa functions to “touch up” but not to generate APs. PMID:26561611

  16. Initial Investigation into the Potential of CSP Industrial Process Heat for the Southwest United States

    SciTech Connect

    Kurup, Parthiv; Turchi, Craig

    2015-11-01

    After significant interest in the 1970s, but relatively few deployments, the use of solar technologies for thermal applications, including enhanced oil recovery (EOR), desalination, and industrial process heat (IPH), is again receiving global interest. In particular, the European Union (EU) has been a leader in the use, development, deployment, and tracking of Solar Industrial Process Heat (SIPH) plants. The objective of this study is to ascertain U.S. market potential of IPH for concentrating collector technologies that have been developed and promoted through the U.S. Department of Energy's Concentrating Solar Power (CSP) Program. For this study, the solar-thermal collector technologies of interest are parabolic trough collectors (PTCs) and linear Fresnel (LF) systems.

  17. Estrogen potentiates reactive oxygen species (ROS) tolerance to initiate carcinogenesis and promote cancer malignant transformation.

    PubMed

    Tian, Hui; Gao, Zhen; Wang, Gang; Li, Huizhong; Zheng, JunNian

    2016-01-01

    Estrogen-mediated high reactive oxygen species (ROS) tolerance plays an important role in driving carcinogenesis. ROS overproduction acts as the significant effector to increase genomic instability and transduce redox-related signal pathway. Especially, estrogen-mediated mitochondrial ROS promote the mutations in mitochondrial DNA (mtDNA) and the damage to mitochondrial proteins. Moreover, estrogen-mediated ROS contribute to the alteration of energy metabolism and modulate several redox-sensitive proteins responsible for cell proliferation and anti-apoptosis. On the other hand, estrogen simultaneously performs the antioxidative beneficial functions, which protects cancer cells from the potential cytotoxic effects of estrogen-mediated ROS through activation of nuclear factor-erythroid-2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1) antioxidant response. Consequently, estrogen potentiates the high ROS tolerance through increase of ROS production as well as acceleration of ROS elimination, which ultimately results in estrogen-mediated carcinogenesis and malignant transformation. However, this overdependence on antioxidant response system to resist ROS-mediated cytotoxicity also represents the "Achilles' Heel" of estrogen-mediated cancer cells. In other words, the destruction of the high ROS tolerance using antioxidant inhibitors may provide a novel and efficacious measure to selectively eliminate these cancer cells without harming normal cells. Of course, it will be necessary to define the exact situation of ROS homeostasis in the different cellular microenvironment and further decipher the mechanisms of redox regulation, which is consequently used as a new avenue to optimize the clinical therapy for estrogen-mediated cancer.

  18. The Initial Boundary Value Problem for the Boltzmann Equation with Soft Potential

    NASA Astrophysics Data System (ADS)

    Liu, Shuangqian; Yang, Xiongfeng

    2017-01-01

    Boundary effects are central to the dynamics of the dilute particles governed by the Boltzmann equation. In this paper, we study both the diffuse reflection and the specular reflection boundary value problems for the Boltzmann equation with a soft potential, in which the collision kernel is ruled by the inverse power law. For the diffuse reflection boundary condition, based on an L 2 argument and its interplay with intricate {L^∞} analysis for the linearized Boltzmann equation, we first establish the global existence and then obtain the exponential decay in {L^∞} space for the nonlinear Boltzmann equation in general classes of bounded domain. It turns out that the zero lower bound of the collision frequency and the singularity of the collision kernel lead to some new difficulties for achieving the a priori {L^∞} estimates and time decay rates of the solution. In the course of the proof, we capture some new properties of the probability integrals along the stochastic cycles and improve the {L^2-L^∞} theory to give a more direct approach to overcome those difficulties. As to the specular reflection condition, our key contribution is to develop a new time-velocity weighted {L^∞} theory so that we could deal with the greater difficulties stemming from the complicated velocity relations among the specular cycles and the zero lower bound of the collision frequency. From this new point, we are also able to prove that the solutions of the linearized Boltzmann equation tend to equilibrium exponentially in {L^∞} space with the aid of the L 2 theory and a bootstrap argument. These methods, in the latter case, can be applied to the Boltzmann equation with soft potential for all other types of boundary condition.

  19. Initial reactions to the Woman's Condom by potential user groups in Shanghai, China.

    PubMed

    Coffey, Patricia S; Kilbourne-Brook, Maggie; Junqing, Wu; Yufeng, Zhang; Hongxin, Zhao; Bin, Wen; Na, Li; Rui, Zhao; Yuyan, Li

    2013-04-01

    The Woman's Condom, a second-generation female condom, is currently being manufactured in China by the Shanghai Dahua Medical Apparatus Company. The manufacturer plans to launch the product in China. A survey and focus group discussions were conducted with 73 women and 57 men from nine potential user groups in the Shanghai area to explore, on the basis of visual inspection of the Woman's Condom and product information, their perceptions and attitudes toward the Woman's Condom and lubricant. The potential user groups were male and female university students, male and female college-educated young people, married women and men, migrant women and men, and women working in the entertainment industry. Female condoms were a new concept for almost all study participants. Women (49%) and men (51%) reported that the Woman's Condom would make "some" or a "great" difference in their lives. Participants reported interest in using the Woman's Condom for sexually transmitted infection (STI) (50%) or dual protection (43%) rather than for pregnancy prevention alone (33%). Findings highlighted comfort, partner approval and lubricant as possible concerns. Product introduction activities should be oriented toward the most likely early adopter groups (i.e. university students, college-educated young people, migrant women and women working in the entertainment industry). Lack of interest in using the new device by married women/men and migrant men may indicate that they do not perceive a need for a dual protection product since they are already using a contraceptive method and/or do not perceive themselves at risk of STIs.

  20. Binding specificities and potential roles of isoforms of eukaryotic initiation factor 4E in Leishmania.

    PubMed

    Yoffe, Yael; Zuberek, Joanna; Lerer, Asaf; Lewdorowicz, Magdalena; Stepinski, Janusz; Altmann, Michael; Darzynkiewicz, Edward; Shapira, Michal

    2006-12-01

    The 5' cap structure of trypanosomatid mRNAs, denoted cap 4, is a complex structure that contains unusual modifications on the first four nucleotides. We examined the four eukaryotic initiation factor 4E (eIF4E) homologues found in the Leishmania genome database. These proteins, denoted LeishIF4E-1 to LeishIF4E-4, are located in the cytoplasm. They show only a limited degree of sequence homology with known eIF4E isoforms and among themselves. However, computerized structure prediction suggests that the cap-binding pocket is conserved in each of the homologues, as confirmed by binding assays to m(7)GTP, cap 4, and its intermediates. LeishIF4E-1 and LeishIF4E-4 each bind m(7)GTP and cap 4 comparably well, and only these two proteins could interact with the mammalian eIF4E binding protein 4EBP1, though with different efficiencies. 4EBP1 is a translation repressor that competes with eIF4G for the same residues on eIF4E; thus, LeishIF4E-1 and LeishIF4E-4 are reasonable candidates for serving as translation factors. LeishIF4E-1 is more abundant in amastigotes and also contains a typical 3' untranslated region element that is found in amastigote-specific genes. LeishIF4E-2 bound mainly to cap 4 and comigrated with polysomal fractions on sucrose gradients. Since the consensus eIF4E is usually found in 48S complexes, LeishIF4E-2 could possibly be associated with the stabilization of trypanosomatid polysomes. LeishIF4E-3 bound mainly m(7)GTP, excluding its involvement in the translation of cap 4-protected mRNAs. It comigrates with 80S complexes which are resistant to micrococcal nuclease, but its function is yet unknown. None of the isoforms can functionally complement the Saccharomyces cerevisiae eIF4E, indicating that despite their structural conservation, they are considerably diverged.

  1. Initial Experience in Single-Incision Transumbilical Laparoscopic Liver Resection: Indications, Potential Benefits, and Limitations

    PubMed Central

    Dapri, Giovanni; DiMarco, Livia; Cadière, Guy-Bernard; Donckier, Vincent

    2012-01-01

    Background. Single-incision transumbilical laparoscopic liver resection (SITLLR) has been recently described in limited series. We report our experience in SITLLR and discuss the future of this approach in terms of indications, potential benefits, and limitations, with a special reference to laparoscopic liver resection (LLR). Patients and Methods. Six patients underwent SITLLR. Indications were biliary cysts (3 cases), hydatid cysts (2), and colorectal liver metastasis (1). Procedures consisted in cysts unroofing, left lateral lobectomy, pericystectomy, and wedge resection. SITLLR was performed with 11 mm reusable trocar, 10 or 5 mm 30° scopes, 10 mm ultrasound probe, curved reusable instruments, and straight disposable bipolar shears. Results. Neither conversion to open surgery nor insertion of supplementary trocars was necessary. Median laparoscopic time was 105.5 minutes and median blood loss 275 mL. Median final umbilical scar length was 1.5 cm, and median length of stay was 4 days. No early or late complications occurred. Conclusion. SITLLR remains a challenging procedure. It is feasible in highly selected patients, requiring experience in hepatobiliary and laparoscopic surgery and skills in single-incision laparoscopy. Apart from cosmetic benefit, our experience and literature review did not show significant advantages if compared with multiport LLR, underlying that specific indications remain to be established. PMID:23082044

  2. An initial comparison of pitting resistance of alloys for potential geothermal applications

    SciTech Connect

    Van Rooyen, D.

    1990-05-01

    In order to use the energy available from geothermal sources, brines of a variety of compositions and temperatures have to be handled. Much of the hardware has consisted of metals, such as used in casings, pipes, valves, turbines, heat exchangers and others. When the pH is not very acid, and oxygen is absent, the brines are not very corrosive. However, there are instances where conditions cause accelerated corrosion. The present work was undertaken to examine one particular form of corrosion, pitting, which is encountered fairly often, and causes early failures in many industries because it is so localized. A number of alloys have been examined in the laboratory for their resistance to pitting corrosion in chloride media. The electrochemical procedure of determining pitting potentials was used. It was found that the most meaningful results could be obtained by increasing the aggressiveness of the test solutions as the resistance to localized attack of individual members of the series of alloys increased. The outcome of the experiments was the creation of a ranking of a large number of alloys according to their performance in the laboratory test program. The range of materials tested include carbon steel at the low end, with Hastelloy C-276 and Titanium at the top. 55 figs., 11 tabs.

  3. Perchlorate formation on Mars through surface radiolysis-initiated atmospheric chemistry: A potential mechanism.

    PubMed

    Wilson, Eric H; Atreya, Sushil K; Kaiser, Ralf I; Mahaffy, Paul R

    2016-08-01

    Recent observations of the Martian surface by the Phoenix lander and the Sample Analysis at Mars indicate the presence of perchlorate (ClO4(-)). The abundance and isotopic composition of these perchlorates suggest that the mechanisms responsible for their formation in the Martian environment may be unique in our solar system. With this in mind, we propose a potential mechanism for the production of Martian perchlorate: the radiolysis of the Martian surface by galactic cosmic rays, followed by the sublimation of chlorine oxides into the atmosphere and their subsequent synthesis to form perchloric acid (HClO4) in the atmosphere, and the surface deposition and subsequent mineralization of HClO4 in the regolith to form surface perchlorates. To evaluate the viability of this mechanism, we employ a one-dimensional chemical model, examining chlorine chemistry in the context of Martian atmospheric chemistry. Considering the chlorine oxide, OClO, we find that an OClO flux as low as 3.2 × 10(7) molecules cm(-2) s(-1) sublimated into the atmosphere from the surface could produce sufficient HClO4 to explain the perchlorate concentration on Mars, assuming an accumulation depth of 30 cm and integrated over the Amazonian period. Radiolysis provides an efficient pathway for the oxidation of chlorine, bypassing the efficient Cl/HCl recycling mechanism that characterizes HClO4 formation mechanisms proposed for the Earth but not Mars.

  4. Mathematical modeling of thrombus formation in idealized models of aortic dissection: initial findings and potential applications.

    PubMed

    Menichini, Claudia; Xu, Xiao Yun

    2016-11-01

    Aortic dissection is a major aortic catastrophe with a high morbidity and mortality risk caused by the formation of a tear in the aortic wall. The development of a second blood filled region defined as the "false lumen" causes highly disturbed flow patterns and creates local hemodynamic conditions likely to promote the formation of thrombus in the false lumen. Previous research has shown that patient prognosis is influenced by the level of thrombosis in the false lumen, with false lumen patency and partial thrombosis being associated with late complications and complete thrombosis of the false lumen having beneficial effects on patient outcomes. In this paper, a new hemodynamics-based model is proposed to predict the formation of thrombus in Type B dissection. Shear rates, fluid residence time, and platelet distribution are employed to evaluate the likelihood for thrombosis and to simulate the growth of thrombus and its effects on blood flow over time. The model is applied to different idealized aortic dissections to investigate the effect of geometric features on thrombus formation. Our results are in qualitative agreement with in-vivo observations, and show the potential applicability of such a modeling approach to predict the progression of aortic dissection in anatomically realistic geometries.

  5. Labour market initiatives: potential settings for improving the health of people who are unemployed.

    PubMed

    Harris, Elizabeth; Rose, Vanessa; Ritchie, Jan; Harris, Neil

    2009-12-01

    Unemployment is detrimental to health. The Unemployment and Health Project in South Western Sydney sought to work with labour market programs to improve the health, particularly, mental health, of unemployed people. This paper describes the experiences of the Project. Phase one commenced in 1995 and involved consultation with the majority of Skillshares (labour market programs under the Labor government) in south-western Sydney to identify potential areas of action. Phase two commenced in 1998 and involved the development of a brief cognitive behaviour therapy intervention that was delivered in Job Network Settings (the next generation of labour market programs under the Liberal government). The cognitive behaviour therapy intervention has been successful in improving mental health in five small scale trials but the intervention has proved difficult to scale up and evaluate comprehensively. Generating more general interest in improving the health of unemployed people through the Job Network has also been difficult. This is related to different understanding and valuing of evidence, a highly volatile context, lack of shared core business by the health and employment sectors, and the changing nature of work in Australia. There are theoretical and practical reasons why it is difficult for labour market programs to be a setting for improving the health of unemployed people. However, the reach of labour market programs into the high risk groups warrants more attention by mental health promotion programs.

  6. Perchlorate Formation on Mars Through Surface Radiolysis-Initiated Atmospheric Chemistry: A Potential Mechanism

    NASA Technical Reports Server (NTRS)

    Wilson, Eric H.; Atreya, Sushil K.; Kaiser, Ralf I.; Mahaffy, Paul R.

    2016-01-01

    Recent observations of the Martian surface by the Phoenix lander and the Sample Analysis at Mars indicate the presence of perchlorate (ClO4). The abundance and isotopic composition of these perchlorates suggest that the mechanisms responsible for their formation in the Martian environment may be unique in our solar system. With this in mind, we propose a potential mechanism for the production of Martian perchlorate: the radiolysis of the Martian surface by galactic cosmic rays, followed by the sublimation of chlorine oxides into the atmosphere and their subsequent synthesis to form perchloric acid (HClO4) in the atmosphere, and the surface deposition and subsequent mineralization of HClO4 in the regolith to form surface perchlorates. To evaluate the viability of this mechanism, we employ a one-dimensional chemical model, examining chlorine chemistry in the context of Martian atmospheric chemistry. Considering the chlorine oxide, OClO, we find that an OClO flux as low as 3.2 x 10(exp 7) molecules/sq cm/s sublimated into the atmosphere from the surface could produce sufficient HClO4 to explain the perchlorate concentration on Mars, assuming an accumulation depth of 30 cm and integrated over the Amazonian period. Radiolysis provides an efficient pathway for the oxidation of chlorine, bypassing the efficient Cl/HCl recycling mechanism that characterizes HClO4 formation mechanisms proposed for the Earth but not Mars.

  7. Perchlorate formation on Mars through surface radiolysis-initiated atmospheric chemistry: A potential mechanism

    NASA Astrophysics Data System (ADS)

    Wilson, Eric H.; Atreya, Sushil K.; Kaiser, Ralf I.; Mahaffy, Paul R.

    2016-08-01

    Recent observations of the Martian surface by the Phoenix lander and the Sample Analysis at Mars indicate the presence of perchlorate (ClO4-). The abundance and isotopic composition of these perchlorates suggest that the mechanisms responsible for their formation in the Martian environment may be unique in our solar system. With this in mind, we propose a potential mechanism for the production of Martian perchlorate: the radiolysis of the Martian surface by galactic cosmic rays, followed by the sublimation of chlorine oxides into the atmosphere and their subsequent synthesis to form perchloric acid (HClO4) in the atmosphere, and the surface deposition and subsequent mineralization of HClO4 in the regolith to form surface perchlorates. To evaluate the viability of this mechanism, we employ a one-dimensional chemical model, examining chlorine chemistry in the context of Martian atmospheric chemistry. Considering the chlorine oxide, OClO, we find that an OClO flux as low as 3.2 × 107 molecules cm-2 s-1 sublimated into the atmosphere from the surface could produce sufficient HClO4 to explain the perchlorate concentration on Mars, assuming an accumulation depth of 30 cm and integrated over the Amazonian period. Radiolysis provides an efficient pathway for the oxidation of chlorine, bypassing the efficient Cl/HCl recycling mechanism that characterizes HClO4 formation mechanisms proposed for the Earth but not Mars.

  8. Remineralization potential of nano-hydroxyapatite on initial enamel lesions: an in vitro study.

    PubMed

    Huang, S; Gao, S; Cheng, L; Yu, H

    2011-01-01

    The application of nano-hydroxyapatite (HA) in the repair of early caries lesion has received considerable attention. Neither the effects of the size of HA nor the effects of the effective pH range of nano-HA on remineralization have been investigated comprehensively, and the protective mechanism is still open for debate. To address these factors, the remineralization effect of nano-HA on demineralized bovine enamel is investigated under pH cycling conditions through surface and cross-sectional microhardness (CSMH) tests and polarized light microscopy (PLM). The percentage of surface microhardness recovery and integrated mineral loss obtained from CSMH tests demonstrated that nano-HA provides better remineralization than micro-HA. However, detailed investigation using CSMH tests and PLM indicated that nano-HA helped mineral deposition predominantly in the outer layer of the lesion and only had a limited capacity to reduce lesion depth. Nevertheless, the remineralization effect of nano-HA increased significantly when the pH was less than 7.0. Clearly, nano-HA has potential as an effective repair material and anticaries agent. Our findings also suggest that both the particle- and ion-mediated remineralization pathways in nano-HA may contribute to the repair of demineralized enamel.

  9. Support of Unrelated Stem Cell Donor Searches by Donor Center-Initiated HLA Typing of Potentially Matching Donors

    PubMed Central

    Schmidt, Alexander H.; Solloch, Ute V.; Baier, Daniel; Grathwohl, Alois; Hofmann, Jan; Pingel, Julia; Stahr, Andrea; Ehninger, Gerhard

    2011-01-01

    Large registries of potential unrelated stem cell donors have been established in order to enable stem cell transplantation for patients without HLA-identical related donors. Donor search is complicated by the fact that the stored HLA information of many registered donors is incomplete. We carried out a project that was aimed to improve chances of patients with ongoing donor searches to find an HLA-matched unrelated donor. For that purpose, we carried out additional donor center-initiated HLA-DRB1 typing of donors who were only typed for the HLA loci A and B so far and were potential matches for patients in need of a stem cell transplant. In total, 8,861 donors were contacted for donor center-initiated HLA-DRB1 typing within 1,089 donor searches. 12 of these donors have donated stem cells so far, 8 thereof for their respective target patients. We conclude that chances of patients with ongoing donor searches to find an HLA-matched unrelated donor can indeed be improved by donor-center initiated typing that is carried out in addition to the standard donor search process. Our results also raise questions regarding the appropriate use of incompletely typed donors within unrelated donor searches. PMID:21625451

  10. Short communication: Initial evidence supporting existence of potential rumen epidermal stem and progenitor cells.

    PubMed

    Yohe, T T; Tucker, H L M; Parsons, C L M; Geiger, A J; Akers, R M; Daniels, K M

    2016-09-01

    The bovine rumen epidermis is a keratinized multilayered tissue that experiences persistent cell turnover. Because of this constant cell turnover, epidermal stem cells and their slightly more differentiated daughter cells, epidermal progenitor cells, must exist in the stratum basale of rumen epidermis. To date, these 2 epidermal cell populations and any unique cellular markers they may possess remain completely uncharacterized in the bovine rumen. An important first step in this new research area is the demonstration of the relative abundance and existence of markers for these cells in rumen tissue. A related second step is to document rumen epidermal proliferative responses to an extrinsic signal such as nutrient concentration within the rumen. The objectives of this experiment were to evaluate the extrinsic effect of diet on (1) gene expression of 6 potential rumen epidermal stem or progenitor cell markers and (2) rumen epidermal cell proliferation within the stratum basale. Twelve preweaned Holstein heifers were fed either a restricted diet (R) or an enhanced diet (EH). Animals on R received a milk replacer (MR) diet fed at 0.44kg of powder dry matter (DM)/d (20.9% crude protein, 29.8% fat, DM basis) and EH received MR at 1.08kg of powder dry matter/d (28.9% crude protein, 26.2% fat, DM basis). All calves had access to a 20% crude protein starter and were weaned during wk 7 of the experiment. Lifetime DM intake was 0.73kg of DM/calf per day for R (5.88 Mcal of net energy/calf per day) and 1.26kg of DM/calf per day for EH (10.68 Mcal of net energy/calf per day). Twenty-four hours before slaughter heifers received an intravenous dose of 5-bromo-2'-deoxyuridine to label proliferating cells. Heifers were slaughtered at 8 wk of age, and rumen samples from the ventral sac region were obtained and stored in RNA preservative and processed for routine histology. Quantitative real-time reverse transcriptase PCR was used to analyze relative abundance of genes. Candidate

  11. AN INITIAL ASSESSMENT OF POTENTIAL PRODUCTION TECHNOLOGIES FOR EPSILON-METAL WASTE FORMS

    SciTech Connect

    Rohatgi, Aashish; Strachan, Denis M.

    2011-03-01

    This report examines and ranks a total of seven materials processing techniques that may be potentially utilized to consolidate the undissolved solids from nuclear fuel reprocessing into a low-surface area form. Commercial vendors of processing equipment were contacted and literature researched to gather information for this report. Typical equipment and their operation, corresponding to each of the seven techniques, are described in the report based upon the discussions and information provided by the vendors. Although the report does not purport to describe all the capabilities and issues of various consolidation techniques, it is anticipated that this report will serve as a guide by highlighting the key advantages and disadvantages of these techniques. The processing techniques described in this report were broadly classified into those that employed melting and solidification, and those in which the consolidation takes place in the solid-state. Four additional techniques were examined that were deemed impractical, but were included for completeness. The techniques were ranked based on criteria such as flexibility in accepting wide-variety of feed-stock (chemistry, form, and quantity), ease of long-term maintenance, hot cell space requirements, generation of additional waste streams, cost, and any special considerations. Based on the assumption of ~2.5 L of waste to be consolidated per day, sintering based techniques, namely, microwave sintering, spark plasma sintering and hot isostatic pressing, were ranked as the top-3 choices, respectively. Melting and solidification based techniques were ranked lower on account of generation of volatile phases and difficulties associated with reactivity and containment of the molten metal.

  12. Characterization of fatigue crack initiation and propagation in Ti-6Al-4V with electrical potential drop technique

    NASA Technical Reports Server (NTRS)

    Kalluri, Sreeramesh; Telesman, Jack

    1988-01-01

    Electrical potential methods have been used in the past primarily to monitor crack length in long crack specimens subjected to fatigue loading. An attempt was made to develop test procedures for monitoring the fatigue crack initiation and the growth of short fatigue cracks in a turbine disk alloy with the electrical potential drop technique (EPDT). In addition, the EPDT was also applied to monitor the fatigue crack growth in long crack specimens of the same alloy. The resolution of the EPDT for different specimen geometries was determined. Factors influencing the EPDT are identified and the applicability of EPDT in implementing damage tolerant design concepts for turbine disk materials is discussed. The experimental procedure adopted and the results obtained is discussed. No substantial differences were observed between the fatigue crack growth data of short and long crack specimens.

  13. Effect of potential waste constituents on the reactivity of Hanford ferrocyanide wastes: Diluent, catalyst, and initiator studies

    SciTech Connect

    Scheele, R.D.; Johnston, J.W.; Tingey, J.M.; Burger, L.L.; Sell, R.L.

    1993-04-01

    During the 1980s, scientists at the Hanford Site began considering disposal options for wastes in underground storage tanks. As a result of safety concerns, it was determined that special consideration should be given to ferrocyanide-bearing wastes to ensure their continued safe storage. In addition, Westinghouse Hanford Company (WHC) chartered Pacific Northwest Laboratory (PNL) to determine the conditions necessary for vigorous reactions to occur in the Hanford Site ferrocyanide wastes. As part of those studies, PNL has evaluated the effects of selected potential waste constituents to determine how they might affect the reactivity of the wastes. The authors` investigations of the diluent, catalytic, or initiating effects of potential waste constituents included studies (1) to determine the effect of the oxidant-to-ferrocyanide ratio, (2) to establish the effect of sodium aluminate concentration, (3) to identify materials that could affect the explosivity of a mixture of sodium nickel ferricyanide (a potential aging product of ferrocyanide) and sodium nitrate and nitrite, (4) and to determine the effect of nickel sulfide concentration. They also conducted a thermal sensitivity study and analyzed the results to determine the relative behaviors of sodium nickel ferrocyanide and ferricyanide. A statistical evaluation of the time-to-explosion (TTX) test results from the catalyst and initiator screening study found that the ferricyanide reacted at a faster rate than did the ferrocyanide analog. The thermal analyses indicated that the ferricyanide form is more thermally sensitive, exhibiting exothermic behavior at a lower temperature than the ferrocyanide form. The increased thermal sensitivity of the ferricyanide, which is a potential oxidation product of ferrocyanide, relative to the ferrocyanide analog, does not support the hypothesis that aging independent of the reaction pathway will necessarily reduce the reaction hazard of ferrocyanide wastes.

  14. Endocytotic elimination and domain-selective tethering constitute a potential mechanism of protein segregation at the axonal initial segment

    PubMed Central

    Fache, Marie-Pierre; Moussif, Anissa; Fernandes, Fanny; Giraud, Pierre; Garrido, Juan José; Dargent, Bénédicte

    2004-01-01

    The axonal initial segment is a unique subdomain of the neuron that maintains cellular polarization and contributes to electrogenesis. To obtain new insights into the mechanisms that determine protein segregation in this subdomain, we analyzed the trafficking of a reporter protein containing the cytoplasmic II–III linker sequence involved in sodium channel targeting and clustering (Garrido, J.J., P. Giraud, E. Carlier, F. Fernandes, A. Moussif, M.P. Fache, D. Debanne, and B. Dargent. 2003. Science. 300:2091–2094). Here, we show that this reporter protein is preferentially inserted in the somatodendritic domain and is trapped at the axonal initial segment by tethering to the cytoskeleton, before its insertion in the axonal tips. The nontethered population in dendrites, soma, and the distal part of axons is subsequently eliminated by endocytosis. We provide evidence for the involvement of two independent determinants in the II–III linker of sodium channels. These findings indicate that endocytotic elimination and domain-selective tethering constitute a potential mechanism of protein segregation at the axonal initial segment of hippocampal neurons. PMID:15302857

  15. Action potential initiation in a two-compartment model of pyramidal neuron mediated by dendritic Ca(2+) spike.

    PubMed

    Yi, Guosheng; Wang, Jiang; Wei, Xile; Deng, Bin

    2017-04-03

    Dendritic Ca(2+) spike endows cortical pyramidal cell with powerful ability of synaptic integration, which is critical for neuronal computation. Here we propose a two-compartment conductance-based model to investigate how the Ca(2+) activity of apical dendrite participates in the action potential (AP) initiation to affect the firing properties of pyramidal neurons. We have shown that the apical input with sufficient intensity triggers a dendritic Ca(2+) spike, which significantly boosts dendritic inputs as it propagates to soma. Such event instantaneously shifts the limit cycle attractor of the neuron and results in a burst of APs, which makes its firing rate reach a plateau steady-state level. Delivering current to two chambers simultaneously increases the level of neuronal excitability and decreases the threshold of input-output relation. Here the back-propagating APs facilitate the initiation of dendritic Ca(2+) spike and evoke BAC firing. These findings indicate that the proposed model is capable of reproducing in vitro experimental observations. By determining spike initiating dynamics, we have provided a fundamental link between dendritic Ca(2+) spike and output APs, which could contribute to mechanically interpreting how dendritic Ca(2+) activity participates in the simple computations of pyramidal neuron.

  16. The potential role of COX-2 in cancer stem cell-mediated canine mammary tumor initiation: an immunohistochemical study.

    PubMed

    Huang, Jian; Zhang, Di; Xie, Fuqiang; Lin, Degui

    2015-01-01

    Increasing evidence suggests that cancer stem cells (CSCs) are responsible for tumor initiation and maintenance. Additionally, it is becoming apparent that cyclooxygenase (COX) signaling is associated with canine mammary tumor development. The goals of the present study were to investigate COX-2 expression patterns and their effect on CSC-mediated tumor initiation in primary canine mammary tissues and tumorsphere models using immunohistochemistry. Patterns of COX-2, CD44, octamer-binding transcription factor (Oct)-3/4, and epidermal growth factor receptor (EGFR) expression were examined in malignant mammary tumor (MMT) samples and analyzed in terms of clinicopathological characteristics. COX-2 and Oct-3/4 expression was higher in MMTs compared to other histological samples with heterogeneous patterns. In MMTs, COX-2 expression correlated with tumor malignancy features. Significant associations between COX-2, CD44, and EGFR were observed in low-differentiated MMTs. Comparative analysis showed that the levels of COX-2, CD44, and Oct-3/4 expression varied significantly among TSs of three histological grades. Enhanced COX-2 staining was consistently observed in TSs. Similar levels of staining intensity were found for CD44 and Oct-3/4, but EGFR expression was weak. Our findings indicate the potential role of COX-2 in CSC-mediated tumor initiation, and suggest that COX-2 inhibition may help treat canine mammary tumors by targeting CSCs.

  17. Action potential initiation in a two-compartment model of pyramidal neuron mediated by dendritic Ca2+ spike

    PubMed Central

    Yi, Guosheng; Wang, Jiang; Wei, Xile; Deng, Bin

    2017-01-01

    Dendritic Ca2+ spike endows cortical pyramidal cell with powerful ability of synaptic integration, which is critical for neuronal computation. Here we propose a two-compartment conductance-based model to investigate how the Ca2+ activity of apical dendrite participates in the action potential (AP) initiation to affect the firing properties of pyramidal neurons. We have shown that the apical input with sufficient intensity triggers a dendritic Ca2+ spike, which significantly boosts dendritic inputs as it propagates to soma. Such event instantaneously shifts the limit cycle attractor of the neuron and results in a burst of APs, which makes its firing rate reach a plateau steady-state level. Delivering current to two chambers simultaneously increases the level of neuronal excitability and decreases the threshold of input-output relation. Here the back-propagating APs facilitate the initiation of dendritic Ca2+ spike and evoke BAC firing. These findings indicate that the proposed model is capable of reproducing in vitro experimental observations. By determining spike initiating dynamics, we have provided a fundamental link between dendritic Ca2+ spike and output APs, which could contribute to mechanically interpreting how dendritic Ca2+ activity participates in the simple computations of pyramidal neuron. PMID:28367964

  18. Stabilization of the initial electrochemical potential for a metal-based potentiometric titration study of a biosorption process.

    PubMed

    Naja, Ghinwa; Mustin, Christian; Volesky, Bohumil; Berthelin, Jacques

    2006-01-01

    An interactive metal-based potentiometric titration method has been developed using an ion selective electrode for studying the sorption of metal cations. The accuracy of this technique was verified by analyzing the metal sorption mechanism for the biomass of Rhizopus arrhizus fungus and diatomite, two dissimilar materials (organic and mineral, strong sorbent and weak sorbent) of a different order of cation exchange capacity. The problem of the initial electrochemical potential was addressed identifying the usefulness of a Na-sulfonic resin as a strong chelating agent applied before the beginning of sorption titration experiments so that the titration curves and the sorption uptake could be quantitatively compared. The resin stabilized the initial electrochemical potential to -405+/-5 mV corresponding to 2 micro gl(-1) of lead concentration in solution. The amounts of lead sorbed by R. arrhizus biomass and diatomite were 0.9 mmol g(-1) (C(e)=5.16 x 10(-2)mM) and 0.052 mmol g(-1) (C(e)=5.97 x 10(-2) mM), respectively. Lead sorption by the fungal biomass was pinpointed to at least two types of chemical active sites. The first type was distinguished by high reactivity and a low number of sites whereas the other was characterized by their higher number and lower reactivity.

  19. The Potential Association of Later Initiation of Oral/Enteral Nutrition on Euthyroid Sick Syndrome in Burn Patients

    PubMed Central

    Pérez-Guisado, Joaquín; de Haro-Padilla, Jesús M.; Rioja, Luis F.; DeRosier, Leo C.; de la Torre, Jorge I.

    2013-01-01

    Objective. The aim of this study was to determine if early initiation of oral/enteral nutrition in burn patients minimizes the drop in fT3 levels, reduces the potential for euthyroid sick syndrome (ESS), and shortens the length of hospital stay (LHS). Subjects and Methods. We retrospectively evaluated the statistical association of serum fT3, fT4, and TSH at the first (2nd–5th day) and second sample collection (9th–12th day) after the burn injury in 152 burn patients. Three groups were established depending on time of initiation of the oral/enteral nutrition: <24 h before the injury (Group 1), 24–48 h after the injury (Group 2), and >48 h after the injury (Group 3). Results. They were expressed as mean ± standard deviation. We found that LHS and the fT3 levels were statistically different in the 3 groups. The LHS (in days) was, respectively, in each group, 16.77 ± 4.56, 21.98 ± 4.86, and 26.06 ± 5.47. Despite the quantifiable drop in fT3, ESS was present only at the first sample collection (2.61 ± 0.92 days) in Group 3, but there was no group with ESS at the second sample collection (9.89 ± 1.01 days). Our data suggest that early initiation of nutritional supplementation decreases the length of hospitalization and is associated with decreasing fT3 serum concentration depression. Conclusion. Early initiation of oral/enteral nutrition counteracts ESS and improves the LHS in burn patients. PMID:23401683

  20. Health Care Reform and the Federal Transformation Initiatives: Capitalizing on the Potential of Advanced Practice Psychiatric Nurses

    PubMed Central

    Hanrahan, Nancy P.; Delaney, Kathleen; Merwin, Elizabeth

    2012-01-01

    In the last decade the US federal government proposed a transformation vision of mental health service delivery; patient-centered, evidence-based and recovery oriented treatment models. Health care reform brings additional expectations for innovation in mental/substance use service delivery, particularly the idea of creating systems where physical health, mental health and substance use treatment is fully integrated. Psychiatric nurses, as one of the four core US mental health professions, have the potential to play a significant role in the both the transformation initiative and health care reform vision. However, psychiatric nurses, particularly advanced practice psychiatric nurses, are an untapped resource due in part to significant state regulatory barriers that limit their scope of practice in many states. The purpose of this paper is to document what is currently known about advanced practice psychiatric nurses and discuss policy implications for tapping into the strengths of this workforce. Strategies for facilitating utilization of advanced practice psychiatric nurses discussed. PMID:21233135

  1. Carbon storage and potential methane production in the Hudson Bay Lowlands since mid-Holocene peat initiation.

    PubMed

    Packalen, Maara S; Finkelstein, Sarah A; McLaughlin, James W

    2014-06-11

    Peatlands have influenced Holocene carbon (C) cycling by storing atmospheric C and releasing methane (CH4). Yet, our understanding of contributions from the world's second largest peatland, the Hudson Bay Lowlands (HBL), Canada, to peat-climate-C-dynamics is constrained by the paucity of dated peat records and regional C-data. Here we examine HBL peatland development in relation to Holocene C-dynamics. We show that peat initiation in the HBL is tightly coupled with glacial isostatic adjustment (GIA) through most of the record, and occurred within suitable climatic conditions for peatland development. HBL peatlands initiated most intensively in the mid-Holocene, when GIA was most rapid and climate was cooler and drier. As the peat mass developed, we estimate that the HBL potentially released 1-7 Tg CH4 per year during the late Holocene. Our results indicate that the HBL currently stores a C-pool of ~30 Pg C and provide support for a peatland-derived CH4 contribution to the late Holocene atmosphere.

  2. The potential spread of severe footrot in Norway if no elimination programme had been initiated: a simulation model.

    PubMed

    Grøneng, Gry M; Vatn, Synnøve; Kristoffersen, Anja Bråthen; Nafstad, Ola; Hopp, Petter

    2015-02-20

    When severe footrot was detected in Norway in 2008, a surveillance programme was initiated and followed by an elimination programme. By 2013 the disease had spread to two of 19 counties and a total of 119 (1%) sheep flocks had been diagnosed with severe footrot. A simulation model was developed to estimate the potential spread of severe footrot in Norway and to estimate the relative importance of the different spreading routes. The model parameters were based on the rate of spread of the first 38 diagnosed cases and the management and climatic factors particular for Norway. The model showed that by 2013, severe footrot would have spread to six counties and infected 16% of the sheep flocks if no elimination programme had been initiated. If this is compared with the 1% of flocks that were diagnosed in Norway by 2013, there seems to be a large effect of the implemented footrot elimination programme. By 2035, it was estimated that severe footrot would have spread to 16 counties and 64% of the sheep flocks. Such an extensive spread would probably impose a large negative impact on the sheep industry and welfare of the sheep. The most effective way to curb the spread of severe footrot was by decreasing the within county infection rate. This could be achieved by decreasing the contact between flocks or by decreasing the environmental load of D. nodosus, for example by footbathing sheep, culling diseased sheep or eliminating severe footrot in the flock.

  3. The initiator methionine tRNA drives cell migration and invasion leading to increased metastatic potential in melanoma

    PubMed Central

    Birch, Joanna; Clarke, Cassie J.; Campbell, Andrew D.; Campbell, Kirsteen; Mitchell, Louise; Liko, Dritan; Kalna, Gabriela; Strathdee, Douglas; Sansom, Owen J.; Neilson, Matthew; Blyth, Karen

    2016-01-01

    ABSTRACT The cell's repertoire of transfer RNAs (tRNAs) has been linked to cancer. Recently, the level of the initiator methionine tRNA (tRNAiMet) in stromal fibroblasts has been shown to influence extracellular matrix (ECM) secretion to drive tumour growth and angiogenesis. Here we show that increased tRNAiMet within cancer cells does not influence tumour growth, but drives cell migration and invasion via a mechanism that is independent from ECM synthesis and dependent on α5β1 integrin and levels of the translation initiation ternary complex. In vivo and ex vivo migration (but not proliferation) of melanoblasts is significantly enhanced in transgenic mice which express additional copies of the tRNAiMet gene. We show that increased tRNAiMet in melanoma drives migratory, invasive behaviour and metastatic potential without affecting cell proliferation and primary tumour growth, and that expression of RNA polymerase III-associated genes (which drive tRNA expression) are elevated in metastases by comparison with primary tumours. Thus, specific alterations to the cancer cell tRNA repertoire drive a migration/invasion programme that may lead to metastasis. PMID:27543055

  4. Phasic excitation of ventral tegmental dopamine neurons potentiates the initiation of conditioned approach behavior: parametric and reinforcement-schedule analyses.

    PubMed

    Ilango, Anton; Kesner, Andrew J; Broker, Carl J; Wang, Dong V; Ikemoto, Satoshi

    2014-01-01

    Midbrain dopamine neurons are implicated in motivation and learning. However, it is unclear how phasic excitation of dopamine neurons, which is implicated in learning, is involved in motivation. Here we used a self-stimulation procedure to examine how mice seek for optogenetically-induced phasic excitation of dopamine neurons, with an emphasis on the temporal dimension. TH-Cre transgenic mice received adeno-associated viral vectors encoding channelrhodopsin-2 into the ventral tegmental area, resulting in selective expression of the opsin in dopamine neurons. These mice were trained to press on a lever for photo-pulse trains that phasically excited dopamine neurons. They learned to self-stimulate in a fast, constant manner, and rapidly reduced pressing during extinction. We first determined effective parameters of photo-pulse trains in self-stimulation. Lever-press rates changed as a function of the manipulation of pulse number, duration, intensity, and frequency. We then examined effects of interval and ratio schedules of reinforcement on photo-pulse train reinforcement, which was contrasted with food reinforcement. Reinforcement with food inhibited lever pressing for a few seconds, after which pressing was robustly regulated in a goal-directed manner. In contrast, phasic excitation of dopamine neurons robustly potentiated the initiation of lever pressing; however, this effect did not last more than 1 s and quickly diminished. Indeed, response rates markedly decreased when lever pressing was reinforced with inter-reinforcement interval schedules of 3 or 10 s or ratio schedules requiring multiple responses per reinforcement. Thus, phasic excitation of dopamine neurons briefly potentiates the initiation of approach behavior with apparent lack of long-term motivational regulation.

  5. Different Rho GTPase–dependent signaling pathways initiate sequential steps in the consolidation of long-term potentiation

    PubMed Central

    Chen, Lulu Y.; Sharma, Anupam; Liu, Jihua; Babayan, Alex H.; Gall, Christine M.; Lynch, Gary

    2009-01-01

    The releasable factor adenosine blocks the formation of long-term potentiation (LTP). These experiments used this observation to uncover the synaptic processes that stabilize the potentiation effect. Brief adenosine infusion blocked stimulation-induced actin polymerization within dendritic spines along with LTP itself in control rat hippocampal slices but not in those pretreated with the actin filament stabilizer jasplakinolide. Adenosine also blocked activity-driven phosphorylation of synaptic cofilin but not of synaptic p21-activated kinase (PAK). A search for the upstream origins of these effects showed that adenosine suppressed RhoA activity but only modestly affected Rac and Cdc42. A RhoA kinase (ROCK) inhibitor reproduced adenosine's effects on cofilin phosphorylation, spine actin polymerization, and LTP, whereas a Rac inhibitor did not. However, inhibitors of Rac or PAK did prolong LTP's vulnerability to reversal by latrunculin, a toxin which blocks actin filament assembly. Thus, LTP induction initiates two synaptic signaling cascades: one (RhoA-ROCK-cofilin) leads to actin polymerization, whereas the other (Rac-PAK) stabilizes the newly formed filaments. PMID:19596849

  6. Potential Impacts of Leakage from Black Rock Reservoir on the Hanford Site Unconfined Aquifer: Initial Hypothetical Simulations of Flow and Contaminant Transport - Errata

    SciTech Connect

    Freedman, Vicky L.

    2007-04-30

    Errata for report documenting initial scoping calculations investigating the potential impacts on the Hanford unconfined aquifer resulting from leakage from the proposed Black Rock Reservoir to the west. These calculations were performed for the U.S. Bureau of Reclamation.

  7. The potential impact of enhanced accident tolerant cladding materials on reactivity initiated accidents in light water reactors

    SciTech Connect

    Brown, Nicholas R.; Wysocki, Aaron J.; Terrani, Kurt A.; Xu, Kevin G.; Wachs, Daniel M.

    2017-01-01

    Here, advanced cladding materials with potentially enhanced accident tolerance will yield different light-water-reactor performance and safety characteristics than the present zirconium-based cladding alloys. These differences are due to cladding material properties, reactor physics, thermal, and hydraulic characteristics. Differences in reactors physics characteristics are driven by the fundamental properties (e.g., absorption in iron for an iron-based cladding) and also by design modifications necessitated by the candidate cladding materials (e.g., a larger fuel pellet to compensate for parasitic absorption). Potential changes in thermal hydraulic limits after transition from the current zirconium alloy cladding to the advanced materials will also affect the transient response of the integral fuel. This paper describes three-dimensional nodal kinetics simulations of a reactivity-initiated accident (RIA) in a representative state-of-the-art pressurized water reactor with both nuclear-grade iron-chromium-aluminum (FeCrAl) and silicon-carbide (SiC-SiC)-based cladding materials. The impact of candidate cladding materials on the reactor kinetics behavior of RIA progression versus that of reference Zr cladding is predominantly due to differences in (1) fuel mass/volume/specific power density, (2) spectral effects due to parasitic neutron absorption, (3) control rod worth due to hardened (or softened) spectrum, and (4) initial conditions due to power peaking and neutron transport cross sections in the equilibrium cycle cores resulting from hardened (or softened) spectrum. This study shows similar behavior for SiC-SiC-based cladding configurations on the transient response versus reference Zircaloy cladding. However, the FeCrAl cladding response indicates similar energy deposition, but with significantly shorter pulses of higher magnitude. This is due to the shorter neutron generation time of the models with FeCrAl cladding. Therefore, the FeCrAl-based cases have a more

  8. The potential impact of enhanced accident tolerant cladding materials on reactivity initiated accidents in light water reactors

    DOE PAGES

    Brown, Nicholas R.; Wysocki, Aaron J.; Terrani, Kurt A.; ...

    2017-01-01

    Here, advanced cladding materials with potentially enhanced accident tolerance will yield different light-water-reactor performance and safety characteristics than the present zirconium-based cladding alloys. These differences are due to cladding material properties, reactor physics, thermal, and hydraulic characteristics. Differences in reactors physics characteristics are driven by the fundamental properties (e.g., absorption in iron for an iron-based cladding) and also by design modifications necessitated by the candidate cladding materials (e.g., a larger fuel pellet to compensate for parasitic absorption). Potential changes in thermal hydraulic limits after transition from the current zirconium alloy cladding to the advanced materials will also affect the transientmore » response of the integral fuel. This paper describes three-dimensional nodal kinetics simulations of a reactivity-initiated accident (RIA) in a representative state-of-the-art pressurized water reactor with both nuclear-grade iron-chromium-aluminum (FeCrAl) and silicon-carbide (SiC-SiC)-based cladding materials. The impact of candidate cladding materials on the reactor kinetics behavior of RIA progression versus that of reference Zr cladding is predominantly due to differences in (1) fuel mass/volume/specific power density, (2) spectral effects due to parasitic neutron absorption, (3) control rod worth due to hardened (or softened) spectrum, and (4) initial conditions due to power peaking and neutron transport cross sections in the equilibrium cycle cores resulting from hardened (or softened) spectrum. This study shows similar behavior for SiC-SiC-based cladding configurations on the transient response versus reference Zircaloy cladding. However, the FeCrAl cladding response indicates similar energy deposition, but with significantly shorter pulses of higher magnitude. This is due to the shorter neutron generation time of the models with FeCrAl cladding. Therefore, the FeCrAl-based cases have

  9. S100A1 promotes action potential-initiated calcium release flux and force production in skeletal muscle.

    PubMed

    Prosser, Benjamin L; Hernández-Ochoa, Erick O; Lovering, Richard M; Andronache, Zoita; Zimmer, Danna B; Melzer, Werner; Schneider, Martin F

    2010-11-01

    The role of S100A1 in skeletal muscle is just beginning to be elucidated. We have previously shown that skeletal muscle fibers from S100A1 knockout (KO) mice exhibit decreased action potential (AP)-evoked Ca(2+) transients, and that S100A1 binds competitively with calmodulin to a canonical S100 binding sequence within the calmodulin-binding domain of the skeletal muscle ryanodine receptor. Using voltage clamped fibers, we found that Ca(2+) release was suppressed at all test membrane potentials in S100A1(-/-) fibers. Here we examine the role of S100A1 during physiological AP-induced muscle activity, using an integrative approach spanning AP propagation to muscle force production. With the voltage-sensitive indicator di-8-aminonaphthylethenylpyridinium, we first demonstrate that the AP waveform is not altered in flexor digitorum brevis muscle fibers isolated from S100A1 KO mice. We then use a model for myoplasmic Ca(2+) binding and transport processes to calculate sarcoplasmic reticulum Ca(2+) release flux initiated by APs and demonstrate decreased release flux and greater inactivation of flux in KO fibers. Using in vivo stimulation of tibialis anterior muscles in anesthetized mice, we show that the maximal isometric force response to twitch and tetanic stimulation is decreased in S100A1(-/-) muscles. KO muscles also fatigue more rapidly upon repetitive stimulation than those of wild-type counterparts. We additionally show that fiber diameter, type, and expression of key excitation-contraction coupling proteins are unchanged in S100A1 KO muscle. We conclude that the absence of S100A1 suppresses physiological AP-induced Ca(2+) release flux, resulting in impaired contractile activation and force production in skeletal muscle.

  10. Effect of the Initial Synaptic State on the Probability to Induce Long-Term Potentiation and Depression

    PubMed Central

    Migliore, Michele; De Simone, Giada; Migliore, Rosanna

    2015-01-01

    Long-term potentiation (LTP) and long-term depression (LTD) are the two major forms of long-lasting synaptic plasticity in the mammalian neurons, and are directly related to higher brain functions such as learning and memory. Experimentally, they are characterized by a change in the strength of a synaptic connection induced by repetitive and properly patterned stimulation protocols. Although many important details of the molecular events leading to LTP and LTD are known, experimenters often report problems in using standard induction protocols to obtain consistent results, especially for LTD in vivo. We hypothesize that a possible source of confusion in interpreting the results, from any given experiment on synaptic plasticity, can be the intrinsic limitation of the experimental techniques, which cannot take into account the actual state and peak conductance of the synapses before the conditioning protocol. In this article, we investigate the possibility that the same experimental protocol may result in different consequences (e.g., LTD instead of LTP), according to the initial conditions of the stimulated synapses, and can generate confusing results. Using biophysical models of synaptic plasticity and hippocampal CA1 pyramidal neurons, we study how, why, and to what extent the phenomena observed at the soma after induction of LTP/LTD reflects the actual (local) synaptic state. The model and the results suggest a physiologically plausible explanation for why LTD induction is experimentally difficult to obtain. They also suggest experimentally testable predictions on the stimulation protocols that may be more effective. PMID:25762316

  11. ERN1 and ALPK1 inhibit differentiation of bi-potential tumor-initiating cells in human breast cancer

    PubMed Central

    Strietz, Juliane; Stepputtis, Stella S.; Vannier, Corinne; Kim, Mihee M.; Castro, David J.; Au, Qingyan; Boerries, Melanie; Busch, Hauke; Aza-Blanc, Pedro; Heynen-Genel, Susanne; Bronsert, Peter; Kuster, Bernhard; Stickeler, Elmar; Brabletz, Thomas; Oshima, Robert G.; Maurer, Jochen

    2016-01-01

    Cancers are heterogeneous by nature. While traditional oncology screens commonly use a single endpoint of cell viability, altering the phenotype of tumor-initiating cells may reveal alternative targets that regulate cellular growth by processes other than apoptosis or cell division. We evaluated the impact of knocking down expression of 420 kinases in bi-lineage triple-negative breast cancer (TNBC) cells that express characteristics of both myoepithelial and luminal cells. Knockdown of ERN1 or ALPK1 induces bi-lineage MDA-MB-468 cells to lose the myoepithelial marker keratin 5 but not the luminal markers keratin 8 and GATA3. In addition, these cells exhibit increased β-casein production. These changes are associated with decreased proliferation and clonogenicity in spheroid cultures and anchorage-independent growth assays. Confirmation of these assays was completed in vivo, where ERN1- or ALPK1-deficient TNBC cells are less tumorigenic. Finally, treatment with K252a, a kinase inhibitor active on ERN1, similarly impairs anchorage-independent growth of multiple breast cancer cell lines. This study supports the strategy to identify new molecular targets for types of cancer driven by cells that retain some capacity for normal differentiation to a non-tumorigenic phenotype. ERN1 and ALPK1 are potential targets for therapeutic development. PMID:27829216

  12. Long-term in vitro maintenance of clonal abundance and leukaemia-initiating potential in acute lymphoblastic leukaemia.

    PubMed

    Pal, D; Blair, H J; Elder, A; Dormon, K; Rennie, K J; Coleman, D J L; Weiland, J; Rankin, K S; Filby, A; Heidenreich, O; Vormoor, J

    2016-08-01

    Lack of suitable in vitro culture conditions for primary acute lymphoblastic leukaemia (ALL) cells severely impairs their experimental accessibility and the testing of new drugs on cell material reflecting clonal heterogeneity in patients. We show that Nestin-positive human mesenchymal stem cells (MSCs) support expansion of a range of biologically and clinically distinct patient-derived ALL samples. Adherent ALL cells showed an increased accumulation in the S phase of the cell cycle and diminished apoptosis when compared with cells in the suspension fraction. Moreover, surface expression of adhesion molecules CD34, CDH2 and CD10 increased several fold. Approximately 20% of the ALL cells were in G0 phase of the cell cycle, suggesting that MSCs may support quiescent ALL cells. Cellular barcoding demonstrated long-term preservation of clonal abundance. Expansion of ALL cells for >3 months compromised neither feeder dependence nor cancer initiating ability as judged by their engraftment potential in immunocompromised mice. Finally, we demonstrate the suitability of this co-culture approach for the investigation of drug combinations with luciferase-expressing primograft ALL cells. Taken together, we have developed a preclinical platform with patient-derived material that will facilitate the development of clinically effective combination therapies for ALL.

  13. PPARG is central to the initiation and propagation of human angiomyolipoma, suggesting its potential as a therapeutic target.

    PubMed

    Pleniceanu, Oren; Shukrun, Racheli; Omer, Dorit; Vax, Einav; Kanter, Itamar; Dziedzic, Klaudyna; Pode-Shakked, Naomi; Mark-Daniei, Michal; Pri-Chen, Sara; Gnatek, Yehudit; Alfandary, Hadas; Varda-Bloom, Nira; Bar-Lev, Dekel D; Bollag, Naomi; Shtainfeld, Rachel; Armon, Leah; Urbach, Achia; Kalisky, Tomer; Nagler, Arnon; Harari-Steinberg, Orit; Arbiser, Jack L; Dekel, Benjamin

    2017-04-01

    Angiomyolipoma (AML), the most common benign renal tumor, can result in severe morbidity from hemorrhage and renal failure. While mTORC1 activation is involved in its growth, mTORC1 inhibitors fail to eradicate AML, highlighting the need for new therapies. Moreover, the identity of the AML cell of origin is obscure. AML research, however, is hampered by the lack of in vivo models. Here, we establish a human AML-xenograft (Xn) model in mice, recapitulating AML at the histological and molecular levels. Microarray analysis demonstrated tumor growth in vivo to involve robust PPARG-pathway activation. Similarly, immunostaining revealed strong PPARG expression in human AML specimens. Accordingly, we demonstrate that while PPARG agonism accelerates AML growth, PPARG antagonism is inhibitory, strongly suppressing AML proliferation and tumor-initiating capacity, via a TGFB-mediated inhibition of PDGFB and CTGF. Finally, we show striking similarity between AML cell lines and mesenchymal stem cells (MSCs) in terms of antigen and gene expression and differentiation potential. Altogether, we establish the first in vivo human AML model, which provides evidence that AML may originate in a PPARG-activated renal MSC lineage that is skewed toward adipocytes and smooth muscle and away from osteoblasts, and uncover PPARG as a regulator of AML growth, which could serve as an attractive therapeutic target.

  14. Design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite as a potential bone graft substitute material

    NASA Astrophysics Data System (ADS)

    Florschutz, Anthony Vatroslav

    Utilization of bone grafts for the treatment of skeletal pathology is a common practice in orthopaedic, craniomaxillofacial, dental, and plastic surgery. Autogenous bone graft is the established archetype but has disadvantages including donor site morbidity, limited supply, and prolonging operative time. In order to avoid these and other issues, bone graft substitute materials are becoming increasingly prevalent among surgeons for reconstructing skeletal defects and arthrodesis applications. Bone graft substitutes are biomaterials, biologics, and guided tissue/bone regenerative devices that can be used alone or in combinations as supplements or alternatives to autogenous bone graft. There is a growing interest and trend to specialize graft substitutes for specific indications and although there is good rationale for this indication-specific approach, the development and utility of a more universal bone graft substitute may provide a better answer for patients and surgeons. The aim of the present research focuses on the design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite composites for potential use as a bone graft substitutes. After initial establishment of rational material design, gelatinhydroxyapatite scaffolds were fabricated with different gelatin:hydroxyapatite ratios and crosslinking concentrations. The synthesized scaffolds were subsequently evaluated on the basis of their swelling behavior, porosity, density, percent composition, mechanical properties, and morphology and further assessed with respect to cell-biomaterial interaction and biomineralization in vitro. Although none of the materials achieved mechanical properties suitable for structural graft applications, a reproducible material design and synthesis was achieved with properties recognized to facilitate bone formation. Select scaffold formulations as well as a subset of scaffolds loaded with recombinant human bone morphogenetic protein-2 were

  15. Non-chemical stressors and cumulative risk assessment: an overview of current initiatives and potential air pollutant interactions.

    PubMed

    Lewis, Ari S; Sax, Sonja N; Wason, Susan C; Campleman, Sharan L

    2011-06-01

    Regulatory agencies are under increased pressure to consider broader public health concerns that extend to multiple pollutant exposures, multiple exposure pathways, and vulnerable populations. Specifically, cumulative risk assessment initiatives have stressed the importance of considering both chemical and non-chemical stressors, such as socioeconomic status (SES) and related psychosocial stress, in evaluating health risks. The integration of non-chemical stressors into a cumulative risk assessment framework has been largely driven by evidence of health disparities across different segments of society that may also bear a disproportionate risk from chemical exposures. This review will discuss current efforts to advance the field of cumulative risk assessment, highlighting some of the major challenges, discussed within the construct of the traditional risk assessment paradigm. Additionally, we present a summary of studies of potential interactions between social stressors and air pollutants on health as an example of current research that supports the incorporation of non-chemical stressors into risk assessment. The results from these studies, while suggestive of possible interactions, are mixed and hindered by inconsistent application of social stress indicators. Overall, while there have been significant advances, further developments across all of the risk assessment stages (i.e., hazard identification, exposure assessment, dose-response, and risk characterization) are necessary to provide a scientific basis for regulatory actions and effective community interventions, particularly when considering non-chemical stressors. A better understanding of the biological underpinnings of social stress on disease and implications for chemical-based dose-response relationships is needed. Furthermore, when considering non-chemical stressors, an appropriate metric, or series of metrics, for risk characterization is also needed. Cumulative risk assessment research will benefit

  16. Non-Chemical Stressors and Cumulative Risk Assessment: An Overview of Current Initiatives and Potential Air Pollutant Interactions

    PubMed Central

    Lewis, Ari S.; Sax, Sonja N.; Wason, Susan C.; Campleman, Sharan L.

    2011-01-01

    Regulatory agencies are under increased pressure to consider broader public health concerns that extend to multiple pollutant exposures, multiple exposure pathways, and vulnerable populations. Specifically, cumulative risk assessment initiatives have stressed the importance of considering both chemical and non-chemical stressors, such as socioeconomic status (SES) and related psychosocial stress, in evaluating health risks. The integration of non-chemical stressors into a cumulative risk assessment framework has been largely driven by evidence of health disparities across different segments of society that may also bear a disproportionate risk from chemical exposures. This review will discuss current efforts to advance the field of cumulative risk assessment, highlighting some of the major challenges, discussed within the construct of the traditional risk assessment paradigm. Additionally, we present a summary of studies of potential interactions between social stressors and air pollutants on health as an example of current research that supports the incorporation of non-chemical stressors into risk assessment. The results from these studies, while suggestive of possible interactions, are mixed and hindered by inconsistent application of social stress indicators. Overall, while there have been significant advances, further developments across all of the risk assessment stages (i.e., hazard identification, exposure assessment, dose-response, and risk characterization) are necessary to provide a scientific basis for regulatory actions and effective community interventions, particularly when considering non-chemical stressors. A better understanding of the biological underpinnings of social stress on disease and implications for chemical-based dose-response relationships is needed. Furthermore, when considering non-chemical stressors, an appropriate metric, or series of metrics, for risk characterization is also needed. Cumulative risk assessment research will benefit

  17. The Challenges of School-Based Teacher Development Initiatives in South Africa and the Potential of Cluster Teaching

    ERIC Educational Resources Information Center

    de Clercq, Francine; Phiri, Rachel

    2013-01-01

    This article examines the challenges of teacher development strategies in post-1994 South Africa by arguing that school-based development initiatives address teachers' specific development needs and that it is imperative to understand the conditions under which these initiatives can have a positive impact on teachers. A framework is developed…

  18. The Challenges of School-Based Teacher Development Initiatives in South Africa and the Potential of Cluster Teaching

    ERIC Educational Resources Information Center

    de Clercq, Francine; Phiri, Rachel

    2013-01-01

    This article examines the challenges of teacher development strategies in post-1994 South Africa by arguing that school-based development initiatives address teachers' specific development needs and that it is imperative to understand the conditions under which these initiatives can have a positive impact on teachers. A framework is developed…

  19. Transition from colitis to cancer: high Wnt activity sustains the tumor-initiating potential of colon cancer stem cell precursors.

    PubMed

    Shenoy, Anitha K; Fisher, Robert C; Butterworth, Elizabeth A; Pi, Liya; Chang, Lung-Ji; Appelman, Henry D; Chang, Myron; Scott, Edward W; Huang, Emina H

    2012-10-01

    Ulcerative colitis (UC) increases the risk of colorectal cancer (CRC), but the mechanisms involved in colitis-to-cancer transition (CCT) are not well understood. CCT may involve a inflammation-dysplasia-carcinoma progression sequence compared with the better characterized adenoma-carcinoma progression sequence associated with sporadic CRC. One common thread may be activating mutations in components of the Wnt/β-catenin signaling pathway, which occur commonly as early events in sporadic CRC. To examine this hypothesis, we evaluated possible associations between Wnt/β-catenin signaling and CCT based on the cancer stem cell (CSC) model. Wnt/β-catenin immunostaining indicated that UC patients have a level of Wnt-pathway-active cells that is intermediate between normal colon and CRC. These UC cells exhibiting activation of the Wnt pathway constituted a major subpopulation (52% + 7.21) of the colonic epithelial cells positive for aldehyde dehydrogenase (ALDH), a putative marker of precursor colon CSC (pCCSC). We further fractionated this subpopulation of pCCSC using a Wnt pathway reporter assay. Over successive passages, pCCSCs with the highest Wnt activity exhibited higher clonogenic and tumorigenic potential than pCCSCs with the lowest Wnt activity, thereby establishing the key role of Wnt activity in driving CSC-like properties in these cells. Notably, 5/20 single cell injections of high-Wnt pCCSC resulted in tumor formation, suggesting a correlation with CCT. Attenuation of Wnt/β-catenin in high-Wnt pCCSC by shRNA-mediated downregulation or pharmacological inhibition significantly reduced tumor growth rates. Overall, the results of our study indicates (i) that early activation of Wnt/β-catenin signaling is critical for CCT and (ii) that high levels of Wnt/β-catenin signaling can further demarcate high-ALDH tumor-initiating cells in the nondysplastic epithelium of UC patients. As such, our findings offer plausible diagnostic markers and therapeutic target in the

  20. An Analysis of Current Energy Policy Initiatives in New Mexico. What are the Potential Impacts to the State's Water Resources?

    NASA Astrophysics Data System (ADS)

    Klise, G. T.; Hart, W. E.; Kobos, P. H.; Malczynski, L. A.; Tidwell, V. C.

    2008-12-01

    Population in New Mexico is increasing rapidly with recent projections showing that the state will add more than 1 million people by 2035. This growth will create a demand for additional energy and water supplies that have yet to be developed. New Mexico currently exports about 50% of the energy generated within the state to neighboring states, and existing power plants predominately utilize traditional fossil fuels such as coal, oil and natural gas. Because traditional electric generation technologies utilize large quantities of water, New Mexico can also be seen as exporting water for the benefit of electricity consumed in neighboring states. As it is, both surface water and groundwater supplies are stretched thin and these internal and external stresses stemming from population growth will have a substantial impact on the state's water resources. In 2004, the Governor laid out a plan to make New Mexico a "Clean Energy State" by implementing renewable portfolio standards, developing renewable energy transmission infrastructure, creating an alternative energy innovation fund and creating state specific tax credits for renewable energy production and manufacturing. Recent work in the National Energy-Water Roadmap has pointed out that certain renewable sources of energy utilize less water than traditional power plants, and technological fixes to existing power plants will result in less water consumption. If New Mexico carries out its energy initiative, what will be the impacts to the state's water resources? Will it be possible to meet competing demands for this water? These questions and others will be analyzed in a decision-support tool that can look at the connection between both the physical and economic systems to see what the tradeoffs might be as a result of specific policy decisions. The ability to plan for future energy needs and understanding potential impacts to the state's limited water resources will be an invaluable tool for decision-makers in New

  1. Asphalt fume dermal carcinogenicity potential: II. Initiation-promotion assay of Type III built-up roofing asphalt.

    PubMed

    Freeman, James J; Schreiner, Ceinwen A; Beazley, S; Burnett, Donald M; Clark, Charles R; Mahagaokar, Suneeta; Parker, Craig M; Stewart, Christopher W; Swanson, Mark S; Arp, Earl W

    2011-10-01

    Clark et al. (accepted for publication) reported that a sample of field-matched fume condensate from a Type III built-up roofing asphalt (BURA) resulted in a carcinogenic response in a mouse skin bioassay, with relatively few tumor-bearing animals, long tumor latency and chronic skin irritation. This mouse skin initiation/promotion study was conducted to assess possible mechanisms, i.e., genotoxic initiation vs. tumor promotion subsequent to repeated skin injury and repair. The same Type III BURA fume condensate sample was evaluated in groups of 30 male Crl:CD1® mice by skin application twice per week (total dose of 50 mg/week) for 2 weeks during the initiation phase and for 26 weeks during the promotion phase. Positive control substances were 7,12-dimethylbenz(a)anthracene (DMBA, 50 μg applied once) as an initiator and 12-O-tetradecanoyl-13-acetate (TPA, 5 μg, applied twice weekly) during the promotion phase. During the 6 months of study with the asphalt fume condensate, eight skin masses were observed when tested for initiation, five of which were confirmed microscopically to be benign squamous cell papillomas. Only two papillomas were observed when tested for promotion. There was no apparent relationship between skin irritation and tumor development in this study. These results are more indicative of genotoxicity rather than a non-genotoxic mode of action. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. Global change impact on oxidative potential and toxicity of atmospheric particles from the East Mediterranean basin: the ARCHIMEDES initiative

    NASA Astrophysics Data System (ADS)

    Alleman, Laurent; Anthérieu, Sébastien; Baeza-Squiban, Armelle; Garçon, Guillaume; Lo Guidice, Jean-Marc; Hamonou, Eric; Öztürk, Fatma; Perdrix, Esperanza; Rudich, Yinon; Sciare, Jean; Sauvage, Stéphane

    2017-04-01

    Climate change (CC) has important social, economical and health implications, notably in accordance with variation in air pollution or microbiome modification and its related toxicity mechanisms. CC will have a strong influence on meteorology, inducing dryer and warmer conditions in some regions. The Mediterranean basin is foreseen as a hotspot for regional climate warming, favoring larger dust episodes, wild fire events, vegetation emissions and changes in air pollution physic-chemical characteristics due to enhanced photochemical reactivity. Increasing concentrations of biogenic volatile organic compounds (VOCs), ozone, and radicals will be associated with rising concentrations of secondary organic aerosols (SOA) and other oxidized aerosols. These expected changes in aerosol composition are currently studied within the international ChArMEx (Chemistry-aerosol Mediterranean Experiment) program, part of the interdisciplinary MISTRALS metaprogramme (Mediterranean Integrated STudies at Regional And Local Scales). According to the LIFE/MED-PARTICLES (LIFE) project, this might result in more adverse effects on health. However, toxicologists are far from having a detailed mechanistic knowledge of the quantitative causal relations between particles (PM) and health effects suggested by epidemiological evidences. Detailed toxicological studies looking at contrasted PM origins and chemical compositions are highly needed, particularly on strongly aged SOA suspected to increase the oxidative potential (OP) and to enhance the toxicity of airborne particles. Intensive researches onto the underlying mechanisms of inflammation started to describe the outlines of the intricate relationship between oxidative stress and inflammation. It is therefore, of great importance to better determine the OP of PM from contrasted surroundings, its relationship with CC through PM's physical, chemical and microbial characteristics, and its toxicological consequences within the lungs. Recently

  3. The White House BRAIN Initiative has the potential to further strengthen multidisciplinary research and training in psychology.

    PubMed

    Flattau, Pamela

    2014-12-01

    Comments on the original article by Robiner et al. (see record 2014-07939-001) regarding psychologists in medical schools and academic medical center settings. The current authors also discuss how to advance training in psychology using the Brain Research Through Advancing Innovative Neurotechnologies (BRAIN) Initiative. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  4. The German Dual System of Initial Vocational Education and Training and Its Potential for Transfer to Asia

    ERIC Educational Resources Information Center

    Hummelsheim, Stefan; Baur, Michaela

    2014-01-01

    Germany has a "dual system" of initial vocational education and training, one that other countries admire and would like to adopt. Can it hand this model over to them? This article argues that doing so will require far more than a simple process of copying. Instead, any transfer must reflect the existing conditions in the country…

  5. The German Dual System of Initial Vocational Education and Training and Its Potential for Transfer to Asia

    ERIC Educational Resources Information Center

    Hummelsheim, Stefan; Baur, Michaela

    2014-01-01

    Germany has a "dual system" of initial vocational education and training, one that other countries admire and would like to adopt. Can it hand this model over to them? This article argues that doing so will require far more than a simple process of copying. Instead, any transfer must reflect the existing conditions in the country…

  6. Building upon the Great Waters Initiative: Scoping study for potential polyaromatic hydrocarbon deposition into San Diego Bay

    SciTech Connect

    Koehler, J.; Sylte, W.W.

    1997-12-31

    The deposition of atmospheric polyaromatic hydrocarbons (PAHs) into San Diego Bay was evaluated at an initial study level. This study was part of an overall initial estimate of PAH waste loading to San Diego Bay from all environmental pathways. The study of air pollutant deposition to water bodies has gained increased attention both as a component of Total Maximum Daily Load (TMDL) determinations required under the Clean Water Act and pursuant to federal funding authorized by the 1990 Clean Air Act Amendments to study the atmospheric deposition of hazardous air pollutants to the Great Waters, which includes coastal waters. To date, studies under the Clean Air Act have included the Great Lakes, Chesapeake Bay, Lake Champlain, and Delaware Bay. Given the limited resources of this initial study for San Diego Bay, the focus was on maximizing the use of existing data and information. The approach developed included the statistical evaluation of measured atmospheric PAH concentrations in the San Diego area, the extrapolation of EPA study results of atmospheric PAH concentrations above Lake Michigan to supplement the San Diego data, the estimation of dry and wet deposition with published calculation methods considering local wind and rainfall data, and the comparison of resulting PAH deposition estimates for San Diego Bay with estimated PAH emissions from ship and commercial boat activity in the San Diego area. The resulting PAH deposition and ship emission estimates were within the same order of magnitude. Since a significant contributor to the atmospheric deposition of PAHs to the Bay is expected to be from shipping traffic, this result provides a check on the order of magnitude on the PAH deposition estimate. Also, when compared against initial estimates of PAH loading to San Diego Bay from other environmental pathways, the atmospheric deposition pathway appears to be a significant contributor.

  7. Modelling potential responses to severe acute respiratory syndrome in Japan: the role of initial attack size, precaution, and quarantine

    PubMed Central

    Nishiura, H; Patanarapelert, K; Sriprom, M; Sarakorn, W; Sriyab, S; Ming, T

    2004-01-01

    Background: There has been an outbreak of the severe acute respiratory syndrome (SARS) worldwide. With the use of detailed epidemiological data from other countries, this article describes the possible reason for the SARS epidemic not appearing in Japan, and simulates the impact of different control strategies that can break the transmission cycle of SARS associated coronavirus. Method: Mathematical modelling is used for predicting the epidemiological outcome and simultaneously for evaluating the effect of interventions on SARS. The study estimates the initial attack size that would result in failed invasion. Three different interventions have been incorporated into the public health response policies; precautionary public health measures, isolation of infected people, and quarantine of exposed humans. Results: The maximum number of humans newly infected could be roughly estimated on the basis of the initial attack size, using simple formulas. It is seen that the introduction of only a few cases into certain communities would not lead easily to an epidemic. The possible trajectories of SARS epidemic depend on the levels of public health interventions as quarantine and precautionary public health measures greatly affected the transmissibility of the disease. It is shown that there exist threshold levels of interventions at which the SARS epidemic settles down. Conclusion: Initial attack size is one of the determinants of whether SARS can successfully invade the community or not. Two of the most effective policy procedures to prevent new infections would be to apply stringent precautionary measures and to impose quicker and more effective quarantine of the exposed populace. PMID:14966229

  8. Initial Body Temperature in Ischemic Stroke: Non-Potentiation of TPA Benefit and Inverse Association with Severity

    PubMed Central

    Kim, Seo Hyun; Saver, Jeffrey L.

    2014-01-01

    Background and Purpose Body temperature (BT) is an important physiologic factor in acute ischemic stroke. However, the relation of initial BT to stroke severity and degree of benefit from thrombolytic therapy has been incompletely delineated. Methods We analyzed the public data set of the two National Institute of Neurological Disorders and Stroke tissue plaminogen activator (TPA) stroke trials, comparing patients with lower (<37.0°C) and higher (≥37.0°C) presenting BT. Results Among 595 patients (297 placebo- and 298 tPA-treated) with documented initial BT, 77.1% had initial BT <37.0°C and 22.9% ≥37.0°C. Patients with higher initial BT had lower baseline stroke severity in both tPA-treated patients (the National Institute of Health Stroke Scale median, 11 versus 15; p = 0.05) and placebo-treated patients (median, 13 versus 16; p <0.01). Patients with higher initial BT also had lower infarction volume on CT at 3 months in both tPA-treated patients (median, 9.6 versus 16.7 cm3; p = 0.08) and placebo-treated patients (median, 13.1 versus 28.1 cm3; p = 0.02), but no clinical outcome differences. Analysis of lytic treatment effect found no heterogeneity in the degree of tPA benefit in both higher and lower BT groups (≥37.0°C: odds ratio [OR] for the modified Rankin Scale 0-1 outcome 2.55, 95% confidence interval [CI] 1.05-6.21; <37.0°C: OR 2.30, 95% CI 1.38-3.84; heterogeneity p = 0.83). Conclusions In hyperacute stroke patients, higher presenting temperatures are associated with less severe neurological deficits and reduced final infarct volumes. Presenting temperature does not modify the benefit of tPA on 3-month favorable outcome. Clinical Trial Registration This trial was not registered because enrollment began prior to July 1, 2005. PMID:25424482

  9. Prognostic value of extravascular lung water and its potential role in guiding fluid therapy in septic shock after initial resuscitation.

    PubMed

    Wang, Hao; Cui, Na; Su, Longxiang; Long, Yun; Wang, Xiaoting; Zhou, Xiang; Chai, Wenzhao; Liu, Dawei

    2016-06-01

    To explore whether extravascular lung water (EVLW) provides a valuable prognostic tool guiding fluid therapy in septic shock patients after initial resuscitation. We performed a retrospective study of septic shock patients who achieved adequate initial fluid resuscitation with extended hemodynamic monitoring, analyzing the prognostic value of EVLW and whether fluid therapy for 24 (T24) or 24-48 hours (T24-48) after initial resuscitation with a recommended value of EVLW yielded a 28-day mortality advantage. One hundred five patients with septic shock were included in this study, 60 (57.1%) of whom died after 28 days. For 48 hours after initial resuscitation, the daily fluid balance (DFB; T24: 2494 ± 1091 vs 1965 ± 964 mL [P = .011] and T24-48: 2127 ± 783 vs 1588 ± 665 mL [P < .001]) and daily maximum values of the EVLW index (EVLWImax; T24: 13.9 ± 3.7 vs 11.5 ± 3.2 mL/kg [P < .001] and T24-48: 14.4 ± 5.3 vs 12.0 ± 4.4 mL/kg [P < .001]) were significantly higher in nonsurvivors than in survivors. In multivariate regression analysis, the DFB (T24: odds ratio [OR] 1.001 [P = .016] and T24-48: OR 1.001 [P = .008]), EVLWImax (T24: OR 2.158 [P = .002] and T24-48: OR 3.277 [P = .001]), blood lactate (T24: OR 1.368 [P = .021] and T24-48: OR 4.112 [P < .001]), and central venous blood oxygen saturation (T24: OR 0.893 [P = .013] and T24-48: OR 0.780 [P = .004]) were all independently associated with the 28-day mortality. A receiver operating characteristic analysis revealed that area under the curve values of 0.82 (95% confidence interval, 0.74-0.91; P < .001) and 0.90 (95% confidence interval, 0.83-0.96; P < .001) for EVLWImax ≥ 12.5 mL/kg (T24 and T24-48) predicted a 28-day mortality with sensitivities of 88% (80%-96%) and 95% (90%-100%) and specificities of 60% (46%-74%) and 76% (63%-89%).The EVLWImax was correlated with DFB with Spearman ρ values of 0.497 (T24: P < .001) and 0.650 (T24-48: P < .001). Cox survival and regression analyses demonstrated that

  10. Clean Energy Policy Analysis: Impact Analysis of Potential Clean Energy Policy Options for the Hawaii Clean Energy Initiative (HCEI)

    SciTech Connect

    Busche, S.; Doris, E.; Braccio, R.; Lippert, D.; Finch, P.; O'Toole, D.; Fetter, J.

    2010-04-01

    This report provides detailed analyses of 21 clean energy policy options considered by the Hawaii Clean Energy Initiative working groups for recommendation to the 2010 Hawaii State Legislature. The report considers the impact each policy may have on ratepayers, businesses, and the state in terms of energy saved, clean energy generated, and the financial costs and benefits. The analyses provide insight into the possible impacts, both qualitative and quantitative, that these policies may have in Hawaii based on the experience with these policies elsewhere. As much as possible, the analyses incorporate Hawaii-specific context to reflect the many unique aspects of energy use in the State of Hawaii.

  11. A potential protective mechanism of soya isoflavones against 7,12-dimethylbenz[a]anthracene tumour initiation.

    PubMed

    Chan, Ho Yee; Leung, Lai K

    2003-08-01

    Epidemiological studies indicate that Asian women have a lower breast cancer incidence compared with their counterparts in the West, and the difference has been related to soya consumption. Animal studies have suggested that soya may prevent dimethylbenz[a]anthracene (DMBA)-induced carcinogenesis in the breast. In the present study a cell culture model was developed to address the effect of soya isoflavones on the DMBA-induced DNA damage. DMBA is metabolized into a DNA-attacking moiety by two phase I cytochrome P450 (CYP) enzymes CYP1A1 and CYP1B1. DNA mutation caused by this genotoxic agent is a crucial step in cancer initiation. Substances that interfere with the CYP1 enzyme activities can affect the initiation. In the present study, genistein was found to be an effective inhibitor of recombinant human CYP1A1 and CYP1B1 with Ki of 15.35 and 0.68 micromol/l. The other soya isoflavone daidzein, on the other hand, did not demonstrate any significant inhibition of the enzyme activities. At the transcriptional level, DMBA induced the CYP1 enzyme expressions by stimulating the xenobiotic response element (XRE)-dependent transactivation pathway. When genistein (25 micromol/l) was co-administered with DMBA, the XRE-Luc activity the CYP1 mRNA abundances were significantly suppressed. The present study illustrated that the soya isoflavone genistein, but not daidzein, protected against DMBA genotoxicity.

  12. PTHrP drives breast tumor initiation, progression, and metastasis in mice and is a potential therapy target

    PubMed Central

    Li, Jiarong; Karaplis, Andrew C.; Huang, Dao C.; Siegel, Peter M.; Camirand, Anne; Yang, Xian Fang; Muller, William J.; Kremer, Richard

    2011-01-01

    Parathyroid hormone–related protein (PTHrP) is a secreted factor expressed in almost all normal fetal and adult tissues. It is involved in a wide range of developmental and physiological processes, including serum calcium regulation. PTHrP is also associated with the progression of skeletal metastases, and its dysregulated expression in advanced cancers causes malignancy-associated hypercalcemia. Although PTHrP is frequently expressed by breast tumors and other solid cancers, its effects on tumor progression are unclear. Here, we demonstrate in mice pleiotropic involvement of PTHrP in key steps of breast cancer — it influences the initiation and progression of primary tumors and metastases. Pthrp ablation in the mammary epithelium of the PyMT-MMTV breast cancer mouse model caused a delay in primary tumor initiation, inhibited tumor progression, and reduced metastasis to distal sites. Mechanistically, it reduced expression of molecular markers of cell proliferation (Ki67) and angiogenesis (factor VIII), antiapoptotic factor Bcl-2, cell-cycle progression regulator cyclin D1, and survival factor AKT1. PTHrP also influenced expression of the adhesion factor CXCR4, and coexpression of PTHrP and CXCR4 was crucial for metastatic spread. Importantly, PTHrP-specific neutralizing antibodies slowed the progression and metastasis of human breast cancer xenografts. Our data identify what we believe to be new functions for PTHrP in several key steps of breast cancer and suggest that PTHrP may constitute a novel target for therapeutic intervention. PMID:22056386

  13. An initial evaluation of potential options for managing riparian reserves of the Aquatic Conservation Strategy of the Northwest Forest Plan

    Treesearch

    Gordon H. Reeves; Brian R. Pickard; K. Norman. Johnson

    2016-01-01

    The Aquatic Conservation Strategy (ACS) of the Northwest Forest Plan guides management of riparian and aquatic ecosystems on federal lands in western Oregon, western Washington, and northern California. We applied new scientific findings and tools to evaluate two potential options, A and B, for refining interim riparian reserves to meet ACS goals and likely challenges...

  14. The Supplemental Security Income Program and the School-To-Work Transition Initiative: A National Assessment of Potential Eligibility.

    ERIC Educational Resources Information Center

    Berry, Hugh; Halloran, William

    Data from the 1992 Survey of Income and Program Participation (SIPP) were used to investigate the participation of young adults with disabilities between the ages of 18 through 26 (n=6,025,000) in the Supplemental Security Income (SSI) program. The study found that 33.4 percent of potentially eligible persons between 19 and 36 years old were found…

  15. A multicenter observational study of the potential benefits of initiating combination antiretroviral therapy during acute HIV infection.

    PubMed

    Hecht, Frederick M; Wang, Lei; Collier, Ann; Little, Susan; Markowitz, Martin; Margolick, Joseph; Kilby, J Michael; Daar, Eric; Conway, Brian; Holte, Sarah

    2006-09-15

    Uncontrolled studies have suggested a benefit, after treatment discontinuation, of initiating highly active antiretroviral therapy (HAART) during primary human immunodeficiency virus (HIV) infection. We assessed whether initiation of HAART within 2 weeks of (acute treatment) or between 2 weeks and 6 months after (early treatment) HIV seroconversion was associated with improvements in the viral load and the CD4+ T cell count after discontinuation of treatment in an observational cohort. Subjects from the multicenter Acute Infection and Early Disease Research Program cohort were enrolled in the present study within 6 months of HIV seroconversion and self-selected whether to initiate HAART. Subjects who received acute (n=13) or early (n=45) treatment received HAART for at least 12 weeks and then subsequently stopped treatment, whereas untreated subjects (n=337) declined treatment. HIV RNA levels and CD4+ T cell counts at 24, 48, and 72 weeks after treatment cessation in the 2 treatment groups were compared with those noted in the untreated group during the same periods of observation after enrollment. The acute treatment group had lower mean HIV RNA levels at 24 weeks without therapy (-0.48 log(10) copies/mL [95% confidence interval {CI}, -0.82 to -0.13 log(10) copies/mL]) and higher mean CD4+ T cell counts (112 cells/ mu L [95% CI, 20-205 cells/ microL]), compared with the untreated group at 24 weeks. The differences in the laboratory values for the acute treatment group versus the untreated group at 72 weeks without therapy were as follows: for the HIV RNA level, -0.35 log(10) copies/mL (95% CI, -0.91 to 0.21 log(10) copies/mL) and, for the CD4 T+ cell count, 112 cells/ microL (95% CI, -15 to 213 cells/ microL). The early treatment group had lower HIV RNA levels at 24 weeks than did the untreated group, but differences were no longer apparent by week 48; CD4+ T cell counts were higher in the early treatment group at week 24 (116 cells/ microL [95% CI, 75-157 cells

  16. Ionic regulation of the plasma membrane potential of rainbow trout (Salmo gairdneri) spermatozoa: Role in the initiation of sperm motility

    SciTech Connect

    Gatti, J.L.; Billard, R.; Christen, R. )

    1990-06-01

    The ionic dependence of the trout sperm plasma membrane potential was analysed by measuring the accumulation of the lipophilic ions {sup 3}H-tetraphenylphosphonium (TPP) and {sup 14}C-thiocyanate (SCN) following dilution in artificial media isotonic to the seminal fluid. Our data showed that the trout sperm plasma membrane has a mixed conductance: the plasma membrane potential is sensitive upon the transmembrane gradients of K+, Na+, and H+. This potential is negative (less than -40 mV) in a 125 mM choline chloride media (ChM) at pH 8.5. Replacement of choline by sodium has a small depolarizing effect. The membrane potential is about -15 mV in a 125 mM potassium chloride and falls near zero mV only if valinomycin is added. In ChM changing the external pH (pHe) greatly affects the membrane potential: its value rises from less than -40 mV at pHe 9.0 to -17 mV at pHe 5.0. This pH effect is observed also in presence of sodium or potassium. A decrease in the transmembrane proton gradient produced by increasing internal pH without changing pHe induces also a depolarisation of the plasma membrane. In the different media in which trout sperm remain immotile after dilution (media with (K+) greater than 20-40 mM or a pH less than 7.5) the plasma membrane is more depolarized than in media allowing motility, suggesting a relationship between the state of membrane polarization and the intracellular effectors of the axonemal movement.

  17. Effect of initiation-inhibition and handedness on the patterns of the P50 event-related potential component: a low resolution electromagnetic tomography study

    PubMed Central

    2009-01-01

    Background Recent research recognizes the association between handedness, linguistic processes and cerebral networks subserving executive functioning, but the nature of this association remains unclear. Since the P50 event related potential (ERP) is considered to reflect thalamocortical processes in association with working memory (WM) operation the present study focuses on P50 patterns elicited during the performance of a linguistic related executive functioning test in right- and left-handers. Methods In 64 young adults with a high educational level (33 left-handed) the P50 event-related potential was recorded while performing the initiation and inhibition condition of a modified version of the Hayling Sentence Completion test adjusted to induce WM. The manual preference of the participants was evaluated with the use of the Edinburgh Handedness Inventory (EHI). Results P50 showed greater amplitudes in left- than in right-handers, mainly in frontal leads, in the initiation condition. Reduced amplitudes in inhibition compared to initiation condition were observed in left-handers. Low Resolution Electromagnetic Tomography (LORETA) analysis showed lower frontal lobe activation in the inhibition than in the initiation condition in both right- and left-handers. Also, LORETA yielded that right-handers exhibited greater activation in the inhibition condition than left-handers. Additionally, LORETA showed assymetrical hemispheric activation patterns in right-handers, in contrast to symmetrical patterns observed in left-handers. Higher P50 amplitudes were recorded in right-hemisphere of right-handers in the initiation condition. Conclusion Brain activation, especially the one closely related to thalamocortical function, elicited during WM operation involving initiation and inhibition processes appears to be related to handedness. PMID:20034384

  18. Fusion of dendritic cells and CD34+CD38- acute myeloid leukemia (AML) cells potentiates targeting AML-initiating cells by specific CTL induction.

    PubMed

    Lei, Zhang; Zhang, Gui-Mei; Hong, Mei; Feng, Zuo-Hua; Huang, Bo

    2009-05-01

    Distinct leukemia-initiating cells (L-ICs) represent a critical target for therapeutic intervention of acute myeloid leukemia (AML). A potential strategy to eradicate L-ICs is to generate L-IC-specific cytotoxic T lymphocytes (CTLs). However, owing to rarity and immortality of L-ICs, it is difficult for antigen-presenting cells to capture L-ICs for specific antigen presentation. Here, we report a novel approach by fusing allogeneic dendritic cells (DCs) and CD34CD38 AML progenitor cells, through which specific CTLs were effectively induced, leading to the cytolysis to AML-initiating cells. Fusion of either DC/CD34CD38 AML cell or DC/CD34 AML cell could effectively induce the proliferation and activation of CTLs. However, only the former CTLs could effectively attack AML progenitor cells, and result in the unkilled progenitor/initiating cells losing the abilities of active proliferation in vitro and engraftment in NOD-SCID mice. These findings suggest that AML progenitor/initiating cell-specific CTLs may be generated based on allogeneic DC/progenitor cell fusion strategy; the induced CTLs may potentially eradicate AML by targeting L-ICs directly or indirectly.

  19. Revolutionary/Unconventional Aeropropulsion Technology Evaluation through Thermodynamic Work Potential: A Revolutionary Aeropropulsion Concepts Program Research Initiative

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri; Danner, Travis; Roth, Bryce

    2002-01-01

    This report is intended as a status report for activities covered May through July 2002 under the auspices of NASA Glenn's Revolutionary Aeropropulsion Concepts (RAC) project. This is the first phase I quarterly report and as such, considerable focus will be given to defining the basic need and motivation driving this research effort. In addition, background research has been ongoing for the past several months and has culminated in considerable information pertaining to the state-of-the-art in work potential analysis methods. This work is described in detail herein. Finally, the proposed analysis approach is described, as are the various ancillary concepts required for its implementation.

  20. Do transition towns have the potential to promote health and well-being? A health impact assessment of a transition town initiative.

    PubMed

    Richardson, J; Nichols, A; Henry, T

    2012-11-01

    Climate change and energy vulnerability present significant challenges for the development and sustainability of our communities. The adverse effects will most likely impact on those already experiencing poverty, as energy and food costs will rise, thus increasing inequalities in health. Transition town initiatives seek to build cohesive sustainable communities to prepare for a future with limited oil and a changing climate. Increasingly, public health practitioners are interested in the role of transition towns as a community development initiative, and their potential to support the wider public health agenda. Health impact assessment (HIA) is an evidence-based process that aims to predict the positive and negative impacts of a strategy, proposal or development. The HIA process provides an opportunity to promote sustainable communities by ensuring that new strategies and developments are considered in the context of their contribution to the health and well-being of local populations. The aim of this study was to use an HIA to examine the potential health and well-being benefits of two related transition town initiatives. A rapid HIA to consider the potential lifestyle changes and health and well-being impacts of Transition Together/Transition Streets (TT/TS) projects. An HIA template was used to assess key documents related to the TT/TS initiatives and those related to the characteristics of the community. Additionally, meetings with 12 key informants (four involved in TT/TS and eight purposively selected for their local knowledge) were held using the HIA template to focus the discussion. The findings highlight the associated lifestyle changes such as increased physical activity and healthy eating, and possible social and well-being benefits of engagement in such an initiative. Engagement may be limited to those already concerned about environmental issues. This paper illustrates the important links between transition towns and the wider public health agenda

  1. Impaired action potential initiation in GABAergic interneurons causes hyperexcitable networks in an epileptic mouse model carrying a human Na(V)1.1 mutation.

    PubMed

    Hedrich, Ulrike B S; Liautard, Camille; Kirschenbaum, Daniel; Pofahl, Martin; Lavigne, Jennifer; Liu, Yuanyuan; Theiss, Stephan; Slotta, Johannes; Escayg, Andrew; Dihné, Marcel; Beck, Heinz; Mantegazza, Massimo; Lerche, Holger

    2014-11-05

    Mutations in SCN1A and other ion channel genes can cause different epileptic phenotypes, but the precise mechanisms underlying the development of hyperexcitable networks are largely unknown. Here, we present a multisystem analysis of an SCN1A mouse model carrying the NaV1.1-R1648H mutation, which causes febrile seizures and epilepsy in humans. We found a ubiquitous hypoexcitability of interneurons in thalamus, cortex, and hippocampus, without detectable changes in excitatory neurons. Interestingly, somatic Na(+) channels in interneurons and persistent Na(+) currents were not significantly changed. Instead, the key mechanism of interneuron dysfunction was a deficit of action potential initiation at the axon initial segment that was identified by analyzing action potential firing. This deficit increased with the duration of firing periods, suggesting that increased slow inactivation, as recorded for recombinant mutated channels, could play an important role. The deficit in interneuron firing caused reduced action potential-driven inhibition of excitatory neurons as revealed by less frequent spontaneous but not miniature IPSCs. Multiple approaches indicated increased spontaneous thalamocortical and hippocampal network activity in mutant mice, as follows: (1) more synchronous and higher-frequency firing was recorded in primary neuronal cultures plated on multielectrode arrays; (2) thalamocortical slices examined by field potential recordings revealed spontaneous activities and pathological high-frequency oscillations; and (3) multineuron Ca(2+) imaging in hippocampal slices showed increased spontaneous neuronal activity. Thus, an interneuron-specific generalized defect in action potential initiation causes multisystem disinhibition and network hyperexcitability, which can well explain the occurrence of seizures in the studied mouse model and in patients carrying this mutation. Copyright © 2014 the authors 0270-6474/14/3414874-16$15.00/0.

  2. Impaired Action Potential Initiation in GABAergic Interneurons Causes Hyperexcitable Networks in an Epileptic Mouse Model Carrying a Human NaV1.1 Mutation

    PubMed Central

    Hedrich, Ulrike B.S.; Liautard, Camille; Kirschenbaum, Daniel; Pofahl, Martin; Lavigne, Jennifer; Liu, Yuanyuan; Theiss, Stephan; Slotta, Johannes; Escayg, Andrew; Dihné, Marcel; Beck, Heinz

    2014-01-01

    Mutations in SCN1A and other ion channel genes can cause different epileptic phenotypes, but the precise mechanisms underlying the development of hyperexcitable networks are largely unknown. Here, we present a multisystem analysis of an SCN1A mouse model carrying the NaV1.1-R1648H mutation, which causes febrile seizures and epilepsy in humans. We found a ubiquitous hypoexcitability of interneurons in thalamus, cortex, and hippocampus, without detectable changes in excitatory neurons. Interestingly, somatic Na+ channels in interneurons and persistent Na+ currents were not significantly changed. Instead, the key mechanism of interneuron dysfunction was a deficit of action potential initiation at the axon initial segment that was identified by analyzing action potential firing. This deficit increased with the duration of firing periods, suggesting that increased slow inactivation, as recorded for recombinant mutated channels, could play an important role. The deficit in interneuron firing caused reduced action potential-driven inhibition of excitatory neurons as revealed by less frequent spontaneous but not miniature IPSCs. Multiple approaches indicated increased spontaneous thalamocortical and hippocampal network activity in mutant mice, as follows: (1) more synchronous and higher-frequency firing was recorded in primary neuronal cultures plated on multielectrode arrays; (2) thalamocortical slices examined by field potential recordings revealed spontaneous activities and pathological high-frequency oscillations; and (3) multineuron Ca2+ imaging in hippocampal slices showed increased spontaneous neuronal activity. Thus, an interneuron-specific generalized defect in action potential initiation causes multisystem disinhibition and network hyperexcitability, which can well explain the occurrence of seizures in the studied mouse model and in patients carrying this mutation. PMID:25378155

  3. Investigating potential exogenous tumor initiating and promoting factors for Cutaneous T-Cell Lymphomas (CTCL), a rare skin malignancy.

    PubMed

    Litvinov, Ivan V; Shtreis, Anna; Kobayashi, Kenneth; Glassman, Steven; Tsang, Matthew; Woetmann, Anders; Sasseville, Denis; Ødum, Niels; Duvic, Madeleine

    2016-07-01

    Most skin malignancies are caused by external and often preventable environmental agents. Multiple reports demonstrated that cutaneous T-cell lymphomas (CTCL) can occur in married couples and cluster in families. Furthermore, recent studies document geographic clustering of this malignancy in Texas as well as in other areas of the United States. Multiple infectious, occupational, and medication causes have been proposed as triggers or promoters of this malignancy including hydrochlorothiazide diuretics, Staphylococcus aureus, dermatophytes, Mycobacterium leprae, Chlamydia pneumoniae, human T-Cell lymphotropic virus type 1 (HTLV1), Epstein-Barr virus (EBV), and herpes simplex virus (HSV). In this report, we review recent evidence evaluating the involvement of these agents in cancer initiation/progression. Most importantly, recent molecular experimental evidence documented for the first time that S. aureus can activate oncogenic STAT3 signaling in malignant T cells. Specifically, S. aureus Enterotoxin type A (SEA) was recently shown to trigger non-malignant infiltrating T cells to release IL-2 and other cytokines. These signals upon binging to their cognate receptors on malignant T cells are then able to activate STAT3 and STAT5 oncogenic signaling and promote cancer progression and IL-17 secretion. In light of these findings, it might be important for patients with exacerbation of their CTCL symptoms to maintain high index of suspicion and treat these individuals for S. aureus colonization and/or sepsis with topical and systemic antibiotics.

  4. Prokineticin 1 induces inflammatory response in human myometrium: a potential role in initiating term and preterm parturition.

    PubMed

    Gorowiec, Marta R; Catalano, Rob D; Norman, Jane E; Denison, Fiona C; Jabbour, Henry N

    2011-12-01

    The infiltration of human myometrium and cervix with leukocytes and the formation of a pro-inflammatory environment within the uterus have been associated with the initiation of both term and preterm parturition. The mechanism regulating the onset of this pro-inflammatory cascade is not fully elucidated. We demonstrate that prokineticin 1 (PROK1) is up-regulated in human myometrium and placenta during labor. The expression of PROK1 receptor remains unchanged during labor and is abundantly expressed in the myometrium. Gene array analysis identified 65 genes up-regulated by PROK1 in human myometrium, mainly cytokines and chemokines, including IL-1β, chemokine C-C motif ligand 3, and colony-stimulating factor 3. In addition, we demonstrate that PROK1 increases the expression of chemokine C-C motif ligand 20, IL-6, IL-8, prostaglandin synthase 2, and prostaglandin E(2) and F(2α) secretion. The treatment of myometrial explants with 100 ng/mL of lipopolysaccharide up-regulates the expression of PROK1, PROK1 receptor, and inflammatory mediators. The infection of myometrial explants with lentiviral microRNA targeting PROK1, preceding treatment with lipopolysaccharide, reduces the expression of inflammatory genes. We propose that PROK1 is a novel inflammatory mediator that can contribute to the onset of human parturition at term and partially mediate premature onset of inflammatory pathways during bacterial infection. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  5. Sources and flow patterns of deep-ocean waters as deduced from potential temperature, salinity, and initial phosphate concentration

    NASA Astrophysics Data System (ADS)

    Broecker, Wallace S.; Takahashi, Taro; Takahashi, Timothy

    1985-01-01

    Through the deconvolution of ocean chemical data it has been shown that the ratio of O2 utilization to phosphate production in the sea is 175±6 (rather than 138, as proposed by Redfield et al. (1963)). We find no evidence that this ratio changes significantly with location or depth in the sea. We have used this new ratio to calculate the initial phosphate concentrations for the waters sampled during the GEOSECS and TTO programs. The important application of these new results is in constraining the origin and flow patterns of deep waters in the ocean. We believe that a strong case can be made that Antarctic salinity maximum water (i.e., the common water of Montgomery (1958)) is produced by the mixing of waters entering the Antarctic from mid-depths in the Indian, Pacific, and Atlantic with Weddell Sea bottom water (southern component). Antarctic common water consists of about 45% Weddell Sea bottom water, 30% intermediate waters from the Pacific and Indian oceans, and 25% deep water originating from the northern Atlantic.

  6. Exploring action potential initiation in neurons exposed to DC electric fields through dynamical analysis of conductance-based model

    NASA Astrophysics Data System (ADS)

    Yi, Guo-Sheng; Wang, Jiang; Han, Chun-Xiao; Deng, Bin; Wei, Xi-Le; Jin, Qi-Tao

    2014-05-01

    Noninvasive direct current (DC) electric stimulation of central nervous system is today a promising therapeutic option to alleviate the symptoms of a number of neurological disorders. Despite widespread use of this noninvasive brain modulation technique, a generalizable explanation of its biophysical basis has not been described which seriously restricts its application and development. This paper investigated the dynamical behaviors of Hodgkin's three classes of neurons exposed to DC electric field based on a conductance-based neuron model. With phase plane and bifurcation analysis, the different responses of each class of neuron to the same stimulation are shown to derive from distinct spike initiating dynamics. Under the effects of negative DC electric field, class 1 neuron generates repetitive spike through a saddle-node on invariant circle (SNIC) bifurcation, while it ceases this repetitive behavior through a Hopf bifurcation; Class 2 neuron generates repetitive spike through a Hopf bifurcation, meanwhile it ceases this repetitive behavior also by a Hopf bifurcation; Class 3 neuron can generate single spike through a quasi-separatrix-crossing (QSC) at first, then it generates repetitive spike through a Hopf bifurcation, while it ceases this repetitive behavior through a SNIC bifurcation. Furthermore, three classes of neurons' spiking frequency f-electric field E (f-E) curves all have parabolic shape. Our results highlight the effects of external DC electric field on neuronal activity from the biophysical modeling point of view. It can contribute to the application and development of noninvasive DC brain modulation technique.

  7. A vertical hydroclimatology of the Upper Indus Basin and initial insights to potential hydrological change in the region

    NASA Astrophysics Data System (ADS)

    Forsythe, Nathan; Kilsby, Chris G.; Fowler, Hayley J.; Archer, David R.

    2010-05-01

    The water resources of the Upper Indus Basin (UIB) are of the utmost importance to the economic wellbeing of Pakistan. The irrigated agriculture made possible by Indus river runoff underpins the food security for Pakistan's nearly 200 million people. Contributions from hydropower account for more than one fifth of peak installed electrical generating capacity in a country where widespread, prolonged load-shedding handicaps business activity and industrial development. Pakistan's further socio-economic development thus depends largely on optimisation of its precious water resources. Confident, accurate projections of future water resource availability and variability are urgent insights needed by development planners and infrastructure managers at all levels. Correctly projecting future hydrological conditions depends first and foremost on a thorough understanding of the underlying mechanisms and processes of present hydroclimatology. The vertical and horizontal spatial variations in key climate parameters (temperature, precipitation) govern the contributions of the various elevation zones and subcatchments comprising the UIB. Trends in this complex mountainous region are highly varied by season and parameter. Observed changes here often do not match general global trends or even necessarily those found in neighbouring regions. This study considers data from a variety sources in order to compose the most complete picture possible of the vertical hydroclimatology of the UIB. The study presents the observed climatology and trends for precipitation and temperature from local observations at long-record meteorological stations (Pakistan Meteorological Department). These data are compared to characterisations of additional water cycle parameters (humidity, cloud, snow cover and snow-water-equivalent) derived from local short-record automatic weather stations, the ECMWF ‘ERA' reanalysis projects and satellite based observations (AVHRR, MODIS, etc). The potential

  8. SU-C-204-07: Radiation Therapy as a Potential Treatment for Obesity: Initial Data from a Preclinical Investigation

    SciTech Connect

    Pasciak, A; Bradley, Y; Nodit, L; Bourgeois, A; Paxton, B; Arepally, A

    2016-06-15

    Purpose: To evaluate the feasibility of Yttrium-90 (90Y) radionuclide therapy as a potential treatment for obesity in a porcine model. As the only appetite-stimulating hormone, localized targeting of ghrelin-producing X/A cells in the fundus of the stomach using 90Y may reduce serum ghrelin levels and decrease hunger. Methods: Under approval of the University of Tennessee IACUC, 8 young female pigs aged 12–13 weeks and weighing 21.8–28.1 Kg were included in this study. Six animals underwent transfemoral angiography as part of a two-day procedure involving: (1) infusion of 99mTc-MAA, followed by nuclear scintigraphy and contrast-enhanced CT for treatment-planning and (2) administration of resin 90Y microspheres into the stomach fundus. Calibrated 90Y activities were infused into the main left gastric and the gastric artery arising from the splenic to yield predetermined fundal absorbed doses. Control animals underwent a sham procedure with saline and contrast. Weekly animal weight and serum ghrelin were measured along with post-euthanasia histologic analyses of mucosal integrity and ghrelin immunoreactive cell-density. Results: 90Y radioembolization was administered to six pigs in dosages from 46.3 to 105.1 MBq resulting in average fundal absorbed doses between 35.5 and 91.9 Gy. No animal showed any signs of pain or GI complication through the duration of the study. Ghrelin immunoreactive cell-density was significantly lower in treated vs. control animals in both the stomach fundus (13.5 vs 34.8, P < 0.05) and body (11.2 vs 19.8, P < 0.05). A trend towards decreased weight gain in treated animals as well as a decrease in explanted stomach volume was also noted. Conclusion: The safety and technical feasibility of radiation therapy using 90Y radioembolization as a potential treatment for obesity has been demonstrated at fundal absorbed doses over 90 Gy. Preliminary data is suggestive of short-term safety and potential efficacy, however, further animal studies are

  9. Initial validation of a proxy indicator of functioning as a potential tool for establishing a clinically meaningful cocaine use outcome.

    PubMed

    Kiluk, Brian D; Babuscio, Theresa A; Nich, Charla; Carroll, Kathleen M

    2017-10-01

    Establishing a non-abstinence cocaine use outcome as clinically meaningful has been elusive, in part due to the lack of association between cocaine use outcomes and meaningful indicators of long-term functioning. Using data pooled across 7 clinical trials evaluating treatments for cocaine (N=718), a dichotomous indicator of functioning was created to represent a meaningful outcome ('problem-free functioning' - PFF), defined as the absence of problems across non-substance-related domains on the Addiction Severity Index. Its validity was evaluated at multiple time points (baseline, end-of-treatment, terminal follow-up) and used to explore associations with cocaine use. The percentage of participants meeting PFF criteria increased over time (baseline=18%; end-of-treatment=32%; terminal follow-up=37%). At each time point, ANOVAs indicated those who met PFF criteria reported significantly less distress on the Brief Symptom Inventory and less perceived stress on the Perceived Stress Scale. Generalized linear models indicated categorical indices of self-reported cocaine use at the end of treatment were predictive of the probability of meeting PFF criteria during follow-up (β=-0.01, p<0.01; 95% CI: -0.008 to -0.003), with those reporting 0days or 1-4days ('occasional' use) in the final month of treatment showing an increased likelihood of achieving PFF. Initial validation of a proxy indicator of problem-free functioning demonstrated criterion validity and sensitivity to change over time. Frequency of cocaine use in the final month of treatment was associated with PFF during follow-up, with strongest associations between PFF and abstinence or 'occasional' use. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. The potential role of CO2 in initiation and maintenance of estivation in the land snail Helix lucorum.

    PubMed

    Michaelidis, Basile; Vavoulidou, Dimitra; Rousou, Jenia; Pörtner, Hans O

    2007-01-01

    Elevated CO(2) levels are hypothesized to play a role in the initiation and maintenance of estivation in snails through disturbances of acid-base status. The aim of our study was to identify the ambient CO(2) threshold that induces disturbances in acid-base status in the air-breathing land snail Helix lucorum. Acid-base parameters were determined in the hemolymph of snails acclimated to 0.5%, 1%, 2%, 4%, and 8% CO(2) in air for 20 d. In addition, we evaluated the effects of long-term acclimation on metabolic rate and on levels of D-lactate dehydrogenase activity (D-LDH) and of D-lactate in snails after 20 d of exposure to increased CO(2) levels. Helix lucorum proved to be unable to compensate for a decrease in extracellular pH (pH(e)) when acclimated to levels higher than 1% CO(2) in air. The rate of oxygen consumption started to decrease when snails were acclimated to 0.5% CO(2) in air. However, there was no correlation between the drops in pH(e) and in metabolic rate. Long-term acclimation to elevated CO(2) levels induced an increase in the activity of D-LDH with a concomitant accumulation of D-lactate in tissues. This indicates that long-term acclimation to elevated ambient CO(2) levels could reduce the aerobic capacity of land snails and trigger expression of anaerobic pathways of ATP turnover. The threshold levels of ambient CO(2) that induce changes in acid-base status and elicit metabolic depression in adult land snails H. lucorum are higher than the future atmospheric levels that are expected to result from human use of fossil energy resources.

  11. Communication: Estimating the initial biasing potential for λ-local-elevation umbrella-sampling (λ-LEUS) simulations via slow growth

    SciTech Connect

    Bieler, Noah S.; Hünenberger, Philippe H.

    2014-11-28

    In a recent article [Bieler et al., J. Chem. Theory Comput. 10, 3006–3022 (2014)], we introduced a combination of the λ-dynamics (λD) approach for calculating alchemical free-energy differences and of the local-elevation umbrella-sampling (LEUS) memory-based biasing method to enhance the sampling along the alchemical coordinate. The combined scheme, referred to as λ-LEUS, was applied to the perturbation of hydroquinone to benzene in water as a test system, and found to represent an improvement over thermodynamic integration (TI) in terms of sampling efficiency at equivalent accuracy. However, the preoptimization of the biasing potential required in the λ-LEUS method requires “filling up” all the basins in the potential of mean force. This introduces a non-productive pre-sampling time that is system-dependent, and generally exceeds the corresponding equilibration time in a TI calculation. In this letter, a remedy is proposed to this problem, termed the slow growth memory guessing (SGMG) approach. Instead of initializing the biasing potential to zero at the start of the preoptimization, an approximate potential of mean force is estimated from a short slow growth calculation, and its negative used to construct the initial memory. Considering the same test system as in the preceding article, it is shown that of the application of SGMG in λ-LEUS permits to reduce the preoptimization time by about a factor of four.

  12. Communication: Estimating the initial biasing potential for λ-local-elevation umbrella-sampling (λ-LEUS) simulations via slow growth

    NASA Astrophysics Data System (ADS)

    Bieler, Noah S.; Hünenberger, Philippe H.

    2014-11-01

    In a recent article [Bieler et al., J. Chem. Theory Comput. 10, 3006-3022 (2014)], we introduced a combination of the λ-dynamics (λD) approach for calculating alchemical free-energy differences and of the local-elevation umbrella-sampling (LEUS) memory-based biasing method to enhance the sampling along the alchemical coordinate. The combined scheme, referred to as λ-LEUS, was applied to the perturbation of hydroquinone to benzene in water as a test system, and found to represent an improvement over thermodynamic integration (TI) in terms of sampling efficiency at equivalent accuracy. However, the preoptimization of the biasing potential required in the λ-LEUS method requires "filling up" all the basins in the potential of mean force. This introduces a non-productive pre-sampling time that is system-dependent, and generally exceeds the corresponding equilibration time in a TI calculation. In this letter, a remedy is proposed to this problem, termed the slow growth memory guessing (SGMG) approach. Instead of initializing the biasing potential to zero at the start of the preoptimization, an approximate potential of mean force is estimated from a short slow growth calculation, and its negative used to construct the initial memory. Considering the same test system as in the preceding article, it is shown that of the application of SGMG in λ-LEUS permits to reduce the preoptimization time by about a factor of four.

  13. Toward panoramic in situ mapping of action potential propagation in transgenic hearts to investigate initiation and therapeutic control of arrhythmias

    PubMed Central

    Dura, Miroslav; Schröder-Schetelig, Johannes; Luther, Stefan; Lehnart, Stephan E.

    2014-01-01

    To investigate the dynamics and propensity for arrhythmias in intact transgenic hearts comprehensively, optical strategies for panoramic fluorescence imaging of action potential (AP) propagation are essential. In particular, mechanism-oriented molecular studies usually depend on transgenic mouse hearts of only a few millimeters in size. Furthermore, the temporal scales of the mouse heart remain a challenge for panoramic fluorescence imaging with heart rates ranging from 200 min−1 (e.g., depressed sinus node function) to over 1200 min−1 during fast arrhythmias. To meet these challenging demands, we and others developed physiologically relevant mouse models and characterized their hearts with planar AP mapping. Here, we summarize the progress toward panoramic fluorescence imaging and its prospects for the mouse heart. In general, several high-resolution cameras are synchronized and geometrically arranged for panoramic voltage mapping and the surface and blood vessel anatomy documented through image segmentation and heart surface reconstruction. We expect that panoramic voltage imaging will lead to novel insights about molecular arrhythmia mechanisms through quantitative strategies and organ-representative analysis of intact mouse hearts. PMID:25249982

  14. An initial examination of the potential role of T-cell immunity in protection against feline immunodeficiency virus (FIV) infection.

    PubMed

    Aranyos, Alek M; Roff, Shannon R; Pu, Ruiyu; Owen, Jennifer L; Coleman, James K; Yamamoto, Janet K

    2016-03-14

    potentially HIV-1.

  15. An initial examination of the potential role of T-cell immunity in protection against feline immunodeficiency virus (FIV) infection

    PubMed Central

    Aranyos, Alek M.; Roff, Shannon R.; Pu, Riuyu; Owen, Jennifer L.; Coleman, James K.; Yamamoto, Janet K.

    2016-01-01

    The importance of vaccine-induced T-cell immunity in conferring protection with prototype and commercial FIV vaccines is still unclear. Current studies performed adoptive transfer of T cells from prototype FIV-vaccinated cats to partial-to-complete feline leukocyte antigen (FLA)-matched cats a day before either homologous FIVPet or heterologous-subtype pathogenic FIVFC1 challenge. Adoptive-transfer (A–T) conferred a protection rate of 87% (13 of 15, p<0.001) against FIVPet using FLA-matched T cells, whereas all 12 control cats were unprotected. Furthermore, A-T conferred protection rate of 50% (6 of 12, p<0.023) against FIVFC1 using FLA-matched T cells, whereas all 8 control cats were unprotected. Transfer of FLA-matched T and B cells demonstrated that T cells are needed to confer A-T protection. In addition, complete FLA-matching and addition of T-cell numbers >13×106 cells were required for A-T protection against FIVFC1 strain, reported to be a highly pathogenic virus resistant to vaccine-induced neutralizing-antibodies. The addition of FLA-matched B cells alone was not protective. The poor quality of the anti-FIV T-cell immunity induced by the vaccine likely contributed to the lack of protection in an FLA-matched recipient against FIVFC1. The quality of the immune response was determined by the presence of high mRNA levels of cytolysin (perforin) and cytotoxins (granzymes A, B, and H) and T helper-1 cytokines (interferon-γ [IFNγ] and IL2). Increased cytokine, cytolysin and cytotoxin production was detected in the donors which conferred protection in A-T studies. In addition, the CD4+ and CD8+ T-cell proliferation and/or IFNγ responses to FIV p24 and reverse transcriptase increased with each year in cats receiving 1X-3X vaccine boosts over 4 years. These studies demonstrate that anti-FIV T-cell immunity induced by vaccination with a dual-subtype FIV vaccine is essential for prophylactic protection against AIDS lentiviruses such as FIV and potentially HIV-1

  16. Potential use of cubic phase masks for extending the range of clear vision in presbyopes: initial calculation and simulation studies.

    PubMed

    Arines, Justo; Almaguer, Citlalli; Acosta, Eva

    2017-03-01

    In this paper we analyse the potential use of a non-symmetrical optical element, a cubic phase mask, for extending the range of clear vision of presbyopic eyes. Additionally, we will discuss the appropriateness of the visual Strehl ratio to analyse this sort of presbyopic solution based on non-symmetrical phase masks contrasted with through-focus retinal images. In order to evaluate the performance of the cubic phase mask we employed computational Fourier Optics to compute the different visual Strehl criteria as well as simulate the retinal images. The through focus real part of the modulation transfer functions and retinal images were computed for four object distances 6.0, 1.0, 0.6 and 0.4 m which correspond to far, intermediate and near vision conditions for optotypes of visual acuity of 0.1 and 0.0 logMAR (Snellen 6/7.5 and 6/6; 0.8 and 1 in decimal Snellen). For the experimental validation we built an artificial eye consisting of a plano-convex lens with a focal length of 25.4 mm and 0.5 numerical aperture, a variable diaphragm, a 3× objective and an ORCA 285 Hamamatsu Photonics camera 8.1 μm pixel size (resulting in an effective pixel size of 2.7 μm). A set of four different VA charts adapted to monitor different visual acuities (ranging between 0.0 and 0.20 logMAR) were placed at different object distances 6, 1.0, 0.6 and 0.4 m from the artificial eye. Both numerical and experimental validation showed the suitability of the cubic phase mask for extending the range of clear vision of presbyopic eyes, providing at least a visual acuity of 0.1 logMAR (6/7.5 Snellen, 0.8 decimal Snellen) at all distances. The results show that it is possible to choose between promoting far or near vision by changing the magnitude of the defocus component. It is also possible to extend the range of clear vision, by increasing the magnitude of the cubic component. But this increment will cause a reduction in the contrast of the images as it can be observed from the Visual

  17. Developing New Alternative Energy in Virginia: Bio-Diesel from Algae

    SciTech Connect

    Hatcher, Patrick

    2012-03-29

    The overall objective of this study was to select chemical processing equipment, install and operate that equipment to directly convert algae to biodiesel via a reaction patented by Old Dominion University (Pat. No. US 8,080,679B2). This reaction is a high temperature (250- 330{degrees}C) methylation reaction utilizing tetramethylammonium hydroxide (TMAH) to produce biodiesel. As originally envisioned, algal biomass could be treated with TMAH in methanol without the need to separately extract triacylglycerides (TAG). The reactor temperature allows volatilization and condensation of the methyl esters whereas the spent algae solids can be utilized as a high-value fertilizer because they are minimally charred. During the course of this work and immediately prior to commencing, we discovered that glycerol, a major by-product of the conventional transesterification reaction for biofuels, is not formed but rather three methoxylated glycerol derivatives are produced. These derivatives are high-value specialty green chemicals that strongly upgrade the economics of the process, rendering this approach as one that now values the biofuel only as a by-product, the main value products being the methoxylated glycerols. A horizontal agitated thin-film evaporator (one square foot heat transfer area) proved effective as the primary reactor facilitating the reaction and vaporization of the products, and subsequent discharge of the spent algae solids that are suitable for supplementing petrochemicalbased fertilizers for agriculture. Because of the size chosen for the reactor, we encountered problems with delivery of the algal feed to the reaction zone, but envision that this problem could easily disappear upon scale-up or can be replaced economically by incorporating an extraction process. The objective for production of biodiesel from algae in quantities that could be tested could not be met, but we implemented use of soybean oil as a surrogate TAG feed to overcome this limitation. The positive economics of this process are influenced by the following: 1. the weight percent of dry algae in suspension that can be fed into the evaporator, 2. the alga species’ ability to produce a higher yield of biodiesel, 3. the isolation of valuable methoxylated by-products, 4. recycling and regeneration of methanol and TMAH, and 5. the market value of biodiesel, commercial agricultural fertilizer, and the three methoxylated by-products. The negative economics of the process are the following: 1. the cost of producing dried, ground algae, 2. the capital cost of the equipment required for feedstock mixing, reaction, separation and recovery of products, and reactant recycling, and 3. the electrical cost and other utilities. In this report, the economic factors and results are assembled to predict the commercialization cost and its viability. This direct conversion process and equipment discussed herein can be adapted for various feedstocks including: other algal species, vegetable oil, jatropha oil, peanut oil, sunflower oil, and other TAG containing raw materials as a renewable energy resource.

  18. Esterfip, a transesterification process to produce bio-diesel from renewable energy sources

    SciTech Connect

    Hennico, A.; Chodorge, J.A.; Forestiere, A.

    1995-12-31

    Vegetables oils and products synthesized from natural raw materials (either of vegetable or animal origin) are having a strong {open_quotes}come back{close_quotes} in the recent decades. One of the major reasons for the increased utilization of fatty chemicals for industrial use has been the ability to tailor the products to specific needs. This trends is clearly indicated in Table 1 that gives an estimate of the world fat production in millions tons and in the case of vegetable oils, the yields per unit area (hectare) per year. End uses of upgraded products or derivative compounds are extremely numerous but usually highly specialized. Major areas of applications are: Food industry, soap and detergents, cosmetics, pharmaceuticals, textile and paper industry, oil field chemicals, fat based emulsifiers, synthetic lubricants, metal working fluids and last but not least introduction into the automotive fuel sector. This last application will be the subject of this presentation.

  19. Test of a Potential Causal Influence of Earlier Age of Gambling Initiation on Gambling Involvement and Disorder: A Multi-level Discordant Twin Design

    PubMed Central

    Slutske, Wendy S.; Deutsch, Arielle R.; Richmond-Rakerd, Leah S.; Chernyavskiy, Pavel; Statham, Dixie J.; Martin, Nicholas G.

    2014-01-01

    The premise that an association between an earlier age of gambling initiation and the later development of disordered gambling is causal has not yet been empirically examined. The current study used a multi-level discordant twin design to examine the nature of this association. Participants were 3,546 same-sex twins (mean age = 37.7 years) from the Australian Twin Registry who completed a telephone interview that included an extensive assessment of gambling and related behaviors. Multilevel models were employed to estimate individual (within-twin-pair comparison) and family-level (between-twin-pair comparison) effects, as well as the cross-level interaction between these effects. Family-level effects (genetic or environmental factors shared by family members) of age of gambling initiation robustly predicted later adult gambling frequency and disorder; the evidence for individual-level effects (unique factors not shared by family members, including a potentially causal effect of earlier age of gambling onset) was less robust. The results of this study suggest that the relation between earlier age of gambling initiation and later gambling involvement and disorder is primarily non-causal; efforts to delay the onset of gambling among young people may not necessarily reduce the number who later go on to develop gambling-related problems. PMID:24635489

  20. [Initial positive deflection of the compound muscle action potential in the median nerve conduction studies can be originated from lumbrical muscles in patients with carpal tunnel syndrome].

    PubMed

    Matsumoto, S; Hasegawa, O

    2000-05-01

    In motor nerve conduction studies we sometimes encounter a small initial positive deflection (IPD) of the compound muscle action potential (CMAP). This potential represents a volume conduction from nearby muscles other than the objective muscle. We demonstrated recordings of motor nerve conduction studies from two patients with carpal tunnel syndrome (CTS). In patients with CTS IPDs can be recorded from a surface electrode above the abductor pollicis brevis when intense stimuli to the median nerve provoked a stimulus spread to the ulnar nerve. However, without this stimulus spread to the ulnar nerve, IPDs can be observed by contraction of median nerve innervated muscles. In the CTS thenar branch of the median nerve is apt to be more severely damaged than lumbrical branch. In such an occasion volume conduction from the lumbrical muscles is relatively large, which gives rise to the IPD in the CMAP recorded from abductor pollicis brevis. We reported two cases of IDPs originated from lumbrical muscles. The peak latencies were identical between IDP of abductor pollicis brevis recording and negative potential of lumbrical recording. These potentials didn't change by median nerve stimulation at the elbow 3 msec after the ulnar nerve stimulation at the wrist (collision technique). Finally, we repeat that IPDs in the median nerve conduction studies can be originated from not only the stimulus spread to the ulnar nerve but also the median nerve innervated lumbrical muscles in patients with CTS.

  1. Priming of endothelial colony-forming cells in a mesenchymal niche improves engraftment and vasculogenic potential by initiating mesenchymal transition orchestrated by NOTCH signaling.

    PubMed

    Shafiee, Abbas; Patel, Jatin; Wong, Ho Yi; Donovan, Prudence; Hutmacher, Dietmar W; Fisk, Nicholas M; Khosrotehrani, Kiarash

    2017-02-01

    The prospect of using endothelial progenitors is currently hampered by their low engraftment upon transplantation. We report that mesenchymal stem/stromal cells (MSCs), independent of source and age, improve the engraftment of endothelial colony forming cells (ECFCs). MSC coculture altered ECFC appearance to an elongated mesenchymal morphology with reduced proliferation. ECFC primed via MSC contact had reduced self-renewal potential, but improved capacity to form tube structures in vitro and engraftment in vivo Primed ECFCs displayed major differences in transcriptome compared to ECFCs never exposed to MSCs, affecting genes involved in the cell cycle, up-regulating of genes influencing mesenchymal transition, adhesion, extracellular matrix. Inhibition of NOTCH signaling, a potential upstream regulator of mesenchymal transition, in large part modulated this gene expression pattern and functionally reversed the mesenchymal morphology of ECFCs. The collective results showed that primed ECFCs survive better and undergo a mesenchymal transition that is dependent on NOTCH signaling, resulting in significantly increased vasculogenic potential.-Shafiee, A., Patel, J., Wong, H. Y., Donovan, P., Hutmacher, D. W., Fisk, N. M., Khosrotehrani, K. Priming of endothelial colony-forming cells in a mesenchymal niche improves engraftment and vasculogenic potential by initiating mesenchymal transition orchestrated by NOTCH signaling.

  2. Initial segment Kv2.2 channels mediate a slow delayed rectifier and maintain high frequency action potential firing in medial nucleus of the trapezoid body neurons.

    PubMed

    Johnston, Jamie; Griffin, Sarah J; Baker, Claire; Skrzypiec, Anna; Chernova, Tatanya; Forsythe, Ian D

    2008-07-15

    The medial nucleus of the trapezoid body (MNTB) is specialized for high frequency firing by expression of Kv3 channels, which minimize action potential (AP) duration, and Kv1 channels, which suppress multiple AP firing, during each calyceal giant EPSC. However, the outward K(+) current in MNTB neurons is dominated by another unidentified delayed rectifier. It has slow kinetics and a peak conductance of approximately 37 nS; it is half-activated at -9.2 +/- 2.1 mV and half-inactivated at -35.9 +/- 1.5 mV. It is blocked by several non-specific potassium channel antagonists including quinine (100 microm) and high concentrations of extracellular tetraethylammonium (TEA; IC(50) = 11.8 mM), but no specific antagonists were found. These characteristics are similar to recombinant Kv2-mediated currents. Quantitative RT-PCR showed that Kv2.2 mRNA was much more prevalent than Kv2.1 in the MNTB. A Kv2.2 antibody showed specific staining and Western blots confirmed that it recognized a protein approximately 110 kDa which was absent in brainstem tissue from a Kv2.2 knockout mouse. Confocal imaging showed that Kv2.2 was highly expressed in axon initial segments of MNTB neurons. In the absence of a specific antagonist, Hodgkin-Huxley modelling of voltage-gated conductances showed that Kv2.2 has a minor role during single APs (due to its slow activation) but assists recovery of voltage-gated sodium channels (Nav) from inactivation by hyperpolarizing interspike potentials during repetitive AP firing. Current-clamp recordings during high frequency firing and characterization of Nav inactivation confirmed this hypothesis. We conclude that Kv2.2-containing channels have a distinctive initial segment location and crucial function in maintaining AP amplitude by regulating the interspike potential during high frequency firing.

  3. A retrospective, matched cohort study of potential drug-drug interaction prevalence and opioid utilization in a diabetic peripheral neuropathy population initiated on pregabalin or duloxetine.

    PubMed

    Ellis, Jeffrey J; Sadosky, Alesia B; Ten Eyck, Laura L; Mudumby, Pallavi; Cappelleri, Joseph C; Ndehi, Lilian; Suehs, Brandon T; Parsons, Bruce

    2015-04-15

    Anticipating and controlling drug-drug interactions (DDIs) in older patients with painful diabetic peripheral neuropaty (pDPN) presents a significant challenge to providers. The purpose of this study was to examine the impact of newly initiated pregabalin or duloxetine treatment on Medicare Advantage Prescription Drug (MAPD) plan pDPN patients' encounters with potential drug-drug interactions, the healthcare cost and utilization consequences of those interactions, and opioid utilization. Study subjects required a pregabalin or duloxetine pharmacy claim between 07/01/2008-06/30/2012 (index event), ≥1 inpatient or ≥2 outpatient medical claims with pDPN diagnosis between 01/01/2008-12/31/2012, and ≥12 months pre- and ≥6 post-index enrollment. Propensity score matching was used to balance the pregabalin and duloxetine cohorts on pre-index demographics and comorbidities. Potential DDIs were defined by Micromedex 2.0 and identified by prescription claims. Six-month post-index healthcare utilization (HCU) and costs were calculated using pharmacy and medical claims. No significant differences in pre-index demographics or comorbidities were found between pregabalin subjects (n = 446) and duloxetine subjects (n = 446). Potential DDI prevalence was significantly greater (p < 0.0001) among duoxetine subjects (56.7%) than among pregabalin subjects (2.9%). There were no significant differences in HCU or costs between pregablin subjects with and without a potential DDI. By contrast, duloxetine subjects with a potential DDI had higher mean all-cause costs ($13,908 vs. $9,830; p = 0.001), more subjects with ≥1 inpatient visits (35.6% vs 25.4%; p = 0.02), and more subjects with ≥1 emergency room visits (32.8% vs. 20.7%; p = 0.005) in comparison to duloxetine subjects without a potential DDI. There was a trend toward a difference between pregabalin and duloxetine subjects in their respective pre-versus-post differences in milligrams (mg) of

  4. Potential Impacts of Leakage from Black Rock Reservoir on the Hanford Site Unconfined Aquifer: Initial Hypothetical Simulations of Flow and Contaminant Transport

    SciTech Connect

    Freedman, Vicky L.

    2007-03-09

    Initial scoping calculations of the unconfined aquifer at the Hanford Site were carried out for the U.S. Bureau of Reclamation (USBR) to investi¬gate the potential impacts on the Hanford unconfined aquifer that would result from leakage from the proposed Black Rock Reservoir to the west. Although impacts on groundwater flow and contaminant transport were quantified based on numerical simulation results, the investigation represented a quali¬tative assessment of the potential lateral recharge that could result in adverse effects on the aquifer. Because the magnitude of the potential leakage is unknown, hypothetical bounding calculations were performed. When a quantitative analysis of the magnitude of the potential recharge from Black Rock Reservoir is obtained, the hydrologic impacts analysis will be revisited. The analysis presented in this report represent initial bounding calculations. A maximum lateral recharge (i.e., upland flux) was determined in the first part of this study by executing steady-state flow simulations that raised the water table no higher than the elevation attained in the Central Plateau during the Hanford operational period. This metric was selected because it assumed a maximum remobilization of contaminants that existed under previous fully saturated conditions. Three steady-state flow fields were then used to analyze impacts to transient contaminant transport: a maximum recharge (27,000 acre-ft/yr), a no additional flux (365 acre-ft/yr), and an intermediate recharge case (16,000 acre-ft/yr). The transport behavior of four radionuclides was assessed for a 300 year simula¬tion period with the three flow fields. The four radionuclides are current contaminants of concern (COCs) in the Central Plateau and include tritium, iodine-129, technetium-99, and uranium-238. Transient flow and transport simulations were used to establish hypothetical concentration distributions in the subsurface. Using the simulated concentration distributions in 2005

  5. Use of electrochemical potential noise to detect initiation and propagation of stress corrosion cracks in a 17-4 PH steel

    SciTech Connect

    Gonzalez-Rodriguez, J.G.; Salinas-Bravo, V.M.; Garcia-Ochoa, E.; Diaz-Sanchez, A.

    1997-09-01

    Corrosion potential transients were associated with nucleation and propagation of stress corrosion cracks in a 17-4 precipitation-hardenable (PH) martensitic stainless steel (SS) during slow strain rate tests (SSRT) at 90 C in deaerated sodium chloride (NaCl) solutions, Test solutions included 20 wt% NaCl at pH 3 and 7, similar to normal and faulted steam turbine environments, respectively. Time series were analyzed using the fast Fourier transform method. At the beginning of straining, the consistent noise behavior was perturbed with small potential transients, probably associated with rupture of the surface oxide layer. After yielding, these transients increased in intensity. At maximum load, the transients were still higher in intensity and frequency. These potential transients were related to crack nucleation and propagation. When the steel did not fail by stress corrosion cracking (SCC), such transients were found only at the beginning of the test. The power spectra showed some differences in all cases in roll-off slope and voltage magnitude, but these were not reliable tools to monitor the initiation and propagation of stress corrosion cracks.

  6. Potential Impacts of Leakage from Black Rock Reservoir on the Hanford Site Unconfined Aquifer: Initial Hypothetical Simulations of Flow and Contaminant Transport

    SciTech Connect

    Freedman, Vicky L.

    2008-01-30

    Initial scoping calculations of the unconfined aquifer at the Hanford Site were carried out for the U.S. Bureau of Reclamation (USBR) to investigate the potential impacts on the Hanford unconfined aquifer that would result from leakage from the proposed Black Rock Reservoir to the west. Although impacts on groundwater flow and contaminant transport were quantified based on numerical simulation results, the investigation represented a qualitative assessment of the potential lateral recharge that could result in adverse effects on the aquifer. Because the magnitude of the potential leakage is unknown, hypothetical bounding calculations were performed. When a quantitative analysis of the magnitude of the potential recharge from Black Rock Reservoir is obtained, the hydrologic impacts analysis will be revisited. The analysis presented in this report represents initial bounding calculations. A maximum lateral recharge (i.e., upland flux) was determined in the first part of this study by executing steady-state flow simulations that raised the water table no higher than the elevation attained in the Central Plateau during the Hanford operational period. This metric was selected because it assumed a maximum remobilization of contaminants that existed under previous fully saturated conditions. Three steady-state flow fields were then used to analyze impacts to transient contaminant transport: a maximum recharge (27,000 acre-ft/yr), a no additional flux (365 acre-ft/yr), and an intermediate recharge case (16,000 acre-ft/yr). The transport behavior of four radionuclides was assessed for a 300 year simulation period with the three flow fields. The four radionuclides are tritium, iodine-129, technetium-99, and uranium-238. Transient flow and transport simulations were used to establish hypothetical concentration distributions in the subsurface. Using the simulated concentration distributions in 2005 as initial conditions for steady-state flow runs, simulations were executed to

  7. ZEB2 drives immature T-cell lymphoblastic leukaemia development via enhanced tumour-initiating potential and IL-7 receptor signalling

    PubMed Central

    Goossens, Steven; Radaelli, Enrico; Blanchet, Odile; Durinck, Kaat; Van der Meulen, Joni; Peirs, Sofie; Taghon, Tom; Tremblay, Cedric S.; Costa, Magdaline; Ghahremani, Morvarid Farhang; De Medts, Jelle; Bartunkova, Sonia; Haigh, Katharina; Schwab, Claire; Farla, Natalie; Pieters, Tim; Matthijssens, Filip; Van Roy, Nadine; Best, J. Adam; Deswarte, Kim; Bogaert, Pieter; Carmichael, Catherine; Rickard, Adam; Suryani, Santi; Bracken, Lauryn S.; Alserihi, Raed; Canté-Barrett, Kirsten; Haenebalcke, Lieven; Clappier, Emmanuelle; Rondou, Pieter; Slowicka, Karolina; Huylebroeck, Danny; Goldrath, Ananda W.; Janzen, Viktor; McCormack, Matthew P.; Lock, Richard B.; Curtis, David J.; Harrison, Christine; Berx, Geert; Speleman, Frank; Meijerink, Jules P. P.; Soulier, Jean; Van Vlierberghe, Pieter; Haigh, Jody J.

    2015-01-01

    Early T-cell precursor leukaemia (ETP-ALL) is a high-risk subtype of human leukaemia that is poorly understood at the molecular level. Here we report translocations targeting the zinc finger E-box-binding transcription factor ZEB2 as a recurrent genetic lesion in immature/ETP-ALL. Using a conditional gain-of-function mouse model, we demonstrate that sustained Zeb2 expression initiates T-cell leukaemia. Moreover, Zeb2-driven mouse leukaemia exhibit some features of the human immature/ETP-ALL gene expression signature, as well as an enhanced leukaemia-initiation potential and activated Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signalling through transcriptional activation of IL7R. This study reveals ZEB2 as an oncogene in the biology of immature/ETP-ALL and paves the way towards pre-clinical studies of novel compounds for the treatment of this aggressive subtype of human T-ALL using our Zeb2-driven mouse model. PMID:25565005

  8. ZEB2 drives immature T-cell lymphoblastic leukaemia development via enhanced tumour-initiating potential and IL-7 receptor signalling.

    PubMed

    Goossens, Steven; Radaelli, Enrico; Blanchet, Odile; Durinck, Kaat; Van der Meulen, Joni; Peirs, Sofie; Taghon, Tom; Tremblay, Cedric S; Costa, Magdaline; Farhang Ghahremani, Morvarid; De Medts, Jelle; Bartunkova, Sonia; Haigh, Katharina; Schwab, Claire; Farla, Natalie; Pieters, Tim; Matthijssens, Filip; Van Roy, Nadine; Best, J Adam; Deswarte, Kim; Bogaert, Pieter; Carmichael, Catherine; Rickard, Adam; Suryani, Santi; Bracken, Lauryn S; Alserihi, Raed; Canté-Barrett, Kirsten; Haenebalcke, Lieven; Clappier, Emmanuelle; Rondou, Pieter; Slowicka, Karolina; Huylebroeck, Danny; Goldrath, Ananda W; Janzen, Viktor; McCormack, Matthew P; Lock, Richard B; Curtis, David J; Harrison, Christine; Berx, Geert; Speleman, Frank; Meijerink, Jules P P; Soulier, Jean; Van Vlierberghe, Pieter; Haigh, Jody J

    2015-01-07

    Early T-cell precursor leukaemia (ETP-ALL) is a high-risk subtype of human leukaemia that is poorly understood at the molecular level. Here we report translocations targeting the zinc finger E-box-binding transcription factor ZEB2 as a recurrent genetic lesion in immature/ETP-ALL. Using a conditional gain-of-function mouse model, we demonstrate that sustained Zeb2 expression initiates T-cell leukaemia. Moreover, Zeb2-driven mouse leukaemia exhibit some features of the human immature/ETP-ALL gene expression signature, as well as an enhanced leukaemia-initiation potential and activated Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signalling through transcriptional activation of IL7R. This study reveals ZEB2 as an oncogene in the biology of immature/ETP-ALL and paves the way towards pre-clinical studies of novel compounds for the treatment of this aggressive subtype of human T-ALL using our Zeb2-driven mouse model.

  9. Supplemental irrigation as an initiative to support water and food security: A global evaluation of the potential to support and increase precipitation-fed wheat production

    NASA Astrophysics Data System (ADS)

    Smilovic, M.; Gleeson, T. P.; Adamowski, J. F.; Langhorn, C.; Kienzle, S. W.

    2016-12-01

    Supplemental irrigation is the practice of supporting precipitation-fed agriculture with limited irrigation. Precipitation-fed agriculture dominates the agricultural landscape, but is vulnerable to intraseasonal and interannual variability in precipitation and climate. The interplay between food security, water resources, ecosystem health, energy, and livelihoods necessitates evaluating and integrating initiatives that increase agricultural production while reducing demands on water resources. Supplemental irrigation is the practice of minimally irrigating in an effort to stabilize and increase agricultural production, as well as increase water productivity - the amount of crop produced per unit of water. The potential of supplemental irrigation to support both water and food security has yet to be evaluated at regional and global scales. We evaluate whether supplemental irrigation could stabilize and increase agricultural production of wheat by determining locally-calibrated water use-crop yield relationships, known as crop-water production functions. Crop-water production functions are functions of seasonal water use and crop yield, and previous efforts have largely ignored the effects of the temporal distribution of water use throughout the growing season. We significantly improve upon these efforts and provide an opportunity to evaluate supplemental irrigation that appropriately acknowledges the effects of irrigation scheduling. Integrating agroclimatic and crop data with the crop-water model Aquacrop, we determine the increases in wheat production achieved by maximizing water productivity, sharing limited water between different years, and other irrigation scenarios. The methodology presented and evaluation of supplemental irrigation provides water mangers, policy makers, governments, and non-governmental organizations the tools to appropriately understand and determine the potential of this initiative to support precipitation-fed agriculture.

  10. Movement related cortical potentials of cued versus self-initiated movements: double dissociated modulation by dorsal premotor cortex versus supplementary motor area rTMS.

    PubMed

    Lu, Ming-Kuei; Arai, Noritoshi; Tsai, Chon-Haw; Ziemann, Ulf

    2012-04-01

    The dorsal premotor cortex (PMd) is thought to play a significant role in movement preparation cued by sensory information rather than in self-initiated movements. The evidence in humans for this contention is still circumstantial. Here we explored the effects of modulation of PMd by excitability decreasing 1 Hz repetitive transcranial magnetic stimulation (rTMS) versus excitability increasing 5 Hz rTMS on two forms of movement related cortical potentials: contingent negative variation (CNV) versus Bereitschaftspotential (BP) reflecting externally cued versus self-triggered movement preparation. Ten healthy right-handed subjects performed visually cued or self-triggered simple sequential finger movements with their right hand. CNV and BP were recorded by 25 EEG electrodes covering the fronto-centro-parietal cortex and divided into an early (1500-500 ms before a go-signal or movement onset) and a late potential (500-0 ms). MRI-navigated 1 Hz rTMS of the left PMd resulted in significant increase of the late CNV over the left central region predominantly contralateral to the prepared right hand movement, while 5 Hz rTMS had no effect on CNV. In contrast, 1 and 5 Hz rTMS did not modify BP. Control experiments of 1 Hz rTMS of the supplementary motor area (SMA) and of low-intensity 1 Hz rTMS of the left primary motor cortex did not change CNV, but 1 Hz SMA-rTMS increased late BP. This double dissociation of effects of PMd-rTMS versus SMA-rTMS on CNV versus BP provides direct evidence that the left PMd in humans is more involved in preparatory processes of externally cued rather than self-initiated movements, contrasting with an opposite role of the SMA. Copyright © 2011 Wiley Periodicals, Inc.

  11. Transformation assay in Bhas 42 cells: a model using initiated cells to study mechanisms of carcinogenesis and predict carcinogenic potential of chemicals.

    PubMed

    Sasaki, Kiyoshi; Umeda, Makoto; Sakai, Ayako; Yamazaki, Shojiro; Tanaka, Noriho

    2015-01-01

    Transformation assays using cultured cells have been applied to the study of carcinogenesis. Although various cell systems exist, few cell types such as BALB/c 3T3 subclones and Syrian hamster embryo cells have been used to study chemically induced two-stage carcinogenesis. Bhas 42 cells were established as a clone by the transfection with the v-Ha-ras gene into mouse BALB/c 3T3 A31-1-1 cells and their subsequent selection based on their sensitivity to 12-O-tetradecanoylphorbol-13-acetate. Using Bhas 42 cells, transformed foci were induced by the treatment with nongenotoxic carcinogens, most of which act as tumor promoters. Therefore, Bhas 42 cells were considered to be a model of initiated cells. Subsequently, not only nongenotoxic carcinogens but also genotoxic carcinogens, most of which act as tumor initiators, were found to induce transformed foci by the modification of the protocol. Furthermore, transformation of Bhas 42 cells was induced by the transfection with genes of oncogenic potential. We interpret this high sensitivity of Bhas 42 cells to various types of carcinogenic stimuli to be related to the multistage model of carcinogenesis, as the transfection of v-Ha-ras gene further advances the parental BALB/c 3T3 A31-1-1 cells toward higher transforming potential. Thus, we propose that Bhas 42 cells are a novel and sensitive cell line for the analysis of carcinogenesis and can be used for the detection of not only carcinogenic substances but also gene alterations related to oncogenesis. This review will address characteristics of Bhas 42 cells, the transformation assay protocol, validation studies, and the various chemicals tested in this assay.

  12. Milnacipran treatment and potential biomarkers in depressed patients following an initial SSRI treatment failure: a prospective, open-label, 24-week study.

    PubMed

    Hashimoto, Tasuku; Sakurai, Daiji; Oda, Yasunori; Hasegawa, Tadashi; Kanahara, Nobuhisa; Sasaki, Tsuyoshi; Komatsu, Hideki; Takahashi, Junpei; Oiwa, Takahiro; Sekine, Yoshimoto; Watanabe, Hiroyuki; Iyo, Masaomi

    2015-01-01

    We assessed the effect of switching patients with major depressive disorder to milnacipran following an initial selective serotonin reuptake inhibitor treatment failure, and explored potential biomarkers in their blood. We conducted a prospective, open-label, 24-week trial. Depression was assessed with the 17-item Hamilton Depression Rating Scale. Patients showing a ≥50% reduction in Hamilton Depression Rating Scale scores from baseline to final visit were considered responders. Regarding adverse effects (AEs), moderate-to-severe AEs were specifically identified as effects that required any medical treatment or that induced treatment withdrawals. We also measured blood levels of various molecules including inflammatory cytokines. Of the 30 participants who enrolled, 17 completed this study. The responder rate was 30% (n=10). Baseline serum levels of interleukin-6 (Z=-2.155; P=0.031) and interleukin-8 (Z=-2.616; P=0.009) were significantly higher when moderate-to-severe AEs were present (n=13 patients with moderate-to-severe AEs). Serum levels of macrophage inflammatory protein-1β showed a significant continuous decrease from the baseline level (Friedman's test: χ (2)=23.9, df=4, P<0.001) only in non-responders. These results demonstrate that serum levels of interleukin-6, interleukin-8, and macrophage inflammatory protein-1β as potential blood biomarkers could be utilized to identify the responsiveness of patients to serotonin and norepinephrine reuptake inhibitor like milnacipran, or to identify those patients who may experience AEs strong enough to warrant discontinuation of treatment.

  13. A Ternary Brain-Computer Interface Based on Single-Trial Readiness Potentials of Self-initiated Fine Movements: A Diversified Classification Scheme

    PubMed Central

    Abou Zeid, Elias; Rezazadeh Sereshkeh, Alborz; Schultz, Benjamin; Chau, Tom

    2017-01-01

    In recent years, the readiness potential (RP), a type of pre-movement neural activity, has been investigated for asynchronous electroencephalogram (EEG)-based brain-computer interfaces (BCIs). Since the RP is attenuated for involuntary movements, a BCI driven by RP alone could facilitate intentional control amid a plethora of unintentional movements. Previous studies have mainly attempted binary single-trial classification of RP. An RP-based BCI with three or more states would expand the options for functional control. Here, we propose a ternary BCI based on single-trial RPs. This BCI classifies amongst an idle state, a left hand and a right hand self-initiated fine movement. A pipeline of spatio-temporal filtering with per participant parameter optimization was used for feature extraction. The ternary classification was decomposed into binary classifications using a decision-directed acyclic graph (DDAG). For each class pair in the DDAG structure, an ordered diversified classifier system (ODCS-DDAG) was used to select the best among various classification algorithms or to combine the results of different classification algorithms. Using EEG data from 14 participants performing self-initiated left or right key presses, punctuated with rest periods, we compared the performance of ODCS-DDAG to a ternary classifier and four popular multiclass decomposition methods using only a single classification algorithm. ODCS-DDAG had the highest performance (0.769 Cohen's Kappa score) and was significantly better than the ternary classifier and two of the four multiclass decomposition methods. Our work supports further study of RP-based BCI for intuitive asynchronous environmental control or augmentative communication. PMID:28596725

  14. Photo-initiated thiol-ene click reactions as a potential strategy for incorporation of [M(I)(CO)3]+ (M = Re, (99m)Tc) complexes.

    PubMed

    Hayes, Thomas R; Lyon, Patrice A; Silva-Lopez, Elsa; Twamley, Brendan; Benny, Paul D

    2013-03-18

    Click reactions offer a rapid technique to covalently assemble two molecules. In radiopharmaceutical construction, these reactions can be utilized to combine a radioactive metal complex with a biological targeting molecule to yield a potent tool for imaging or therapy applications. The photo-initiated radical thiol-ene click reaction between a thiol and an alkene was examined for the incorporation of [M(I)(CO)3](+) (M = Re, (99m)Tc) systems for conjugating biologically active targeting molecules containing a thiol. In this strategy, a potent chelate system, 2,2'-dipicolylamine (DPA), for [M(I)(CO)3](+) was functionalized at the central amine with a terminal alkene linker that was explored with two synthetic approaches, click then chelate and chelate then click, to determine the flexibility and applicability of the thiol-ene click reaction to specifically incorporate ligand systems and metal complexes with a thiol containing molecule. In the click then chelate approach, the thiol-ene click reaction was carried out with the DPA chelate followed by complexation with [M(I)(CO)3](+). In the chelate then click approach, the alkene functionalized DPA chelate was first complexed with [M(I)(CO)3](+) followed by the conduction of the thiol-ene click reaction. Initial studies utilized benzyl mercaptan as a model thiol for both strategies to generate the identical product from either route to provide information on reactivity and product formation. DPA ligands functionalized with two unique linker systems (allyl and propyl allyl ether) were prepared to examine the effect of the proximity of the chelate or complex on the thiol-ene click reaction. Both the thiol-ene click and coordination reactions with Re, (99m)Tc were performed in moderate to high yields demonstrating the potential of the thiol-ene click reaction for [M(I)(CO)3](+) incorporation into thiol containing biomolecules.

  15. Milnacipran treatment and potential biomarkers in depressed patients following an initial SSRI treatment failure: a prospective, open-label, 24-week study

    PubMed Central

    Hashimoto, Tasuku; Sakurai, Daiji; Oda, Yasunori; Hasegawa, Tadashi; Kanahara, Nobuhisa; Sasaki, Tsuyoshi; Komatsu, Hideki; Takahashi, Junpei; Oiwa, Takahiro; Sekine, Yoshimoto; Watanabe, Hiroyuki; Iyo, Masaomi

    2015-01-01

    Background We assessed the effect of switching patients with major depressive disorder to milnacipran following an initial selective serotonin reuptake inhibitor treatment failure, and explored potential biomarkers in their blood. Methods We conducted a prospective, open-label, 24-week trial. Depression was assessed with the 17-item Hamilton Depression Rating Scale. Patients showing a ≥50% reduction in Hamilton Depression Rating Scale scores from baseline to final visit were considered responders. Regarding adverse effects (AEs), moderate-to-severe AEs were specifically identified as effects that required any medical treatment or that induced treatment withdrawals. We also measured blood levels of various molecules including inflammatory cytokines. Results Of the 30 participants who enrolled, 17 completed this study. The responder rate was 30% (n=10). Baseline serum levels of interleukin-6 (Z=−2.155; P=0.031) and interleukin-8 (Z=−2.616; P=0.009) were significantly higher when moderate-to-severe AEs were present (n=13 patients with moderate-to-severe AEs). Serum levels of macrophage inflammatory protein-1β showed a significant continuous decrease from the baseline level (Friedman’s test: χ2=23.9, df=4, P<0.001) only in non-responders. Conclusion These results demonstrate that serum levels of interleukin-6, interleukin-8, and macrophage inflammatory protein-1β as potential blood biomarkers could be utilized to identify the responsiveness of patients to serotonin and norepinephrine reuptake inhibitor like milnacipran, or to identify those patients who may experience AEs strong enough to warrant discontinuation of treatment. PMID:26677330

  16. A pipeline of spatio-temporal filtering for predicting the laterality of self-initiated fine movements from single trial readiness potentials

    NASA Astrophysics Data System (ADS)

    Abou Zeid, Elias; Rezazadeh Sereshkeh, Alborz; Chau, Tom

    2016-12-01

    Objective. In recent years, the readiness potential (RP), a type of pre-movement neural activity, has been investigated for asynchronous electroencephalogram (EEG)-based brain-computer interfaces (BCIs). Since the RP is attenuated for involuntary movements, a BCI driven by RP alone could facilitate intentional control amid a plethora of unintentional movements. Previous studies have attempted single trial classification of RP via spatial and temporal filtering methods, or by combining the RP with event-related desynchronization. However, RP feature extraction remains challenging due to the slow non-oscillatory nature of the potential, its variability among participants and the inherent noise in EEG signals. Here, we propose a participant-specific, individually optimized pipeline of spatio-temporal filtering (PSTF) to improve RP feature extraction for laterality prediction. Approach. PSTF applies band-pass filtering on RP signals, followed by Fisher criterion spatial filtering to maximize class separation, and finally temporal window averaging for feature dimension reduction. Optimal parameters are simultaneously found by cross-validation for each participant. Using EEG data from 14 participants performing self-initiated left or right key presses as well as two benchmark BCI datasets, we compared the performance of PSTF to two popular methods: common spatial subspace decomposition, and adaptive spatio-temporal filtering. Main results. On the BCI benchmark data sets, PSTF performed comparably to both existing methods. With the key press EEG data, PSTF extracted more discriminative features, thereby leading to more accurate (74.99% average accuracy) predictions of RP laterality than that achievable with existing methods. Significance. Naturalistic and volitional interaction with the world is an important capacity that is lost with traditional system-paced BCIs. We demonstrated a significant improvement in fine movement laterality prediction from RP features alone. Our

  17. A pipeline of spatio-temporal filtering for predicting the laterality of self-initiated fine movements from single trial readiness potentials.

    PubMed

    Zeid, Elias Abou; Sereshkeh, Alborz Rezazadeh; Chau, Tom

    2016-12-01

    In recent years, the readiness potential (RP), a type of pre-movement neural activity, has been investigated for asynchronous electroencephalogram (EEG)-based brain-computer interfaces (BCIs). Since the RP is attenuated for involuntary movements, a BCI driven by RP alone could facilitate intentional control amid a plethora of unintentional movements. Previous studies have attempted single trial classification of RP via spatial and temporal filtering methods, or by combining the RP with event-related desynchronization. However, RP feature extraction remains challenging due to the slow non-oscillatory nature of the potential, its variability among participants and the inherent noise in EEG signals. Here, we propose a participant-specific, individually optimized pipeline of spatio-temporal filtering (PSTF) to improve RP feature extraction for laterality prediction. PSTF applies band-pass filtering on RP signals, followed by Fisher criterion spatial filtering to maximize class separation, and finally temporal window averaging for feature dimension reduction. Optimal parameters are simultaneously found by cross-validation for each participant. Using EEG data from 14 participants performing self-initiated left or right key presses as well as two benchmark BCI datasets, we compared the performance of PSTF to two popular methods: common spatial subspace decomposition, and adaptive spatio-temporal filtering. On the BCI benchmark data sets, PSTF performed comparably to both existing methods. With the key press EEG data, PSTF extracted more discriminative features, thereby leading to more accurate (74.99% average accuracy) predictions of RP laterality than that achievable with existing methods. Naturalistic and volitional interaction with the world is an important capacity that is lost with traditional system-paced BCIs. We demonstrated a significant improvement in fine movement laterality prediction from RP features alone. Our work supports further study of RP-based BCI for

  18. Infection with Theiler's murine encephalomyelitis virus directly induces proinflammatory cytokines in primary astrocytes via NF-kappaB activation: potential role for the initiation of demyelinating disease.

    PubMed

    Palma, JoAnn P; Kwon, Daeho; Clipstone, Neil A; Kim, Byung S

    2003-06-01

    Theiler's virus infection in the central nervous system (CNS) induces a demyelinating disease very similar to human multiple sclerosis. We have assessed cytokine gene activation upon Theiler's murine encephalomyelitis virus (TMEV) infection and potential mechanisms in order to delineate the early events in viral infection that lead to immune-mediated demyelinating disease. Infection of SJL/J primary astrocyte cultures induces selective proinflammatory cytokine genes (interleukin-12p40 [IL-12p40], IL-1, IL-6, tumor necrosis factor alpha, and beta interferon [IFN-beta]) important in the innate immune response to infection. We find that TMEV-induced cytokine gene expression is mediated by the NF-kappaB pathway based on the early nuclear NF-kappaB translocation and suppression of cytokine activation in the presence of specific inhibitors of the NF-kappaB pathway. Further studies show this to be partly independent of dsRNA-dependent protein kinase (PKR) and IFN-alpha/beta pathways. Altogether, these results demonstrate that infection of astrocytes and other CNS-resident cells by TMEV provides the early NF-kappaB-mediated signals that directly activate various proinflammatory cytokine genes involved in the initiation and amplification of inflammatory responses in the CNS known to be critical for the development of immune-mediated demyelination.

  19. Potential Nonresponse Bias in a Clinical Examination After Initial Screening Using Iron Phenotyping and HFE Genotyping in the Hemochromatosis and Iron Overload Screening Study

    PubMed Central

    Barton, James C.; Passmore, Leah; Harrison, Helen; Reboussin, David M.; Harris, Emily L.; Rivers, Charles A.; Fadojutimi-Akinsiku, Margaret; Wenzel, Lari; Diaz, Sharmin

    2009-01-01

    Background: Little is known about the factors affecting participation in clinical assessments after HEmochromatosis and IRon Overload Screening. Methods: Initial screening of 101,168 primary care patients in the HEmochromatosis and IRon Overload Screening study was performed using serum iron measures and hemochromatosis gene (HFE) genotyping. Using iron phenotypes and HFE genotypes, we identified 2256 cases and 1232 controls eligible to participate in a clinical examination. To assess the potential for nonresponse bias, we compared the sociodemographic, health status, and attitudinal characteristics of participants and nonparticipants using adjusted odds ratios (ORs) and 95% confidence interval (CI). Results: Overall participation was 74% in cases and 52% in controls; in both groups, participation was highest at a health maintenance organization and lowest among those under 45 years of age (cases: OR = 0.68; 95% CI 0.53, 0.87; controls: OR = 0.59; 95% CI 0.44, 0.78). In controls only, participation was also lower among those over 65 years of age than the reference group aged 46–64 (OR = 0.64; 95% CI 0.47, 0.88). Among cases, participation was higher in HFE C282Y homozygotes (OR = 3.98; 95% CI 2.60, 6.09), H63D homozygotes (OR = 2.79; 95% CI 1.23, 6.32), and C282Y/H63D compound heterozygotes (OR = 1.82; 95% CI 1.03, 3.22) than in other genotypes, and lower among non-Caucasians and those who preferred a non-English language than in Caucasians and those who preferred English (p < 0.0001). Conclusions: Subjects with greatest risk to have iron overload (C282Y homozygotes; cases ≥45 years; Caucasians) were more likely to participate in a postscreening clinical examination than other subjects. We detected no evidence of strong selection bias. PMID:19860558

  20. Western Kentucky University Research Foundation Biodiesel Project

    SciTech Connect

    Pan, Wei-Ping; Cao, Yan

    2013-03-15

    fermented to create ethanol. In the United States almost all starch ethanol is mainly manufactured from corn grains. The technology for manufacturing corn ethanol can be considered mature as of the late 1980s. In 2005, 14.3 % of the U.S. corn harvest was processed to produce 1.48 x10{sup 10} liters of ethanol, energetically equivalent to 1.72 % of U.S. gasoline usage. Soybean oil is extracted from 1.5 % of the U.S. soybean harvest to produce 2.56 x 10{sup 8} liters of bio-diesel, which was 0.09 % of U.S. diesel usage. However, reaching maximum rates of bio-fuel supply from corn and soybeans is unlikely because these crops are presently major contributors to human food supplies through livestock feed and direct consumption. Moreover, there currently arguments on that the conversion of many types of many natural landscapes to grow corn for feedstock is likely to create substantial carbon emissions that will exacerbate globe warming. On the other hand, there is a large underutilized resource of cellulose biomass from trees, grasses, and nonedible parts of crops that could serve as a feedstock. One of the potentially significant new bio-fuels is so called "cellulosic ethanol", which is dependent on break-down by microbes or enzymes. Because of technological limitations (the wider variety of molecular structures in cellulose and hemicellulose requires a wider variety of microorganisms to break them down) and other cost hurdles (such as lower kinetics), cellulosic ethanol can currently remain in lab scales. Considering farm yields, commodity and fuel prices, farm energy and agrichemical inputs, production plant efficiencies, byproduct production, greenhouse gas (GHG) emissions, and other environmental effects, a life-cycle evaluation of competitive indicated that corn ethanol yields 25 % more energy than the energy invested in its production, whereas soybean bio-diesel yields 93 % more. Relative to the fossil fuels they displace, greenhouse gas emissions are reduced 12 % by the

  1. Rates of upgrade of ICD recipients to CRT in clinical practice and the potential impact of the more liberal use of CRT at initial implant.

    PubMed

    Scott, Paul A; Whittaker, Andrew; Zeb, Mehmood; Watts, Edd; Yue, Arthur M; Roberts, Paul R; Morgan, John M

    2012-01-01

    Many implantable cardioverter defibrillator (ICD) recipients may develop indications for cardiac resynchronization therapy (CRT) during follow-up. However, the actual upgrade rate during follow-up in clinical practice is not known. We performed a single center retrospective observational study of all new ICD implants over 5 years (2003-2007). The rate of CRT upgrade of patients initially implanted with a single-/dual-chamber ICD during follow-up was assessed. The impact of using alternative criteria on the need for CRT in ICD recipients at initial implant was also evaluated. During the study period, there were 549 new ICD implants. The initial implant was a single/dual-chamber ICD in 73% (n = 399) and a CRT-D in 27% (n = 150). During follow-up (48±20 months) of the 399 ICD recipients, 70 (17.5%) died and 15 (3.8%) were upgraded to CRT, including eight cases where left ventricular lead implant had been initially unsuccessful. Upgrade rates at 1, 3, and 5 years were 0.03%, 2.4%, and 5.1%, respectively. Using alternative CRT criteria (left ventricular ejection fraction [LVEF]≤30%, QRS ≥130 ms, New York Heart Association I-IV) 42.6% (n = 234) of ICD recipients met criteria for CRT at initial implant. In this retrospective single center study, rates of CRT upgrade in ICD recipients over the medium term were low, which may reflect underuse in otherwise appropriate candidates. The more liberal use of CRT at initial implant in patients with a reduced LVEF, a broad QRS, but only mild heart failure symptoms would require approximately 50% increase in CRT use in ICD recipients at initial implant, and may help address some of the suggested underutilization. ©2011, The Authors. Journal compilation ©2011 Wiley Periodicals, Inc.

  2. Tumor-derived mesenchymal stem cells and orthotopic site increase the tumor initiation potential of putative mouse mammary cancer stem cells derived from MMTV-PyMT mice.

    PubMed

    Lanza, Denise Grant; Ma, Jun; Guest, Ian; Uk-Lim, Chang; Glinskii, Anna; Glinsky, Gennadi; Sell, Stewart

    2012-12-01

    The ability to transplant mammary cancer stem cells, identified by the phenotype CD24(+)CD29(+)CD49f(+)Sca-1(low), is dependent on the microenvironment in which the cells are placed. Using the MMTV-PyMT mouse model of mammary cancer, we now report two methods of tumor growth enhancement: contributions of tumor stroma in the form of tumor-derived mesenchymal stem cells and orthotopic vs. heterotopic transplantation sites. To support evidence of stem cell function, tumor-derived mesenchymal stem cells differentiated into adipocyte- and osteocyte-like cells after culture in specific medium. Co-injection of tumor-initiating cells with tumor-derived mesenchymal stem cells significantly increased tumor initiation compared to subcutaneous injection of TICs alone; co-injection also allowed tumor initiation with a single TIC. Interestingly, we observed the formation of sarcomas after co-injections of tumor-derived mesenchymal stem cells or mouse embryonic fibroblasts with TICs; sarcomas are not observed in spontaneous MMTV-PyMT tumors and rarely observed in injections of TICs alone. Tumor initiation was also significantly increased in the orthotopic injection site compared to heterotopic injections. We conclude that tumor stroma and orthotopic sites both enhance tumor initiation by mammary cancer stem cells.

  3. The Cucumber Genome Initiative-An International Effort to Unlock the Genetic Potential of an Orphan Crop Using Novel Genomic Technology

    USDA-ARS?s Scientific Manuscript database

    Cucumber is an important vegetable in the world. However, its narrow genetic basis makes it a less desirable species for genetic study and molecular breeding. The Cucumber Genome Initiative (CuGI) was established with aims: 1) to obtain a complete sequence of the genome; 2) to get an in-depth und...

  4. Durability of initial antiretroviral therapy in a resource-constrained setting and the potential need for zidovudine weight-based dosing.

    PubMed

    Willig, James H; Echevarria, Juan; Westfall, Andrew O; Iglesias, David; Henostroza, German; Seas, Carlos; Mugavero, Michael J; Allison, Jeroan; Paz, Jorge; Hernandez, Fiorella; Tomatis, Cristina; Saag, Michael S; Gotuzzo, Eduardo

    2010-02-01

    Whereas access to antiretroviral therapy (ART) for HIV-infected individuals in the developing world is increasing, data on factors impacting initial regimen durability are lacking. Retrospective review patients starting initial ART at Instituto de Medicine Tropical (Lima, Peru) April 1, 2004 to December 30, 2007. Survival methods (Kaplan-Meier, Cox proportional hazard) assessed factors associated with regimen durability including an interaction term between nucleoside reverse transcriptase inhibitor backbone and time. Decreased initial regimen durability was observed with weight <60 kg [hazards ratio (HR) = 1.77; 95% confidence interval (CI) = 1.25-2.51], CD4 <200 (HR = 1.73; 95% CI = 1.03-2.91), and zidovudine (AZT) use at <120 days (HR = 2.09; 95% CI = 1.22-3.57). In contrast, after 120 days, AZT use decreased risk of discontinuation (HR = 0.52; 95% CI = 0.28-0.95). Early (<120 days) toxicity-related discontinuation of AZT containing regimens was observed in 44% of patients <50 kg at baseline vs. 14% of those >70 kg. An increased risk of early toxicity-related discontinuation of AZT-containing regimens was observed for baseline weight <60 kg (HR = 2.52; 95% CI = 1.46-4.35). Lower baseline weight and lower CD4 values at ART initiation were associated with decreased regimen durability. Compared with didanosine/stavudine, AZT use initially increased, then subsequently (>120 days) lowered hazards for regimen discontinuation. Weight <60 kg was associated with an increased risk of toxicity-related AZT discontinuation. As ART use expands globally, further study into maximally durable, least toxic regimens, and the role of weight-based AZT dosing is imperative.

  5. Real-world application of breast-specific gamma imaging, initial experience at a community breast center and its potential impact on clinical care.

    PubMed

    Zhou, Minhao; Johnson, Nathalie; Blanchard, Deb; Bryn, Sally; Nelson, Joanne

    2008-05-01

    Breast-specific gamma imaging (BSGI) has brought scintimammography back to the forefront by using a dedicated small field-of-view system designed to detect and localize lesions down to 2 mm. Initial studies have reported sensitivity equaling that of magnetic resonance imaging, but with improved specificity. We reviewed our initial experience to evaluate the impact of this technology at our community breast center. We performed a retrospective review of the initial 176 patients who underwent BSGI. A total of 128 patients underwent BSGI because of suspicious imaging, abnormal physical examination, or high risk with dense breasts. BSGI was positive in 12 of 107 patients with breast imaging reporting and data system (BI-RADS) 1, 2, or 3. Two of these were cancer. Of the 21 patients with BI-RADS 4, 18 were BSGI negative (11 with benign biopsy, 7 observed), and 3 were BSGI positive with 2 being cancer. Forty-eight patients with a new diagnosis of cancer obtained BSGI for further work-up. It was positive at a new location in 6 cases: 2 cases were new cancers in the contralateral breast, 1 was in the ipsilateral breast, and the remaining 3 had benign pathology. Of the 176 initial patients, clinical management was changed significantly in 14.2%, with another 6.3% in whom a negative BSGI could have prevented a biopsy. BSGI has played an important role in our clinical management of breast patients with complex breast tissue. BSGI is also a good adjunctive imaging tool in the work-up of newly diagnosed breast cancer patients.

  6. Microdrill Initiative - Initial Market Evaluation

    SciTech Connect

    Spears & Associates, Inc

    2003-07-01

    The U.S. Department of Energy (DOE) is launching a major research and development initiative to create a small, fast, inexpensive and environmentally friendly rig for drilling 5000 feet boreholes to investigate potential oil and gas reservoirs. DOE wishes to get input from petroleum industry operators, service companies and equipment suppliers on the operation and application of this coiled-tubing-based drilling unit. To that end, DOE has asked Spears & Associates, Inc. (SAI) to prepare a special state-of-the-market report and assist during a DOE-sponsored project-scoping workshop in Albuquerque near the end of April 2003. The scope of the project is four-fold: (1) Evaluate the history, status and future of demand for very small bore-hole drilling; (2) Measure the market for coiled tubing drilling and describe the state-of-the-art; (3) Identify companies and individuals who should have an interest in micro drilling and invite them to the DOE workshop; and (4) Participate in 3 concurrent workshop sessions, record and evaluate participant comments and report workshop conclusions.

  7. Assessing potentially time-dependent treatment effect from clinical trials and observational studies for survival data, with applications to the Women's Health Initiative combined hormone therapy trial.

    PubMed

    Yang, Song; Prentice, Ross L

    2015-05-20

    For risk and benefit assessment in clinical trials and observational studies with time-to-event data, the Cox model has usually been the model of choice. When the hazards are possibly non-proportional, a piece-wise Cox model over a partition of the time axis may be considered. Here, we propose to analyze clinical trials or observational studies with time-to-event data using a certain semiparametric model. The model allows for a time-dependent treatment effect. It includes the important proportional hazards model as a sub-model and can accommodate various patterns of time-dependence of the hazard ratio. After estimation of the model parameters using a pseudo-likelihood approach, simultaneous confidence intervals for the hazard ratio function are established using a Monte Carlo method to assess the time-varying pattern of the treatment effect. To assess the overall treatment effect, estimated average hazard ratio and its confidence intervals are also obtained. The proposed methods are applied to data from the Women's Health Initiative. To compare the Women's Health Initiative clinical trial and observational study, we use the propensity score in building the regression model. Compared with the piece-wise Cox model, the proposed model yields a better model fit and does not require partitioning of the time axis. Copyright © 2015 John Wiley & Sons, Ltd.

  8. Generation of a Realistic Soil Moisture Initialization System and its Potential Impact on Short-to-Seasonal Forecasting of Near Surface Variables

    NASA Astrophysics Data System (ADS)

    Boisserie, M.; Cocke, S.; O'Brien, J. J.

    2009-12-01

    Although the amount of water contained in the soil seems insignificant when compared to the total amount of water on a global-scale, soil moisture is widely recognized as a crucial variable for climate studies. It plays a key role in regulating the interaction between the atmosphere and the land-surface by controlling the repartition between the surface latent and sensible heat fluxes. In addition, the persistence of soil moisture anomalies provides one of the most important components of memory for the climate system. Several studies have shown that, during the boreal summer in mid-latitudes, the soil moisture role in controlling the continental precipitation variability may be more important than that of the sea surface temperature (Koster et al. 2000, Hong and Kalnay 2000, Koster et al. 2000, Kumar and Hoerling 1995, Trenberth et al. 1998, Shukla 1998). Although all of the above studies have demonstrated the strong sensitivity of seasonal forecasts to the soil moisture initial conditions, they relied on extreme or idealized soil moisture levels. The question of whether realistic soil moisture initial conditions lead to improved seasonal predictions has not been adequately addressed. Progress in addressing this question has been hampered by the lack of long-term reliable observation-based global soil moisture data sets. Since precipitation strongly affects the soil moisture characteristics at the surface and in depth, an alternative to this issue is to assimilate precipitation. Because precipitation is a diagnostic variable, most of the current reanalyses do not directly assimilate it into their models (M. Bosilovitch, 2008). In this study, an effective technique that directly assimilates the precipitation is used. We examine two experiments. In the first experiment, the model is initialized by directly assimilating a global, 3-hourly, 1.0° precipitation dataset, provided by Sheffield et al. (2006), in a continuous assimilation period of a couple of months. For

  9. Activity spaces of men who have sex with men: An initial exploration of geographic variation in locations of routine, potential sexual risk, and prevention behaviors.

    PubMed

    Vaughan, Adam S; Kramer, Michael R; Cooper, Hannah L F; Rosenberg, Eli S; Sullivan, Patrick S

    2017-02-01

    Theory and research on HIV and among men who have sex with men (MSM) have long suggested the importance of non-residential locations in defining structural exposures. Despite this, most studies within these fields define place as a residential context, neglecting the potential influence of non-residential locations on HIV-related outcomes. The concept of activity spaces, defined as a set of locations to which an individual is routinely exposed, represents one theoretical basis for addressing this potential imbalance. Using a one-time online survey to collect demographic, behavioral, and spatial data from MSM, this paper describes activity spaces and examines correlates of this spatial variation. We used latent class analysis to identify categories of activity spaces using spatial data on home, routine, potential sexual risk, and HIV prevention locations. We then assessed individual and area-level covariates for their associations with these categories. Classes were distinguished by the degree of spatial variation in routine and prevention behaviors (which were the same within each class) and in sexual risk behaviors (i.e., sex locations and locations of meeting sex partners). Partner type (e.g. casual or main) represented a key correlate of the activity space. In this early examination of activity spaces in an online sample of MSM, patterns of spatial behavior represent further evidence of significant spatial variation in locations of routine, potential HIV sexual risk, and HIV prevention behaviors among MSM. Although prevention behaviors tend to have similar geographic variation as routine behaviors, locations where men engage in potentially high-risk behaviors may be more spatially focused for some MSM than for others.

  10. Potential use of biomarkers in acute kidney injury: report and summary of recommendations from the 10th Acute Dialysis Quality Initiative consensus conference.

    PubMed

    Murray, Patrick T; Mehta, Ravindra L; Shaw, Andrew; Ronco, Claudio; Endre, Zoltan; Kellum, John A; Chawla, Lakhmir S; Cruz, Dinna; Ince, Can; Okusa, Mark D

    2014-03-01

    Over the last decade there has been considerable progress in the discovery and development of biomarkers of kidney disease, and several have now been evaluated in different clinical settings. Although there is a growing literature on the performance of various biomarkers in clinical studies, there is limited information on how these biomarkers would be utilized by clinicians to manage patients with acute kidney injury (AKI). Recognizing this gap in knowledge, we convened the 10th Acute Dialysis Quality Initiative meeting to review the literature on biomarkers in AKI and their application in clinical practice. We asked an international group of experts to assess four broad areas for biomarker utilization for AKI: risk assessment, diagnosis, and staging; differential diagnosis; prognosis and management; and novel physiological techniques including imaging. This article provides a summary of the key findings and recommendations of the group, to equip clinicians to effectively use biomarkers in AKI.

  11. A review of candidate multilayer insulation systems for potential use on wet-launched LH2 tankage for the Space Exploration Initiative lunar missions

    NASA Technical Reports Server (NTRS)

    Knoll, Richard H.; Stochl, Robert J.; Sanabria, Rafael

    1991-01-01

    The storage of cryogenic propellants such as liquid hydrogen (LH2) and liquid oxygen (LO2) for the future Space Exploration Initiative (SEI) will require lightweight, high performance thermal protection systems (TPSs). For the near-term lunar missions, the major weight element for most of the TPSs will be multilayer insulation (MLI) and/or the special structures/systems required to accommodate the MLI. Methods of applying MLI to LH2 tankage to avoid condensation or freezing of condensible gases such as nitrogen or oxygen while in the atmosphere are discussed. Because relatively thick layers of MLI will be required for storage times of a month or more, the transient performance from ground-hold to space-hold of the systems will become important in optimizing the TPSs for many of the missions. The ground-hold performance of several candidate systems are given as well as a qualitative assessment of the transient performance effects.

  12. A review of candidate multilayer insulation systems for potential use on wet-launched LH2 tankage for the space exploration initiative lunar missions

    NASA Technical Reports Server (NTRS)

    Knoll, Richard H.; Stochl, Robert J.; Sanabria, Rafael

    1991-01-01

    The storage of cryogenic propellants such as liquid hydrogen (LH2) and liquid oxygen (LO2) for the future Space Exploration Initiative (SEI) will require lightweight, high performance thermal protection systems (TPS's). For the near-term lunar missions, the major weight element for most of the TPS's will be multilayer insulation (MLI) and/or the special structures/systems required to accommodate the MLI. Methods of applying MLI to LH2 tankage to avoid condensation or freezing of condensible gases such as nitrogen or oxygen while in the atmosphere are discussed. Because relatively thick layers of MLI will be required for storage times of a month or more, the transient performance from ground-hold to space-hold of the systems will become important in optimizing the TPS's for many of the missions. The ground-hold performance of several candidate systems are given as well as a qualitative assessment of the transient performance effects.

  13. Using 2,6-dichlorobenzamide (BAM) degrading Aminobacter sp. MSH1 in flow through biofilters--initial adhesion and BAM degradation potentials.

    PubMed

    Albers, Christian Nyrop; Jacobsen, Ole Stig; Aamand, Jens

    2014-01-01

    Micropollutants in groundwater are given significant attention by water companies and authorities due to an increasing awareness that they might be present even above the legal threshold values. As part of our investigations of the possibility to remove the common groundwater pollutant 2,6-dichlorobenzamide (BAM) by introducing the efficient BAM degrader Aminobacter sp. MSH1 into biologically active sand filters, we investigated if the strain adheres to filters containing various filter materials and if the initial adherence and subsequent degradation of BAM could be optimized. We found that most of the inoculated MSH1 cells adhered fast and that parameters like pH and ionic strength had only a minor influence on the adhesion despite huge influence on cell surface hydrophobicity. At the given growth protocol, the MSH1 strain apparently developed a subpopulation that had lost its ability to adhere to the filter materials, which was supported by attempted reinoculation of non-adhered cells. Analysis by quantitative PCR showed that most cells adhered in the top of the filters and that some of these were lost from the filters during initial operation, while insignificant losses occurred after 1 day of operation. The inoculated filters were found to degrade 2.7 μg/L BAM to below 0.1 μg/L at a 1.1-h residence time with insignificant formation of known degradation products. In conclusion, most filter materials and water types should be feasible for inoculation with the MSH1 strain, while more research into degradation at low concentrations and temperatures is needed before this technology is ready for use at actual waterworks.

  14. Trace species detection in the near infrared using Fourier transform broadband cavity enhanced absorption spectroscopy: initial studies on potential breath analytes.

    PubMed

    Denzer, W; Hancock, G; Islam, M; Langley, C E; Peverall, R; Ritchie, G A D; Taylor, D

    2011-02-21

    Cavity enhanced absorption measurements have been made of several species that absorb light between 1.5 and 1.7 µm using both a supercontinuum source and superluminescent light emitting diodes. A system based upon an optical enhancement cavity of relatively high finesse, consisting of mirrors of reflectivity ∼99.98%, and a Fourier transform spectrometer, is demonstrated. Spectra are recorded of isoprene, butadiene, acetone and methane, highlighting problems with spectral interference and unambiguous concentration determinations. Initial results are presented of acetone within a breath-like matrix indicating ppm precision at <∼10 ppm acetone levels. Instrument sensitivities are sufficiently enhanced to enable the detection of atmospheric levels of methane. Higher detection sensitivities are achieved using the supercontinuum source, with a minimum detectable absorption coefficient of ∼4 × 10(-9) cm(-1) reported within a 4 min acquisition time. Finally, two superluminescent light emitting diodes are coupled together to increase the wavelength coverage, and measurements are made simultaneously on acetylene, CO(2), and butadiene. The absorption cross-sections for acetone and isoprene have been measured with an instrumental resolution of 4 cm(-1) and are found to be 1.3 ± 0.1 × 10(-21) cm(2) at a wavelength of 1671.9 nm and 3.6 ± 0.2 × 10(-21) cm(2) at 1624.7 nm, respectively.

  15. Brucella melitensis global gene expression study provides novel information on growth phase-specific gene regulation with potential insights for understanding Brucella:host initial interactions.

    PubMed

    Rossetti, Carlos A; Galindo, Cristi L; Lawhon, Sara D; Garner, Harold R; Adams, L Garry

    2009-05-06

    Brucella spp. are the etiological agents of brucellosis, a zoonotic infectious disease that causes abortion in animals and chronic debilitating illness in humans. Natural Brucella infections occur primarily through an incompletely defined mechanism of adhesion to and penetration of mucosal epithelium. In this study, we characterized changes in genome-wide transcript abundance of the most and the least invasive growth phases of B. melitensis cultures to HeLa cells, as a preliminary approach for identifying candidate pathogen genes involved in invasion of epithelial cells. B. melitensis at the late logarithmic phase of growth are more invasive to HeLa cells than mid-logarithmic or stationary growth phases. Microarray analysis of B. melitensis gene expression identified 414 up- and 40 down-regulated genes in late-log growth phase (the most invasive culture) compared to the stationary growth phase (the least invasive culture). As expected, the majority of up-regulated genes in late-log phase cultures were those associated with growth, including DNA replication, transcription, translation, intermediate metabolism, energy production and conversion, membrane transport, and biogenesis of the cell envelope and outer membrane; while the down-regulated genes were distributed among several functional categories. This Brucella global expression profile study provides novel information on growth phase-specific gene expression. Further characterization of some genes found differentially expressed in the most invasive culture will likely bring new insights into the initial molecular interactions between Brucella and its host.

  16. Characterization of Sequential Collagen-Poly(ethylene glycol) Diacrylat Interpenetrating Networks and Initial Assessment of their Potential for Vascular Tissue Engineering

    PubMed Central

    Munoz-Pinto, Dany J.; Jimenez-Vergara, Andrea Carolina; Gharat, Tanmay; Hahn, Mariah S.

    2014-01-01

    Collagen hydrogels have been widely investigated as scaffolds for vascular tissue engineering due in part to the capacity of collagen to promote robust cell adhesion and elongation. However, collagen hydrogels display relatively low stiffness and strength, are thrombogenic, and are highly susceptible to cell-mediated contraction. In the current work, we develop and characterize a sequentially-formed interpenetrating network (IPN) that retains the benefits of collagen, but which displays enhanced mechanical stiffness and strength, improved thromboresistance, high physical stability and resistance to contraction. In this strategy, we first form a collagen hydrogel, infuse this hydrogel with poly(ethylene glycol) diacrylate (PEGDA), and subsequently crosslink the PEGDA by exposure to longwave UV light. These collagen-PEGDA IPNs allow for cell encapsulation during the fabrication process with greater than 90% cell viability via inclusion of cells within the collagen hydrogel precursor solution. Furthermore, the degree of cell spreading within the IPNs can be tuned from rounded to fully elongated by varying the time delay between the formation of the cell-laden collagen hydrogel and the formation of the PEGDA network. We also demonstrate that these collagen-PEGDA IPNs are able to support the initial stages of smooth muscle cell lineage progression by elongated human mesenchymal stems cells. PMID:25433604

  17. Potential change in flaw geometry of an initially shallow finite-length surface flaw during a pressurized-thermal-shock transient

    SciTech Connect

    Shum, D.K.; Bryson, J.W.; Merkle, J.G.

    1993-09-01

    This study presents preliminary estimates on whether an shallow, axially oriented, inner-surface finite-length flaw in a PWR-RPV would tend to elongate in the axial direction and/or deepen into the wall of the vessel during a postulated PTS transient. Analysis results obtained based on the assumptions of (1) linear-elastic material response, and (2) cladding with same toughness as the base metal, indicate that a nearly semicircular flaw would likely propagate in the axial direction followed by propagation into the wall of the vessel. Note that these results correspond to initiation within the lower-shelf fracture toughness temperature range, and that their general validity within the lower-transition temperature range remains to be determined. The sensitivity of the numerical results aid conclusions to the following analysis assumptions are evaluated: (1) reference flaw geometry along the entire crack front and especially within the cladding region; (2) linear-elastic vs elastic-plastic description of material response; and (3) base-material-only vs bimaterial cladding-base vessel-model assumption. The sensitivity evaluation indicates that the analysis results are very sensitive to the above assumptions.

  18. The Collective Impact Model and Its Potential for Health Promotion: Overview and Case Study of a Healthy Retail Initiative in San Francisco.

    PubMed

    Flood, Johnna; Minkler, Meredith; Hennessey Lavery, Susana; Estrada, Jessica; Falbe, Jennifer

    2015-10-01

    As resources for health promotion become more constricted, it is increasingly important to collaborate across sectors, including the private sector. Although many excellent models for cross-sector collaboration have shown promise in the health field, collective impact (CI), an emerging model for creating larger scale change, has yet to receive much study. Complementing earlier collaboration approaches, CI has five core tenets: a shared agenda, shared measurement systems, mutually reinforcing activities, continuous communication, and a central infrastructure. In this article, we describe the CI model and its key dimensions and constructs. We briefly compare CI to community coalition action theory and discuss our use of the latter to provide needed detail as we apply CI in a critical case study analysis of the Tenderloin Healthy Corner Store Coalition in San Francisco, California. Using Yin's multimethod approach, we illustrate how CI strategies, augmented by the community coalition action theory, are being used, and with what successes or challenges, to help affect community- and policy-level change to reduce tobacco and alcohol advertising and sales, while improving healthy, affordable, and sustainable food access. We discuss the strengths and weaknesses of CI as a framework for health promotion, as well as the benefits, challenges, and initial outcomes of the healthy retail project and its opportunities for scale-up. Implications for health promotion practice and research also are discussed. © 2015 Society for Public Health Education.

  19. Exploring the potential of analysing visual search behaviour data using FROC (free-response receiver operating characteristic) method: an initial study

    NASA Astrophysics Data System (ADS)

    Dong, Leng; Chen, Yan; Dias, Sarah; Stone, William; Dias, Joseph; Rout, John; Gale, Alastair G.

    2017-03-01

    Visual search techniques and FROC analysis have been widely used in radiology to understand medical image perceptual behaviour and diagnostic performance. The potential of exploiting the advantages of both methodologies is of great interest to medical researchers. In this study, eye tracking data of eight dental practitioners was investigated. The visual search measures and their analyses are considered here. Each participant interpreted 20 dental radiographs which were chosen by an expert dental radiologist. Various eye movement measurements were obtained based on image area of interest (AOI) information. FROC analysis was then carried out by using these eye movement measurements as a direct input source. The performance of FROC methods using different input parameters was tested. The results showed that there were significant differences in FROC measures, based on eye movement data, between groups with different experience levels. Namely, the area under the curve (AUC) score evidenced higher values for experienced group for the measurements of fixation and dwell time. Also, positive correlations were found for AUC scores between the eye movement data conducted FROC and rating based FROC. FROC analysis using eye movement measurements as input variables can act as a potential performance indicator to deliver assessment in medical imaging interpretation and assess training procedures. Visual search data analyses lead to new ways of combining eye movement data and FROC methods to provide an alternative dimension to assess performance and visual search behaviour in the area of medical imaging perceptual tasks.

  20. Ports Initiative

    EPA Pesticide Factsheets

    EPA's Ports Initiative works in collaboration with the port industry, communities, and government to improve environmental performance and increase economic prosperity. This effort helps people near ports breath cleaner air and live better lives.

  1. Progress in Initiator Modeling

    SciTech Connect

    Hrousis, C A; Christensen, J S

    2009-05-04

    There is great interest in applying magnetohydrodynamic (MHD) simulation techniques to the designs of electrical high explosive (HE) initiators, for the purpose of better understanding a design's sensitivities, optimizing its performance, and/or predicting its useful lifetime. Two MHD-capable LLNL codes, CALE and ALE3D, are being used to simulate the process of ohmic heating, vaporization, and plasma formation in the bridge of an initiator, be it an exploding bridgewire (EBW), exploding bridgefoil (EBF) or slapper type initiator. The initiation of the HE is simulated using Tarver Ignition & Growth reactive flow models. 1-D, 2-D and 3-D models have been constructed and studied. The models provide some intuitive explanation of the initiation process and are useful for evaluating the potential impact of identified aging mechanisms (such as the growth of intermetallic compounds or powder sintering). The end product of this work is a simulation capability for evaluating margin in proposed, modified or aged initiation system designs.

  2. Synthesis of the first radiolabeled 188Re N-heterocyclic carbene complex and initial studies on its potential use in radiopharmaceutical applications

    PubMed Central

    Wagner, Thomas; Zeglis, Brian M.; Groveman, Sam; Hille, Claudia; Pöthig, Alexander; Francesconi, Lynn C.; Herrmann, Wolfgang A.; Kühn, Fritz E.; Reiner, Thomas

    2015-01-01

    A novel approach towards the synthesis of radiolabeled organometallic rhenium complexes is presented. We successfully synthesized and analyzed the first 188Re-labeled N-heterocyclic biscarbene complex, trans-dioxobis(1,1′-methylene-bis(3,3′-diisopropylimidazolium-2-ylidene))188rhenium(V) hexafluorophosphate (188Re-4) via transmetalation using an air-stable and moisture-stable silver(I) biscarbene complex. In order to assess the viability of this complex as a potential lead structure for in vivo applications, the stability of the 188Re-NHC complex was tested in physiologically relevant media. Ultimately, our studies illustrate that the complex we synthesized dissociates rapidly and is therefore unsuitable for use in radiopharmaceuticals. However, it is clear that the transmetalation approach we have developed is a rapid, robust, and mild method for the synthesis of new 188Re-labeled carbene complexes. PMID:24889257

  3. In vitro refolding of human proinsulin. Kinetic intermediates, putative disulfide-forming pathway folding initiation site, and potential role of C-peptide in folding process.

    PubMed

    Qiao, Zhi-Song; Min, Cheng-Yin; Hua, Qing-Xin; Weiss, Michael A; Feng, You-Min

    2003-05-16

    Human insulin is a double-chain peptide that is synthesized in vivo as a single-chain human proinsulin (HPI). We have investigated the disulfide-forming pathway of a single-chain porcine insulin precursor (PIP). Here we further studied the folding pathway of HPI in vitro. While the oxidized refolding process of HPI was quenched, four obvious intermediates (namely P1, P2, P3, and P4, respectively) with three disulfide bridges were isolated and characterized. Contrary to the folding pathway of PIP, no intermediates with one- or two-disulfide bonds could be captured under different refolding conditions. CD analysis showed that P1, P2, and P3 retained partially structural conformations, whereas P4 contained little secondary structure. Based on the time-dependent distribution, disulfide pair analysis, and disulfide-reshuffling process of the intermediates, we have proposed that the folding pathway of HPI is significantly different from that of PIP. These differences reveal that the C-peptide not only facilitates the folding of HPI but also governs its kinetic folding pathway of HPI. Detailed analysis of the molecular folding process reveals that there are some similar folding mechanisms between PIP and HPI. These similarities imply that the initiation site for the folding of PIP/HPI may reside in the central alpha-helix of the B-chain. The formation of disulfide A20-B19 may guide the transfer of the folding information from the B-chain template to the unstructured A-chain. Furthermore, the implications of this in vitro refolding study on the in vivo folding process of HPI have been discussed.

  4. Rad3-Cds1 mediates coupling of initiation of meiotic recombination with DNA replication. Mei4-dependent transcription as a potential target of meiotic checkpoint.

    PubMed

    Ogino, Keiko; Masai, Hisao

    2006-01-20

    Premeiotic S-phase and meiotic recombination are known to be strictly coupled in Saccharomyces cerevisiae. However, the checkpoint pathway regulating this coupling has been largely unknown. In fission yeast, Rad3 is known to play an essential role in coordination of DNA replication and cell division during both mitotic growth and meiosis. Here we have examined whether the Rad3 pathway also regulates the coupling of DNA synthesis and recombination. Inhibition of premeiotic S-phase with hydroxyurea completely abrogates the progression of meiosis, including the formation of DNA double-strand breaks (DSBs). DSB formation is restored in rad3 mutant even in the presence of hydroxyurea, although repair of DSBs does not take place or is significantly delayed, indicating that the subsequent recombination steps may be still inhibited. Examination of the roles of downstream checkpoint kinases reveals that Cds1, but not Chk1 or Mek1, is required for suppression of DSB in the presence of hydroxyurea. Transcriptional induction of some rec+ genes essential for DSB occurs at a normal timing and to a normal level in the absence of DNA synthesis in both the wild-type and cds1delta cells. On the other hand, the transcriptional induction of the mei4+ transcription factor and cdc25+ phosphatase, which is significantly suppressed by hydroxyurea in the wild-type cells, occurs almost to a normal level in cds1delta cells even in the presence of hydroxyurea. These results show that the Rad3-Cds1 checkpoint pathway coordinates initiation of meiotic recombination and meiotic cell divisions with premeiotic DNA synthesis. Because mei4+ is known to be required for DSB formation and cdc25+ is required for activation of meiotic cell divisions, we propose an intriguing possibility that the Rad3-Cds1 meiotic checkpoint pathway may target transcription of these factors.

  5. The potential of azooxanthellate poriferan hosts to assess the fundamental and realized Symbiodinium niche: evaluating a novel method to initiate Symbiodinium associations

    NASA Astrophysics Data System (ADS)

    Strehlow, Brian; Friday, Sarah; McCauley, Mark; Hill, Malcolm

    2016-12-01

    On coral reefs, Symbiodinium spp. are found in most cnidarian species, but reside in only a small number of sponge species. Of the sponges that do harbor Symbiodinium, most are found in the family Clionaidae, which represents a minor fraction of the poriferan diversity on a reef. Our goal was to determine whether Symbiodinium can be taken up by sponge hosts that do not typically harbor these algal symbionts, and then to follow the fate of any Symbiodinium that enter the intracellular space. We used the filter-feeding capacity of sponges to initiate intracellular interactions between sponge-specialist clade G Symbiodinium and six sponge species that do not associate with Symbiodinium. Using a pulse-chase experimental design, we determined that all of the species we examined captured Symbiodinium, and undamaged intracellular algae were found up to 1 h after inoculation. In a longer-term experiment, Symbiodinium populations in Amphimedon erina persisted in sponge cells for at least 5 d post-inoculation. While no evidence of digestion was detected, the population decreased exponentially after inoculation. We contrast these data with the characteristics of symbiont acquisition and establishment in Cliona varians, which normally harbors Symbiodinium. Explants from experimentally derived aposymbiotic sponges were placed in the field where they acquired Symbiodinium from ambient sources (i.e., we did not inoculate them as in the pulse-chase experiments). We began to detect Symbiodinium cells in C. varians after 12 d, and the algal population increased exponentially until densities approached those typically found in this host (after 128 d). We discuss the implications of this work in light of growing interest in the evolution of specificity between hosts and symbionts, and the fundamental and realized niche of Symbiodinium.

  6. Adult Fanniidae associated to pig carcasses during the winter season in a semiarid environment: initial examination of their potential as complementary PMI indicators.

    PubMed

    Aballay, Fernando H; Domínguez, M Cecilia; Fernández Campón, Florencia

    2012-06-10

    Besides the dominant necrophagous dipteran of the families Sarcophagidae and Calliphoridae usually used for post mortem interval (PMI) estimations, species of other families such as Fanniidae have frequently been reported in forensic studies. Though less abundant, these species are prevalent in decomposing carcasses with most reports being anecdotal. In this study we identified adults of the fly family Fanniidae associated to pig carcasses located under different local environmental conditions (sun and shade) in a semiarid area at Mendoza, Argentina during the winter season. We examined the potential of species of this family as indicators of PMI by measuring abundance, time of occurrence and residency time at the carcasses. We identified six species of Fanniidae: Euryomma peregrinum Meigen, Fannia albitarsis Stein, Fannia femoralis Stein, Fannia fusconotata Rondani, Fannia heydenii Wiedemann and Fannia sanihue Domínguez and Aballay. Overall, fly abundance was higher at the sunlit than at the shaded carcass. The most abundant species at the sun was F. fusconotata while at the shaded carcass F. femoralis was the most abundant species. Based on their residency time, however, species with higher potential as PMI indicators seem to be F. heydenii and F. sanihue as their residency time at the carcass was restricted to a short period of the decomposition process. Other species were present throughout most of the decomposition process or in such a low abundance (E. peregrinum) that they were not useful as indicators. These preliminary results indicate that adults of some species of Fanniidae could act as a good complementary indicator species during the winter season. In particular, F. heydenii and F. sanihue should be the focus of further studies which should also expand to other seasons. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  7. Conformational studies of a peptide corresponding to a region of the C-terminus of ribonuclease A: implications as a potential chain-folding initiation site.

    PubMed

    Beals, J M; Haas, E; Krausz, S; Scheraga, H A

    1991-08-06

    nanosecond time scale, (2) a partially ordered structure of OT-16-DABA exists in solution under typical refolding conditions, and (3) structural constraints (presumably hydrophobic interactions) necessary for the formation of a chain-folding initiation site in RNase A are also present in the OT-16-DABA peptide in the absence of denaturant and are disrupted by Gdn-HCl.

  8. A biocompatible and magnetic nanocarrier with a safe UV-initiated docetaxel release and cancer secretion removal properties increases therapeutic potential for skin cancer.

    PubMed

    Kong, Fei; Huang, Xiao; Yue, Danyang; Pan, Jun

    2017-07-01

    Cancer is a leading fatal disease worldwide. To increase its therapeutic efficiency, more effective with less side effect and patient acceptable administration approach is expected. Moreover, modification of tumor microenvironment is proved to be operative recently. In this paper, a nanocarrier named LDEDDS was developed for intelligent tropical administration of skin cancer, along with removal of hydrophobic cancerous secretion to change tumor microenvironment. It was made by coating of amphipathic polymer P(BA-co-HBA) on docetaxel (TXT, a model hydrophobic anticancer drug) loaded Fe3O4@ZnO. Results showed that an optimal loading rate of TXT in Fe3O4@ZnO was 89.75±0.15%, corresponding to loading capacity of 17.95±2.97% when the mass ratio of Fe3O4@ZnO to TXT was 1:20. The LDEDDS had a narrow distribution size of 115.8nm in average and was superparamagnetic. Without UV radiation, it had low TXT release (<7% in 48h) and cytotoxicity (<14% in 96h) to both the normal and carcinoma skin cells. While under a UV with a dose much lower than physiological dose of normal sunlight, LDEDDS released around 60% and 90% of TXT in 1 and 48h. 1h UV treated LDEDDS removed up to 62% of cancer secreted epidermal growth factor (EGF), a model hydrophobic secretion in 96h. Consequently, 1h UV treated LDEDDS inhibited up to 60% of the growth of skin cancer cells in 96h, overriding those effects of the same concentration of TXT in in vitro cellular experiments. This is the first study to change tumor microenvironment by removal of cancerous secretion and is proved to be effective. Along with the superparamagnetic property, which provides potential for concentrating, increasing penetration and internalization into cancerated cells as well as removing from body under an external magnetic field, we predict LDEDDS will have potential applications in clinic skin cancer therapy. Copyright © 2017. Published by Elsevier B.V.

  9. Semivolatile organic compound emissions from heavy-duty trucks operating on diesel and bio-diesel fuel blends

    EPA Science Inventory

    This study measured semivolatile organic compounds (SVOCs) in particle matter (PM) emitted from three heavy-duty trucks equipped with modern after-treatment technologies. Emissions testing was conducted as described by the George et al. VOC study also presented as part of this se...

  10. Experimental Investigation of Performance and emission characteristics of Various Nano Particles with Bio-Diesel blend on Di Diesel Engine

    NASA Astrophysics Data System (ADS)

    Karthik, N.; Goldwin Xavier, X.; Rajasekar, R.; Ganesh Bairavan, P.; Dhanseelan, S.

    2017-05-01

    Present study provides the effect of Zinc Oxide (ZnO) and Cerium Oxide (CeO2) nanoparticles additives on the Performance and emission uniqueness of Jatropha. Jatropha blended fuel is prepared by the emulsification technique with assist of mechanical agitator. Nano particles (Zinc Oxide (ZnO)) and Cerium Oxide (CeO2)) mixed with Jatropha blended fuel in mass fraction (100 ppm) with assist of an ultrasonicator. Experiments were conducted in single cylinder constant speed direct injection diesel engine for various test fuels. Performance results revealed that Brake Thermal Efficiency (BTE) of Jatropha blended Cerium Oxide (B20CE) is 3% and 11% higher than Jatropha blended zinc oxide (B20ZO) and Jatropha blended fuel (B20) and 4% lower than diesel fuel (D100) at full load conditions. Emission result shows that HC and CO emissions of Jatropha blended Cerium Oxide (B20CE) are (6%, 22%, 11% and 6%, 15%, 12%) less compared with Jatropha blended Zinc Oxide (B20ZO), diesel (D100) and Jatropha blended fuel (B20) at full load conditions. NOx emissions of Jatropha blended Cerium Oxide is 1 % higher than diesel fuel (D100) and 2% and 5% lower than Jatropha blended Zinc Oxide, and jatropha blended fuel.

  11. Semivolatile organic compound emissions from heavy-duty trucks operating on diesel and bio-diesel fuel blends

    EPA Science Inventory

    This study measured semivolatile organic compounds (SVOCs) in particle matter (PM) emitted from three heavy-duty trucks equipped with modern after-treatment technologies. Emissions testing was conducted as described by the George et al. VOC study also presented as part of this se...

  12. Performance and emission parameters of single cylinder diesel engine using castor oil bio-diesel blended fuels

    NASA Astrophysics Data System (ADS)

    Rahimi, A.; Ghobadian, B.; Najafi, G.; Jaliliantabar, F.; Mamat, R.

    2015-12-01

    The purpose of this study is to investigate the performance and emission parameters of a CI single cylinder diesel engine operating on biodiesel-diesel blends (B0, B5, B10, B15 and E20: 20% biodiesel and 80% diesel by volume). A reactor was designed, fabricated and evaluated for biodiesel production. The results showed that increasing the biodiesel content in the blend fuel will increase the performance parameters and decrease the emission parameters. Maximum power was detected for B0 at 2650 rpm and maximum torque was belonged to B20 at 1600 rpm. The experimental results revealed that using biodiesel-diesel blended fuels increased the power and torque output of the engine. For biodiesel blends it was found that the specific fuel consumption (sfc) was decreased. B10 had the minimum amount for sfc. The concentration of CO2 and HC emissions in the exhaust pipe were measured and found to be decreased when biodiesel blends were introduced. This was due to the high oxygen percentage in the biodiesel compared to the net diesel fuel. In contrast, the concentration of CO and NOx was found to be increased when biodiesel is introduced.

  13. Aflatoxin Biosynthesis Is a Novel Source of Reactive Oxygen Species—A Potential Redox Signal to Initiate Resistance to Oxidative Stress?

    PubMed Central

    Roze, Ludmila V.; Laivenieks, Maris; Hong, Sung-Yong; Wee, Josephine; Wong, Shu-Shyan; Vanos, Benjamin; Awad, Deena; Ehrlich, Kenneth C.; Linz, John E.

    2015-01-01

    Aflatoxin biosynthesis in the filamentous fungus Aspergillus parasiticus involves a minimum of 21 enzymes, encoded by genes located in a 70 kb gene cluster. For aflatoxin biosynthesis to be completed, the required enzymes must be transported to specialized early and late endosomes called aflatoxisomes. Of particular significance, seven aflatoxin biosynthetic enzymes are P450/monooxygenases which catalyze reactions that can produce reactive oxygen species (ROS) as byproducts. Thus, oxidative reactions in the aflatoxin biosynthetic pathway could potentially be an additional source of intracellular ROS. The present work explores the hypothesis that the aflatoxin biosynthetic pathway generates ROS (designated as “secondary” ROS) in endosomes and that secondary ROS possess a signaling function. We used specific dyes that stain ROS in live cells and demonstrated that intracellular ROS levels correlate with the levels of aflatoxin synthesized. Moreover, feeding protoplasts with precursors of aflatoxin resulted in the increase in ROS generation. These data support the hypothesis. Our findings also suggest that secondary ROS may fulfill, at least in part, an important mechanistic role in increased tolerance to oxidative stress in germinating spores (seven-hour germlings) and in regulation of fungal development. PMID:25928133

  14. From the flight deck to the operating room: an initial pilot study of the feasibility and potential impact of true interdisciplinary team training using high-fidelity simulation.

    PubMed

    Paige, John; Kozmenko, Valeriy; Morgan, Barbara; Howell, D Shannon; Chauvin, Sheila; Hilton, Charles; Cohn, Isidore; O'Leary, J Patrick

    2007-01-01

    The operating room is a dynamic environment in which proper teamwork is essential. After piloting a simulation-based interdisciplinary operative team training program, we examined the impact of these sessions on the participants. Three interdisciplinary operating room teams participated in the training model. Each team of 3 or 4 members completed the training in a virtual minimally invasive operating room using a standardized operative scenario. Upon completion of the training, participants completed a voluntary and anonymous training effectiveness questionnaire. All 10 participants completed the training evaluation questionnaires. Across the 3 teams, all participants felt that the training was worthwhile and would participate again. Eight participants said that the session would change their practices in the operating room. All participants felt that the session was effective in promoting team communication skills and crisis-related teamwork. Nine of the 10 felt that the training model was effective in recognizing operating room errors. Implementing true interdisciplinary team training with a high-fidelity simulation can be accomplished effectively. Team training has the potential for facilitating positive behavioral changes in operating room personnel that are important for adaptive team function in a crisis situation.

  15. Possibilities and potential roles of the functional peptides based on enamel matrix proteins in promoting the remineralization of initial enamel caries.

    PubMed

    Ieong, Cheng Cheng; Zhou, Xue Dong; Li, Ji Yao; Li, Wei; Zhang, Ling Lin

    2011-03-01

    Dental caries is the most common oral diseases, and it gives a serious threat to oral and general health. Fluoride, a classic anti-caries agent, has a profound effect on caries prevention and treatment. However, fluorosis and fluoride-resistant strains limit the further application of fluoride treatment. Therefore, it is still of significant benefit to seek alternatives, bringing more effective anti-caries agents. The potential role of enamel matrix proteins(EMPs) in promoting the regeneration of periodontal tissue and inducing bone have been proved. EMPs have been successfully applied in the field of periodontal disease and dental implants in recent years. Previous researches revealed that enamel matrix proteins had an important role in the synthesis of hydroxyapatite in vitro. Some experiments about the degeneration or removal of EMP suggest that enamel matrix proteins are related to the occurrence and development of caries. Based on evidences illustrated by these experiments, this paper hypothesizes that functional peptides based on the function and structure of EMPs could promote remineralization of enamel caries, which could perform as a suitable treatment to enamel caries. The hypothesis may lead a new direction in the study on the prevention and treatment of enamel caries, and further study of the anti-caries mechanisms of EMP will enable researchers to find out the most effective anti-caries peptides, which could be developed into a bionics anti-cariogenic agent. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Remineralization potential of bioactive glass and casein phosphopeptide-amorphous calcium phosphate on initial carious lesion: An in-vitro pH-cycling study

    PubMed Central

    Mehta, Adit Bharat; Kumari, Veena; Jose, Rani; Izadikhah, Vajiheh

    2014-01-01

    Aims: The aim of this study was to evaluate and compare the remineralization potential of bioactive-Glass (BAG) (Novamin®/Calcium-sodium-phosphosilicate) and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) containing dentifrice. Materials and Methods: A total of 30 sound human premolars were decoronated, coated with nail varnish except for a 4 mm × 4 mm window on the buccal surface of crown and were randomly divided in two groups (n = 15). Group A — BAG dentifrice and Group B — CPP-ACP dentifrice. The baseline surface microhardness (SMH) was measured for all the specimens using the vickers microhardness testing machine. Artificial enamel carious lesions were created by inserting the specimens in de-mineralizing solution for 96 h. SMH of demineralized specimens was evaluated. 10 days of pH-cycling regimen was carried out. SMH of remineralized specimens was evaluated. Statistical Analysis: Data was analyzed using ANOVA and multiple comparisons within groups was done using Bonferroni method (post-hoc tests) to detect significant differences at P < 0.05 levels. Results: Group A showed significantly higher values (P < 0.05) when compared with the hardness values of Group B. Conclusions: Within the limits; the present study concluded that; both BAG and CPP-ACP are effective in remineralizing early enamel caries. Application of BAG more effectively remineralized the carious lesion when compared with CPP-ACP. PMID:24554851

  17. GIS-NaP1 zeolite microspheres as potential water adsorption material: Influence of initial silica concentration on adsorptive and physical/topological properties

    PubMed Central

    Sharma, Pankaj; Song, Ju-Sub; Han, Moon Hee; Cho, Churl-Hee

    2016-01-01

    GIS-NaP1 zeolite samples were synthesized using seven different Si/Al ratios (5–11) of the hydrothermal reaction mixtures having chemical composition Al2O3:xSiO2:14Na2O:840H2O to study the impact of Si/Al molar ratio on the water vapour adsorption potential, phase purity, morphology and crystal size of as-synthesized GIS-NaP1 zeolite crystals. The X-ray diffraction (XRD) observations reveal that Si/Al ratio does not affect the phase purity of GIS-NaP1 zeolite samples as high purity GIS-NaP1 zeolite crystals were obtained from all Si/Al ratios. Contrary, Si/Al ratios have remarkable effect on the morphology, crystal size and porosity of GIS-NaP1 zeolite microspheres. Transmission electron microscopy (TEM) evaluations of individual GIS-NaP1 zeolite microsphere demonstrate the characteristic changes in the packaging/arrangement, shape and size of primary nano crystallites. Textural characterisation using water vapour adsorption/desorption, and nitrogen adsorption/desorption data of as-synthesized GIS-NaP1 zeolite predicts the existence of mix-pores i.e., microporous as well as mesoporous character. High water storage capacity 1727.5 cm3 g−1 (138.9 wt.%) has been found for as-synthesized GIS-NaP1 zeolite microsphere samples during water vapour adsorption studies. Further, the total water adsorption capacity values for P6 (1299.4 mg g−1) and P7 (1388.8 mg g−1) samples reveal that these two particular samples can absorb even more water than their own weights. PMID:26964638

  18. Countdown to Drawdown: an initial overview of exponential scaling of potential societal tipping points for deep decarbonization of global energy infrastructure by 2050

    NASA Astrophysics Data System (ADS)

    McCaffrey, Mark; Bhowmik, Avit

    2017-04-01

    The 194 signatories to the Paris Agreement range in size from small island nations (Tuvalu, less than 10,000 people) to massive states (India and China, which between them have 2.6 billion people). Their cultural backgrounds, political, economic and social systems vary widely. What they all share is an agreement for climate stabilisation at 1.5-2˚ C. A roadmap outlining potential exponential transitions towards a carbon-free economy may benefit from a logarithmic "powers of ten" framework that sets aside backgrounds and systems to examine the relative population concentration scales-from the individual (100) to local/neighborhood (103) to the national/transnational scales (108) and ultimately the global population of around 10 billion anticipated in 2050 (1010). What are the related targets and indicators for successful engagement at each level for rapid and radical reductions of carbon emissions and concentrations? What are the possible interventions and barriers that may be applied at different levels of population concentration? What "drawdown" strategies are most appropriate for different scales? Could focusing demonstrations of clean energy and sustainable practices on the local/neighborhood to urban scale (103-104) provide a leverage that has not been achieved at more complex national and transnational scales? Ultimately, backgrounds and systems are important factors in the equation, but the "powers of 10" scaling framework may provide a compass to assist in identifying the challenges, opportunities and related thresholds and tipping points for achieving deep decarbonization and transformation of the global energy infrastructure at every level of society over the next thirty-three years.

  19. In vivo evaluation of the genetic toxicity of Rubus niveus Thunb. (Rosaceae) extract and initial screening of its potential chemoprevention against doxorubicin-induced DNA damage.

    PubMed

    Tolentino, Flora; Araújo, Priscila Alves de; Marques, Eduardo de Souza; Petreanu, Marcel; Andrade, Sérgio Faloni de; Niero, Rivaldo; Perazzo, Fábio F; Rosa, Paulo César Pires; Maistro, Edson Luis

    2015-04-22

    Rubus niveus Thunb. plant belongs to Rosaceae family and have been used traditionally to treat wounds, burns, inflammation, dysentery, diarrhea and for curing excessive bleeding during menstrual cycle. The present study was undertaken to investigate the in vivo genotoxicity of Rubus niveus aerial parts extract and its possible chemoprotection on doxorubicin (DXR)-induced DNA damage. In parallel, the main phytochemicals constituents in the extract were determined. The animals were exposed to the extract for 24 and 48 h, and the doses selected were 500, 1000 and 2000 mg/kg b.w. administered by gavage alone or prior to DXR (30 mg/kg b.w.) administered by intraperitoneal injection. The endpoints analyzed were DNA damage in bone marrow and peripheral blood cells assessed by the alkaline alkaline (pH>13) comet assay and bone marrow micronucleus test. The results of chemical analysis of the extract showed the presence of tormentic acid, stigmasterol, quercitinglucoronide (miquelianin) and niga-ichigoside F1 as main compounds. Both cytogenetic endpoints analyzed showed that there were no statistically significant differences (p>0.05) between the negative control and the treated groups with the two higher doses of Rubus niveus extract alone, demonstrating absence of genotoxic and mutagenic effects. Aneugenic/clastogenic effect was observed only at 2000 mg/kg dose. On the other hand, in the both assays and all tested doses were observed a significant reduction of DNA damage and chromosomal aberrations in all groups co-treated with DXR and extract compared to those which received only DXR. These results indicate that Rubus niveus aerial parts extract did not revealed any genotoxic effect, but presented some aneugenic/clastogenic effect at higher dose; and suggest that it could be a potential adjuvant against development of second malignant neoplasms caused by the cancer chemotherapic DXR. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  20. GIS-NaP1 zeolite microspheres as potential water adsorption material: Influence of initial silica concentration on adsorptive and physical/topological properties

    NASA Astrophysics Data System (ADS)

    Sharma, Pankaj; Song, Ju-Sub; Han, Moon Hee; Cho, Churl-Hee

    2016-03-01

    GIS-NaP1 zeolite samples were synthesized using seven different Si/Al ratios (5–11) of the hydrothermal reaction mixtures having chemical composition Al2O3:xSiO2:14Na2O:840H2O to study the impact of Si/Al molar ratio on the water vapour adsorption potential, phase purity, morphology and crystal size of as-synthesized GIS-NaP1 zeolite crystals. The X-ray diffraction (XRD) observations reveal that Si/Al ratio does not affect the phase purity of GIS-NaP1 zeolite samples as high purity GIS-NaP1 zeolite crystals were obtained from all Si/Al ratios. Contrary, Si/Al ratios have remarkable effect on the morphology, crystal size and porosity of GIS-NaP1 zeolite microspheres. Transmission electron microscopy (TEM) evaluations of individual GIS-NaP1 zeolite microsphere demonstrate the characteristic changes in the packaging/arrangement, shape and size of primary nano crystallites. Textural characterisation using water vapour adsorption/desorption, and nitrogen adsorption/desorption data of as-synthesized GIS-NaP1 zeolite predicts the existence of mix-pores i.e., microporous as well as mesoporous character. High water storage capacity 1727.5 cm3 g‑1 (138.9 wt.%) has been found for as-synthesized GIS-NaP1 zeolite microsphere samples during water vapour adsorption studies. Further, the total water adsorption capacity values for P6 (1299.4 mg g‑1) and P7 (1388.8 mg g‑1) samples reveal that these two particular samples can absorb even more water than their own weights.

  1. GIS-NaP1 zeolite microspheres as potential water adsorption material: Influence of initial silica concentration on adsorptive and physical/topological properties.

    PubMed

    Sharma, Pankaj; Song, Ju-Sub; Han, Moon Hee; Cho, Churl-Hee

    2016-03-11

    GIS-NaP1 zeolite samples were synthesized using seven different Si/Al ratios (5-11) of the hydrothermal reaction mixtures having chemical composition Al2O3:xSiO2:14Na2O:840H2O to study the impact of Si/Al molar ratio on the water vapour adsorption potential, phase purity, morphology and crystal size of as-synthesized GIS-NaP1 zeolite crystals. The X-ray diffraction (XRD) observations reveal that Si/Al ratio does not affect the phase purity of GIS-NaP1 zeolite samples as high purity GIS-NaP1 zeolite crystals were obtained from all Si/Al ratios. Contrary, Si/Al ratios have remarkable effect on the morphology, crystal size and porosity of GIS-NaP1 zeolite microspheres. Transmission electron microscopy (TEM) evaluations of individual GIS-NaP1 zeolite microsphere demonstrate the characteristic changes in the packaging/arrangement, shape and size of primary nano crystallites. Textural characterisation using water vapour adsorption/desorption, and nitrogen adsorption/desorption data of as-synthesized GIS-NaP1 zeolite predicts the existence of mix-pores i.e., microporous as well as mesoporous character. High water storage capacity 1727.5 cm(3) g(-1) (138.9 wt.%) has been found for as-synthesized GIS-NaP1 zeolite microsphere samples during water vapour adsorption studies. Further, the total water adsorption capacity values for P6 (1299.4 mg g(-1)) and P7 (1388.8 mg g(-1)) samples reveal that these two particular samples can absorb even more water than their own weights.

  2. Initiating and potentiating role of platelets in tissue factor-induced thrombin generation in the presence of plasma: subject-dependent variation in thrombogram characteristics.

    PubMed

    Vanschoonbeek, K; Feijge, M A H; Van Kampen, R J W; Kenis, H; Hemker, H C; Giesen, P L A; Heemskerk, J W M

    2004-03-01

    The hemostatic activity of plasma is determined by platelet activation and coagulation, which processes are mutually stimulatory. We studied this interaction by measuring the cleavage of fluorescent thrombin substrate in platelet-rich plasma (PRP), using the calibrated thrombogram method. In freshly isolated human plasma, thrombin formation triggered by tissue factor was fully dependent on the presence of platelets. It was abolished by annexin A5, indicating dependence on phosphatidylserine (PS) exposure at activated platelets. Comparison of plasmas from various subjects showed considerable interindividual variation in total amount of thrombin generation, regardless of whether platelets or PS-containing phospholipids were present. Integrin alphaIIbbeta3 antagonists and ADP receptor blockage, but not aspirin, decreased the rate of thrombin generation (thrombin peak level) and extended the time of onset. Platelet inhibition with cAMP-elevating agents decreased the thrombin-forming rate, but surprisingly shortened the onset time. Stimulation of platelets with agonists of Gi/q-coupled receptors and, to a larger extent, with collagen or Ca2+-ionophore increased the rate of thrombin generation and shortened its onset. In PRP from donors with low and high generation, platelet inhibitors and activators were similarly effective. Taken together, these results indicate that, in tissue factor-triggered PRP, PS exposure on activated platelets regulates both onset and rate of thrombin generation. However, coagulant activity rather than platelet activation determines the total amount of thrombin formed, i.e. the endogenous thrombin potential. Thus, kinetics of thrombin generation in PRP are controlled by platelet inhibitors and agonists, but the process is restricted in amount by the subject-dependent variation in coagulation.

  3. Intraoperative cortico-cortical evoked potentials for the evaluation of language function during brain tumor resection: initial experience with 13 cases.

    PubMed

    Saito, Taiichi; Tamura, Manabu; Muragaki, Yoshihiro; Maruyama, Takashi; Kubota, Yuichi; Fukuchi, Satoko; Nitta, Masayuki; Chernov, Mikhail; Okamoto, Saori; Sugiyama, Kazuhiko; Kurisu, Kaoru; Sakai, Kuniyoshi L; Okada, Yoshikazu; Iseki, Hiroshi

    2014-10-01

    The objective in the present study was to evaluate the usefulness of cortico-cortical evoked potentials (CCEP) monitoring for the intraoperative assessment of speech function during resection of brain tumors. Intraoperative monitoring of CCEP was applied in 13 patients (mean age 34 ± 14 years) during the removal of neoplasms located within or close to language-related structures in the dominant cerebral hemisphere. For this purpose strip electrodes were positioned above the frontal language area (FLA) and temporal language area (TLA), which were identified with direct cortical stimulation and/or preliminary mapping with the use of implanted chronic subdural grid electrodes. The CCEP response was defined as the highest observed negative peak in either direction of stimulation. In 12 cases the tumor was resected during awake craniotomy. An intraoperative CCEP response was not obtained in one case because of technical problems. In the other patients it was identified from the FLA during stimulation of the TLA (7 cases) and from the TLA during stimulation of the FLA (5 cases), with a mean peak latency of 83 ± 15 msec. During tumor resection the CCEP response was unchanged in 5 cases, decreased in 4, and disappeared in 3. Postoperatively, all 7 patients with a decreased or absent CCEP response after lesion removal experienced deterioration in speech function. In contrast, in 5 cases with an unchanged intraoperative CCEP response, speaking abilities after surgery were preserved at the preoperative level, except in one patient who experienced not dysphasia, but dysarthria due to pyramidal tract injury. This difference was statistically significant (p < 0.01). The time required to recover speech function was also significantly associated with the type of intraoperative change in CCEP recordings (p < 0.01) and was, on average, 1.8 ± 1.0, 5.5 ± 1.0, and 11.0 ± 3.6 months, respectively, if the response was unchanged, was decreased, or had disappeared. Monitoring CCEP is

  4. [Changes in mitochondrial membrane potentials and its exponential relation with phosphatidylserine translocation in the plasma membrane as markers in the initial events of apoptosis: evaluation in different spermatic fractions].

    PubMed

    Barroso Villa, Gerardo; Karchmer Krivitzky, Samuel; Castelazo Morales, Ernesto; Carballo Mondragón, Esperanza; Kably Ambe, Alberto

    2002-04-01

    To determine the integrity of the plasmatic membrane through phosphatidylserine (PS) translocation in two spermatic fractions and their correlation with the spermatic mitochondrial membrane potential. The analysis of both spermatic fractions was carried out through a discontinuous gradient separation with Percoli, in order to obtain two samples with high and low mobility (90-40%). Twelve patients were recruited for the initial evaluation of seminal parameters. Mitochondrial membrane integrity was determined using a second antibody (Mitosensor), and was analyzed by fluorescence microscopy, evaluating an average of 200 cells. A 450-490 nm excitation filter was used for this analysis. Cytoplasmatic assessment was carried out by anexine V bonding to PS, in order to determine the initial events of cellular death. Non parameter tests were used in order to determine the differences between mitochondrial potentials and plasmatic membrane processes. Linear correlation tests were used for the anexine V and Mitosensor ratios. Due to the study's design, some differences were observed regarding the displacement parameters and the presence of apoptosis, both, in the plasmatic membrane and in mitochondrial membrane potentials. A positive correlation between both, mitochondrial and cytoplasmic membrane functions was also found. This is the first study performing a comparative analysis between mitochondrial membrane function and cytoplasmatic PS expression as early cellular death markers. The male infertility population is probably associated with an increase in this kind of apoptosis processes.

  5. Youth Initiatives.

    ERIC Educational Resources Information Center

    Employment and Training Administration (DOL), Washington, DC. Office of Youth Programs.

    Summarizing the first eight months of the planning, design, and implementation of the new federal youth programs created by the Youth Employment and Demonstration Projects Act of 1977 (YEDPA) and the efforts for expansion and enrichment of the Job Corps, this report explains the charters of the two projects and their initial successes in and…

  6. Study of the OH and Cl-initiated oxidation, IR absorption cross-section, radiative forcing, and global warming potential of four C4-hydrofluoroethers.

    PubMed

    Oyaro, Nathan; Sellevåg, Stig R; Nielsen, Claus J

    2004-11-01

    Infrared absorption cross-sections and OH and Cl reaction rate coefficients for four C4-hydrofluoroethers (CF3)2CHOCH3, CF3CH2OCH2CF3, CF3CF2CH2OCH3, and CHF2CF2CH2OCH3 are reported. Relative rate measurements at 298 K and 1013 hPa of OH and Cl reaction rate coefficients give k(OH+(CF3)2CHOCH3) = (1.27+/-0.13) x 10(-13), k(OH+CF3CH2OCH2CF3) = (1.51+/-0.24) x 10(-13), k(OH+CF3CF2CH2OCH3) = (6.42+/-0.33) x 10(-13), k(OH+CHF2CF2CH2OCH3) = (8.7 +/-0.5) x 10(-13), k(Cl+(CF3)2CHOCH3) = (8.4+/-1.3) x 10(-12), k(Cl+CF3CH2OCH2CF3) = (6.5+/-1.7) x 10(-13), k(Cl+CF3CF2CH2OCH3) = (4.0+/-0.8) x 10(-11), and k(Cl+CHF2CF2CH2OCH3) = (2.65+/-0.17) x 10(-11) cm3 molecule(-1) s(-1). The primary products of the OH and Cl reactions with the fluorinated ethers have been identified as esters, and OH and Cl reaction rate coefficients for one of these, CF3CH2OCHO, are reported: k(OH+CF3CH2OCHO) = (7.7+/-0.9) x 10(-14) and kCl+CF3CH2OCHO) = (6.3+/-1.9) x 10(-14) cm3 molecule(-1) s(-1) The rate coefficient for the Cl-atom reaction with CHF2CH2F is derived as k(Cl+CHF2CH2F) = (3.0+/-0.9) x 10(-14) cm3 molecule(-1) s(-1) at 298 K. The error limits include 3sigma from the statistical data analyses as well as the errors in the rate coefficients of the reference compounds employed. The tropospheric lifetimes of the hydrofluoroethers are estimated to be short tauOH((CF3)2CHOCH3) approximately 100 days, tauOH(CF3CH2OCH2CF3) approximately 80 days, tauOH(CF3CF2CH2OCH3) approximately 20 days, and tauOH(CHF2CF2CH2OCH3) approximately 14 days, and their global warming potentials are small compared to CFC-11.

  7. SCB initiator

    DOEpatents

    Bickes Jr., Robert W.; Renlund, Anita M.; Stanton, Philip L.

    1994-11-01

    A detonator for high explosives initiated by mechanical impact includes a cylindrical barrel, a layer of flyer material mechanically covering the barrel at one end, and a semiconductor bridge ignitor including a pair of electrically conductive pads connected by a semiconductor bridge. The bridge is in operational contact with the layer, whereby ignition of said bridge forces a portion of the layer through the barrel to detonate the explosive. Input means are provided for igniting the semiconductor bridge ignitor.

  8. SCB initiator

    DOEpatents

    Bickes, Jr., Robert W.; Renlund, Anita M.; Stanton, Philip L.

    1994-01-01

    A detonator for high explosives initiated by mechanical impact includes a cylindrical barrel, a layer of flyer material mechanically covering the barrel at one end, and a semiconductor bridge ignitor including a pair of electrically conductive pads connected by a semiconductor bridge. The bridge is in operational contact with the layer, whereby ignition of said bridge forces a portion of the layer through the barrel to detonate the explosive. Input means are provided for igniting the semiconductor bridge ignitor.

  9. Advanced Building Efficiency Testbed Initiative/Intelligent Workplace Energy Supply System; ABETI/IWESS

    SciTech Connect

    David Archer; Frederik Betz; Yun Gu; Rong Li; Flore Marion; Sophie Masson; Ming Qu; Viraj Srivastava; Hongxi Yin; Chaoqin Zhai; Rui Zhang; Elisabeth Aslanian; Berangere Lartigue

    2008-05-31

    ABETI/IWESS is a project carried out by Carnegie Mellon's Center for Building Performance and Diagnostics, the CBPD, supported by the U.S. Department of Energy/EERE, to design, procure, install, operate, and evaluate an energy supply system, an ESS, that will provide power, cooling, heating and ventilation for CBPD's Intelligent Workplace, the IW. The energy sources for this system, the IWESS, are solar radiation and bioDiesel fuel. The components of this overall system are: (1) a solar driven cooling and heating system for the IW comprising solar receivers, an absorption chiller, heat recovery exchanger, and circulation pump; (2) a bioDiesel fueled engine generator with heat recovery exchangers, one on the exhaust to provide steam and the other on the engine coolant to provide heated water; (3) a ventilation system including an enthalpy recovery wheel, an air based heat pump, an active desiccant wheel, and an air circulation fan; and (4) various convective and radiant cooling/heating units and ventilation air diffusers distributed throughout the IW. The goal of the ABETI/IWESS project is to demonstrate an energy supply system for a building space that will provide a healthy, comfortable environment for the occupants and that will reduce the quantity of energy consumed in the operation of a building space by a factor of 2 less than that of a conventional energy supply for power, cooling, heating, and ventilation based on utility power and natural gas fuel for heating.

  10. Openness initiative

    SciTech Connect

    Duncan, S.S.

    1995-12-31

    Although antinuclear campaigns seem to be effective, public communication and education efforts on low-level radioactive waste have mixed results. Attempts at public information programs on low-level radioactive waste still focus on influencing public opinion. A question then is: {open_quotes}Is it preferable to have a program focus on public education that will empower individuals to make informed decisions rather than trying to influence them in their decisions?{close_quotes} To address this question, a case study with both quantitative and qualitative data will be used. The Ohio Low-Level Radioactive Waste Education Program has a goal to provide people with information they want/need to make their own decisions. The program initiated its efforts by conducting a statewide survey to determine information needed by people and where they turned for that information. This presentation reports data from the survey and then explores the program development process in which programs were designed and presented using the information. Pre and post data from the programs reveal attitude and knowledge shifts.

  11. OSM's reforestation initiative

    SciTech Connect

    Boyce, J.S.

    1999-07-01

    Implementation of the Surface Mining Control and Reclamation Act (SMCRA) has discouraged reforestation in some situations where reforestation would be desirable. OSM is engaged in an initiative to increase the amount of mined land reclaimed to forest where appropriate. The authors are seeking to determine those elements of the Federal/State regulator programs that discourage reforestation and find ways to offset these impacts. Potential factors militating against reforestation are identified and possible solutions are discussed.

  12. Investigating the potential of using tree-ring records and river-dammed lake sediments to reconstruct paleohydrology in the Virgin River watershed, southern Utah: Initial observations and results

    NASA Astrophysics Data System (ADS)

    Rittenour, T.

    2008-12-01

    The Virgin River drains an area of over 13,000 km2 in southern Utah, northern Arizona and southern Nevada before entering into Lake Mead as a major tributary to the Colorado River. Peak flood discharges occur during the spring snowmelt runoff and floods related to monsoon-driven mid-summer convective storms (USGS gage data). Years with above average winter snowpack and high spring meltwater discharges have been linked to El Nino conditions, annual droughts correlate to La Nina years (e.g. Brown and Comrie, 2004). Weather station and river gage records used to reconstruct precipitation and flood frequency are limited to the last century. However, slackwater flood deposits (Enzel et al., 1994) and tree-ring (e.g. Hereford et al. 2006) and lake sediment records may be able to extend this record over the last several thousand years. Research has begun to investigate the use of tree-ring records from the middle to upper Virgin River watershed in southern Utah for paleohydrologic reconstruction. Initial pinyon pine tree-ring measurements show a good relationship to precipitation, peak spring snowmelt runoff and annual discharge in the North Fork of the Virgin River. One year lags in tree-ring thickness are common within the record due to energy storage from a preceding wetter year. Additional tree cores from a number of species and locations within the watershed are needed to produce an accurate tree-ring index and paleohydrologic reconstruction. In addition to tree-ring records, sediment archives within the Virgin River drainage are being examined for their potential for paleoflood reconstruction. A large landslide within Zion Canyon in Zion National Park dammed the North Fork of the Virgin 8000 years ago and created a 60 m deep lake that existed until just after 3600 years ago (Biek et al., 2000). Lake sediments consist of alternating coarse (silty-sand and fine sand) and fine-grained layers (clay, clayey-silt, silt). Initial descriptions suggest that these coarse

  13. Murine stromal cells counteract the loss of long-term culture-initiating cell potential induced by cytokines in CD34(+)CD38(low/neg) human bone marrow cells.

    PubMed

    Bennaceur-Griscelli, A; Tourino, C; Izac, B; Vainchenker, W; Coulombel, L

    1999-07-15

    Evidence has been provided recently that shows that high concentrations of cytokines can fulfill functions previously attributed to stromal cells, such as promote the survival of, and led to a net increase in human primitive progenitors initiating long-term cultures in vitro (LTC-IC) or engrafting NOD-SCID (nonobese diabetic severe-combined immunodeficient) recipients in vivo. These data prompted us to re-evaluate whether stromal cells will further alter the properties of primitive progenitor cells exposed to cytokines. Single CD34(+)CD38(low) and CD38(neg) cells were incubated 10 days in serum-containing or serum-free medium in the presence or in the absence of murine marrow-derived stromal cells (MS-5). Recombinant human cytokines stem cell factor (SCF), pegylated-megakaryocyte growth and differentiation factor (PEG-MGDF), FLT3-L, Interleukin (IL)-3, IL-6, and granulocyte-macrophage colony-stimulating factor (GM-CSF) were systematically added at various concentrations (10 to 300 ng/mL). Cell proliferation and LTC-IC potential were evaluated in each clone after 10 days. A striking and consistent observation was the retention of a high LTC-IC potential in clones exposed to cytokines in the presence of stromal feeders, whereas clones exposed to cytokines alone in the absence of stromal feeders rapidly lost their LTC-IC potential as they proliferated. This was reflected both by the higher proportion of wells containing LTC-IC and by the high numbers of CFC produced after 5 weeks in clones grown with MS-5 during the first 10 days. We further showed by analyzing multiple replicates of a single clone at day 10 that MS-5 cells promoted a net increase in the LTC-IC compartment through self-renewal divisions. Interestingly, these primitive LTC-IC were equally distributed among small and large clones, as counted at day 10, indicating that active proliferation and loss of LTC-IC potential could be dissociated. These observations show that, in primitive cells, stromal cells

  14. Potential and Challenges of Low-Cost and High-Tech Crowd-sensing Approaches in Hydrometeorology for Better Water Resources Management - Insights and Learnings from the Global iMoMo Initiative

    NASA Astrophysics Data System (ADS)

    Siegfried, Tobias

    2016-04-01

    In developing and transition countries and despite significant global investments in hydrometeorology, data on water remain scarce/fragmented. One key reason is that traditional sensing in hydrology, hydro- and agro-meteorology does not scale because of high investment costs and difficult maintenance of traditional technology, esp. in remote and/or poor regions. Even where there are data, these are often difficult to access and interpret for local stakeholders due outdated data transmission and the lack of access to modern tools for data management/analysis/synthesis and exchange. In recent years, there have been substantial technology developments in environmental sensing and mobile communication technology that enable the application and deployment of affordable and scalable high-tech solutions for better water monitoring at different scales (local to transboundary levels). The WMO is acknowledging and promoting the potential for application of these technologies. One key aspect is to anchor these technologies in local communities that perform crowd-sensing tasks on a regular basis. The merits as well as challenges (including introduction of human factor, less accuracy as compared to traditional sensing, intermittency of data, …) of such approaches will be discussed in the context of the WMO-led Global iMoMo Initiative and its numerous activities on the ground in Eastern and Southern Africa as well as in Central Asia.

  15. 'Can he have the test for bipolar, doctor? His dad's got it': exploring the potential of general practitioners to work with children and young people presenting in primary care with common mental health problems - a clinical initiative.

    PubMed

    Roberts, Jane H; Bernard, Paul M

    2012-06-01

    Background General practitioners (GPs) play a key role in assessing and managing adult mental health problems, but this input is not seen in their management of child and adolescent mental health. Mental health problems in 5-19-year-olds are common, yet detection rates in primary care are low. The symptoms of most adult diagnoses of mental health problems are present by mid-adolescence, yet the typical time from onset to diagnosis is 5-15 years. The role of general practice in this area has been underexplored. Aim This pilot study explores the potential of GPs to respond to common mental health problems in children and adolescents. Design Children and young people who would have ordinarily been referred to Child and Adolescent Mental Health Services (CAMHS) were seen in a GP setting. In a UK general practice surgery serving a disadvantaged population. Method Children and young people were seen for an initial biopsychosocial assessment and formulation of the presenting concerns. GP-based interventions were offered as appropriate or referred to CAMHS. Results Data from the first 50 children (2-19 years) are presented. Twenty younger children (10 years and under) and 30 older children (11 years and above) were seen. Eighteen referrals were made to CAMHS. GP interventions included watchful waiting, brief behavioural interventions, non-directive counselling, brief cognitive- behavioural therapy (CBT) and liaison with colleagues in education, CAMHS and the voluntary sector. Conclusion This clinical pilot demonstrates that with adequate time, access to supervision and practice support, children and young people experiencing emotional and behavioural problems associated with common mental health issues can be helped in primary care.

  16. ‘Can he have the test for bipolar, doctor? His dad's got it’: exploring the potential of general practitioners to work with children and young people presenting in primary care with common mental health problems – a clinical initiative

    PubMed Central

    2012-01-01

    Background General practitioners (GPs) play a key role in assessing and managing adult mental health problems, but this input is not seen in their management of child and adolescent mental health. Mental health problems in 5–19-year-olds are common, yet detection rates in primary care are low. The symptoms of most adult diagnoses of mental health problems are present by mid-adolescence, yet the typical time from onset to diagnosis is 5–15 years. The role of general practice in this area has been underexplored. Aim This pilot study explores the potential of GPs to respond to common mental health problems in children and adolescents. Design Children and young people who would have ordinarily been referred to Child and Adolescent Mental Health Services (CAMHS) were seen in a GP setting. In a UK general practice surgery serving a disadvantaged population. Method Children and young people were seen for an initial biopsychosocial assessment and formulation of the presenting concerns. GP-based interventions were offered as appropriate or referred to CAMHS. Results Data from the first 50 children (2–19 years) are presented. Twenty younger children (10 years and under) and 30 older children (11 years and above) were seen. Eighteen referrals were made to CAMHS. GP interventions included watchful waiting, brief behavioural interventions, non-directive counselling, brief cognitive– behavioural therapy (CBT) and liaison with colleagues in education, CAMHS and the voluntary sector. Conclusion This clinical pilot demonstrates that with adequate time, access to supervision and practice support, children and young people experiencing emotional and behavioural problems associated with common mental health issues can be helped in primary care. PMID:23730336

  17. 29 CFR 1990.142 - Initiation of a rulemaking.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) IDENTIFICATION, CLASSIFICATION, AND REGULATION OF POTENTIAL OCCUPATIONAL CARCINOGENS Regulation of Potential Occupational Carcinogens § 1990.142 Initiation of a rulemaking. Where the Secretary decides to regulate a potential occupational carcinogen, the Secretary shall initiate a rulemaking...

  18. 29 CFR 1990.142 - Initiation of a rulemaking.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) IDENTIFICATION, CLASSIFICATION, AND REGULATION OF POTENTIAL OCCUPATIONAL CARCINOGENS Regulation of Potential Occupational Carcinogens § 1990.142 Initiation of a rulemaking. Where the Secretary decides to regulate a potential occupational carcinogen, the Secretary shall initiate a rulemaking...

  19. 29 CFR 1990.142 - Initiation of a rulemaking.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) IDENTIFICATION, CLASSIFICATION, AND REGULATION OF POTENTIAL OCCUPATIONAL CARCINOGENS Regulation of Potential Occupational Carcinogens § 1990.142 Initiation of a rulemaking. Where the Secretary decides to regulate a potential occupational carcinogen, the Secretary shall initiate a rulemaking...

  20. 29 CFR 1990.142 - Initiation of a rulemaking.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) IDENTIFICATION, CLASSIFICATION, AND REGULATION OF POTENTIAL OCCUPATIONAL CARCINOGENS Regulation of Potential Occupational Carcinogens § 1990.142 Initiation of a rulemaking. Where the Secretary decides to regulate a potential occupational carcinogen, the Secretary shall initiate a rulemaking...

  1. 29 CFR 1990.142 - Initiation of a rulemaking.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) IDENTIFICATION, CLASSIFICATION, AND REGULATION OF POTENTIAL OCCUPATIONAL CARCINOGENS Regulation of Potential Occupational Carcinogens § 1990.142 Initiation of a rulemaking. Where the Secretary decides to regulate a potential occupational carcinogen, the Secretary shall initiate a rulemaking...

  2. Initial conditions for inflation

    NASA Astrophysics Data System (ADS)

    Dimopoulos, Konstantinos; Artymowski, Michał

    2017-09-01

    Within the α-attractors framework we investigate scalar potentials with the same pole as the one featured in the kinetic term. We show that, in field space, this leads to directions without a plateau. Using this, we present a proposal, which manages to overcome the initial conditions problem of inflation with a plateau. An earlier period of proto-inflation, beginning at Planck scale, accounts for the Universe expansion and arranges the required initial conditions for inflation on the plateau to commence. We show that, if proto-inflation is power-law, it does not suffer from a sub-Planckian eternal inflationary stage, which would otherwise be a problem. A simple model realisation is constructed in the context of α-attractors, which can both generate the inflationary plateau and the exponential slopes around it, necessary for the two inflation stages. Our mechanism allows to assume chaotic initial conditions at the Planck scale for proto-inflation, it is generic and it is shown to work without fine-tuning.

  3. CD49f and CD61 identify Her2/neu-induced mammary tumor initiating cells that are potentially derived from luminal progenitors and maintained by the integrin-TGFβ signaling

    PubMed Central

    Lo, Pang-Kuo; Kanojia, Deepak; Liu, Xinfeng; Singh, Udai P.; Berger, Franklin G.; Wang, Qian; Chen, Hexin

    2011-01-01

    HER2/Neu is overexpressed in 20-30% of breast cancers and associated with aggressive phenotypes and poor prognosis. For deciphering the role of HER2/Neu in breast cancer, mouse mammary tumor virus (MMTV)-Her2/neu transgenic mice that develop mammary tumors resembling human HER2-subtype breast cancer have been established. Several recent studies have revealed that HER2/Neu is overexpressed in and regulates self renewal of breast tumor initiating cells (TICs). However, in the MMTV-Her2/neu transgenic mouse model, the identity of TICs remains elusive, despite previous studies showing supportive evidence for existence of TICs in Her2/neu-induced mammary tumors. Through systematic screening and characterization, we identified surface markers CD49f, CD61 and ESA were aberrantly overexpressed in Her2-overexpressing mammary tumor cells. Analysis of these markers as well as CD24 detected anomalous expansion of the luminal progenitor population in preneoplastic mammary glands of Her2/neu-transgenic mice, indicating that aberrant luminal progenitors originated Her2-induced mammary tumors. The combined markers, CD49f and CD61, further delineated the CD49fhighCD61high-sorted fraction as a TIC-enriched population, which displayed increased tumorsphere formation ability, enhanced tumorigenicity both in vitro and in vivo and drug resistance to pacitaxel and doxorubicin. Moreover, the TIC-enriched population manifested increased TGFβ signaling and exhibited gene expression signatures of stemness, TGFβ signaling and Epithelial-to-Mesenchymal Transition. Our findings that self-renewal and clonogenicity of TICs were suppressed by pharmacologically inhibiting the TGFβ signaling further indicate that the TGFβ pathway is vital for maintenance of the TIC population. Finally, we showed that the integrin β3 (CD61) signaling pathway was required for sustaining active TGFβ signaling and self-renewal of TICs. We for the first time developed a technique to highly enrich TICs from mammary

  4. Iterative initial condition reconstruction

    NASA Astrophysics Data System (ADS)

    Schmittfull, Marcel; Baldauf, Tobias; Zaldarriaga, Matias

    2017-07-01

    Motivated by recent developments in perturbative calculations of the nonlinear evolution of large-scale structure, we present an iterative algorithm to reconstruct the initial conditions in a given volume starting from the dark matter distribution in real space. In our algorithm, objects are first moved back iteratively along estimated potential gradients, with a progressively reduced smoothing scale, until a nearly uniform catalog is obtained. The linear initial density is then estimated as the divergence of the cumulative displacement, with an optional second-order correction. This algorithm should undo nonlinear effects up to one-loop order, including the higher-order infrared resummation piece. We test the method using dark matter simulations in real space. At redshift z =0 , we find that after eight iterations the reconstructed density is more than 95% correlated with the initial density at k ≤0.35 h Mpc-1 . The reconstruction also reduces the power in the difference between reconstructed and initial fields by more than 2 orders of magnitude at k ≤0.2 h Mpc-1 , and it extends the range of scales where the full broadband shape of the power spectrum matches linear theory by a factor of 2-3. As a specific application, we consider measurements of the baryonic acoustic oscillation (BAO) scale that can be improved by reducing the degradation effects of large-scale flows. In our idealized dark matter simulations, the method improves the BAO signal-to-noise ratio by a factor of 2.7 at z =0 and by a factor of 2.5 at z =0.6 , improving standard BAO reconstruction by 70% at z =0 and 30% at z =0.6 , and matching the optimal BAO signal and signal-to-noise ratio of the linear density in the same volume. For BAO, the iterative nature of the reconstruction is the most important aspect.

  5. Home initiation of parenteral nutrition.

    PubMed

    Newton, Alyce F; DeLegge, Mark H

    2007-02-01

    Parenteral nutrition (PN) has been successfully initiated in the home since the early 1990s. The American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) Standards for Specialized Nutrition Support: Home Care Patients, Safe Practices for Parenteral Nutrition, and Guidelines for the Use of Parenteral and Enteral Nutrition in Adult and Pediatric Patients do not contain specific information on the initiation of home PN (HPN). Peer-reviewed, published guidelines are necessary to provide safe and appropriate initiation of HPN. Certain patients should not have PN initiated in the home, such as those with organ failure, uncontrolled diabetes, or uncorrectable electrolyte abnormalities. Excellent candidates for initiation of HPN include patients who have failed enteral feedings, have gastrointestinal (GI) diseases without excessive GI losses, or those with an oncology diagnosis and inability to tube feed. One concern of initiation of HPN is the potential for refeeding syndrome. Refeeding syndrome can be prevented when patients are properly evaluated and managed before initiation of PN. Refeeding syndrome can be avoided by rehydration with fluid and electrolytes before initiation of HPN to normalize blood chemistry when necessary and by starting with a moderate-volume, low-carbohydrate HPN solution compounded with optimal potassium, phosphorus, and magnesium content, and slowly advanced to goal. The "start low and go slow" motto of nutrition support should continue to be followed, but more specific guidelines are needed to assist nutrition support clinicians with safe and appropriate initiation of HPN.

  6. Manufacturing vegetable oil based biodiesel: An engineering management perspective

    USDA-ARS?s Scientific Manuscript database

    According to the USDA, 6.45 million tons of cottonseed was produced in 2007. Each ton will yield approximately 44 to 46 gallons unrefined oil. Cottonseed oil bio-diesel could have the potential to create a more competitive oil market for oil mills. The proposed cost model is based on an existing cot...

  7. Extraction of proteins from pennycress seeds and press cake

    USDA-ARS?s Scientific Manuscript database

    In order to more fully utilize pennycress, a potentially viable bio-diesel source, the proteinaceous components were extracted from pennycress seed and press cake. The amino acid composition of the proteins present in pennycress was typical for proteins derived from plants, with glycine, glutamic ac...

  8. Feasibility Study of Biopower in East Helena, Montana. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    SciTech Connect

    Moriarty, K.

    2013-02-01

    The U.S. Environmental Protection Agency (EPA) developed the RE-Powering America's Land initiative to reuse contaminated sites for renewable energy generation when aligned with the community's vision for the site. The former American Smelting and Refining Company (Asarco) smelter in East Helena, Montana, was selected for a feasibility study under the initiative. Biomass was chosen as the renewable energy resource based on the wood products industry in the area. Biopower was selected as the technology based on Montana's renewable portfolio standard (RPS) requiring utilities to purchase renewable power.

  9. Combat Wound Initiative program.

    PubMed

    Stojadinovic, Alexander; Elster, Eric; Potter, Benjamin K; Davis, Thomas A; Tadaki, Doug K; Brown, Trevor S; Ahlers, Stephen; Attinger, Christopher E; Andersen, Romney C; Burris, David; Centeno, Jose; Champion, Hunter; Crumbley, David R; Denobile, John; Duga, Michael; Dunne, James R; Eberhardt, John; Ennis, William J; Forsberg, Jonathan A; Hawksworth, Jason; Helling, Thomas S; Lazarus, Gerald S; Milner, Stephen M; Mullick, Florabel G; Owner, Christopher R; Pasquina, Paul F; Patel, Chirag R; Peoples, George E; Nissan, Aviram; Ring, Michael; Sandberg, Glenn D; Schaden, Wolfgang; Schultz, Gregory S; Scofield, Tom; Shawen, Scott B; Sheppard, Forest R; Stannard, James P; Weina, Peter J; Zenilman, Jonathan M

    2010-07-01

    The Combat Wound Initiative (CWI) program is a collaborative, multidisciplinary, and interservice public-private partnership that provides personalized, state-of-the-art, and complex wound care via targeted clinical and translational research. The CWI uses a bench-to-bedside approach to translational research, including the rapid development of a human extracorporeal shock wave therapy (ESWT) study in complex wounds after establishing the potential efficacy, biologic mechanisms, and safety of this treatment modality in a murine model. Additional clinical trials include the prospective use of clinical data, serum and wound biomarkers, and wound gene expression profiles to predict wound healing/failure and additional clinical patient outcomes following combat-related trauma. These clinical research data are analyzed using machine-based learning algorithms to develop predictive treatment models to guide clinical decision-making. Future CWI directions include additional clinical trials and study centers and the refinement and deployment of our genetically driven, personalized medicine initiative to provide patient-specific care across multiple medical disciplines, with an emphasis on combat casualty care.

  10. Initiating and Growing an Axon

    PubMed Central

    Polleux, F.; Snider, William

    2010-01-01

    The ability of neurons to form a single axon and multiple dendrites underlies the directional flow of information transfer in the central nervous system. Dendrites and axons are molecularly and functionally distinct domains. Dendrites integrate synaptic inputs, triggering the generation of action potentials at the level of the soma. Action potentials then propagate along the axon, which makes presynaptic contacts onto target cells. This article reviews what is known about the cellular and molecular mechanisms underlying the ability of neurons to initiate and extend a single axon during development. Remarkably, neurons can polarize to form a single axon, multiple dendrites, and later establish functional synaptic contacts in reductionist in vitro conditions. This approach became, and remains, the dominant model to study axon initiation and growth and has yielded the identification of many molecules that regulate axon formation in vitro ( Dotti et al. 1988). At present, only a few of the genes identified using in vitro approaches have been shown to be required for axon initiation and outgrowth in vivo. In vitro, axon initiation and elongation are largely intrinsic properties of neurons that are established in the absence of relevant extracellular cues. However, the importance of extracellular cues to axon initiation and outgrowth in vivo is emerging as a major theme in neural development ( Barnes and Polleux 2009). In this article, we focus our attention on the extracellular cues and signaling pathways required in vivo for axon initiation and axon extension. PMID:20452947

  11. The Plus 50 Initiative Evaluation: Initiative Impact

    ERIC Educational Resources Information Center

    American Association of Community Colleges (NJ1), 2012

    2012-01-01

    The American Association of Community Colleges (AACC), with funding from The Atlantic Philanthropies, created the Plus 50 Initiative (2008-2012). This initiative was designed to build the capacity of community colleges nationwide to develop programming that engages the plus 50 learner. This report contains: (1) An overview of the Plus 50…

  12. Stirling to Flight Initiative

    NASA Technical Reports Server (NTRS)

    Hibbard, Kenneth E.; Mason, Lee S.; Ndu, Obi; Smith, Clayton; Withrow, James P.

    2016-01-01

    NASA has a consistent need for radioisotope power systems (RPS) to enable robotic scientific missions for planetary exploration that has been present for over four decades and will continue into the foreseeable future, as documented in the most recent Planetary Science Decadal Study Report. As RPS have evolved throughout the years, there has also grown a desire for more efficient power systems, allowing NASA to serve as good stewards of the limited plutonium-238 (238Pu), while also supporting the ever-present need to minimize mass and potential impacts to the desired science measurements. In fact, the recent Nuclear Power Assessment Study (NPAS) released in April 2015 resulted in several key conclusion regarding RPS, including affirmation that RPS will be necessary well into the 2030s (at least) and that 238Pu is indeed a precious resource requiring efficient utilization and preservation. Stirling Radioisotope Generators (SRGs) combine a Stirling cycle engine powered by a radioisotope heater unit into a single generator system. Stirling engine technology has been under development at NASA Glenn Research Center (GRC) in partnership with the Department of Energy (DOE) since the 1970's. The most recent design, the 238Pu-fueled Advanced Stirling Radioisotope Generator (ASRG), was offered as part of the NASA Discovery 2010 Announcement of Opportunity (AO). The Step-2 selections for this AO included two ASRG-enabled concepts, the Titan Mare Explorer (TiME) and the Comet Hopper (CHopper), although the only non-nuclear concept, InSight, was ultimately chosen. The DOE's ASRG contract was terminated in 2013. Given that SRGs utilize significantly less 238Pu than traditional Radioisotope Thermoelectric Generators (RTGs) - approximately one quarter of the nuclear fuel, to produce similar electrical power output - they provide a technology worthy of consideration for meeting the aforementioned NASA objectives. NASA's RPS Program Office has recently investigated a new Stirling to

  13. Initialized Fractional Calculus

    NASA Technical Reports Server (NTRS)

    Lorenzo, Carl F.; Hartley, Tom T.

    2000-01-01

    This paper demonstrates the need for a nonconstant initialization for the fractional calculus and establishes a basic definition set for the initialized fractional differintegral. This definition set allows the formalization of an initialized fractional calculus. Two basis calculi are considered; the Riemann-Liouville and the Grunwald fractional calculi. Two forms of initialization, terminal and side are developed.

  14. Heat fluctuations and initial ensembles.

    PubMed

    Kim, Kwangmoo; Kwon, Chulan; Park, Hyunggyu

    2014-09-01

    Time-integrated quantities such as work and heat increase incessantly in time during nonequilibrium processes near steady states. In the long-time limit, the average values of work and heat become asymptotically equivalent to each other, since they only differ by a finite energy change in average. However, the fluctuation theorem (FT) for the heat is found not to hold with the equilibrium initial ensemble, while the FT for the work holds. This reveals an intriguing effect of everlasting initial memory stored in rare events. We revisit the problem of a Brownian particle in a harmonic potential dragged with a constant velocity, which is in contact with a thermal reservoir. The heat and work fluctuations are investigated with initial Boltzmann ensembles at temperatures generally different from the reservoir temperature. We find that, in the infinite-time limit, the FT for the work is fully recovered for arbitrary initial temperatures, while the heat fluctuations significantly deviate from the FT characteristics except for the infinite initial-temperature limit (a uniform initial ensemble). Furthermore, we succeed in calculating finite-time corrections to the heat and work distributions analytically, using the modified saddle point integral method recently developed by us. Interestingly, we find noncommutativity between the infinite-time limit and the infinite-initial-temperature limit for the probability distribution function (PDF) of the heat.

  15. MONTANA PALLADIUM RESEARCH INITIATIVE

    SciTech Connect

    Peters, John; McCloskey, Jay; Douglas, Trevor; Young, Mark; Snyder, Stuart; Gurney, Brian

    2012-05-09

    Project Objective: The overarching objective of the Montana Palladium Research Initiative is to perform scientific research on the properties and uses of palladium in the context of the U.S. Department of Energy's Hydrogen, Fuel Cells and Infrastructure Technologies Program. The purpose of the research will be to explore possible palladium as an alternative to platinum in hydrogen-economy applications. To achieve this objective, the Initiatives activities will focus on several cutting-edge research approaches across a range of disciplines, including metallurgy, biomimetics, instrumentation development, and systems analysis. Background: Platinum-group elements (PGEs) play significant roles in processing hydrogen, an element that shows high potential to address this need in the U.S. and the world for inexpensive, reliable, clean energy. Platinum, however, is a very expensive component of current and planned systems, so less-expensive alternatives that have similar physical properties are being sought. To this end, several tasks have been defined under the rubric of the Montana Palladium Research Iniative. This broad swath of activities will allow progress on several fronts. The membrane-related activities of Task 1 employs state-of-the-art and leading-edge technologies to develop new, ceramic-substrate metallic membranes for the production of high-purity hydrogen, and develop techniques for the production of thin, defect-free platinum group element catalytic membranes for energy production and pollution control. The biomimetic work in Task 2 explores the use of substrate-attached hydrogen-producing enzymes and the encapsulation of palladium in virion-based protein coats to determine their utility for distributed hydrogen production. Task 3 work involves developing laser-induced breakdown spectroscopy (LIBS) as a real-time, in situ diagnostic technique to characterize PGEs nanoparticles for process monitoring and control. The systems engineering work in task 4 will

  16. Feasibility Study of Anaerobic Digestion of Food Waste in St. Bernard, Louisiana. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    SciTech Connect

    Moriarty, K.

    2013-01-01

    The U.S. Environmental Protection Agency (EPA) developed the RE-Powering America's Land initiative to re-use contaminated sites for renewable energy generation when aligned with the community's vision for the site. The former Kaiser Aluminum Landfill in St. Bernard Parish, Louisiana, was selected for a feasibility study under the program. Preliminary work focused on selecting a biomass feedstock. Discussions with area experts, universities, and the project team identified food wastes as the feedstock and anaerobic digestion (AD) as the technology.

  17. Initiation of lymphocyte DNA synthesis.

    PubMed

    Coffman, F D; Fresa, K L; Cohen, S

    1991-01-01

    The initiation of DNA replication in T lymphocytes appears to be regulated by two distinct activities: one associated with proliferation which mediates initiation, and another associated with quiescence which blocks initiation. Activated lymphocytes and proliferating lymphoid cell lines produce an activity, termed ADR, which can initiate DNA replication in isolated, quiescent nuclei. ADR is heat-labile, has protease activity or interacts closely with a protease, and is distinct from the DNA polymerases. ADR activity is absent in quiescent lymphocytes and appears in mitogen-stimulated lymphocytes after IL-2 binding. The generation of active ADR appears to be mediated by phosphorylation of a precursor which is present in resting cells. Nuclei from mitogen-unresponsive lymphocytes fail to initiate DNA replication in response to ADR, of potential importance in the age-related decline of immunity. Quiescent lymphocytes lack ADR and synthesize an ADR-inhibitory activity. The ADR inhibitor is a heat-stable protein which suppresses the initiation of DNA synthesis, but is ineffective at suppressing elongation once DNA strand replication has begun. Nuclei from several neoplastic cell lines fail to respond to the ADR inhibitor, which may play a role in the continuous proliferation of these cells. At least one of these neoplastic cell lines produces both ADR and an inhibitory factor. These findings suggest that the regulation of proliferation is dependent on the balance between activating and inhibitory pathways.

  18. Dioxin Exposure Initiative

    EPA Pesticide Factsheets

    The Dioxin Exposure Initiative (DEI) is no longer active. This page contains a summary of the dioxin exposure initiative with illustrations, contact and background information.Originally supported by scientist Matthew Lorber, who retired in Mar 2017.

  19. Metaloxide--ZrO2 catalysts for the esterification and transesterification of free fatty acids and triglycerides to obtain bio-diesel

    DOEpatents

    Kim, Manhoe; Salley, Steven O.; Ng, K. Y. Simon

    2016-09-06

    Mixed metal oxide catalysts (ZnO, CeO, La2O3, NiO, Al203, SiO2, TiO2, Nd2O3, Yb2O3, or any combination of these) supported on zirconia (ZrO2) or hydrous zirconia are provided. These mixed metal oxide catalysts can be prepared via coprecipitation, impregnation, or sol-gel methods from metal salt precursors with/without a Zirconium salt precursor. Metal oxides/ZrO2 catalyzes both esterification and transesterification of oil containing free fatty acids in one batch or in single stage. In particular, these mixed metal oxides supported or added on zirconium oxide exhibit good activity and selectivity for esterification and transesterification. The low acid strength of this catalyst can avoid undesirable side reaction such as alcohol dehydration or cracking of fatty acids. Metal oxides/ZrO2 catalysts are not sensitive to any water generated from esterification. Thus, esterification does not require a water free condition or the presence of excess methanol to occur when using the mixed metal oxide catalyst. The FAME yield obtained with metal oxides/ZrO2 is higher than that obtained with homogeneous sulfuric acid catalyst. Metal oxides/ZrO2 catalasts can be prepared as strong pellets and in various shapes for use directly in a flow reactor. Furthermore, the pellet has a strong resistance toward dissolution to aqueous or oil phases.

  20. Initial Cladding Condition

    SciTech Connect

    E. Siegmann

    2000-08-22

    The purpose of this analysis is to describe the condition of commercial Zircaloy clad fuel as it is received at the Yucca Mountain Project (YMP) site. Most commercial nuclear fuel is encased in Zircaloy cladding. This analysis is developed to describe cladding degradation from the expected failure modes. This includes reactor operation impacts including incipient failures, potential degradation after reactor operation during spent fuel storage in pool and dry storage and impacts due to transportation. Degradation modes include cladding creep, and delayed hydride cracking during dry storage and transportation. Mechanical stresses from fuel handling and transportation vibrations are also included. This Analysis and Model Report (AMR) does not address any potential damage to assemblies that might occur at the YMP surface facilities. Ranges and uncertainties have been defined. This analysis will be the initial boundary condition for the analysis of cladding degradation inside the repository. In accordance with AP-2.13Q, ''Technical Product Development Planning'', a work plan (CRWMS M&O 2000c) was developed, issued, and utilized in the preparation of this document. There are constraints, caveats and limitations to this analysis. This cladding degradation analysis is based on commercial Pressurized Water Reactor (PWR) fuel with Zircaloy cladding but is applicable to Boiling Water Reactor (BWR) fuel. Reactor operating experience for both PWRs and BWRs is used to establish fuel reliability from reactor operation. It is limited to fuel exposed to normal operation and anticipated operational occurrences (i.e. events which are anticipated to occur within a reactor lifetime), and not to fuel that has been exposed to severe accidents. Fuel burnup projections have been limited to the current commercial reactor licensing environment with restrictions on fuel enrichment, oxide coating thickness and rod plenum pressures. The information provided in this analysis will be used in

  1. Feasibility Study of Economics and Performance of a Hydroelectric Installation at the Jeddo Mine Drainage Tunnel. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    SciTech Connect

    Roberts, J. O.; Mosey, G.

    2013-02-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Jeddo Tunnel discharge site for a feasibility study of renewable energy potential. The purpose of this report is to assess technical and economic viability of the site for hydroelectric and geothermal energy production. In addition, the report outlines financing options that could assist in the implementation of a system.

  2. Initiation of vascular development.

    PubMed

    Ohashi-Ito, Kyoko; Fukuda, Hiroo

    2014-06-01

    The initiation of vascular development occurs during embryogenesis and the development of lateral organs, such as lateral roots and leaves. Understanding the mechanism underlying the initiation of vascular development has been an important goal of plant biologists. Auxin flow is a crucial factor involved in the initiation of vascular development. In addition, recent studies have identified key factors that regulate the establishment of vascular initial cells in embryos and roots. In this review, we summarize the recent findings in this field and discuss the initiation of vascular development.

  3. Initial Events in Bacterial Transcription Initiation

    PubMed Central

    Ruff, Emily F.; Record, M. Thomas; Artsimovitch, Irina

    2015-01-01

    Transcription initiation is a highly regulated step of gene expression. Here, we discuss the series of large conformational changes set in motion by initial specific binding of bacterial RNA polymerase (RNAP) to promoter DNA and their relevance for regulation. Bending and wrapping of the upstream duplex facilitates bending of the downstream duplex into the active site cleft, nucleating opening of 13 bp in the cleft. The rate-determining opening step, driven by binding free energy, forms an unstable open complex, probably with the template strand in the active site. At some promoters, this initial open complex is greatly stabilized by rearrangements of the discriminator region between the −10 element and +1 base of the nontemplate strand and of mobile in-cleft and downstream elements of RNAP. The rate of open complex formation is regulated by effects on the rapidly-reversible steps preceding DNA opening, while open complex lifetime is regulated by effects on the stabilization of the initial open complex. Intrinsic DNA opening-closing appears less regulated. This noncovalent mechanism and its regulation exhibit many analogies to mechanisms of enzyme catalysis. PMID:26023916

  4. Extraction of medium chain fatty acids from organic municipal waste and subsequent production of bio-based fuels.

    PubMed

    Kannengiesser, Jan; Sakaguchi-Söder, Kaori; Mrukwia, Timo; Jager, Johannes; Schebek, Liselotte

    2016-01-01

    This paper provides an overview on investigations for a new technology to generate bio-based fuel additives from bio-waste. The investigations are taking place at the composting plant in Darmstadt-Kranichstein (Germany). The aim is to explore the potential of bio-waste as feedstock in producing different bio-based products (or bio-based fuels). For this investigation, a facultative anaerobic process is to be integrated into the normal aerobic waste treatment process for composting. The bio-waste is to be treated in four steps to produce biofuels. The first step is the facultative anaerobic treatment of the waste in a rotting box namely percolate to generate a fatty-acid rich liquid fraction. The Hydrolysis takes place in the rotting box during the waste treatment. The organic compounds are then dissolved and transferred into the waste liquid phase. Browne et al. (2013) describes the hydrolysis as an enzymatically degradation of high solid substrates to soluble products which are further degraded to volatile fatty acids (VFA). This is confirmed by analytical tests done on the liquid fraction. After the percolation, volatile and medium chain fatty acids are found in the liquid phase. Concentrations of fatty acids between 8.0 and 31.5 were detected depending on the nature of the input material. In the second step, a fermentation process will be initiated to produce additional fatty acids. Existing microorganism mass is activated to degrade the organic components that are still remaining in the percolate. After fermentation the quantity of fatty acids in four investigated reactors increased 3-5 times. While fermentation mainly non-polar fatty acids (pentanoic to octanoic acid) are build. Next to the fermentation process, a chain-elongation step is arranged by adding ethanol to the fatty acid rich percolate. While these investigations a chain-elongation of mainly fatty acids with pair numbers of carbon atoms (acetate, butanoic and hexanoic acid) are demonstrated. After

  5. CubeSat Launch Initiative

    NASA Technical Reports Server (NTRS)

    Higginbotham, Scott

    2016-01-01

    The National Aeronautics and Space Administration (NASA) recognizes the tremendous potential that CubeSats (very small satellites) have to inexpensively demonstrate advanced technologies, collect scientific data, and enhance student engagement in Science, Technology, Engineering, and Mathematics (STEM). The CubeSat Launch Initiative (CSLI) was created to provide launch opportunities for CubeSats developed by academic institutions, non-profit entities, and NASA centers. This presentation will provide an overview of the CSLI, its benefits, and its results.

  6. Guam Initial Technical Assessment Report

    SciTech Connect

    Baring-Gould, I.; Conrad, M.; Haase, S.; Hotchkiss, E.; McNutt, P.

    2011-04-01

    Under an interagency agreement, funded by the Department of Interior's (DOI) Office of Insular Affairs (OIA), the National Renewable Energy Laboratory (NREL) was tasked to deliver technical assistance to the island of Guam by conducting an island initial technical assessment that would lay out energy consumption and production data and establish a baseline. This assessment will be used to conduct future analysis and studies by NREL that will estimate energy efficiency and renewable energy potential for the island of Guam.

  7. Potential role of fluctuations in the composition of renal tubular fluid through the nephron in the initiation of Randall's plugs and calcium oxalate crystalluria in a computer model of renal function.

    PubMed

    Robertson, W G

    2015-01-01

    This article describes an updated computer model which attempts to simulate known renal reabsorption and secretion activity through the nephron (NEPHROSIM) and its possible relevance to the initiation of calcium-containing renal stones. The model shows that, under certain conditions of plasma composition, de novo nucleation of both calcium oxalate (CaOx) and calcium phosphate (CaP) can take place at the end of the descending limb of the Loop of Henle (DLH), particularly in untreated, recurrent idiopathic CaOx stone-formers (RSF). The model incorporates a number of hydrodynamic factors that may influence the subsequent growth of crystals nucleated at the end of the DLH as they progress down the renal tubules. These include the fact that (a) crystals of either CaOx or CaP nucleated at the end of the DLH and travelling close to the walls of the tubule travel at slower velocities than the fluid flowing at the central axis of the tubule, (b) the transit of CaOx crystals travelling close to the tubule walls may be delayed for up to at least 25 min, during which time the crystals may continue to grow if the relative supersaturation with respect to CaOx (RSS CaOx) is high enough and (c) such CaOx crystals may stop moving or even fall back in upward-draining collecting ducts (CD) owing to the Stokes gravitational effect. The model predicts, firstly, that for small, transient increases in plasma oxalate concentration, crystallisation only takes place in the CD and leads to the formation of small crystals which are comfortably passed in the urine and, secondly, that for slightly greater increases in the filtered load of oxalate, spontaneous and/or heterogeneous nucleation of CaOx may occur both at the end of the DLH and in the CD. This latter situation leads to the passage in the final urine of a mixture of large crystals of CaOx (arising from nucleation at the end of the DLH) and small crystals of CaOx (as a result of nucleation originating in the CD). As a result of the

  8. Initial Experience of the Application of Automated Tube Potential Selection Technique in High-pitch Dual-source CT Angiography of Whole Aorta Using Third-generation Dual-source CT Scanner.

    PubMed

    Kong, Lingyan; Liang, Jixiang; Xue, Huadan; Wang, Yining; Wang, Yun; Jin, Zhengyu; Zhang, Daming; Chen, Jin

    2017-02-20

    Objective To evaluate the application of automated tube potential selection technique in high-pitch dual-source CT aortic angiography on a third-generation dual-source CT scanner. Methods Whole aorta angiography were indiated in 59 patients,who were divided into 2 groups using a simple random method:in group 1 there were 31 patients who underwent the examination with automated tube potential selection using a vascular setting with a preferred image quality of 288 mA/100 kV;in group 2 there were 28 patients who underwent the examination with a tube voltage of 100 kV and automated tube current modulation using a reference tube current of 288 mA. Both groups were scanned on a third generation dual-source CT device operated in dual-source high-pitch ECG-gating mode with a pitch of 3.0,collimation of 2×192×0.6 mm,and a rotation time of 0.25 s. Iterative reconstruction algorithm was used. For group 1,the volume and flow of contrast medium and chasing saline were adapted to the tube voltage. For group 2,a contrast material bolus of 45 ml with a flow of 4.5 ml/s followed by a 50 ml saline chaser at 5 ml/s was used. CTA scan was automatically started using a bolus tracking technique at the level of the original part of aorta after a trigger threshold of 100 HU was reached. The start delay was set to 6 s in both groups. Effective dose (ED),signal to noise ratio (SNR),contrast to noise ratio (CNR),and subjective diagnostic quality of both groups were evaluated. Results The mean ED were 21.3% lower (t=-3.099,P=0.000) in group 1 [(2.48±0.80) mSv] than in group 2 [(3.15±0.86) mSv]. Two groups showed no significant difference in attenuation,SD,SNR,or CNR at all evaluational parts of aorta (ascending aorta,aortic arch,diaphragmatic aorta,or iliac bifurcation)(all P>0.05). There was no significant difference in subjective diagnostic quality values of two groups [(1.41±0.50) scores vs. (1.39±0.50) scores;W=828.5,P=0.837]. Conclusion Compared with automated tube current

  9. Potential role of the posterior cruciate ligament synovio-entheseal complex in joint effusion in early osteoarthritis: a magnetic resonance imaging and histological evaluation of cadaveric tissue and data from the Osteoarthritis Initiative

    PubMed Central

    Binks, D.A.; Bergin, D.; Freemont, A.J.; Hodgson, R.J.; Yonenaga, T.; McGonagle, D.; Radjenovic, A.

    2014-01-01

    Summary Objective This study explored posterior cruciate ligament (PCL) synovio-entheseal complex (SEC) microanatomy to determine whether it may participate in the early osteoarthritis (OA) disease process. Methods SEC microanatomy and OA features were evaluated in 14 non-arthritic cadaveric knees (mean age = 69.9) using magnetic resonance imaging (MRI) and histology. MRI images of 49 subjects selected from the progression cohort of the Osteoarthritis Initiative (OAI) were evaluated by a musculoskeletal radiologist using an original semi-quantitative method for features associated with OA at the PCL tibial enthesis. Statistical analysis was performed using chi-square and Wilcoxon signed-rank tests to evaluate associations between SEC configuration and OA features. Results The PCL formed a SEC-like structure encompassing bone- and ligament-lining intra-articular cartilages to which the posterior root of the medial meniscus contributed. Degenerative features at the PCL-SEC included: neovascularisation (44%), enthesis chondrocyte clustering (44%), collagen matrix fissuring at the enthesis (56%) and in the PCL itself (67%), tidemark duplication (44%), bone remodelling (44%) and microscopic inflammatory changes (33%). In the OAI cohort, SEC-related pathology included bone marrow lesions (BMLs) (69%) and osteophytosis (94%) at locations that corresponded to SEC-related cartilages. Posterior joint recess effusion (49%) was linked to MRI abnormalities at PCL-SEC cartilages (χ2 = 7.27, P = 0.007). Conclusions The PCL has a prominent SEC configuration that is associated with microscopic OA changes in aged clinically non-diseased joints. MRI determined knee OA commonly exhibited pathological features at this site which was associated with adjacent joint effusion. Thus, the PCL-SEC could play a hitherto unappreciated role in the early OA disease process. PMID:25008208

  10. Atmospheric Degradation Initiated by OH Radicals of the Potential Foam Expansion Agent, CF3(CF2)2CH═CH2 (HFC-1447fz): Kinetics and Formation of Gaseous Products and Secondary Organic Aerosols.

    PubMed

    Jiménez, Elena; González, Sergio; Cazaunau, Mathieu; Chen, Hui; Ballesteros, Bernabé; Daële, Véronique; Albaladejo, José; Mellouki, Abdelwahid

    2016-02-02

    The assessment of the atmospheric impact of the potential foam expansion agent, CF3(CF2)2CH═CH2 (HFC-1447fz), requires the knowledge of its degradation routes, oxidation products, and radiative properties. In this paper, the gas-phase reactivity of HFC-1447fz with OH radicals is presented as a function of temperature, obtaining kOH (T = 263-358 K) = (7.4 ± 0.4) × 10(-13)exp{(161 ± 16)/T} (cm(3)·molecule(-1)·s(-1)) (uncertainties: ±2σ). The formation of gaseous oxidation products and secondary organic aerosols (SOAs) from the OH + HFC-1447fz reaction was investigated in the presence of NOx at 298 K. CF3(CF2)2CHO was observed at low- and high-NOx conditions. Evidence of SOA formation (ultrafine particles in the range 10-100 nm) is reported with yields ranging from 0.12 to 1.79%. In addition, the absolute UV (190-368 nm) and IR (500-4000 cm(-1)) absorption cross-sections of HFC-1447fz were determined at room temperature. No appreciable absorption in the solar actinic region (λ > 290 nm) was observed, leaving the removal by OH radicals as the main atmospheric loss process for HFC-1447fz. The major contribution of the atmospheric loss of HFC-1447fz is due to OH reaction (84%), followed by ozone (10%) and chlorine atoms (6%). Correction of the instantaneous radiative efficiency (0.36 W m(-2)·ppbv(-1)) with the relatively short lifetime of HFC-1447fz (ca. 8 days) implies that its global warming potential at a time horizon of 100 year is negligible (0.19) compared to that of HCFC-141b (782) and to that of modern foam-expansion blowing agents (148, 882, and 804 for HFC-152a, HFC-245fa and HFC-365mfc, respectively).

  11. Monitoring Abortive Initiation

    PubMed Central

    Hsu, Lilian M.

    2009-01-01

    Abortive initiation, when first discovered, was an enigmatic phenomenon, but fully three decades hence, it has been shown to be an integral step in the transcript initiation process intimately tied to the promoter escape reaction undergone by RNA polymerase at the initiation-elongation transition. A detailed understanding of abortive initiation-promoter escape has brought within reach a full description of the transcription initiation mechanism. This enormous progress was the result of convergent biochemical, genetic, and biophysical investigations propelled by parallel advances in quantitation technology. This chapter discusses the knowledge gained through the biochemical approach and a high-resolution method that yields quantitative and qualitative information regarding abortive initiation-promoter escape at a promoter. PMID:18948204

  12. Incidentalomas: initial management.

    PubMed

    Hitzeman, Nathan; Cotton, Erin

    2014-12-01

    Incidentalomas are increasingly common findings on radiologic studies, causing worry for physicians and patients. Physicians should consider the risk of discovering incidentalomas when contemplating imaging. Patients may assume that incidentalomas are cancer, and may not be aware of the radiation risks associated with repeat imaging. Once incidentalomas are detected, appropriate management is dependent on an informed patient's wishes and the clinical situation. Guidelines are provided for the initial management of eight incidentalomas (pituitary, thyroid, pulmonary, hepatic, pancreatic, adrenal, renal, and ovarian). Patients presenting with pituitary incidentalomas should undergo pituitary-specific magnetic resonance imaging if the lesion is 1 cm or larger, or if it abuts the optic chiasm. Thyroid incidentalomas are ubiquitous, but nodules larger than 1 to 2 cm are of greater concern. Worrisome pulmonary incidentalomas are those larger than 8 mm or those with irregular borders, eccentric calcifications, or low density. However, current guidelines recommend that even pulmonary incidentalomas as small as 4 mm be followed. Solid hepatic incidentalomas 5 mm or larger should be monitored closely, and multiphasic scanning is helpful. Pancreatic cystic neoplasms have malignant potential, and surgery is recommended for pancreatic cysts larger than 3 cm with suspicious features. Adrenal lesions larger than 4 cm are usually biopsied. The Bosniak classification is a well-accepted means of triaging renal incidentalomas. Lesions at category IIF or greater require serial monitoring or surgery. Benign or probably benign ovarian cysts 3 cm or smaller in premenopausal women or 1 cm or smaller in postmenopausal women do not require follow-up. Ovarian cysts with thickened walls or septa, or solid components with blood flow, should be managed closely.

  13. Breckinridge Project, initial effort

    SciTech Connect

    1982-01-01

    This report presents an overview of the Breckinridge Project and summarizes the results achieved during the development phase of the project performed under a Cooperative Agreement with the United States Department of Energy. The Breckinridge Project provides for the design, construction and operation of a 50,000 barrel per day coal liquefaction facility in Breckinridge County, Kentucky. The development of the basic technology used in the Breckinridge Project dates back to the late 1950's and the invention by Hydrocarbon Research, Inc., (HRI) of the ebullated-bed reactor and the H-OIL process. The H-COAL process is based on the H-OIL technology. This coal liquefaction process produces clean low-sulfur petroleum substitutes suitable for most types of hydrocarbon-based fuel and chemical uses regardless of the sulfur content of the coal. A large H-COAL Pilot Plant in operation at Catlettsburg, Kentucky, is converting 220 tons of coal per day into 600 barrels of distillate products by catalytic hydrogenation. The estimated capital cost of the commercial facility is $3.17 billion, and the associated out-of-pocket operating cost is $18 per barrel, both in January 1981 dollars. Financial analysis shows the project to be an attractive investment under certain leveraged conditions which are possible through the assistance of the Synthetic Fuels Corporation. Ashland Synthetic Fuels, Inc. is currently working with the Synthetic Fuels Corporation and potential partners to develop financing for the commercial venture. Critical permits are being obtained and an Environmental Impact Statement is being prepared pursuant to initiating site preparation in early 1983. Commercial operations are expected to start up in early 1988.

  14. Initial Radionuclide Inventories

    SciTech Connect

    H. Miller

    2004-09-19

    The purpose of this analysis is to provide an initial radionuclide inventory (in grams per waste package) and associated uncertainty distributions for use in the Total System Performance Assessment for the License Application (TSPA-LA) in support of the license application for the repository at Yucca Mountain, Nevada. This document is intended for use in postclosure analysis only. Bounding waste stream information and data were collected that capture probable limits. For commercially generated waste, this analysis considers alternative waste stream projections to bound the characteristics of wastes likely to be encountered using arrival scenarios that potentially impact the commercial spent nuclear fuel (CSNF) waste stream. For TSPA-LA, this radionuclide inventory analysis considers U.S. Department of Energy (DOE) high-level radioactive waste (DHLW) glass and two types of spent nuclear fuel (SNF): CSNF and DOE-owned (DSNF). These wastes are placed in two groups of waste packages: the CSNF waste package and the codisposal waste package (CDSP), which are designated to contain DHLW glass and DSNF, or DHLW glass only. The radionuclide inventory for naval SNF is provided separately in the classified ''Naval Nuclear Propulsion Program Technical Support Document'' for the License Application. As noted previously, the radionuclide inventory data presented here is intended only for TSPA-LA postclosure calculations. It is not applicable to preclosure safety calculations. Safe storage, transportation, and ultimate disposal of these wastes require safety analyses to support the design and licensing of repository equipment and facilities. These analyses will require radionuclide inventories to represent the radioactive source term that must be accommodated during handling, storage and disposition of these wastes. This analysis uses the best available information to identify the radionuclide inventory that is expected at the last year of last emplacement, currently identified as

  15. Prioritizing Scientific Initiatives.

    ERIC Educational Resources Information Center

    Bahcall, John N.

    1991-01-01

    Discussed is the way in which a limited number of astronomy research initiatives were chosen and prioritized based on a consensus of members from the Astronomy and Astrophysics Survey Committee. A list of recommended equipment initiatives and estimated costs is provided. (KR)

  16. Prioritizing Scientific Initiatives.

    ERIC Educational Resources Information Center

    Bahcall, John N.

    1991-01-01

    Discussed is the way in which a limited number of astronomy research initiatives were chosen and prioritized based on a consensus of members from the Astronomy and Astrophysics Survey Committee. A list of recommended equipment initiatives and estimated costs is provided. (KR)

  17. The Fostering Hope Initiative

    ERIC Educational Resources Information Center

    Rider, Steven; Winters, Katie; Dean, Joyce; Seymour, Jim

    2014-01-01

    The Fostering Hope Initiative is a neighborhood-based Collective Impact initiative that promotes optimum child and youth development by supporting vulnerable families, encouraging connections between neighbors, strengthening systems to ensure collective impact, and advocating for family-friendly public policy. This article describes the…

  18. Community Marriage Initiatives

    ERIC Educational Resources Information Center

    Doherty, William J.; Anderson, Jared R.

    2004-01-01

    This article reviews the development of community marriage initiatives and their relationship with family professionals, with particular emphasis on sociohistorical context. We describe five leading community marriage initiatives, discuss the state of the evaluation research, and propose new directions for this promising area of work.

  19. Software Architecture Technology Initiative

    DTIC Science & Technology

    2007-05-01

    2007 Carnegie Mellon University Software Architecture Technology Initiative Mark Klein Third Annual SATURN Workshop May 2007 Report Documentation...3. DATES COVERED 00-00-2007 to 00-00-2007 4. TITLE AND SUBTITLE Software Architecture Technology Initiative 5a. CONTRACT NUMBER 5b. GRANT...STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES presented at the SEI Software Architecture Technology User

  20. The Fostering Hope Initiative

    ERIC Educational Resources Information Center

    Rider, Steven; Winters, Katie; Dean, Joyce; Seymour, Jim

    2014-01-01

    The Fostering Hope Initiative is a neighborhood-based Collective Impact initiative that promotes optimum child and youth development by supporting vulnerable families, encouraging connections between neighbors, strengthening systems to ensure collective impact, and advocating for family-friendly public policy. This article describes the…

  1. Winning with Initiative

    ERIC Educational Resources Information Center

    Morgan, Matthew J.

    2004-01-01

    A common complaint among high school coaches is the lack of initiative shown by some of their players. Coaches expect a certain level of decision-making and independence, and more so from team captains and senior players. Developing leadership skills is a major benefit to athletes who participate at a competitive level, and taking initiative can…

  2. Analysis of the effect of initial conditions on the initial development of a turbulent jet

    NASA Technical Reports Server (NTRS)

    Kim, Soong KI; Chung, Myung Kyoon; Cho, Ji Ryong

    1992-01-01

    The effect of the initial condition at the jet exit on the downstream evolution, particularly within the potential core length, were numerically investigated as well as with available experimental data. In order to select the most dependable computational model for the present numerical experiment, a comparative study has been performed with different turbulence models at k-epsilon level, and it was found that the k-epsilon-gammma model yields superior prediction accuracy over other conventional models. The calculated results show that the potential core length and the spreading rate the initial mixing layer are dependent on the initial length scale as well as the turbulent kinetic energy at the jet exit. Such effect of the initial length scale increases with higher initial turbulence level. An empirical parameter has been devised to collapse the calculated data of the potential core length and the spreading rate with various initial conditions onto a single curve.

  3. Synthesis of two potential NK1-receptor ligands using [1-11C]ethyl iodide and [1-11C]propyl iodide and initial PET-imaging.

    PubMed

    Syvänen, Stina; Eriksson, Jonas; Genchel, Tove; Lindhe, Orjan; Antoni, Gunnar; Långström, Bengt

    2007-07-30

    The previously validated NK1-receptor ligand [O-methyl-11C]GR205171 binds with a high affinity to the NK1-receptor and displays a slow dissociation from the receptor. Hence, it cannot be used in vivo for detecting concentration changes in substance P, the endogenous ligand for the NK1-receptor. A radioligand used for monitoring these changes has to enable displacement by the endogenous ligand and thus bind reversibly to the receptor. Small changes in the structure of a receptor ligand can lead to changes in binding characteristics and also in the ability to penetrate the blood-brain barrier. The aim of this study was to use carbon-11 labelled ethyl and propyl iodide with high specific radioactivity in the synthesis of two new and potentially reversible NK1-receptor ligands with chemical structures based on [O-methyl-11C]GR205171. [1-11C]Ethyl and [1-11C]propyl iodide with specific radioactivities of 90 GBq/mumol and 270 GBq/mumol, respectively, were used in the synthesis of [O-methyl-11C]GR205171 analogues by alkylation of O-desmethyl GR205171. The brain uptake of the obtained (2S,3S)-N-(1-(2- [1-11C]ethoxy-5-(3-(trifluoromethyl)-4H-1,2,4-triazol-4-yl)phenyl)ethyl)-2-phenylpiperidin-3-amine (I) and (2S,3S)-2-phenyl-N-(1-(2- [1-11C]propoxy-5-(3-(trifluoromethyl)-4H-1,2,4-triazol-4-yl)phenyl)ethyl)piperidin-3-amine (II) was studied with PET in guinea pigs and rhesus monkeys and compared to the uptake of [O-methyl-11C]GR205171. All ligands had similar uptake distribution in the guinea pig brain. The PET-studies in rhesus monkeys showed that (II) had no specific binding in striatum. Ligand (I) had moderate specific binding compared to the [O-methyl-11C]GR205171. The ethyl analogue (I) displayed reversible binding characteristics contrary to the slow dissociation rate shown by [O-methyl-11C]GR205171. The propyl-analogue (II) cannot be used for detecting changes in NK1-ligand levels, while further studies should be performed with the ethyl-analogue (I).

  4. Synthesis of two potential NK1-receptor ligands using [1-11C]ethyl iodide and [1-11C]propyl iodide and initial PET-imaging

    PubMed Central

    Syvänen, Stina; Eriksson, Jonas; Genchel, Tove; Lindhe, Örjan; Antoni, Gunnar; Långström, Bengt

    2007-01-01

    Background The previously validated NK1-receptor ligand [O-methyl-11C]GR205171 binds with a high affinity to the NK1-receptor and displays a slow dissociation from the receptor. Hence, it cannot be used in vivo for detecting concentration changes in substance P, the endogenous ligand for the NK1-receptor. A radioligand used for monitoring these changes has to enable displacement by the endogenous ligand and thus bind reversibly to the receptor. Small changes in the structure of a receptor ligand can lead to changes in binding characteristics and also in the ability to penetrate the blood-brain barrier. The aim of this study was to use carbon-11 labelled ethyl and propyl iodide with high specific radioactivity in the synthesis of two new and potentially reversible NK1-receptor ligands with chemical structures based on [O-methyl-11C]GR205171. Methods [1-11C]Ethyl and [1-11C]propyl iodide with specific radioactivities of 90 GBq/μmol and 270 GBq/μmol, respectively, were used in the synthesis of [O-methyl-11C]GR205171 analogues by alkylation of O-desmethyl GR205171. The brain uptake of the obtained (2S,3S)-N-(1-(2- [1-11C]ethoxy-5-(3-(trifluoromethyl)-4H-1,2,4-triazol-4-yl)phenyl)ethyl)-2-phenylpiperidin-3-amine (I) and (2S,3S)-2-phenyl-N-(1-(2- [1-11C]propoxy-5-(3-(trifluoromethyl)-4H-1,2,4-triazol-4-yl)phenyl)ethyl)piperidin-3-amine (II) was studied with PET in guinea pigs and rhesus monkeys and compared to the uptake of [O-methyl-11C]GR205171. Results All ligands had similar uptake distribution in the guinea pig brain. The PET-studies in rhesus monkeys showed that (II) had no specific binding in striatum. Ligand (I) had moderate specific binding compared to the [O-methyl-11C]GR205171. The ethyl analogue (I) displayed reversible binding characteristics contrary to the slow dissociation rate shown by [O-methyl-11C]GR205171. Conclusion The propyl-analogue (II) cannot be used for detecting changes in NK1-ligand levels, while further studies should be performed with the

  5. DICE: Disk Initial Conditions Environment

    NASA Astrophysics Data System (ADS)

    Perret, Valentin

    2016-07-01

    DICE models initial conditions of idealized galaxies to study their secular evolution or their more complex interactions such as mergers or compact groups using N-Body/hydro codes. The code can set up a large number of components modeling distinct parts of the galaxy, and creates 3D distributions of particles using a N-try MCMC algorithm which does not require a prior knowledge of the distribution function. The gravitational potential is then computed on a multi-level Cartesian mesh by solving the Poisson equation in the Fourier space. Finally, the dynamical equilibrium of each component is computed by integrating the Jeans equations for each particles. Several galaxies can be generated in a row and be placed on Keplerian orbits to model interactions. DICE writes the initial conditions in the Gadget1 or Gadget2 (ascl:0003.001) format and is fully compatible with Ramses (ascl:1011.007).

  6. The national geomagnetic initiative

    NASA Astrophysics Data System (ADS)

    The Earth's magnetic field, through its variability over a spectrum of spatial and temporal scales, contains fundamental information on the solid Earth and geospace environment (the latter comprising the atmosphere, ionosphere, and magnetosphere). Integrated studies of the geomagnetic field have the potential to address a wide range of important processes in the deep mantle and core, asthenosphere, lithosphere, oceans, and the solar-terrestrial environment. These studies have direct applications to important societal problems, including resource assessment and exploration, natural hazard mitigation, safe navigation, and the maintenance and survivability of communications and power systems on the ground and in space. Studies of the Earth's magnetic field are supported by a variety of federal and state agencies as well as by private industry. Both basic and applied research is presently supported by several federal agencies, including the National Science Foundation (NSF), U.S. Geological Survey (USGS), U.S. Department of Energy (DOE), National Oceanic and Atmospheric Administration (NOAA), National Aeronautics and Space Administration (NASA), and U.S. Department of Defense (DOD) (through the Navy, Air Force, and Defense Mapping Agency). Although each agency has a unique, well-defined mission in geomagnetic studies, many areas of interest overlap. For example, NASA, the Navy, and USGS collaborate closely in the development of main field reference models. NASA, NSF, and the Air Force collaborate in space physics. These interagency linkages need to be strengthened. Over the past decade, new opportunities for fundamental advances in geomagnetic research have emerged as a result of three factors: well-posed, first-order scientific questions; increased interrelation of research activities dealing with geomagnetic phenomena; and recent developments in technology. These new opportunities can be exploited through a national geomagnetic initiative to define objectives and

  7. The national geomagnetic initiative

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The Earth's magnetic field, through its variability over a spectrum of spatial and temporal scales, contains fundamental information on the solid Earth and geospace environment (the latter comprising the atmosphere, ionosphere, and magnetosphere). Integrated studies of the geomagnetic field have the potential to address a wide range of important processes in the deep mantle and core, asthenosphere, lithosphere, oceans, and the solar-terrestrial environment. These studies have direct applications to important societal problems, including resource assessment and exploration, natural hazard mitigation, safe navigation, and the maintenance and survivability of communications and power systems on the ground and in space. Studies of the Earth's magnetic field are supported by a variety of federal and state agencies as well as by private industry. Both basic and applied research is presently supported by several federal agencies, including the National Science Foundation (NSF), U.S. Geological Survey (USGS), U.S. Department of Energy (DOE), National Oceanic and Atmospheric Administration (NOAA), National Aeronautics and Space Administration (NASA), and U.S. Department of Defense (DOD) (through the Navy, Air Force, and Defense Mapping Agency). Although each agency has a unique, well-defined mission in geomagnetic studies, many areas of interest overlap. For example, NASA, the Navy, and USGS collaborate closely in the development of main field reference models. NASA, NSF, and the Air Force collaborate in space physics. These interagency linkages need to be strengthened. Over the past decade, new opportunities for fundamental advances in geomagnetic research have emerged as a result of three factors: well-posed, first-order scientific questions; increased interrelation of research activities dealing with geomagnetic phenomena; and recent developments in technology. These new opportunities can be exploited through a national geomagnetic initiative to define objectives and

  8. Autonomous aircraft initiative study

    NASA Technical Reports Server (NTRS)

    Hewett, Marle D.

    1991-01-01

    The results of a consulting effort to aid NASA Ames-Dryden in defining a new initiative in aircraft automation are described. The initiative described is a multi-year, multi-center technology development and flight demonstration program. The initiative features the further development of technologies in aircraft automation already being pursued at multiple NASA centers and Department of Defense (DoD) research and Development (R and D) facilities. The proposed initiative involves the development of technologies in intelligent systems, guidance, control, software development, airborne computing, navigation, communications, sensors, unmanned vehicles, and air traffic control. It involves the integration and implementation of these technologies to the extent necessary to conduct selected and incremental flight demonstrations.

  9. RAS Initiative - Events

    Cancer.gov

    The NCI RAS Initiative has organized multiple events with outside experts to discuss how the latest scientific and technological breakthroughs can be applied to discover vulnerabilities in RAS-driven cancers.

  10. About the RAS Initiative

    Cancer.gov

    The RAS Initiative, a "hub and spoke" model, connects researchers to better understand and target the more than 30% of cancers driven by mutations in RAS genes. Includes oversight and contact information.

  11. RAS Initiative - Community Outreach

    Cancer.gov

    Through community and technical collaborations, workshops and symposia, and the distribution of reference reagents, the RAS Initiative seeks to increase the sharing of knowledge and resources essential to defeating cancers caused by mutant RAS genes.

  12. Project Matching Initiative

    EPA Pesticide Factsheets

    The Green Power Partnership's Project Matching initiative works to connect green power users with new, not-yet-built renewable energy projects that may align with their energy, environmental, and financial objectives.

  13. Advanced Concepts Research Initiative

    EPA Science Inventory

    This initiative is investigating various approaches to controlling and treating wet-weather flow (WWF) discharges in the urban watershed. WWF, including combined sewer overflow (CSO), sanitary sewer overflow (SSO) and stormwater discharges are leading causes of receiving water q...

  14. Advanced Concepts Research Initiative

    EPA Science Inventory

    This initiative is investigating various approaches to controlling and treating wet-weather flow (WWF) discharges in the urban watershed. WWF, including combined sewer overflow (CSO), sanitary sewer overflow (SSO) and stormwater discharges are leading causes of receiving water q...

  15. The RAS Initiative

    Cancer.gov

    NCI established the RAS Initiative to explore innovative approaches for attacking the proteins encoded by mutant forms of RAS genes and to ultimately create effective, new therapies for RAS-related cancers.

  16. Collaborative Procurement Initiative

    EPA Pesticide Factsheets

    GPP's Clean Energy Collaborative Procurement Initiative provides a platform for deploying clean energy technologies across multiple government and educational organizations for maximum impact on installed solar system capacity and local economic activity.

  17. Midwest Clean Diesel Initiative

    EPA Pesticide Factsheets

    The Midwest Clean Diesel Initiative (MCDI) is a collaboration of federal, state and local agencies, along with communities, non-profit organizations and private companies working together by reducing exposure to emissions from diesel engines

  18. PESP Landscaping Initiative

    EPA Pesticide Factsheets

    Landscaping practices can positively or negatively affect local environments and human health. The Landscaping Initiative seeks to enhance benefits of landscaping while reducing need for pesticides, fertilizers, etc., by working with partners.

  19. Piezoelectrically Initiated Pyrotechnic Igniter

    NASA Technical Reports Server (NTRS)

    Quince, Asia; Dutton, Maureen; Hicks, Robert; Burnham, Karen

    2013-01-01

    This innovation consists of a pyrotechnic initiator and piezoelectric initiation system. The device will be capable of being initiated mechanically; resisting initiation by EMF, RF, and EMI (electromagnetic field, radio frequency, and electromagnetic interference, respectively); and initiating in water environments and space environments. Current devices of this nature are initiated by the mechanical action of a firing pin against a primer. Primers historically are prone to failure. These failures are commonly known as misfires or hang-fires. In many cases, the primer shows the dent where the firing pin struck the primer, but the primer failed to fire. In devices such as "T" handles, which are commonly used to initiate the blowout of canopies, loss of function of the device may result in loss of crew. In devices such as flares or smoke generators, failure can result in failure to spot a downed pilot. The piezoelectrically initiated ignition system consists of a pyrotechnic device that plugs into a mechanical system (activator), which on activation, generates a high-voltage spark. The activator, when released, will strike a stack of electrically linked piezo crystals, generating a high-voltage, low-amperage current that is then conducted to the pyro-initiator. Within the initiator, an electrode releases a spark that passes through a pyrotechnic first-fire mixture, causing it to combust. The combustion of the first-fire initiates a primary pyrotechnic or explosive powder. If used in a "T" handle, the primary would ramp the speed of burn up to the speed of sound, generating a shock wave that would cause a high explosive to go "high order." In a flare or smoke generator, the secondary would produce the heat necessary to ignite the pyrotechnic mixture. The piezo activator subsystem is redundant in that a second stack of crystals would be struck at the same time with the same activation force, doubling the probability of a first strike spark generation. If the first

  20. Software Architecture Technology Initiative

    DTIC Science & Technology

    2008-04-01

    2008 Carnegie Mellon University 2008 PLS March 2008 © 2008 Carnegie Mellon University Software Architecture Technology Initiative SATURN 2008...SUBTITLE Software Architecture Technology Initiative 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...SUPPLEMENTARY NOTES presented at the SEI Software Architecture Technology User Network (SATURN) Workshop, 30 Apr ? 1 May 2008, Pittsburgh, PA. 14

  1. National Plant Genome Initiative

    DTIC Science & Technology

    2005-01-01

    JAN 2005 2. REPORT TYPE 3. DATES COVERED 00-00-2005 to 00-00-2005 4. TITLE AND SUBTITLE National Plant Genome Initiative. Progress Report 5a...refl ected in future Administration budgets. Cover Photo: National Plant Genome Initiative Progress Report January 2005 National Science and...Technology Council Committee on Science Interagency Working Group on Plant Genomes [Blank Page] Interagency Working Group on Plant Genomes Committee on

  2. Pre-Feasibility Analysis of Pellet Manufacturing on the Former Loring Air Force Base Site. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    SciTech Connect

    Hunsberger, R.; Mosey, G.

    2014-04-01

    The U.S. Environmental Protection Agency (EPA) Office of Solid Waste and Emergency Response, in accordance with the RE-Powering America's Lands initiative, engaged the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to conduct feasibility studies to assess the viability of developing renewable energy generating facilities on contaminated sites. This site, in Limestone, Maine -- formerly the location of the Loring Air Force Base but now owned by the Aroostook Band of Micmac -- was selected for the potential to produce heating pellets from woody feedstock. Biomass was chosen as the renewable energy resource to evaluate based on abundant woody-biomass resources available in the area. NREL also evaluates potential savings from converting existing Micmac property from oil-fired heating to pellet heating.

  3. Optimal flight initiation distance.

    PubMed

    Cooper, William E; Frederick, William G

    2007-01-07

    Decisions regarding flight initiation distance have received scant theoretical attention. A graphical model by Ydenberg and Dill (1986. The economics of fleeing from predators. Adv. Stud. Behav. 16, 229-249) that has guided research for the past 20 years specifies when escape begins. In the model, a prey detects a predator, monitors its approach until costs of escape and of remaining are equal, and then flees. The distance between predator and prey when escape is initiated (approach distance = flight initiation distance) occurs where decreasing cost of remaining and increasing cost of fleeing intersect. We argue that prey fleeing as predicted cannot maximize fitness because the best prey can do is break even during an encounter. We develop two optimality models, one applying when all expected future contribution to fitness (residual reproductive value) is lost if the prey dies, the other when any fitness gained (increase in expected RRV) during the encounter is retained after death. Both models predict optimal flight initiation distance from initial expected fitness, benefits obtainable during encounters, costs of escaping, and probability of being killed. Predictions match extensively verified predictions of Ydenberg and Dill's (1986) model. Our main conclusion is that optimality models are preferable to break-even models because they permit fitness maximization, offer many new testable predictions, and allow assessment of prey decisions in many naturally occurring situations through modification of benefit, escape cost, and risk functions.

  4. Tapping America's Potential: The Education for Innovation Initiative

    ERIC Educational Resources Information Center

    Business Roundtable, 2005

    2005-01-01

    This document examines the need to reform education in America. The goal of the United States is to double the number of science, technology, engineering and mathematics graduates with bachelor's degrees by 2015. A core set of recommendations are reviewed: (1) Build public support for making science, technology, engineering and math improvement a…

  5. An Evaluation of Potential Countermeasures to the Strategic Defense Initiative.

    DTIC Science & Technology

    1986-03-01

    intensive effort to define a long term research and development program to achieve our ultimate goal of eliminating the threat posed by strategic...conventional weapons, the deploy- ment of a BMD would greatly increase the risk of conventional war. (5) that the long transition period from a U.S...March 109 16 SLPPLEMENTARY NOTATION 7 COSATI CODES 18 SUBJC.T TERMS (Continue on reverse if necessary and identify by block number) rELD GROUP SUB

  6. Assessing of genotoxicity of 16 centralized source-waters in China by means of the SOS/umu assay and the micronucleus test: initial identification of the potential genotoxicants by use of a GC/MS method and the QSAR Toolbox 3.0.

    PubMed

    Ye, Yan; Weiwei, Jiang; Na, Li; Mei, Ma; Donghong, Wang; Zijian, Wang; Kaifeng, Rao

    2014-03-15

    Only few studies were conducted to assess genotoxicity of centralized source waters in China and almost none of them dealt with the causal relationship between the genotoxic effect and genotoxicants. In this work, 16 centralized source waters in China were sampled from five river systems and genotoxicity of their organic extracts was assessed by use of the SOS/umu test for DNA-damaging effect and the miniaturized flow cytometry-based micronucleus (MN) test for chromosome-damaging effect. In addition, initial identification of potential genotoxicants for the six samples from the Yangtze River was done with a GC/MS method and the QSAR toolbox 3.0. The results demonstrate that eight samples showed both indirect and direct DNA-damaging effects, another four samples showed only indirect DNA-damaging effects, while chromosome-damaging effects were found for 14 out of the 16 samples, in which aneugenic and clastogenic modes of action were found for 4 and 10 samples, respectively. Both direct/indirect DNA-damaging effects and chromosome-damaging effects were induced by the six Yangtze River samples, and the existing different types of genotoxicant confirmed the results. Furthermore, o-phenylphenol was initially identified as the major cause for the DNA-damaging effects while PAHs, pesticides, phenol and anthraquinone were identified as ubiquitous chromosome-damaging agents among these samples. In conclusion, a combination of the SOS/umu test and the miniaturized flow cytometry-based MN test to detect both DNA-damaging and chromosome-damaging effects could be used as a comprehensive genotoxicity assessment tool for the evaluation and classification of genotoxicity of complex mixtures, and potential genotoxicants can be initially identified with additional information from chemical analysis and the QSAR toolbox.

  7. STI Program Multimedia Initiative

    NASA Technical Reports Server (NTRS)

    Cotter, Gladys A.; Kaye, Karen

    1993-01-01

    This paper relates the experience of the NASA Scientific and Technical Information Program in introducing multimedia within the STI Program framework. A discussion of multimedia technology is included to provide context for the STI Program effort. The STI Program's Multimedia Initiative is discussed in detail. Parallels and differences between multimedia and traditional information systems project development are highlighted. Challenges faced by the program in initiating its multimedia project are summarized along with lessons learned. The paper concludes with a synopsis of the benefits the program hopes to provide its users through the introduction of multimedia illustrated by examples of successful multimedia projects.

  8. Civil space technology initiative

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Civil Space Technology Initiative (CSTI) is a major, focused, space technology program of the Office of Aeronautics, Exploration and Technology (OAET) of NASA. The program was initiated to advance technology beyond basic research in order to expand and enhance system and vehicle capabilities for near-term missions. CSTI takes critical technologies to the point at which a user can confidently incorporate the new or expanded capabilities into relatively near-term, high-priority NASA missions. In particular, the CSTI program emphasizes technologies necessary for reliable and efficient access to and operation in Earth orbit as well as for support of scientific missions from Earth orbit.

  9. Shock initiation of nitromethane

    SciTech Connect

    Yoo, C.S.; Holmes, N.C.

    1993-12-31

    The shock initiation processes of nitromethane have been examined by using a fast time-resolved emission spectroscopy at a two-stage gas gun. a broad, but strong emission has been observed in a spectral range between 350 and 700 nm from shocked nitromethane above 9 GPa. The temporal profile suggests that shocked nitromethane detonates through three characteristic periods, namely an induction period, a hock initiation period, and a thermal explosion period. This paper discusses temporal and chemical characteristics of these periods and present the temperature of the shock-detonating nitromethane at pressures between 9 and 15 GPa.

  10. Statistical initial orbit determination

    SciTech Connect

    Taff, L.G.; Belkin, B.; Schweiter, G.A.; Sommar, K. D.H. Wagner Associates, Inc., Paoli, PA )

    1992-02-01

    For the ballistic missile initial orbit determination problem in particular, the concept of 'launch folders' is extended. This allows to decouple the observational data from the initial orbit determination problem per se. The observational data is only used to select among the possible orbital element sets in the group of folders. Monte Carlo simulations using up to 7200 orbital element sets are described. The results are compared to the true orbital element set and the one a good radar would have been able to produce if collocated with the optical sensor. The simplest version of the new method routinely outperforms the radar initial orbital element set by a factor of two in future miss distance. In addition, not only can a differentially corrected orbital element set be produced via this approach - after only two measurements of direction - but also an updated, meaningful, six-dimensional covariance array for it can be calculated. This technique represents a significant advance in initial orbit determination for this problem, and the concept can easily be extended to minor planets and artificial satellites. 9 refs.

  11. The SEED Initiative

    ERIC Educational Resources Information Center

    Teich, Carolyn R.

    2011-01-01

    Committed to fulfilling the promise of the green economy, the American Association of Community Colleges (AACC) launched the Sustainability Education and Economic Development (SEED) initiative (www.theseedcenter.org) in October 2010. The project advances sustainability and clean energy workforce development practices at community colleges by…

  12. Department-Initiated Change

    ERIC Educational Resources Information Center

    Watson, Anne; De Geest, Els

    2014-01-01

    This paper reports the activity of three secondary school mathematics departments in England in self-initiated states of change that led to overall improvements in students' achievements when compared to previous cohorts. This took place without intervention and without their participation in external projects. They provide examples of departments…

  13. Monolithic exploding foil initiator

    DOEpatents

    Welle, Eric J; Vianco, Paul T; Headley, Paul S; Jarrell, Jason A; Garrity, J. Emmett; Shelton, Keegan P; Marley, Stephen K

    2012-10-23

    A monolithic exploding foil initiator (EFI) or slapper detonator and the method for making the monolithic EFI wherein the exploding bridge and the dielectric from which the flyer will be generated are integrated directly onto the header. In some embodiments, the barrel is directly integrated directly onto the header.

  14. Strategic Defense Initiative program

    SciTech Connect

    Conachan, F.C.

    1991-05-01

    This paper discusses the Strategic Defense Initiative (SDI) program. It summarizes the major programmatic and technological lessons learned from the SDI program over the past 7 years. It provides information on: past uses of SDI funds, persistent optimism in planning and starting projects, evolution of SDI architecture, and accuracy of cost estimates.

  15. Best Practices & Outstanding Initiatives

    ERIC Educational Resources Information Center

    Training, 2011

    2011-01-01

    In this article, "Training" editors recognize innovative and successful learning and development programs and practices. They share best practices from Automatic Data Processing, Inc., Farmers Insurance Group, FedEx Express, InterContinental Hotels Group, and Oakwood Temporary Housing. They also present the outstanding initiatives of EMD Serono,…

  16. Sourcebook of Restructuring Initiatives.

    ERIC Educational Resources Information Center

    Stefkovich, Jacqueline A., Ed.

    This three-part sourcebook identifies school restructuring initiatives with a national scope and presents comprehensive information about them. Part 1 identifies and describes national restructuring programs (e.g., Coalition of Essential Schools, Learning Tomorrow, Success for All). Each program description provides an overview of the program as…

  17. Transformative Change Initiative

    ERIC Educational Resources Information Center

    Bragg, D. D.; Kirby, C.; Witt, M. A.; Richie, D.; Mix, S.; Feldbaum, M.; Liu, S.; Mason, M.

    2014-01-01

    The Transformative Change Initiative (TCI) is dedicated to assisting community colleges to scale up innovation in the form of guided pathways, programs of study, and evidence-based strategies to improve student outcomes and program, organization, and system performance. The impetus for TCI is the Trade Adjustment Assistance Community College and…

  18. Clean Energy Manufacturing Initiative

    SciTech Connect

    2013-04-01

    The initiative will strategically focus and rally EERE’s clean energy technology offices and Advanced Manufacturing Office around the urgent competitive opportunity for the United States to be the leader in the clean energy manufacturing industries and jobs of today and tomorrow.

  19. Envisioning Effective Laptop Initiatives

    ERIC Educational Resources Information Center

    Clausen, Jon M.; Britten, Jody; Ring, Gail

    2008-01-01

    A recent survey of 74 building-level school administrators in Indiana challenged many of the assumptions regarding 1:1 laptop initiatives and how 1:1 access would affect teaching and learning. It also revealed disturbing realities regarding instructional practices of teachers, as well as efforts to improve school technology integration. The intent…

  20. Kinesthetic Initial Training.

    ERIC Educational Resources Information Center

    Ostrom, Gladys

    1978-01-01

    The author's plans for Kinesthetic Initial Training (KIT), a system of interrelated subjects designed to teach handicapped and gifted students basic reading, writing, arithmetic, and grammar skills through the use of concrete materials, are described. KIT components are reviewed, and implications are considered for areas of psychomotor,…

  1. Best Practices & Outstanding Initiatives

    ERIC Educational Resources Information Center

    Training, 2011

    2011-01-01

    In this article, "Training" editors recognize innovative and successful learning and development programs and practices. They share best practices from Automatic Data Processing, Inc., Farmers Insurance Group, FedEx Express, InterContinental Hotels Group, and Oakwood Temporary Housing. They also present the outstanding initiatives of EMD Serono,…

  2. Department-Initiated Change

    ERIC Educational Resources Information Center

    Watson, Anne; De Geest, Els

    2014-01-01

    This paper reports the activity of three secondary school mathematics departments in England in self-initiated states of change that led to overall improvements in students' achievements when compared to previous cohorts. This took place without intervention and without their participation in external projects. They provide examples of departments…

  3. Information Technology Initiative (Videorecording),

    DTIC Science & Technology

    Physical description: 1 VHS video; col.; sd.; mono.; standard playback sp.; 35:40 mins.; 1/2 in. In this video, Dr. Kurt Fisher, Deputy Director for Information Technology , introduces the Corporate Information Management (CIM) program and explains the following major technical initiatives: reuse/repositories; I-case; data administration; information technology architecture; software process improvement; standards.

  4. Mixed-Initiative Clustering

    ERIC Educational Resources Information Center

    Huang, Yifen

    2010-01-01

    Mixed-initiative clustering is a task where a user and a machine work collaboratively to analyze a large set of documents. We hypothesize that a user and a machine can both learn better clustering models through enriched communication and interactive learning from each other. The first contribution or this thesis is providing a framework of…

  5. Mixed-Initiative Clustering

    ERIC Educational Resources Information Center

    Huang, Yifen

    2010-01-01

    Mixed-initiative clustering is a task where a user and a machine work collaboratively to analyze a large set of documents. We hypothesize that a user and a machine can both learn better clustering models through enriched communication and interactive learning from each other. The first contribution or this thesis is providing a framework of…

  6. Ontario's Student Voice Initiative

    ERIC Educational Resources Information Center

    Courtney, Jean

    2014-01-01

    This article describes in some detail aspects of the Student Voice initiative funded and championed by Ontario's Ministry of Education since 2008. The project enables thousands of students to make their voices heard in meaningful ways and to participate in student-led research. Some students from grades 7 to 12 become members of the Student…

  7. Initial Teaching Orthographies.

    ERIC Educational Resources Information Center

    Dewey, Godfrey

    To achieve its purpose, an initial teaching orthography (i.t.o.) should be as simple in form and substance as possible; it should be phonemic rather than phonetic. The 40 sounds distinguished by Pitmanic shorthand and some provision for schwa can serve as a basic code. The symbols can be derived from either of two major sources--standardizing the…

  8. Focusing educational initiatives

    NASA Technical Reports Server (NTRS)

    Parks, George K.

    1990-01-01

    The United States will soon be facing a critical shortage of aerospace scientists and engineers. To address this problem, Space Grant Colleges can assist in focusing interest in existing educational initiatives and in creating new educational opportunities, particularly for women and underrepresented minorities.

  9. America's Caribbean Basin Initiative.

    ERIC Educational Resources Information Center

    Kasten, Robert W.

    1983-01-01

    Nearly all of the countries that have succeeded in their development over the past 30 years have done so on the strength of market-oriented policies and vigorous participation in the international economy. Aid must be complemented by trade and investment. The Caribbean Basin Initiative puts these principles into practice. (RM)

  10. Next generation initiation techniques

    NASA Technical Reports Server (NTRS)

    Warner, Tom; Derber, John; Zupanski, Milija; Cohn, Steve; Verlinde, Hans

    1993-01-01

    Four-dimensional data assimilation strategies can generally be classified as either current or next generation, depending upon whether they are used operationally or not. Current-generation data-assimilation techniques are those that are presently used routinely in operational-forecasting or research applications. They can be classified into the following categories: intermittent assimilation, Newtonian relaxation, and physical initialization. It should be noted that these techniques are the subject of continued research, and their improvement will parallel the development of next generation techniques described by the other speakers. Next generation assimilation techniques are those that are under development but are not yet used operationally. Most of these procedures are derived from control theory or variational methods and primarily represent continuous assimilation approaches, in which the data and model dynamics are 'fitted' to each other in an optimal way. Another 'next generation' category is the initialization of convective-scale models. Intermittent assimilation systems use an objective analysis to combine all observations within a time window that is centered on the analysis time. Continuous first-generation assimilation systems are usually based on the Newtonian-relaxation or 'nudging' techniques. Physical initialization procedures generally involve the use of standard or nonstandard data to force some physical process in the model during an assimilation period. Under the topic of next-generation assimilation techniques, variational approaches are currently being actively developed. Variational approaches seek to minimize a cost or penalty function which measures a model's fit to observations, background fields and other imposed constraints. Alternatively, the Kalman filter technique, which is also under investigation as a data assimilation procedure for numerical weather prediction, can yield acceptable initial conditions for mesoscale models. The

  11. Naval Station Newport Wind Resource Assessment. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites, and The Naval Facilities Engineering Service Center

    SciTech Connect

    Robichaud, R.; Fields, J.; Roberts, J. O.

    2012-02-01

    The U.S. Environmental Protection Agency (EPA) launched the RE-Powering America's Land initiative to encourage development of renewable energy (RE) on potentially contaminated land and mine sites. EPA is collaborating with the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL) to evaluate RE options at Naval Station (NAVSTA) Newport in Newport, Rhode Island where multiple contaminated areas pose a threat to human health and the environment. Designated a superfund site on the National Priorities List in 1989, the base is committed to working toward reducing the its dependency on fossil fuels, decreasing its carbon footprint, and implementing RE projects where feasible. The Naval Facilities Engineering Service Center (NFESC) partnered with NREL in February 2009 to investigate the potential for wind energy generation at a number of Naval and Marine bases on the East Coast. NAVSTA Newport was one of several bases chosen for a detailed, site-specific wind resource investigation. NAVSTA Newport, in conjunction with NREL and NFESC, has been actively engaged in assessing the wind resource through several ongoing efforts. This report focuses on the wind resource assessment, the estimated energy production of wind turbines, and a survey of potential wind turbine options based upon the site-specific wind resource.

  12. Examining the Potential of Renewable Energy

    SciTech Connect

    Not Available

    2006-09-01

    This outreach document goes to potential partners for NREL's Renewable Energy Potential Initiative, which will explore the long-term potential of Renewable Energy to meet a substantial share of U.S. energy needs.

  13. Oklahoma Healthy Homes initiative.

    PubMed

    Khan, Fahad

    2011-01-01

    Compelling scientific evidence suggests that a strong association exists between housing-related hazards and the health and safety of their residents. Health, safety, and environmental hazards (such as asthma and allergy triggers), unintentional injury hazards, lead-based paint hazards, and poor indoor air quality are interrelated with substandard housing conditions. This article describes a Healthy Homes initiative to address these hazards in a coordinated fashion in the home, rather than taking a categorical approach, even in the presence of multiple hazards. It also provides an overview of Oklahoma's Healthy Homes initiative and its pilot project, the Tulsa Safe and Healthy Housing Project, which is currently administered in Tulsa in collaboration with Children First, Oklahoma's Nurse-Family Partnership program. This pilot project seeks to open new areas of research that can lead to a greater understanding of environmental health issues related to substandard housing in the United States, which will eventually make homes safer and healthier.

  14. The TRANSPLANTEX initiative.

    PubMed

    Bahram, Seiamak; Carapito, Raphael; Gourraud, Pierre-Antoine; Charron, Dominique

    2016-11-01

    TRANSPLANTEX, a French "investment for the future" initiated consortium of leading transplant units and research laboratories across France and a number of European countries aims to unravel, through mainly high-throughput genomics (and other omics) analyses of donor and recipients, novel (a) non-HLA, histocompatibility antigens, whether inside, or outside the MHC; (b) pre/post transplantation biomarkers. This shall lead to our better understanding of the pathophysiology of (and eventually designing better therapeutics for) the graft-versus-host disease in hematopoietic cell transplants and that of chronic graft rejection after kidney transplant. Industrial developments as well as innovative teaching initiatives are also integral part of this program. The present issue of Human Immunology aims to present a first snapshot of some of the research performed by TRANPLANTEX partners. Copyright © 2016. Published by Elsevier Inc.

  15. Antarctic Geoscience Initiative

    NASA Astrophysics Data System (ADS)

    Dalziel, Ian W. D.; Zimmerman, Herman B.

    Antarctia has recently been described as a continent surrounded by advice. The advice stems from growing realization of the Antarctic's importance in many aspects of globalscale Earth science. This article outlines a U.S. and international initiative to move solid-Earth scientists from an advisory role to one of acquiring new data bearing on the structure and evolution of the ice-covered Antarctic lithosphere.The initiative has marine, airborne, and terrestrial components; plans for all three are underway. Platforms exist for undertaking the work at sea and in the air, but land geophysical techniques need to be adapted to the Antarctic environment. An international workshop to plan modern over-ice geoscience transects will be convened in Washington, D.C., July 19-22 in conjunction with the 28th International Geological Congress (IGC).

  16. Gravity wave initiated convection

    NASA Technical Reports Server (NTRS)

    Hung, R. J.

    1990-01-01

    The vertical velocity of convection initiated by gravity waves was investigated. In one particular case, the convective motion-initiated and supported by the gravity wave-induced activity (excluding contributions made by other mechanisms) reached its maximum value about one hour before the production of the funnel clouds. In another case, both rawinsonde and geosynchronous satellite imagery were used to study the life cycles of severe convective storms. Cloud modelling with input sounding data and rapid-scan imagery from GOES were used to investigate storm cloud formation, development and dissipation in terms of growth and collapse of cloud tops, as well as, the life cycles of the penetration of overshooting turrets above the tropopause. The results based on these two approaches are presented and discussed.

  17. COTS Initiative Panel Discussion

    NASA Image and Video Library

    2013-11-13

    Phil McAlister, Director of Commercial Spaceflight Development at NASA, delivers remarks panel discussion on the Commercial Orbital Transportation Services (COTS) initiative at NASA Headquarters in Washington on Wednesday, November 13, 2013. Through COTS, NASA's partners Space Exploration Technologies Corp. (SpaceX) and Orbital Sciences Corp., developed new U.S. rockets and spacecraft, launched from U.S. soil, capable of transporting cargo to low-Earth orbit and the International Space Station. Photo Credit: (NASA/Jay Westcott)

  18. Overview of Explosive Initiators

    DTIC Science & Technology

    2015-11-01

    Primary explosive Initiator Detonator Primer Blasting cap Lead azide Lead styphnate 16. SECURITY CLASSIFICATION OF...Conclusions 13 References 15 Distribution List 17 FIGURES 1 Decomposition reaction of lead azide in the presence of carbon dioxide and water (ref...the world, currently the most popular are lead azide (Pb(N3)2) and lead styphnate (both normal and basic forms) and tetrazene. With its high explosive

  19. The NLM Indexing Initiative.

    PubMed Central

    Aronson, A. R.; Bodenreider, O.; Chang, H. F.; Humphrey, S. M.; Mork, J. G.; Nelson, S. J.; Rindflesch, T. C.; Wilbur, W. J.

    2000-01-01

    The objective of NLM's Indexing Initiative (IND) is to investigate methods whereby automated indexing methods partially or completely substitute for current indexing practices. The project will be considered a success if methods can be designed and implemented that result in retrieval performance that is equal to or better than the retrieval performance of systems based principally on humanly assigned index terms. We describe the current state of the project and discuss our plans for the future. PMID:11079836

  20. The NLM Indexing Initiative.

    PubMed

    Aronson, A R; Bodenreider, O; Chang, H F; Humphrey, S M; Mork, J G; Nelson, S J; Rindflesch, T C; Wilbur, W J

    2000-01-01

    The objective of NLM's Indexing Initiative (IND) is to investigate methods whereby automated indexing methods partially or completely substitute for current indexing practices. The project will be considered a success if methods can be designed and implemented that result in retrieval performance that is equal to or better than the retrieval performance of systems based principally on humanly assigned index terms. We describe the current state of the project and discuss our plans for the future.

  1. Genetics of Fiber Initiation

    USDA-ARS?s Scientific Manuscript database

    To study the cellular mechanisms involved in fiber initiation, three fiberless lines were crossed with wildtype and fuzzless seed cotton and the F1, F2 and BC1 progeny ratios are presently being evaluated. The three fiberless lines included: MD17 (N1N1n2n2), SL1-7-1 (N1N1fl1fl1n3n3) and XZ142w. XZ...

  2. COTS Initiative Panel Discussion

    NASA Image and Video Library

    2013-11-13

    Gwynne Shotwell, President of SpaceX, delivers remarks panel discussion on the Commercial Orbital Transportation Services (COTS) initiative at NASA Headquarters in Washington on Wednesday, November 13, 2013. Through COTS, NASA's partners Space Exploration Technologies Corp. (SpaceX) and Orbital Sciences Corp., developed new U.S. rockets and spacecraft, launched from U.S. soil, capable of transporting cargo to low-Earth orbit and the International Space Station. Photo Credit: (NASA/Jay Westcott)

  3. COTS Initiative Panel Discussion

    NASA Image and Video Library

    2013-11-13

    NASA Administrator Charles Bolden delivers remarks before a panel discussion on the Commercial Orbital Transportation Services (COTS) initiative at NASA Headquarters in Washington on Wednesday, November 13, 2013. Through COTS, NASA's partners Space Exploration Technologies Corp. (SpaceX) and Orbital Sciences Corp., developed new U.S. rockets and spacecraft, launched from U.S. soil, capable of transporting cargo to low-Earth orbit and the International Space Station. Photo Credit: (NASA/Jay Westcott)

  4. COTS Initiative Panel Discussion

    NASA Image and Video Library

    2013-11-13

    Frank Slazer, Vice President of Space Systems, Aerospace Industries Association, delivers remarks panel discussion on the Commercial Orbital Transportation Services (COTS) initiative at NASA Headquarters in Washington on Wednesday, November 13, 2013. Through COTS, NASA's partners Space Exploration Technologies Corp. (SpaceX) and Orbital Sciences Corp., developed new U.S. rockets and spacecraft, launched from U.S. soil, capable of transporting cargo to low-Earth orbit and the International Space Station. Photo Credit: (NASA/Jay Westcott)

  5. Laser Initiated Actuator study

    SciTech Connect

    Watson, B.

    1991-06-27

    The program task was to design and study a laser initiated actuator. The design of the actuator is described, it being comprised of the fiber and body subassemblies. The energy source for all experiments was a Spectra Diode 2200-H2 laser diode. The diode is directly coupled to a 100 micron core, 0.3 numerical aperture fiber optic terminated with an SMA connector. The successful testing results are described and recommendations are made.

  6. COTS Initiative Panel Discussion

    NASA Image and Video Library

    2013-11-13

    Alan Lindenmoyer, Manager of Commercial Crew and Cargo Program at NASA, delivers remarks panel discussion on the Commercial Orbital Transportation Services (COTS) initiative at NASA Headquarters in Washington on Wednesday, November 13, 2013. Through COTS, NASA's partners Space Exploration Technologies Corp. (SpaceX) and Orbital Sciences Corp., developed new U.S. rockets and spacecraft, launched from U.S. soil, capable of transporting cargo to low-Earth orbit and the International Space Station. Photo Credit: (NASA/Jay Westcott)

  7. The space exploration initiative

    NASA Technical Reports Server (NTRS)

    Priest, Pete

    1991-01-01

    A number of view graph charts are presented which outline the presentation. Outlined are reasons for going to Mars, why it is necessary to go to the Moon first, and the presidential decision on the space exploration initiative. Other representative charts are entitled: Lunar transportation system requirement drivers; Mars transportation system requirement drivers; National space policy goals; Exploration hardware needed; Mars mission profile; Science on the Moon and Mars; and Two independent reviews.

  8. Initiation Train Experiments

    NASA Astrophysics Data System (ADS)

    Francois, Elizabeth; Johnson, Carl; Liechty, Gary; Whitley, Von

    2015-06-01

    In an effort to evaluate and qualify a new detonator diagnostic, booster selection and main charge configuration, a variety of small-scale tests have been conducted. This paper will describe the needs, testing approach and model validation. Because of the limited size available some novel approaches were made to understand the observed phenomenon. Function time and time of arrival at various locations in the initiation train are desirable data points. Knowing when each segment initiates the next segment and the time to run up to detonation is critical. Results of our experiments were modeled for timing accuracy, wave shape and pressure. Agreement between the experiments and models will be discussed. The testing that will be discussed is time of arrival wires, PDV, and fiber optic arrays. The time of arrival wire measures the detonator cup breakout time. When correlated to bridge burst, an absolute time is collected. This data point also gives time zero for the booster initiation. Many models actually start at the booster, rather than the detonator, so the inclusion of this data point will improve modeling efforts.

  9. MSI develops refugee initiative.

    PubMed

    1996-01-01

    This brief article highlights the new initiative by Marie Stopes International (MSI), which is part of a Reproductive Health for Refugees Consortium of four organizations formed in 1995. The new initiative will promote awareness about the need for reproductive health among refugees. Over 80% of refugees are women and children who fled a variety of disasters only to be at high risk from sexual violence, sexually transmitted infections, and the effects of unintended and unsafe pregnancies. The consortium members will work to increase donors' understanding of the health conditions of women and to significantly increase donor support for reproductive health initiatives. In addition to the role of advocacy, MSI will be introducing refugee services into its global network of reproductive health services. MSI gained experience in delivering reproductive health services in refugee situations in the former Yugoslavia and among Mozambican refugees in Malawi. MSI is investigating sources of information from several countries about refugees' needs. The consortium is also collecting information on the most effective ways of delivering reproductive health services in refugee situations. The aim is to institutionalize reproductive health services into all humanitarian responses. MSI has developed refugee programs over the past 3 years in the former Yugoslavia, Malawi, Sri Lanka, and Sierra Leone. MSI expects to establish projects in 1996 for refugees in Zaire, Guinea, and Mozambique. The numbers of displaced persons or refugees is continuing to increase worldwide, and there is a continued need to provide for these vulnerable communities.

  10. Initiation of dialysis.

    PubMed

    Hakim, R M; Lazarus, J M

    1995-11-01

    The decision to initiate dialysis in a patient with progressive renal disease often depends on the physician's assessment of the patient's subjective symptoms of uremia. There is an increasing need to identify objective criteria for such a decision. Recent evidence suggests that malnutrition at the initiation of dialysis is a strong predictor of subsequent increased relative risk of death on dialysis. In this context, the role of prescribed protein restriction as well as the influence of the progression of renal disease on spontaneous dietary protein intake is examined. It is proposed that the indices of malnutrition such as progressive weight loss, serum albumin levels below 4.0 g/dL, serum transferrin levels below 200 mg/dL, and spontaneous dietary protein intake (using 24-hr urinary nitrogen measurement) below 0.8 to 0.7 g/kg per day be considered as objective criteria for the initiation of dialysis. Studies that have examined the role of "early" versus "late" dialysis have consistently shown a better outcome in the patients starting dialysis early. Other studies also suggest that early referral to nephrologists results in improved morbidity and mortality as well as hospitalization costs. An adequate vascular access, as well as social and psychological preparation of the patient, is an important early step in the process.

  11. The Cincinnati Payer Initiative.

    PubMed

    Pruett, S H; Werner, T; Hein, J

    1996-01-01

    In 1991, four companies (Procter & Gamble, General Electric, Cincinnati Bell, and Kroger) located in Cincinnati, OH, decided to cooperate in a collaborative partnership with hospitals and a health care data consulting firm to get more information about the health care options available in their community. The Cincinnati Quality Initiative was formed with the goal of stimulating competition around quality and value in the health care market place. The 14 hospitals in the Cincinnati area were invited to participate in a 3-year program of investigation and analyses. The Initiative implemented the investigation in order to gather information that could be used to make health care choices for their employees. Hospitals that performed well over the 3-year period-those that improved over time-would then be selected by the Initiative. However, this selection process did not occur. Nevertheless, the 3-year evaluation proved useful because it generated valuable information about the health care options in Cincinnati and spurred competition among the hospitals. It also led to a dramatic reduction in health care costs for those hospitals that agreed to participate in the investigation.

  12. MicroRNA-320a and microRNA-4496 attenuate Helicobacter pylori cytotoxin-associated gene A (CagA)-induced cancer-initiating potential and chemoresistance by targeting β-catenin and ATP-binding cassette, subfamily G, member 2.

    PubMed

    Kang, Dong Woo; Yang, Eun Sun; Noh, Yu Na; Hwang, Won Chan; Jo, Se-Young; Suh, Young-Ah; Park, Won Sang; Choi, Kang-Yell; Min, Do Sik

    2017-04-01

    Infection with Helicobacter pylori is closely linked to an increased risk of gastric cancer. Although cytotoxin-associated gene A (CagA), a major virulence factor of H. pylori, is known to be a causal factor for gastric carcinogenesis, the molecular link between CagA and gastric cancer-initiating cell (CIC)-like properties remains elusive. Here, we demonstrate that CagA is required for increased expression of β-catenin and its target CIC markers via downregulation of microRNA (miR)-320a and miR-4496. CagA promoted gastric CIC properties and was responsible for chemoresistance. miR-320a and miR-4496 attenuated the in vitro self-renewal and tumour-initiating capacity of CagA-expressing CICs by targeting β-catenin. Moreover, miR-320a and miR-4496 decreased CagA-induced chemoresistance by targeting ATP-binding cassette, subfamily G, member 2 (ABCG2) at the transcriptional and post-transcriptional levels, respectively. Combination therapy with 5-fluorouracil and miR-320a/miR-4496 suppressed gastric tumourigenesis and metastatic potential in an orthotopic mouse model, probably via suppression of CagA-induced CIC properties and chemoresistance. Our results provide novel evidence that CIC properties, chemoresistance and tumourigenesis associated with H. pylori are linked to CagA-induced upregulation of β-catenin and ABCG2. These data provide novel insights into the molecular mechanisms of CagA-induced carcinogenisis and the therapeutic potential of of miR-320a and miR-4496. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  13. Financial planning for major initiatives: a framework for success.

    PubMed

    Harris, John M

    2007-11-01

    A solid framework for assessing a major strategic initiative consists of four broad steps: Initial considerations, including level of analysis required and resources that will be brought to bear. Preliminary financial estimates for board approval to further assess the initiative. Assessment of potential partners' interest in the project. Feasibility analysis for board green light.

  14. Initial blood storage experiment

    NASA Technical Reports Server (NTRS)

    Surgenor, Douglas MACN.

    1988-01-01

    The design of the Initial Blood Storage Experiment (IBSE) was based upon a carefully controlled comparison between identical sets of human blood cell suspensions - red cells, white cell, and platelets - one set of which was transported aboard the Columbia on a 6 day 11 hour mission, and the other held on the ground. Both sets were carried inside stainless steel dewars within specially fabricated flight hardware. Individual bags of cell suspensions were randomly assigned with respect to ground vs orbit status, dewar chamber, and specific location within the dewar. To foster optimal preservation, each cell type was held under specific optimal conditions of pH, ionic strength, solute concentration, gas tension, and temperature. An added variable in this initial experiment was provided by the use of three different polymer/plasticizer formulations for the sealed bags which held the blood cells. At termination of the experiment, aliquots of the suspensions, identified only by code, were distributed to be assayed. Assays were selected to constitute a broad survey of cellular properties and thereby maximize the chances of detection of gravitational effects. A total of 74 different outcome measurements were reported for statistical analysis. When the measurements were completed, the results were entered into the IBSE data base, at which time the data were matched with the original blood bag numbers to determine their status with respect to polymer/plasticizer type, orbit status (orbit or ground), and storage position within the experimental hardware. The data were studied by analysis of variance. Initially, type of bag and orbital status were main factors; later more detailed analyses were made on specific issues such as position in the hardware and specific plastic. If the analysis of variance indicated a statistical significance at the 5 percent level the corresponding p-value was reported.

  15. Through bulkhead initiator studies

    SciTech Connect

    Begeal, D.R.

    1997-03-01

    This report describes recent work done to demonstrate feasibility of a fail-safe Through Bulkhead Initiator with minimum dimensions and suitable for use in cyclical thermal environments. Much of the ground work for a fail-safe TBI was previously done by A.C. Schwartz. This study is an expansion of Schwartz`s work to evaluate devices with bulkheads of 304 stainless steel and Inconel 718; explosive donors of PETN, BNCP, and a 0.005 inch thick steel flying plate donor traveling at 2.6 mm/{micro}s; and explosive acceptors of PETN and BNCP. Bulkhead thickness were evaluated in the range of 0.040 to 0.180 inch. The explosive acceptors initiated a small HMX pellet to drive a 0.005 inch thick steel flying plate, and VISAR histories of the HMX-driven flying plates were the measure of acceptable performance. A companion set of samples used a PMMA acceptor to measure the particle velocities at the bulkhead/PMMA interface with VISAR. These data were used to compute the input pressure to the acceptor explosives in an attempt to measure initiation threshold. Unfortunately, the range of bulkhead thicknesses tested did not give any failures, thus the threshold was not determined. It was found that either explosive or the flying plate would perform as a TBI in the bulkhead thickness range tested. The optimum TBI is about 0.060 inches thick, and steel bulkheads seem to be more structurally sound than those made of Inconel. That is, cross section views of the Inconel bulkheads showed it to be more prone to stress cracking than was the 304 stainless steel. Both PETN and BNCP showed good performance when tested at {minus}65 F following thermal cycling of {minus}65 F to +165 F. Analysis of the TBI function times showed that BNCP acceptor explosives were undergoing the classical deflagration to detonation process. The PETN acceptors were undergoing prompt detonation.

  16. Hanford tanks initiative plan

    SciTech Connect

    McKinney, K.E.

    1997-07-01

    Abstract: The Hanford Tanks Initiative (HTI) is a five-year project resulting from the technical and financial partnership of the U.S. Department of Energy`s Office of Waste Management (EM-30) and Office of Science and Technology Development (EM-50). The HTI project accelerates activities to gain key technical, cost performance, and regulatory information on two high-level waste tanks. The HTI will provide a basis for design and regulatory decisions affecting the remainder of the Tank Waste Remediation System`s tank waste retrieval Program.

  17. Advanced Monitoring systems initiative

    SciTech Connect

    R.J. Venedam; E.O. Hohman; C.F. Lohrstorfer; S.J. Weeks; J.B. Jones; W.J. Haas

    2004-09-30

    The Advanced Monitoring Systems Initiative (AMSI) actively searches for promising technologies and aggressively moves them from the research bench into DOE/NNSA end-user applications. There is a large unfulfilled need for an active element that reaches out to identify and recruit emerging sensor technologies into the test and evaluation function. Sensor research is ubiquitous, with the seeds of many novel concepts originating in the university systems, but at present these novel concepts do not move quickly and efficiently into real test environments. AMSI is a widely recognized, self-sustaining ''business'' accelerating the selection, development, testing, evaluation, and deployment of advanced monitoring systems and components.

  18. UNLV Nuclear Hydrogen Initiative

    SciTech Connect

    Hechanova, Anthony E.; Johnson, Allen; O'Toole, Brendan; Trabia, Mohamed; Peterson, Per

    2012-10-25

    Evaluation of the Crack growth rate (CGR) of Alloy 617 and Alloy 276 under constant K at ambient temperature has been completed. Creep deformation of Alloy 230 at different temperature range and load level has been completed and heat to heat variation has been noticed. Creep deformation study of Alloy 276 has been completed under an applied initial stress level of 10% of yield stress at 950ºC. The grain size evaluation of the tested creep specimens of Alloy 276 has been completed.

  19. Human Research Initiative (HRI)

    NASA Technical Reports Server (NTRS)

    Motil, Brian

    2003-01-01

    A code U initiative starting in the FY04 budget includes specific funding for 'Phase Change' and 'Multiphase Flow Research' on the ISS. NASA GRC developed a concept for two facilities based on funding/schedule constraints: 1) Two Phase Flow Facility (TphiFFy) which assumes integrating into FIR; 2) Contact Line Dynamics Experiment Facility (CLiDE) which assumes integration into MSG. Each facility will accommodate multiple experiments conducted by NRA selected PIs with an overall goal of enabling specific NASA strategic objectives. There may also be a significant ground-based component.

  20. COTS Initiative Panel Discussion

    NASA Image and Video Library

    2013-11-13

    NASA Administrator Charles Bolden, left, presents NASA's Group Achievement Award to (L-R) Frank Culbertson, Executive Vice President and General Manager, Orbital Sciences Advanced Programs Group,at NASA Headquarters in Washington on Thursday, November 13, 2013. Culbertson received the award for outstanding contributions and innovative accomplishments in the completion of the Commercial Orbital Transportation Services (COTS) initiative. Through COTS, NASA's partners Space Exploration Technologies Corp. (SpaceX) and Orbital Sciences Corp., developed new U.S. rockets and spacecraft, launched from U.S. soil, capable of transporting cargo to low-Earth orbit and the International Space Station. Photo Credit: (NASA/Jay Westcott)

  1. COTS Initiative Panel Discussion

    NASA Image and Video Library

    2013-11-13

    NASA Administrator Charles Bolden, left, presents NASA's Group Achievement Award to Gwynne Shotwell, President, SpaceX, at NASA Headquarters in Washington on Thursday, November 13, 2013. Shotwell received the award for outstanding contributions and innovative accomplishments in the completion of the Commercial Orbital Transportation Services (COTS) initiative. Through COTS, NASA's partners Space Exploration Technologies Corp. (SpaceX) and Orbital Sciences Corp., developed new U.S. rockets and spacecraft, launched from U.S. soil, capable of transporting cargo to low-Earth orbit and the International Space Station. Photo Credit: (NASA/Jay Westcott)

  2. Initiation of slug flow

    SciTech Connect

    Hanratty, T.J.; Woods, B.D.

    1995-12-31

    The initiation of slug flow in a horizontal pipe can be predicted either by considering the stability of a slug or by considering the stability of a stratified flow. Measurements of the shedding rate of slugs are used to define necessary conditions for the existence of a slug. Recent results show that slugs develop from an unstable stratified flow through the evolution of small wavelength waves into large wavelength waves that have the possibility of growing to form a slug. The mechanism appears to be quite different for fluids with viscosities close to water than for fluids with large viscosities (20 centipoise).

  3. Feedback stabilization initiative

    SciTech Connect

    1997-06-01

    Much progress has been made in attaining high confinement regimes in magnetic confinement devices. These operating modes tend to be transient, however, due to the onset of MHD instabilities, and their stabilization is critical for improved performance at steady state. This report describes the Feedback Stabilization Initiative (FSI), a broad-based, multi-institutional effort to develop and implement methods for raising the achievable plasma betas through active MHD feedback stabilization. A key element in this proposed effort is the Feedback Stabilization Experiment (FSX), a medium-sized, national facility that would be specifically dedicated to demonstrating beta improvement in reactor relevant plasmas by using a variety of MHD feedback stabilization schemes.

  4. NASA's Climate Data Services Initiative

    NASA Astrophysics Data System (ADS)

    McInerney, M.; Duffy, D.; Schnase, J. L.; Webster, W. P.

    2013-12-01

    Our understanding of the Earth's processes is based on a combination of observational data records and mathematical models. The size of NASA's space-based observational data sets is growing dramatically as new missions come online. However a potentially bigger data challenge is posed by the work of climate scientists, whose models are regularly producing data sets of hundreds of terabytes or more. It is important to understand that the 'Big Data' challenge of climate science cannot be solved with a single technological approach or an ad hoc assemblage of technologies. It will require a multi-faceted, well-integrated suite of capabilities that include cloud computing, large-scale compute-storage systems, high-performance analytics, scalable data management, and advanced deployment mechanisms in addition to the existing, well-established array of mature information technologies. It will also require a coherent organizational effort that is able to focus on the specific and sometimes unique requirements of climate science. Given that it is the knowledge that is gained from data that is of ultimate benefit to society, data publication and data analytics will play a particularly important role. In an effort to accelerate scientific discovery and innovation through broader use of climate data, NASA Goddard Space Flight Center's Office of Computational and Information Sciences and Technology has embarked on a determined effort to build a comprehensive, integrated data publication and analysis capability for climate science. The Climate Data Services (CDS) Initiative integrates people, expertise, and technology into a highly-focused, next-generation, one-stop climate science information service. The CDS Initiative is providing the organizational framework, processes, and protocols needed to deploy existing information technologies quickly using a combination of enterprise-level services and an expanding array of cloud services. Crucial to its effectiveness, the CDS

  5. Precision flyer initiator

    DOEpatents

    Frank, A.M.; Lee, R.S.

    1998-05-26

    A precision flyer initiator forms a substantially spherical detonation wave in a high explosive (HE) pellet. An explosive driver, such as a detonating cord, a wire bridge circuit or a small explosive, is detonated. A flyer material is sandwiched between the explosive driver and an end of a barrel that contains an inner channel. A projectile or ``flyer`` is sheared from the flyer material by the force of the explosive driver and projected through the inner channel. The flyer than strikes the HE pellet, which is supported above a second end of the barrel by a spacer ring. A gap or shock decoupling material delays the shock wave in the barrel from predetonating the HE pellet before the flyer. A spherical detonation wave is formed in the HE pellet. Thus, a shock wave traveling through the barrel fails to reach the HE pellet before the flyer strikes the HE pellet. The precision flyer initiator can be used in mining devices, well-drilling devices and anti-tank devices. 10 figs.

  6. Precision flyer initiator

    DOEpatents

    Frank, Alan M.; Lee, Ronald S.

    1998-01-01

    A precision flyer initiator forms a substantially spherical detonation wave in a high explosive (HE) pellet. An explosive driver, such as a detonating cord, a wire bridge circuit or a small explosive, is detonated. A flyer material is sandwiched between the explosive driver and an end of a barrel that contains an inner channel. A projectile or "flyer" is sheared from the flyer material by the force of the explosive driver and projected through the inner channel. The flyer than strikes the HE pellet, which is supported above a second end of the barrel by a spacer ring. A gap or shock decoupling material delays the shock wave in the barrel from predetonating the HE pellet before the flyer. A spherical detonation wave is formed in the HE pellet. Thus, a shock wave traveling through the barrel fails to reach the HE pellet before the flyer strikes the HE pellet. The precision flyer initiator can be used in mining devices, well-drilling devices and anti-tank devices.

  7. Global cancer research initiative

    PubMed Central

    Love, Richard R

    2010-01-01

    Cancer is an increasing problem for low- and middle-income countries undergoing an epidemiologic transition from dominantly acute communicable disease to more frequent chronic disease with increased public health successes in the former domain. Progress against cancer in high-income countries has been modest and has come at enormous expense. There are several well-conceived global policy and planning initiatives which, with adequate political will, can favorably impact the growing global cancer challenges. Most financial resources for cancer, however, are spent on diagnosis and management of patients with disease in circumstances where specific knowledge about effective approaches is significantly limited, and the majority of interventions, other than surgery, are not cost-effective in resource-limited countries by global standards. In summary, how to intervene effectively on a global scale for the majority of citizens who develop cancer is poorly defined. In contrast to technology-transfer approaches, markedly increased clinical research activities are more likely to benefit cancer sufferers. In these contexts, a global cancer research initiative is proposed, and mechanisms for realizing such an effort are suggested. PMID:21188101

  8. Strategic defense initiative

    SciTech Connect

    Nichols, J.P.

    1985-01-01

    The Engineering Technology Division has a leading role, including that of program management, in a major new programmatic thrust of the Oak Ridge National Laboratory that is in support of the national Strategic Defense Initiative (SDI). It is appropriate for the Laboratory to become significantly involved in the program because several of the most promising SDI technologies are in areas for which ORNL (together with Y-12 and K-25) have strong capabilities and significant resources. The initial ORNL work in support of the SDI program is focused on three technologies in which ORNL has extensive experience and traditionally strong research and development programs: (1) space nuclear power, (2) flywheel energy storage, and (3) neutral particle beams. The space nuclear program will utilize our capabilities in areas such as refractory materials, high-temperature alkali metal systems, shielding, and instrumentation. Space nuclear reactors capable of supplying multimegawatt levels of electrical power on a continuous and long-term basis are envisioned to be required for a variety of SDI surveillance satellites and space-borne weapons platforms. The feasibility of an alkali metal Rankine power conversion cycle, which has promise of providing high power with a very low system mass, is planned for study.

  9. Initiatives for proliferation prevention

    SciTech Connect

    1997-04-01

    Preventing the proliferation of weapons of mass destruction is a central part of US national security policy. A principal instrument of the Department of Energy`s (DOE`s) program for securing weapons of mass destruction technology and expertise and removing incentives for scientists, engineers and technicians in the newly independent states (NIS) of the former Soviet Union to go to rogue countries or assist terrorist groups is the Initiatives for Proliferation Prevention (IPP). IPP was initiated pursuant to the 1994 Foreign Operations Appropriations Act. IPP is a nonproliferation program with a commercialization strategy. IPP seeks to enhance US national security and to achieve nonproliferation objectives by engaging scientists, engineers and technicians from former NIS weapons institutes; redirecting their activities in cooperatively-developed, commercially viable non-weapons related projects. These projects lead to commercial and economic benefits for both the NIS and the US IPP projects are funded in Russian, Ukraine, Kazakhstan and Belarus. This booklet offers an overview of the IPP program as well as a sampling of some of the projects which are currently underway.

  10. Brazilian Nanotechnology Initiative

    NASA Astrophysics Data System (ADS)

    Fazzio, Adalberto

    2015-03-01

    In Brazil there is intense research activity in nanotechnology, most of these developed in universities and research institutes. The Brazilian Nanotechnology Initiative (BNI) aims to integrate government actions to promote the competitiveness of the Brazilian industry. This initiative is founded on support for research and development in the laboratories of the National Laboratories for Nanotechnology (SisNANO), starting from an improvement in infrastructure and opening of laboratories for users of academia and business, promoting interaction and transfer knowledge between academia and business. Country currently has 26 thematic networks of nanotechnology, 16 -Virtual-National Institutes of Technology, seven National- Laboratories and 18 Associate Laboratories, which comprise the SisNANO. Seeking to expand and share governance with other government actors, the Interministries Committee for Nanotechnology was set up, composed of 10 ministries, and has the task of coordinating the entire program of the Federal Government Nanotechnology.Cooperation activities are an important part of BNI. Currently Brazil has cooperation programs with U.S., China, Canada and European Union among others. Recently, Brazil decided to join the European NanoReg program where 60 research groups are joining efforts to provide protocols and standards that can help regulatory agencies and governments.

  11. Ensemble decadal predictions from analysed initial conditions.

    PubMed

    Troccoli, Alberto; Palmer, T N

    2007-08-15

    Sensitivity experiments using a coupled model initialized from analysed atmospheric and oceanic observations are used to investigate the potential for interannual-to-decadal predictability. The potential for extending seasonal predictions to longer time scales is explored using the same coupled model configuration and initialization procedure as used for seasonal prediction. It is found that, despite model drift, climatic signals on interannual-to-decadal time scales appear to be detectable. Two climatic states have been chosen: one starting in 1965, i.e. ahead of a period of global cooling, and the other in 1994, ahead of a period of global warming. The impact of initial conditions and of the different levels of greenhouse gases are isolated in order to gain insights into the source of predictability.

  12. HRD Initiatives Contributing to Women's Career Progress.

    ERIC Educational Resources Information Center

    McDonald, Kimberly S.; Hite, Linda M.

    1999-01-01

    Highlights findings from the literature on management development experiences that influence women's advancement. Discusses results of a study of 27 female managers about their participation in management development. Describes four human resource development (HRD) initiatives with the potential to enhance women's management development: training,…

  13. Small Spacecraft Technology Initiative Education Program

    NASA Technical Reports Server (NTRS)

    1995-01-01

    A NASA engineer with the Commercial Remote Sensing Program (CRSP) at Stennis Space Center works with students from W.P. Daniels High School in New Albany, Miss., through NASA's Small Spacecraft Technology Initiative Program. CRSP is teaching students to use remote sensing to locate a potential site for a water reservoir to offset a predicted water shortage in the community's future.

  14. Small Spacecraft Technology Initiative Education Program

    NASA Technical Reports Server (NTRS)

    1995-01-01

    A NASA engineer with the Commercial Remote Sensing Program (CRSP) at Stennis Space Center works with students from W.P. Daniels High School in New Albany, Miss., through NASA's Small Spacecraft Technology Initiative Program. CRSP is teaching students to use remote sensing to locate a potential site for a water reservoir to offset a predicted water shortage in the community's future.

  15. Spinodal backreaction during inflation and initial conditions

    SciTech Connect

    Richard, Benoit J.; Sandora, McCullen E-mail: sandora@cp3.dias.sdu.dk

    2015-08-01

    We investigate how long wavelength inflationary fluctuations can cause the background field to deviate from classical dynamics. For generic potentials, we show that, in the Hartree approximation, the long wavelength dynamics can be encapsulated by a two-field model operating in an effective potential. The latter is given by a simple Gaussian integral transformation of the original inflationary potential. We use this new expression to study backreaction effects in quadratic, hilltop, flattened, and axion monodromy potentials. We find that the net result of the altered dynamics is to slightly modify the spectral tilt, drastically decrease the tensor-to-scalar ratio, and to effectively smooth over any features of the potential, with the size of these deviations set by the initial value of power in large scale modes and the shape of the potential during the entire evolution.

  16. Advances in Modeling Exploding Bridgewire Initiation

    SciTech Connect

    Hrousis, C A; Christensen, J S

    2010-03-10

    There is great interest in applying magnetohydrodynamic (MHD) simulation techniques to the designs of electrical high explosive (HE) initiators, for the purpose of better understanding a design's sensitivities, optimizing its performance, and/or predicting its useful lifetime. Two MHD-capable LLNL codes, CALE and ALE3D, are being used to simulate the process of ohmic heating, vaporization, and plasma formation in exploding bridgewires (EBW). Initiation of the HE is simulated using Ignition & Growth reactive flow models. 1-D, 2-D and 3-D models have been constructed and studied. The models provide some intuitive explanation of the initiation process and are useful for evaluating the potential impact of identified aging mechanisms (such as the growth of intermetallic compounds or powder sintering). The end product of this work is a simulation capability for evaluating margin in proposed, modified or aged initiation system designs.

  17. Electrogenic Tuning of the Axon Initial Segment

    PubMed Central

    Clark, Brian D.; Goldberg, Ethan M.; Rudy, Bernardo

    2010-01-01

    Action potentials (APs) provide the primary means of rapid information transfer in the nervous system. Where exactly these signals are initiated in neurons has been a basic question in neurobiology and the subject of extensive study. Converging lines of evidence indicate that APs are initiated in a discrete and highly specialized portion of the axon—the axon initial segment (AIS). The authors review key aspects of the organization and function of the AIS and focus on recent work that has provided important insights into its electrical signaling properties. In addition to its main role in AP initiation, the new findings suggest that the AIS is also a site of complex AP modulation by specific types of ion channels localized to this axonal domain. PMID:20007821

  18. A mechanical energy analysis of gait initiation

    NASA Technical Reports Server (NTRS)

    Miller, C. A.; Verstraete, M. C.

    1999-01-01

    The analysis of gait initiation (the transient state between standing and walking) is an important diagnostic tool to study pathologic gait and to evaluate prosthetic devices. While past studies have quantified mechanical energy of the body during steady-state gait, to date no one has computed the mechanical energy of the body during gait initiation. In this study, gait initiation in seven normal male subjects was studied using a mechanical energy analysis to compute total body energy. The data showed three separate states: quiet standing, gait initiation, and steady-state gait. During gait initiation, the trends in the energy data for the individual segments were similar to those seen during steady-state gait (and in Winter DA, Quanbury AO, Reimer GD. Analysis of instantaneous energy of normal gait. J Biochem 1976;9:253-257), but diminished in amplitude. However, these amplitudes increased to those seen in steady-state during the gait initiation event (GIE), with the greatest increase occurring in the second step due to the push-off of the foundation leg. The baseline level of mechanical energy was due to the potential energy of the individual segments, while the cyclic nature of the data was indicative of the kinetic energy of the particular leg in swing phase during that step. The data presented showed differences in energy trends during gait initiation from those of steady state, thereby demonstrating the importance of this event in the study of locomotion.

  19. A mechanical energy analysis of gait initiation

    NASA Technical Reports Server (NTRS)

    Miller, C. A.; Verstraete, M. C.

    1999-01-01

    The analysis of gait initiation (the transient state between standing and walking) is an important diagnostic tool to study pathologic gait and to evaluate prosthetic devices. While past studies have quantified mechanical energy of the body during steady-state gait, to date no one has computed the mechanical energy of the body during gait initiation. In this study, gait initiation in seven normal male subjects was studied using a mechanical energy analysis to compute total body energy. The data showed three separate states: quiet standing, gait initiation, and steady-state gait. During gait initiation, the trends in the energy data for the individual segments were similar to those seen during steady-state gait (and in Winter DA, Quanbury AO, Reimer GD. Analysis of instantaneous energy of normal gait. J Biochem 1976;9:253-257), but diminished in amplitude. However, these amplitudes increased to those seen in steady-state during the gait initiation event (GIE), with the greatest increase occurring in the second step due to the push-off of the foundation leg. The baseline level of mechanical energy was due to the potential energy of the individual segments, while the cyclic nature of the data was indicative of the kinetic energy of the particular leg in swing phase during that step. The data presented showed differences in energy trends during gait initiation from those of steady state, thereby demonstrating the importance of this event in the study of locomotion.

  20. Quality initiative at ESO

    NASA Astrophysics Data System (ADS)

    Rupprecht, Gero; Arsenault, Robin; Hanuschik, Reinhard; Kraus, Maximilian; Sivera, Paola; Tromp, Arnout; Verzichelli, Gianluca

    2016-08-01

    An initiative is under way at ESO Headquarters to optimise operations, in particular in the engineering, technical and associated management areas. A systematic approach to strengthen the operating processes is in preparation, starting with a mapping of the extensive existing process network. Processes identified as sufficiently important and complex to merit an in-depth analysis will be properly specified and their implementation optimised to strike a sensible balance between organisational overhead (documentation) and efficiency. By applying methods and tools tried and tested in industry we expect to achieve a more unified approach to address recurrent tasks. This will enable staff to concentrate more on new challenges and improvement and avoid spending effort on issues already resolved in the past.

  1. Instrumented Pipeline Initiative

    SciTech Connect

    Thomas Piro; Michael Ream

    2010-07-31

    This report summarizes technical progress achieved during the cooperative agreement between Concurrent Technologies Corporation (CTC) and U.S. Department of Energy to address the need for a for low-cost monitoring and inspection sensor system as identified in the Department of Energy (DOE) National Gas Infrastructure Research & Development (R&D) Delivery Reliability Program Roadmap.. The Instrumented Pipeline Initiative (IPI) achieved the objective by researching technologies for the monitoring of pipeline delivery integrity, through a ubiquitous network of sensors and controllers to detect and diagnose incipient defects, leaks, and failures. This report is organized by tasks as detailed in the Statement of Project Objectives (SOPO). The sections all state the objective and approach before detailing results of work.

  2. Materials Genome Initiative

    NASA Technical Reports Server (NTRS)

    Vickers, John

    2015-01-01

    The Materials Genome Initiative (MGI) project element is a cross-Center effort that is focused on the integration of computational tools to simulate manufacturing processes and materials behavior. These computational simulations will be utilized to gain understanding of processes and materials behavior to accelerate process development and certification to more efficiently integrate new materials in existing NASA projects and to lead to the design of new materials for improved performance. This NASA effort looks to collaborate with efforts at other government agencies and universities working under the national MGI. MGI plans to develop integrated computational/experimental/ processing methodologies for accelerating discovery and insertion of materials to satisfy NASA's unique mission demands. The challenges include validated design tools that incorporate materials properties, processes, and design requirements; and materials process control to rapidly mature emerging manufacturing methods and develop certified manufacturing processes

  3. [Advanced Composites Technology Initiatives

    NASA Technical Reports Server (NTRS)

    Julian, Mark R.

    2002-01-01

    This final report closes out the W02 NASA Grant #NCC5-646. The FY02 grant for advanced technology initiatives through the Advanced Composites Technology Institute in Bridgeport, WV, at the Robert C. Byrd Institute (RCBI) Bridgeport Manufacturing Technology Center, is complete; all funding has been expended. RCBI continued to expand access to technology; develop and implement a workforce-training curriculum; improve material development; and provide prototyping and demonstrations of new and advanced composites technologies for West Virginia composites firms. The FY 02 efforts supported workforce development, technical training and the HST development effort of a super-lightweight composite carrier prototype and expanded the existing technical capabilities of the growing aerospace industry across West Virginia to provide additional support for NASA missions. Additionally, the Composites Technology and Training Center was awarded IS0 9001 - 2000 certification and Cleanroom Class 1000 certification during this report period.

  4. Breckinridge Project, initial effort

    SciTech Connect

    None, None

    1982-09-01

    Report III, Volume 1 contains those specifications numbered A through J, as follows: General Specifications (A); Specifications for Pressure Vessels (C); Specifications for Tanks (D); Specifications for Exchangers (E); Specifications for Fired Heaters (F); Specifications for Pumps and Drivers (G); and Specifications for Instrumentation (J). The standard specifications of Bechtel Petroleum Incorporated have been amended as necessary to reflect the specific requirements of the Breckinridge Project, and the more stringent specifications of Ashland Synthetic Fuels, Inc. These standard specifications are available to the Initial Effort (Phase Zero) work performed by all contractors and subcontractors. Report III, Volume 1 also contains the unique specifications prepared for Plants 8, 15, and 27. These specifications will be substantially reviewed during Phase I of the project, and modified as necessary for use during the engineering, procurement, and construction of this project.

  5. Congress initiates science study

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    The U.S. House of Representatives announced in October a year-long study to review the nation's science and technology policy and the government's role in funding scientific research. The Science Policy Study, led by Rep. Vernon Ehlers (R-MI), is the first comprehensive review by Congress since 1985—a time when the Cold War still was being fought and the Internet was largely unknown.At a workshop to discuss the initiative, House Science Committee Chair James Sensenbrenner, Jr., told about 30 scientists and policy experts that the challenge is “to develop a new, sensible, coherent long-range science and technology policy, including a review of our nation's science and math education programs.”

  6. COTS Initiative Panel Discussion

    NASA Image and Video Library

    2013-11-13

    L-R: Alan Lindenmoyer, Manager of Commercial Crew and Cargo Program, NASA; Gwynne Shotwell, President, SpaceX; Frank Culbertson, Executive Vice President and General Manager, Orbital Sciences Advanced Programs Group; Frank Slazer, Vice President of Space Systems, Aerospace Industries Association and Phil McAlister, Director of Commercial Spaceflight Development at NASA, participate in a panel discussion on the Commercial Orbital Transportation Services (COTS) initiative at NASA Headquarters in Washington on Wednesday, November 13, 2013. Through COTS, NASA's partners Space Exploration Technologies Corp. (SpaceX) and Orbital Sciences Corp., developed new U.S. rockets and spacecraft, launched from U.S. soil, capable of transporting cargo to low-Earth orbit and the International Space Station. Photo Credit: (NASA/Jay Westcott)

  7. The Knowledge Stealing Initiative?

    NASA Technical Reports Server (NTRS)

    Goshorn, Larry

    2005-01-01

    I have the honor of being on the Academy of Program and Project Leadership (APPL) Knowledge Sharing Feedback and Assessment Team (FAA), and as such, I am privileged to receive the feedback written by many of you as attendees of the Project Management (PM) Master s Forums. It is the intent of the FAA Team and APPL leadership to use this feedback as a tool for continuous program improvement. As a retired (sort of) PM in the payload contracting industry, I'm a big supporter of NASA s Knowledge Sharing Initiative (KSI), especially the Master's Forums. I really enjoy participating in them. Unfortunately I had to miss the 8th forum in Pasadena this past Spring, but I did get the feedback package for the Assessment Team work. So here I was, reviewing twelve pages of comments, reflections, learning notes and critiques from attendees of the 8th forum.

  8. Green Power Initiative

    SciTech Connect

    Butler, Patrick Barry

    2013-01-28

    National energy policy supports the gathering of more detailed and authoritative data on the introduction of renewable bio-based fuels into new and existing district energy systems via the application of biomass gasification. The University of Iowa developed a biomass-fueled, university-scale steam generation system based on biomass gasification technologies. The system serves as a state-of-the-art research and educational facility in the emerging application of gasification in steam generation. The facility, which includes a smaller down-draft gasifier and a larger multi-stage biomass boiler, was designed to operate primarily on wood-based fuels, but has provisions for testing other biomass fuel sources produced within a 100-mile radius, providing enough flexibility to meet the fluctuating local supply of biomass from industry and Midwest agriculture. The equipment was installed in an existing, staffed facility. The down-draft gasifier unit is operated by College of Engineering staff and students, under the direct technical supervision of qualified Utilities plant staff. The Green Power Initiative also includes a substantial, innovative educational component. In addition to an onsite, graduate-level research program in biomass fuels, the investigators have integrated undergraduate and graduate level teaching – through classroom studies and experiential learning – and applied research into a biomass-based, university-scale, functioning power plant. University of Iowa is unique in that it currently has multiple renewable energy technologies deployed, including significant biomass combustion (oat hulls) at its Main Power Plant and a new reciprocating engine based renewable district energy system. This project complements and supports the national energy policy and State of Iowa initiatives in ethanol and biodiesel. Byproducts of ethanol and biodiesel processes (distiller grains) as well as industry residues (oat hulls, wood chips, construction and demolition

  9. Scientific Component Technology Initiative

    SciTech Connect

    Kohn, S; Bosl, B; Dahlgren, T; Kumfert, G; Smith, S

    2003-02-07

    The laboratory has invested a significant amount of resources towards the development of high-performance scientific simulation software, including numerical libraries, visualization, steering, software frameworks, and physics packages. Unfortunately, because this software was not designed for interoperability and re-use, it is often difficult to share these sophisticated software packages among applications due to differences in implementation language, programming style, or calling interfaces. This LDRD Strategic Initiative investigated and developed software component technology for high-performance parallel scientific computing to address problems of complexity, re-use, and interoperability for laboratory software. Component technology is an extension of scripting and object-oriented software development techniques that specifically focuses on the needs of software interoperability. Component approaches based on CORBA, COM, and Java technologies are widely used in industry; however, they do not support massively parallel applications in science and engineering. Our research focused on the unique requirements of scientific computing on ASCI-class machines, such as fast in-process connections among components, language interoperability for scientific languages, and data distribution support for massively parallel SPMD components.

  10. TFTR initial operations

    SciTech Connect

    Young, K.M.; Bell, M.; Blanchard, W.R.; Bretz, N.; Cecchi, J.; Coonrod, J.; Davis, S.; Dylla, H.F.; Efthimion, P.C.; Fonck, R.

    1983-11-01

    The Tokamak Fusion Test Reactor (TFTR) has operated since December 1982 with ohmically heated plasmas. Routine operation with feedback control of plasma current, position, and density has been obtained for plasmas with I/sub p/ approx. = 800 kA, a = 68 cm, R = 250 cm, and B/sub t/ = 27 kG. A maximum plasma current of 1 MA was achieved with q approx. = 2.5. Energy confinement times of approx. 150 msec were measured for hydrogen and deuterium plasmas with anti n/sub e/ approx. = 2 x 10/sup 13/ cm/sup -3/, T/sub e/ (0) approx. = 1.5 keV, T/sub i/ (0) approx. = 1.5 keV, and Z/sub eff/ approx. = 3. The preliminary results suggest a size-cubed scaling from PLT and are consistent with Alcator C scaling where tau approx. nR/sup 2/a. Initial measurements of plasma disruption characteristics indicate current decay rates of approx. 800 kA in 8 ms which is within the TFTR design requirement of 3 MA in 3 ms.

  11. ALOS-2 initial results

    NASA Astrophysics Data System (ADS)

    Kankaku, Yukihiro; Suzuki, Shinichi; Shimada, Masanobu

    2015-10-01

    The Advanced Land Observing Satellite-2 (ALOS-2) was launched from Tanegashima Space Center by H-IIA rocket successfully on 24th May 2014. ALOS-2 carries the Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2) as the state-of-the-art L-band SAR system which succeeds to PALSAR onboard ALOS. PALSAR-2 uses almost whole bandwidth allocated for L-band active sensor of Earth Exploration Satellites Service specified by the Radio Regulation in order to realize the high resolution observation, and also, it transmits more than 6 kW power for lower Noise Equivalent Sigma Zero using 180 TRMs driven by Gallium Nitride (GaN) amplifier which is the first use in space. Furthermore, because ALOS-2 carries the SAR system only, PALSAR-2 antenna can be mounted under the satellite body. It enables to observe right-/left-looking observation by satellite maneuvering. And the high accuracy orbit control to maintain the satellite within 500 m radius tube against the reference orbit enables high coherence for the InSAR processing. Using these new technologies, ALOS-2 has been operating to fulfill the mission requirements such as disaster monitoring and so on. This document introduces the initial result of ALOS-2 from the first year operation.

  12. Urban Environment Initiative

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Urban Environment Initiative (UEI), has been established as part of a Cooperative Agreement with the National Aeronautics and Space Administration (NASA). The UEI is part of NASA's overall High Performance Computing and Communications (HPCC) and the Information Infrastructure Technology Applications (IITA) programs. The goal of the UEI is to provide public access to Earth Science information and promote its use with a focus on the environment of urban areas. This goal will be accomplished through collaborative efforts of the UEI team with both community-based and local/regional governmental organizations. The UEI team is comprised of four organizations representing private industry, NASA, and universities: Prime Technologies Service Corporation, NASA's Minority University Space Interdisciplinary Network (MU-SPIN) California State University, at Los Angeles, and Central State University (Wilberforce, OH). "Urban Environment" refers to the web of environmental, economic, and social factors that combine to create the urban world in which we live. Examples of these factors are population distribution, neighborhood demographic profiles, economic resources, business activities, location and concentration of environmental hazards and various pollutants, proximity and level of urban services, which form the basis of the urban environment and ultimately affect our lives and experiences. The use of Geographic Information Systems (GIS) and remote sensing allows data to be visualized in the forms of maps and spatial images. The use of these tools allow analysis of information about urban environments. Also included are descriptions of the four query types which will assist in understanding the maps.

  13. Moon-Mars Initiative

    NASA Astrophysics Data System (ADS)

    2005-06-01

    On 27 May, the AGU Council unanimously adopted a position statement on NASA's strategic plan released in February 2005:: "A New Age of Exploration: NASA's Direction for 2005 and Beyond". This strategy incorporates U.S. President Bush's vision for manned space flight to Moon and Mars as described in "A Renewed Spirit of Discovery: The President's Vision for U.S. Space Exploration" announced in January 2004. The statement was drafted by a panel chaired by Eric Barron of Penn State University. AGU calls for the U.S. Administration, Congress, and NASA to continue their commitment to innovative Earth and space science programs. This commitment has placed the U.S. in an international leadership position. It enables environmental stewardship, promotes economic vitality, engages the next generation of scientists and engineers, protects life and property, and fosters exploration. It is, however, threatened by new financial demands placed on NASA by the return to human space flight using the space shuttle, finishing the space station, and launching the Moon-Mars initiative.

  14. Urban Environment Initiative

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The Urban Environment Initiative (UEI), has been established as part of a Cooperative Agreement with the National Aeronautics and Space Administration (NASA). The UEI is part of NASA's overall High Performance Computing and Communications (HPCC) and the Information Infrastructure Technology Applications (IITA) programs. The goal of the UEI is to provide public access to Earth Science information and promote its use with a focus on the environment of urban areas. This goal will be accomplished through collaborative efforts of the UEI team with both community-based and local/regional governmental organizations. The UEI team is comprised of four organizations representing private industry, NASA, and universities: Prime Technologies Service Corporation, NASA's Minority University Space Interdisciplinary Network (MU-SPIN) California State University, at Los Angeles, and Central State University (Wilberforce, OH). "Urban Environment" refers to the web of environmental, economic, and social factors that combine to create the urban world in which we live. Examples of these factors are population distribution, neighborhood demographic profiles, economic resources, business activities, location and concentration of environmental hazards and various pollutants, proximity and level of urban services, which form the basis of the urban environment and ultimately affect our lives and experiences. The use of Geographic Information Systems (GIS) and remote sensing allows data to be visualized in the forms of maps and spatial images. The use of these tools allow analysis of information about urban environments. Also included are descriptions of the four query types which will assist in understanding the maps.

  15. Initiation of preterm labor.

    PubMed

    Pawelec, Małgorzata; Pałczyński, Bogusław; Krzemieniewska, Joanna; Karmowski, Mikołaj; Koryś, Jerzy; Lątkowski, Krzysztof; Karmowski, Andrzej

    2013-01-01

    Preterm births are still a major problem in obstetrics. It is estimated that preterm births occur in about 12% of all pregnancies. Due to advances in medical technology and better care of fetuses and premature babies, the preterm mortality rate has been falling (as recently as 1995 the survival rate in the US for premature infants born at 34 weeks amounted to only a fraction of the corresponding rate for those born after 37 weeks). In the US in 2005, preterm births cost society approximately $26 billion, and medical care for premature babies cost more than $51 billion. Only the richest countries can afford such costly medical care. That is why it is not only the individual aspects but also the social aspects that are important when studying preterm birth mechanisms and ways of preventing them. The existing research indicates that both spontaneous mature birth and preterm birth begin and proceed in a similar manner. This is confirmed by the similar involvement in both processes of corticotropin-releasing hormone, urocortin, extracellular stress protein HSP70 (amniotic fluid heat shock protein), prostaglandins, proinflammatory cytokines or glucocorticosteroids. Apparently, at the beginning of either a preterm birth or a term birth, there is a stimulus that ends the development of the fetus or initiates birth. This stimulus works via feedback through placental hormones and through substances present in the fetal membranes, ultimately leading to functional progesterone withdrawal (FPW), thus leaving the uterus sensitive to contractive factors.

  16. The PBRN Initiative

    PubMed Central

    Curro, F.A.; Vena, D.; Naftolin, F.; Terracio, L.; Thompson, V.P.

    2012-01-01

    The NIDCR-supported Practice-based Research Network initiative presents dentistry with an unprecedented opportunity by providing a pathway for modifying and advancing the profession. It encourages practitioner participation in the transfer of science into practice for the improvement of patient care. PBRNs vary in infrastructure and design, and sustaining themselves in the long term may involve clinical trial validation by regulatory agencies. This paper discusses the PBRN concept in general and uses the New York University College of Dentistry’s Practitioners Engaged in Applied Research and Learning (PEARL) Network as a model to improve patient outcomes. The PEARL Network is structured to ensure generalizability of results, data integrity, and to provide an infrastructure in which scientists can address clinical practitioner research interests. PEARL evaluates new technologies, conducts comparative effectiveness research, participates in multidisciplinary clinical studies, helps evaluate alternative models of healthcare, educates and trains future clinical faculty for academic positions, expands continuing education to include “benchmarking” as a form of continuous feedback to practitioners, adds value to dental schools’ educational programs, and collaborates with the oral health care and pharmaceutical industries and medical PBRNs to advance the dental profession and further the integration of dental research and practice into contemporary healthcare (NCT00867997, NCT01268605). PMID:22699662

  17. A methodology for analyzing precursors to earthquake-initiated and fire-initiated accident sequences

    SciTech Connect

    Budnitz, R.J.; Lambert, H.E.; Apostolakis, G.

    1998-04-01

    This report covers work to develop a methodology for analyzing precursors to both earthquake-initiated and fire-initiated accidents at commercial nuclear power plants. Currently, the U.S. Nuclear Regulatory Commission sponsors a large ongoing project, the Accident Sequence Precursor project, to analyze the safety significance of other types of accident precursors, such as those arising from internally-initiated transients and pipe breaks, but earthquakes and fires are not within the current scope. The results of this project are that: (1) an overall step-by-step methodology has been developed for precursors to both fire-initiated and seismic-initiated potential accidents; (2) some stylized case-study examples are provided to demonstrate how the fully-developed methodology works in practice, and (3) a generic seismic-fragility date base for equipment is provided for use in seismic-precursors analyses. 44 refs., 23 figs., 16 tabs.

  18. Matric potential

    Treesearch

    Melvin T. Tyree

    2003-01-01

    Matric potential, r, is a component of water potential, ?, but has different meanings in plant physiology vs. soil science. A rigorous definition of r requires a reference to principles of thermodynamics (both classical and irreversible thermodynamics). A rigorous treatment is beyond the scope of this brief overview. Readers...

  19. Glennan Microsystems Initiative

    NASA Technical Reports Server (NTRS)

    Brillson, Leonard J.

    2002-01-01

    During the 2001-2002 award period, we performed research on Pt/Ti/bare 6H-SiC and bare 4H-SiC interfaces in order to identify their electronic properties as a function of surface preparation. The overall aim of this work is to optimize the electronic properties of metal contacts to SiC as well as the active SiC material itself as a function of surface preparation and subsequent processing. Initially, this work has involved identifying bare surface, subsurface, and metal induced gap states at the metal-SiC contact and correlating energies and densities of deep levels with Schottky barrier heights. We used low energy electron-excited nanoluminescence (LEEN) spectroscopy, X-ray photoemission spectroscopy (XPS), and Secondary Ion Mass Spectrometry (SIMS) in order to correlate electronic states and energy bands with chemical composition, bonding, and crystal structure. A major development has been the discovery of polytype transformations that occur in 4H-SiC under standard microelectronic process conditions used to fabricate SiC devices. Our results are consistent with the stacking fault generation, defect formation, and consequent degradation of SiC recently reported for state-of-the-art ABB commercial diodes under localized electrical stress. Our results highlight the importance of -optimizing process conditions and material properties - anneal times, temperatures and doping to control such structural changes within epitaxial SiC layers. Thus far, we have established threshold times and temperatures beyond which 4H-SiC exhibits 3C-SiC transformation bands for a subset of dopant concentrations and process conditions. On the basis of this temperature time behavior, we have been able to establish an activation energy of approximately 2.5 eV for polytype transformation and dislocation motion. Work continues to establish the fundamental mechanisms underlying the polytype changes and its dependence on material parameters.

  20. Sustainable Forest Bioenergy Initiative

    SciTech Connect

    Breger, Dwayne; Rizzo, Rob

    2011-09-20

    In the state’s Electricity Restructuring Act of 1998, the Commonwealth of Massachusetts recognized the opportunity and strategic benefits to diversifying its electric generation capacity with renewable energy. Through this legislation, the Commonwealth established one of the nation’s first Renewable Energy Portfolio Standard (RPS) programs, mandating the increasing use of renewable resources in its energy mix. Bioenergy, meeting low emissions and advanced technology standards, was recognized as an eligible renewable energy technology. Stimulated by the state’s RPS program, several project development groups have been looking seriously at building large woody biomass generation units in western Massachusetts to utilize the woody biomass resource. As a direct result of this development, numerous stakeholders have raised concerns and have prompted the state to take a leadership position in pursuing a science based analysis of biomass impacts on forest and carbon emissions, and proceed through a rulemaking process to establish prudent policy to support biomass development which can contribute to the state’s carbon reduction commitments and maintain safeguards for forest sustainability. The Massachusetts Sustainable Forest Bioenergy Initiative (SFBI) was funded by the Department of Energy and started by the Department of Energy Resources before these contentious biomass issues were fully raised in the state, and continued throughout the substantive periods of this policy development. Thereby, while SFBI maintained its focus on the initially proposed Scope of Work, some aspects of this scope were expanded or realigned to meet the needs for groundbreaking research and policy development being advanced by DOER. SFBI provided DOER and the Commonwealth with a foundation of state specific information on biomass technology and the biomass industry and markets, the most comprehensive biomass fuel supply assessment for the region, the economic development impact

  1. Initial Ada components evaluation

    NASA Technical Reports Server (NTRS)

    Moebes, Travis

    1989-01-01

    The SAIC has the responsibility for independent test and validation of the SSE. They have been using a mathematical functions library package implemented in Ada to test the SSE IV and V process. The library package consists of elementary mathematical functions and is both machine and accuracy independent. The SSE Ada components evaluation includes code complexity metrics based on Halstead's software science metrics and McCabe's measure of cyclomatic complexity. Halstead's metrics are based on the number of operators and operands on a logical unit of code and are compiled from the number of distinct operators, distinct operands, and total number of occurrences of operators and operands. These metrics give an indication of the physical size of a program in terms of operators and operands and are used diagnostically to point to potential problems. McCabe's Cyclomatic Complexity Metrics (CCM) are compiled from flow charts transformed to equivalent directed graphs. The CCM is a measure of the total number of linearly independent paths through the code's control structure. These metrics were computed for the Ada mathematical functions library using Software Automated Verification and Validation (SAVVAS), the SSE IV and V tool. A table with selected results was shown, indicating that most of these routines are of good quality. Thresholds for the Halstead measures indicate poor quality if the length metric exceeds 260 or difficulty is greater than 190. The McCabe CCM indicated a high quality of software products.

  2. German innovation initiative for nanotechnology

    NASA Astrophysics Data System (ADS)

    Rieke, Volker; Bachmann, Gerd

    2004-10-01

    In many areas of nanotechnology, Germany can count on a good knowledge basis due to its diverse activities in nanosciences. This knowledge basis, when paired with the production and sales structures needed for implementation and the internationally renowned German talent for system integration, should consequently lead to success in the marketplace. And this is exactly the field of application for the innovation initiative "Nanotechnologie erobert Märkte" (nanotechnology conquers markets) and for the new BMBF strategy in support of nanotechnology. Until now, aspects of nanotechnology have been advanced within the confines of their respective technical subject areas. However, the primary aim of incorporating them into an overall national strategy is to build on Germany's well-developed and internationally competitive research in science and technology to tap the potential of Germany's important industrial sectors for the application of nanotechnology through joint research projects (leading-edge innovations) that strategically target the value-added chain. This development is to be supported by government education policy to remedy a threatening shortage of skilled professionals. To realize that goal, forward-looking political policymaking must become oriented to a uniform concept of innovation, one that takes into consideration all facets of new technological advances that can contribute to a new culture of innovation in Germany. And that includes education and research policy as well as a climate that encourages and supports innovation in science, business and society.

  3. Plasma-cathode-initiated vacuum gap closure

    SciTech Connect

    Sampayan, S.E.; Gurbaxani, S.H. ); Buttram, M.T. )

    1990-09-01

    The properties of vacuum gap closure initiated by a plasma cathode are presented. The plasma cathode consisted of approximately 60 surface flashover sites distributed over a 10-cm{sup 2} area. Vacuum gap dimensions were 1{times}7.5 cm in diameter. Faraday cup measurements indicated an ion density greater than 10{sup 12} cm{sup {minus}3}, which was controllable by the amplitude of the initiating high-voltage pulse. Although the field-free expansion velocity of the plasma was measured to be 7 cm/{mu}s, plasma-cathode-initiated closure of the vacuum gap indicated closure speeds on the order of 0.5 cm/{mu}s. Also, increased injected ion density and increased anode-cathode potential resulted in increased closure velocity.

  4. Cable Diagnostic Focused Initiative

    SciTech Connect

    Hartlein, R.A.; Hampton, R.N.

    2010-12-30

    This report summarizes an extensive effort made to understand how to effectively use the various diagnostic technologies to establish the condition of medium voltage underground cable circuits. These circuits make up an extensive portion of the electric delivery infrastructure in the United States. Much of this infrastructure is old and experiencing unacceptable failure rates. By deploying efficient diagnostic testing programs, electric utilities can replace or repair circuits that are about to fail, providing an optimal approach to improving electric system reliability. This is an intrinsically complex topic. Underground cable systems are not homogeneous. Cable circuits often contain multiple branches with different cable designs and a range of insulation materials. In addition, each insulation material ages differently as a function of time, temperature and operating environment. To complicate matters further, there are a wide variety of diagnostic technologies available for assessing the condition of cable circuits with a diversity of claims about the effectiveness of each approach. As a result, the benefits of deploying cable diagnostic testing programs have been difficult to establish, leading many utilities to avoid the their use altogether. This project was designed to help address these issues. The information provided is the result of a collaborative effort between Georgia Tech NEETRAC staff, Georgia Tech academic faculty, electric utility industry participants, as well as cable system diagnostic testing service providers and test equipment providers. Report topics include: •How cable systems age and fail, •The various technologies available for detecting potential failure sites, •The advantages and disadvantages of different diagnostic technologies, •Different approaches for utilities to employ cable system diagnostics. The primary deliverables of this project are this report, a Cable Diagnostic Handbook (a subset of this report) and an online

  5. Technology transfer from the space exploration initiative

    SciTech Connect

    Buden, D.

    1991-06-14

    Space exploration has demonstrated that it stimulates the national economy by creating new and improved products, increased employment, and provides a stimulus to education. The exploration of the Moon and Mars under the Space Exploration Initiative has the potential of accelerating this stimulates to the economy. It is difficult to identify all of the concrete ways this will be accomplished. However, many areas can be identified. The space exploration building blocks of power, propulsion, spacecraft, robotics, rovers, mining and manufacturing, communications, navigation, habitats, life support and infrastructures are reviewed to identify possible technology areas. For example, better means for working in hazardous areas and handling hazardous waste are potential outcomes of this initiative. Methods to produce higher quality goods and improve America`s competitiveness in manufacturing will undoubtedly evolve from the need to produce products that must last many years in the harsh environments of space and planetary surfaces. Some ideas for technology transfer are covered in this paper.

  6. Technology transfer from the space exploration initiative

    SciTech Connect

    Buden, D.

    1991-06-14

    Space exploration has demonstrated that it stimulates the national economy by creating new and improved products, increased employment, and provides a stimulus to education. The exploration of the Moon and Mars under the Space Exploration Initiative has the potential of accelerating this stimulates to the economy. It is difficult to identify all of the concrete ways this will be accomplished. However, many areas can be identified. The space exploration building blocks of power, propulsion, spacecraft, robotics, rovers, mining and manufacturing, communications, navigation, habitats, life support and infrastructures are reviewed to identify possible technology areas. For example, better means for working in hazardous areas and handling hazardous waste are potential outcomes of this initiative. Methods to produce higher quality goods and improve America's competitiveness in manufacturing will undoubtedly evolve from the need to produce products that must last many years in the harsh environments of space and planetary surfaces. Some ideas for technology transfer are covered in this paper.

  7. Robustness of inflation to inhomogeneous initial conditions

    NASA Astrophysics Data System (ADS)

    Clough, Katy; Lim, Eugene A.; DiNunno, Brandon S.; Fischler, Willy; Flauger, Raphael; Paban, Sonia

    2017-09-01

    We consider the effects of inhomogeneous initial conditions in both the scalar field profile and the extrinsic curvature on different inflationary models. In particular, we compare the robustness of small field inflation to that of large field inflation, using numerical simulations with Einstein gravity in 3+1 dimensions. We find that small field inflation can fail in the presence of subdominant gradient energies, suggesting that it is much less robust to inhomogeneities than large field inflation, which withstands dominant gradient energies. However, we also show that small field inflation can be successful even if some regions of spacetime start out in the region of the potential that does not support inflation. In the large field case, we confirm previous results that inflation is robust if the inflaton occupies the inflationary part of the potential. Furthermore, we show that increasing initial scalar gradients will not form sufficiently massive inflation-ending black holes if the initial hypersurface is approximately flat. Finally, we consider the large field case with a varying extrinsic curvature K, such that some regions are initially collapsing. We find that this may again lead to local black holes, but overall the spacetime remains inflationary if the spacetime is open, which confirms previous theoretical studies.

  8. Quantum harmonic oscillator with superoscillating initial datum

    SciTech Connect

    Buniy, R. V.; Struppa, D. C.; Colombo, F.; Sabadini, I.

    2014-11-15

    In this paper, we study the evolution of superoscillating initial data for the quantum driven harmonic oscillator. Our main result shows that superoscillations are amplified by the harmonic potential and that the analytic solution develops a singularity in finite time. We also show that for a large class of solutions of the Schrödinger equation, superoscillating behavior at any given time implies superoscillating behavior at any other time.

  9. Florida Hydrogen Initiative

    SciTech Connect

    Block, David L

    2013-06-30

    The Florida Hydrogen Initiative (FHI) was a research, development and demonstration hydrogen and fuel cell program. The FHI program objectives were to develop Florida?s hydrogen and fuel cell infrastructure and to assist DOE in its hydrogen and fuel cell activities The FHI program funded 12 RD&D projects as follows: Hydrogen Refueling Infrastructure and Rental Car Strategies -- L. Lines, Rollins College This project analyzes strategies for Florida's early stage adaptation of hydrogen-powered public transportation. In particular, the report investigates urban and statewide network of refueling stations and the feasibility of establishing a hydrogen rental-car fleet based in Orlando. Methanol Fuel Cell Vehicle Charging Station at Florida Atlantic University ? M. Fuchs, EnerFuel, Inc. The project objectives were to design, and demonstrate a 10 kWnet proton exchange membrane fuel cell stationary power plant operating on methanol, to achieve an electrical energy efficiency of 32% and to demonstrate transient response time of less than 3 milliseconds. Assessment of Public Understanding of the Hydrogen Economy Through Science Center Exhibits, J. Newman, Orlando Science Center The project objective was to design and build an interactive Science Center exhibit called: ?H2Now: the Great Hydrogen Xchange?. On-site Reformation of Diesel Fuel for Hydrogen Fueling Station Applications ? A. Raissi, Florida Solar Energy Center This project developed an on-demand forecourt hydrogen production technology by catalytically converting high-sulfur hydrocarbon fuels to an essentially sulfur-free gas. The removal of sulfur from reformate is critical since most catalysts used for the steam reformation have limited sulfur tolerance. Chemochromic Hydrogen Leak Detectors for Safety Monitoring ? N. Mohajeri and N. Muradov, Florida Solar Energy Center This project developed and demonstrated a cost-effective and highly selective chemochromic (visual) hydrogen leak detector for safety monitoring

  10. Interatomic Potential

    SciTech Connect

    Gao, Fei

    2010-01-01

    In spite of greatly increased computer speeds, the application of ab initio methods for an atomistic simulation of materials is still limited to relatively small ensembles of atoms and, in molecular dynamics, relatively short simulation times (~5 ps). In contrast, the use of empirical or semiempirical interatomic potentials makes it possible to simulate much larger systems (~ up to a few million atoms) for much longer times (~100 ns), and thus to tackle such problems as plastic deformation, ion-solid interaction, or atomic diffusion. This chapter reviews various interatomic potentials used in large-scale computer simulations.

  11. Modeling Initiation into Drug Injection among Street Youth

    ERIC Educational Resources Information Center

    Roy, Elise; Godin, Gaston; Boudreau, Jean-Francois; Cote, Philippe-Benoit; Denis, Veronique; Haley, Nancy; Leclerc, Pascale; Boivin, Jean-Francois

    2011-01-01

    This study aimed at examining the predictors of initiation into drug injection among street youth using social cognitive theory framework. A prospective cohort study based on semi-annual interviews was carried out. Psychosocial determinants referred to avoidance of initiation. Other potential predictors were: sociodemographic characteristics,…

  12. Hiring Practices Initiative: Uncovering an Untapped Employment Pool

    ERIC Educational Resources Information Center

    Mulvihill, Patrick; Repetto, Jeanne B.; Andrews, Drew; Gritz, Sheila

    2008-01-01

    Through current hiring practices, many school districts may be missing an untapped pool of potential employees--individuals with disabilities. In this article, the authors describe the Hiring Practice Initiative (HPI) and its implementation in 17 Florida school districts. The Hiring Practice Initiative Project goals are to: (a) increase the…

  13. Modeling Initiation into Drug Injection among Street Youth

    ERIC Educational Resources Information Center

    Roy, Elise; Godin, Gaston; Boudreau, Jean-Francois; Cote, Philippe-Benoit; Denis, Veronique; Haley, Nancy; Leclerc, Pascale; Boivin, Jean-Francois

    2011-01-01

    This study aimed at examining the predictors of initiation into drug injection among street youth using social cognitive theory framework. A prospective cohort study based on semi-annual interviews was carried out. Psychosocial determinants referred to avoidance of initiation. Other potential predictors were: sociodemographic characteristics,…

  14. Shock initiation of porous TATB

    SciTech Connect

    Anderson, A.B.; Ginsberg, M.J.; Seitz, W.L.; Wackerle, J.

    1981-01-01

    The planar shock initiation of 1.8-g/cm/sup 3/ TATB has been studied with embedded-Manganin pressure gauges and with the explosive wedge technique. A Lagrangian analysis and an assumed equation of state were used to determine reaction histories during the initiation process. Correlation of reaction rates to state variables has resulted in a shock-strength modified Arrhenius rate law. Numerical simulations employing the rate law have been performed for a number of initiation experiments on TATB.

  15. Initiation into Adolescent Marijuana Use.

    ERIC Educational Resources Information Center

    Brook, Judith S.; And Others

    1980-01-01

    This longitudinal study examined the relationship of three domains (personality/attitudinal orientations, peer relationships, and family socialization factors) with initiation into adolescent marihuana use. (Author/DB)

  16. Initiation into Adolescent Marijuana Use.

    ERIC Educational Resources Information Center

    Brook, Judith S.; And Others

    1980-01-01

    This longitudinal study examined the relationship of three domains (personality/attitudinal orientations, peer relationships, and family socialization factors) with initiation into adolescent marihuana use. (Author/DB)

  17. Open Geodata Initiative for Romania

    NASA Astrophysics Data System (ADS)

    Craciunescu, Vasile; Iosifescu, Ionut; Ilie, Codrina Maria; Gaitanaru, Dragos; Radu Gogu, Constantin; Hurni, Lorenz

    2013-04-01

    The concept of open data access is a very important topic nowadays. The concept assumes that all data collected or generated by public sector bodies (excepting personal data and data protected under existing privacy protection or accessibility rules) is made publicly accessible in commonly-used, machine-readable formats and can be re-used for any purpose, commercial or non-commercial. Governmental agencies are considered to be the most significant data owners and providers in modern societies. The sheer volume and wealth of this data makes apparent the potential benefits of reusing, combining, and processing governmental data. Even though metadata (information about the data) is sometimes published, administrations typically express reluctance to making their data available, for various reasons, cultural, political, legal, institutional and technical. The governmental spatial information (also called geospatial data, georeferenced data or geodata) producers in Romania are no exception -with the additional situation that even metadata is not usually available. Starting from 2013 a joint program between a Swiss partner (The Swiss Federal Institute of Technology ETH- Zurich - Institute of Cartography and Geoinformation) and a Romanian partner (Technical University of Civil Engineering - UTCB) is developed in order to establish a new approach on the open geodata topic. The main objective of the project GEOIDEA.RO (GEodata Openness Initiative for Development and Economic Advancement in ROmania) is to improve the scientific basis for open geodata model adoption in Romania. Is our believe that publishing government geodata in Romania over the Internet,under an open license and in a reusable format can strengthen citizen engagement and yield new innovative businesses, bringing substantial social and economic gains.

  18. The Aerosol Coarse Mode Initiative

    NASA Astrophysics Data System (ADS)

    Arnott, W. P.; Adhikari, N.; Air, D.; Kassianov, E.; Barnard, J.

    2014-12-01

    Many areas of the world show an aerosol volume distribution with a significant coarse mode and sometimes a dominant coarse mode. The large coarse mode is usually due to dust, but sea salt aerosol can also play an important role. However, in many field campaigns, the coarse mode tends to be ignored, because it is difficult to measure. This lack of measurements leads directly to a concomitant "lack of analysis" of this mode. Because, coarse mode aerosols can have significant effects on radiative forcing, both in the shortwave and longwave spectrum, the coarse mode -- and these forcings -- should be accounted for in atmospheric models. Forcings based only on fine mode aerosols have the potential to be misleading. In this paper we describe examples of large coarse modes that occur in areas of large aerosol loading (Mexico City, Barnard et al., 2010) as well as small loadings (Sacramento, CA; Kassianov et al., 2012; and Reno, NV). We then demonstrate that: (1) the coarse mode can contribute significantly to radiative forcing, relative to the fine mode, and (2) neglecting the coarse mode may result in poor comparisons between measurements and models. Next we describe -- in general terms -- the limitations of instrumentation to measure the coarse mode. Finally, we suggest a new initiative aimed at examining coarse mode aerosol generation mechanisms; transport and deposition; chemical composition; visible and thermal IR refractive indices; morphology; microphysical behavior when deposited on snow and ice; and specific instrumentation needs. Barnard, J. C., J. D. Fast, G. Paredes-Miranda, W. P. Arnott, and A. Laskin, 2010: Technical Note: Evaluation of the WRF-Chem "Aerosol Chemical to Aerosol Optical Properties" Module using data from the MILAGRO campaign, Atmospheric Chemistry and Physics, 10, 7325-7340. Kassianov, E. I., M. S. Pekour, and J. C. Barnard, 2012: Aerosols in Central California: Unexpectedly large contribution of coarse mode to aerosol radiative forcing

  19. The Internet 2 Middleware Initiative.

    ERIC Educational Resources Information Center

    Simco, Greg

    2001-01-01

    Discussion of middleware focuses on the Internet 2 Middleware Initiative. Topics include a description of middleware as a layer of software in a distributed system; middleware characteristics, including transparency, portability, reliability, scalability, and interoperability; and the Internet 2 Middleware Initiative which is focused on research…

  20. Washington State's Student Achievement Initiative

    ERIC Educational Resources Information Center

    Pettitt, Maureen; Prince, David

    2010-01-01

    This article describes Washington State's Student Achievement Initiative, an accountability system implemented in 2005-06 that measures students' gains in college readiness, college credits earned, and degree or certificate completion. The goal of the initiative is to increase educational attainment by focusing on the critical momentum points…

  1. Career Technical Education Pathways Initiative

    ERIC Educational Resources Information Center

    California Community Colleges, Chancellor's Office, 2013

    2013-01-01

    California's education system--the largest in the United States--is an essential resource for ensuring strong economic growth in the state. The Career Technical Education Pathways Initiative (referred to as the Initiative in this report), which became law in 2005, brings together community colleges, K-12 school districts, employers, organized…

  2. Antibiotics trapping transcription initiation intermediates

    PubMed Central

    2011-01-01

    Promoter DNA melting, culminating in the loading of the single-stranded DNA template into the RNA polymerase active site, is a key step in transcription initiation. Recently, the first transcription inhibitors found to block distinct steps of promoter melting were characterized. Here, the impact of these studies is discussed with respect to the current models of transcription initiation. PMID:21468230

  3. Maine: Early Head Start Initiatives

    ERIC Educational Resources Information Center

    Center for Law and Social Policy, Inc. (CLASP), 2012

    2012-01-01

    Maine has two initiatives that build on Early Head Start (EHS). The first initiative, Fund for a Healthy Maine, has since 2001 provided tobacco settlement money to existing Head Start and EHS programs to expand the number of children who receive full-day, full-year services. Local programs have the option of using these funds for EHS, depending on…

  4. Two black hole initial data

    SciTech Connect

    Leski, Szymon

    2005-06-15

    The Misner initial data are a standard example of time-symmetric initial data with two apparent horizons. Compact formulae describing such data are presented in the cases of equal or nonequal masses (i.e. isometric or nonisometric horizons). The interaction energy in the 'Schwarzschild + test-particle' limit of the Misner data is analyzed.

  5. Chronic inhibition of brain glycolysis initiates epileptogenesis.

    PubMed

    Samokhina, Evgeniya; Popova, Irina; Malkov, Anton; Ivanov, Anton I; Papadia, Daniela; Osypov, Alexander; Molchanov, Maxim; Paskevich, Svetlana; Fisahn, André; Zilberter, Misha; Zilberter, Yuri

    2017-11-01

    Metabolic abnormalities found in epileptogenic tissue provide considerable evidence of brain hypometabolism, while major risk factors for acquired epilepsy all share brain hypometabolism as one common outcome, suggesting that a breakdown of brain energy homeostasis may actually precede epileptogenesis. However, a causal link between deficient brain energy metabolism and epilepsy initiation has not been yet established. To address this issue we developed an in vivo model of chronic energy hypometabolism by daily intracerebroventricular (i.c.v.) injection of the nonmetabolizable glucose analog 2-deoxy-D-glucose (2-DG) and also investigated acute effects of 2-DG on the cellular level. In hippocampal slices, acute glycolysis inhibition by 2-DG (by about 35%) led to contrasting effects on the network: a downregulation of excitatory synaptic transmission together with a depolarization of neuronal resting potential and a decreased drive of inhibitory transmission. Therefore, the potential acute effect of 2-DG on network excitability depends on the balance between these opposing pre- and postsynaptic changes. In vivo, we found that chronic 2-DG i.c.v. application (estimated transient inhibition of brain glycolysis under 14%) for a period of 4 weeks induced epileptiform activity in initially healthy male rats. Our results suggest that chronic inhibition of brain energy metabolism, characteristics of the well-established risk factors of acquired epilepsy, and specifically a reduction in glucose utilization (typically observed in epileptic patients) can initiate epileptogenesis. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  6. Initial data for black hole collisions

    NASA Astrophysics Data System (ADS)

    Rauber, J. D.

    A problem of considerable interest in relativistic astrophysics is to determine the gravitational radiation produced by collisions of compact objects, such as black holes. Such collisions may occur, for example, in the nuclei of galaxies. This problem requires that one solve the Einstein equation without limiting approximations, for example, as a Cauchy problem. Therefore, one must first construct the initial data. The extrinsic curvature on an initial spacelike hypersurface of two black holes with asisymmetric parallel spins is derived in terms of an analytic infinite series. Other two body configurations are also considered. The extrinsic curvature is constructed so that the resulting spacetime will have the topology of two Einstein-Rosen bridges; a physical equivalence of the top and bottom sheets of the initial hypersurface is also built in. It is shown that one may a priori specify the spins of the two black holes. The extrinsic curvature, so constructed, is not derivable from a potential. An appropriate numerical problem for the conformal factor is posed and examined in the above configurations. Efforts at using multi-grid differencing schemes for solving the differential equations are discussed. In order to time evolve ablack hole interaction or collision, the extrinsic curvature and conformal factor must be completely specified on an initial slice of spacetime.

  7. Initial Data for Black Hole Collisions

    NASA Astrophysics Data System (ADS)

    Rauber, Joel David

    A problem of considerable interest in relativistic astrophysics is to determine the gravitational radiation produced by collisions of compact objects, such as black holes. Such collisions may occur, for example, in the nuclei of galaxies. This problem requires that one solve the Einstein equation without limiting approximations, for example, as a Cauchy problem. Therefore, one must first construct the initial data. The extrinsic curvature on an initial spacelike hypersurface of two black holes with axisymmetric parallel spins is derived in terms of an analytic infinite series. Other two body configurations are also considered. The extrinsic curvature is constructed so that the resulting spacetime will have the topology of two Einstein-Rosen bridges; a physical equivalence of the top and bottom sheets of the initial hypersurface is also built in. It is shown that one may a priori specify the spins of the two black holes. The extrinsic curvature, so constructed, is not derivable from a potential. An appropriate numerical problem for the conformal factor is posed and examined in the above configurations. Efforts at using multi-grid differencing schemes for solving the differential equations are discussed. In order to time evolve a black hole interaction or collision, the extrinsic curvature and conformal factor must be completely specified on an initial slice of spacetime.

  8. EPA`s clean air power initiative

    SciTech Connect

    Critchfield, L.R.

    1997-12-31

    The Clean Air Power Initiative (CAPI) is a multi-stakeholder project intended to improve air pollution control efforts involving the power generating industry. This paper documents the progress made in the first year of the initiative, which included a number of meetings with interested stakeholders and development and analysis of alternative approaches for more efficient and effective pollution control. The project`s goal is to develop an integrated regulatory strategy or three major pollutants emitted from electric power generators; namely, sulfur dioxide, nitrogen oxides, and, potentially, mercury. Major reductions in these pollutants are expected to be needed to reduce the detrimental health effects of ground-level ozone, fine particles, and hazardous air pollutants and reduce the environmental effects of acidification, eutrophication, ecosystem, crop, and materials damage, and regional haze. The Clean Air Power Initiative has considered, where feasible, new approaches to pollution control that recognize the long-range transport of many air pollutants and the economic benefits of emissions trading. The project was initiated by EPA`s Assistant Administrator for Air and Radiation in 1995. As individual companies develop and implement strategies to participate in more competitive power markets, they could benefit from greater certainty in being able to plan for and reduce costs of future environmental regulations. The EPA is interested in reinventing its regulatory approach to reduce the number, administrative complexity, and cost of its requirements while improving the likelihood of achieving environmental results.

  9. Initiation of parturition in humans.

    PubMed

    Drover, J W; Casper, R F

    1983-02-15

    The mechanism by which parturition is initiated in humans is largely unknown. The placenta and fetal membranes appear to play the major role in the initiation of labour, and the fetus may influence the timing of labour. Clinical observations and experiments with animals have revealed that placental neuropeptides may be able to control steroid metabolism and trigger the onset of labour, while the fetus may be able to interact with such events to initiate parturition at an appropriate time. However, further study is needed to determine the role of placental releasing factors and glycoprotein hormones and their ability to control placental steroid metabolism.

  10. Thin-film optical initiator

    DOEpatents

    Erickson, Kenneth L.

    2001-01-01

    A thin-film optical initiator having an inert, transparent substrate, a reactive thin film, which can be either an explosive or a pyrotechnic, and a reflective thin film. The resultant thin-film optical initiator system also comprises a fiber-optic cable connected to a low-energy laser source, an output charge, and an initiator housing. The reactive thin film, which may contain very thin embedded layers or be a co-deposit of a light-absorbing material such as carbon, absorbs the incident laser light, is volumetrically heated, and explodes against the output charge, imparting about 5 to 20 times more energy than in the incident laser pulse.

  11. Space Radiation Program Element Tissue Sharing Initiative

    NASA Technical Reports Server (NTRS)

    Wu, H.; Huff, J. L.; Simonsen, L. C.

    2014-01-01

    Over the years, a large number of animal experiments have been conducted at the NASA Space Radiation Laboratory and other facilities under the support of the NASA Space Radiation Program Element (SRPE). Studies using rodents and other animal species to address the space radiation risks will remain a significant portion of the research portfolio of the Element. In order to maximize scientific return of the animal studies, SRPE is taking the initiative to promote tissue sharing among the scientists in the space radiation research community. This initiative is enthusiastically supported by the community members as voiced in the responses to a recent survey. For retrospective tissue samples, an online platform will be established for the PIs to post a list of the available samples, and to exchange information with the potential recipients. For future animal experiments, a tissue sharing policy is being developed by SRPE.

  12. Radiation Detection Material Discovery Initiative at PNNL

    NASA Astrophysics Data System (ADS)

    Milbrath, Brian

    2006-05-01

    Today's security threats are being met with 30-year old radiation technology. Discovery of new radiation detection materials is currently a slow and Edisonian process. With heightened concerns over nuclear proliferation, terrorism and unconventional warfare, an alternative strategy for identification and development of potential radiation detection materials must be adopted. Through the Radiation Detection Materials Discovery Initiative, PNNL focuses on the science-based discovery of next generation materials for radiation detection by addressing three ``grand challenges'': fundamental understanding of radiation detection, identification of new materials, and accelerating the discovery process. The new initiative has eight projects addressing these challenges, which will be described, including early work, paths forward and the opportunities for collaboration.

  13. Building and maintaining the axon initial segment

    PubMed Central

    Grubb, Matthew S.; Burrone, Juan

    2011-01-01

    The axon initial segment is a unique neuronal subregion involved in the initiation of action potentials and in the control of axonal identity. Recent work has helped our understanding of how this specialised structure develops, not least in identifying possible mechanisms leading to the localisation of the AIS’s master organiser protein, ankyrin-G. The most exciting current work, however, focuses on later aspects of AIS function and plasticity. Recent studies have shown that the AIS is subdivided into distinct structural and functional domains, have demonstrated how the AIS acts as a cytoplasmic barrier for axonal transport, and have discovered that the AIS can be surprisingly plastic in its responses to alterations in neuronal activity. PMID:20537529

  14. Damage detection in initially nonlinear systems

    SciTech Connect

    Bornn, Luke; Farrar, Charles; Park, Gyuhae

    2009-01-01

    The primary goal of Structural Health Monitoring (SHM) is to detect structural anomalies before they reach a critical level. Because of the potential life-safety and economic benefits, SHM has been widely studied over the past decade. In recent years there has been an effort to provide solid mathematical and physical underpinnings for these methods; however, most focus on systems that behave linearly in their undamaged state - a condition that often does not hold in complex 'real world' systems and systems for which monitoring begins mid-lifecycle. In this work, we highlight the inadequacy of linear-based methodology in handling initially nonlinear systems. We then show how the recently developed autoregressive support vector machine (AR-SVM) approach to time series modeling can be used for detecting damage in a system that exhibits initially nonlinear response. This process is applied to data acquired from a structure with induced nonlinearity tested in a laboratory environment.

  15. Great Lakes Initiative (GLI) Clearinghouse

    EPA Pesticide Factsheets

    The Great Lakes Initiative Toxicity Clearinghouse is a central location for information on criteria, toxicity data, exposure parameters and other supporting documents used in developing water quality standards in the Great Lakes watershed.

  16. Green Power Partnership Program Initiatives

    EPA Pesticide Factsheets

    EPA's Green Power Partnership has a number of initiatives that focus on the collective green power efforts within specific sectors and renewable energy procurement strategies, which provide recognition opportunities for Partners and increase awareness.

  17. Universally conserved translation initiation factors.

    PubMed

    Kyrpides, N C; Woese, C R

    1998-01-06

    The process by which translation is initiated has long been considered similar in Bacteria and Eukarya but accomplished by a different unrelated set of factors in the two cases. This not only implies separate evolutionary histories for the two but also implies that at the universal ancestor stage, a translation initiation mechanism either did not exist or was of a different nature than the extant processes. We demonstrate herein that (i) the "analogous" translation initiation factors IF-1 and eIF-1A are actually related in sequence, (ii) the "eukaryotic" translation factor SUI1 is universal in distribution, and (iii) the eukaryotic/archaeal translation factor eIF-5A is homologous to the bacterial translation factor EF-P. Thus, the rudiments of translation initiation would seem to have been present in the universal ancestor stage. However, significant development and refinement subsequently occurred independently on both the bacterial lineage and on the archaeal/eukaryotic line.

  18. Discovery Performs Terminal Initiation Burn

    NASA Image and Video Library

    The terminal initiation burn, a left Orbital Maneuvering System engine firing that gave Discovery one last big push toward the space station, took place Feb. 26, 2011 at 10:33 a.m. The burn lasted ...

  19. Genomics Nursing Faculty Champion Initiative

    PubMed Central

    Jenkins, Jean; Calzone, Kathleen A.

    2016-01-01

    Nurse faculty are challenged to keep up with the emerging and fast-paced field of genomics and the mandate to prepare the nursing workforce to be able to translate genomic research advances into routine clinical care. Using Faculty Champions and other options, the initiative stimulated curriculum development and promoted genomics curriculum integration. The authors summarize this yearlong initiative for undergraduate and graduate nursing faculty. PMID:24300251

  20. Taiwan - AFOSR Nanoscience Initiative Status

    DTIC Science & Technology

    2005-12-06

    InGaN/GaN Quantum Dots --- Growth, Nano- structure Material Analysis, and Optical Characterization, Chih -Chung Yang, National Taiwan University...Embedded in InGaN Quantum Well Structures, Chih -Chung Yang, National Taiwan University • 034019, Integrated Field Emission Devices Based On Carbon...1 Taiwan – AFOSR Nanoscience Initiative Status Presented at the USAF/ Taiwan Nanoscience Initiative Workshop, Honolulu HI 17 February 2005 Air Force

  1. New initiatives in materials security

    SciTech Connect

    Cynthia, G.; Jones, Ph.D.

    2008-07-01

    NRC Mission: To license and regulate the Nation's civilian use of byproduct, source, and special nuclear materials to ensure adequate protection of public health and safety, promote the common defense and security, and protect the environment. Scope of Responsibility: NRC's regulatory mission covers three main areas: - Reactors: commercial reactors for generating electric power and non-power reactors used for research, testing, and training; - Materials: uses of nuclear materials in medical, industrial, and academic settings and facilities that produce nuclear fuel; - Waste: transportation, storage, and disposal of nuclear materials and waste, and decommissioning of nuclear facilities from service. A Changing Environment: - National security is dominant concern; - Obtain appropriate balance between safety and Security initiatives and Operational activities; - Multiple layers of systems, infrastructures for various licensees. Effective Communication: Not easy; Sound bites galore; Nuclear 'phobia'; Acceptability of risk; Balance of cost and benefits; Responsibility of the regulator, licensees and radiation protection professionals. Prioritized Licensee Groups: - High priority: Panoramic irradiators; manufacturers/distributors; - Medium priority: medical and research facilities, radiography, well-logging, broad-scope licenses, self-shielded irradiators, open-field irradiators, and other licensees; - Low priority: Portable gauges. Increased Security Measures: Security Zone; Control Access; Monitor, Detect, Assess, and Respond; Transportation Security; Additional control to secure portable and mobile devices; Liaison with Local Law Enforcement Agencies; Background Investigations and Fingerprinting; License Verification; Document Retention; Information Protection; Orders/Legally binding requirements to more than 3000 licensees. Orders Issued: Large Panoramic Irradiators Security Measures (60 Orders issued 6/03, Inspections done); Manufacturing and Distribution Licensees

  2. Shock Initiation of Energetic Materials at Different Initial Temperatures

    SciTech Connect

    Urtiew, P A; Tarver, C M

    2005-01-14

    Shock initiation is one of the most important properties of energetic materials, which must transition to detonation exactly as intended when intentionally shocked and not detonate when accidentally shocked. The development of manganin pressure gauges that are placed inside the explosive charge and record the buildup of pressure upon shock impact has greatly increased the knowledge of these reactive flows. This experimental data, together with similar data from electromagnetic particle velocity gauges, has allowed us to formulate the Ignition and Growth model of shock initiation and detonation in hydrodynamic computer codes for predictions of shock initiation scenarios that cannot be tested experimentally. An important problem in shock initiation of solid explosives is the change in sensitivity that occurs upon heating (or cooling). Experimental manganin pressure gauge records and the corresponding Ignition and Growth model calculations are presented for two solid explosives, LX-17 (92.5 % triaminotrinitrobenzene (TATB) with 7.5 % Kel-F binder) and LX-04 (85 % octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazine (HMX) with 15 % Viton binder) at several initial temperatures.

  3. Initial state radiation experiment at MAMI

    SciTech Connect

    Mihovilovič, M.; Merkel, H.; Collaboration: A1-Collaboration

    2013-11-07

    In an attempt to contribute further insight into the discrepancy between the Lamb shift and elastic scattering determinations of the proton charge radius, a new experiment at MAMI is underway, aimed at measuring proton form-factors at very low momentum transfers by using a new technique based on initial state radiation. This paper reports on first findings of the pilot measurement performed in 2010, whose main goal was to check the feasibility of the proposed experiment and to recognize and overcome potential obstacles before running the full experiment in 2013.

  4. Potentiality, irreversibility, and death.

    PubMed

    Lizza, John P

    2005-02-01

    There has been growing concern about whether individuals who satisfy neurological criteria for death or who become non-heart-beating organ donors are really dead. This concern has focused on the issue of the potential for recovery that these individuals may still have and whether their conditions are irreversible. In this article I examine the concepts of potentiality and irreversibility that have been invoked in the discussions of the definition of death and non-heart-beating organ donation. I initially focus on the recent challenge by D. Alan Shewmon to accepting any neurological criterion of death. I argue that Shewmon relies on a problematic and unrealistic concept of potentiality, and that a better, more realistic concept of potentiality is consistent with accepting a neurological criterion for death. I then turn to an analysis of how the concept of irreversibility has been used in discussion of non-heart-beating organ donation. Similarly, I argue that some participants in this discussion have invoked a problematic and unrealistic concept of irreversibility. I then propose an alternative, more realistic account of irreversibility that explains how "irreversibility" should be understood in the definition and criteria of death.

  5. Revised CTUIR Renewable Energy Feasibility Study Final Report

    SciTech Connect

    John Cox; Thomas Bailor; Theodore Repasky; Lisa Breckenridge

    2005-10-31

    This preliminary assessment of renewable energy resources on the Umatilla Indian Reservation (UIR) has been performed by CTUIR Department of Science and Engineering (DOSE). This analysis focused primarily identifying renewable resources that may be applied on or near the Umatilla Indian Reservation. In addition preliminary technical and economic feasibility of developing renewable energy resources have been prepared and initial land use planning issues identified. Renewable energies examined in the course of the investigation included solar thermal, solar photovoltaic, wind, bioethanol, bio-diesel and bio-pellet fuel. All renewable energy options studied were found to have some potential for the CTUIR. These renewable energy options are environmentally friendly, sustainable, and compliment many of the policy goals of the CTUIR. This report seeks to provide an overall review of renewable energy technologies and applications. It tries to identify existing projects near to the CTUIR and the efforts of the federal government, state government and the private sector in the renewable energy arena. It seeks to provide an understanding of the CTUIR as an energy entity. This report intends to provide general information to assist tribal leadership in making decisions related to energy, specifically renewable energy deve lopment.

  6. Laser initiation of secondary explosives

    NASA Astrophysics Data System (ADS)

    Renlund, Anita M.; Stanton, Philip L.; Trott, Wayne M.

    Several experiments were performed to investigate the effects of explosive material parameters on energy thresholds for direct laser initiation of secondary explosives. Laser energy requirements for initiation of pentaerythritol tetranitrate (PETN) were decreased for small particle size powder and low density pressings. Promptness of detonation, however, was aided by higher densities. Initiation of PETN was achieved at energies at or below 10 mJ (power densities approximately 0.2 GW sq cm) at laser wavelengths of 1.06 micrometers, 532 nm and 355 nm and strong confinement of the explosive sample assisted build-up to detonation. At 355 and 308 nm PETN could be initiated by irradiation on the bare explosive surface. Hexahydro 1,3,5-trinitro-s-triazine (RDX) was initiated at 308 nm but not at 1.06 micrometers. Hexanitrostibene (HNS) by direct irradiation at any of these wavelengths was successful. The results suggest that if sufficient energy is deposited, a fast deflagration or convective burn is achieved and that this grows to detonation via a conventional deflagration-to-detonation transition.

  7. Pulsed COIL initiated by discharge

    NASA Astrophysics Data System (ADS)

    Yuryshev, Nikolai N.

    2004-06-01

    Pulsed mode makes COIL possible to produce pulses which power can significantly exceed that of CW COIL mode at the same flowrate of chemicals. Such a mode can find application in material treatment, in drilling for oil wells, as an optical locator, in laser frequency conversion via non-linear processes, in laser propulsion, etc. The method of volume generation of iodine atoms was shown to be the most effective one in generation of high power pulses. The base of method is substitution of molecular iodine in operation mixture for iodide which is stable in the mixture with singlet oxygen, and subsequent forced dissociation of iodide. In this approach the advantage of direct I-atom injection in laser active medium is demonstrated. The comparison of experimental results obtained with different sources used for iodide dissociation shows the electric discharge provides significantly higher electrical laser efficiency in comparison with photolysis initiation. At the same time, the specific energy of the electric discharge initiated COIL is at disadvantage in relation with that obtained with photolysis initiation. This fact is a result of active medium temperature increase due to insufficient initiation selectivity of electric discharge. Both longitudinal and transverse electric discharges were investigated as possible sources for laser initiation. The transverse discharge is more promising for increased operation pressure of active medium. The operation pressure is limited by dark reaction of iodide with singlet delta oxygen. The repetitively pulsed operation with repetition rate of up to 75 Hz of pulsed COIL is demonstrated.

  8. Resistances et initiatives a Madagascar (Resistance and Initiatives in Madagascar).

    ERIC Educational Resources Information Center

    Georges, Claude

    1993-01-01

    Discusses the cultural, political, and institutional barriers to population education in Madagascar and the strategies and initiatives that have been adopted to overcome them, including emphasizing the national character of a project, accommodating the values and ideals of the people involved, and assuring teachers of their classroom autonomy.…

  9. Quantum Measurement and Initial Conditions

    NASA Astrophysics Data System (ADS)

    Stoica, Ovidiu Cristinel

    2016-03-01

    Quantum measurement finds the observed system in a collapsed state, rather than in the state predicted by the Schrödinger equation. Yet there is a relatively spread opinion that the wavefunction collapse can be explained by unitary evolution (for instance in the decoherence approach, if we take into account the environment). In this article it is proven a mathematical result which severely restricts the initial conditions for which measurements have definite outcomes, if pure unitary evolution is assumed. This no-go theorem remains true even if we take the environment into account. The result does not forbid a unitary description of the measurement process, it only shows that such a description is possible only for very restricted initial conditions. The existence of such restrictions of the initial conditions can be understood in the four-dimensional block universe perspective, as a requirement of global self-consistency of the solutions of the Schrödinger equation.

  10. Fighting 'personhood' initiatives in the United States.

    PubMed

    Collins, Lee Rubin; Crockin, Susan L

    2012-06-01

    'Personhood' initiatives filed in many states within the United States threaten to impose potentially significant restrictions on infertility treatment, embryo disposition, pre-natal care, abortion, contraception, and stem-cell research, all through attempts to redefine a 'person' or 'human being' as existing from the moment of fertilization or conception, and endowed with the full legal and Constitutional rights of personhood. Virginia's recent, unsuccessful attempt to pass such legislation provides both a dramatic example of these efforts and valuable lessons in the fight against them by infertility advocates and others. Arguments over loss of infertility treatment seemed more persuasive to legislatures than did restrictions on abortion or stem cell research. Indeed, persuading legislators or voters that they could be 'pro-life' and still anti-personhood initiatives was a key strategy, and consumer efforts and media attention were instrumental. The most central lessons, however, may be the degree of intensity and coordinated strategy to shift public perception that lie behind these numerous state efforts, regardless of whether the actual initiatives are won or lost.

  11. Rhinoplasty: initial consultation and examination.

    PubMed

    Khan, Husain Ali

    2012-02-01

    Many cosmetic surgeons consider rhinoplasty to be the most complex surgical and artistically challenging of all aesthetic surgery today. It is the most common facial procedure performed for women and the second most common for men. The art and science of cosmetic rhinoplasty begins with the initial examination. The surgeon must visualize and predict like Leonardo Da Vinci, be a sculptor like Michelangelo, and be an analyzer like Einstein. This article describes the components and complexities of the initial examination in cosmetic rhinoplasty. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Initial conditions and quantum cosmology

    NASA Technical Reports Server (NTRS)

    Hartle, James B.

    1987-01-01

    A theory of initial conditions is necessary for a complete explanation of the presently observed large scale structural features of the universe, and a quantum theory of cosmology is probably needed for its formulation. The kinematics of quantum cosmology are reviewed, and some candidates for a law of initial conditions are discussed. The proposal that the quantum state of a closed universe is the natural analog of the ground state for closed cosmologies and is specified by a Euclidean sum over histories is sketched. When implemented in simple models, this proposal is consistent with the most important large-scale observations.

  13. Initial conditions and quantum cosmology

    NASA Technical Reports Server (NTRS)

    Hartle, James B.

    1987-01-01

    A theory of initial conditions is necessary for a complete explanation of the presently observed large scale structural features of the universe, and a quantum theory of cosmology is probably needed for its formulation. The kinematics of quantum cosmology are reviewed, and some candidates for a law of initial conditions are discussed. The proposal that the quantum state of a closed universe is the natural analog of the ground state for closed cosmologies and is specified by a Euclidean sum over histories is sketched. When implemented in simple models, this proposal is consistent with the most important large-scale observations.

  14. Astronomical Site Testing Initiatives in Africa

    NASA Astrophysics Data System (ADS)

    Buckley, David A. H.; Graham, Edward; Vaughan, Richard; Belay, Solomon; Biressa, Tolu

    2015-08-01

    Two astronomical site testing initiatives are beginning in both Kenya and Ethiopia, with the aim of selecting suitable locations in those countries for modest sized (1-2m) optical telescopes.The first project, in Kenya, has initially involved a desk-top study of ~30 years of low resolution (~80 km) meteorological satellite data from the European Centre for Medium Range Weather Forecasting (so called “ERA-reanalysis” data). This was later supplemented by ~2 years of higher resolution (~12 km) United Kingdom Met Office Limited Area Model for Africa (“Africa-LAM”) data, kindly made available by the British Atmospheric Data Centre (BADC).The analysis looked at cloud cover, aerosol distribution, integrated water vapour and wind conditions, On the basis of this study, we determined a number of regions in the north of Kenya, east of the Rift Valley, which show promise as potential observatory sites. We are now in the process of installing Automatic Weather Stations (AWS) at 3 selected sites (~2000-2700 m altitude) to begin monitoring meteorological conditions over the next few years. It is eventually hoped to supplement this study with instrumentation to allow the measurement of sky brightness, local cloud cover and seeing (e.g. with a DIMM system).A similar program of astronomical site testing is due to start in 2015 in the Lalibela region of northern Ethiopia, at three potential dark sky sites with expected relatively low cloud cover, ranging in altitude from ~3600 to 4100 m.

  15. Cost estimate of initial SSC experimental equipment

    SciTech Connect

    1986-06-01

    The cost of the initial detector complement at recently constructed colliding beam facilities (or at those under construction) has been a significant fraction of the cost of the accelerator complex. Because of the complexity of large modern-day detectors, the time-scale for their design and construction is comparable to the time-scale needed for accelerator design and construction. For these reasons it is appropriate to estimate the cost of the anticipated detector complement in parallel with the cost estimates of the collider itself. The fundamental difficulty with this procedure is that, whereas a firm conceptual design of the collider does exist, comparable information is unavailable for the detectors. Traditionally, these have been built by the high energy physics user community according to their perception of the key scientific problems that need to be addressed. The role of the accelerator laboratory in that process has involved technical and managerial coordination and the allocation of running time and local facilities among the proposed experiments. It seems proper that the basic spirit of experimentation reflecting the scientific judgment of the community should be preserved at the SSC. Furthermore, the formal process of initiation of detector proposals can only start once the SSC has been approved as a construction project and a formal laboratory administration put in place. Thus an ad hoc mechanism had to be created to estimate the range of potential detector needs, potential detector costs, and associated computing equipment.

  16. Enhancing and initiating phage-based therapies

    PubMed Central

    Serwer, Philip; Wright, Elena T; Chang, Juan T; Liu, Xiangan

    2014-01-01

    Drug development has typically been a primary foundation of strategy for systematic, long-range management of pathogenic cells. However, drug development is limited in speed and flexibility when response is needed to changes in pathogenic cells, especially changes that produce drug-resistance. The high replication speed and high diversity of phages are potentially useful for increasing both response speed and response flexibility when changes occur in either drug resistance or other aspects of pathogenic cells. We present strategy, with some empirical details, for (1) using modern molecular biology and biophysics to access these advantages during the phage therapy of bacterial infections, and (2) initiating use of phage capsid-based drug delivery vehicles (DDVs) with procedures that potentially overcome both drug resistance and other present limitations in the use of DDVs for the therapy of neoplasms. The discussion of phage therapy includes (a) historical considerations, (b) changes that appear to be needed in clinical tests if use of phage therapy is to be expanded, (c) recent work on novel phages and its potential use for expanding the capabilities of phage therapy and (d) an outline for a strategy that encompasses both theory and practice for expanding the applications of phage therapy. The discussion of DDVs starts by reviewing current work on DDVs, including work on both liposomal and viral DDVs. The discussion concludes with some details of the potential use of permeability constrained phage capsids as DDVs. PMID:26713220

  17. Driftless Area Initiative Biomass Energy Project

    SciTech Connect

    Wright, Angie; Bertjens, Steve; Lieurance, Mike; Berguson, Bill; Buchman, Dan

    2012-12-31

    The Driftless Area Initiative Biomass Energy Project evaluated the potential for biomass energy production and utilization throughout the Driftless Region of Illinois, Iowa, Minnesota and Wisconsin. The research and demonstration aspect of the project specifically focused on biomass energy feedstock availability and production potential in the region, as well as utilization potential of biomass feedstocks for heat, electrical energy production, or combined heat and power operations. The Driftless Region was evaluated because the topography of the area offers more acres of marginal soils on steep slopes, wooded areas, and riparian corridors than the surrounding “Corn Belt”. These regional land characteristics were identified as potentially providing opportunity for biomass feedstock production that could compete with traditional agriculture commodity crops economically. The project researched establishment methods and costs for growing switchgrass on marginal agricultural lands to determine the economic and quantitative feasibility of switchgrass production for biomass energy purposes. The project was successful in identifying the best management and establishment practices for switchgrass in the Driftless Area, but also demonstrated that simple economic payback versus commodity crops could not be achieved at the time of the research. The project also analyzed the availability of woody biomass and production potential for growing woody biomass for large scale biomass energy production in the Driftless Area. Analysis determined that significant resources exist, but costs to harvest and deliver to the site were roughly 60% greater than that of natural gas at the time of the study. The project contributed significantly to identifying both production potential of biomass energy crops and existing feedstock availability in the Driftless Area. The project also analyzed the economic feasibility of dedicated energy crops in the Driftless Area. High commodity crop prices

  18. Internet 2 Health Sciences Initiative.

    ERIC Educational Resources Information Center

    Simco, Greg

    2003-01-01

    The Internet 2 (I2) health sciences initiative (I2HSI) involves the formulation of applications and supporting technologies, and guidelines for their use in the health sciences. Key elements of I2HSI include use of visualization, collaboration, medical informatics, telemedicine, and educational tools that support the health sciences. Specific…

  19. Synaptic Plasticity and Translation Initiation

    ERIC Educational Resources Information Center

    Klann, Eric; Antion, Marcia D.; Banko, Jessica L.; Hou, Lingfei

    2004-01-01

    It is widely accepted that protein synthesis, including local protein synthesis at synapses, is required for several forms of synaptic plasticity. Local protein synthesis enables synapses to control synaptic strength independent of the cell body via rapid protein production from pre-existing mRNA. Therefore, regulation of translation initiation is…

  20. Initiative Overview & Summary of Research

    ERIC Educational Resources Information Center

    Education Funders Research Initiative, 2013

    2013-01-01

    Education Funders Research Initiative (EdFunders), a project of Philanthropy New York, is supported by a group of diverse funding organizations that have pursued an array of education reform strategies. EdFunders have come together to engage New Yorkers and focus leaders on new research into how to best prepare students for college and…