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1

Phylogeny can be used to make useful predictions of soil-to-plant transfer factors for radionuclides.  

PubMed

Soil-to-plant transfer of radionuclides can be related to plant evolutionary history (phylogeny). For some species and radionuclides the effect is significant enough to be useful in predicting Transfer Factors (TFs). Here a Residual Maximum Likelihood (REML)-based mixed model and a recent plant phylogeny are used to compile data on soil-to-plant transfer of radionuclides and to show how the phylogeny can be used to fill gaps in TFs. Using published data, generic means for TFs are used to anchor the data from REML modelling and hence predict TFs for important groups of plants. Radionuclides of Cs are used as an example. With a generic soil-to-plant TF of 0.07, TFs of 0.035 and 0.085 are predicted for monocot and eudicot gaps, respectively. Also demonstrated is how the known effects of soil conditions can be predicted across plant groups-predicted Cs TFs for gap-filling across all flowering plants are calculated for sandy loams with and without waterlogging. Predictions of TFs for Sr, Co, Cl and Ru are also given. Overall, the results show that general predictions of TFs based on phylogeny are possible-a significant contribution to gap filling for TFs. PMID:20809227

Willey, Neil J

2010-11-01

2

Bioavailability and soil-to-plant transfer factors as indicators of potentially toxic element contamination in agricultural soils.  

PubMed

Soil pollution in agricultural lands poses a serious threat to food safety, and suggests the need for consolidated methods providing advisory indications for soil management and crop production. In this work, the three-step extraction procedure developed by the EU Measurement and Testing Programme and two soil-to-plant transfer factors (relative to total and bioavailable concentration of elements in soil) were applied on polluted agricultural soils from southern Italy to obtain information on the retention mechanisms of metals in soils and on their level of translocation to edible vegetables. The study was carried out in the Sarno river plain of Campania, an area affected by severe environmental degradation potentially impacting the health of those consuming locally produced vegetables. Soil samples were collected in 36 locations along the two main rivers flowing into the plain. In 11 sites, lettuce plants were collected at the normal stage of consumption. According to Italian environmental law governing residential soils, and on the basis of soil background reference values for the study area, we found diffuse pollution by Be, Sn and Tl, of geogenic origin, Cr and Cu from anthropogenic sources such as tanneries and intensive agriculture, and more limited pollution by Pb, Zn and V. It was found that metals polluting soils as a result of human activities were mainly associated to residual, oxidizable and reducible phases, relatively immobile and only potentially bioavailable to plants. By contrast, the essential elements Zn and Cu showed a tendency to become more readily mobile and bioavailable as their total content in soil increased and were more easily transported to the edible parts of lettuce than other pollutants. According to our results, current soil pollution in the studied area does not affect the proportion of metals taken up by lettuce plants and there is a limited health risk incurred. PMID:25217740

Adamo, Paola; Iavazzo, Pietro; Albanese, Stefano; Agrelli, Diana; De Vivo, Benedetto; Lima, Annamaria

2014-12-01

3

Soil to plant transfer of 238 Th on a uranium  

E-print Network

Soil to plant transfer of 238 U, 226 Ra and 232 Th on a uranium mining-impacted soil from species grown in soils from southeastern China contaminated with uranium mine tailings were analyzed. Keywords: Uranium; Thorium; Radium; Tailings-contaminated soil; Soileplant transfer 1. Introduction

Hu, Qinhong "Max"

4

Multivariate soft-modeling to predict radiocesium soil-to-plant transfer.  

PubMed

A multivariate soft-modeling approach based on an exploratory principal component analysis (PCA) followed by a partial least squares regression (PLS) was developed, tested, and validated to estimate radiocesium transfer to grass from readily measurable soil characteristics. A data set with 145 soil samples and 21 soil and plant parameters was used. Samples were soils from various field plots contaminated by the Chernobyl accident (soddy-podzolic and peaty soils), submitted to several agricultural treatments (disking, ploughing, fertilization, and liming). Parameters included soil characteristics and the corresponding radiocesium soil-to-plant transfer factors. PCA of data showed that soil samples were grouped according to the field plots and that they covered a wide range of possible soil-to-plant transfer scenarios. PLS was used to design and build the multivariate prediction model. The soil database was split in two parts: (i) a representative calibration set for training purposes and model building and (ii) a prediction set for external validation and model testing. The regression coefficients of the model confirmed the relevant parametersto describe radiocesium soil-to-plant transfer variation (e.g., phyllosilicate content and NH4+ status), which agreed with previous knowledge on the interaction mechanisms of this radionuclide in soils. The prediction of soil-to-plant transfer was satisfactory with an error of the same order of magnitude as the variability of field replicates. PMID:18589962

Rigol, Anna; Camps, Marta; De Juan, Anna; Rauret, Gemma; Vidal, Miquel

2008-06-01

5

Soil-to-plant transfer factors of radioactive Ca, Sm and Pd isotopes: critical assessment of the use of analogies to derive best-estimates from existing non-specific data.  

PubMed

(45)Ca, (151)Sm and (107)Pd are three radionuclides present in low to intermediate in activity radioactive wastes for which no soil-to-plant Transfer Factors (TF) values are available to be used in biosphere models for Ecological Risk Assessment. In the absence of specific radioecological studies, this work reviews and analyzes the existing literature for stable isotopes of Pd, Sm and Ca in order to derive best estimates for TF values that could be used as Transfer Factors. Alternative methods of extrapolation are also critically assessed. The values have been classified according to climatic zone, plant class and soil type for each element. The overall geometric mean TF values (for all plants and conditions) was calculated as 8.4E-02 for Pd, for which the value of radioRu in TRS-472 is also available. The mean TF for Sm was 4.2E-04. This value was lower than the TF values for radioactive Ce that are proposed as alternative values for Sm in TRS-472. The former may be relevant for long term assessments and the latter could possibly used to describe the short term (151)Sm post-release behaviour. The mean value for Ca is 2.3E-01 but varies considerably among plants of a given class due to the variety of plant Ca uptake behaviors. Alternatively, to limit this variability, Ca data content for dry plant matter, as analyzed using the phylogenetic method, could be used to derive TF values if the conservation of isotopic ratio of (45)Ca to stable Ca in soils and in plants hypothesis is taken into account. The TF for Ca in sub-tropical zones is 10-fold lower than in temperate zones. There is a lot of data available about exchangeable Ca in soil, which mean that we could calculate an available TF. The analysis shows that Ca bioavailability is also a key factor within transfer. PMID:24956582

Henner, Pascale; Hurtevent, Pierre; Thiry, Yves

2014-10-01

6

Estimation of soil-to-plant transfer factors of radiocesium in 99 wild plant species grown in arable lands 1 year after the Fukushima 1 Nuclear Power Plant accident.  

PubMed

One year after the deposition of radionuclides from the Fukushima 1 Nuclear Power Plant (A formal name is Fukushima Daiichi Nuclear Power Station) in March 2011, radiocesium (¹³?Cs, ¹³?Cs) concentrations ([Cs]) were comprehensively investigated in the wild plants of 99 species most of which were annual or summer green perennial herbs and started to grow from April 2012 at the heavily contaminated fields of paddy (three study sites) and upland (one study site) in Fukushima Prefecture. The survey was conducted three times (April, July and October) in the year. In each site, soils (soil cores of 5-cm depth) and plants (aerial shoots) were collected for determination of [Cs] on a dry weight basis, and then the transfer factor (TF) of radiocesium from soil to plant ([Cs]plant/[Cs]soil) was estimated in each species. The [Cs] values of both soils and plants largely varied. However, some species exhibited relatively high TF values (more than 0.4) (e.g., Athyrium yokoscense, Dryopteris tokyoensis, and Cyperus brevifolius), while others exhibited almost negligible values (less than 0.01) (e.g., Salix miyabeana, Humulus scandens, and Elymus tsukushiensis). In addition, judging from the 11 species grown in both paddy and upland fields, TF values were generally higher in the paddy fields. The estimation of phytoextraction efficiency of soil radiocesium by weed communities in the paddy fields suggests that the weed community is not a practical candidate for phytoremediation technique. PMID:24346655

Yamashita, Jun; Enomoto, Takashi; Yamada, Masao; Ono, Toshiro; Hanafusa, Tadashi; Nagamatsu, Tomohiro; Sonoda, Shoji; Yamamoto, Yoko

2014-01-01

7

Will global warming affect soil-to-plant transfer of radionuclides?  

PubMed

Recent assessments of global climate/environmental change are reaching a consensus that global climate change is occurring but there is significant uncertainty over the likely magnitude of this change and its impacts. There is little doubt that all aspects of the natural environment will be impacted to some degree. Soil-to-plant transfer of radionuclides has long been a significant topic in radioecology, both for the protection of humans and the environment from the effects of ionising radiation. Even after five decades of research considerable uncertainty exists as to the interplay of key environmental processes in controlling soil-plant transfer. As many of these processes are, to a lesser or greater extent, climate-dependent, it can be argued that climate/environmental change will impact soil-to-plant transfer of radionuclides and subsequent transfers in specific environments. This discussion attempts to highlight the possible role of climatic and climate-dependent variables in soil-to-plant transfer processes within the overall predictions of climate/environmental change. The work is speculative, and intended to stimulate debate on a theme that radioecology has either ignored or avoided in recent years. PMID:18676067

Dowdall, M; Standring, W; Shaw, G; Strand, P

2008-11-01

8

Accumulation and soil-to-plant transfer of radionuclides in the Nile Delta coastal black sand habitats.  

PubMed

The radionuclide content was estimated in the soil of three black sand habitats in the Mediterranean coast of Egypt, namely, sand mounds and coastal sand planes and dunes. In addition, a total of 14 heavy minerals found in the soils were characterized. The soil to plant transfer of uranium and thorium was tested on three black sand species, namely, Cakile maritima Scop., Senecio glaucus L. and Rumex Pictus Forssk. The transfer of thorium and uranium radionuclides from the soil to plant is complex process that is subjected to many variables; among which are the organic matter and clay content of the soil, the type of radionuclides and plant species. The study revealed a strong negative relationship between uranium and thorium uptake by S. glaucus and R. pictus and the clay and organic matter content of soil. Concentration of thorium in the soil has a negative correlation with soil-to-plant transfer factor. The study results suggest the possibility of using black sand species for phytoremediation of soils contaminated with radioactive elements. The potentiality of S. glaucus as phytoremediator of radionuclides polluted soils is greater than R. pictus which in turn outweigh C. maritima. PMID:21598782

Hegazy, A K; Emam, M H

2011-02-01

9

Predicting soil-to-plant transfer of radionuclides with a mechanistic model (BioRUR).  

PubMed

BioRUR model has been developed for the simulation of radionuclide (RN) transfer through physical and biological compartments, based on the available information on the transfer of their nutrient analogues. The model assumes that radionuclides are transferred from soil to plant through the same pathways as their nutrient analogues, where K and Ca are the analogues of Cs and Sr, respectively. Basically, the transfer of radionuclide between two compartments is calculated as the transfer of nutrient multiplied by the ratio of concentrations of RN to nutrient, corrected by a selectivity coefficient. Hydroponic experiments showed the validity of this assumption for root uptake of Cs and Sr and reported a selectivity coefficient around 1.0 for both. However, the application of this approach to soil-to-plant transfer raises some questions on which are the effective concentrations of RN and nutrient detected by the plant uptake mechanism. This paper describes the evaluation of two configurations of BioRUR, one which simplifies the soil as an homogeneous pool, and the other which considers that some concentration gradients develop around roots and therefore ion concentrations at the root surface are different from those of the bulk soil. The results show a good fit between the observed Sr transfer and the mechanistic simulations, even when a homogeneous soil is considered. On the other hand, Cs transfer is overestimated by two orders of magnitude if the development of a decreasing K profile around roots is not taken into account. PMID:18261831

Casadesus, J; Sauras-Yera, T; Vallejo, V R

2008-05-01

10

Soil-to-plant transfer of radiocaesium for selected tropical plant species in Bangladesh.  

PubMed

Soil-to-plant transfer factors (TF) of radiocaesium (137Cs) were determined under field condition for grassy vegetation grown in Bangladesh at contaminated land in the Atomic Energy Research Establishment (AERE) campus. TF values for rice, grass and grassy/root vegetations grown in the same type of soil were also measured under pot condition. TF values of 137Cs for grassy vegetation (2.4 x 10(-2) -4.2 x 10(-2) with an average of 3.1 x 10(-2) +/-0.005) obtained under field condition were slightly lower than the values for grass and grassy/root vegetations (2.9 x 10(-2) -6.6 x 10(-2) with an average of 4.8 x 10(-2) +/-0.01 for grass and grassy vegetations and 2.3 x 10(-2) -5.6 x 10(-2) with an average of 4.0 x 10(-2) +/-0.009 for root vegetations, respectively) obtained under pot condition. However, TF values (9.0 x 10(-3) -2.6 x 10(-2) with an average of 1.9 x 10(-2) +/-0.004) obtained for rice were about a factor of 4 lower than the values obtained for grass and grassy/root vegetations. When the properties of the AERE soils as input parameters were used in the soil-plant transfer model of Absalom, the estimated TF values (4.5 x 10(-2) -6.7 x 10(-2) with an average of 5.3 x 10(-2) +/-0.006) were consistent with the measured values obtained for grass and grassy vegetations under pot condition, however, the model overestimates the TF values for rice. PMID:15923070

Rahman, M M; Rahman, M M; Koddus, A; Ahmad, G U; Voigt, G

2005-01-01

11

Soil-to-plant concentration factor and dependence on soil parameters  

Microsoft Academic Search

The soil-to-plant concentration factor of caesium-137 is extremely variable depending on crop type, various interrelated soil parameters and environmental factors. A field study was conducted to determine the concentration factors for principal crops, e.g. potatoes, grain, olives and grass, and soil types of the plains physiographic region of the counties Achaia and Ilia in southwestern Peloponnesus, Greece. Results for 1987,

E. A. Maraziotis

1992-01-01

12

Soil-to-plant transfer of elements is not linear: Results for five elements relevant to radioactive waste in five boreal forest species.  

PubMed

Element-specific concentration ratios (CRs) assuming that plant uptake of elements is linear are commonly used in radioecological modelling to describe the soil-to-plant transfer of elements. The goal of this study was to investigate the validity of the linearity assumption in boreal forest plants, for which only limited relevant data are available. The soil-to-plant transfer of three essential (Mo, Ni, Zn) and two non-essential (Pb, U) elements relevant to the safety of radioactive waste disposal was studied. Three understory species (blueberry, narrow buckler fern and May lily) and two tree species (Norway spruce and rowan) were included. Examining CRs as a function of soil concentration showed that CR was not constant but decreased with increasing soil concentrations for all elements and plant species. A non-linear equation fitted fairly well with the empirical data; the R(2)-values for this equation were constantly higher than those for the linear fit. The difference between the two fits was most evident at low soil concentrations where the use of constant CRs underestimated transfer from soil to plants. Site-specific factors affected the transfer of Mo and Ni. The results suggested that systematic variation with soil concentrations explains a part of the large variation of empirically determined CRs, and the accuracy of modelling the soil-to-plant transfer might be improved by using non-linear methods. Non-linearity of soil-to-plant transfer has been previously reported for a few different species, elements and environments. The present study systematically tested the linearity assumption for five elements (both essential and non-essential) and in five boreal forest species representing different growth traits and phylogenies. The data supported non-linearity in all cases. PMID:21986181

Tuovinen, Tiina S; Roivainen, Päivi; Makkonen, Sari; Kolehmainen, Mikko; Holopainen, Toini; Juutilainen, Jukka

2011-12-01

13

No Significant Contribution of Arbuscular Mycorrhizal Fungi to Transfer of Radiocesium from Soil to Plants  

PubMed Central

The diffuse pollution by fission and activation products following nuclear accidents and weapons testing is of major public concern. Among the nuclides that pose a serious risk if they enter the human food chain are the cesium isotopes 137Cs and 134Cs (with half-lives of 30 and 2 years, respectively). The biogeochemical cycling of these isotopes in forest ecosystems is strongly affected by their preferential absorption in a range of ectomycorrhiza-forming basidiomycetes. An even more widely distributed group of symbiotic fungi are the arbuscular mycorrhizal fungi, which colonize most herbaceous plants, including many agricultural crops. These fungi are known to be more efficient than ectomycorrhizas in transporting mineral elements from soil to plants. Their role in the biogeochemical cycling of Cs is poorly known, in spite of the consequences that fungal Cs transport may have for transfer of Cs into the human food chain. This report presents the first data on transport of Cs by these fungi by use of radiotracers and compartmented growth systems where uptake by roots and mycorrhizal hyphae is distinguished. Independent experiments in three laboratories that used different combinations of fungi and host plants all demonstrated that these fungi do not contribute significantly to plant uptake of Cs. The implications of these findings for the bioavailability of radiocesium in different terrestrial ecosystems are discussed. PMID:15528513

Joner, E. J.; Roos, P.; Jansa, J.; Frossard, E.; Leyval, C.; Jakobsen, I.

2004-01-01

14

Comparative Analysis Of 226Ra Soil-To-Plant Transfer In Cabbage Grown In Various Regions  

NASA Astrophysics Data System (ADS)

The transfer of 226Ra from soil to cabbage was compared amongst regions, namely the surroundings of Urgeiriça uranium milling tailings (GE), regions with past uranium mining activities (GN1), and regions with no uranium mining activities and no uranium deposits (GN2). Results show a slight increase of the concentration ratio values at low radium concentration in soils. Statistical analysis of the mean 226Ra activity concentrations in soil and cabbage for the three regions was carried out. The comparison of 226Ra activity concentrations in soils indicated no difference (p>0.05), between GE and GN2 and significant differences (p<0.05) between GE and GN1 and between GN1 and GN2. Similar statistical results were obtained for 226Ra activity concentrations in cabbage from the same regions. It was concluded that radium Concentration Ratio (CR) for cabbage grown in the region of the main uranium milling site (GE) is of the same order of magnitude of CR in cabagge grown in background regions (GN2). However, 226Ra CR was higher in cabagge from the region with past uranium mining activities (GN1).

Madruga, M. J.; Carvalho, F. P.; Silva, L.; Gouveia, J.

2008-08-01

15

Toward a theory of the effect of inhibition of the transfer of radionuclides and heavy metals from soil to plants by ameliorants. 1. Formulation of the problem  

NASA Astrophysics Data System (ADS)

The effect of an ameliorant on soil and plants is characterized. A model of convective diffusion transfer of nutrition elements from the soil to plants is substantiated. Experimental results that determine a decrease in the ion diffusion coefficients in soil after the application of an ameliorant are presented.

Olodovskii, P. P.

1995-11-01

16

Transfer factor.  

PubMed

Transfer factor, a natural substance of the immune system, was discovered in 1949. More than 3,000 scientific articles have established it as an effective treatment for many diseases, usually those related to the immune system. In China, more than six million people have used transfer factor as a prophylaxis for hepatitis. Information on ordering articles on transfer factor, olive leaf extract, and coconut oil is included. PMID:11366549

1998-01-01

17

ASSESSMENT OF METAL TRANSFER FACTOR UNDER IRRIGATION WITH TREATED MUNICIPAL WASTEWATER  

Microsoft Academic Search

The knowledge of the optimum transfer factor (TF) of heavy metals from soil to plant is of vital importance, because TF is an indicator of heavy metal mobility in soils and a factor that quantifies the existing differences in the bioavailability of metals to plants. Optimum heavy metal transfer factors were found multiple linear regression analysis (MLRA), under the effect

Ioannis K. Kalavrouziotis; Prodromos Koukoulakis; Eirini Kostakioti

18

Transfer Factors for Contaminant Uptake by Fruit and Nut Trees  

SciTech Connect

Transfer of radionuclides from soils into plants is one of the key mechanisms for long-term contamination of the human food chain. Nearly all computer models that address soil-to-plant uptake of radionuclides use empirically-derived transfer factors to address this process. Essentially all available soil-to-plant transfer factors are based on measurements in annual crops. Because very few measurements are available for tree fruits, samples were taken of alfalfa and oats and the stems, leaves, and fruits and nuts of almond, apple, apricot, carob, fig, grape, nectarine, pecan, pistachio (natural and grafted), and pomegranate, along with local surface soil. The samples were dried, ground, weighed, and analyzed for trace constituents through a combination of induction-coupled plasma mass spectrometry and instrumental neutron activation analysis for a wide range of naturally-occurring elements. Analysis results are presented and converted to soil-to-plant transfer factors. These are compared to commonly used and internationally recommended values. Those determined for annual crops are very similar to commonly-used values; those determined for tree fruits show interesting differences. Most macro- and micronutrients are slightly reduced in fruits; non-essential elements are reduced further. These findings may be used in existing computer models and may allow development of tree-fruit-specific transfer models.

Napier, Bruce A.; Fellows, Robert J.; Minc, Leah D.

2013-11-20

19

The Transfer of Dissolved Cs-137 from Soil to Plants  

SciTech Connect

Rapidly maturing plants were grown simultaneously at the same experimental sites under natural conditions at the Chernobyl Exclusion Zone. Roots of the plants were side by side in the soil. During two seasons we selected samples of the plants and of the soils several times every season. Content of Cs-137 in the plant and in the soil solution extracted from the samples of soils was measured. Results of measurements of the samples show that, for the experimental site, Cs-137 content in the plant varies with date of the sample selection. The plant:soil solution Cs-137 concentration ratio depends strongly on the date of selection and also on the type of soil. After analysis of the data we conclude that Cs-137 plant uptake is approximately proportional to the content of dissolved Cs-137 in the soil per unit of volume, and the plant:soil solution Cs-137 concentration ratio for the soil is approximately proportional to the soil moisture. (authors)

Prorok, V.V.; Melnichenko, L.Yu. [Department of Physics, Taras Shevchenko National University of Kyiv, 2, build. 1 Acad. Glushkov prospect, Kyiv-680 MSP (Ukraine); Mason, C.F.V. [Research Applications Corporation, 148 Piedra Loop, Los Alamos, NM 87544 (United States); Ageyev, V.A.; Ostashko, V.V. [Institute for Nuclear Research, 47 Nauky prospect, Kyiv-680 MSP (Ukraine)

2006-07-01

20

Soil-to-Plant Concentration Ratios for Assessing Food Chain Pathways in Biosphere Models  

SciTech Connect

This report describes work performed for the U.S. Nuclear Regulatory Commission’s project Assessment of Food Chain Pathway Parameters in Biosphere Models, which was established to assess and evaluate a number of key parameters used in the food-chain models used in performance assessments of radioactive waste disposal facilities. Section 2 of this report summarizes characteristics of samples of soils and groundwater from three geographical regions of the United States, the Southeast, Northwest, and Southwest, and analyses performed to characterize their physical and chemical properties. Because the uptake and behavior of radionuclides in plant roots, plant leaves, and animal products depends on the chemistry of the water and soil coming in contact with plants and animals, water and soil samples collected from these regions of the United States were used in experiments at Pacific Northwest National Laboratory to determine radionuclide soil-to-plant concentration ratios. Crops and forage used in the experiments were grown in the soils, and long-lived radionuclides introduced into the groundwater provide the contaminated water used to water the grown plants. The radionuclides evaluated include 99Tc, 238Pu, and 241Am. Plant varieties include alfalfa, corn, onion, and potato. The radionuclide uptake results from this research study show how regional variations in water quality and soil chemistry affect radionuclide uptake. Section 3 summarizes the procedures and results of the uptake experiments, and relates the soil-to-plant uptake factors derived. In Section 4, the results found in this study are compared with similar values found in the biosphere modeling literature; the study’s results are generally in line with current literature, but soil- and plant-specific differences are noticeable. This food-chain pathway data may be used by the NRC staff to assess dose to persons in the reference biosphere (e.g., persons who live and work in an area potentially affected by radionuclide releases) of waste disposal facilities and decommissioning sites.

Napier, Bruce A.; Fellows, Robert J.; Krupka, Kenneth M.

2007-10-01

21

Transfer Factors for Contaminant Uptake  

E-print Network

Transfer Factors for Contaminant Uptake by Fruit and Nut Trees Office of Nuclear Regulatory of supply, upon written request as follows: Address: U.S. Nuclear Regulatory Commission Office thereof, nor any employee, makes any warranty, expressed or implied, or assumes any legal liability

22

Nickel and manganese transfer from soil to plant in lateritic mining soils from New Caledonia  

NASA Astrophysics Data System (ADS)

New Caledonian ferritic soils (more than 50 % of iron) are naturally rich in metals (chromium, nickel, cobalt, and manganese), deficient in major nutrients (nitrogen, phosphorous, and potassium), and unbalanced for the calcium/magnesium ratio. Under these particular ecological conditions, New Caledonia, recognized as a hot-spot of biodiversity, is a natural laboratory to study and understand the adaptation strategies of plants to metalliferous soils, and particularly the tolerance and (hyper)accumulation of metals by plants. Moreover, understanding such mechanisms is essential to develop rehabilitation or phytoremediation techniques for polluted soils, as well as phytomining techniques. Thus, in order to understand the soil - plant relationship and metal mobility along a toposequence in a future nickel mining massif, field experiments were conducted in an isolated ultramafic massif of New Caledonia. Several plant species of two endemic and frequent plant genera were chosen: Tristaniopsis guillainii and T. calobuxus (Myrtaceae), and Phyllanthus serpentinus and P. favieri (Euphorbiaceae), because of their nickel and/or manganese accumulating or hyperaccumulating nature. Leaves, twigs, and roots of all plants were collected along the soil sequence and their associated rhizospheric and bulk soils were sampled. Next, a series of characterization techniques were adapted and then coupled to cryogenics. The combined use of those multiple techniques (cryo-microtomy, cryo-SEM, µXRF, cryo-XAS, and soil characterization) allowed to study co-location and speciation of nickel and manganese in the different plant organs and soils (rhizospheric and bulk). Bioaccumulated nickel and manganese had different distribution patterns. In leaves, Ni accumulated in non photosynthetic tissues (e.g. epidermis) whereas Mn preferentially accumulated in mesophyll whatever the plant species. Nevertheless, in spite of a different speciation in soils, nickel and manganese were both found as similar divalent organometallic complexes in the different plant parts.

Pouschat, P.; Rose, J.; Alliot, I.; Dominici, C.; Keller, C.; Laffont-Schwob, I.; Olivi, L.; Ambrosi, J.-P.

2009-04-01

23

Literature Review and Assessment of Plant and Animal Transfer Factors Used in Performance Assessment Modeling  

SciTech Connect

A literature review and assessment was conducted by Pacific Northwest National Laboratory (PNNL) to update information on plant and animal radionuclide transfer factors used in performance-assessment modeling. A group of 15 radionuclides was included in this review and assessment. The review is composed of four main sections, not including the Introduction. Section 2.0 provides a review of the critically important issue of physicochemical speciation and geochemistry of the radionuclides in natural soil-water systems as it relates to the bioavailability of the radionuclides. Section 3.0 provides an updated review of the parameters of importance in the uptake of radionuclides by plants, including root uptake via the soil-groundwater system and foliar uptake due to overhead irrigation. Section 3.0 also provides a compilation of concentration ratios (CRs) for soil-to-plant uptake for the 15 selected radionuclides. Section 4.0 provides an updated review on radionuclide uptake data for animal products related to absorption, homeostatic control, approach to equilibration, chemical and physical form, diet, and age. Compiled transfer coefficients are provided for cow’s milk, sheep’s milk, goat’s milk, beef, goat meat, pork, poultry, and eggs. Section 5.0 discusses the use of transfer coefficients in soil, plant, and animal modeling using regulatory models for evaluating radioactive waste disposal or decommissioned sites. Each section makes specific suggestions for future research in its area.

Robertson, David E.; Cataldo, Dominic A.; Napier, Bruce A.; Krupka, Kenneth M.; Sasser, Lyle B.

2003-07-20

24

Factors affecting hispanic student transfer behavior  

Microsoft Academic Search

Few studies examine transfer of nontraditional-age Hispanic community college students to four-year institutions. The present study examined attitudes, cognitive and noncognitive experiences, and transfer-related behaviors of students (N=277) who graduated from one two-year institution, in order to determine factors associated with successful transfer and make appropriate policy recommendations. An undergraduate survey based on Tinto's (1975, 1987) conceptual framework and Cabrera,

Barbara A. Kraemer

1995-01-01

25

Transfer of Radium226 from Soil to Rice: A Comparison of Sampling Area Differences  

Microsoft Academic Search

Due to limited numbers of radium-226 (Ra) soil-to-plant transfer data, it has been difficult to analyze the sampling area differences. In this study, we measured Ra concentrations in brown rice and associated soils collected from 61 locations throughout Japan and obtained soil-to-rice transfer factors (TFs). Concentrations of Ra in the soils collected in southwestern Japan were higher than those in

Shigeo UCHIDA; Keiko TAGAMI

2009-01-01

26

Soil-to-root vegetable transfer factors for (226)Ra, (232)Th, (40)K, and (88)Y in Malaysia.  

PubMed

Soil-to-plant transfer factors (TFs) are of fundamental importance in assessing the environmental impact due to the presence of radioactivity in soil and agricultural crops. Tapioca and sweet potato, both root crops, are popular foodstuffs for a significant fraction of the Malaysian population, and result in intake of radionuclides. For the natural field conditions experienced in production of these foodstuffs, TFs and the annual effective dose were evaluated for the natural radionuclides (226)Ra, (232)Th, (40)K, and for the anthropogenic radionuclide (88)Y, the latter being a component of fallout. An experimental tapioca field was developed for study of the time dependence of plant uptake. For soil samples from all study locations other than the experimental field, it has been shown that these contain the artificial radionuclide (88)Y, although the uptake of (88)Y has only been observed in the roots of the plant Manihot esculenta (from which tapioca is derived) grown in mining soil. The estimated TFs for (226)Ra and (232)Th for tapioca and sweet potato are very much higher than that reported by the IAEA. For all study areas, the annual effective dose from ingestion of tapioca and sweet potato are estimated to be lower than the world average (290 ?Sv y(-1)). PMID:24814722

Asaduzzaman, Kh; Khandaker, Mayeen Uddin; Amin, Y M; Bradley, D A; Mahat, R H; Nor, R M

2014-09-01

27

From soil to plant, the journey of P through trophic relationships and ectomycorrhizal association  

PubMed Central

Phosphorus (P) is essential for plant growth and productivity. It is one of the most limiting macronutrients in soil because it is mainly present as unavailable, bound P whereas plants can only use unbound, inorganic phosphate (Pi), which is found in very low concentrations in soil solution. Some ectomycorrhizal fungi are able to release organic compounds (organic anions or phosphatases) to mobilize unavailable P. Recent studies suggest that bacteria play a major role in the mineralization of nutrients such as P through trophic relationships as they can produce specific phosphatases such as phytases to degrade phytate, the main form of soil organic P. Bacteria are also more effective than other microorganisms or plants at immobilizing free Pi. Therefore, bacterial grazing by grazers, such as nematodes, could release Pi locked in bacterial biomass. Free Pi may be taken up by ectomycorrhizal fungus by specific phosphate transporters and transferred to the plant by mechanisms that have not yet been identified. This mini-review aims to follow the phosphate pathway to understand the ecological and molecular mechanisms responsible for transfer of phosphate from the soil to the plant, to improve plant P nutrition. PMID:25360140

Becquer, Adeline; Trap, Jean; Irshad, Usman; Ali, Muhammad A.; Claude, Plassard

2014-01-01

28

Confirmatory Factor Analysis of Transfer Student Adjustment  

ERIC Educational Resources Information Center

Transfer students' adjustment to college has received substantial attention by researchers. This focus has predominately investigated the observation of "transfer shock": a decrease in grade point average (GPA) experienced after transferring. In response to the persistent focus on transfer shock, growing attention has been directed…

Young, Jacob T. N.; Litzler, Elizabeth

2013-01-01

29

Transfer of Radionuclides K-40, Th-232 and Ra-226 from Mining Soil to Sawi (Japanese Mustard)  

SciTech Connect

The uptake of naturally occurring thorium, radium and potassium by sawi (Japanese Mustard) from disused tin mining was studied. Both soil and sawi sample were collected from a vegetable farm located 15 km from Kuala Lumpur, Malaysia where the farm has been operating for 22 years on a disused tin mining. By using a gamma spectroscopy system, the transfers of radionuclides from soil to plants were investigated. The highest values of radionuclides in the soil was K-40 which is 52.8 Bq kg{sup -1} and the lowest was Ra-226 which is 6.51 Bq kg{sup -1}. The activity of Th-232 is 18.5 Bq kg{sup -1}. The activity of radionuclides in the sawi sample shows higher values as compared to the soil sample. The highest values of radionuclides in the sawi were K-40 which is 446 Bq kg{sup -1} and the lowest was Ra-226 which is 17.5 Bq kg{sup -1}. The activity of Th-232 is 65.2 Bq kg{sup -1}. The concentration of radionuclides in soils and plants can be used for the determination of soil-to-plant transfer factors. The soil to plant transfer factors (TF) were calculated and observed to be 2.68 for radium-226, 3.52 for thorium-232 and the highest which is 3.97 for potassium-40.

Hariandra, M.; Amin, Y. M. [Radiation Laboratory, Physics Department, University of Malaya, 59100, Kuala Lumpur (Malaysia)

2008-05-20

30

Transfer of Radionuclides K-40, Th-232 and Ra-226 from Mining Soil to Sawi (Japanese Mustard)  

NASA Astrophysics Data System (ADS)

The uptake of naturally occurring thorium, radium and potassium by sawi (Japanese Mustard) from disused tin mining was studied. Both soil and sawi sample were collected from a vegetable farm located 15 km from Kuala Lumpur, Malaysia where the farm has been operating for 22 years on a disused tin mining. By using a gamma spectroscopy system, the transfers of radionuclides from soil to plants were investigated. The highest values of radionuclides in the soil was K-40 which is 52.8 Bq kg-1 and the lowest was Ra-226 which is 6.51 Bq kg-1. The activity of Th-232 is 18.5 Bq kg-1. The activity of radionuclides in the sawi sample shows higher values as compared to the soil sample. The highest values of radionuclides in the sawi were K-40 which is 446 Bq kg-1 and the lowest was Ra-226 which is 17.5 Bq kg-1. The activity of Th-232 is 65.2 Bq kg-1. The concentration of radionuclides in soils and plants can be used for the determination of soil-to-plant transfer factors. The soil to plant transfer factors (TF) were calculated and observed to be 2.68 for radium-226, 3.52 for thorium-232 and the highest which is 3.97 for potassium-40.

Hariandra, M.; Amin, Y. M.

2008-05-01

31

Electronic and Nuclear Factors in Charge and Excitation Transfer  

SciTech Connect

We report the and/or state of several subprojects of our DOE sponsored research on Electronic and Nuclear Factors in Electron and Excitation Transfer: (1) Construction of an ultrafast Ti:sapphire amplifier. (2) Mediation of electronic interactions in host-guest molecules. (3) Theoretical models of electrolytes in weakly polar media. (4) Symmetry effects in intramolecular excitation transfer.

Piotr Piotrowiak

2004-09-28

32

A Compendium of Transfer Factors for Agricultural and Animal Products  

SciTech Connect

Transfer factors are used in radiological risk assessments to estimate the amount of radioactivity that could be present in a food crop or organism based on the calculated concentration in the source medium (i.e., soil or animal feed). By calculating the concentration in the food, the total intake can be estimated and a dose calculated as a result of the annual intake. This report compiles transfer factors for radiological risk assessments, using common food products, including meats, eggs, and plants. Transfer factors used were most often selected from recommended values listed by national or international organizations for use in radiological food chain transport calculations. Several methods of estimation and extrapolation were used for radionuclides not listed in the primary information sources. Tables of transfer factors are listed by element and information source for beef, eggs, fish, fruit, grain, leafy vegetation, milk, poultry, and root vegetables.

Staven, Lissa H.; Napier, Bruce A.; Rhoads, Kathleen; Strenge, Dennis L.

2003-06-02

33

Neutron Spectroscopic Factors from Transfer Reactions  

E-print Network

The present paper examines past measurements of the angular distributions for (d,p) and (p,d) reactions on targets with Z=3-24 leading to the ground states. The procedure is prescribed for extracting a conventional set of spectroscopic factors. Most of these spectroscopic factors agree well with large-basis shell model predictions. In all, the ground state neutron spectroscopic factors for 80 nuclei have been obtained. The consistency of the method is evaluated by comparing spectroscopic factors obtained separately in (p,d) and (d,p) reactions. The values correlate with Endt's compilation when available, but the current method is more general and the spectroscopic factor values obtained are more consistent with each other.

Jenny Lee; M. B. Tsang; W. G. Lynch

2006-02-19

34

Factors affecting the transfer of organochlorine pesticide residues to breastmilk  

Microsoft Academic Search

Existing studies monitoring organochlorine pesticide residues in breastmilk were examined to identify whether common factors determine the extent of transfer of these residues. A structured review of the English language literature was conducted. Papers were reviewed and assessed using a structured protocol. A total of 77 papers were initially identified, 46 of which contained conclusions relating to the factors which

Caroline A. Harris; Michael W. Woolridge; Alastair W. M. Hay

2001-01-01

35

Mechanisms of pulmonary transfer factor decline following heart transplantation  

Microsoft Academic Search

Objective: Although the decline in the pulmonary transfer factor (TLCO) following heart transplantation is well documented, the causes and mechanisms of this decline remain unknown. The aim of this study was to determine the relative contribution of each of TLCO components (the diffusing capacity of the alveolar-capillary membrane (DM), the pulmonary capillary blood volume (VC) and haemoglobin concentration) to TLCO

O. A. Al-Rawas; R. Carter; R. D. Stevenson; S. K. Naik; D. J. Wheatley

2000-01-01

36

Neutron spectroscopic factors of Ni isotopes from transfer reactions  

E-print Network

177 neutron spectroscopic factors for nickel isotopes have been extracted by performing a systematic analysis of the angular distributions measured from (d,p) transfer reactions. A subset of the extracted spectroscopic factors are compared to predictions of large-basis shell models in the full pf model space using the GXPF1A effective interaction, and the (f5/2, p3/2, p1/2, g9/2) model space using the JJ4PNA interaction. For ground states, the predicted spectroscopic factors using the GXPF1A effective interaction in the full pf model space agree very well with the experimental values, while predictions based on several other effective interactions and model spaces are about 30% higher than the experimental values. For low-energy excited states (spectroscopic factors and shell model calculations is not better than a factor of two.

Jenny Lee; M. B. Tsang; W. G. Lynch; M. Horoi; S. C. Su

2009-05-07

37

Tests of transfer reaction determinations of astrophysical S factors  

E-print Network

involve radioactive targets which makes measurements quite difficult or even impossible using conventional methods. Hence techniques have been developed to determine rates by indirect methods. For example, precise information on excitation energies.... The advantage of the ANC approach is that it provides a method to determine direct capture S factors accurately from the results of nuclear reactions such as peripheral nucleon transfer which can be studied with radioactive beams and have cross sections...

Gagliardi, Carl A.; Tribble, Robert E.; Azhari, A.; Clark, HL; Lui, YW; Mukhamedzhanov, AM; Sattarov, A.; Trache, L.; Burjan, V.; Cejpek, J.; Kroha, V.; Piskor, S.; Vincour, J.

1999-01-01

38

Consistency in Quenching of ``Absolute'' Spectroscopic Factors from Transfer Reactions  

NASA Astrophysics Data System (ADS)

The strengths of single-particle transitions in (e,e'p) knockout reactions on closed-shell nuclei are lower than expected,footnotetextG. J. Kramer et al., Nucl. Phys. A679, 267 (2001). due to limitations of the mean-field description imposed by correlations. This quenching of single-particle strength by ˜0.5 appeared to be a general property of nuclei from ^16O to ^208Pb. In our work, the combined sums of neutron-adding and neutron-removing strengths from (d,p) and (p,d) transfer reactions on four Ni isotopes yield very similar quenching factors of ˜0.53 (varying by ˜10% with reasonable choices of optical-model parameters).footnotetextJ. P. Schiffer et al., Phys. Rev. Lett. 108, 022501 (2012). Recently, spectroscopic overlaps between ^4He and ^3He were extracted from GFMC calculations.footnotetextI. Brida et al., Phys. Rev. C 84, 024319 (2011). With these, our data on (?,^3He) and (^3He,?) on the Ni isotopes yields ˜0.62. Additional data for proton transfer on Ni and transfer on other nuclei are also being analyzed. This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357 and the U.K. Science and Technology Facilities Council.

Schiffer, J. P.; Kay, B. P.; Freeman, S. J.

2013-04-01

39

Factors affecting the efficiency of embryo transfer in the domestic ferret (Mustela putorius furo)  

E-print Network

Factors affecting the efficiency of embryo transfer in the domestic ferret (Mustela putorius furo 19 July 2005; accepted 30 October 2005 Abstract Embryo transfer (ET) to recipient females of transferred embryo were investigated. Unilateral and bilateral transfer of zygotes or blastocysts

Engelhardt, John F.

40

AIDS and transfer factor: myths, certainties and realities.  

PubMed

At the end of the 20th century, the triumph of biology is as indisputable as that of physics was at the end of the 19th century, and so is the might of the inductive thought. Virtually all diseases have been seemingly conquered and HIV, the cause of AIDS, has been fully described ten years after the onset of the epidemic. However, the triumph of biological science is far from being complete. The toll of several diseases, such as cancer, continues to rise and the pathogenesis of AIDS remains elusive. In the realm of inductive science, the dominant paradigm can seldom be challenged in a frontal attack, especially when it is apparently successful, and only what Kuhn calls "scientific revolutions" can overthrow it. Thus, it is hardly surprising that the concept of transfer factor is considered with contempt, and the existence of the moiety improbable: over forty years after the introduction of the concept, not only its molecular structure remains unknown, but also its putative mode of action contravenes dogmas of both immunology and molecular biology. And when facts challenge established dogmas, be in religion, philosophy or science, they must be suppressed. Thus, results of heterodox research become henceforth nisi-i.e., valid unless cause is shown for rescinding them, because they challenge the prevalent paradigm. However, when observations pertain to lethal disorders, their suppression in the name of dogmas may become criminal. Because of the failure of medical science to manage the AIDS pandemic, transfer factor, which has been successfully used for treating or preventing viral infections, may today overcome a priori prejudice and rejection more swiftly. In science, as in life, certainties always end up by dying, and Copernicus' vision by replacing that of Ptolemy. PMID:8993753

Viza, D

1996-01-01

41

Structural factors influencing the intramolecular charge transfer and photoinduced electron transfer in tetrapyrazinoporphyrazines.  

PubMed

A series of unsymmetrical tetrapyrazinoporphyrazines (TPyzPzs) from the group of azaphthalocyanines with one peripherally attached amino substituent (donor) were synthesized, and their photophysical properties (fluorescence quantum yield and singlet oxygen quantum yield) were determined. The synthesized TPyzPzs were expected to undergo intramolecular charge transfer (ICT) as the main pathway for deactivating their excited states. Several structural factors were found to play a critical role in ICT efficiency. The substituent in the ortho position to the donor center significantly influences the ICT, with tert-butylsulfanyl and butoxy substituents inducing the strongest ICTs, whereas chloro, methyl, phenyl, and hydrogen substituents in this position reduce the efficiency. The strength of the donor positively influences the ICT efficiency and correlates well with the oxidation potential of the amines used as the substituents on the TPyzPz as follows: n-butylamine < N,N-diethylamine < aniline < phenothiazine. The ICT (with conjugated donors and acceptors) in the TPyzPz also proved to be much stronger than a photoinduced electron transfer in which the donor and the acceptor are connected through an aliphatic linker. PMID:24509513

Novakova, Veronika; Hladík, Petr; Filandrová, Tereza; Zajícová, Ivana; Krepsová, Veronika; Miletin, Miroslav; Len?o, Juraj; Zimcik, Petr

2014-03-21

42

Measured elemental transfer factors for boreal hunter\\/gatherer scenarios: fish, game and berries  

Microsoft Academic Search

The environmental assessment of long-term nuclear waste management requires data to estimate food chain transfers for radionuclides in various environmental settings. For key elements such as iodine (I) and chlorine (Cl), there is a paucity of transfer factor data, particularly outside of agricultural food chains. This study dealt with transfers of I, Cl and 28 other elements to foods that

S. C. Sheppard; J. M. Long; B. Sanipelli

2010-01-01

43

Factors in the Transfer of Governance-Facilitation Skills within Farmers' Marketing Organizations in Uganda  

ERIC Educational Resources Information Center

Purpose: Training transfer has been examined for formal industrial and service organizations in developed countries but rarely for rural organizations in sub-Saharan Africa. This study sought to identify transfer system factors that best explain the transfer of governance-facilitation skills provided to leaders of farmers' marketing organizations…

Miiro, Richard F.; Mazur, Robert E.; Matsiko, Frank B.

2012-01-01

44

Student Perceptions of Factors Contributing to Community-College-to-University Transfer Success  

ERIC Educational Resources Information Center

The transfer process includes areas such as academic preparation and advisement, transfer evaluation, financial aid, and psychosocial factors. A descriptive, exploratory method was employed to capture the perceptions of a transfer student cohort regarding their experiences in transitioning from lower division community college enrollment to…

Gard, Dwight R.; Paton, Valerie; Gosselin, Kevin

2012-01-01

45

Relationship between the radiocesium interception potential and the transfer of radiocesium from soil to soybean cultivated in 2011 in Fukushima Prefecture, Japan.  

PubMed

The concentration of radiocesium ((134)Cs and (137)Cs) in agricultural fields around Fukushima Dai-ichi Nuclear Power Plant (FDNPP) was elevated after the accident in March 2011. Evaluation of soil properties that influence phytoavailability of radiocesium is important for optimal soil management to minimize radiocesium transfer to crops. In this study, soybean grain and soil samples (0-15 cm) were collected from 46 locations in Fukushima Prefecture in 2011, and (137)Cs concentrations were measured. (137)Cs concentration ranges were 11-329 Bq kg(-1)-dry in soybean grain samples, and 0.29-2.49 kBq kg(-1)-dry in soil samples. The radiocesium interception potential (RIP) values in the soil samples ranged from 0.30 to 8.61 mol kg(-1). RIP negatively correlated with total carbon content and oxalate-extractable Si and Al + 1/2 Fe in the soils, suggesting that soils rich in organic matter and poorly crystalline clays tended to have lower RIP in this region. The soil-to-plant transfer factor for (137)Cs, analyzed in relation with various soil characteristics, varied by two orders of magnitude and was significantly negatively correlated with RIP and exchangeable K concentration in soil. The results show that RIP is useful for evaluating the efficiency of radiocesium transfer from soil to plants in this region. PMID:25036920

Takeda, Akira; Tsukada, Hirofumi; Yamaguchi, Noriko; Takeuchi, Megumi; Sato, Mutsuto; Nakao, Atsushi; Hisamatsu, Shun'ichi

2014-11-01

46

Factors Affecting the Development of Somatic Cell Nuclear Transfer Embryos in Cattle  

PubMed Central

Nuclear transfer is a complex multistep procedure that includes oocyte maturation, cell cycle synchronization of donor cells, enucleation, cell fusion, oocyte activation and embryo culture. Therefore, many factors are believed to contribute to the success of embryo development following nuclear transfer. Numerous attempts to improve cloning efficiency have been conducted since the birth of the first sheep by somatic cell nuclear transfer. However, the efficiency of somatic cell cloning has remained low, and applications have been limited. In this review, we discuss some of the factors that affect the developmental ability of somatic cell nuclear transfer embryos in cattle. PMID:25341701

AKAGI, Satoshi; MATSUKAWA, Kazutsugu; TAKAHASHI, Seiya

2014-01-01

47

Adenoviral Gene Transfer of Connective Tissue Growth Factor in the Lung Induces Transient Fibrosis  

Microsoft Academic Search

Connective tissue growth factor (CTGF) is felt to be one of the key profibrotic factors and is a downstream effector molecule mediating the action of transforming growth factor (TGF)-1, a cytokine known to induce severe and progressive fibrosis. However, the in vivo fibro- genic effect of isolated CTGF expression is not well described. We used adenoviral gene transfer to transiently

Philippe Bonniaud; Peter J. Margetts; Martin Kolb; Thomas Haberberger; Margaret Kelly; Jennifer Robertson; Jack Gauldie

2003-01-01

48

Transitioning Transfer Students: Interactive Factors that Influence First-Year Retention  

ERIC Educational Resources Information Center

This study examined the diverse patterns of interactive factors that influence transfer students' first-year retention at a midsize four-year university. The population for this study consisted of five cohorts totaling 1,713 full-time, degree-seeking transfer students. Sequential sets of logistic regression analyses on blocks of variables were…

Luo, Mingchu; Williams, James E.; Vieweg, Bruce

2007-01-01

49

Gene Ther . Author manuscript Coagulation factor X mediates adenovirus type 5 liver gene transfer in  

E-print Network

Gene Ther . Author manuscript Page /1 4 Coagulation factor X mediates adenovirus type 5 liver gene. Ad5 vectors accumulated in and mediated gene transfer predominantly to the liver while FX-binding ablated vectors primarily targeted the spleen but showed negligible liver gene transfer. Therefore, the Ad

Paris-Sud XI, Université de

50

Simulation of a Wireless Power Transfer System for Electric Vehicles with Power Factor Correction  

SciTech Connect

Wireless power transfer has been a popular topic of recent research. Most research has been done to address the limitations of coil-to-coil efficiency. However, little has been done to address the problem associated with the low input power factor with which the systems operate. This paper details the steps taken to analyze a wireless power transfer system from the view of the power grid under a variety of loading conditions with and without power factor correction.

Pickelsimer, Michael C [ORNL; Tolbert, Leon M [ORNL; Ozpineci, Burak [ORNL; Miller, John M [ORNL

2012-01-01

51

Factors affecting the efficiency of embryo transfer in the domestic ferret (Mustela putorius furo).  

PubMed

Embryo transfer (ET) to recipient females is a foundational strategy for a number of assisted reproductive technologies, including cloning by somatic cell nuclear transfer. In an attempt to develop efficient ET in domestic ferrets, factors affecting development of transferred embryo were investigated. Unilateral and bilateral transfer of zygotes or blastocysts in the oviduct or uterus was evaluated in recipient nulliparous or primiparous females. Developing fetuses were collected from recipient animals 21 days post-copulation and examined. The percentage of fetal formation was different (P<0.05) for unilateral and bilateral transfer of zygotes (71%) in nulliparous females with bilateral transfer (56%) in primiparous recipients. The percentage (90%) of fetal formation in nulliparous recipients following unilateral transfer of blastocysts was higher (P<0.05) than that observed in primiparous recipients with bilateral ET (73%). Notably, the percentage of fetal formation was higher (P<0.05) when blastocyts were transferred as compared to zygotes (90% versus 71%). Transuterine migration of embryos occurred following all unilateral transfers and also in approximately 50% of bilateral transfers with different number of embryos in each uterine horn. These data will help to facilitate the development of assisted reproductive strategies in the ferret and could lead to the use of this species for modeling human disease and for conservation of the endangered Mustelidae species such as black-footed ferret and European mink. PMID:16330092

Li, Ziyi; Sun, Xingshen; Chen, Juan; Leno, Gregory H; Engelhardt, John F

2006-07-15

52

Voltage controllable power factor corrector based inductive coupling power transfer system  

Microsoft Academic Search

This paper proposed a novel inductive coupling power transfer (ICPT) topology to improve the power factor, output voltage regulation and efficiency. The proposed ICPT is mainly constructed by a voltage controllable power factor corrector (VC-PFC) and a LLC resonant circuit. Additionally, the series compensation and series-parallel compensation are used in the primary and the secondary sides of the coupling transformer

Liang-Rui Chen; Hai-Wen Chang; Chia-Hsuan Wu; Chung-Ming Young; Neng-Yi Chu

2012-01-01

53

The form factors of the nucleon at small momentum transfer  

E-print Network

We study the low energy expansion of the nucleon's electroweak form factors in the framework of an effective chiral Lagrangian including pions, nucleons and the $Delta (1232)$. We work to third order in the so-called small scale expansion and compare the results with the ones previously obtained in the chiral expansion. In addition, these calculations serve as a first exploratory study of renormalization and decoupling within the small scale expansion.

Véronique Bernard; Harold W. Fearing; Thomas R. Hemmert; Ulf-G. Meißner

1998-04-28

54

152 factors affecting fertility on an equine embryo transfer program.  

PubMed

Assisted reproduction through embryo transfer (ET) increases the chances, within a limited group of genetically superior mares, producing a greater number of desirable offspring. Several variables, however, are involved in the process and may impact or even limit the potential of ET to increase a single mare´s foal production within a given breeding season. The objective was to analyse information on variables related to an ET operation carried over 10 years by a single veterinarian in different reproduction centers or directly from the database of all breeders. General management and reproductive data from 150 embryo donor mares, 362 recipient mares and 73 stallions were submitted to statistical analysis by the GENMOD procedure using SAS(®) (SAS Institute Inc., Cary, NC, USA). The proportion of positive recoveries (in which one or more embryos were actually recovered) and of pregnant recipients were dependent variables and donor breed (Campolina, Mangalarga, Thoroughbred, Haflinger and Brasileiro de Hipismo), donor (3-18 years old) and stallion age (3-20 years old) type of semen, hormonal ovulation induction (1000-2500IU of hCG when dominant follicles reached at least 30mm in diameter), diameter of the dominant follicles at the time of induction in donors and recipients as independent variables. Gestation rate was greater (P<0.05) for embryos produced by donors of the Campolina breed compared to all others (74.0 v. 57.6%). The positive flush rates of donor age classes ?7 (50.2%), >7 and <12 (60.0%) and ?12 (53.2%) years old were similar (P=0.45). Gestation rates were similar (P=0.43) between stallions <6 (70.3%) and ?6 (75.8%) years-old. The proportion of positive flushes was greater (P=0.01) for fresh semen (59.9%) compared to those of natural service, cooled and frozen-thawed semen (54.8, 51.5 and 28.6%, respectively). Pregnancy rates were similar (P>0.05) between recipient mares hCG-induced (70.6%) and not induced (73.3%) to ovulate. In conclusion, we confirmed that donor breed and type of semen are influential over pregnancy and positive flush rates in the present study. Stallion or donor mare age did not influence fertility traits in this study, which indicates that animals were well managed and used within appropriate age limits. More relevant data may be gathered from the field work of veterinarians in order to enhance the knowledge that supports managing decisions in assisted reproduction techniques. PMID:25472201

Souza, J C; Portilho, R V; Pinto, T L C; Neto, F D M; Filgueiras, E P; Silva, M G C M; Moura, R S

2014-12-01

55

Fertility factors in Pseudomonas putida: selection and properties of high-frequency transfer and chromosome donors.  

PubMed Central

The octane plasmid (OCT) in Pseudomonas putida strains has been shown to be transferred at low frequency. However, bacteria which had newly received this plasmid showed a transient increase in donor ability. Using Octane+ P. putida as the donor, the transfer of most chromosomal markers was shown to be independent of OCT transfer, whereas the mobilization of the octanoate catabolism genes (octanoic and acetate) was dependent on OCT plasmid transfer. The presence of a fertility factor termed FPo has been postulated to explain these results. Strains carrying only this fertility factor have been obtained from strains carrying both OCT and FPo plasmids. Strains in which the OCT plasmid was transferred at high frequencies have also been isolated, and chromosome mobilization by OCT and FPo has been compared. A different gradient of transmission by OCT and FPo has been observed. It has also been shown that chromosome transfer by OCT was dependent on the bacterial recombination system, whereas the chromosome transfer by FPo was unaffected by the presence of a rec mutation in the donor strain. PMID:762014

Hermann, M; Garg, G K; Gunsalus, I C

1979-01-01

56

Accumulation of (137)Cs in Brazilian soils and its transfer to plants under different climatic conditions.  

PubMed

The spatial distribution and behaviour of the global fallout (137)Cs in the tropical, subtropical and equatorial soil-plant systems were investigated at several upland sites in Brazil selected according to their climate characteristics, and to the agricultural importance. To determine the (137)Cs deposition density, undisturbed soil profiles were taken from 23 environments situated between the latitudes of 02 degrees N and 30 degrees S. Sampling sites located along to the equator exhibited (137)Cs deposition densities with an average value of 219Bqm(-2). Extremely low deposition densities of 1.3Bqm(-2) were found in the Amazon region. In contrast, the southern part of Brazil, located between latitudes of 20 degrees S and 34 degrees S, exhibited considerably higher deposition densities ranging from 140Bqm(-2) to 1620Bqm(-2). To examine the (137)Cs soil-to-plant transfer in the Brazilian agricultural products, 29 mainly tropical plant species, and corresponding soil samples were collected at 43 sampling locations in nine federal states of Brazil. Values of the (137)Cs concentration factor plant/soil exhibited a large range from 0.020 (beans) to 6.2 (cassava). Samples of some plant species originated from different collecting areas showed different concentration factors. The (137)Cs content of some plants collected was not measurable due to a very low (137)Cs concentration level found in the upper layers of the incremental soils. Globally, the soil-to-plant transfer of (137)Cs can be described by a logarithmic normal distribution with a geometric mean of 0.3 and a geometric standard deviation of 3.9. PMID:17884260

Handl, J; Sachse, R; Jakob, D; Michel, R; Evangelista, H; Gonçalves, A C; de Freitas, A C

2008-02-01

57

Ultrastructural Study on Ultra-Low Frequency Electromagnetic Fields and Transfer Factor Effects on Skin Ulcers  

NASA Astrophysics Data System (ADS)

We determined the effect of 120Hz ultra low frequency electromagnetic field (ELF) on the healing process of skin in 20 Wistar rats distributed in four groups in which chronic dermal ulcers had been produced. The first two groups received a dose of the transfer factor and interferon-beta (IFN-?) every 24 h during 12 days. The third group (positive control) received only electromagnetic field (ELF) sessions, and in the fourth group (negative control), no treatment was applied. The electromagnetic field was applied through a Helmholtz coils; 30 Gauss of intensity. Results shown histological changes that improve the healing process in animals subjected to ELF together with the transfer factor.

Cadena, M. S. Reyes; Chapul, L. Sánchez; Pérez, Javiér; García, M. N. Jiménez; López, M. A. Jiménez; Espíndola, M. E. Sánchez; Perez, R. Paniagua; Hernández, N. A.; Paniagua, G.; Uribe, F.; Nava, J. J. Godina; Segura, M. A. Rodríguez

2008-08-01

58

Energy transfer between a nanosystem and its host fluid: A multiscale factorization approach  

NASA Astrophysics Data System (ADS)

Energy transfer between a macromolecule or supramolecular assembly and a host medium is considered from the perspective of Newton's equations and Lie-Trotter factorization. The development starts by demonstrating that the energy of the molecule evolves slowly relative to the time scale of atomic collisions-vibrations. The energy is envisioned to be a coarse-grained variable that coevolves with the rapidly fluctuating atomistic degrees of freedom. Lie-Trotter factorization is shown to be a natural framework for expressing this coevolution. A mathematical formalism and workflow for efficient multiscale simulation of energy transfer is presented. Lactoferrin and human papilloma virus capsid-like structure are used for validation.

Sereda, Yuriy V.; Espinosa-Duran, John M.; Ortoleva, Peter J.

2014-02-01

59

Energy transfer between a nanosystem and its host fluid: A multiscale factorization approach  

SciTech Connect

Energy transfer between a macromolecule or supramolecular assembly and a host medium is considered from the perspective of Newton's equations and Lie-Trotter factorization. The development starts by demonstrating that the energy of the molecule evolves slowly relative to the time scale of atomic collisions-vibrations. The energy is envisioned to be a coarse-grained variable that coevolves with the rapidly fluctuating atomistic degrees of freedom. Lie-Trotter factorization is shown to be a natural framework for expressing this coevolution. A mathematical formalism and workflow for efficient multiscale simulation of energy transfer is presented. Lactoferrin and human papilloma virus capsid-like structure are used for validation.

Sereda, Yuriy V.; Espinosa-Duran, John M.; Ortoleva, Peter J., E-mail: ortoleva@indiana.edu [Center for Cell and Virus Theory, Department of Chemistry, Indiana University, 800 E. Kirkwood Ave, Bloomington, Indiana 47405 (United States)

2014-02-21

60

Computing the energetic component of the charge-transfer symmetry factor  

E-print Network

-transfer symmetry factor (UI: 0.47; MT: 0.49). The latter is larger than its energetic (TPS: 0.39; UI: 0.23; MT: 0.38) and entropic (UI: 0.25; MT: 0.13) components, given by the variation of the activation energy and entropy with the reaction free energy. The charge...

Drechsel-Grau, Christof

61

DEVELOPMENT OF AN AIR-TO-LEAF VAPOR PHASE TRANSFER FACTOR FOR DIOXINS AND FURANS  

EPA Science Inventory

Results of an experiment in which grass was grown in a greenhouse and outdoors, and in soils of different concentration levels of dioxins and furans, were used in a modeling exercise to derive an air-to-leaf vapor phase transfer factor. The purpose of the experiment was to under...

62

What's in a Word? Extending Learning Factors Analysis to Model Reading Transfer  

Microsoft Academic Search

Learning Factors Analysis (LFA) has been proposed as a generic solution to evaluate and compare cognitive models of learning (1). By performing a heuristic search over a space of statistical models, the researcher may evaluate different cognitive representations of a set of skills. We introduce a scalable application of this framework in the context of transfer in reading and demonstrate

James M. LESZCZENSKI; Joseph E. BECK

63

Factors Contributing to the Upward Transfer of Baccalaureate Aspirants Beginning at Community Colleges  

ERIC Educational Resources Information Center

This study examined factors associated with the upward transfer of baccalaureate aspirants beginning at community colleges. Based on data from the National Education Longitudinal Study of 1988 and the Postsecondary Education Transcript Study, a sequential logistic regression analysis was conducted to predict bachelor's degree-seeking community…

Wang, Xueli

2012-01-01

64

Factors Associated with Transfer of Training in Workplace E-Learning  

ERIC Educational Resources Information Center

Purpose--The purpose of this study is to investigate the effect of factors associated with e-learning, particularly computer attitudes and usability, on transfer of training in workplace e-learning courses. Design/methodology/approach--This study relied on quantitative data obtained from four online survey questionnaires. The sample of this study…

Park, Ji-Hye; Wentling, Tim

2007-01-01

65

Scale-model charge-transfer technique for measuring enhancement factors  

NASA Technical Reports Server (NTRS)

Determination of aircraft electric field enhancement factors is crucial when using airborne field mill (ABFM) systems to accurately measure electric fields aloft. SRI used the scale model charge transfer technique to determine enhancement factors of several canonical shapes and a scale model Learjet 36A. The measured values for the canonical shapes agreed with known analytic solutions within about 6 percent. The laboratory determined enhancement factors for the aircraft were compared with those derived from in-flight data gathered by a Learjet 36A outfitted with eight field mills. The values agreed to within experimental error (approx. 15 percent).

Kositsky, J.; Nanevicz, J. E.

1991-01-01

66

In vivo transfer of an R factor within the lower gastro-intestinal tract of sheep.  

PubMed Central

The transfer of an R factor from donor E. coli introduced into the rumen of adult sheep to strains of the coliform microflora resident post rumen in the lower gastro-intestinal tract was found to be greatly increased when the animals were subjected to a short period of starvation (ca. 24-48 h). This also resulted in coliform organisms containing the resistance determinants of the R factor being excreted for much longer periods, sometimes for months afterwards. As no antibiotic treatment was given to the animals during these experiments, possession of the R factor should have conferred no selective advantages on the host cells and other plasmids could possibly be transferred similarly in vivo in sheep or other ruminants and perhaps also within the gut of monogastric animals. PMID:333023

Smith, M. G.

1977-01-01

67

Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio to High Momentum Transfer  

SciTech Connect

The electromagnetic form factors of the nucleon characterize the effect of its internal structure on its response to an electromagnetic probe as studied in elastic electronnucleon scattering. These form factors are functions of the squared four-momentum transfer Q2 between the electron and the proton. The two main classes of observables of this reaction are the scattering cross section and polarization asymmetries, both of which are sensitive to the form factors in different ways. When considering large f momentum transfers, double-polarization observables offer superior sensitivity to the electric form factor. This thesis reports the results of a new measurement of the ratio of the electric and magnetic form factors of the proton at high momentum transfer using the recoil polarization technique. A polarized electron beam was scattered from a liquid hydrogen target, transferring polarization to the recoiling protons. These protons were detected in a magnetic spectrometer which was used to reconstruct their kinematics, including their scattering angles and momenta, and the position of the interaction vertex. A proton polarimeter measured the polarization of the recoiling protons by measuring the azimuthal asymmetry in the angular distribution of protons scattered in CH2 analyzers. The scattered electron was detected in a large acceptance electromagnetic calorimeter in order to suppress inelastic backgrounds. The measured ratio of the transverse and longitudinal polarization components of the scattered proton is directly proportional to the ratio of form factors GpE=GpM. The measurements reported in this thesis took place at Q2 =5.2, 6.7, and 8.5 GeV2, and represent the most accurate measurements of GpE in this Q2 region to date.

Andrew Puckett

2010-02-01

68

Improved retroviral episome transfer of transcription factors enables sustained cell fate modification.  

PubMed

Retroviral vectors are versatile gene transfer vehicles widely used in basic research and gene therapy. Mutation of retroviral integrase converts these vectors into transient, integration-deficient gene delivery vehicles associated with a high degree of biosafety. We explored the option to use integration-deficient retroviral vectors to achieve transient ectopic expression of transcription factors, which is considered an important tool for induced cell fate conversion. Stepwise optimization of the retroviral episome transfer as exemplified for the transcription factor Oct4 enabled to improve both expression magnitude and endurance. Long terminal repeat-driven ?-retroviral vectors were identified as the most suitable vector architecture. Episomal expression was enhanced by epigenetic modifiers, and Oct4 activity was increased following fusion to a minimal transactivation motif of herpes simplex virus VP16. Based on kinetic analyses, we identified optimal time intervals for repeated vector administration and established prolonged expression windows of choice. Providing proof-of-concept, episomal transfer of Oct4 was potent to mediate conversion of human fibroblasts stably expressing Klf4, Sox2 and c-Myc into induced pluripotent stem cells, which were mainly free of residual Oct4 vector integration. This study provides evidence for suitability of retroviral episome transfer of transcription factors for cell fate conversion, allowing the generation of distinct patient- or disease-specific cell types. PMID:25102011

Schott, J W; Hoffmann, D; Maetzig, T; Müller, F-J; Steinemann, D; Zychlinski, D; Cantz, T; Baum, C; Schambach, A

2014-11-01

69

The ultrasonic-enhanced factor of mass-transfer coefficient in the supercritical carbon dioxide extraction  

NASA Astrophysics Data System (ADS)

Based on several hypotheses about the process of supercritical carbon dioxide extraction, the onflow around the solute granule is figured out by the Navier-Stocks equation. In combination with the Higbie’s solute infiltration model, the link between the mass-transfer coefficient and the velocity of flow is found. The mass-transfer coefficient with the ultrasonical effect is compared with that without the ultrasonical effect, and then a new parameter named the ultrasonic-enhanced factor of mass-transfer coefficient is brought forward, which describes the mathematical model of the supercritical carbon dioxide extraction process enhanced by ultrasonic. The model gives out the relationships among the ultrasonical power, the ultrasonical frequency, the radius of solute granule and the ultrasonic-enhanced factor of mass-transfer coefficient. The results calculated by this model fit well with the experimental data, including the extraction of Coix Lacryma-jobi Seed Oil (CLSO) and Coix Lacryma-jobi Seed Ester (CLSE) from coix seeds and the extraction of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) from the alga by means of the ultrasonic-enhanced supercritical carbon dioxide extraction (USFE) and the supercritical carbon dioxide extraction (SFE) respectively. This proves the rationality of the ultrasonic-enhanced factor model. The model provides a theoretical basis for the application of ultrasonic-enhanced supercritical fluid extraction technique.

Luo, Benyi; Lu, Yigang

2008-10-01

70

Bactericidal factor produced by Haemophilus influenzae b: partial purification of the factor and transfer of its genetic determinant.  

PubMed

When aerobically grown on complex media, Haemophilus influenzae b and unencapsulated variants, Rb strains, produced a bactericidal factor that was active against other Haemophilus species and certain genera of the Enterobacteriaceae. A total of 341 clinical isolates of Haemophilus were tested for susceptibility to the factor. Ninety-three percent of H. influenzae (nontypable), 75% of H. haemolyticus, 71% of H. parainfluenzae, and 22% of H. parahaemolyticus were susceptible. H. influenaze b strains were resistant producers of the bactericidal factor and H. influenzae f strains were susceptible nonproducers. Only one strain each of H. aegyptius and H. aphrophilus was isolated and each was susceptible and resistant, respectively. 143 clinical isolates of the Enterobacteriaceae were tested and of those 82% of Escherichia coli, 85% of Salmonella sp., and all Citrobacter sp., Shigella sp., and Yersinia sp. were sensitive to the bactericidal factor produced by H. influenzae b. Attempts to isolate the bactericidal activity from mechanically disrupted, solubilized, or osmotically shocked cells failed to release active bactericidal factor. However, we partially purified the bactericidal factor from the spent culture medium of aerobically grown H. influenzae b by a series of extractions. The ability to produce the bactericidal factor was transferable to nonproducer strains without also genetically transforming for type b encapsulation. The converse was also true in that type b capsules were produced by transformed H. influenzae Rd strains but no bactericidal factor was detected from these strains. Additionally, nitrosoguanidine-induced mutants of H. influenzae b lost the ability to produce bactericidal factor without loss of their type-specific capsule, demonstrating that production of the bactericidal factor was genetically separable from production of the type capsule of H. influenzae b. PMID:301008

Venezia, R A; Matusiak, P M; Robertson, R G

1977-04-01

71

Survey of literature on convective heat transfer coefficients and recovery factors for high atmosphere thermometry  

NASA Technical Reports Server (NTRS)

Heat transfer phenomena of rarefied gas flows is discussed based on a literature survey of analytical and experimental rarefied gas dynamics. Subsonic flows are emphasized for the purposes of meteorological thermometry in the high atmosphere. The heat transfer coefficients for three basic geometries are given in the regimes of free molecular flow, transition flow, slip flow, and continuum flow. Different types of heat phenomena, and the analysis of theoretical and experimental data are presented. The uncertainties calculated from the interpolation rule compared with the available experimental data are discussed. The recovery factor for each geometry in subsonic rarefied flows is also given.

Chung, S.

1973-01-01

72

[Team-based community psychiatry: importance of context factors and transferability of evidence from studies].  

PubMed

The German Society for Psychiatry, Psychotherapy and Neurology (DGPPN) guidelines on psychosocial interventions for people with severe mental illness appraise the transferability of results of trials evaluating community-based mental health services to the German situation. This assessment has to draw on research results on factors determining effectiveness. This must be seen against the background of a lack of high-quality trials in Germany. The article discusses system, context and setting factors related to the transfer of evidence on community-based service models from other countries. These issues are discussed on the basis of evidence concerning the models of case management, assertive community treatment and community mental health teams. International differences in study findings are highlighted and the importance of treatment-as-usual in influencing study results is emphasized. The more control services including elements of community-based care there are and the less the pressure to reduce inpatient treatment (threshold to inpatient care admission), the smaller the relative effect sizes of innovative care models will be.In the absence of direct evidence, careful examination of transferability is required before introducing health care models. Research has revealed solid evidence for several factors influencing the effects of innovative community mental health care. Among key factors in the care of people with severe mental illness, home visits and joint team responsibility for both psychiatric and social care were identified. This evidence can facilitate the adaptation of successful mental health care models in Germany. PMID:22688090

Weinmann, S; Gühne, U; Kösters, M; Gaebel, W; Becker, T

2012-07-01

73

?-Lactam Antibiotics Induce the SOS Response and Horizontal Transfer of Virulence Factors in Staphylococcus aureus  

PubMed Central

Antibiotics that interfere with DNA replication and cell viability activate the SOS response. In Staphylococcus aureus, the antibiotic-induced SOS response promotes replication and high-frequency horizontal transfer of pathogenicity island-encoded virulence factors. Here we report that ?-lactams induce a bona fide SOS response in S. aureus, characterized by the activation of the RecA and LexA proteins, the two master regulators of the SOS response. Moreover, we show that ?-lactams are capable of triggering staphylococcal prophage induction in S. aureus lysogens. Consequently, and as previously described for SOS induction by commonly used fluoroquinolone antibiotics, ?-lactam-mediated phage induction also resulted in replication and high-frequency transfer of the staphylococcal pathogenicity islands, showing that such antibiotics may have the unintended consequence of promoting the spread of bacterial virulence factors. PMID:16547063

Maiques, Elisa; Úbeda, Carles; Campoy, Susana; Salvador, Noelia; Lasa, Íñigo; Novick, Richard P.; Barbé, Jordi; Penadés, José R.

2006-01-01

74

Evaluation of clinical factors influencing pregnancy rate in frozen embryo transfer  

PubMed Central

Background: Frozen embryo transfer (FET) is one of the most important supplementary procedures in the treatment of infertile couples. While general information concerning the outcome of fresh embryo transfer has been documented, paucity of investigations has addressed the clinical factors influenced on pregnancy rates in FET. Objective: In this study, we performed a retrospective analysis of clinical factors that potentially influence the outcome of FET. Materials and Methods: We reviewed the data from 372 women who were subjected to FET registered from April 2009-2011 at the Research and clinical center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Baseline data and pregnancy rate were collected. The data were analyzed statistically using the Kolmogorov-Smirnov, and Mann-Whitney tests. Results: The clinical pregnancy rate was 57.7 and 29.2% in women <35 years old, and women >35 years old, respectively (p<0.0001). Clinical pregnancy rates in women with FSH <10 IU/ml, and FSH >10 IU/ml were 56.3% and 17.5 %, respectively (p<0.0001). Whereas the other clinical parameters consist of reason of fetus freezing, primary IVF protocol, IVF procedure, endometrial thickness, treatment duration to fetal transfer found to be unrelated to FET outcomes (p>0.05). Conclusion: Female age and basal FSH level are the most important factors influencing the clinical pregnancy rate following FET. PMID:25114675

Eftekhar, Maryam; Rahmani, Elham; Pourmasumi, Soheila

2014-01-01

75

The orientational freedom of molecular probes. The orientation factor in intramolecular energy transfer.  

PubMed Central

The measurement of the efficiency of Förster long-range resonance energy transfer between donor (D) and acceptor (A) luminophores attached to the same macromolecular substrate can be used to estimate the D-A separation, R. If the D and A transition dipoles sample all orientations with respect to the substrate (the isotropic condition) in a time short compared with the transfer time (the dynamic averaging condition), the average orientation factor less than K2 greater than is 2/3. If the isotropic condition is not satisfied but the dynamic averaging condition is, upper and lower bounds for less than K2 greater than, and thus R, may be obtained from observed D and A depolarizations, and these limits may be further narrowed if the transfer depolarization is also known. This paper offers experimental protocols for obtaining this reorientational information and presents contour plots of less than K2 greater than min and less than K2 greater than max as functions of generally observable depolarizations. This permits an uncertainty to be assigned to the determined value of R. The details of the D and A reoreintational process need not be known, but the orientational distributions are assumed to have at least approximate axial symmetry with respect to a stationary substrate. Average depolarization factors are derived for various orientational distribution functions that demonstrate the effects of various mechanisms for reorientation of the luminophores. It is shown that in general the static averaging regime does not lend itself to determinations of R. PMID:262414

Dale, R E; Eisinger, J; Blumberg, W E

1979-01-01

76

100% Classification Accuracy Considered Harmful: The Normalized Information Transfer Factor Explains the Accuracy Paradox  

PubMed Central

The most widely spread measure of performance, accuracy, suffers from a paradox: predictive models with a given level of accuracy may have greater predictive power than models with higher accuracy. Despite optimizing classification error rate, high accuracy models may fail to capture crucial information transfer in the classification task. We present evidence of this behavior by means of a combinatorial analysis where every possible contingency matrix of 2, 3 and 4 classes classifiers are depicted on the entropy triangle, a more reliable information-theoretic tool for classification assessment. Motivated by this, we develop from first principles a measure of classification performance that takes into consideration the information learned by classifiers. We are then able to obtain the entropy-modulated accuracy (EMA), a pessimistic estimate of the expected accuracy with the influence of the input distribution factored out, and the normalized information transfer factor (NIT), a measure of how efficient is the transmission of information from the input to the output set of classes. The EMA is a more natural measure of classification performance than accuracy when the heuristic to maximize is the transfer of information through the classifier instead of classification error count. The NIT factor measures the effectiveness of the learning process in classifiers and also makes it harder for them to “cheat” using techniques like specialization, while also promoting the interpretability of results. Their use is demonstrated in a mind reading task competition that aims at decoding the identity of a video stimulus based on magnetoencephalography recordings. We show how the EMA and the NIT factor reject rankings based in accuracy, choosing more meaningful and interpretable classifiers. PMID:24427282

Valverde-Albacete, Francisco J.; Peláez-Moreno, Carmen

2014-01-01

77

Transfer of Cadmium from Soil to Vegetable in the Pearl River Delta area, South China  

PubMed Central

The purpose of this study was to investigate the regional Cadmium (Cd) concentration levels in soils and in leaf vegetables across the Pearl River Delta (PRD) area; and reveal the transfer characteristics of Cadmium (Cd) from soils to leaf vegetable species on a regional scale. 170 paired vegetables and corresponding surface soil samples in the study area were collected for calculating the transfer factors of Cadmium (Cd) from soils to vegetables. This investigation revealed that in the study area Cd concentration in soils was lower (mean value 0.158 mg kg?1) compared with other countries or regions. The Cd-contaminated areas are mainly located in west areas of the Pearl River Delta. Cd concentrations in all vegetables were lower than the national standard of Safe vegetables (0.2 mg kg?1). 88% of vegetable samples met the standard of No-Polluted vegetables (0.05 mg kg?1). The Cd concentration in vegetables was mainly influenced by the interactions of total Cd concentration in soils, soil pH and vegetable species. The fit lines of soil-to-plant transfer factors and total Cd concentration in soils for various vegetable species were best described by the exponential equation (), and these fit lines can be divided into two parts, including the sharply decrease part with a large error range, and the slowly decrease part with a low error range, according to the gradual increasing of total Cd concentrations in soils. PMID:25247431

Zhang, Huihua; Chen, Junjian; Zhu, Li; Yang, Guoyi; Li, Dingqiang

2014-01-01

78

Strategic factors in the development of the National Technology Transfer Network  

NASA Technical Reports Server (NTRS)

Broad consensus among industry and government leaders has developed over the last decade on the importance of applying the U.S. leadership in research and development (R&D) to strengthen competitiveness in the global marketplace, and thus enhance national prosperity. This consensus has emerged against the backdrop of increasing economic competition, and the dramatic reduction of military threats to national security with the end of the Cold War. This paper reviews the key factors and considerations that shaped - and continue to influence - the development of the Regional Technoloty Transfer Centers (RTTC) and the National Technology Transfer Center (NTTC). Also, the future role of the national network in support of emerging technology policy initiatives will be explored.

Root, Jonathan F.; Stone, Barbara A.

1993-01-01

79

Inhibition of target cell mitochondrial electron transfer by tumor necrosis factor.  

PubMed

Using digitonin permeabilization to assay mitochondrial electron transfer, we have found that respiratory activity (succinoxidase and cytochrome oxidase) in three mouse fibroblast lines is completely eliminated by incubation with human recombinant tumor necrosis factor-alpha (hrTNF). As with cytotoxicity, hrTNF-induced mitochondrial dysfunction occurs in resistant cells upon inhibition of protein synthesis, whereas sensitive cells exhibit spontaneous respiratory inhibition. In C3HA cells, inhibition is detectable 1.5-2 h after hrTNF addition, preceding cell lysis by at least 5 h (as measured by dye exclusion), and is approximately coincidental with morphological changes we have previously reported for this cell line. LM cells also exhibit inhibition of electron transfer, coincidental with morphological changes. These results suggest that bioenergetic dysfunction may be involved in the cytotoxic mechanism of TNF. PMID:2721674

Lancaster, J R; Laster, S M; Gooding, L R

1989-05-01

80

Relativistic radiative transfer in relativistic plane-parallel flows: Behavior of the Eddington factor  

NASA Astrophysics Data System (ADS)

Relativistic radiative transfer in a relativistic plane-parallel flow which is accelerated from its base, like an accretion disk wind, is numerically examined under a fully special-relativistic treatment. We first derive relativistic formal solutions. We then iteratively solve the relativistic transfer equation for several cases such as radiative equilibrium or local thermodynamic equilibrium, and obtain specific intensities in the inertial and comoving frames, as well as moment quantities and the Eddington factor. Moment quantities are rather different in each case, but the behavior of the Eddington factor for the plane-parallel case is quite similar in all cases. The Eddington factor generally depends on the flow velocity v as well as the optical depth ?. In the case of relativistic plane-parallel flows, in an optically thin regime of ? ? 1, it is slightly larger than 1/3 at very slow speed, it becomes smaller than 1/3 at mildly relativistic speed, and it again increases up to unity in the highly relativistic case. At highly relativistic speed, on the other hand, it becomes larger than 1/3 even in an optically thick regime. We find the Eddington approximation is fairly good, except for ? ? 1 or v/c ? 0.9, although the moment formalism under the Eddington approximation has some defects at v/c=1/?{3}.

Fukue, Jun

2014-07-01

81

Intermedia transfer factors for fifteen toxic pollutants released to air basins in California  

SciTech Connect

This report provides a summary definition of the intermedia-transfer factors (ITFs). Methods are discussed for estimating these parameters in the absence of measured values, and the estimation errors inherent in these estimation methods are considered. A detailed summary is provided of measured and estimated ITF values for fifteen air contaminants. They include: 1,3 butadiene; cadmium; cellosolve; cellosolve acetate; chloroform; di-2-ethylhexylphthalate; 1,4-dioxame; hexachlorobenzene; inorganic arsenic; inorganic lead; nickel; tetrachloroethylene; toluene; toluene-2,4-diisocyanate; and 1,3-xylene. Recommendations are made regarding the expected value and variance in these values for use in exposure models.

McKone, T.E.; Daniels, J.I. [Lawrence Livermore National Lab., CA (United States); Chiao, F.F.; Hsieh, D.P.H. [Univ. of California, Davis, CA (United States)

1993-10-01

82

In vitro studies during long term oral administration of specific transfer factor  

Microsoft Academic Search

153 patients suffering from recurrent pathologies, i.e. viral infections (keratitis, keratouveitis, genital and labial herpes)\\u000a uveitis, cystitis, and candidiasis were treated with in vitro produced transfer factor (TF) specific for HSV-1\\/2, CMV and\\u000a Candida albicans. The cell-mediated immunity of seropositive patients to HSV-1\\/2 and\\/or CMV viruses was assessed using the\\u000a leucocyte migration inhibition test (LMT) and lymphocyte stimulation test (LST)

Giancarlo Pizza; Caterina De Vinci; Vittorio Fornarola; Aldopaolo Palareti; Olavio Baricordi; Dimitri Viza

1996-01-01

83

New heat transfer and friction factor design data for perforated plate heat exchangers  

NASA Astrophysics Data System (ADS)

Perforated plate heat exchangers have been found to have inherently low axial conduction and are therefore excellent candidates for cryogenic applications where an all-metal design is required. A total of three plate cores were tested; two were chemically etched and the other mechanically punched. Hole size, percent open area and plate thickness parameters were varied among the plates. Experimental results were compared to analytical projections and found to differ significantly. The single-blow, transient test technique was used to determine the heat transfer coefficients and the isothermal pressure drop test was used to determine friction factors, as a function of Reynolds number.

Hubbell, Richard H.; Cain, Christina L.

84

Aggregated Transfer Factors For Small Mammals Collected From the Exposed Sediments Of A 137 Cs Contaminated Reservoir  

SciTech Connect

{sup 137}Cs transfer factors were computed for small mammals collected from the dried sediment areas of a partially drained, contaminated reservoir. Soil {sup 137}Cs concentrations were heterogeneous on small and large spatial scales, with a geometric mean of 253.1 Bq/kg dry weight. About 50% of the variance in cotton rat Sigmodon hispidus tissue {sup 137}Cs levels was explained by variation in soil {sup 137}Cs levels. Soil to animal transfer factors (whole body dry weight) averaged 6.0 for cotton rats and 1.2 for cotton mice Peromyscus gossypinus. These values are similar to {sup 137}Cs transfer factors for herbivorous, homeothermic animals from other contaminated ecosystems. Site-specific transfer factors can significantly affect the estimation of dose. In the RESRAD-BIOTA dose model, the default transfer factor for {sup 137}Cs in terrestrial animals is 110 resulting in an estimate of radiation dose to terrestrial biota that is 16 times more than the dose calculated with the actual measured transfer factor.

Paller, Michael H.; Jannika, G. Timothy; Wike, Lynn D

2005-10-04

85

Neutron spectroscopic factors of $^{55}$Ni hole-states from (p,d) transfer reactions  

E-print Network

Spectroscopic information has been extracted on the hole-states of $^{55}$Ni, the least known of the quartet of nuclei ($^{55}$Ni, $^{57}$Ni, $^{55}$Co and $^{57}$Co), one neutron away from $^{56}$Ni, the N=Z=28 double magic nucleus. Using the $^{1}$H($^{56}$Ni,d)$^{55}$Ni transfer reaction in inverse kinematics, neutron spectroscopic factors, spins and parities have been extracted for the f$_{7/2}$, p$_{3/2}$ and the s$_{1/2}$ hole-states of $^{55}$Ni. This new data provides a benchmark for large basis calculations that include nucleonic orbits in both the sd and pf shells. State of the art calculations have been performed to describe the excitation energies and spectroscopic factors of the s$_{1/2}$ hole-state below Fermi energy.

A. Sanetullaev; M. B. Tsang; W. G. Lynch; Jenny Lee; D. Bazin; K. P. Chan; D. Coupland; V. Henzl; D. Henzlova; M. Kilburn; A. M. Rogers; Z. Y. Sun; M. Youngs; R. J. Charity; L. G. Sobotka; M. Famiano; S. Hudan; D. Shapira; W. A. Peters; C. Barbieri; M. Hjorth-Jensen; M. Horoi; T. Otsuka; T. Suzuki; Y. Utsuno

2014-01-30

86

Statistical iterative reconstruction using fast optimization transfer algorithm with successively increasing factor in Digital Breast Tomosynthesis  

NASA Astrophysics Data System (ADS)

Statistical iterative reconstruction exhibits particularly promising since it provides the flexibility of accurate physical noise modeling and geometric system description in transmission tomography system. However, to solve the objective function is computationally intensive compared to analytical reconstruction methods due to multiple iterations needed for convergence and each iteration involving forward/back-projections by using a complex geometric system model. Optimization transfer (OT) is a general algorithm converting a high dimensional optimization to a parallel 1-D update. OT-based algorithm provides a monotonic convergence and a parallel computing framework but slower convergence rate especially around the global optimal. Based on an indirect estimation on the spectrum of the OT convergence rate matrix, we proposed a successively increasing factor- scaled optimization transfer (OT) algorithm to seek an optimal step size for a faster rate. Compared to a representative OT based method such as separable parabolic surrogate with pre-computed curvature (PC-SPS), our algorithm provides comparable image quality (IQ) with fewer iterations. Each iteration retains a similar computational cost to PC-SPS. The initial experiment with a simulated Digital Breast Tomosynthesis (DBT) system shows that a total 40% computing time is saved by the proposed algorithm. In general, the successively increasing factor-scaled OT exhibits a tremendous potential to be a iterative method with a parallel computation, a monotonic and global convergence with fast rate.

Xu, Shiyu; Zhang, Zhenxi; Chen, Ying

2014-03-01

87

Friction factor and heat transfer of nanofluids containing cylindrical nanoparticles in laminar pipe flow  

NASA Astrophysics Data System (ADS)

Numerical simulations of polyalphaolefins-Al2O3 nanofluids containing cylindrical nanoparticles in a laminar pipe flow are performed by solving the Navier-Stokes equation with term of cylindrical nanoparticles, the general dynamic equation for cylindrical nanoparticles, and equation for nanoparticle orientation. The distributions of particle number and volume concentration, the friction factor, and heat transfer are obtained and analyzed. The results show that distributions of nanoparticle number and volume concentration are non-uniform across the section, with larger and smaller values in the region near the pipe center and near the wall, respectively. The non-uniformity becomes significant with the increase in the axial distance from the inlet. The friction factor decreases with increasing Reynolds number. The relationships between the friction factor and the nanoparticle volume concentration as well as particle aspect ratio are dependent on the Reynolds number. The Nusselt number of nanofluids, directly proportional to the Reynolds number, particle volume concentration, and particle aspect ratio, is higher near the pipe entrance than at the downstream locations. The rate of increase in Nusselt number at lower particle volume concentration is more than that at higher concentration. Finally, the expressions of friction factor and Nusselt number as a function of particle volume concentration, particle aspect ratio, and Reynolds number are derived based on the numerical data.

Lin, Jianzhong; Xia, Yi; Ku, Xiaoke

2014-10-01

88

Heat-transfer and friction factor design data for all-metal compact heat exchangers  

NASA Astrophysics Data System (ADS)

To improve system life, an effort was undertaken to develop all-metal compact heat exchangers to replace existing heat exchangers which contain organic materials. Eliminating organic materials increases system life because outgassing organics can contaminate the helium working fluid and reduce system life. Perforated plate heat exchangers were found to have inherently low axial conduction and are therefore excellent candidates for cryogenic applications where an all-metal design is required. A total of 11 plate cores were tested; 2 were chemically etched, 1 was mechanically punched, and 8 were manufactured using electron beam drilling. Hole size, percent open area, and plate thickness parameters were varied among the plates. Experimental results were compared to analytical projections and found to differ significantly. The single-blow transient test technique was used to determine the heat transfer coefficients and the isothermal pressure drop test was used to determine friction factors, as a function of Reynolds number.

Cain, Christina L.

1989-03-01

89

Modification of an impulse-factoring orbital transfer technique to account for orbit determination and maneuver execution errors  

NASA Technical Reports Server (NTRS)

A method has previously been developed to satisfy terminal rendezvous and intermediate timing constraints for planetary missions involving orbital operations. The method uses impulse factoring in which a two-impulse transfer is divided into three or four impulses which add one or two intermediate orbits. The periods of the intermediate orbits and the number of revolutions in each orbit are varied to satisfy timing constraints. Techniques are developed to retarget the orbital transfer in the presence of orbit-determination and maneuver-execution errors. Sample results indicate that the nominal transfer can be retargeted with little change in either the magnitude (Delta V) or location of the individual impulses. Additonally, the total Delta V required for the retargeted transfer is little different from that required for the nominal transfer. A digital computer program developed to implement the techniques is described.

Kibler, J. F.; Green, R. N.; Young, G. R.; Kelly, M. G.

1974-01-01

90

Experimental heat transfer and friction factors in turbulated cooling passages of different aspect ratios, where turbulators are staggered  

NASA Astrophysics Data System (ADS)

Turbulator ribs of different height/passage hydraulic diameter, positioned in different configurations relative to one another, are used in advanced aircraft engines to enhance heat transfer from the blade surface to the internal cooling air. An experimental investigation has been conducted to ascertain the effect that turbulators positioned perpendicular to the direction of flow and in a staggered configuration have on heat transfer coefficients and friction factors in cooling passages of different aspect ratios. Comparisons are made between staggered and in-line turbulator configuration results; higher heat transfer coefficients are obtained for the staggered configuration.

Taslim, M. E.; Spring, S. D.

1988-07-01

91

Direct transfer of transforming growth factor beta 1 gene into arteries stimulates fibrocellular hyperplasia.  

PubMed

The arterial wall responds to thrombosis or mechanical injury through the induction of specific gene products that increase cellular proliferation and connective tissue formation. These changes result in intimal hyperplasia that is observed in restenosis and the early phases of atherosclerosis. Transforming growth factor beta 1 (TGF-beta 1) is a secreted multi-functional protein that plays an important role in embryonal development and in repair following tissue injury. However, the function of TGF-beta 1 in vascular cell growth in vivo has not been defined. In this report, we have evaluated the role of TGF-beta 1 in the pathophysiology of intimal and medial hyperplasia by gene transfer of an expression plasmid encoding active TGF-beta 1 into porcine arteries. Expression of TGF-beta 1 in normal arteries resulted in substantial extracellular matrix production accompanied by intimal and medial hyperplasia. Increased procollagen, collagen, and proteoglycan synthesis in the neointima was demonstrated by immunohistochemistry relative to control transfected arteries. Expression of TGF-beta 1 induced a distinctly different program of gene expression and biologic response from the platelet-derived growth factor B (PDGF B) gene: procollagen synthesis induced by TGF-beta 1 was greater, and cellular proliferation was less prominent. These findings show that TGF-beta 1 differentially modulates extracellular matrix production and cellular proliferation in the arterial wall in vivo and could play a reparative role in the response to arterial injury. PMID:8248168

Nabel, E G; Shum, L; Pompili, V J; Yang, Z Y; San, H; Shu, H B; Liptay, S; Gold, L; Gordon, D; Derynck, R

1993-11-15

92

Direct transfer of transforming growth factor beta 1 gene into arteries stimulates fibrocellular hyperplasia.  

PubMed Central

The arterial wall responds to thrombosis or mechanical injury through the induction of specific gene products that increase cellular proliferation and connective tissue formation. These changes result in intimal hyperplasia that is observed in restenosis and the early phases of atherosclerosis. Transforming growth factor beta 1 (TGF-beta 1) is a secreted multi-functional protein that plays an important role in embryonal development and in repair following tissue injury. However, the function of TGF-beta 1 in vascular cell growth in vivo has not been defined. In this report, we have evaluated the role of TGF-beta 1 in the pathophysiology of intimal and medial hyperplasia by gene transfer of an expression plasmid encoding active TGF-beta 1 into porcine arteries. Expression of TGF-beta 1 in normal arteries resulted in substantial extracellular matrix production accompanied by intimal and medial hyperplasia. Increased procollagen, collagen, and proteoglycan synthesis in the neointima was demonstrated by immunohistochemistry relative to control transfected arteries. Expression of TGF-beta 1 induced a distinctly different program of gene expression and biologic response from the platelet-derived growth factor B (PDGF B) gene: procollagen synthesis induced by TGF-beta 1 was greater, and cellular proliferation was less prominent. These findings show that TGF-beta 1 differentially modulates extracellular matrix production and cellular proliferation in the arterial wall in vivo and could play a reparative role in the response to arterial injury. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8248168

Nabel, E G; Shum, L; Pompili, V J; Yang, Z Y; San, H; Shu, H B; Liptay, S; Gold, L; Gordon, D; Derynck, R

1993-01-01

93

Are spectroscopic factors from transfer reactions consistent with asymptotic normalisation coefficients?  

E-print Network

It is extremely important to devise a reliable method to extract spectroscopic factors from transfer cross sections. We analyse the standard DWBA procedure and combine it with the asymptotic normalisation coefficient, extracted from an independent data set. We find that the single particle parameters used in the past generate inconsistent asymptotic normalization coefficients. In order to obtain a consistent spectroscopic factor, non-standard parameters for the single particle overlap functions can be used but, as a consequence, often reduced spectroscopic strengths emerge. Different choices of optical potentials and higher order effects in the reaction model are also studied. Our test cases consist of: $^{14}$C(d,p)$^{15}$C(g.s.) at $E_d^{lab}=14$ MeV, $^{16}$O(d,p)$^{17}$O(g.s.) at $E_d^{lab}=15$ MeV and $^{40}$Ca(d,p)$^{41}$Ca(g.s.) at $E_d^{lab}=11$ MeV. We underline the importance of performing experiments specifically designed to extract ANCs for these systems.

D. Y. Pang; F. M. Nunes; A. M. Mukhamedzhanov

2007-01-24

94

Isolation and Characterization of cLV25, a Bacteroides fragilis Chromosomal Transfer Factor Resembling Multiple Bacteroides sp. Mobilizable Transposons  

PubMed Central

Horizontal DNA transfer contributes significantly to the dissemination of antibiotic resistance genes in Bacteroides fragilis. To further our understanding of DNA transfer in B. fragilis, we isolated and characterized a new transfer factor, cLV25. cLV25 was isolated from B. fragilis LV25 by its capture on the nonmobilizable Escherichia coli-Bacteroides shuttle vector pGAT400?BglII. Similar to other Bacteroides sp. transfer factors, cLV25 was mobilized in E. coli by the conjugative plasmid R751. Using Tn1000 mutagenesis and deletion analysis of cLV25, two mobilization genes, bmgA and bmgB, were identified, whose predicted proteins have similarity to DNA relaxases and mobilization proteins, respectively. In particular, BmgA and BmgB were homologous to MocA and MocB, respectively, the two mobilization proteins of the B. fragilis mobilizable transposon Tn4399. A cis-acting origin of transfer (oriT) was localized to a 353-bp region that included nearly all of the intergenic region between bmgB and orf22 and overlapped with the 3? end of orf22. This oriT contained a putative nic site sequence but showed no significant similarity to the oriT regions of other transfer factors, including Tn4399. Despite the lack of sequence similarity between the oriTs of cLV25 and Tn4399, a mutation in the cLV25 putative DNA relaxase, bmgA, was partially complemented by Tn4399. In addition to the functional cross-reaction with Tn4399, a second distinguishing feature of cLV25 is that predicted proteins have similarity to proteins encoded not only by Tn4399 but by several Bacteroides sp. transfer factors, including NBU1, NBU2, CTnDOT, Tn4555, and Tn5520. PMID:11889096

Bass, Kathleen A.; Hecht, David W.

2002-01-01

95

Isolation and characterization of cLV25, a Bacteroides fragilis chromosomal transfer factor resembling multiple Bacteroides sp. mobilizable transposons.  

PubMed

Horizontal DNA transfer contributes significantly to the dissemination of antibiotic resistance genes in Bacteroides fragilis. To further our understanding of DNA transfer in B. fragilis, we isolated and characterized a new transfer factor, cLV25. cLV25 was isolated from B. fragilis LV25 by its capture on the nonmobilizable Escherichia coli-Bacteroides shuttle vector pGAT400DeltaBglII. Similar to other Bacteroides sp. transfer factors, cLV25 was mobilized in E. coli by the conjugative plasmid R751. Using Tn1000 mutagenesis and deletion analysis of cLV25, two mobilization genes, bmgA and bmgB, were identified, whose predicted proteins have similarity to DNA relaxases and mobilization proteins, respectively. In particular, BmgA and BmgB were homologous to MocA and MocB, respectively, the two mobilization proteins of the B. fragilis mobilizable transposon Tn4399. A cis-acting origin of transfer (oriT) was localized to a 353-bp region that included nearly all of the intergenic region between bmgB and orf22 and overlapped with the 3' end of orf22. This oriT contained a putative nic site sequence but showed no significant similarity to the oriT regions of other transfer factors, including Tn4399. Despite the lack of sequence similarity between the oriTs of cLV25 and Tn4399, a mutation in the cLV25 putative DNA relaxase, bmgA, was partially complemented by Tn4399. In addition to the functional cross-reaction with Tn4399, a second distinguishing feature of cLV25 is that predicted proteins have similarity to proteins encoded not only by Tn4399 but by several Bacteroides sp. transfer factors, including NBU1, NBU2, CTnDOT, Tn4555, and Tn5520. PMID:11889096

Bass, Kathleen A; Hecht, David W

2002-04-01

96

Plasmid Transfer of Plasminogen K1-5 Reduces Subcutaneous Hepatoma Growth by Affecting Inflammatory Factors  

PubMed Central

There is evidence that plasminogen K1-5 (PlgK1-5) directly affects tumour cells and inflammation. Therefore, we analysed if PlgK1-5 has immediate effects on hepatoma cells and inflammatory factors in vitro and in vivo. In vitro, effects of plasmid encoding PlgK1-5 (pK1-5) on Hepa129, Hepa1-6, and HuH7 cell viability, apoptosis, and proliferation as well as VEGF and TNF-alpha expression and STAT3-phosphorylation were investigated. In vivo, tumour growth, proliferation, vessel density, and effects on vascular endothelial growth factor (VEGF) and tumour necrosis factor alpha (TNF-alpha) expression were examined following treatment with pK1-5. In vivo, pK1-5 halved cell viability; cell death was increased by up to 15% compared to the corresponding controls. Proliferation was not affected. VEGF, TNF-alpha, and STAT3-phosphorylation were affected following treatment with pK1-5. In vivo, ten days after treatment initiation, pK1-5 reduced subcutaneous tumour growth by 32% and mitosis by up to 77% compared to the controls. Vessel density was reduced by 50%. TNF-alpha levels in tumour and liver tissue were increased, whereas VEGF levels in tumours and livers were reduced after pK1-5 treatment. Taken together, plasmid gene transfer of PlgK1-5 inhibits hepatoma (cell) growth not only by reducing vessel density but also by inducing apoptosis, inhibiting proliferation, and triggering inflammation. PMID:24895598

Koch, Lea A.; Strassburg, Christian P.; Raskopf, Esther

2014-01-01

97

Factors Influencing Lava-Substrate Heat Transfer and Implications for Thermomechanical Erosion  

NASA Technical Reports Server (NTRS)

We develop numerical simulations of basaltic lava flowing laminarly over a basalt substrate in order to examine the details of the lava dynamics and thermal boundary layers and to understand the implications for substrate heating. As the initial stage of a larger study of thermomechanical erosion in different planetary environments, we aim to understand why erosion occurs on Earth, why erosion features are not ubiquitous given the high temperatures involved, and whether it is a plausible mechanism for the formation of planetary channels such as lunar sinuous rilles and Venusian canali. Here we confine our attention to terrestrial lavas with well-known properties and eruption parameters. With relatively simple computational fluid dynamic simulations, most closely representing tube-fed hawaiian basalts (for which erosion has been documented), we demonstrate the importance of incorporating several key factors in models of lava flow/ substrate heat transfer, which have commonly been neglected in previous treatments. By addressing the interaction of the flow dynamics and heat transfer in the lava, our work suggests that the development of a temperature gradient in the base of the lava, even for undeveloped flow, has a significant influence on substrate temperature. The sensitivity of the lava-substrate interface temperature to the thermophysical properties of the lava and substrate suggests that a delicate balance is required for partial melting to occur. Thus, it might take weeks of continuous flow to initiate partial melting of the substrate at distances of several kilometers from the vent. These durations exceed the periods of stability typical of lava flowing in tubes; pauses, blockages, surges, and break-outs frequently disrupt the flow. However, natural irregularities in the flow dynamics or substrate topography might help to initiate and maintain substrate melting on shorter timescales by disturbing the intimately coupled dynamic and thermal boundary layers. Although a purely thermal mechanism cannot be ruled out, our findings support the premise that mechanical erosion may play a key role in reports of erosion based on field evidence.

Fagents, S. A.; Greeley, R.; Lenat, J. F. (Editor)

2001-01-01

98

Transfer of radiocesium to four cruciferous vegetables as influenced by organic amendment under different field conditions in Fukushima Prefecture.  

PubMed

Soil-to-plant transfer of radiocesium ((137)Cs) in four cruciferous vegetables as influenced by cattle manure-based compost amendment was investigated. Komatsuna, mustard, radish and turnip were cultivated in three different (137)Cs-contaminated fields at Nihonmatsu City in Fukushima Prefecture from June to August 2012. Results revealed that organic compost amendments stimulated plant biomass production and tended to induce higher (137)Cs concentration in the cruciferous vegetables in most cases. Among the studied sites, Takanishi soil possessing low exchangeable potassium (0.10 cmolc kg(-1)) was associated with an increased concentration of (137)Cs in plants. Radiocesium transfer factor (TF) values of the vegetables ranged from 0.025 to 0.119. The increase in (137)Cs TFs was dependent on larger plant biomass production, high organic matter content, and high sand content in the studied soils. Average (137)Cs TF values for all study sites and compost treatments were higher in Komatsuna (0.072) and radish (0.059), which exhibited a higher biomass production compared to mustard and turnip. The transferability of (137)Cs to vegetables from soils was in the order Komatsuna > radish > mustard > turnip. The highest (137)Cs TF value (0.071) of all vegetables was recorded for a field where the soil had high organic matter content and a high clay proportion of 470 g kg(-1) consisting of Al-vermiculite clay mineral. PMID:25483355

Aung, Han Phyo; Djedidi, Salem; Yokoyama, Tadashi; Suzuki, Sohzoh; Bellingrath-Kimura, Sonoko Dorothea

2014-12-01

99

Work Environment Factors Influencing the Transfer of Learning for Online Learners  

ERIC Educational Resources Information Center

HRD professionals struggle with why a higher percentage of skills and knowledge acquired through training fail to transfer to the work environment and why transfer appears to diminish over time (Cromwell & Kolb, 2002). With increased investment in technology and professional development, it is imperative to enhance the learners' transfer process…

Gitonga, Jacqueline W.

2006-01-01

100

Analysis on Model and Affected Factors of Heat Transfer of Floor Heating System  

Microsoft Academic Search

High error in calculating the heat transfer of floor heating system can be introduced by existing models, considering the heat transfer of the floor slab and different temperature between interior wall and exterior wall. A modified calculation model of heat transfer of floor heating system was proposed, analyzed the influence of the interior or exterior wall and the floor slab,

Wu Guozhong; Xue Kang; Qi Hangbing; Li Dong

2010-01-01

101

Transfer of embryos into the uterus: How much do technical factors affect pregnancy rates?  

Microsoft Academic Search

Objective Our objective was to identify the effect on outcome of (a) ultrasound-assisted embryo transfer, (b) the use of different embryo transfer catheters, and (c) the length of time the patients remain in the supine position after embryo transfer.

Talha Al-Shawaf; Rajendra Dave; Joyce Harper; Deborah Linehan; Paul Riley; Ian Craft

1993-01-01

102

Coagulation factor X mediates adenovirus type 5 liver gene transfer in non-human primates (Microcebus murinus).  

E-print Network

Coagulation factor X mediates adenovirus type 5 liver gene transfer in non- human primates by Ad5 and FX-binding ablated Ad5 vectors in non-human primates. Ad5 vectors accumulated in and mediated particles predominantly accumulate in and transduce the liver in rodent and non-human primate models(5, 15

Boyer, Edmond

103

Learning What Matters: Exploring the Factors Affecting Learning Transfers in Child Welfare Competencies and Career Interest in Child Welfare  

ERIC Educational Resources Information Center

The understanding of the factors impacting MSW students' interests and motivation to learn child welfare competencies, and how they affect learning transfer of the subject is important for the development of a knowledgeable, competent, and committed workforce that serves children and families in the United States. Practitioners need to attain…

Liao, Aries Meng-Wei

2012-01-01

104

Perceptions of a Learning Organization and Factors within the Work Environment That Influence Transfer of Training in Law Enforcement  

ERIC Educational Resources Information Center

The purpose of this study was to determine law enforcement officers' perception of factors within the workplace that influence transfer of training and their perception of the organization being a learning organization. The study actually had three parts. First, it intended to investigate the perception of law enforcement officers regarding…

Hunter-Johnson, Yvonne

2012-01-01

105

Dynamic form factor of liquid4He at intermediate momentum transfer  

NASA Astrophysics Data System (ADS)

Measurements of the inelastic neutron scattering from liquid4He at T=1.2 K in the range of wavevector transfer 3? Q?12 Å-1 have been performed to verify the oscillations in the peak position and the width of the scattering function with Q observed by Cowley and Woods and by Martel et al. We confirm these oscillations and extend the measurements to show that the oscillations in the width continue up to Q?12 Å-1 while oscillations in the peak position, which have a much smaller amplitude, could be observed with confidence up to Q?8 Å-1 only. We also present a straightforward RPA calculation of the dynamic form factor S(Q, ?), beginning from the pair interatomic potential, to see how well the observed S(Q, ?) can be described and to investigate the origin of the oscillations. The observed S(Q, ?) is quite well reproduced and the oscillations in the width and peak position of S(Q, ?) are seen to originate from oscillations in the interaction in the RPA which we have approximated as the4He-4He scattering amplitude calculated from v(r). While the present calculation is quite different from the model proposed previously by Martel et al., the physical origin of the oscillations in S( Q, ?) is the same, namely oscillations in the4He-4He atom scattering amplitude.

Stirling, W. G.; Talbot, E. F.; Tanatar, B.; Glyde, H. R.

1988-10-01

106

Visualization of two transfer RNAs trapped in transit during elongation factor G-mediated translocation  

PubMed Central

During protein synthesis, coupled translocation of messenger RNAs (mRNA) and transfer RNAs (tRNA) through the ribosome takes place following formation of each peptide bond. The reaction is facilitated by large-scale conformational changes within the ribosomal complex and catalyzed by elongtion factor G (EF-G). Previous structural analysis of the interaction of EF-G with the ribosome used either model complexes containing no tRNA or only a single tRNA, or complexes where EF-G was directly bound to ribosomes in the posttranslocational state. Here, we present a multiparticle cryo-EM reconstruction of a translocation intermediate containing two tRNAs trapped in transit, bound in chimeric intrasubunit ap/P and pe/E hybrid states. The downstream ap/P-tRNA is contacted by domain IV of EF-G and P-site elements within the 30S subunit body, whereas the upstream pe/E-tRNA maintains tight interactions with P-site elements of the swiveled 30S head. Remarkably, a tight compaction of the tRNA pair can be seen in this state. The translocational intermediate presented here represents a previously missing link in understanding the mechanism of translocation, revealing that the ribosome uses two distinct molecular ratchets, involving both intra- and intersubunit rotational movements, to drive the synchronous movement of tRNAs and mRNA. PMID:24324168

Ramrath, David J. F.; Lancaster, Laura; Sprink, Thiemo; Mielke, Thorsten; Loerke, Justus; Noller, Harry F.; Spahn, Christian M. T.

2013-01-01

107

Imaging Erg and Jun transcription factor interaction in living cells using fluorescence resonance energy transfer analyses  

SciTech Connect

Physical interactions between transcription factors play important roles in modulating gene expression. Previous in vitro studies have shown a transcriptional synergy between Erg protein, an Ets family member, and Jun/Fos heterodimer, members of the bZip family, which requires direct Erg-Jun protein interactions. Visualization of protein interactions in living cells is a new challenge in biology. For this purpose, we generated fusion proteins of Erg, Fos, and Jun with yellow and cyan fluorescent proteins, YFP and CFP, respectively. After transient expression in HeLa cells, interactions of the resulting fusion proteins were explored by fluorescence resonance energy transfer microscopy (FRET) in fixed and living cells. FRET between YFP-Erg and CFP-Jun was monitored by using photobleaching FRET and fluorescence lifetime imaging microscopy. Both techniques revealed the occurrence of intermolecular FRET between YFP-Erg and CFP-Jun. This is stressed by loss of FRET with an YFP-Erg version carrying a point mutation in its ETS domain. These results provide evidence for the interaction of Erg and Jun proteins in living cells as a critical prerequisite of their transcriptional synergy, but also for the essential role of the Y371 residue, conserved in most Ets proteins, in this interaction.

Camuzeaux, Barbara [UMR 8526CNRS/Institut Pasteur de Lille/Universite de Lille2, Institut de Biologie de Lille, BP 447, 1 rue Calmette, 59021 Lille cedex (France); Spriet, Corentin [Service d'Imagerie Cellulaire Fonctionnelle, FRC3 CNRS, Institut de Biologie de Lille, BP 447, 1 rue Calmette, 59021 Lille cedex (France); Heliot, Laurent [Service d'Imagerie Cellulaire Fonctionnelle, FRC3 CNRS, Institut de Biologie de Lille, BP 447, 1 rue Calmette, 59021 Lille cedex (France); Coll, Jean [UMR 8527CNRS/Institut Pasteur de Lille/Universite de Lille2, Institut de Biologie de Lille, BP 447, 1 rue Calmette, 59021 Lille cedex (France); Duterque-Coquillaud, Martine [UMR 8526CNRS/Institut Pasteur de Lille/Universite de Lille2, Institut de Biologie de Lille, BP 447, 1 rue Calmette, 59021 Lille cedex (France)]. E-mail: martine.duterque@ibl.fr

2005-07-15

108

In Vivo and In Vitro studies on transfer factor with a protein antigen system  

E-print Network

subject was possible by transfer of serum. In the tuberculin type sensiti. vity he found that skin testing wi. th speci. fic antigen resulted in a delayed (24 to 48 hours) reaction, that antibodies were not demon- strable, and that passive transfer... leukocytes from sensi- tized donors to a nonsensitive recipient. These recipients, when skin tested with specific antigen, gave a typical delayed response. The passive transfer of the delayed hypersensitivity reaction with cells was later confirmed...

Kelleher, Peter Joseph

1975-01-01

109

Factors affecting the levels of protection transferred from mother to offspring following immune challenge  

PubMed Central

Introduction The transfer of antibodies from mother to offspring is key to protecting young animals from disease and can have a major impact on responses to infection and offspring fitness. Such maternal effects also allow young that may be exposed to disease in early life to focus resources on growth and development at this critical period of development. Maternally transferred antibodies are therefore an important source of phenotypic variation in host phenotype as well as influencing host susceptibility and tolerance to infection across generations. It has previously been assumed the transfer of antibodies is passive and invariant and reflects the level of circulating antibody in the mother at the time of transfer. However, whether females may vary in the relative amount of protection transferred to offspring has seldom been explored. Results Here we show that females differ widely in the relative amount of specific blood antibodies they transfer to the embryonic environment (range 9.2%-38.4% of their own circulating levels) in Chinese painted quail (Coturnix chinensis). Relative transfer levels were unrelated to the size of a female’s own immune response. Furthermore, individual females were consistent in their transfer level, both across different stages of their immune response and when challenged with different vaccine types. The amount of antibody transferred was related to female condition, but baseline antibody responses of mothers were not. However, we found no evidence for any trade-offs between the relative amount of antibody transferred with other measures of reproductive investment. Conclusions These results suggest that the relative amount of antibodies transferred to offspring can vary significantly and consistently between females. Levels of transfer may therefore be a separate trait open to manipulation or selection with potential consequences for offspring health and fitness in both wild and domesticated populations. PMID:25057280

2014-01-01

110

Gene Electro Transfer of Plasmid Encoding Vascular Endothelial Growth Factor for Enhanced Expression and Perfusion in the Ischemic Swine Heart  

PubMed Central

Myocardial ischemia can damage heart muscle and reduce the heart's pumping efficiency. This study used an ischemic swine heart model to investigate the potential for gene electro transfer of a plasmid encoding vascular endothelial growth factor for improving perfusion and, thus, for reducing cardiomyopathy following acute coronary syndrome. Plasmid expression was significantly greater in gene electro transfer treated tissue compared to injection of plasmid encoding vascular endothelial growth factor alone. Higher gene expression was also seen in ischemic versus non-ischemic groups with parameters 20 Volts (p<0.03), 40 Volts (p<0.05), and 90 Volts (p<0.05), but not with 60 Volts (p<0.09) while maintaining a pulse width of 20 milliseconds. The group with gene electro transfer of plasmid encoding vascular endothelial growth factor had increased perfusion in the area at risk compared to control groups. Troponin and creatine kinase increased across all groups, suggesting equivalent ischemia in all groups prior to treatment. Echocardiography was used to assess ejection fraction, cardiac output, stroke volume, left ventricular end diastolic volume, and left ventricular end systolic volume. No statistically significant differences in these parameters were detected during a 2-week time period. However, directional trends of these variables were interesting and offer valuable information about the feasibility of gene electro transfer of vascular endothelial growth factor in the ischemic heart. The results demonstrate that gene electro transfer can be applied safely and can increase perfusion in an ischemic area. Additional study is needed to evaluate potential efficacy. PMID:25545364

Navare, Sagar; Stratton, Michael; Murray, Len; Li, Fanying

2014-01-01

111

Analysis of the sequence and gene products of the transfer region of the F sex factor.  

PubMed Central

Bacterial conjugation results in the transfer of DNA of either plasmid or chromosomal origin between microorganisms. Transfer begins at a defined point in the DNA sequence, usually called the origin of transfer (oriT). The capacity of conjugative DNA transfer is a property of self-transmissible plasmids and conjugative transposons, which will mobilize other plasmids and DNA sequences that include a compatible oriT locus. This review will concentrate on the genes required for bacterial conjugation that are encoded within the transfer region (or regions) of conjugative plasmids. One of the best-defined conjugation systems is that of the F plasmid, which has been the paradigm for conjugation systems since it was discovered nearly 50 years ago. The F transfer region (over 33 kb) contains about 40 genes, arranged contiguously. These are involved in the synthesis of pili, extracellular filaments which establish contact between donor and recipient cells; mating-pair stabilization; prevention of mating between similar donor cells in a process termed surface exclusions; DNA nicking and transfer during conjugation; and the regulation of expression of these functions. This review is a compendium of the products and other features found in the F transfer region as well as a discussion of their role in conjugation. While the genetics of F transfer have been described extensively, the mechanism of conjugation has proved elusive, in large part because of the low levels of expression of the pilus and the numerous envelope components essential for F plasmid transfer. The advent of molecular genetic techniques has, however, resulted in considerable recent progress. This summary of the known properties of the F transfer region is provided in the hope that it will form a useful basis for future comparison with other conjugation systems. PMID:7915817

Frost, L S; Ippen-Ihler, K; Skurray, R A

1994-01-01

112

Assessing dynamic spectral causality by lagged adaptive directed transfer function and instantaneous effect factor.  

PubMed

It is of significance to assess the dynamic spectral causality among physiological signals. Several practical estimators adapted from spectral Granger causality have been exploited to track dynamic causality based on the framework of time-varying multivariate autoregressive (tvMVAR) models. The nonzero covariance of the model's residuals has been used to describe the instantaneous effect phenomenon in some causality estimators. However, for the situations with Gaussian residuals in some autoregressive models, it is challenging to distinguish the directed instantaneous causality if the sufficient prior information about the "causal ordering" is missing. Here, we propose a new algorithm to assess the time-varying causal ordering of tvMVAR model under the assumption that the signals follow the same acyclic causal ordering for all time lags and to estimate the instantaneous effect factor (IEF) value in order to track the dynamic directed instantaneous connectivity. The time-lagged adaptive directed transfer function (ADTF) is also estimated to assess the lagged causality after removing the instantaneous effect. In this study, we first investigated the performance of the causal-ordering estimation algorithm and the accuracy of IEF value. Then, we presented the results of IEF and time-lagged ADTF method by comparing with the conventional ADTF method through simulations of various propagation models. Statistical analysis results suggest that the new algorithm could accurately estimate the causal ordering and give a good estimation of the IEF values in the Gaussian residual conditions. Meanwhile, the time-lagged ADTF approach is also more accurate in estimating the time-lagged dynamic interactions in a complex nervous system after extracting the instantaneous effect. In addition to the simulation studies, we applied the proposed method to estimate the dynamic spectral causality on real visual evoked potential (VEP) data in a human subject. Its usefulness in time-variant spectral causality assessment was demonstrated through the mutual causality investigation of brain activity during the VEP experiments. PMID:24956616

Xu, Haojie; Lu, Yunfeng; Zhu, Shanan; He, Bin

2014-07-01

113

Dynamic form factor of liquid /sup 4/He at intermediate momentum transfer  

SciTech Connect

Measurements of the inelastic neutron scattering from liquid /sup 4/He at T = 1.2 K in the range of wavevector transfer 3 less than or equal to Q less than or equal to 12 /angstrom/ /sup /minus/1/ have been performed to verify the oscillations in the peak position and the width of the scattering function with Q observed by Cowley and Woods and by Martel et al. The authors confirm these oscillations and extend the measurements to show that the oscillations in the width continue up to Q approx. 12 /angstrom/ /sup /minus/1/ while oscillations in the peak position, which have a much smaller amplitude, could be observed with confidence up to Q approx. 8 /angstrom//sup /minus/1/ only. They also present a straightforward RPA calculation of the dynamic form factor S(Q, ..omega..), beginning from the pair interatomic potential, to see how well the observed S(Q, ..omega..) can be described and to investigate the origin of the oscillations. The observed S(Q, ..omega..) is quite well reproduced and the oscillations in the width and peak position of S(Q, ..omega..) are seen to originate from oscillations in the interaction in the RPA which they have approximated as the /sup 4/He-/sup 4/He scattering amplitude calculated from v(r). While the present calculation is quite different from the model proposed previously by Martel et al., the physical origin of the oscillations in S(Q, ..omega..) is the same, namely oscillations in the /sup 4/He-/sup 4/He atom scattering amplitude.

Stirling, W.G.; Talbot, E.F. Tanatar, B.; Glyde, H.R.

1988-10-01

114

Recoil polarization measurements of the proton electromagnetic form factor ratio to high momentum transfer  

E-print Network

The electromagnetic form factors of the nucleon characterize the effect of its internal structure on its response to an electromagnetic probe as studied in elastic electronnucleon scattering. These form factors are functions ...

Puckett, Andrew James Ruehe

2010-01-01

115

Nonviral Retrograde Gene Transfer of Human Hepatocyte Growth Factor Improves Neuropathic Pain-related Phenomena in Rats  

PubMed Central

Peripheral nerve injury occasionally causes chronic neuropathic pain with hyperalgesia and allodynia. However, its treatment is difficult. Here, we used a chronic constriction injury (CCI) model in rats to investigate the effects on experimental neuropathic pain of the human hepatocyte growth factor (HGF) gene delivered into the nervous system by retrograde axonal transport following its repeated intramuscular transfer, using liposomes containing the hemagglutinating virus of Japan (HVJ). CCI (control) rats exhibited marked mechanical allodynia and thermal hyperalgesia, and decreased blood flow in sciatic nerve and hind paw. All these changes were significantly reversed by HGF gene transfer. In the sciatic nerve in HGF-treated rats, the size-frequency distributions for myelinated and unmyelinated axons each showed a rightward shift, the number of myelinated axons >5 µm in diameter was significantly increased, and the mean diameter of unmyelinated axons was significantly increased (versus CCI rats). Levels of P2X3, P2X4, and P2Y1 receptor mRNAs, and of interleukin-6 (IL-6) and activating transcription factor 3 (ATF3) mRNAs, were elevated in the ipsilateral dorsal root ganglia and/or sciatic nerve by CCI, and these levels were decreased by HGF gene transfer. These results may point toward a potential new treatment strategy for chronic neuropathic pain in this model. PMID:18941443

Tsuchihara, Toyokazu; Ogata, Sho; Nemoto, Koichi; Okabayashi, Takatoshi; Nakanishi, Kuniaki; Kato, Naoki; Morishita, Ryuichi; Kaneda, Yasufumi; Uenoyama, Maki; Suzuki, Shinya; Amako, Masatoshi; Kawai, Toshiaki; Arino, Hiroshi

2008-01-01

116

CFD analysis of heat transfer and friction factor charaterstics in a circular tube fitted with horizontal baffles twisted tape inserts  

NASA Astrophysics Data System (ADS)

Swirl/vortex flow generator is an important form of passive augmentation techniques. Twisted-tape is one of the most important members of this form which is used extensively in different type heat exchangers. This paper reports the effect of twisted tape inserts on heat transfer and friction factor characteristics in circular tube under constant heat flux and laminar flow conditions using CFD simulation. Plain twisted tape inserts with twist ratios (y = 2.93, 3.91) and baffled twisted tape inserts with twist ratio (y = 2.93) have been used for the simulation using Fluent version 6.3.26. The results obtained by simulation matched with the literature correlations for plain tube with the discrepancy of less than ± 8% for Nusselt number and ± 6.25% for friction factor. The results have also revealed that the heat transfer in term of the Nusselt number enhanced with increases of Reynolds number, decreases of twist ratio and baffle insert. Among the various twist ratios, the twisted tape with twist ratio of y=2.93 and baffle is offered a maximum heat transfer enhancement.

Salman, Sami D.; Kadhum, Abdul Amir H.; Takriff, Mohd S.; Bakar Mohamad, Abu

2013-12-01

117

Heat transfer and friction factor correlations for a solar air heater duct roughened artificially with multiple v-ribs  

SciTech Connect

The use of artificial roughness on the underside of the absorber plate is an effective and economic way to improve the thermal performance of a solar air heater. Several experimental investigations, involving different types of roughness elements, have been carried out to improve the heat transfer from the absorber plate to air flowing in solar air heaters. This paper presents an experimental investigation carried out to study the effect of multiple v-rib roughness on heat transfer coefficient and friction factor in an artificially roughened solar air heater duct. The experiment encompassed Reynolds number (Re) from 2000 to 20000, relative roughness height (e/D) values of 0.019-0.043, relative roughness pitch (P/e) range of 6-12, angle of attack ({alpha}) range of 30-75 and relative roughness width (W/w) range of 1-10. Extensive experimentation has been conducted to collect data on heat transfer and fluid flow characteristics of a rectangular duct roughened with multiple v-ribs. Using these experimental data, correlations for Nusselt number and friction factor in terms of roughness geometry and flow parameters have been developed. (author)

Hans, V.S. [Department of Mechanical Engineering, PAU, Ludhiana (Punjab) 141004 (India); Saini, R.P. [Alternate Hydro Energy Centre, Indian Institute of Technology, Roorkee (UA) 247667 (India); Saini, J.S. [Mechanical and Industrial Engineering Department, Indian Institute of Technology, Roorkee (UA) 247667 (India)

2010-06-15

118

In utero gene transfer reveals survival effects of nerve growth factor on rat brain cholinergic neurones during development.  

PubMed

Nerve growth factor (NGF) is a maintenance factor for cholinergic neurones in the brain, but its properties as a developmental survival factor are largely unknown. The low accessibility of the developing mammalian brain to experimental manipulation makes it difficult to increase NGF levels during the early phases of brain development. In the present study we have used an in utero, ex-vivo gene transfer approach to explore NGF actions during development of the cholinergic system in the rat brain. Significantly increased numbers of cholinergic neurones were found only in the mesopontine complex in animals receiving NGF-secreting transplants, whereas the cholinergic neurones in the basal forebrain and striatum were not clearly affected. The present results suggest that overexpression of NGF during development may promote the survival of distinct populations of central cholinergic neurones into adulthood. PMID:9753135

Martínez-Serrano, A; Olsson, M; Gates, M A; Björklund, A

1998-01-01

119

Electronic and nuclear factors in intramolecular charge and excitation transfer processes  

Microsoft Academic Search

A qualitative discussion is given of initial work on the following topics: intramolecular triplet excitation transfer bands, donor - bridge - acceptor systems with a tethered ion, and depolarization of transient microwave conductivity. A number of special compounds were synthesized, such as spiranes; 2,6-diamino- dihydro anthracene precursor; and para- amino- nitro- biphenyl and -terphenyl.

P. Piotrowiak

1993-01-01

120

EXPERIMENTAL METHODOLOGIES AND PRELIMINARY TRANSFER FACTOR DATA FOR ESTIMATION OF DERMAL EXPOSURES TO PARTICLES  

EPA Science Inventory

Developmental efforts and experimental data are described that focused on quantifying the transfer of particles on a mass basis from indoor surfaces to human skin. Methods were developed that utilized a common fluorescein-tagged Arizona Test Dust (ATD) as a possible surrogate ...

121

Influence of climatic factors on heat transfer in the upper zone of ground accumulators of heat  

NASA Astrophysics Data System (ADS)

The boundary-value problem of nonstationary heat conduction in the upper zone of ground accumulators of heat has been formulated and solved numerically with account for the action of the net flux of solar radiation and convective component of heat transfer on the Earth's surface.

Nakorchevskii, A. I.

2012-03-01

122

Biotic interactions modify the transfer of cesium-137 in a soil-earthworm-plant-snail food web.  

PubMed

The present study investigated the possible influence of the earthworm Aporrectodea tuberculata on the transfer of cesium-137 ((137)Cs) from a contaminated (130 Bq/kg) deciduous forest soil to the lettuce Lactuca sativa and to the snail Cantareus aspersus (formerly Helix aspersa) in two laboratory experiments. In the first experiment, the International Organization for Standardization 15952 test was used to expose snails for five weeks to contaminated soil with or without earthworms. In these conditions, the presence of earthworms caused a two- to threefold increase in (137)Cs concentrations in snails. Transfer was low in earthworms as well as in snails, with transfer factors (TFs) lower than 3.7 x 10(-2). Activity concentrations were higher in earthworms (2.8- 4.8 Bq/kg dry mass) than in snails (<1.5 Bq/kg). In the second experiment, microcosms were used to determine the contribution of soil and lettuce in the accumulation of (137)Cs in snails. Results suggest that the contribution of lettuce and soil is 80 and 20%, respectively. Microcosms also were used to study the influence of earthworms on (137)Cs accumulation in snail tissues in the most ecologically relevant treatment (soil-earthworm-plant-snail food web). In this case, soil-to-plant transfer was high, with a TF of 0.8, and was not significantly modified by earthworms. Conversely, soil-to-snail transfer was lower (TF, approximately 0.1) but was significantly increased in presence of earthworms. Dose rates were determined in the microcosm study with the EDEN (elementary dose evaluation for natural environment) model. Dose rates were lower than 5.5 x 10(-4) mGy/d, far from values considered to have effects on terrestrial organisms (1 mGy/d). PMID:18266477

Fritsch, Clémentine; Scheifler, Renaud; Beaugelin-Seiller, Karine; Hubert, Philippe; Coeurdassier, Michaël; de Vaufleury, Annette; Badot, Pierre-Marie

2008-08-01

123

Summarizing lecture: factors influencing enzymatic H-transfers, analysis of nuclear tunnelling isotope effects and thermodynamic versus specific effects  

PubMed Central

In the articles in this Discussion, a wide variety of topics are treated, including reorganization energy, initially introduced for electron transfers (‘environmentally assisted tunnelling’), nuclear tunnelling, H/D and C12/C13 kinetic isotope effects (KIEs), the effect of changes of distal and nearby amino acid residues using site-directed mutagenesis, and dynamics versus statistical effects. A coordinate-free form of semi-classical theory is used to examine topics on data such as tunnelling versus ‘over-the-barrier’ paths and temperature and pressure effects on KIEs. The multidimensional semi-classical theory includes classically allowed and classically forbidden transitions. More generally, we address the question of relating kinetic to thermodynamic factors, as in the electron transfer field, so learning about specific versus thermodynamic effects in enzyme catalysis and KIEs. PMID:16873131

Marcus, R.A

2006-01-01

124

The Use of Iteration Factors Method in the Solution of Multilevel Radiative Transfer Problems in Stellar Atmospheres  

NASA Astrophysics Data System (ADS)

The NLTE problem of formation of spectral lines is one of the most difficult ones to deal with; due to the important role of scattering processes it is nonlocal and for the multilevel case it is additionally nonlinear. Therefore, the problem requires simultaneous solution of radiative transfer (RT) and statistical equilibrium (SE) equations which can be achieved through iterative procedure. There is still a great need of efficient numerical methods for a solution of NLTE radiative transfer problems as they are a necessary step of stellar atmospheres modelling and other important astrophysical problems. In the thesis we develop fast and accurate numerical method that uses iteration factors. The method is based on the use of quasi-invariant functions - iteration factors, in a simple iterative procedure. Defined as ratios of the moments (integrals of angles and frequencies) of radiation field intensities, the factors are calculated on the beginning of each iterative step from the current solution and then used to obtain its correction. In the thesis we extend iteration factors method developed for a solution of linear problems - monochromatic problem and two-level atom line transfer problems to the solution of a more generalized multilevel problem of spectral line formation with complete redistribution and no background continuum. The additional difficulty arises from the non linear coupling of atomic level populations and the radiation filed intensities in the corresponding spectral lines. In the thesis we suggest and describe in details four iterative procedures that use two families of iteration factors defined for a constant property medium and two different approaches for a simultaneous solution of nonlinear RT and SE equations: (1) linearization of the equations with respect to all relevant variables and (2) modification of the SE equations in order to make them linear. In both approaches the substitution of the linearized SE equations in the moments of RT equation results in a tridiagonal system that is solved, together with the boundary conditions, by a standard Gaussian elimination procedure. In order to test the convergence properties and accuracy of the suggested procedures we solved a standard benchmark problem of spectral line formation by three-level hydrogen atom in plan-parallel isothermal atmosphere with no background continuum and compared its solutions with those obtained by other methods that solved the same test problem. Additionally we solved the problem of spectral line formation by CaII ions with five levels. We also compared the speed of convergence and the total computational time of our method with those of some other methods in use. Finally, we formulated and analyzed a more general line transfer problem in variably property atmosphere with background continuum. For its solution we defined four additional families of iteration factors and tested the convergence properties of the procedures that use them on a solution of linear radiative transfer problem for constant and for variable (with optical depth) absorption profile, as well as on multilevel case. In the conclusion we emphasized that the use of the iteration factors defined in the thesis results in extremely fast convergence to the exact solutions of the problem, with no need of extra mathematical acceleration, necessary for other methods. Also, the use of iteration factors defined for the spectral line as a whole drastically reduces the memory cost and the computational time. The accuracy of the method increases with the number of the grid points, but the very high convergence speed is not affected by the refinement of the grid resolution. So the total computational work scales linearly with the number of the grid points and is couple of times less than needed by other existing methods.

Kuzmanovska-Barandovska, O.

2012-12-01

125

Intravenous somatic gene transfer with antisense tissue factor restores blood flow by reducing tumor necrosis factor-induced tissue factor expression and fibrin deposition in mouse meth-A sarcoma.  

PubMed Central

Fibrin is deposited on the endothelial cell surface in the vasculature of murine methylcholanthrene A-induced sarcomas after injection of tumor necrosis factor (TNF). Capillary endothelial cells of the tumor vascular bed become positive for tissue factor after TNF injection, based on immunocytochemistry and in situ hybridization. Intravascular clot formation was not dependent on tissue factor derived from tumor cells, since in vessels of tumors not expressing tissue factor, TNF also induced fibrin/fibrinogen deposition. However, the time course of fibrin/fibrinogen deposition after TNF differed in tumors expressing no, little, or greater amounts of tissue factor. Fibrin/fibrinogen deposition was more rapid in tumors in which the neoplastic cells expressed tissue factor than in tumors not expressing tissue factor. In the tumors not expressing tissue factor, activation of coagulation was dependent on TNF-induced synthesis of tissue factor by host cells, i.e., endothelium or monocytes/macrophages. Intravenous somatic gene transfer with tissue factor cDNA in the antisense orientation (but not sense or vector alone) reduced intravascular fibrin/fibrinogen deposition and restored blood flow to the tumor, showing that de novo tissue factor expression is central in TNF-induced activation of the coagulation mechanism. PMID:8636400

Zhang, Y.; Deng, Y.; Wendt, T.; Liliensiek, B.; Bierhaus, A.; Greten, J.; He, W.; Chen, B.; Hach-Wunderle, V.; Waldherr, R.; Ziegler, R.; Männel, D.; Stern, D. M.; Nawroth, P. P.

1996-01-01

126

Tube side heat transfer coefficient and friction factor characteristics of horizontal tubes with helical rib  

Microsoft Academic Search

The results of the heat transfer and pressure drop characteristics in horizontal double pipes with helical ribs are presented. Nine test sections with different characteristic parameters of: helical rib height to diameter, ?\\/di=0.12, 0.15, 0.19, and helical rib pitch to diameter, p\\/di=1.05, 0.78, 0.63, are tested. Cold and hot water are used as working fluids in the shell side and

Paisarn Naphon; Manachai Nuchjapo; Jutarat Kurujareon

2006-01-01

127

Evaluation of the conduction shape factor with a CFD code for a liquid–metal heat transfer in heated triangular rod bundles  

Microsoft Academic Search

A heat transfer due to conduction through a coolant itself is not negligible in a liquid–metal cooled reactor (LMR). This portion of a heat transfer is frequently described with a conduction shape factor during the thermal-hydraulic design of an LMR. The conduction shape factor, which is highly dependent on a pitch-to-diameter (P\\/D) ratio, is defined as the ratio of the

Hae-yong Jeong; Kwi-seok Ha; Young-min Kwon; Yong-bum Lee; Dohee Hahn; James E. Cahalan; Floyd E. Dunn

2007-01-01

128

Measurements of the meson-photon transition form factors of light pseudoscalar mesons at large momentum transfer  

E-print Network

PHYSICAL REVIEW D 1 JANUARY 1998VOLUME 57, NUMBER 1Measurements of the meson-photon transition form factors of light pseudoscalar mesons at large momentum transfer J. Gronberg, T. S. Hill, R. Kutschke, D. J. Lange, S. Menary, R. J. Morrison, H. N.... Nelson, T. K. Nelson, C. Qiao, J. D. Richman, D. Roberts, A. Ryd, and M. S. Witherell University of California, Santa Barbara, California 93106 R. Balest, B. H. Behrens, W. T. Ford, H. Park, J. Roy, and J. G. Smith University of Colorado, Boulder...

Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Hancock, N.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan

1998-01-01

129

SiC MOSFET Based Single Phase Active Boost Rectifier with Power Factor Correction for Wireless Power Transfer Applications  

SciTech Connect

Wireless Power Transfer (WPT) technology is a novel research area in the charging technology that bridges the utility and the automotive industries. There are various solutions that are currently being evaluated by several research teams to find the most efficient way to manage the power flow from the grid to the vehicle energy storage system. There are different control parameters that can be utilized to compensate for the change in the impedance due to variable parameters such as battery state-of-charge, coupling factor, and coil misalignment. This paper presents the implementation of an active front-end rectifier on the grid side for power factor control and voltage boost capability for load power regulation. The proposed SiC MOSFET based single phase active front end rectifier with PFC resulted in >97% efficiency at 137mm air-gap and >95% efficiency at 160mm air-gap.

Onar, Omer C [ORNL] [ORNL; Tang, Lixin [ORNL] [ORNL; Chinthavali, Madhu Sudhan [ORNL] [ORNL; Campbell, Steven L [ORNL] [ORNL; Miller (JNJ), John M. [JNJ-Miller PLC] [JNJ-Miller PLC

2014-01-01

130

Gene transfer of antisense hypoxia inducible factor-1 ? enhances the therapeutic efficacy of cancer immunotherapy  

Microsoft Academic Search

Solid tumors meet their demands for nascent blood vessels and increased glycolysis, to combat hypoxia, by activating multiple genes involved in angiogenesis and glucose metabolism. Hypoxia inducible factor-1 (HIF-1) is a constitutively expressed basic helix–loop–helix transcription factor, formed by the assembly of HIF-1? and HIF-1? (Arnt), that is stablized in response to hypoxia, and rapidly degraded under normoxic conditions. It

X Sun; J R Kanwar; E Leung; K Lehnert; D Wang; G W Krissansen

2001-01-01

131

Transforming Growth Factor ? Neutralization within Cardiac Allografts by Decorin Gene Transfer Attenuates Chronic Rejection1  

PubMed Central

Chronic allograft rejection (CR) is the leading cause of late graft failure following organ transplantation. CR is a progressive disease, characterized by deteriorating graft function, interstitial fibrosis, cardiac hypertrophy and occlusive neointima development. TGF?, known for its immunosuppressive qualities, plays a beneficial role in the transplant setting by maintaining alloreactive T cells in a hyporesponsive state, but has also been implicated in promoting graft fibrosis and CR. In the mouse vascularized cardiac allograft model, transient depletion of CD4+ cells promotes graft survival but leads to CR, which is associated with intragraft TGF? expression. Decorin, an extracellular matrix protein, inhibits both TGF? bioactivity and gene expression. In this study, gene transfer of decorin into cardiac allografts was employed to assess the impact of intragraft TGF? neutralization on CR, systemic donor-reactive T cell responses, and allograft acceptance. Decorin gene transfer and neutralization of TGF? in cardiac allografts significantly attenuated interstitial fibrosis, cardiac hypertrophy and improved graft function, but did not result in systemic donor-reactive T cell responses. Thus, donor-reactive T and B cells remained in a hyporesponsive state. These findings indicate that neutralizing intragraft TGF? inhibits the cytokine's fibrotic activities, but does not reverse its beneficial systemic immunosuppressive qualities. PMID:19917705

Faust, Susan M.; Lu, Guanyi; Wood, Sherri C.; Bishop, D. Keith

2011-01-01

132

An Exploratory, Scoping Study into the Human Factors Issues of Transferring Medical Capability into Community Settings  

Microsoft Academic Search

The Population of the western world is ageing. Medical capability is increasingly being moved into the community. The interaction of these two factors has implications for safety and usability of medical products and of the systems which will support healthcare in the community. This study aims to explore the issues of systems of healthcare and medical products from the point

Claire Munro

133

An Integrated Model of Transcription Factor Diffusion Shows the Importance of Intersegmental Transfer and Quaternary Protein Structure for Target Site Finding  

PubMed Central

We present a computational model of transcription factor motion that explains both the observed rapid target finding of transcription factors, and how this motion influences protein and genome structure. Using the Smoldyn software, we modelled transcription factor motion arising from a combination of unrestricted 3D diffusion in the nucleoplasm, sliding along the DNA filament, and transferring directly between filament sections by intersegmental transfer. This presents a fine-grain picture of the way in which transcription factors find their targets two orders of magnitude faster than 3D diffusion alone allows. Eukaryotic genomes contain sections of nucleosome free regions (NFRs) around the promoters; our model shows that the presence and size of these NFRs can be explained as their acting as antennas on which transcription factors slide to reach their targets. Additionally, our model shows that intersegmental transfer may have shaped the quaternary structure of transcription factors: sequence specific DNA binding proteins are unusually enriched in dimers and tetramers, perhaps because these allow intersegmental transfer, which accelerates target site finding. Finally, our model shows that a ‘hopping’ motion can emerge from 3D diffusion on small scales. This explains the apparently long sliding lengths that have been observed for some DNA binding proteins observed in vitro. Together, these results suggest that transcription factor diffusion dynamics help drive the evolution of protein and genome structure. PMID:25333780

Schmidt, Hugo G.; Sewitz, Sven; Andrews, Steven S.; Lipkow, Karen

2014-01-01

134

Molecular factors influencing drug transfer across the blood-brain barrier.  

PubMed

A recently reported approach to the prediction of blood-brain drug distribution uses the general linear free energy equation to correlate equilibrium blood-brain solute distributions (logBB) with five solute descriptors: R2 an excess molar refraction term; pi2H, solute dipolarity or polarizability; alpha2H and beta2H, the hydrogen bond acidity or basicity, and Vx, the solute McGowan volume. In this study we examine whether the model can be used to analyse kinetic transfer rates across the blood-brain barrier in the rat. The permeability (logPS) of the blood-brain barrier to a chemically diverse series of compounds was measured using a short duration vascular perfusion method. LogPS data were correlated with calculated solute descriptors, and octanol-water partition coefficients (logP(oct)) for comparison. It is shown that a general linear free energy equation can be constructed to predict and interpret logPS values. The utility of this model over other physicochemical descriptors for interpreting logPS and logBB values is discussed. PMID:9466345

Gratton, J A; Abraham, M H; Bradbury, M W; Chadha, H S

1997-12-01

135

Development of a general equation to determine the transfer factor feed-to-meat for radiocesium on the basis of the body mass of domestic animals  

SciTech Connect

Transfer factors from feed to meat (5{sub {integral}}), taken from literature for monogastric animals and ruminants have been correlated to their corresponding animal body mass (m{sub b}). Taking all data into account, a close relationship between both transfer factor and body mass becomes evident, yielding a regression function of (T{sub {integral}} = 8.0 x m{sub b}{sup {minus}0.91}) (r = -0.97). For monogastric animals (including poultry), the corresponding relationships are T{sub {integral}} = 1.9 x m{sub b}{sup {minus}0.72} (r = 0.78). The equations offer the opportunity to estimate the transfer factor for individual animals more precisely taking individual body masses into account. They are of interest for animals, on which no or only poor data concerning radiocesium transfer factors are available. The determination of radiocesium transfer factors are reduced to a simple weighing process. 17 refs., 1 fig., 2 tabs.

Nalezinski, S.; Ruehm, W.; Wirth, E. [Institut fuer STrahlenhygiene, Neuherberg/Oberschleibheim (Germany)

1996-05-01

136

Comparable frequencies of coding mutations and loss of imprinting in human pluripotent cells derived by nuclear transfer and defined factors.  

PubMed

The recent finding that reprogrammed human pluripotent stem cells can be derived by nuclear transfer into human oocytes as well as by induced expression of defined factors has revitalized the debate on whether one approach might be advantageous over the other. Here we compare the genetic and epigenetic integrity of human nuclear-transfer embryonic stem cell (NT-ESC) lines and isogenic induced pluripotent stem cell (iPSC) lines, derived from the same somatic cell cultures of fetal, neonatal, and adult origin. The two cell types showed similar genome-wide gene expression and DNA methylation profiles. Importantly, NT-ESCs and iPSCs had comparable numbers of de novo coding mutations, but significantly more than parthenogenetic ESCs. As iPSCs, NT-ESCs displayed clone- and gene-specific aberrations in DNA methylation and allele-specific expression of imprinted genes. The occurrence of these genetic and epigenetic defects in both NT-ESCs and iPSCs suggests that they are inherent to reprogramming, regardless of derivation approach. PMID:25517467

Johannesson, Bjarki; Sagi, Ido; Gore, Athurva; Paull, Daniel; Yamada, Mitsutoshi; Golan-Lev, Tamar; Li, Zhe; LeDuc, Charles; Shen, Yufeng; Stern, Samantha; Xu, Nanfang; Ma, Hong; Kang, Eunju; Mitalipov, Shoukhrat; Sauer, Mark V; Zhang, Kun; Benvenisty, Nissim; Egli, Dieter

2014-11-01

137

Culture factors affecting the success rate of in vitro fertilization and embryo transfer.  

PubMed

The development of one-cell mouse zygotes to the blastocyst stage in vitro has been used as a quality control for the media and handling procedures employed for human in vitro fertilization and embryo transfer (IVF/ET). One-cell mouse zygotes were placed in culture in medium containing bovine serum albumin. Aliquots of the same batch of medium containing female patients' homologous serum were used for the fertilization and culture of human oocytes. The following procedures were associated with high rates of mouse embryo development and human pregnancies following IVF/ET: adequate gassing and equilibration of the medium, double-rinsing of pipets and catheters used to handle embryos, use of a HEPES-buffered medium for manipulating embryos in the absence of an atmosphere containing 5% CO2, control of excessive temperature in the vicinity of the embryos, and ET using medium containing 50% patient's serum. The institution of these procedures gave more consistent pregnancy rates. However, there was no obvious association between fertilization and cleavage of human oocytes and the quality of the medium ascertained by the mouse embryo development test. In a continuing trial, we are comparing two culture media (modified Tyrode's and a medium formulated on the composition of human fallopian tube fluid [HTF]) and two culture techniques (culture in medium under oil in petri dishes and in loosely capped tubes). Significantly more mouse zygotes developed in HTF medium compared to Tyrode's medium. In a randomized 2 X 2 factorial trial with human IVF/ET, the highest pregnancy rate occurred when fertilization and culture were carried out in HTF medium under oil, but numbers are not yet sufficient to show any statistical difference between treatments. PMID:3860035

Quinn, P; Warnes, G M; Kerin, J F; Kirby, C

1985-01-01

138

Transfer of human hepatocyte growth factor reduces inflammation and prevents pulmonary arterial remodeling in monocrotaline-induced  

PubMed Central

Inflammation and endothelial dysfunction contribute to the pathogenesis and development of pulmonary arterial hypertension (PAH). This study was to investigate the therapeutic effect of human hepatocyte growth factor (HGF) gene transfer on monocrotaline (MCT) induced PAH rat models. PAH was induced by injecting MCT for 4 weeks. The rats were randomly assigned to phosphate buffered saline control group, MCT group, and HGF treatment group. After 2 weeks of induction, measures of mean pulmonary artery pressure (mPAP), weight ratio of the RV to the LV plus septum, percent wall thickness index (TI) and area index (AI) were significantly increased in MCT-group and HGF treatment-group compared with those in control group (P < 0.05). Those measurements in MCT-group were significantly higher than those in HGF treatment-group (P < 0.05). IL-6 significantly decreased in HGF treatment-group compared with MCT-group, but higher than that of control group (all P < 0.05). IL-10 in HGF treatment-group significantly increased compared with MCT-group, but lower than that of control group (all P < 0.05). Endothelial microparticles (EMP) started to decrease in the HGF treatment-group 3 days after treatment and was most significant after 1 and 2 weeks of treatment (all P < 0.05). Our results showed that transfer of human HGF may attenuate the inflammatory cell infiltrate, reduce the expression of inflammatory factors, and those effects are possibly due to the inhibition of EMP production which may decrease pulmonary vascular wall damage in PAH.

Chen, Jianying; Zhang, Hongzhe; Zhang, Rujun; Liu, Zhenjun; Wang, Junxian; Xiao, Mengyuan; Ba, Mingchuan; Yao, Feng; Liu, Jinghu; Huang, Shi’an; Zhong, Jixin

2014-01-01

139

JLab Measurement of the 4He Charge Form Factor at Large Momentum Transfers  

SciTech Connect

The charge form factor of 4He has been extracted in the range 29 fm-2 <= Q2 <= 77 fm-2 from elastic electron scattering, detecting 4He nuclei and electrons in coincidence with the High Resolution Spectrometers of the Hall A Facility of Jefferson Lab. The results are in qualitative agreement with realistic meson-nucleon theoretical calculations. The data have uncovered a second diffraction minimum, which was predicted in the Q2 range of this experiment, and rule out conclusively long-standing predictions of dimensional scaling of high-energy amplitudes using quark counting.

Camsonne, Alexandre; Katramatou, A. T.; Olson, M.; Sparveris, Nikolaos; Acha, Armando; Allada, Kalyan; Anderson, Bryon; Arrington, John; Baldwin, Alan; Chen, Jian-Ping; Choi, Seonho; Chudakov, Eugene; Cisbani, Evaristo; Craver, Brandon; Decowski, Piotr; Dutta, Chiranjib; Folts, Edward; Frullani, Salvatore; Garibaldi, Franco; Gilman, Ronald; Gomez, Javier; Hahn, Brian; Hansen, Jens-Ole; Higinbotham, Douglas; Holmstrom, Timothy; Huang, Jian; Iodice, Mauro; Kelleher, Aidan; Khrosinkova, Elena; Kievsky, A.; Kuchina, Elena; Kumbartzki, Gerfried; Lee, Byungwuek; LeRose, John; Lindgren, Richard; Lott, Gordon; Lu, H.; Marcucci, Laura; Margaziotis, Demetrius; Markowitz, Pete; Marrone, Stefano; Meekins, David; Meziani, Zein-Eddine; Michaels, Robert; Moffit, Bryan; Norum, Blaine; Petratos, Gerassimos; Puckett, Andrew; Qian, Xin; Rondon-Aramayo, Oscar; Saha, Arunava; Sawatzky, Bradley; Segal, John; Hashemi, Mitra; Shahinyan, Albert; Solvignon-Slifer, Patricia; Subedi, Ramesh; Suleiman, Riad; Sulkosky, Vincent; Urciuoli, Guido; Viviani, Michele; Wang, Y.; Wojtsekhowski, Bogdan; Yan, X.; Yao, H.; Zhang, W. -M.; Zheng, X.; Zhu, L.

2014-04-01

140

The K?? vector form factor at zero momentum transfer on the lattice  

NASA Astrophysics Data System (ADS)

We present a quenched lattice study of the form factors f(q) and f(q) of the matrix elements . We focus on the second-order SU(3)-breaking quantity [1-f(0)], which is necessary to extract |V| from K decays. For this quantity we show that it is possible to reach the percent precision which is the required one for a significant determination of |V|. The leading quenched chiral logarithms are corrected for by using analytic calculations in quenched chiral perturbation theory. Our final result, f+K?(0)=0.960±0.005±0.007, where the systematic error does not include the residual quenched effects, is in good agreement with the estimate made by Leutwyler and Roos. A comparison with other non-lattice computations and the impact of our result on the extraction of |V| are also presented.

Be?irevi?, D.; Isidori, G.; Lubicz, V.; Martinelli, G.; Mescia, F.; Simula, S.; Tarantino, C.; Villadoro, G.

2005-01-01

141

The K?? vector form factor at zero momentum transfer on the lattice  

NASA Astrophysics Data System (ADS)

We present the first lattice QCD estimate of the form factor f(0), which is the key theoretical ingredient to extract |V| from K3 decays. Our result, f+K?(0)=0.960±0.005±0.007, is in good agreement with the model estimate by Leutwyler and Roos and with the recent QCD sum rule estimate. After combining recent experimental results with our value for f+K?(0), we could verify the unitarity of the first row of the CKM matrix, namely |+|+|=0.9997(14). To make our estimate fully model independent we need to remove the quenched approximation and use ever lower quark masses (keeping, however, finite volume effects under control).

Be?irevi?, D.; Isidori, G.; Lubicz, V.; Martinelli, G.; Mescia, F.; Simula, S.; Tarantino, C.; Villadoro, G.; SPQcdR Collaboration

2005-03-01

142

Protein film voltammetry and co-factor electron transfer dynamics in spinach photosystem II core complex.  

PubMed

Direct protein film voltammetry (PFV) was used to investigate the redox properties of the photosystem II (PSII) core complex from spinach. The complex was isolated using an improved protocol not used previously for PFV. The PSII core complex had high oxygen-evolving capacity and was incorporated into thin lipid and polyion films. Three well-defined reversible pairs of reduction and oxidation voltammetry peaks were observed at 4 °C in the dark. Results were similar in both types of films, indicating that the environment of the PSII-bound cofactors was not influenced by film type. Based on comparison with various control samples including Mn-depleted PSII, peaks were assigned to chlorophyll a (Chl a) (Em = -0.47 V, all vs. NHE, at pH 6), quinones (-0.12 V), and the manganese (Mn) cluster (Em = 0.18 V). PFV of purified iron heme protein cytochrome b-559 (Cyt b-559), a component of PSII, gave a partly reversible peak pair at 0.004 V that did not have a potential similar to any peaks observed from the intact PSII core complex. The closest peak in PSII to 0.004 V is the 0.18 V peak that was found to be associated with a two-electron process, and thus is inconsistent with iron heme protein voltammetry. The -0.47 V peak had a peak potential and peak potential-pH dependence similar to that found for purified Chl a incorporated into DMPC films. The midpoint potentials reported here may differ to various extents from previously reported redox titration data due to the influence of electrode double-layer effects. Heterogeneous electron transfer (hET) rate constants were estimated by theoretical fitting and digital simulations for the -0.47 and 0.18 V peaks. Data for the Chl a peaks were best fit to a one-electron model, while the peak assigned to the Mn cluster was best fit by a two-electron/one-proton model. PMID:23625504

Zhang, Yun; Magdaong, Nikki; Frank, Harry A; Rusling, James F

2014-05-01

143

Electromagnetic structure of the proton, pion, and kaon by high-precision form factor measurements at large timelike momentum transfers.  

PubMed

The electromagnetic structure of the lightest hadrons, proton, pion, and kaon is studied by high-precision measurements of their form factors for the highest timelike momentum transfers of |Q2|=s=14.2 and 17.4??GeV2. Data taken with the CLEO-c detector at sqrt[s]=3.772 and 4.170 GeV, with integrated luminosities of 805 and 586??pb(-1), respectively, have been used to study e+ e- annihilations into ?+ ?-, K+ K-, and pp. The dimensional counting rule prediction that at large Q2 the quantity Q2F(Q2) for pseudoscalar mesons is nearly constant, and should vary only weakly as the strong coupling constant ?S(Q2) is confirmed for both pions and kaons. However, the measurements are in strong quantitative disagreement with the predictions of the existing quantum chromodynamics-based models. For protons, it is found that the timelike form factors continue to remain nearly twice as large as the corresponding spacelike form factors measured in electron elastic scattering, in significant violation of the expectation of their equality at large Q2. Further, in contrast to pions and kaons, a significant difference is observed between the values of the corresponding quantity |Q4|G(M)(|Q2|)/?(p) for protons at |Q2|=14.2 and 17.4??GeV2. The results suggest the constancy of |Q2|G(M)(|Q2|)/?(p), instead, at these large |Q2|. PMID:23383892

Seth, Kamal K; Dobbs, S; Metreveli, Z; Tomaradze, A; Xiao, T; Bonvicini, G

2013-01-11

144

A potential screening factor for accumulation of cholesteyl ester transfer protein deficiency in East Asia: Schistosoma japonicum.  

PubMed

Cholesteryl ester transfer protein (CETP)-deficiency manifests a unique plasma lipoprotein profile without other apparent symptoms. It is highly common in East Asia while rather rare anywhere else. A potential environmental screening factor(s) may therefore contribute to this eccentric distribution, such as its selective advantage against a regional illness, most likely an infectious disease, in relation to plasma lipoproteins. Blood flukes use the host plasma lipoproteins as nutrient sources through the lipoprotein receptor-like systems. Its Asian-specific species, Schistosoma (S) japonicum, which has been endemic in East Asia, takes up cholesteryl ester (CE) from high-density lipoprotein (HDL) for the embryonation of their eggs to miracidia, a critical step of the hepatic pathogenesis of this parasite, but poorly from HDL of CETP-deficiency. CD36-related protein (CD36RP) was cloned from the adults and the eggs of S. japonicum, with 1880-bp encoding 506 amino-acid residues exhibiting the CD36 domains and two transmembrane regions. Its extracellular domain selectively bound human HDL but neither LDL nor CETP-deficiency HDL, and the antibody against the extracellular domain suppressed the selective HDL-CE uptake and embryonation of the eggs. When infected with S. japonicum, wild-type mice developed less hepatic granulomatosis than CETP-transgenic mice by the ectopic egg embryonation. CD36RP is thus a candidate receptor of S. japonicum to facilitate uptake of HDL-CE necessary for egg embryonation. Abnormal HDL caused by CETP-deficiency retards this process and thereby protects the patients from development of hepatic lesions. S. japonicum infection is a potential screening factor for high prevalence of CETP deficiency in East Asia. PMID:24388961

Yokoyama, Shinji

2014-04-01

145

Plasmid-based transient human stromal cell-derived factor-1 gene transfer improves cardiac function in chronic heart failure  

PubMed Central

We previously demonstrated that transient stromal cell-derived factor-1 alpha (SDF-1) improved cardiac function when delivered via cell therapy in ischemic cardiomyopathy at a time remote from acute myocardial infarction (MI) rats. We hypothesized that non-viral gene transfer of naked plasmid DNA-expressing hSDF-1 could similarly improve cardiac function. To optimize plasmid delivery, we tested SDF-1 and luciferase plasmids driven by the cytomegalovirus (CMV) promoter with (pCMVe) or without (pCMV) translational enhancers or ? myosin heavy chain (pMHC) promoter in a rodent model of heart failure. In vivo expression of pCMVe was 10-fold greater than pCMV and pMHC expression and continued over 30 days. We directly injected rat hearts with SDF-1 plasmid 1 month after MI and assessed heart function. At 4 weeks after plasmid injection, we observed a 35.97 and 32.65% decline in fractional shortening (FS) in control (saline) animals and pMHC-hSDF1 animals, respectively, which was sustained to 8 weeks. In contrast, we observed a significant 24.97% increase in animals injected with the pCMVe-hSDF1 vector. Immunohistochemistry of cardiac tissue revealed a significant increase in vessel density in the hSDF-1-treated animals compared with control animals. Increasing SDF-1 expression promoted angiogenesis and improved cardiac function in rats with ischemic heart failure along with evidence of scar remodeling with a trend toward decreased myocardial fibrosis. These data demonstrate that stand-alone non-viral hSDF-1 gene transfer is a strategy for improving cardiac function in ischemic cardiomyopathy. PMID:21472007

Sundararaman, S; Miller, T J; Pastore, J M; Kiedrowski, M; Aras, R; Penn, M S

2011-01-01

146

Assessing student expertise in introductory physics with isomorphic problems. II. Effect of some potential factors on problem solving and transfer  

NSDL National Science Digital Library

This paper explores the use of isomorphic problem pairs (IPPs) to assess introductory physics studentsâ ability to solve and successfully transfer problem-solving knowledge from one context to another in mechanics. The paired problems are âisomorphicâ because they require the same physics principle to solve them. We analyze written responses, individual discussions for a range of isomorphic problems, and potential factors that may help or hinder transfer of problem-solving skills from one problem in a pair to the other. When quantitative and conceptual questions were paired and given back to back, students who answered both questions in the IPP often performed better on the conceptual questions than those who answered the corresponding conceptual questions only. Although students often took advantage of the quantitative counterpart to answer a conceptual question of an IPP correctly, when only given the conceptual question, students seldom tried to convert it into a quantitative question, solve it, and then reason about the solution conceptually. Even in individual interviews when students who were given only conceptual questions had difficulty and the interviewer explicitly encouraged them to convert the conceptual question into the corresponding quantitative problem by choosing appropriate variables, a majority of students were reluctant and preferred to guess the answer to the conceptual question based upon their gut feeling. Misconceptions associated with friction in some problems were so robust that pairing them with isomorphic problems not involving friction did not help students discern their underlying similarities. Alternatively, from the knowledge-in-pieces perspective, the activation of the knowledge resource related to friction was so strongly and automatically triggered by the context, which is outside the conscious control of the student, that students did not look for analogies with paired problems or other aids that may be present.

Singh, Chandralekha

2008-09-24

147

Blocking Single-Stranded Transferred DNA Conversion to Double-Stranded Intermediates by Overexpression of Yeast DNA REPLICATION FACTOR A.  

PubMed

Agrobacterium tumefaciens delivers its single-stranded transferred DNA (T-strand) into the host cell nucleus, where it can be converted into double-stranded molecules. Various studies have revealed that double-stranded transfer DNA (T-DNA) intermediates can serve as substrates by as yet uncharacterized integration machinery. Nevertheless, the possibility that T-strands are themselves substrates for integration cannot be ruled out. We attempted to block the conversion of T-strands into double-stranded intermediates prior to integration in order to further investigate the route taken by T-DNA molecules on their way to integration. Transgenic tobacco (Nicotiana benthamiana) plants that overexpress three yeast (Saccharomyces cerevisiae) protein subunits of DNA REPLICATION FACTOR A (RFA) were produced. In yeast, these subunits (RFA1-RFA3) function as a complex that can bind single-stranded DNA molecules, promoting the repair of genomic double strand breaks. Overexpression of the RFA complex in tobacco resulted in decreased T-DNA expression, as determined by infection with A. tumefaciens cells carrying the ?-glucuronidase intron reporter gene. Gene expression was not blocked when the reporter gene was delivered by microbombardment. Enhanced green fluorescent protein-assisted localization studies indicated that the three-protein complex was predominantly nuclear, thus indicating its function within the plant cell nucleus, possibly by binding naked T-strands and blocking their conversion into double-stranded intermediates. This notion was further supported by the inhibitory effect of RFA expression on the cell-to-cell movement of Bean dwarf mosaic virus, a single-stranded DNA virus. The observation that RFA complex plants dramatically inhibited the transient expression level of T-DNA and only reduced T-DNA integration by 50% suggests that double-stranded T-DNA intermediates, as well as single-stranded T-DNA, play significant roles in the integration process. PMID:25424309

Dafny-Yelin, Mery; Levy, Avner; Dafny, Raz; Tzfira, Tzvi

2015-01-01

148

Effect of the maternofetal and milk transfer of the anti-epidermal growth factor receptor monoclonal antibody 7A7 in mice  

Microsoft Academic Search

ObjectivesTo study the maternofetal and milk transfer of an anti-epidermal growth factor receptor (EGFR) monoclonal antibody (MAb) and its effects on conceptus, we administered to pregnant and lactating dams the murine anti-EGFR MAb 7A7 in an autologus model.

J. E. González; M. León; I. Hernández; G. Garrido; Á. Casacó

2011-01-01

149

Factoring  

NSDL National Science Digital Library

Test your factoring skills Factors and Multiples Jeopardy How much do you know about factoring and multiples? Play Jeopardy and find out! Prime Factoring Turkey Shoot Blast these turkeys using your factoring skills. Help the Professor Super save the planet by "cooking" the Giant Frozen Turkeys of Destruction. Math Lines 12 X-Factor Shoot the ball at the other factors to get a product of 12. You can also ...

Mr Clark

2012-10-31

150

Analysis of linear energy transfers and quality factors of charged particles produced by spontaneous fission neutrons from 252Cf and 244Pu in the human body.  

PubMed

Absorbed doses, linear energy transfers (LETs) and quality factors of secondary charged particles in organs and tissues, generated via the interactions of the spontaneous fission neutrons from (252)Cf and (244)Pu within the human body, were studied using the Particle and Heavy Ion Transport Code System (PHITS) coupled with the ICRP Reference Phantom. Both the absorbed doses and the quality factors in target organs generally decrease with increasing distance from the source organ. The analysis of LET distributions of secondary charged particles led to the identification of the relationship between LET spectra and target-source organ locations. A comparison between human body-averaged mean quality factors and fluence-averaged radiation weighting factors showed that the current numerical conventions for the radiation weighting factors of neutrons, updated in ICRP103, and the quality factors for internal exposure are valid. PMID:22908356

Endo, Akira; Sato, Tatsuhiko

2013-04-01

151

Numerical Investigation of Heat Transfer and Friction Factor Characteristics in a Circular Tube Fitted with V-Cut Twisted Tape Inserts  

PubMed Central

Numerical investigation of the heat transfer and friction factor characteristics of a circular fitted with V-cut twisted tape (VCT) insert with twist ratio (y = 2.93) and different cut depths (w = 0.5, 1, and 1.5?cm) were studied for laminar flow using CFD package (FLUENT-6.3.26). The data obtained from plain tube were verified with the literature correlation to ensure the validation of simulation results. Classical twisted tape (CTT) with different twist ratios (y = 2.93, 3.91, 4.89) were also studied for comparison. The results show that the enhancement of heat transfer rate induced by the classical and V-cut twisted tape inserts increases with the Reynolds number and decreases with twist ratio. The results also revealed that the V-cut twisted tape with twist ratio y = 2.93 and cut depth w = 0.5?cm offered higher heat transfer rate with significant increases in friction factor than other tapes. In addition the results of V-cut twist tape compared with experimental and simulated data of right-left helical tape inserts (RLT), it is found that the V-cut twist tape offered better thermal contact between the surface and the fluid which ultimately leads to a high heat transfer coefficient. Consequently, 107% of maximum heat transfer was obtained by using this configuration. PMID:24078795

Salman, Sami D.; Kadhum, Abdul Amir H.; Takriff, Mohd S.; Mohamad, Abu Bakar

2013-01-01

152

Vascular endothelial growth factor-B gene transfer exacerbates retinal and choroidal neovascularization and vasopermeability without promoting inflammation  

PubMed Central

Purpose The role of vascular endothelial growth factor (VEGF)-B in the eye is poorly understood. The present study was conducted to evaluate the effect of overexpression of VEGF-B via adeno-associated virus (AAV) gene transfer on ocular angiogenesis, inflammation, and the blood-retinal barrier (BRB). Methods Three recombinant AAV vectors were prepared, expressing the 167 (AAV-VEGF-B167) or 186 amino acid isoform (AAV-VEGF-B186) of VEGF-B or the green fluorescent protein (GFP) reporter gene (AAV-GFP). Approximately 1×109 viral genome copies of AAV-VEGF-B167, AAV-VEGF-B186, or AAV-GFP were intraocularly injected. The efficacy of the gene transfer was assessed by directly observing GFP, by immunohistochemistry, or by real-time PCR. A leukostasis assay using fluorescein isothiocyanate-conjugated Concanavalin A was used to evaluate inflammation. The BRB was assessed using a quantitative assay with 3H-mannitol as a tracer. Retinal neovascularization (NV) was assessed at postnatal day 17 in oxygen-induced ischemic retinopathy after intravitreal injection of AAV-VEGF-B in left eyes and AAV-GFP in right eyes at postnatal day 7. Two weeks after injection of AAV vectors, choroidal NV was generated by laser photocoagulation and assessed 2 weeks later. Results GFP expression was clearly demonstrated, primarily in the retinal pigment epithelium (RPE) and outer retina, 1–6 weeks after delivery. mRNA expression levels of VEGF-B167 and VEGF-B186 were 5.8 and 12 fold higher in the AAV-VEGF-B167- and AAV-VEGF-B186-treated groups, respectively. There was no evidence of an inflammatory response or vessel abnormality following injection of the vectors in normal mice; however, VEGF-B increased retinal and choroidal neovascularization. AAV-VEGF-B186, but not AAV-VEGF-B167, enhanced retinal vascular permeability. Conclusions VEGF-B overexpression promoted pathological retinal and choroidal NV and BRB breakdown without causing inflammation, which is associated with the progression of diabetic retinopathy and age-related macular degeneration, showing that these complications are not dependent on inflammation. VEGF-B targeting could benefit antiangiogenic therapy. PMID:21364963

Zhong, Xiufeng; Huang, Hu; Shen, Jikui; Zacchigna, Serena; Zentilin, Lorena; Giacca, Mauro

2011-01-01

153

Molecular Cloning of a Xylosyltransferase That Transfers the Second Xylose to O-Glucosylated Epidermal Growth Factor Repeats of Notch*  

PubMed Central

The extracellular domain of Notch contains epidermal growth factor (EGF) repeats that are extensively modified with different O-linked glycans. O-Fucosylation is essential for receptor function, and elongation with N-acetylglucosamine, catalyzed by members of the Fringe family, modulates Notch activity. Only recently, genes encoding enzymes involved in the O-glucosylation pathway have been cloned. In the Drosophila mutant rumi, characterized by a mutation in the protein O-glucosyltransferase, Notch signaling is impaired in a temperature-dependent manner, and a mouse knock-out leads to embryonic lethality. We have previously identified two human genes, GXYLT1 and GXYLT2, encoding glucoside xylosyltransferases responsible for the transfer of xylose to O-linked glucose. The identity of the enzyme further elongating the glycan to generate the final trisaccharide xylose-xylose-glucose, however, remained unknown. Here, we describe that the human gene C3ORF21 encodes a UDP-xylose:?-xyloside ?1,3-xylosyltransferase, acting on xylose-?1,3-glucose?1-containing acceptor structures. We have, therefore, renamed it XXYLT1 (xyloside xylosyltransferase 1). XXYLT1 cannot act on a synthetic acceptor containing an ?-linked xylose alone, but requires the presence of the underlying glucose. Activity on Notch EGF repeats was proven by in vitro xylosylation of a mouse Notch1 fragment recombinantly produced in Sf9 insect cells, a bacterially expressed EGF repeat from mouse Notch2 modified in vitro by Rumi and Gxylt2 and in vivo by co-expression of the enzyme with the Notch1 fragment. The enzyme was shown to be a typical type II membrane-bound glycosyltransferase localized in the endoplasmic reticulum. PMID:22117070

Sethi, Maya K.; Buettner, Falk F. R.; Ashikov, Angel; Krylov, Vadim B.; Takeuchi, Hideyuki; Nifantiev, Nikolay E.; Haltiwanger, Robert S.; Gerardy-Schahn, Rita; Bakker, Hans

2012-01-01

154

Therapeutic effect of transforming growth factor-beta 2 on actively induced EAN but not adoptive transfer EAN.  

PubMed Central

A possible effect of transforming growth factor type-beta 2 (TGF-beta 2) on autoimmune inflammation of the peripheral nervous system (PNS) was evaluated in experimental autoimmune neuritis (EAN) in Lewis rats, a disease model of the human Guillain-Barré syndrome. First, EAN was actively induced by immunization with a neuritogenic peptide corresponding to amino acids 53-78 of the bovine P2 protein. Intraperitoneal (i.p.) administration of 5 micrograms TGF-beta 2 per day after onset of clinical disease shortened the duration and ameliorated the severity of EAN compared to sham-injected control animals. Inflammatory infiltration and demyelination was significantly reduced in sciatic nerves of TGF-beta-treated animals, although expression of major histocompatibility complex (MHC) class II antigens was not down-regulated. Second, EAN was induced by adoptive transfer (AT) of activated P2-specific T-line cells (AT-EAN). Daily injections of 5 micrograms TGF-beta 2 i.p., beginning on the day of first clinical signs, failed to modify the clinical course of AT-EAN, although the antigen-induced activation of the neuritogenic T-line cells used for induction of disease was found to be partially sensitive to the inhibitory effect of TGF-beta in vitro. The experiments indicate that TGF-beta 2 holds promise as a therapeutic agent to combat autoimmunity in the PNS. They also suggest that the therapeutic efficacy of TGF-beta on rapidly developing disease such as AT-EAN is limited, as with other non-specific immunosuppressive drugs. Images Figure 2 Figure 3 PMID:7533133

Jung, S; Schluesener, H J; Schmidt, B; Fontana, A; Toyka, K V; Hartung, H P

1994-01-01

155

137Cs Inter-Plant Concentration Ratios Provide a Predictive Tool for Coral Atolls with Distinct Benefits Over Transfer Factors  

SciTech Connect

Inter-plant concentration ratios (IPCR), [Bq g{sup -1} {sup 137}Cs in coral atoll tree food-crops/Bq g{sup -1} {sup 137}Cs in leaves of native plant species whose roots share a common soil volume], can replace transfer factors (TF) to predict {sup 137}Cs concentration in tree food-crops in a contaminated area with an aged source term. The IPCR strategy has significant benefits relative to TF strategy for such purposes in the atoll ecosystem. IPCR strategy applied to specific assessments takes advantage of the fact tree roots naturally integrate 137Cs over large volumes of soil. Root absorption of {sup 137}Cs replaces large-scale, expensive soil sampling schemes to reduce variability in {sup 137}Cs concentration due to inhomogeneous radionuclide distribution. IPCR [drinking-coconut meat (DCM)/Scaevola (SCA) and Tournefortia (TOU) leaves (native trees growing on all atoll islands)] are log normally distributed (LND) with geometric standard deviation (GSD) = 1.85. TF for DCM from Enewetak, Eneu, Rongelap and Bikini Atolls are LND with GSD's of 3.5, 3.0, 2.7, and 2.1, respectively. TF GSD for Rongelap copra coconut meat is 2.5. IPCR of Pandanus fruit to SCA and TOU leaves are LND with GSD = 1.7 while TF GSD is 2.1. Because IPCR variability is much lower than TF variability, relative sampling error of an IPCR field sample mean is up 6- to 10-fold lower than that of a TF sample mean if sample sizes are small (10 to 20). Other IPCR advantages are that plant leaf samples are collected and processed in far less time with much less effort and cost than soil samples.

Robison, W L; Hamilton, T F; Bogen, K; Corado, C L; Kehl, S R

2007-07-17

156

In-Hospital Mortality among Rural Medicare Patients with Acute Myocardial Infarction: The Influence of Demographics, Transfer, and Health Factors  

ERIC Educational Resources Information Center

Context/Purpose: Most rural hospitals can provide medical care to acute myocardial infarction (AMI) patients, but a need for advanced cardiac care requires timely transfer to a tertiary hospital. There is little information on AMI in-hospital mortality predictors among rural transfer patients. Methods: Cross-sectional retrospective analyses on…

Muus, Kyle J.; Knudson, Alana D.; Klug, Marilyn G.; Wynne, Joshua

2011-01-01

157

Experimental Analysis of the Single-Phase Heat Transfer and Friction Factor inside the Horizontal Internally Micro-Fin Tube  

E-print Network

of tube is widely used in high flow rate applications because the heat transfer enhancement in high flow rates (turbulent region) is more pronounced than that in the low flow rates (laminar region). Khanpara and shell-side condensers to increase heat transfer. This enables water chillers to reach high efficiency

Ghajar, Afshin J.

158

Robotic technology evolution and transfer  

NASA Technical Reports Server (NTRS)

A report concerning technology transfer in the area of robotics is presented in vugraph form. The following topics are discussed: definition of technology innovation and tech-transfer; concepts relevant for understanding tech-transfer; models advanced to portray tech-transfer process; factors identified as promoting tech-transfer; factors identified as impeding tech-transfer; what important roles do individuals fulfill in tech-transfer; federal infrastructure for promoting tech-transfer; federal infrastructure for promoting tech-transfer; robotic technology evolution; robotic technology transferred; and recommendations for successful robotics tech-transfer.

Marzwell, Neville I.

1992-01-01

159

Soil-to-soybean transfer of (99)Tc and its underground distribution in differently contaminated upland soils.  

PubMed

Pot experiments were performed in a greenhouse to investigate the soil-to-soybean transfer of (99)Tc in two different upland soils labeled with (99)TcO4(-) in two contrasting ways. One was to mix the soil with a (99)TcO4(-) solution 26 d before sowing (pre-sowing deposition: PSD), and the other was to apply the solution onto the soil surface 44 d after sowing (growing-period deposition: GPD). The soil-to-plant transfer was quantified with the transfer factor (TF, ratio of the plant concentration to the average of at-planting and at-harvest soil concentrations) or the aggregated transfer factor (TFag, ratio of the plant concentration to the deposition density). For both the depositions, the transfer of (99)Tc to aerial parts decreased in the order of leaf > stem > pod > seed. TF values (dimensionless) from the PSD were 0.22 and 0.27 (no statistically significant difference) for mature dry seeds in the respective soils, whereas a 600-fold higher value occurred for dry leaves. The post-harvest concentrations of the PSD (99)Tc in the top 20 cm soils as a whole were about half the initial concentrations. Around 25% of the total applied activity remained in the GPD soils after the harvest. The post-harvest depth profiles of the GPD (99)Tc in the two soils showed similar patterns of logarithmic activity decrease with increasing soil depths. Only 1.5-4.3% of the total applied activity was removed through the harvested biomass (seeds, pods and stems), and it was estimated that a great part of the total pant uptake returned to the soil through the fallen leaves. TFag values (m(2) kg(-1)) were about 2-4 times higher for the GPD than for the PSD. This finding and generally high root uptake of Tc may indicate that the use of empirical deposition time-dependent TFag data is particularly important for predicting the plant concentrations of Tc after its growing-period deposition. PMID:24556176

Choi, Yong-Ho; Lim, Kwang-Muk; Jun, In; Kim, Byung-Ho; Keum, Dong-Kwon; Kim, In-Gyu

2014-06-01

160

Factors influencing the efficiency of generating genetically engineered pigs by nuclear transfer: multi-factorial analysis of a large data set  

PubMed Central

Background Somatic cell nuclear transfer (SCNT) using genetically engineered donor cells is currently the most widely used strategy to generate tailored pig models for biomedical research. Although this approach facilitates a similar spectrum of genetic modifications as in rodent models, the outcome in terms of live cloned piglets is quite variable. In this study, we aimed at a comprehensive analysis of environmental and experimental factors that are substantially influencing the efficiency of generating genetically engineered pigs. Based on a considerably large data set from 274 SCNT experiments (in total 18,649 reconstructed embryos transferred into 193 recipients), performed over a period of three years, we assessed the relative contribution of season, type of genetic modification, donor cell source, number of cloning rounds, and pre-selection of cloned embryos for early development to the cloning efficiency. Results 109 (56%) recipients became pregnant and 85 (78%) of them gave birth to offspring. Out of 318 cloned piglets, 243 (76%) were alive, but only 97 (40%) were clinically healthy and showed normal development. The proportion of stillborn piglets was 24% (75/318), and another 31% (100/318) of the cloned piglets died soon after birth. The overall cloning efficiency, defined as the number of offspring born per SCNT embryos transferred, including only recipients that delivered, was 3.95%. SCNT experiments performed during winter using fetal fibroblasts or kidney cells after additive gene transfer resulted in the highest number of live and healthy offspring, while two or more rounds of cloning and nuclear transfer experiments performed during summer decreased the number of healthy offspring. Conclusion Although the effects of individual factors may be different between various laboratories, our results and analysis strategy will help to identify and optimize the factors, which are most critical to cloning success in programs aiming at the generation of genetically engineered pig models. PMID:23688045

2013-01-01

161

Astrophysical S factor for the radiative capture 12N(p,gamma)13O determined from the 14N(12N,13O)13C proton transfer reaction  

E-print Network

The cross section of the radiative proton capture reaction on the drip line nucleus 12N was investigated using the Asymptotic Normalization Coefficient (ANC) method. We have used the 14N(12N,13O)13C proton transfer reaction at 12 MeV/nucleon to extract the ANC for 13O -> 12N + p and calculate from it the direct component of the astrophysical S factor of the 12N(p,gamma)13O reaction. The optical potentials used and the DWBA analysis of the proton transfer reaction are discussed. For the entrance channel, the optical potential was inferred from an elastic scattering measurement carried out at the same time with the transfer measurement. From the transfer, we determined the square of the ANC, C^2(13Og.s.) = 2.53 +/- 0.30 fm-1, and hence a value of 0.33(4) keVb was obtained for the direct astrophysical S factor at zero energy. Constructive interference at low energies between the direct and resonant captures leads to an enhancement of Stotal(0) = 0.42(5) keVb. The 12N(p,gamma)13O reaction was investigated in relation to the evolution of hydrogen-rich massive Population III stars, for the role that it may play in the hot pp-chain nuclear burning processes, possibly occurring in such objects.

A. Banu; T. Al-Abdullah; C. Fu; C. A. Gagliardi; M. McCleskey; A. M. Mukhamedzhanov; G. Tabacaru; L. Trache; R. E. Tribble; Y. Zhai; F. Carstoiu; V. Burjan; V. Kroha

2008-10-31

162

Probing the rate-limiting step for intramolecular transfer of a transcription factor between specific sites on the same DNA molecule by (15)Nz-exchange NMR spectroscopy.  

PubMed

The kinetics of translocation of the homeodomain transcription factor HoxD9 between specific sites of the same or opposite polarities on the same DNA molecule have been studied by (15)Nz-exchange NMR spectroscopy. We show that exchange occurs by two facilitated diffusion mechanisms: a second-order intermolecular exchange reaction between specific sites located on different DNA molecules without the protein dissociating into free solution that predominates at high concentrations of free DNA, and a first-order intramolecular process involving direct transfer between specific sites located on the same DNA molecule. Control experiments using a mixture of two DNA molecules, each possessing only a single specific site, indicate that transfer between specific sites by full dissociation of HoxD9 into solution followed by reassociation is too slow to measure by z-exchange spectroscopy. Intramolecular transfer with comparable rate constants occurs between sites of the same and opposing polarity, indicating that both rotation-coupled sliding and hopping/flipping (analogous to geminate recombination) occur. The half-life for intramolecular transfer (0.5-1 s) is many orders of magnitude larger than the calculated transfer time (1-100 ?s) by sliding, leading us to conclude that the intramolecular transfer rates measured by z-exchange spectroscopy represent the rate-limiting step for a one-base-pair shift from the specific site to the immediately adjacent nonspecific site. At zero concentration of added salt, the intramolecular transfer rate constants between sites of opposing polarity are smaller than those between sites of the same polarity, suggesting that hopping/flipping may become rate-limiting at very low salt concentrations. PMID:25253516

Ryu, Kyoung-Seok; Tugarinov, Vitali; Clore, G Marius

2014-10-15

163

A Measurement of the neutron electric form factor at very large momentum transfer using polaried electrions scattering from a polarized helium-3 target  

SciTech Connect

Knowledge of the electric and magnetic elastic form factors of the nucleon is essential for an understanding of nucleon structure. Of the form factors, the electric form factor of the neutron has been measured over the smallest range in Q{sup 2} and with the lowest precision. Jefferson Lab experiment 02-013 used a novel new polarized {sup 3}He target to nearly double the range of momentum transfer in which the neutron form factor has been studied and to measure it with much higher precision. Polarized electrons were scattered off this target, and both the scattered electron and neutron were detected. G{sup n}{sub E} was measured to be 0.0242 ± 0.0020(stat) ± 0.0061(sys) and 0.0247 ± 0.0029(stat) ± 0.0031(sys) at Q{sup 2} = 1.7 and 2.5 GeV{sup 2}, respectively.

Aidan Kelleher

2010-10-01

164

Factorize  

NSDL National Science Digital Library

This interactive applet allows a student to visually explore the concept of factors by creating different rectangular arrays for a number. The user constructs the array by clicking and dragging on a grid. The length and width of the array are factors of the number. A student can elect an option of a randomly selected number or the student selects his own number between 2 and 50. Exploration questions are included to promote student discovery of mathematical concepts with factors.

2000-01-01

165

Effect of nitrogen, potassium and humic acid on ( 134 )Cs transfer factors to wheat from tropical soils in Neubauer growth units.  

PubMed

A Neubauer plantlet experiment was carried out using Inceptisol (Typic Haplustept) and Vertisol (Typic Chromustert) soils contaminated with 134Cs at 74 kBq kg(-1) soil to study the transfer factor to wheat crop (Triticum aestivum) as influenced by four levels of humic acid (100, 200, 300, 400 mg HA kg(-1) soil), potassium and NH4-N (36.4, 54.5, 72.7 and 90.9 mg K or NH4 kg(-1) soil) under tropical climate. The biomass yield and K uptake by wheat were significantly improved in Vertisol with NH4-N and K application. The potassium application significantly increased the potassium concentration in wheat plants. The increase in the levels of each of the treatments dramatically improved the yield, K content and K uptake parameters, irrespective of the soils. The 134Cs transfer factors, irrespective of the treatments were observed to be higher in Vertisols as compared to Inceptisols. Among the treatments, the effect of HA was significantly greater than that of K and NH4-N application in Inceptisol, however, in Vertisols both HA and NH4-N were observed to be superior as compared to K application. With each increment in the levels of the treatments, a significantly lowered TF value was found, higher in Inceptisols (56.3%) than Vertisols (48.5%). Comparison of treatments indicates that in general higher potassium concentration in plant drastically lowered radiocesium transfer to wheat. Neubauer plant culture study, a rapid laboratory experimental model based on simple soil-plant system was quite clearly brought out the potential effectiveness of N, K and HA on soil-to-wheat transfer of radiocesium. Such screening technique needs to be extended to cover wider crop species, different climatic conditions and factors governing/modifying the mobility of radiocesium in soil and its absorption by crop plants. PMID:18259886

Sandeep, S; Manjaiah, K M; Sachdev, P; Sachdev, M S

2009-02-01

166

Antitumor effect of nuclear factor-?B decoy transfer by mannose-modified bubble lipoplex into macrophages in mouse malignant ascites.  

PubMed

Patients with malignant ascites (MAs) display several symptoms, such as dyspnea, nausea, pain, and abdominal tenderness, resulting in a significant reduction in their quality of life. Tumor-associated macrophages (TAMs) play a crucial role in MA progression. Because TAMs have a tumor-promoting M2 phenotype, conversion of the M2 phenotypic function of TAMs would be promising for MA treatment. Nuclear factor-?B (NF-?B) is a master regulator of macrophage polarization. Here, we developed targeted transfer of a NF-?B decoy into TAMs by ultrasound (US)-responsive, mannose-modified liposome/NF-?B decoy complexes (Man-PEG bubble lipoplexes) in a mouse peritoneal dissemination model of Ehrlich ascites carcinoma. In addition, we investigated the effects of NF-?B decoy transfection into TAMs on MA progression and mouse survival rates. Intraperitoneal injection of Man-PEG bubble lipoplexes and US exposure transferred the NF-?B decoy into TAMs effectively. When the NF-?B decoy was delivered into TAMs by this method in the mouse peritoneal dissemination model, mRNA expression of the Th2 cytokine interleukin (IL)-10 in TAMs was decreased significantly. In contrast, mRNA levels of Th1 cytokines (IL-12, tumor necrosis factor-?, and IL-6) were increased significantly. Moreover, the expression level of vascular endothelial growth factor in ascites was suppressed significantly, and peritoneal angiogenesis showed a reduction. Furthermore, NF-?B decoy transfer into TAMs significantly decreased the ascitic volume and number of Ehrlich ascites carcinoma cells in ascites, and prolonged mouse survival. In conclusion, we transferred a NF-?B decoy efficiently by Man-PEG bubble lipoplexes with US exposure into TAMs, which may be a novel approach for MA treatment. PMID:24850474

Kono, Yusuke; Kawakami, Shigeru; Higuchi, Yuriko; Maruyama, Kazuo; Yamashita, Fumiyoshi; Hashida, Mitsuru

2014-08-01

167

Study of complement regulatory factor H based on Forster resonance energy transfer and investigation of disease-linked genetic variants   

E-print Network

The plasma protein complement factor H (fH, 155 kDa) regulates the activity of the alternative pathway of complement activation. Factor H is monomeric, and its 20 CCP modules are arranged in a predominantly elongated ...

Pechtl, Isabell C.

2010-01-01

168

Bacteroides fragilis Transfer Factor Tn5520: the Smallest Bacterial Mobilizable Transposon Containing Single Integrase and Mobilization Genes That Function in Escherichia coli  

PubMed Central

Many bacterial genera, including Bacteroides spp., harbor mobilizable transposons, a class of transfer factors that carry genes for conjugal DNA transfer and, in some cases, antibiotic resistance. Mobilizable transposons are capable of inserting into and mobilizing other, nontransferable plasmids and are implicated in the dissemination of antibiotic resistance. This paper presents the isolation and characterization of Tn5520, a new mobilizable transposon from Bacteroides fragilis LV23. At 4,692 bp, it is the smallest mobilizable transposon reported from any bacterial genus. Tn5520 was captured from B. fragilis LV23 by using the transfer-deficient shuttle vector pGAT400?BglII. The termini of Tn5520 contain a 22-bp imperfect inverted repeat, and transposition does not result in a target site repeat. Tn5520 also demonstrates insertion site sequence preferences characterized by A-T-rich nucleotide sequences. Tn5520 has been sequenced in its entirety, and two large open reading frames whose predicted protein products exhibit strong sequence similarity to recombinase-integrase enzymes and mobilization proteins, respectively, have been identified. The transfer, mobilization, and transposition properties of Tn5520 have been studied, revealing that Tn5520 mobilizes plasmids in both B. fragilis and Escherichia coli at high frequency and also transposes in E. coli. PMID:10198023

Vedantam, Gayatri; Novicki, Thomas J.; Hecht, David W.

1999-01-01

169

Examining Factors Affecting Beginning Teachers' Transfer of Learning of ICT-Enhanced Learning Activities in Their Teaching Practice  

ERIC Educational Resources Information Center

This study examined 100 beginning teachers' transfer of learning when utilising Information Communication Technology-enhanced activity-based learning activities. The beginning teachers had participated in a professional development program that was characterised by "learning technology by collaborative design" in their final year of…

Agyei, Douglas D.; Voogt, Joke

2014-01-01

170

Electronic and nuclear factors in intramolecular charge and excitation transfer processes. [Annual report], October 1992--September 1993  

SciTech Connect

A qualitative discussion is given of initial work on the following topics: intramolecular triplet excitation transfer bands, donor-- bridge--acceptor systems with a tethered ion, and depolarization of transient microwave conductivity. A number of special compounds were synthesized, such as spiranes, 2,6-diamino-dihydroanthracene precursor, and para-amino-nitro-biphenyl and -terphenyl.

Piotrowiak, P.

1993-12-31

171

Electronic and nuclear factors in intramolecular charge and excitation transfer processes. [Annual report], October 1992September 1993  

Microsoft Academic Search

A qualitative discussion is given of initial work on the following topics: intramolecular triplet excitation transfer bands, donor-- bridge--acceptor systems with a tethered ion, and depolarization of transient microwave conductivity. A number of special compounds were synthesized, such as spiranes, 2,6-diamino-dihydroanthracene precursor, and para-amino-nitro-biphenyl and -terphenyl.

Piotrowiak

1993-01-01

172

Heat and Mass Transfer in a Reforming Catalyst Bed: Quantitative Evaluation of the Controlling Factor by Experiment  

NASA Astrophysics Data System (ADS)

Heat and mass transfer characteristics in a reforming catalyst bed have been experimentally investigated. Experiments were carried out with a single bench-scaled reforming tube which was filled with reforming catalyst. The tube wall was uniformly heated, and mixtures of steam and methane or propane were reformed through the catalyst bed. Most part of the reaction was completed in the upper part of the test tube. The effects of space velocity, which is a ratio of volumetric flow rate of process gas to the catalyst volume, steam carbon molar ratio, wall temperature, bed temperature, and catalyst particle diameter on the transport phenomena with chemical reaction, were determined. A correlation to heat transfer coefficient was determined by Nu, Rep, Pr, dp/d, and Da. The prediction of the overall methane conversion rate was also presented.

Usami, Yutaka; Fukusako, Shoichiro; Yamada, Masahiko

173

Heat transfer coefficient and friction factor correlations for the transitional flow regime in rib-roughened rectangular ducts  

Microsoft Academic Search

This paper presents results of an experimental investigation of heat transfer and friction for the flow of air in rectangular ducts with repeated chamfered rib-roughness on one broad wall. The aspect ratios of the rectangular duct investigated are 4.8, 6.1, 7.8, 9.66 and 12.0. The roughened wall is uniformly heated while the remaining three walls are insulated. These boundary conditions

R. Karwa; S. C. Solanki; J. S. Saini

1999-01-01

174

Adoptive Transfer of Heme Oxygenase-1 (HO-1)–Modified Macrophages Rescues the Nuclear Factor Erythroid 2–Related Factor (Nrf2) Antiinflammatory Phenotype in Liver Ischemia/Reperfusion Injury  

PubMed Central

Macrophages are instrumental in the pathophysiology of liver ischemia/reperfusion injury (IRI). Although Nrf2 regulates macrophage-specific heme oxygenase-1 (HO-1) antioxidant defense, it remains unknown whether HO-1 induction might rescue macrophage Nrf2-dependent antiinflammatory functions. This study explores the mechanisms by which the Nrf2–HO-1 axis regulates sterile hepatic inflammation responses after adoptive transfer of ex vivo modified HO-1 overexpressing bone marrow–derived macrophages (BMMs). Livers in Nrf2-deficient mice preconditioned with Ad-HO-1 BMMs, but not Ad-?-Gal-BMMs, ameliorated liver IRI (at 6 h of reperfusion after 90 min of warm ischemia), evidenced by improved hepatocellular function (serum alanine aminotransferase [sALT] levels) and preserved hepatic architecture (Suzuki histological score). Treatment with Ad-HO-1 BMMs decreased neutrophil accumulation, proinflammatory mediators and hepatocellular necrosis/apoptosis in ischemic livers. Moreover, Ad-HO-1 transfection of Nrf2-deficient BMMs suppressed M1 (Nos2+) while promoting the M2 (Mrc-1/Arg-1+) phenotype. Unlike in controls, Ad-HO-1 BMMs increased the expression of Notch1, Hes1, phosphorylation of Stat3 and Akt in IR-stressed Nrf2-deficient livers as well as in lipopolysaccharide (LPS)-stimulated BMMs. Thus, adoptive transfer of ex vivo generated Ad-HO-1 BMMs rescued Nrf2-dependent antiinflammatory phenotype by promoting Notch1/Hes1/Stat3 signaling and reprogramming macrophages toward the M2 phenotype. These findings provide the rationale for a novel clinically attractive strategy to manage IR liver inflammation/damage. PMID:25014792

Huang, Jing; Shen, Xiu-Da; Yue, Shi; Zhu, Jianjun; Gao, Feng; Zhai, Yuan; Busuttil, Ronald W; Ke, Bibo; Kupiec-Weglinski, Jerzy W

2014-01-01

175

Experimental determination of average turbulent heat transfer and friction factor in stator internal rib-roughened cooling channels.  

PubMed

In gas turbine cooling design, techniques for heat extraction from the surfaces exposed to the hot stream are based on the increase of the inner heat transfer areas and on the promotion of the turbulence of the cooling flow. This is currently obtained by casting periodic ribs on one or more sides of the serpentine passages into the core of the blade. Fluid dynamic and thermal behaviour of the cooling flow have been extensively investigated by means of experimental facilities and many papers dealing with this subject have appeared in the latest years. The evaluation of the average value of the heat transfer coefficient most of the time is inferred from local measurements obtained by various experimental techniques. Moreover the great majority of these studies are not concerned with the overall average heat transfer coefficient for the combined ribs and region between them, but do focus just on one of them. This paper presents an attempt to collect information about the average Nusselt number inside a straight ribbed duct. Series of measurements have been performed in steady state eliminating the error sources inherently connected with transient methods. A low speed wind tunnel, operating in steady state flow, has been built to simulate the actual flow condition occurring in a rectilinear blade cooling channel. A straight square channel with 20 transverse ribs on two sides has been tested for Re of about 3 x 10(4), 4.5 x 10(4) and 6 x 10(4). The ribbed wall test section is electrically heated and the heat removed by a stationary flow of known thermal and fluid dynamic characteristics. PMID:11460662

Battisti, L; Baggio, P

2001-05-01

176

First measurement of the electromagnetic form factor of the neutral kaon at a large momentum transfer and the effect of SU(3) breaking  

NASA Astrophysics Data System (ADS)

At large momentum transfers the photon interacts with the charges and spins of the constituent partons in a hadron. It is expected that the neutral kaon can acquire finite electromagnetic form factors because its wave function is affected by the order of magnitude difference between the mass of the strange quark and that of the down quark, or flavor SU(3) breaking. We report on the first measurement of the form factor of neutral kaons at the large timelike momentum transfer of |Q2|=17.4 GeV by measuring the cross section for e+e-?KSKL at ?{s}=4.17 GeV using CLEO-c data with an integrated luminosity of 586 pb-1. We obtain F(17.4 GeV)=5.3×10-3, with a 90% C.L. interval of (2.9-8.2)×10-3. This is nearly an order of magnitude smaller than F(17.4 GeV)=(44±1)×10-3, and indicates that the effect of SU(3) breaking is small. In turn, this makes it unlikely that the recently observed strong violation of the pQCD prediction, F(|Q2|)/F(|Q2|)=f?2/fK2, which is based on the assumption of similar wave functions for the pions and kaons, can be attributed to SU(3) breaking alone.

Seth, Kamal K.; Dobbs, S.; Tomaradze, A.; Xiao, T.; Bonvicini, G.

2014-03-01

177

Transfer of Learning.  

ERIC Educational Resources Information Center

This document contains four papers from a symposium on transfer of learning. "Factors Affecting Transfer of Training in an Industrial Setting" (Reid A. Bates, Elwood F. Holton III, Dian L. Seyler) identified seven transfer climate variables that predicted performance and three interpersonal variables that predicted performance ratings. Results…

1997

178

Transfer of Learning. Symposium.  

ERIC Educational Resources Information Center

This document contains three papers on transfer of training and human resources. "The Effect of Organizational Support, Management Support, and Peer Support on Transfer of Training" (Susan E. Cromwell, Judith A. Kolb) reports on a longitudinal study of work environment factors that affect transfer of training in a university supervisory skills…

2002

179

Improving plant drought, salt, and freezing tolerance by gene transfer of a single stress-inducible transcription factor  

Microsoft Academic Search

Plant productivity is greatly affected by environmental stresses such as drought, salt loading, and freezing. We reported previously that a cis -acting promoter element, the dehydration response element (DRE), plays an important role in regulating gene expression in response to these stresses. The transcription factor DREB1A specifically interacts with the DRE and induces expression of stress tolerance genes. We show

Mie Kasuga; Qiang Liu; Setsuko Miura; Kazuo Shinozaki; Kazuko Yamaguchi-Shinozaki

1999-01-01

180

Assessment of selenium food chain transfer and critical exposure factors for avian wildlife species: Need for site-specific data  

SciTech Connect

Observations of selenium poisoning in Belews Lake, NC in the mid-1970s and Kesterson Reservoir, CA in the mid-1980s precipitated a large number of selenium studies. Numerous authors have evaluated the potential for selenium to cause ecologically significant effects via food chain transfer in aquatic ecosystems, especially wetlands. Additionally, bioaccumulation models have been proposed for estimating selenium concentrations in food chains and water that should not be exceeded in order to avoid reproductive effects in avian and aquatic species. The current national chronic ambient water quality criterion (WQC) for protection of aquatic life is 5 {micro}g/L. Scientists with the US Fish and Wildlife Service have recommended setting the ambient water quality criterion at 2 {micro}g/L for both aquatic and wildlife protection.

Adams, W.J. [Kennecott Utah Copper, Magna, UT (United States); Brix, K.V.; Cothern, K.A.; Tear, L.M.; Cardwell, R.D.; Toll, J.E. [Parametrix, Inc., Kirkland, WA (United States); Fairbrother, A. [Ecological Planning and Toxicology, Inc., Corvallis, OR (United States)

1998-12-31

181

Factors determining specificity of signal transduction by G-protein-coupled receptors. Regulation of signal transfer from receptor to G-protein.  

PubMed

Among subfamilies of G-protein-coupled receptors, agonists initiate several cell signaling events depending on the receptor subtype (R) and the type of G-protein (G) or effector molecule (E) expressed in a particular cell. Determinants of signaling specificity/efficiency may operate at the R-G interface, where events are influenced by cell architecture or accessory proteins found in the receptor's microenvironment. This issue was addressed by characterizing signal transfer from R to G following stable expression of the alpha 2A/D adrenergic receptor in two different membrane environments (NIH-3T3 fibroblasts and the pheochromocytoma cell line, PC-12). Receptor coupling to endogenous G-proteins in both cell types was eliminated by pertussis toxin pretreatment and R-G signal transfer restored by reconstitution of cell membranes with purified brain G-protein. Thus, the receptor has access to the same population of G-proteins in the two different environments. In this signal restoration assay, agonist-induced activation of G was 3-9-fold greater in PC-12 as compared with NIH-3T3 alpha 2-adrenergic receptor transfectants. The cell-specific differences in signal transfer were observed over a range of receptor densities or G-protein concentration. The augmented signal transfer in PC-12 versus NIH-3T3 transfectants occurred despite a 2-3-fold lower level of receptors existing in the R-G-coupled state (high affinity, guanyl-5'-yl imidodiphosphate-sensitive agonist binding), suggesting the existence of other membrane factors that influence the nucleotide binding behavior of G-protein in the two cell types. Detergent extraction of PC-12 but not NIH-3T3 membranes yielded a heat-sensitive, macromolecular entity that increased 35S-labeled guanosine 5'-O-(thiotriphosphate) binding to brain G-protein in a concentration-dependent manner. These data indicate that the transfer of signal from R to G is regulated by a cell type-specific, membrane-associated protein that enhances the agonist-induced activation of G. PMID:7797513

Sato, M; Kataoka, R; Dingus, J; Wilcox, M; Hildebrandt, J D; Lanier, S M

1995-06-23

182

Therapeutic Angiogenesis Following Arterial Gene Transfer of Vascular Endothelial Growth Factor in a Rabbit Model of Hindlimb Ischemia  

Microsoft Academic Search

The plasmid phVEGF165, expressing the 165-amino-acid isoform of vascular endothelial growth factor (VEGF), an endothelial cell specific mitogen, was applied to the polymer coating of an angioplasty balloon and delivered percutaneously to the iliac artery of rabbits in which the femoral artery had been excised to cause hindlimb ischemia. Site-specific transfection of phVEGF165resulted in augmented development of collateral vessels documented

Satoshi Takeshita; Lawrence Weir; Dongfen Chen; Lu P. Zheng; Reimer Riessen; Christophe Bauters; James F. Symes; Napoleone Ferrara; Jeffrey M. Isner

1996-01-01

183

Transfer form  

Cancer.gov

10/02 Transfer Investigational Agent Form This form is to be used for an intra-institutional transfer, one transfer/form. Division of Cancer Prevention National Cancer Institute National Institutes of Health TRANSFER FROM: Investigator transferring agent:

184

Improved measurement of labile proton concentration-weighted chemical exchange rate (kws) with experimental factor-compensated and T1-normalized quantitative chemical exchange saturation transfer (CEST) MRI  

PubMed Central

Chemical exchange saturation transfer (CEST) MRI enables measurement of dilute CEST agents and microenvironment properties such as pH and temperature, holding great promise for in vivo applications. However, because of confounding concomitant RF irradiation and relaxation effects, the CEST-weighted MRI contrast may not fully characterize the underlying CEST phenomenon. We postulated that the accuracy of quantitative CEST MRI could be improved if the experimental factors (labeling efficiency and RF spillover effect) were estimated and taken into account. Specifically, the experimental factor was evaluated as a function of exchange rate and CEST agent concentration ratio, which remained relatively constant for intermediate RF irradiation power levels. Hence, the experimental factors can be calculated based on the reasonably estimated exchange rate and labile proton concentration ratio, which significantly improved quantification. The simulation was confirmed with Creatine phantoms of serially varied concentration titrated to the same pH, whose reverse exchange rate (kws) was found to be linearly correlated with the concentration. In summary, the proposed solution provides simplified yet reasonably accurate quantification of the underlying CEST system, which may help guide the ongoing development of quantitative CEST MRI. PMID:22649044

Wu, Renhua; Liu, Charng-Ming; Liu, Philip K; Sun, Phillip Zhe

2012-01-01

185

Metals in benthic macrofauna and biogeochemical factors affecting their trophic transfer to wild fish around fish farm cages.  

PubMed

Benthic macroinvertebrates and wild fish aggregating in the vicinity of four Mediterranean fish farms were sampled. Concentrations of metals and other elements were measured in macrofaunal taxa and in fish tissues (muscle, liver, gills, bone, gonad, stomach, intestine, and stomach content). Biological and geochemical characteristics play an important role in metal accumulation in benthic invertebrates, and consequently in metal transfer to higher trophic levels. Macroinvertebrates accumulated lower concentrations of most metals and elements than their respective sediment, except As, P, Na, Zn and Cd. Elemental concentrations of benthic organisms increased with increasing sediment metal content, except Cd, and with % silt, refractory organic matter and chlorophyll-a of sediment due to the influence of sediment geochemistry on metal bioavailability. Tolerant species were found to accumulate higher concentrations of most metals and elements, except for Cd, than equilibrium species. The ecological and morphological characteristics of the benthic invertebrates can affect the bioaccumulation of metals and elements in macrobenthos. Hg and P were found to increase their concentrations from zoobenthos to wild fish aggregating around fish cages feeding on macrofauna. PMID:24184551

Kalantzi, I; Papageorgiou, N; Sevastou, K; Black, K D; Pergantis, S A; Karakassis, I

2014-02-01

186

Proton spectroscopic factor of the 12C ground state from the 12C (11B,12C) 11B elastic transfer reaction  

NASA Astrophysics Data System (ADS)

The angular distributions of the 12C (11B,11B) 12C and 12C (11B,12C) 11B reactions have been measured at an incident energy of 50 MeV by using the high resolution Q3D magnetic spectrometer of the HI-13 tandem accelerator at China Institute of Atomic Energy, Beijing. The optical potential parameters of the 11B +12C system are determined by fitting the angular distribution of the elastic scattering and then used to predict the cross sections of the elastic transfer reaction leading to the ground state in 12C based on distorted-wave Born approximation (DWBA) analysis. Taking into account the interference between the elastic scattering and the elastic transfer processes, the proton spectroscopic factor of the 12C ground state is extracted to be 2.15 ± 0.23 by constraining the geometrical parameters r0 and a using the rms radius of the valence proton in the 12C ground state.

Li, E. T.; Li, Z. H.; Li, Y. J.; Guo, B.; Wang, Y. B.; Pang, D. Y.; Su, J.; Yan, S. Q.; Zeng, S.; Gan, L.; Li, Z. C.; Liu, J. C.; Bai, X. X.; Wu, Z. D.; Jin, S. J.; Zhang, L. Y.; Yu, X. Q.; Li, L.; Sun, H. B.; Lian, G.; Fan, Q. W.; Liu, W. P.

2014-12-01

187

The vibrational spectra of (CH 3) 3SiX (S = H, F, Br) molecules, revisited . Transferable scale factor sets for methylsilane derivatives  

NASA Astrophysics Data System (ADS)

The joint experimental and theoretical study of the vibrational spectra of the molecular series (CH 3) 3SiX (with X = H, F and Br) is carried out. Data from newly recorded IR and Raman spectra for the bromo derivative, experimental data obtained previously for the remaining species, DFT theoretical calculations and the use of the SQMFF procedure have allowed us to propose common patterns and to unify criteria in their assignment. In addition, two sets of averaged scale factors for the B3LYP force field obtained with two different basis sets (6-31G* and DZP + diff) have been proposed for the common bulky moiety of that molecular series. These parameters were used successfully in order to reproduce the frequency of the bands assigned to the (CH 3) 3Si- group in the vibrational spectra of the corresponding silanolic and methoxy derivatives, i.e., trimethylsilanol and methoxytrimethylsilane, proving their transferability.

Montejo, M.; Ureña, F. Partal; Márquez, F.; González, J. J. López

2005-12-01

188

The vibrational spectra of (CH3)3SiX (S=H, F, Br) molecules, revisited Transferable scale factor sets for methylsilane derivatives.  

PubMed

The joint experimental and theoretical study of the vibrational spectra of the molecular series (CH3)3SiX (with X=H, F and Br) is carried out. Data from newly recorded IR and Raman spectra for the bromo derivative, experimental data obtained previously for the remaining species, DFT theoretical calculations and the use of the SQMFF procedure have allowed us to propose common patterns and to unify criteria in their assignment. In addition, two sets of averaged scale factors for the B3LYP force field obtained with two different basis sets (6-31G* and DZP+diff) have been proposed for the common bulky moiety of that molecular series. These parameters were used successfully in order to reproduce the frequency of the bands assigned to the (CH3)3Si- group in the vibrational spectra of the corresponding silanolic and methoxy derivatives, i.e., trimethylsilanol and methoxytrimethylsilane, proving their transferability. PMID:15967707

Montejo, M; Ureña, F Partal; Márquez, F; González, J J López

2005-12-01

189

Accelerated adhesion of grafted skin by laser-induced stress wave-based gene transfer of hepatocyte growth factor  

NASA Astrophysics Data System (ADS)

Gene therapy using wound healing-associated growth factor gene has received much attention as a new strategy for improving the outcome of tissue transplantation. We delivered plasmid DNA coding for human hepatocyte growth factor (hHGF) to rat free skin grafts by the use of laser-induced stress waves (LISWs); autografting was performed with the grafts. Systematic analysis was conducted to evaluate the adhesion properties of the grafted tissue; angiogenesis, cell proliferation, and reepithelialization were assessed by immunohistochemistry, and reperfusion was measured by laser Doppler imaging as a function of time after grafting. Both the level of angiogenesis on day 3 after grafting and the increased ratio of blood flow on day 4 to that on day 3 were significantly higher than those in five control groups: grafting with hHGF gene injection alone, grafting with control plasmid vector injection alone, grafting with LISW application alone, grafting with LISW application after control plasmid vector injection, and normal grafting. Reepithelialization was almost completed on day 7 even at the center of the graft with LISW application after hHGF gene injection, while it was not for the grafts of the five control groups. These findings demonstrate the validity of our LISW-based HGF gene transfection to accelerate the adhesion of grafted skins.

Aizawa, Kazuya; Sato, Shunichi; Terakawa, Mitsuhiro; Saitoh, Daizoh; Tsuda, Hitoshi; Ashida, Hiroshi; Obara, Minoru

2009-11-01

190

Estimation of heat transfer coefficient and friction factor in the transition flow with low volume concentration of Al 2O 3 nanofluid flowing in a circular tube and with twisted tape insert  

Microsoft Academic Search

Experiments to evaluate heat transfer coefficient and friction factor for flow in a tube and with twisted tape inserts in the transition range of flow with Al2O3 nanofluid are conducted. The results showed considerable enhancement of convective heat transfer with Al2O3 nanofluids compared to flow with water. It is observed that the equation of Gleninski applicable in transitional flow range

K. V. Sharma; L. Syam Sundar; P. K. Sarma

2009-01-01

191

Sites involved in intra- and interdomain allostery associated with the activation of factor viia pinpointed by hydrogen-deuterium exchange and electron transfer dissociation mass spectrometry.  

PubMed

Factor VIIa (FVIIa) is a trypsin-like protease that plays an important role in initiating blood coagulation. Very limited structural information is available for the free, inactive form of FVIIa that circulates in the blood prior to vascular injury and the molecular details of its activity enhancement remain elusive. Here we have applied hydrogen/deuterium exchange mass spectrometry coupled to electron transfer dissociation to pinpoint individual residues in the heavy chain of FVIIa whose conformation and/or local interaction pattern changes when the enzyme transitions to the active form, as induced either by its cofactor tissue factor or a covalent active site inhibitor. Identified regulatory residues are situated at key sites across one continuous surface of the protease domain spanning the TF-binding helix across the activation pocket to the calcium binding site and are embedded in elements of secondary structure and at the base of flexible loops. Thus these residues are optimally positioned to mediate crosstalk between functional sites in FVIIa, particularly the cofactor binding site and the active site. Our results unambiguously show that the conformational allosteric activation signal extends to the EGF1 domain in the light chain of FVIIa, underscoring a remarkable intra- and interdomain allosteric regulation of this trypsin-like protease. PMID:25344622

Song, Hongjian; Olsen, Ole H; Persson, Egon; Rand, Kasper D

2014-12-19

192

Production of transgenic goats expressing human coagulation factor IX in the mammary glands after nuclear transfer using transfected fetal fibroblast cells.  

PubMed

There are growing numbers of recombinant proteins that have been expressed in milk. Thus one can consider the placement of any gene of interest under the control of the regulatory elements of a milk protein gene in a dairy farm animal. Among the transgene introducing techniques, only nuclear transfer (NT) allows 100 % efficiency and bypasses the mosaicism associated with counterpart techniques. In this study, in an attempt to produce a transgenic goat carrying the human coagulation factor IX (hFIX) transgene, goat fetal fibroblasts were electroporated with a linearized marker-free construct in which the transgene was juxtaposed to ?-casein promoter designed to secret the recombinant protein in goat milk. Two different lines of transfected cells were used as donors for NT to enucleated oocytes. Two transgenic goats were liveborn. DNA sequencing of the corresponding transgene locus confirmed authenticity of the cloning procedure and the complementary experiments on the whey demonstrated expression of human factor IX in the milk of transgenic goats. In conclusion, our study has provided the groundwork for a prosperous and promising approach for large-scale production and therapeutic application of hFIX expressed in transgenic goats. PMID:22869287

Amiri Yekta, Amir; Dalman, Azam; Eftekhari-Yazdi, Poopak; Sanati, Mohammad Hossein; Shahverdi, Abdol Hossein; Fakheri, Rahman; Vazirinasab, Hamed; Daneshzadeh, Mohammad Taghi; Vojgani, Mahdi; Zomorodipour, Alireza; Fatemi, Nayeralsadat; Vahabi, Zeinab; Mirshahvaladi, Shahab; Ataei, Fariba; Bahraminejad, Elmira; Masoudi, Najmehsadat; Rezazadeh Valojerdi, Mojtaba; Gourabi, Hamid

2013-02-01

193

Transient blockade of the inducible costimulator pathway generates long-term tolerance to factor VIII after nonviral gene transfer into hemophilia A mice  

PubMed Central

Formation of inhibitory antibodies is a common problem encountered in clinical treatment for hemophilia. Human factor VIII (hFVIII) plasmid gene therapy in hemophilia A mice also leads to strong humoral responses. We demonstrate that short-term therapy with an anti-ICOS monoclonal antibody to transiently block the inducible costimulator/inducible costimulator ligand (ICOS/ICOSL) signaling pathway led to sustained tolerance to hFVIII in hFVIII plasmid–treated hemophilia A mice and allowed persistent, high-level FVIII functional activity (100%-300% of normal). Anti-ICOS treatment resulted in depletion of ICOS+CD4+ T cells and activation of CD25+Foxp3+ Tregs in the peripheral blood, spleen, and lymph nodes. CD4+ T cells from anti-ICOS–treated mice did not proliferate in response to hFVIII stimulation and produced high levels of regulatory cytokines, including interleukin-10 and transforming growth factor-?. Moreover, CD4+CD25+ Tregs from tolerized mice adoptively transferred dominant tolerance in syngeneic hFVIII plasmid-treated hemophilia A mice and reduced the production of antibodies against FVIII. Anti-ICOS–treated mice tolerized to hFVIII generated normal primary and secondary antibody responses after immunization with the T-dependent antigen, bacteriophage ?x 174, indicating maintenance of immune competency. Our data indicate that transient anti-ICOS monoclonal antibody treatment represents a novel single-agent immunomodulatory strategy to overcome the immune responses against transgene product after gene therapy. PMID:18574023

Peng, Baowei; Ye, Peiqing; Blazar, Bruce R.; Freeman, Gordon J.; Rawlings, David J.; Ochs, Hans D.

2008-01-01

194

The Charge Form Factor of the Neutron at Low Momentum Transfer from the $^{2}\\vec{\\rm H}(\\vec{\\rm e},{\\rm e}'{\\rm n}){\\rm p}$ Reaction  

E-print Network

We report new measurements of the neutron charge form factor at low momentum transfer using quasielastic electrodisintegration of the deuteron. Longitudinally polarized electrons at an energy of 850 MeV were scattered from an isotopically pure, highly polarized deuterium gas target. The scattered electrons and coincident neutrons were measured by the Bates Large Acceptance Spectrometer Toroid (BLAST) detector. The neutron form factor ratio $G^{n}_{E}/G^{n}_{M}$ was extracted from the beam-target vector asymmetry $A_{ed}^{V}$ at four-momentum transfers $Q^{2}=0.14$, 0.20, 0.29 and 0.42 (GeV/c)$^{2}$.

E. Geis; V. Ziskin; T. Akdogan; H. Arenhoevel; R. Alarcon; W. Bertozzi; E. Booth; T. Botto; J. Calarco; B. Clasie; C. B. Crawford; A. DeGrush; T. W. Donnelly; K. Dow; M. Farkhondeh; R. Fatemi; O. Filoti; W. Franklin; H. Gao; S. Gilad; D. Hasell; P. Karpius; M. Kohl; H. Kolster; T. Lee; A. Maschinot; J. Matthews; K. McIlhany; N. Meitanis; R. G. Milner; J. Rapaport; R. P. Redwine; J. Seely; A. Shinozaki; S. Sirca; A. Sindile; E. Six; T. Smith; M. Steadman; B. Tonguc; C. Tschalaer; E. Tsentalovich; W. Turchinetz; Y. Xiao; W. Xu; C. Zhang; Z. Zhou; T. Zwart

2008-04-08

195

In vivo expression of neutrophil inhibitory factor via gene transfer prevents lipopolysaccharide-induced lung neutrophil infiltration and injury by a beta2 integrin-dependent mechanism.  

PubMed Central

The binding of beta2 (CD18) integrins on PMN cell membrane to intercellular adhesion molecule (ICAM) counter-receptors on the surface of vascular endothelial cells mediates PMN adhesion to endothelial cells. Neutrophil inhibitory factor (NIF), a 41-kD glycoprotein isolated from the canine hookworm (Ancylostoma caninum), is a beta2 integrin antagonist that inhibits PMN adhesion to endothelial cells. We transferred the NIF gene into CD1 mouse lungs by intravenous injection of cationic liposomes to study the effects of in vivo NIF expression on LPS-induced lung PMN sequestration and the development of lung injury. RT-PCR and Northern blot analysis indicated the lung-selective expression of the NIF transgene, and immunocytochemistry showed prominent NIF expression in pulmonary microvessel endothelial cells. NIF staining was also observed in intraluminal leukocytes present in pulmonary microvessels. This may be the result of NIF binding to leukocytes after its secretion from the transduced lung cells, since there was no evidence of NIF gene expression in circulating leukocytes. Pulmonary vascular NIF expression abrogated the lung tissue PMN uptake and airspace migration of PMN and prevented lung vascular injury (as measured by the lung tissue uptake of [125I]labeled albumin) after the intraperitoneal LPS challenge (200 microg/mouse). Expression of a control protein, chloramphenicol acetyltransferase (CAT), by the same strategy, had no effect on these responses. In vitro studies showed that NIF prevented mouse PMN adhesion consistent with the inhibition of lung uptake after LPS challenge in NIF transgene-expressing mice. We conclude that pulmonary vascular expression of NIF, a specific beta2 integrin- binding protein, is a potentially useful gene transfer strategy in modulating the infiltration of PMN across the alveolar-capillary epithelial barrier and in preventing lung vascular endothelial injury. PMID:9616214

Zhou, M Y; Lo, S K; Bergenfeldt, M; Tiruppathi, C; Jaffe, A; Xu, N; Malik, A B

1998-01-01

196

Periluminal expression of a secreted transforming growth factor-? type II receptor inhibits in-stent neointima formation following adenovirus-mediated stent-based intracoronary gene transfer.  

PubMed

Transforming growth factor-?1 (TGF-?1) has been shown unequivocally to enhance neointima formation in carotid and ileo-femoral arteries. In our previous studies, however, TGF-?1 expression in coronary arteries actually reduced neointima formation without affecting luminal loss postangioplasty, while expression of a TGF-?1 antagonist (RIIs) in balloon-injured coronary arteries reduced luminal loss without affecting neointima formation. These observed effects may be a consequence of the mode of coronary artery gene transfer employed, but they may also represent differences in the modes of healing of coronary, carotid, and ileo-femoral arteries after endoluminal injury. To help clarify whether a gene therapy strategy to antagonize TGF-? might have application within the coronary vasculature, we have investigated the effect of high-level periluminal expression of RIIs using stent-based adenovirus-mediated intracoronary gene transfer. Porcine coronary arteries were randomized to receive a custom-made CoverStent preloaded with saline only, or with 1×10(9) infectious units of adenovirus expressing RIIs or ?-galactosidase (lacZ). Vessels were analyzed 28 days poststenting, at which time angiographic in-stent diameter was significantly greater in RIIs-treated arteries, and in-stent luminal loss significantly reduced. Computerized morphometric minimum in-stent lumen area was ~300% greater in RIIs-exposed vessels than in lacZ or saline-only groups. This was because of significantly reduced neointima formation in the RIIs group. RIIs had no demonstrable effect on cellular proliferation or apoptosis, but greater normalized neointimal/medial collagen content was observed in RIIs-exposed arteries. These data highlight the qualitatively similar effect of TGF-? antagonism on neointima formation in injured coronary and noncoronary arteries, and suggest that since cellular proliferation is unaffected, TGF-?1 antagonism might prevent in-stent restenosis without the delayed healing that is associated with drug-eluting stents in current clinical use. PMID:24483849

Appleby, Clare E; Ranjzad, Parisa; Williams, Paul D; Kakar, Salik J; Driessen, Anita; Tijsma, Edze; Fernandes, Brian; Heagerty, Anthony M; Kingston, Paul A

2014-05-01

197

Transfer factors to Whitetail deer: comparison of stomach-content, plant-sample and soil-sample concentrations as the denominator.  

PubMed

A recent study measured transfer factors for 49 elements in hunter-killed Whitetail deer (Odocoileus virginianus), using concentrations in the stomach content as the substrate/denominator to compute muscle/vegetation concentration ratios (CR(m-stomach)) and daily fractional transfer factors (Ff). Using the stomach content ensured an accurate representation of what the deer ate, except that it was limited in time to the vegetation selected by the animal just before it was killed. Here, two alternatives are considered, one where the feed is represented by samples of 21 different vegetation types that deer may have eaten in the area (CR(m-plant)), and the other is using soil concentration in the region as the denominator (CR(m-soil)). The latter is the formulation used in the ERICA tool, and other sources, for risk assessment to non-human biota. Across elements, (log) concentrations in all the media were highly correlated. The stomach contents had consistently higher ash and rare earth element concentrations than the sampled (and washed) vegetation and this was attributed to soil or dust ingestion. This lends credence to the use of soil-based CRm-soil values, despite (or more accurately because of) the inclusive yet gross simplicity of the approach. However, it was clear that variation of CR(m-soil) values was larger than for CR(m-stomach) or CR(m-plant), even if soil load on vegetation was included in the latter values. It was also noted that the variation in CR(m-soil) computed from the product of CR(m-plant) and CR(plant-soil) (where CR(plant-soil) is the plant/soil concentration ratio) was somewhat larger than the variation inherent in CR(m-soil) data. Thus it is reasonable to estimate CR(m-soil) from CR(m-plant) and CR(plant-soil) if observed CR(m-soil) values are not available, but this introduces further uncertainty. PMID:23287432

Sheppard, S C

2013-12-01

198

32 allocation of inner cell mass and trophectoderm cells of nuclear transfer embryos cultured in medium supplemented with epidermal growth factor and insulin-like growth factor-I.  

PubMed

This study was conducted to determine the additive effects of exogenous growth factors and different macromolecules during in vitro oocyte maturation (IVM) and sequential embryo culture of nuclear transfer (NT) embryos. Oocytes were matured in TCM-199 supplemented with 10% fetal calf serum (FCS), 50mgmL(-1) sodium pyruvate, 1% penicillin/streptomycin (10000UmL(-1) penicillin G, 10000mgmL(-1) streptomycin), 5mgmL(-1) LH, and 0.5mgmL(-1) FSH without growth factors (Treatment 1) or with 50ngmL(-1) epidermal growth factor (EGF; Treatment 2) or with 50ngmL(-1) EGF and 100ngmL(-1) insulin-like growth factor-I (IGF-1; Treatment 3). Cloned bovine embryos were produced by transferring granulosa cells into enucleated meiosis II oocytes. Following activation, reconstructed embryos were cultured in Quinn's Advantage Cleavage Medium (QACM) supplemented with 8mgmL(-1) essentially fatty-acid free (FAF) BSA for 72h. Then, developing embryos from granulosa cells were cultured in Sequential Quinn's Advantage Blastocyst Medium (QABM) supplemented with 4mgmL(-1) essentially FAF-BSA (Sigma-Aldrich, St. Louis, MO, USA)+5% FCS (Group 1), 4mgmL(-1) BSA+5% FCS+100ngmL(-1) IGF 1 (Group 2), and 4mgmL(-1) BSA+5% FCS+100ngmL(-1) IGF-1+50ngmL(-1) EGF (Group 3) for an additional 5 days under low oxygen tension (5% CO2, 5% O2, 90% N2) at 38.5°C in high humidity conditions. Maturation rates of oocytes matured in the presence of EGF (75.5%) and EGF+IGF-I combination (75.0%) were significantly higher than those of oocytes matured (63.8%) in the presence of only FCS (P<0.05). The developing NT embryos derived from granulosa cells of the Anatolian Grey Cattle showed no significant differences in fusion (53.62%, 53.25%, 57.36%), cleavage (67.98%, 74.20%, 66.80%), or blastocyst rates (32.65%, 29.47%, 41.77%) among culture groups (P>0.05). When 13 to 23 embryos per group were examined by using differential staining, the results showed that the IGF-I alone and combination with EGF in the sequential embryo culture medium (Group 2: 46.61%. and Group 3: 41.37%) significantly increased the number of inner cell mass (ICM)/total blastocyst cell ratio in comparison with Group 1 (29.32%, no IGF-I and EGF; P<0.05). Our results showed that the addition of growth factors to IVM medium and sequential culture medium changed the cell ration of cloned bovine embryos to the advance of ICM without changing total cell number. Supplementation of media with growth factors can alter the allocation of ICM and trophectoderm cells in NT embryos. PMID:25472081

Caputcu, A T; Arat, S; Cevik, M; Akkoc, T; Cetinkaya, G; Bagis, H

2014-12-01

199

Comparison of passively transferred antibodies in bighorn and domestic lambs reveals one factor in differential susceptibility of these species to Mannheimia haemolytica-induced pneumonia.  

PubMed

Mannheimia haemolytica consistently causes fatal bronchopneumonia in bighorn sheep (BHS; Ovis canadensis) under natural and experimental conditions. Leukotoxin is the primary virulence factor of this organism. BHS are more susceptible to developing fatal pneumonia than the related species Ovis aries (domestic sheep [DS]). In BHS herds affected by pneumonia, lamb recruitment is severely impaired for years subsequent to an outbreak. We hypothesized that a lack of maternally derived antibodies (Abs) against M. haemolytica provides an immunologic basis for enhanced susceptibility of BH lambs to population-limiting pneumonia. Therefore, the objective of this study was to determine the titers of Abs directed against M. haemolytica in the sera of BH and domestic lambs at birth through 12 weeks of age. Results revealed that BH lambs had approximately 18-fold lower titers of Ab against surface antigens of M. haemolytica and approximately 20-fold lower titers of leukotoxin-neutralizing Abs than domestic lambs. The titers of leukotoxin-neutralizing Abs in the serum and colostrum samples of BH ewes were approximately 157- and 50-fold lower than those for domestic ewes, respectively. Comparatively, the higher titers of parainfluenza 3 virus-neutralizing Abs in the BH lambs ruled out the possibility that these BHS had an impaired ability to passively transfer Abs to their lambs. These results suggest that lower levels of leukotoxin-neutralizing Abs in the sera of BH ewes, and resultant low Ab titers in their lambs, may be a critical factor in the poor lamb recruitment in herds affected by pneumonia. PMID:21613459

Herndon, Caroline N; Shanthalingam, Sudarvili; Knowles, Donald P; Call, Douglas R; Srikumaran, Subramaniam

2011-07-01

200

Variability of 137Cs and 40K soil-to-fruit transfer factor in tropical lemon trees during the fruit development period.  

PubMed

In this investigation we evaluate the soil uptake of (137)Cs and (40)K by tropical plants and their consequent translocation to fruits, by calculating the soil-to-fruit transfer factors defined as F(v) = [concentration of radionuclide in fruit (Bq kg(-1) dry mass)/concentration of radionuclide in soil (Bq kg(-1) dry mass in upper 20 cm)]. In order to obtain F(v) values, the accumulation of these radionuclides in fruits of lemon trees (Citrus limon B.) during the fruit growth was measured. A mathematical model was calibrated from the experimental data allowing simulating the incorporation process of these radionuclides by fruits. Although the fruit incorporates a lot more potassium than cesium, both radionuclides present similar absorption patterns during the entire growth period. F(v) ranged from 0.54 to 1.02 for (40)K and from 0.02 to 0.06 for (137)Cs. Maximum F(v) values are reached at the initial time of fruit growth and decrease as the fruit develops, being lowest at the maturation period. As a result of applying the model a decreasing exponential function is derived for F(v) as time increases. The agreement between the theoretical approach and the experimental values is satisfactory. PMID:22115437

Velasco, H; Cid, A S; Anjos, R M; Zamboni, C B; Rizzotto, M; Valladares, D L; Juri Ayub, J

2012-02-01

201

Defining the Disulfide Bonds of Insulin-like Growth Factor-binding Protein-5 by Tandem Mass Spectrometry with Electron Transfer Dissociation and Collision-induced Dissociation*  

PubMed Central

The six high-affinity insulin-like growth factor-binding proteins (IGFBPs) comprise a conserved family of secreted molecules that modulate IGF actions by regulating their half-life and access to signaling receptors, and also exert biological effects that are independent of IGF binding. IGFBPs are composed of cysteine-rich amino- (N-) and carboxyl- (C-) terminal domains, along with a cysteine-poor central linker segment. IGFBP-5 is the most conserved IGFBP, and contains 18 cysteines, but only 2 of 9 putative disulfide bonds have been mapped to date. Using a mass spectrometry (MS)-based strategy combining sequential electron transfer dissociation (ETD) and collision-induced dissociation (CID) steps, in which ETD fragmentation preferentially induces cleavage of disulfide bonds, and CID provides exact disulfide linkage assignments between liberated peptides, we now have definitively mapped 5 disulfide bonds in IGFBP-5. In addition, in conjunction with ab initio molecular modeling we are able to assign the other 4 disulfide linkages to within a GCGCCXXC motif that is conserved in five IGFBPs. Because of the nature of ETD fragmentation MS experiments were performed without chemical reduction of IGFBP-5. Our results not only establish a disulfide bond map of IGFBP-5 but also define a general approach that takes advantage of the specificity of ETD and the scalability of tandem MS, and the predictive power of ab initio molecular modeling to characterize unknown disulfide linkages in proteins. PMID:22117064

Nili, Mahta; Mukherjee, Aditi; Shinde, Ujwal; David, Larry; Rotwein, Peter

2012-01-01

202

Monitoring the activation state of the insulin-like growth factor-1 receptor and its interaction with protein tyrosine phosphatase 1B using bioluminescence resonance energy transfer.  

PubMed

We have developed two bioluminescence resonance energy transfer (BRET)-based approaches to monitor 1) ligand-induced conformational changes within partially purified insulin-like growth factor-1 (IGF-1) receptors (IGF1R) and 2) IGF1R interaction with a substrate-trapping mutant of protein tyrosine phosphatase 1B (PTP1B-D181A) in living cells. In the first assay, human IGF1R fused to Renilla reniformis luciferase (Rluc) or yellow fluorescent protein (YFP) were cotransfected in human embryonic kidney (HEK)-293 cells. The chimeric receptors were then partially purified by wheat germ lectin chromatography, and BRET measurements were performed in vitro. In the second assay, BRET measurements were performed on living HEK-293 cells cotransfected with IGF1R-Rluc and YFP-PTP1B-D181A. Ligand-induced conformational changes within the IGF1R and interaction of the IGF1R with PTP1B could be detected as an energy transfer between Rluc and YFP. Dose-response experiments with IGF-1, IGF-2, and insulin demonstrated that the effects of these ligands on BRET correlate well with their known pharmacological properties toward the IGF1R. Inhibition of IGF1R autophosphorylation by the tyrphostin AG1024 (3-bromo-5-t-butyl-4-hydroxy-benzylidenemalonitrile) resulted in the inhibition of IGF1-induced BRET signal between the IGF1R and PTP1B. In addition, an anti-IGF1R antibody known to inhibit the biological effects of IGF-1 inhibited ligand-induced BRET signal within the IGF1R, as well as between IGF1R and PTP1B. This inhibition of BRET signal paralleled the inhibition of the ligand-induced autophosphorylation of the IGF1R by this antibody. In conclusion, these BRET-based assays permit 1) the rapid evaluation of the effects of agonists or inhibitory molecules on IGF1R activation and 2) the analysis of the regulation of IGF1R-PTP1B interaction in living cells. PMID:15976035

Blanquart, Christophe; Boute, Nicolas; Lacasa, Danièle; Issad, Tarik

2005-09-01

203

Heat transfer coefficient and friction factor correlations for rectangular solar air heater duct having transverse wedge shaped rib roughness on the absorber plate  

Microsoft Academic Search

As is well known, the heat transfer coefficient of a solar air heater duct can be increased by providing artificial roughness on the heated wall (i.e. the absorber plate). Experiments were performed to collect heat transfer and friction data for forced convection flow of air in solar air heater rectangular duct with one broad wall roughened by wedge shaped transverse

J. L Bhagoria; J. S Saini; S. C Solanki

2002-01-01

204

Influence of tube-entrance configuration on average heat-transfer coefficients and friction factors for air flowing in an Inconel tube  

NASA Technical Reports Server (NTRS)

A heat-transfer investigation was conducted with air flowing through an electrically heated Inconel tube having either a long-approach or a right-angle-edge entrance, an inside diameter of 0.402 inch, and a length of 24 inches over a range of Reynolds numbers up to 375,000 and average inside-tube-wall temperatures up to 2000 degrees R. Good correlation of heat-transfer data was obtained for both entrances, which substantiates work previously reported. A fair correlation of friction data was obtained for both entrances. The entrance configuration had little effect on the average heat-transfer and friction coefficients.

Lowdermilk, Warren H; Grele, Milton D

1950-01-01

205

Electron transfer in peptides.  

PubMed

In this review, we discuss the factors that influence electron transfer in peptides. We summarize experimental results from solution and surface studies and highlight the ongoing debate on the mechanistic aspects of this fundamental reaction. Here, we provide a balanced approach that remains unbiased and does not favor one mechanistic view over another. Support for a putative hopping mechanism in which an electron transfers in a stepwise manner is contrasted with experimental results that support electron tunneling or even some form of ballistic transfer or a pathway transfer for an electron between donor and acceptor sites. In some cases, experimental evidence suggests that a change in the electron transfer mechanism occurs as a result of donor-acceptor separation. However, this common understanding of the switch between tunneling and hopping as a function of chain length is not sufficient for explaining electron transfer in peptides. Apart from chain length, several other factors such as the extent of the secondary structure, backbone conformation, dipole orientation, the presence of special amino acids, hydrogen bonding, and the dynamic properties of a peptide also influence the rate and mode of electron transfer in peptides. Electron transfer plays a key role in physical, chemical and biological systems, so its control is a fundamental task in bioelectrochemical systems, the design of peptide based sensors and molecular junctions. Therefore, this topic is at the heart of a number of biological and technological processes and thus remains of vital interest. PMID:25619931

Shah, Afzal; Adhikari, Bimalendu; Martic, Sanela; Munir, Azeema; Shahzad, Suniya; Ahmad, Khurshid; Kraatz, Heinz-Bernhard

2015-02-10

206

Iron deficiency leads to inhibition of oxygen transfer and enhanced formation of virulence factors in cultures of Pseudomonas aeruginosa PAO1  

Microsoft Academic Search

growth media with varied iron concentrations. In a computer-controlled bioreactor cultivation system for controlled dissolved oxygen tension (pO2), a strong correlation between the exhaustion of iron and the onset of oxygen limitation was observed. The oxygen transfer rate of the culture, characterized by the volumetric oxygen transfer coefficient, kLa, significantly decreased under iron-limited conditions. The formation of alginate and capsule

Eun-Jin Kim; Wael Sabra; An-Ping Zeng

2003-01-01

207

Examination of an inverted repeat within the F factor origin of transfer: context dependence of F TraI relaxase DNA specificity  

Microsoft Academic Search

Prior to conjugative transfer of plasmids, one plasmid strand is cleaved in a site- and strand-specific manner by an enzyme called a relaxase or nickase. In F and related plasmids, an inverted repeat is located near the plasmid strand cleavage site, and others have proposed that the ability of this sequence to form a hairpin when in single-stranded form is

Sarah L. Williams; Joel F. Schildbach

2006-01-01

208

Pathways to Teacher Education: Factors Critical to the Retention and Graduation of Community College Transfer Pre-Service Students in Teacher Education Programs.  

ERIC Educational Resources Information Center

Discusses the experiences of Piedmont Virginia Community College students who have transferred into the teacher education program at the University of Virginia's Curry School of Education. Makes recommendations for the improvement of such programs, such as monitoring cohort groups for the duration of the program and providing intensive advising.…

Wilson, Eleanor Vernon

2001-01-01

209

Astrophysical S factor for the radiative capture (12)N(p,gamma)(13)O determined from the (14)N((12)N,(13)O)(13)C proton transfer reaction  

E-print Network

The cross section of the radiative proton capture reaction on the drip line nucleus (12)N was investigated using the asymptotic normalization coefficient (ANC) method. We have used the (14)N((12)N,(13)O)(13)C proton transfer reaction at 12 Me...

Banu, A.; Al-Abdullah, T.; Fu, C.; Gagliardi, Carl A.; McCleskey, M.; Mukhamedzhanov, A. M.; Tabacaru, G.; Trache, L.; Tribble, Robert E.; Zhai, Y.; Carstoiu, F.; Burjan, V.; Kroha, V.

2009-01-01

210

Applicability of moisture transfer parameters estimated by correlation between Biot number and lag factor (Bi-G correlation) for convective drying of eggplant slices  

NASA Astrophysics Data System (ADS)

Accurate values of the moisture transfer parameters are necessary to study heat and mass transfer, particularly for the efficient design of both process and equipment. However, these parameters obtained from empirical equations or analytical solutions of Fick’s second diffusion law are generally different from each other. In order to make simulation more accurate and closer to the fact, it is necessary to perform theoretical analysis and test of available empirical equations in literatures. In this work, such efforts were made: firstly, moisture transfer parameters were evaluated by Bi-G correlation; then, the obtained parameters were substituted to Fick’s second law of diffusion model, and the model was numerically calculated with convective boundary condition. The results show that although the exponential equation fits the experimental data well, the data predicted from Fick’s second law deviate far from the experimental data. This implicates that Bi-G correlation need be further improved to obtain better accurate moisture transfer parameters.

Liu, Xianxi; Hou, Hongying; Chen, Junruo

2013-11-01

211

Behavior and Thought Change After a Self-Improvement Program: Studying the Effects of Environmental and Other Factors on the Transfer of Training  

Microsoft Academic Search

This study tested the attitude-behavior relationship and transfer of training on a specific training program -The Seven Habits of Highly Effective People. It is a self-improvement program designed to improve. such things as: interpersonal relationships, time management skills, and concentrating only on what one can change. The subjects were 84 BroMenn Healthcare employees signed up to take the training program.

JenniferBernstein

1994-01-01

212

Heat Transfer  

NSDL National Science Digital Library

Students explore heat transfer and energy efficiency using the context of energy efficient houses. They gain a solid understanding of the three types of heat transfer: radiation, convection and conduction, which are explained in detail and related to the real world. They learn about the many ways solar energy is used as a renewable energy source to reduce the emission of greenhouse gasses and operating costs. Students also explore ways in which a device can capitalize on the methods of heat transfer to produce a beneficial result. They are given the tools to calculate the heat transferred between a system and its surroundings.

Integrated Teaching and Learning Program,

213

Optimality and Conductivity for Water Flow: From Landscapes, to Unsaturated Soils, to Plant Leaves  

SciTech Connect

Optimality principles have been widely used in many areas. Based on an optimality principle that any flow field will tend toward a minimum in the energy dissipation rate, this work shows that there exists a unified form of conductivity relationship for three different flow systems: landscapes, unsaturated soils and plant leaves. The conductivity, the ratio of water flux to energy gradient, is a power function of water flux although the power value is system dependent. This relationship indicates that to minimize energy dissipation rate for a whole system, water flow has a small resistance (or a large conductivity) at a location of large water flux. Empirical evidence supports validity of the relationship for landscape and unsaturated soils (under gravity dominated conditions). Numerical simulation results also show that the relationship can capture the key features of hydraulic structure for a plant leaf, although more studies are needed to further confirm its validity. Especially, it is of interest that according to this relationship, hydraulic conductivity for gravity-dominated unsaturated flow, unlike that defined in the classic theories, depends on not only capillary pressure (or saturation), but also the water flux. Use of the optimality principle allows for determining useful results that are applicable to a broad range of areas involving highly non-linear processes and may not be possible to obtain from classic theories describing water flow processes.

Liu, H.H.

2012-02-23

214

Accumulation of heavy metals from contaminated soil to plants and evaluation of soil remediation by vermiculite.  

PubMed

We evaluated the distribution of 15 metal ions, namely Al, Cd, Cu, Cr, Fe, La, Mn, Ni, Pb, Sc, Ti, V, Y, Zn and Zr, in the soil of a contaminated site in Piedmont (Italy). This area was found to be heavily contaminated with Cu, Cr and Ni. The availability of these metal ions was studied using Tessier's sequential extraction procedure: the fraction of mobile species, which potentially is the most harmful for the environment, was much higher than that normally present in unpolluted soils. This soil was hence used to evaluate the effectiveness of treatment with vermiculite to reduce the availability of the pollutants to two plants, Lactuca sativa and Spinacia oleracea, by pot experiments. The results indicated that the addition of vermiculite significantly reduces the uptake of metal pollutants by plants, confirming the possibility of using this clay in amendment treatments of metal-contaminated soils. The effect of plant growth on metal fractionation in soils was investigated. Finally, the sum of the metal percentages extracted into the first two fractions of Tessier's protocol was found to be suitable in predicting the phytoavailability of most of the pollutants present in the investigated soil. PMID:21055788

Malandrino, Mery; Abollino, Ornella; Buoso, Sandro; Giacomino, Agnese; La Gioia, Carmela; Mentasti, Edoardo

2011-01-01

215

Experimental studies on heat transfer and friction factor characteristics of Al{sub 2}O{sub 3}/water nanofluid in a circular pipe under laminar flow with wire coil inserts  

SciTech Connect

In this paper, fully developed laminar flow convective heat transfer and friction factor characteristics of Al{sub 2}O{sub 3}/water nanofluid flowing through a uniformly heated horizontal tube with and without wire coil inserts is presented. For this purpose, Al{sub 2}O{sub 3} nanoparticles of 43 nm size were synthesized, characterized and dispersed in distilled water to form stable suspension containing 0.1% volume concentration of nanoparticles. The Nusselt number in the fully developed region were measured and found to increase by 12.24% at Re = 2275 for plain tube with nanofluid compared to distilled water. Two wire coil inserts made of stainless steel with pitch ratios 2 and 3 were used which increased the Nusselt numbers by 15.91% and 21.53% respectively at Re = 2275 with nanofluid compared to distilled water. The better heat transfer performance of nanofluid with wire coil insert is attributed to the effects of dispersion or back-mixing which flattens the temperature distribution and make the temperature gradient between the fluid and wall steeper. The measured pressure loss with the use of nanofluids is almost equal to that of the distilled water. The empirical correlations developed for Nusselt number and friction factor in terms of Reynolds/Peclet number, pitch ratio and volume concentration fits with the experimental data within {+-}15%. (author)

Chandrasekar, M.; Suresh, S. [Department of Mechanical Engineering, National Institute of Technology, Tiruchirappalli 620015 (India); Chandra Bose, A. [Nanomaterials Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli 620015 (India)

2010-02-15

216

Rhizobium nodulation protein NodA is a host-specific determinant of the transfer of fatty acids in Nod factor biosynthesis.  

PubMed

In the biosynthesis of lipochitin oligosaccharides (LCOs) the Rhizobium nodulation protein NodA plays an essential role in the transfer of an acyl chain to the chitin oligosaccharide acceptor molecule. The presence of nodA in the nodABCIJ operon makes genetic studies difficult to interpret. In order to be able to investigate the biological and biochemical functions of NodA, we have constructed a test system in which the nodA, nodB and nodC genes are separately present on different plasmids. Efficient nodulation was only obtained if nodC was present on a low-copy-number vector. Our results confirm the notion that nodA of Rhizobium leguminosarum biovar viciae is essential for nodulation on Vicia. Surprisingly, replacement of R. l. by viciae nodA by that of Bradyrhizobium sp. ANU289 results in a nodulation-minus phenotype on Vicia. Further analysis revealed that the Bradyrhizobium sp. ANU289 NodA is active in the biosynthesis of LCOs, but is unable to direct the transfer of the R. l. by, viciae nodFE-dependent multi-unsaturated fatty acid to the chitin oligosaccharide acceptor. These results lead to the conclusion that the original notion that nodA is a common nod gene should be revised. PMID:8628246

Ritsema, T; Wijfjes, A H; Lugtenberg, B J; Spaink, H P

1996-04-24

217

I k B a Gene Transfer Is Cytotoxic to Squamous-Cell Lung Cancer Cells and Sensitizes Them to Tumor Necrosis Factor a -Mediated Cell Death  

Microsoft Academic Search

Current paradigms in cancer therapy suggest that activation of nuclear factor- k B (NF- k B) by a variety of stimuli, including some cytoreductive agents, may inhibit apoptosis. Thus, inhibiting NF- k B activation may sensitize cells to anticancer therapy, thereby providing a more effective treatment for certain cancers. E-1-deleted adenoviral (Ad) vectors encoding a \\

Raj K. Batra; Denis C. Guttridge; David A. Brenner; Steven M. Dubinett; Albert S. Baldwin; Richard C. Boucher

218

Factors affecting the concentration in seven-spotted ladybirds (Coccinella septempunctata L.) of Cd and Zn transferred through the food chain.  

PubMed

The transfer of Cd and Zn from soils amended with sewage sludge was followed through a food chain consisting of wheat, aphids and the predator Coccinella septempunctata. Multiple regression models were generated to predict the concentrations of Cd and Zn in C. septempunctata. No significant model could be generated for Cd, indicting that the concentration of this metal was maintained within relatively narrow limits. A model predicting 64% of the variability in the Zn concentration of C. septempunctata was generated from of the concentration of Zn in the diet, time and rate of Zn consumption. The results suggest that decreasing the rate of food consumption is an effective mechanism to prevent the accumulation of Zn and that the availability of Zn in the aphid prey increased with the concentration in the aphids. The results emphasise the importance of using ecologically relevant food chains and exposure pathways during ecotoxicological studies. PMID:19683847

Green, I D; Diaz, A; Tibbett, M

2010-01-01

219

"Transfer Shock" or "Transfer Ecstasy?"  

ERIC Educational Resources Information Center

The alleged characteristic drop in grade point average (GPA) of transfer students and the subsequent rise in GPA was investigated in this study. No statistically significant difference was found in first term junior year GPA between junior college transfers and native Florida State University students after the variance accounted for by the…

Nickens, John M.

220

Generic approaches to transfer.  

PubMed

A review of methods which have been used to describe and predict transfer of radionuclides in biota was undertaken. The intent was to identify approaches that might prove useful in extending predictive estimates to other organisms and environments. Empirical approaches, such as found in the use of transfer factors, were examined. Kinetic methodologies were also presented. Allometric functions, with their ability to make broad generalizations, were also discussed. Data from several earlier radioecological assessments were tested for their potential utility in developing allometric relationships, with the result implying that such an approach might prove useful. PMID:17869391

Higley, K A; Bytwerk, D P

2007-01-01

221

Ultrahigh-Vacuum Sample-Transfer System  

NASA Technical Reports Server (NTRS)

Ultrahigh-vacuum (UHV) sample-transfer system developed features short-term (less than 30 minutes) transfer of samples from atmospheric pressure into sample manipulator within UHV analysis system without significantly degrading system pressure. New system is austere approach to sample transfer, involving no automation. Total cost of system is factor of 10 less than commercially available instruments.

Outlaw, R.; Baugh, B. T.

1985-01-01

222

On-bead combinatorial synthesis and imaging of chemical exchange saturation transfer magnetic resonance imaging agents to identify factors that influence water exchange.  

PubMed

The sensitivity of magnetic resonance imaging (MRI) contrast agents is highly dependent on the rate of water exchange between the inner sphere of a paramagnetic ion and bulk water. Normally, identifying a paramagnetic complex that has optimal water exchange kinetics is done by synthesizing and testing one compound at a time. We report here a rapid, economical on-bead combinatorial synthesis of a library of imaging agents. Eighty different 1,4,7,10-tetraazacyclododecan-1,4,7,10-tetraacetic acid (DOTA)-tetraamide peptoid derivatives were prepared on beads using a variety of charged, uncharged but polar, hydrophobic, and variably sized primary amines. A single chemical exchange saturation transfer image of the on-bead library easily distinguished those compounds having the most favorable water exchange kinetics. This combinatorial approach will allow rapid screening of libraries of imaging agents to identify the chemical characteristics of a ligand that yield the most sensitive imaging agents. This technique could be automated and readily adapted to other types of MRI or magnetic resonance/positron emission tomography agents as well. PMID:21793515

Napolitano, Roberta; Soesbe, Todd C; De León-Rodríguez, Luis M; Sherry, A Dean; Udugamasooriya, D Gomika

2011-08-24

223

Adeno-associated viral vector-mediated human vascular endothelial growth factor gene transfer stimulates angiogenesis and wound healing in the genetically diabetic mouse  

Microsoft Academic Search

  \\u000a \\u000a Aims\\/hypothesis. We studied the gene therapy efficacy of diabetes-associated wound healing disorder with an adeno-associated virus (AAV) vector\\u000a expressing the 165-amino acid isoform of human vascular endothelial growth factor-A (VEGF-A) by using an incisional skin-wound\\u000a model produced on the back of female diabetic C57BL\\/KsJ db+\\/db+ mice and their normal littermates (db+\\/+m).\\u000a \\u000a \\u000a \\u000a \\u000a Methods. Animals were randomized to receive intradermally into

M. Galeano; B. Deodato; D. Altavilla; D. Cucinotta; N. Arsic; H. Marini; V. Torre; M. Giacca; F. Squadrito

2003-01-01

224

Can't swallow, can't transfer, can't toilet: Factors predicting infections in the first week post stroke.  

PubMed

Post stroke infections are a significant clinical problem. Dysphagia occurs in approximately half of stroke patients and is associated with respiratory infections; however it is unclear what other factors contribute to an increased risk. This study aimed to determine which factors are most strongly predictive of infections in the first 7days post stroke admission. A retrospective review of 536 stroke patients admitted to Australian hospitals in 2010 was conducted. Data were collected on 37 clinical and demographic parameters. Univariate and multivariate logistic regression analysis was performed. The overall incidence of infection was 21%. Full assistance with mobility and incontinence on admission were associated with increased odds of general infection. Nil by mouth and presence of a nasogastric tube were significantly associated with patients developing respiratory infections. Urinary incontinence was a significant predictor for a urinary tract infection. Incidence of infection was highest on day two post admission. This study found enteral feeding, requiring full assistance with mobility and incontinence were significantly associated with developing infections in acute stroke. It contributes valuable new data from a large cohort of stroke patients demonstrating a period of susceptibility to infection in the very acute post stroke period. PMID:25174763

Brogan, Emily; Langdon, Claire; Brookes, Kim; Budgeon, Charley; Blacker, David

2015-01-01

225

Geo energy research and development: technology transfer  

SciTech Connect

Sandia Geo Energy Programs related to geothermal, coal, oil and gas, and synfuel resources have provided a useful mechanism for transferring laboratory technologies to private industry. Significant transfer of hardware, computer programs, diagnostics and instrumentation, advanced materials, and in situ process understanding has occurred through US/DOE supported programs in the past five years. The text briefly reviews the technology transfer procedures and summarizes 32 items that have been transferred and another 20 technologies that are now being considered for possible transfer to industry. A major factor in successful transfer has been personal interactions between Sandia engineers and the technical staff from private industry during all aspects of the technology development.

Traeger, R.K.

1982-03-01

226

Factors affecting 137Cs bio- availability under the application of different fertilizing systems  

NASA Astrophysics Data System (ADS)

Although it has been 25 years since the Chernobyl accident, it was generally found that radiocaesium remained bio-availability in some regions. Plant uptake of 137Cs is depended from quantity of exchangeable radionuclide and strongly influenced by soil properties. The addition of fertilizers to soil induces chemical and biological changes that influence the distribution of free ions the different phases (soil and soil solution). In this study we try to estimate influence of different soil conditions affecting the 137Cs bio-availability under the application of manure and inorganic fertilizers. Our research carried out in 2001-2008 years on contaminated after Chernobyl accident sod-podzolic soil during of prolonged field experiment. The experimental site was located in south-west of Bryansk region, Russia. Contamination density by 137Cs in the sampling point was equal to 475±30 kBq/m2. The sequence of crops in rotation was: 1) potato; 2) oats 3) lupine 4) winter rye. Three fertilizing systems were compared: organic - 80 tons per hectare of cow manure; inorganic fertilizing system - different rates of NPK (low, temperate and high) and mixed - 40 tons per hectare of cow manure + NPK. Main soil properties and chemical form of 137Cs and K (potassium) were detected. Radiocaesium activity was determined in soil and plant samples by gamma spectrometry, using a high purity Ge detectors. Overall efficiency was known to an accuracy of about 10-12%. Obtained results shows, that various fertilizing systems influence soil properties, chemical forms of 137Cs and K in soil and radionuclide soil-to-plant transfer in different ways. The highest reduction of exchangeable 137Cs in soil was found in case with application of organic fertilizers and also - temperate NPK rates. Part of exchangeable 137Cs is equal 6.8% (from total activity) in case of manure, 7.8% in case of inorganic fertilizers with control value - 10.2%. Caesium mobility in soil is affected by such soil properties as: soil pH< available phosphorus < humus content < exchangeable Ca2+ and Mg2+ < exchangeable K+. Inorganic fertilizers in high and temperate rates decrease 137Cs transfer to crops in 2.3-5.5 times. Organic fertilizers are less efficient, but its application can decrease 137Cs accumulation by farm crops during 2-3 years. Correlation analysis shows inversely proportional dependence between organic matter content and exchangeable form of 137Cs in soil (r2 = 0.81). A linear relation between 137Cs transfer factors (TF) to plants and exchangeable radionuclide content has been found (r2=0.68). Inversely proportional relation between the mobility level of potassium, its mobile form content and TF 137Cs was detected (r2 = 0.78).

Fedorkova, M. V.; Belova, N. I.

2012-04-01

227

Effects of recombinant adeno-associated virus-mediated CD151 gene transfer on the expression of rat vascular endothelial growth factor in ischemic myocardium  

PubMed Central

The aim of this study was to observe the effects of cluster of differentiation (CD) 151 on the expression of vascular endothelial growth factor (VEGF) in ischemic myocardium by the injection of a recombinant adeno-associated virus (rAAV) vector carrying the human CD151 gene. A rat acute myocardial infarction model was established, and rAAV-CD151 was injected into the ischemic myocardium. Four weeks later, the ischemic myocardium was removed in order to detect the expression of exogenous CD151 mRNA by reverse transcriptase polymerase chain reaction. In addition, the expression of CD151 and VEGF was detected by western blot analysis to evaluate the effect of CD151 overexpression on VEGF expression. Four weeks after injection of the vector, exogenous CD151 mRNA was expressed in the myocardial tissues of the CD151 group, whereas it was not detected in sham surgery, model control or rAAV-green fluorescent protein (GFP) gene-treated groups. The expression levels of CD151 protein were significantly higher in the CD151 group compared with those in the other three groups (P<0.05). The VEGF expression level in the CD151 group was higher compared with those in the control and GFP groups (P>0.05). These results indicate that rAAV-CD151 effectively transfects rat myocardial tissues, and may promote angiogenesis of the ischemic myocardium, improve left ventricular function and increase VEGF expression to improve ventricular function. PMID:25452800

FU, HAIRONG; TAN, JIAHUA; YIN, QI’NAN

2015-01-01

228

Adenoviral-mediated gene transfer of vascular endothelial growth factor in critical limb ischemia: safety results from a phase I trial.  

PubMed

Critical limb ischemia (CLI) is typified by rest pain and/or tissue necrosis secondary to advanced peripheral arterial disease (PAD) and is characterized by diminution in limb perfusion at rest. We tested the safety of an angiogenic strategy with CI-1023 (Ad(GV)VEGF121.10), a replication-deficient adenovirus encoding human vascular endothelial growth factor isoform 121 in patients with CLI as part of a phase I trial. Fifteen subjects >35 years of age with CLI and angiographic disease involving the infra-inguinal vessels underwent intramuscular injection of CI-1023 (4 x 10(8) to 4 x 10(10) particle units, n = 13) or placebo (n = 2). All of the patients tolerated the injection well and there were no serious complications related to the procedure. Transient edema was noted in one patient. A total of 79 adverse events were reported over the course of one year. One death (day 136) and one malignancy (day 332) occurred in the CI-1023 group. CI-1023 appears to be well tolerated and safe for single-dose administration in patients with critical limb ischemia due to PAD. Further studies are needed to determine the efficacy of this form of therapeutic angiogenesis. PMID:12866606

Mohler, Emile R; Rajagopalan, Sanjay; Olin, Jeffrey W; Trachtenberg, Jeffrey D; Rasmussen, Henrik; Pak, Raphael; Crystal, Ronald G

2003-01-01

229

Improved Survival of Ischemic Cutaneous and Musculocutaneous Flaps after Vascular Endothelial Growth Factor Gene Transfer Using Adeno-Associated Virus Vectors  

PubMed Central

A major challenge in reconstructive surgery is flap ischemia, which might benefit from induction of therapeutic angiogenesis. Here we demonstrate the effect of an adeno-associated virus (AAV) vector delivering vascular endothelial growth factor (VEGF)165 in two widely recognized in vivo flap models. For the epigastric flap model, animals were injected subcutaneously with 1.5 × 1011 particles of AAV-VEGF at day 0, 7, or 14 before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF was injected intramuscularly. The delivery of AAV-VEGF significantly improved flap survival in both models, reducing necrosis in all treatment groups compared to controls. The most notable results were obtained by administering the vector 14 days before flap dissection. In the transverse rectus abdominis musculocutaneous flap model, AAV-VEGF reduced the necrotic area by >50% at 1 week after surgery, with a highly significant improvement in the healing process throughout the following 2 weeks. The therapeutic effect of AAV-VEGF on flap survival was confirmed by histological evidence of neoangiogenesis in the formation of large numbers of CD31-positive capillaries and ?-smooth muscle actin-positive arteriolae, particularly evident at the border between viable and necrotic tissue. These results underscore the efficacy of VEGF-induced neovascularization for the prevention of tissue ischemia and the improvement of flap survival in reconstructive surgery. PMID:16192634

Zacchigna, Serena; Papa, Giovanni; Antonini, Andrea; Novati, Federico; Moimas, Silvia; Carrer, Alessandro; Arsic, Nikola; Zentilin, Lorena; Visintini, Valentina; Pascone, Michele; Giacca, Mauro

2005-01-01

230

Effects of recombinant adeno-associated virus-mediated CD151 gene transfer on the expression of rat vascular endothelial growth factor in ischemic myocardium.  

PubMed

The aim of this study was to observe the effects of cluster of differentiation (CD) 151 on the expression of vascular endothelial growth factor (VEGF) in ischemic myocardium by the injection of a recombinant adeno-associated virus (rAAV) vector carrying the human CD151 gene. A rat acute myocardial infarction model was established, and rAAV-CD151 was injected into the ischemic myocardium. Four weeks later, the ischemic myocardium was removed in order to detect the expression of exogenous CD151 mRNA by reverse transcriptase polymerase chain reaction. In addition, the expression of CD151 and VEGF was detected by western blot analysis to evaluate the effect of CD151 overexpression on VEGF expression. Four weeks after injection of the vector, exogenous CD151 mRNA was expressed in the myocardial tissues of the CD151 group, whereas it was not detected in sham surgery, model control or rAAV-green fluorescent protein (GFP) gene-treated groups. The expression levels of CD151 protein were significantly higher in the CD151 group compared with those in the other three groups (P<0.05). The VEGF expression level in the CD151 group was higher compared with those in the control and GFP groups (P>0.05). These results indicate that rAAV-CD151 effectively transfects rat myocardial tissues, and may promote angiogenesis of the ischemic myocardium, improve left ventricular function and increase VEGF expression to improve ventricular function. PMID:25452800

Fu, Hairong; Tan, Jiahua; Yin, Qi'nan

2015-01-01

231

Adenoviral-Mediated Glial Cell Line–Derived Neurotrophic Factor Gene Transfer Has a Protective Effect on Sciatic Nerve Following Constriction-Induced Spinal Cord Injury  

PubMed Central

Neuropathic pain due to peripheral nerve injury may be associated with abnormal central nerve activity. Glial cell-line-derived neurotrophic factor (GDNF) can help attenuate neuropathic pain in different animal models of nerve injury. However, whether GDNF can ameliorate neuropathic pain in the spinal cord dorsal horn (SCDH) in constriction-induced peripheral nerve injury remains unknown. We investigated the therapeutic effects of adenoviral-mediated GDNF on neuropathic pain behaviors, microglial activation, pro-inflammatory cytokine expression and programmed cell death in a chronic constriction injury (CCI) nerve injury animal model. In this study, neuropathic pain was produced by CCI on the ipsilateral SCDH. Mechanical allodynia was examined with von Frey filaments and thermal sensitivity was tested using a plantar test apparatus post-operatively. Target proteins GDNF-1, GDNFRa-1, MMP2, MMP9, p38, phospho-p38, ED1, IL6, IL1?, AIF, caspase-9, cleaved caspase-9, caspase-3, cleaved caspase-3, PARP, cleaved PARP, SPECTRIN, cleaved SPECTRIN, Beclin-1, PKC?, PKC?, iNOS, eNOS and nNOS were detected. Microglial activity was measured by observing changes in immunoreactivity with OX-42. NeuN and TUNEL staining were used to reveal whether apoptosis was attenuated by GDNF. Results showed that administrating GDNF began to attenuate both allodynia and thermal hyperalgesia at day 7. CCI-rats were found to have lower GDNF and GDNFRa-1 expression compared to controls, and GDNF re-activated their expression. Also, GDNF significantly down-regulated CCI-induced protein expression except for MMP2, eNOS and nNOS, indicating that the protective action of GDNF might be associated with anti-inflammation and prohibition of microglia activation. Immunocytochemistry staining showed that GDNF reduced CCI-induced neuronal apoptosis. In sum, GDNF enhanced the neurotrophic effect by inhibiting microglia activation and cytokine production via p38 and PKC signaling. GDNF could be a good therapeutic tool to attenuate programmed cell death, including apoptosis and autophagy, consequent to CCI-induced peripheral nerve injury. PMID:24642655

Chou, An-Kuo; Yang, Ming-Chang; Tsai, Hung-Pei; Chai, Chee-Yin; Tai, Ming-Hong; Kwan, Aij-Li; Hong, Yi-Ren

2014-01-01

232

New Empirical Equation for the Atomic Form Factor Function in the Momentum Transfer Range, q?=?0–50 Å?1 for the Elements in the Range 1? Z ?30  

PubMed Central

The importance of Atomic Form Factors (f) is well-known to the scientific community. Tabulated values for f are mostly used in calculating cross-sections and Monte Carlo sampling for the coherent scattering of photons. The uses of these values are subjected to different approximations and interpolation techniques because the available data points for f in the literature for specified momentum-transfer-grids are very limited. In order to make it easier to accurately use the tabulated data, a mathematical expression for f functions would be a great achievement. Therefore, the current study was designed to suggest an empirical expression for the f functions. In the results, an empirical equation for Hubbell's tabulated data for f is created in the momentum transfer range, q?=?0–50 Å?1 for the elements in the range 1? Z ?30. The number of applied parameters was seven. The fitting to f showed that the maximum deviation was within 3%, 4% and 5% for the element having, Z?=?1–11, Z?=?12–22 and Z?=?23–30, respectively, while the average deviations were within 0.3–2.25% for all elements (i.e., Z?=?1–30). The values generated by the analytical equation were used in the Monte Carlo code instead of Hubbell’s tabulated values. The statistical noise in the Probability Distribution Functions of coherently scattered photons was efficiently removed. Furthermore, it also reduced the dependence on different interpolation techniques and approximations, and on the use of large tabulated data for f with the specified elements. PMID:23936339

Muhammad, Wazir; Lee, Sang Hoon

2013-01-01

233

Animal Transfer Agreement -1 ANIMAL TRANSFER AGREEMENT  

E-print Network

Animal Transfer Agreement - 1 ANIMAL TRANSFER AGREEMENT This Animal Transfer Agreement has been adopted for use by the National Institutes of Health (NIH) for use in transferring animals for research transferring the animal) Recipient: (name of laboratory/institution receiving the animal) The Provider agrees

Bandettini, Peter A.

234

Evidence for the transfer of polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans from soil into biota.  

PubMed

The concentrations of six indicator and co-planar polychlorinated biphenyls (PCBs), 17 polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans (PCDD/Fs) were determined in soil and associated biota samples collected from a polluted and wasted farmland in southern China. The sum of six indicator PCBs (Nos 28, 52, 101, 138, 153 and 180) concentrations in biota samples were proportional to the total amount of PCBs that transferred from soil to the corresponding biota samples, and the sum six indicator PCB congeners in samples were about 20% of the total PCBs, respectively. The ratios of the sum six indicator PCBs and the total PCBs in samples collected in the same area were approximately equal. The sums of six indicator PCBs were proportional to the total PCBs that transferred from soil to plant, while the co-planar PCBs were not. Analysis of individual PCB and PCDD/F congener signatures in soil revealed the original pollutant source after transportation and biodegradation for 14 years using principal component analysis (PCA). The pattern of PCBs in soils and plants could reflect the original pollution source after transportation and biodegradation for 14 years, while the pattern of PCBs in the terrestrial animals could not reflect the primary source. The consumption foods in this region such as foraging chicken eggs, foraging duck eggs, and loach (Misgurnus anguillicaudatus) were highly contaminated, the total toxicity equivalent (TEQ) was up to 784 pg WHO-TEQ/g on basis lipid in foraging chicken eggs. PMID:16574199

Zhao, Xingru; Zheng, Minghui; Zhang, Bing; Zhang, Qinghua; Liu, Wenbin

2006-09-15

235

Transfer functions  

NASA Technical Reports Server (NTRS)

The vulnerability of electronic equipment to carbon fibers is studied. The effectiveness of interfaces, such as filters, doors, window screens, and cabinets, which affect the concentration, exposure, or deposition of carbon fibers on both (internal and external) sides of the interface is examined. The transfer function of multilayer aluminum mesh, wet and dry, polyurethane foam, and window screen are determined as a function of air velocity. FIlters installed in typical traffic control boxes and air conditioners are also considered.

Taback, I.

1979-01-01

236

Nonadiabatic anharmonic electron transfer  

SciTech Connect

The effect of an inner sphere, local mode vibration on an electron transfer is modeled using the nonadiabatic transition probability (rate) expression together with both the anharmonic Morse and the harmonic oscillator potential. For an anharmonic inner sphere mode, a variational analysis uses harmonic oscillator basis functions to overcome the difficulties evaluating Morse-model Franck-Condon overlap factors. Individual matrix elements are computed with the use of new, fast, robust, and flexible recurrence relations. The analysis therefore readily addresses changes in frequency and/or displacement of oscillator minimums in the different electron transfer states. Direct summation of the individual Boltzmann weighted Franck-Condon contributions avoids the limitations inherent in the use of the familiar high-temperature, Gaussian form of the rate constant. The effect of harmonic versus anharmonic inner sphere modes on the electron transfer is readily seen, especially in the exoergic, inverted region. The behavior of the transition probability can also be displayed as a surface for all temperatures and values of the driving force/exoergicity {Delta}=-{Delta}G. The temperature insensitivity of the transfer rate is clearly seen when the exoergicity equals the collective reorganization energy ({Delta}={Lambda}{sub s}) along a maximum ln (w) vs. {Delta} ridge of the surface. The surface also reveals additional regions for {Delta} where ln (w) appears to be insensitive to temperature, or effectively activationless, for some kinds of inner sphere contributions.

Schmidt, P. P. [Molecular Physics Research, 6547 Kristina Ursula Court, Falls Church, Virginia 22044 (United States)

2013-03-28

237

Nonadiabatic anharmonic electron transfer.  

PubMed

The effect of an inner sphere, local mode vibration on an electron transfer is modeled using the nonadiabatic transition probability (rate) expression together with both the anharmonic Morse and the harmonic oscillator potential. For an anharmonic inner sphere mode, a variational analysis uses harmonic oscillator basis functions to overcome the difficulties evaluating Morse-model Franck-Condon overlap factors. Individual matrix elements are computed with the use of new, fast, robust, and flexible recurrence relations. The analysis therefore readily addresses changes in frequency and/or displacement of oscillator minimums in the different electron transfer states. Direct summation of the individual Boltzmann weighted Franck-Condon contributions avoids the limitations inherent in the use of the familiar high-temperature, gaussian form of the rate constant. The effect of harmonic versus anharmonic inner sphere modes on the electron transfer is readily seen, especially in the exoergic, inverted region. The behavior of the transition probability can also be displayed as a surface for all temperatures and values of the driving force/exoergicity ? = -?G. The temperature insensitivity of the transfer rate is clearly seen when the exoergicity equals the collective reorganization energy (? = ?(s)) along a maximum ln?(w) vs. ? ridge of the surface. The surface also reveals additional regions for ? where ln?(w) appears to be insensitive to temperature, or effectively activationless, for some kinds of inner sphere contributions. PMID:23556710

Schmidt, P P

2013-03-28

238

The transfer of analytical procedures.  

PubMed

Analytical method transfers are certainly among the most discussed topics in the GMP regulated sector. However, they are surprisingly little regulated in detail. General information is provided by USP, WHO, and ISPE in particular. Most recently, the EU emphasized the importance of analytical transfer by including it in their draft of the revised GMP Guideline. In this article, an overview and comparison of these guidelines is provided. The key to success for method transfers is the excellent communication between sending and receiving unit. In order to facilitate this communication, procedures, flow charts and checklists for responsibilities, success factors, transfer categories, the transfer plan and report, strategies in case of failed transfers, tables with acceptance limits are provided here, together with a comprehensive glossary. Potential pitfalls are described such that they can be avoided. In order to assure an efficient and sustainable transfer of analytical procedures, a practically relevant and scientifically sound evaluation with corresponding acceptance criteria is crucial. Various strategies and statistical tools such as significance tests, absolute acceptance criteria, and equivalence tests are thoroughly descibed and compared in detail giving examples. Significance tests should be avoided. The success criterion is not statistical significance, but rather analytical relevance. Depending on a risk assessment of the analytical procedure in question, statistical equivalence tests are recommended, because they include both, a practically relevant acceptance limit and a direct control of the statistical risks. However, for lower risk procedures, a simple comparison of the transfer performance parameters to absolute limits is also regarded as sufficient. PMID:23978903

Ermer, J; Limberger, M; Lis, K; Wätzig, H

2013-11-01

239

AAV-dominant negative tumor necrosis factor (DN-TNF) gene transfer to the striatum does not rescue medium spiny neurons in the YAC128 mouse model of Huntington's disease.  

PubMed

CNS inflammation is a hallmark of neurodegenerative disease, and recent studies suggest that the inflammatory response may contribute to neuronal demise. In particular, increased tumor necrosis factor (TNF) signaling is implicated in the pathology of both Parkinson's disease (PD) and Alzheimer's disease (AD). We have previously shown that localized gene delivery of dominant negative TNF to the degenerating brain region can limit pathology in animal models of PD and AD. TNF is upregulated in Huntington's disease (HD), like in PD and AD, but it is unknown whether TNF signaling contributes to neuronal degeneration in HD. We used in vivo gene delivery to test whether selective reduction of soluble TNF signaling could attenuate medium spiny neuron (MSN) degeneration in the YAC128 transgenic (TG) mouse model of Huntington's disease (HD). AAV vectors encoding cDNA for dominant-negative tumor necrosis factor (DN-TNF) or GFP (control) were injected into the striatum of young adult wild type WT and YAC128 TG mice and achieved 30-50% target coverage. Expression of dominant negative TNF protein was confirmed immunohistologically and biochemically and was maintained as mice aged to one year, but declined significantly over time. However, the extent of striatal DN-TNF gene transfer achieved in our studies was not sufficient to achieve robust effects on neuroinflammation, rescue degenerating MSNs or improve motor function in treated mice. Our findings suggest that alternative drug delivery strategies should be explored to determine whether greater target coverage by DN-TNF protein might afford some level of neuroprotection against HD-like pathology and/or that soluble TNF signaling may not be the primary driver of striatal neuroinflammation and MSN loss in YAC128 TG mice. PMID:24824433

Alto, Laura Taylor; Chen, Xi; Ruhn, Kelly A; Treviño, Isaac; Tansey, Malú G

2014-01-01

240

Considering factors beyond transfer of conceptual knowledge  

NSDL National Science Digital Library

One thread in education research has been to investigate whether and in what ways students âtransferâ conceptual knowledge from one context to another. We argue that in understanding studentsâ reasoning across contexts, it can additionally be productive to attend to their epistemological framing. We present a case study of one student (Will), whose reasoning on two similarly structured approximation problems does not draw on pieces of conceptual knowledge across contexts in a manner that experts might view as productive. We further show that attending to Willâs epistemological framing aids our understanding of why he draws on different types of knowledge on the two problems.

Kuo, Eric; Champney, Danielle; Little, Angela

2013-12-17

241

Transferability of tubifex limiting factor models  

USGS Publications Warehouse

Dense populations of T. tubifex are generally associated with habitats dominated by fine sediments and enriched organic material (e.g. Krueger, 2002). Management of whirling disease positive systems is entering a new phase where channel modifications are being implemented to reduce or isolate this type of habitat. These management actions have the potential to cause new areas of sediment deposition. Descriptions of sediment characteristics associated with high numbers of T. tubifex can help engineers design channel modifications that minimize situations where altered velocity distributions inadvertently create optimum worm habitat. Ongoing studies in two Colorado Rivers with very different flow regimes and watershed characteristics provide preliminary evidence that a median sediment particle diameter greater than 1.4mm in conjunction with at least 30% (dry weight) of sediment with a diameter less than 0.3mm limits T. tubifex densities to approximately less than 10% of maximum densities.

Terrell, James W.; Milhous, Robert T.

2004-01-01

242

Analogical Transfer from a Simulated Physical System  

ERIC Educational Resources Information Center

Previous research has consistently found that spontaneous analogical transfer is strongly tied to concrete and contextual similarities between the cases. However, that work has largely failed to acknowledge that the relevant factor in transfer is the similarity between individuals' mental representations of the situations rather than the overt…

Day, Samuel B.; Goldstone, Robert L.

2011-01-01

243

Food chain transfer and potential renal toxicity of mercury to small mammals at a contaminated terrestrial field site.  

PubMed

Mercury concentrations were determined in surface soil and biota at a contaminated terrestrial field site and were used to calculate transfer coefficients of mercury through various compartments of the ecosystem based on trophic relationships. Mercury concentrations in all compartments (soil, vegetation, invertebrates, and small mammals) were higher than mercury concentrations in corresponding samples at local reference sites. Nonetheless, mercury concentrations in biota did not exceed concentrations in the contaminated surface soil, which averaged 269 ?g g(-1). Plant tissue concentrations of mercury were low (0.01 to 2.0 ?g g(-1)) and yielded soil to plant transfer coefficients ranging from 3.7×10(-5) for seeds to 7.0×10(-3) for grass blades. Mercury concentrations in invertebrates ranged from 0.79 for harvestmen (Phalangida) to 15.5 ?g g(-1) for undepurated earthworms (Oligochaeta). Mean food chain transfer coefficients for invertebrates were 0.88 for herbivores/omnivores and 2.35 for carnivores. Mean mercury concentrations in target tissue (kidney) were 1.16±1.16 ?g g(-1) for the white-footed mouse (Peromyscus leucopus), a granivore, and 38.8±24.6 ?g g(-1) for the shorttail shrew (Blarina brevicauda), an insectivore. Transfer coefficients for diet to kidney were 0.75 and 4.40 for P. leucopus and B. brevicauda, respectively. A comparison of kidney mercury residues measured in this study with values from controlled laboratory feeding studies from the literature indicate that B. brevicauda but not P. leucopus may be ingesting mercury at levels that are nephrotoxic. PMID:24201735

Talmage, S S; Walton, B T

1993-12-01

244

Electron transfer dissociation (ETD): The mass spectrometric breakthrough essential for O-GlcNAc protein site assignments – A study of the O-GlcNAcylated protein Host Cell Factor C1  

PubMed Central

The development of electron-based, unimolecular dissociation mass spectrometric methods, i.e. electron capture and electron transfer dissociation (ECD and ETD, respectively), has greatly increased the speed and reliability of labile post-translational modification (PTM) site assignment. The field of intracellular O-GlcNAc (O-linked N-acetylglucosamine) signaling has especially advanced with the advent of ETD mass spectrometry. Only within the last five years have proteomic-scale experiments utilizing ETD allowed the assignment of hundreds of O-GlcNAc sites within cells and subcellular structures. Our ability to identify and unambiguously assign the site of O-GlcNAc modifications using ETD is rapidly increasing our understanding of this regulatory glycosylation and its potential interaction with other PTMs. Here, we discuss the advantages of using ETD, complimented with collisional-activation mass spectrometry (CID/CAD), in a study of O-GlcNAc modified peptides of the extensively O-GlcNAcylated protein Host Cell Factor C1 (HCF-1). HCF-1 is a transcriptional co-regulator, forms a stable complex with O-GlcNAc transferase and is involved in control of cell cycle progression. ETD, along with higher energy collisional dissociation (HCD) mass spectrometry, was employed to assign the PTMs of the HCF-1 protein isolated from HEK293T cells. These include nineteen sites of O-GlcNAcylation, two sites of phosphorylation and two sites bearing dimethylarginine, and showcase the residue-specific, PTM complexity of this regulator of cell proliferation. PMID:23335398

Myers, Samuel A.; Daou, Salima; Affar, El Bachir; Burlingame, AL

2014-01-01

245

Engineering heat transfer  

SciTech Connect

The work is in three sections: conduction, convection, and radiation heat transfer. The contents includes: The general conduction equation. Heat transfer from extended surfaces. Steady-state conduction in multiple dimensions. Convection heat transfer in a closed conduit. Natural-convection systems. Heat exchangers. Condensation and vaporization heat transfer. Radiation heat transfer between surfaces.

Janna, W.S.

1986-01-01

246

Human immunodeficiency virus tat gene transfer to the murine central nervous system using a replication-defective herpes simplex virus vector stimulates transforming growth factor beta 1 gene expression.  

PubMed Central

The high incidence of neurological disorders in patients afflicted with acquired immunodeficiency syndrome (AIDS) may result from human immunodeficiency virus type 1 (HIV-1) induction of chemotactic signals and cytokines within the brain by virus-encoded gene products. Transforming growth factor beta1 (TGF-beta1) is an immunomodulator and potent chemotactic molecule present at elevated levels in HIV-1-infected patients, and its expression may thus be induced by viral trans-activating proteins such as Tat. In this report, a replication-defective herpes simplex virus (HSV)-1 tat gene transfer vector, dSTat, was used to transiently express HIV-1 Tat in glial cells in culture and following intracerebral inoculation in mouse brain in order to directly determine whether Tat can increase TGF-beta1 mRNA expression. dSTat infection of Vero cells transiently transfected by a panel of HIV-1 long terminal repeat deletion mutants linked to the bacterial chloramphenicol acetyltransferase reporter gene demonstrated that vector-expressed Tat activated the long terminal repeat in a trans-activation response element-dependent fashion independent of the HSV-mediated induction of the HIV-1 enhancer, or NF-kappaB domain. Northern blot analysis of human astrocytic glial U87-MG cells transfected by dSTat vector DNA resulted in a substantial increase in steady-state levels of TGF-beta1 mRNA. Furthermore, intracerebral inoculation of dSTat followed by Northern blot analysis of whole mouse brain RNA revealed an increase in levels of TGF-beta1 mRNA similar to that observed in cultured glial cells transfected by dSTat DNA. These results provided direct in vivo evidence for the involvement of HIV-1 Tat in activation of TGF-beta1 gene expression in brain. Tat-mediated stimulation of TGF-beta1 expression suggests a novel pathway by which HIV-1 may alter the expression of cytokines in the central nervous system, potentially contributing to the development of AIDS-associated neurological disease. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8650221

Rasty, S; Thatikunta, P; Gordon, J; Khalili, K; Amini, S; Glorioso, J C

1996-01-01

247

Investigation on Convective Heat Transfer and Flow Features of Nanofluids  

Microsoft Academic Search

With progresses of thermoscience and thermal engineering, many efforts have been devoted to heat transfer enhancement. Among them, application of additives to liquids is often involved. Since the flow media themselves may be the controlling factor of limiting heat transfer performance, solid additives are suspended in the base liquids in order to change transport properties, flow and heat transfer features

Yimin Xuan; Qiang Li

2003-01-01

248

Effects of new ventures' social network on knowledge transfer  

Microsoft Academic Search

Effective knowledge transfer in new ventures' social network has been one of many factors crucial to new ventures' survival and growth. This paper explores the effects of new ventures' social network on knowledge transfer. The results show that network structure has significant effects on transferring knowledge to new ventures. High density, greater centrality, heterogeneity and lager size in new ventures'

Yahao Mei; Hongli Liu

2011-01-01

249

Transfer of Training: A Meta-Analytic Review  

Microsoft Academic Search

Although transfer of learning was among the very first issues addressed by early psychologists, the extant literature remains characterized by inconsistent measurement of transfer and significant variability in findings. This article presents a meta-analysis of 89 empirical studies that explore the impact of predictive factors (e.g., trainee characteristics, work environment, training interventions) on the transfer of training to different tasks

Brian D. Blume; J. Kevin Ford; Timothy T. Baldwin; Jason L. Huang

2010-01-01

250

Hole transfer kinetics of DNA.  

PubMed

Not long after the discovery of the double-helical structure of DNA in 1952, researchers proposed that charge transfer along a one-dimensional ?-array of nucleobases might be possible. At the end of the 1990s researchers discovered that a positive charge (a hole) generated in DNA migrates more than 200 Å along the structure, a discovery that ignited interest in the charge-transfer process in DNA. As a result, DNA became an interesting potential bottom-up material for constructing nanoelectronic sensors and devices because DNA can form various complex two-dimensional and three-dimensional structures, such as smiley faces and cubes. From the fundamental aspects of the hole transfer process, DNA is one of the most well-studied organic molecules with many reports on the synthesis of artificial nucleobase analogues. Thus, DNA offers a unique system to study how factors such as the HOMO energy and molecular flexibility affect hole transfer kinetics. Understanding the hole transfer mechanism requires a discussion of the hole transfer rate constants (kHT). This Account reviews the kHT values determined by our group and by Lewis and Wasielewski's group, obtained by a combination of the synthesis of modified DNA and time-resolved spectroscopy. DNA consists of G/C and A/T base pairs; the HOMO localizes on the purine bases G and A, and G has a lower oxidation potential and a higher energy HOMO. Typically, long-range hole transfer proceeded via sequential hole transfer between G/C's. The kinetics of this process in DNA sequences, including those with mismatches, is reproducible via kinetic modeling using the determined kHT for each hole transfer step between G/C's. We also determined the distance dependence parameter (?), which describes the steepness of the exponential decrease of kHT. Because of this value, >0.6 Å(-1) for hole transfer in DNA, DNA itself does not serve as a molecular wire. Interestingly, hole transfer proceeded exceptionally fast for some sequences in which G/C's are located close to each other, an observation that we cannot explain by a simple sequential hole transfer between G/C's but rather through hole delocalization over the nucleobases. To further investigate and refine the factors that affect kHT, we examined various artificial nucleobases. We clearly demonstrated that kHT depends strongly on the HOMO energy gap between the bases (?HOMO), and that kHT can be increased with decreasing ?HOMO. We reduced ?HOMO between the two type of base pairs by replacing adenines (A's) with deazaadenines ((z)A's) or diaminopurines (D's) and showed that the hole transfer rate through the G/C and A/T mix sequence increased by more than 3 orders of magnitude. We also investigated how DNA flexibility affects kHT. Locked nucleic acid (LNA) modification, which makes DNA more rigid, lowered kHT by more than 2 orders of magnitude. On the other hand, 5-Me-2'-deoxyzebularine (B) modification, which increases DNA flexibility, increased kHT by more than 1 order of magnitude. These new insights in hole transfer kinetics obtained from modified DNAs may aid in the design of new molecular-scale conducting materials. PMID:23805774

Kawai, Kiyohiko; Majima, Tetsuro

2013-11-19

251

Manifestations of sequential electron transfer  

SciTech Connect

An essential feature of efficient photo-initiated charge separation is sequential electron transfer. Charge separation is initiated by photoexcitation of an electron donor followed by rapid electron transfer steps from the excited donor through a series of electron acceptors, so that, after one or two successive steps, charge separation is stabilized by the physical separation between the oxidized donor and reduced acceptor. The prime example of this process is the sequential electron transfer that takes place in the purple photosynthetic bacterial reaction center, resulting in the charge separation between P{sup +} and Q{sub A}{sup -} across a biological membrane. We have developed magnetic resonance tools to monitor sequential electron transfer. We are applying these techniques to study charge separation in natural photo-synthetic systems in order to gain insights into the features of the reaction center proteins that promote efficient charge separation. As we establish what some of these factors are, we are beginning to design artificial photosynthetic systems that undergo photoinduced sequential electron transfer steps.

Thurnauer, M.C.; Tang, J.

1996-05-01

252

Maternal immune transfer in mollusc.  

PubMed

Maternal immunity refers to the immunity transferred from mother to offspring via egg, playing an important role in protecting the offspring at early life stages and contributing a trans-generational effect on offspring's phenotype. Because fertilization is external in most of the molluscs, oocytes and early embryos are directly exposed to pathogens in the seawater, and thus maternal immunity could provide a better protection before full maturation of their immunological systems. Several innate immune factors including pattern recognition receptors (PRRs) like lectins, and immune effectors like lysozyme, lipopolysaccharide binding protein/bacterial permeability-increasing proteins (LBP/BPI) and antioxidant enzymes have been identified as maternally derived immune factors in mollusc eggs. Among these immune factors, some maternally derived lectins and antibacterial factors have been proved to endue mollusc eggs with effective defense ability against pathogen infection, while the roles of other factors still remain untested. The physiological condition of mollusc broodstock has a profound effect on their offspring fitness. Many other factors such as nutrients, pathogens, environment conditions and pollutants could exert considerable influence on the maternal transfer of immunity. The parent molluscs which have encountered an immune stimulation endow their offspring with a trans-generational immune capability to protect them against infections effectively. The knowledge on maternal transfer of immunity and the trans-generational immune effect could provide us with an ideal management strategy of mollusc broodstock to improve the immunity of offspring and to establish a disease-resistant family for a long-term improvement of cultured stocks. PMID:24858027

Wang, Lingling; Yue, Feng; Song, Xiaorui; Song, Linsheng

2015-02-01

253

Wireless Power Transfer  

ScienceCinema

Wireless Power Transfer is an innovative approach using magnetic resonance coupling of air core transformers designed for today's growing plug-in electric vehicle market. This technology can provide a convenient, safe and flexible means to charge electric vehicles under stationary and dynamic conditions. Plug-in Electric Vehicles (PEV) are burdened by the need for cable and plug charger, galvanic isolation of the on-board electronics, bulk and cost of this charger and the large energy storage system (ESS) packs needed. With a system where you have to physically plug in there are a number of occasions where the owner could very well forget to charge the vehicle. For stationary applications (like charging of a PHEV at home), ORNL's innovative wireless power transfer technology adds a convenience factor compared to actually plugging in which will mean that the vehicle will have a full charge every morning. Electric vehicle charging must be safe, compact and efficient in order to be convenient for customers. By reconfiguring the transformer and altering the resonance frequency, energy is transferred to the battery with lower energy losses and with fewer demands on the primary circuit by the rest of the transformer system. The ORNL discovery shows that sufficient power for the battery can be transferred from the primary to secondary circuits without significant energy losses if the operating frequency is set at 50% to 95% of the resonance frequency of the circuit. The electrical power is then transmitted to the chargeable battery, which is electrically coupled to the secondary circuit through the air core transformer. Some advantages include: Reduced energy losses during transfer of energy to the battery; A charge potential that is relatively unaffected by up to 25% misalignment of vehicle; and Other receiving components draw less power from the primary circuit. These advantages allow wireless power technology applications to expand at the workplace and beyond as the demand for EV rises. For vehicles that operate over a fixed route such as busses and shuttle vehicles, Wireless Power Transfer (WPT) means that a smaller battery pack can be used. In the traditional system, the battery pack is designed to accommodate the needs of the entire route or shift. With WPT the battery can be downsized because it can be charged when the vehicle stops on its route (a rental car shuttle bus, for example, can charge when it waits in the terminal and again when it waits at the rental car place. Thus the battery only needs enough charge to get to the next stop. This decrease in battery size means significant cost savings to electrify the vehicle. This technology enables efficient "opportunity charging stations" for predefined routes and planned stops reducing down time. Charging can occur in minutes. This improvement also eliminates the harmful emissions that occur in garages while buses are at idle during charging. In larger cities, dynamic charging offers an even greater impact utilizing existing infrastructure. As vehicles travel along busy freeways and interstate systems, wireless charging can occur while the vehicle is in motion. With this technology a vehicle essentially has unlimited electric range while using a relatively small battery pack. In-motion charging stations use vehicle sensors to alert the driver. Traveling at normal speeds, sensors establish in-motion charging. WPT transmit pads sequentially energize to the negotiated power level based on vehicle speed and its requested charging energy. Lower power when vehicle speed is slow and much higher power for faster moving vehicles. Vehicle to Infrastructure communications (V2I) coordinates WPT charging level according to on-board battery pack state-of-charge. V2I activates the roadway transmit pads placing them in standby mode and negotiates charging fee based on prevailing grid rate and vehicle energy demand. Dynamic charging would allow electricity to supply a very large fraction of the energy for the transportation sector and reduce greatly petroleum consump

None

2013-11-19

254

Wireless Power Transfer  

SciTech Connect

Wireless Power Transfer is an innovative approach using magnetic resonance coupling of air core transformers designed for today's growing plug-in electric vehicle market. This technology can provide a convenient, safe and flexible means to charge electric vehicles under stationary and dynamic conditions. Plug-in Electric Vehicles (PEV) are burdened by the need for cable and plug charger, galvanic isolation of the on-board electronics, bulk and cost of this charger and the large energy storage system (ESS) packs needed. With a system where you have to physically plug in there are a number of occasions where the owner could very well forget to charge the vehicle. For stationary applications (like charging of a PHEV at home), ORNL's innovative wireless power transfer technology adds a convenience factor compared to actually plugging in which will mean that the vehicle will have a full charge every morning. Electric vehicle charging must be safe, compact and efficient in order to be convenient for customers. By reconfiguring the transformer and altering the resonance frequency, energy is transferred to the battery with lower energy losses and with fewer demands on the primary circuit by the rest of the transformer system. The ORNL discovery shows that sufficient power for the battery can be transferred from the primary to secondary circuits without significant energy losses if the operating frequency is set at 50% to 95% of the resonance frequency of the circuit. The electrical power is then transmitted to the chargeable battery, which is electrically coupled to the secondary circuit through the air core transformer. Some advantages include: Reduced energy losses during transfer of energy to the battery; A charge potential that is relatively unaffected by up to 25% misalignment of vehicle; and Other receiving components draw less power from the primary circuit. These advantages allow wireless power technology applications to expand at the workplace and beyond as the demand for EV rises. For vehicles that operate over a fixed route such as busses and shuttle vehicles, Wireless Power Transfer (WPT) means that a smaller battery pack can be used. In the traditional system, the battery pack is designed to accommodate the needs of the entire route or shift. With WPT the battery can be downsized because it can be charged when the vehicle stops on its route (a rental car shuttle bus, for example, can charge when it waits in the terminal and again when it waits at the rental car place. Thus the battery only needs enough charge to get to the next stop. This decrease in battery size means significant cost savings to electrify the vehicle. This technology enables efficient "opportunity charging stations" for predefined routes and planned stops reducing down time. Charging can occur in minutes. This improvement also eliminates the harmful emissions that occur in garages while buses are at idle during charging. In larger cities, dynamic charging offers an even greater impact utilizing existing infrastructure. As vehicles travel along busy freeways and interstate systems, wireless charging can occur while the vehicle is in motion. With this technology a vehicle essentially has unlimited electric range while using a relatively small battery pack. In-motion charging stations use vehicle sensors to alert the driver. Traveling at normal speeds, sensors establish in-motion charging. WPT transmit pads sequentially energize to the negotiated power level based on vehicle speed and its requested charging energy. Lower power when vehicle speed is slow and much higher power for faster moving vehicles. Vehicle to Infrastructure communications (V2I) coordinates WPT charging level according to on-board battery pack state-of-charge. V2I activates the roadway transmit pads placing them in standby mode and negotiates charging fee based on prevailing grid rate and vehicle energy demand. Dynamic charging would allow electricity to supply a very large fraction of the energy for the transportation sector and reduce greatly petroleum consump

None

2013-07-22

255

Electron Transfer versus Proton Transfer in Gas-Phase Ion/Ion Reactions of Polyprotonated Peptides  

PubMed Central

The ion/ion reactions of several dozen reagent anions with triply protonated cations of the model peptide KGAILKGAILR have been examined to evaluate predictions of a Landau–Zener-based model for the likelihood for electron transfer. Evidence for electron transfer was provided by the appearance of fragment ions unique to electron transfer or electron capture dissociation. Proton transfer and electron transfer are competitive processes for any combination of anionic and cationic reactants. For reagent anions in reactions with protonated peptides, proton transfer is usually significantly more exothermic than electron transfer. If charge transfer occurs at relatively long distances, electron transfer should, therefore, be favored on kinetic grounds because the reactant and product channels cross at greater distances, provided conditions are favorable for electron transfer at the crossing point. The results are consistent with a model based on Landau–Zener theory that indicates both thermodynamic and geometric criteria apply for electron transfer involving polyatomic anions. Both the model and the data suggest that electron affinities associated with the anionic reagents greater than about 60–70 kcal/mol minimize the likelihood that electron transfer will be observed. Provided the electron affinity is not too high, the Franck–Condon factors associated with the anion and its corresponding neutral must not be too low. When one or the other of these criteria is not met, proton transfer tends to occur essentially exclusively. Experiments involving ion/ion attachment products also suggest that a significant barrier exists to the isomerization between chemical complexes that, if formed, lead to either proton transfer or electron transfer. PMID:16144411

Gunawardena, Harsha P.; He, Min; Chrisman, Paul A.; Pitteri, Sharon J.; Hogan, Jason M.; Hodges, Brittany D. M.; McLuckey, Scott A.

2005-01-01

256

Phonon-induced dynamic resonance energy transfer  

NASA Astrophysics Data System (ADS)

In a network of interacting quantum systems, achieving fast coherent energy transfer is a challenging task. While quantum systems are susceptible to a wide range of environmental factors, in many physical settings their interactions with quantized vibrations, or phonons, of a supporting structure are the most prevalent. This leads to noise and decoherence in the network, ultimately impacting the energy-transfer process. In this work, we introduce a novel type of coherent energy-transfer mechanism for quantum systems, where phonon interactions are able to actually enhance the energy transfer. Here, a shared phonon interacts with the systems and dynamically adjusts their resonances, providing remarkable directionality combined with quantum speed-up. We call this mechanism phonon-induced dynamic resonance energy transfer and show that it enables long-range coherent energy transport even in highly disordered systems.

Lim, James; Tame, Mark; Yee, Ki Hyuk; Lee, Joong-Sung; Lee, Jinhyoung

2014-05-01

257

HEAT TRANSFER FLUIDS  

E-print Network

The choice of heat transfer fluids has significant effects on the performance, cost, and reliability of solar thermal systems. In this chapter, we evaluate existing heat transfer fluids such as oils and molten salts based ...

Lenert, Andrej

2012-01-01

258

Methods of Heat Transfer  

NSDL National Science Digital Library

To help students better understand conduction, convection, and radiation as methods of heat transfer in solids, liquids and gases. Let's look at all three methods of heat transfer ... Overview of Conduction, Convection, Radiation Conduction- 1. Explain what happens as heat energy is supplied to one part of a solid. 2. Explain how energy is transferred by conduction through a solid. Convection- 1. What is ?anything fluid? ? Include two examples. 2. Describe how and why heat is transferred in ...

Carlone, Mrs.

2006-11-12

259

Spatialized Transfer Functions  

Microsoft Academic Search

Multi-dimensional transfer functions are an efcient way to visualize features in scalar volume data produced by CT or MRI scanners. However, the optimal transfer function is difcult to nd in general. We present an automatic yet powerful method for the automatic setup of multi-dimensional transfer functions by adding spatial information to the histogram of a volume. Using this information we

Stefan Röttger; Michael Bauer; Marc Stamminger

2005-01-01

260

Transfer of Learning.  

ERIC Educational Resources Information Center

This document contains four symposium papers on transfer of learning. In "Learning Transfer in a Social Service Agency: Test of an Expectancy Model of Motivation" (Reid A. Bates) structural equation modeling is used to test the validity of a valence-instrumentality-expectancy approach to motivation to transfer learning. "The Relationship between…

1999

261

Engineering heat transfer  

SciTech Connect

This book consists of eight chapters which cover the following topics: fundamental concepts of heat transfer; the general conduction equation; steady state conduction in one dimension; heat transfer from extended surfaces; steady state conduction in multiple dimensions; unsteady state heat conduction; introduction to convection; and convection heat transfer in a closed conduit. Each chapter includes a summary and problems.

Janna, W.

1986-01-01

262

Transfer of Learning Transformed  

ERIC Educational Resources Information Center

Instruction is motivated by the assumption that students can transfer their learning, or apply what they have learned in school to another setting. A common problem arises when the expected transfer does not take place, what has been referred to as the inert knowledge problem. More than an academic inconvenience, the failure to transfer is a major…

Larsen-Freeman, Diane

2013-01-01

263

Model for Ground-Coupled Heat and Moisture Transfer from Buildings  

SciTech Connect

An important factor in soil heat transfer that is often over looked is the effect of moisture, which can vary the effective thermal conductivity by a factor of ten. The objective of this research was to investigate the ground-coupled heat and moisture transfer from buildings, and to develop results and tools to improve energy simulation of ground-coupled heat transfer.

Deru, M.

2003-06-01

264

Transferability of interventions in health education: a review  

PubMed Central

Background Health education interventions are generally complex. Their outcomes result from both the intervention itself and the context for which they are developed. Thus, when an intervention carried out in one context is reproduced in another, its transferability can be questionable. We performed a literature review to analyze the concept of transferability in the health education field. Methods Articles included were published between 2000 and 2010 that addressed the notion of transferability of interventions in health education. Articles were analyzed using a standardized grid based on four items: 1) terminology used; 2) factors that influenced transferability; 3) capacity of the research and evaluation designs to assess transferability; and 4) tools and criteria available to assess transferability. Results 43 articles met the inclusion criteria. Only 13 of them used the exact term “transferability” and one article gave an explicit definition: the extent to which the measured effectiveness of an applicable intervention could be achieved in another setting. Moreover, this concept was neither clearly used nor distinguished from others, such as applicability. We highlight the levels of influence of transferability and their associated factors, as well as the limitations of research methods in their ability to produce transferable conclusions. Conclusions We have tried to clarify the concept by defining it along three lines that may constitute areas for future research: factors influencing transferability, research methods to produce transferable data, and development of criteria to assess transferability. We conclude this review with three propositions: 1) a conceptual clarification of transferability, especially with reference to other terms used; 2) avenues for developing knowledge on this concept and analyzing the transferability of interventions; and 3) in relation to research, avenues for developing better evaluation methods for assessing the transferability of interventions. PMID:22747988

2012-01-01

265

Heat transfer system  

DOEpatents

A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

McGuire, Joseph C. (Richland, WA)

1982-01-01

266

Heat transfer system  

DOEpatents

A heat transfer system for a nuclear reactor is described. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

Not Available

1980-03-07

267

Adeno-Associated Virus —Mediated Gene Transfer for Hemophilia B  

Microsoft Academic Search

Hemophilia is the bleeding diathesis caused by mutations in the gene encoding factor VIII (hemophilia A) or factor IX (hemophilia\\u000a B). Currently, the disease is treated by intravenous infusion of the missing purified clotting factor. The goal of gene transfer\\u000a for treating hemophilia is to achieve sustained expression of factor VIII or factor IX at levels high enough to improve

Katherine A. High

2002-01-01

268

Factor Trees  

NSDL National Science Digital Library

In this online activity, the learner finds the prime factorization of composite numbers by building factor trees. A second level includes finding the greatest common factor and the least common multiple by sorting factors using a Venn Diagram.

2010-01-01

269

Factor Trees  

NSDL National Science Digital Library

This virtual manipulative allows students to find the prime factorization of numbers by completing factor trees. Then they may use a venn diagram to sort the prime factors to find the greatest common factor and the least common multiple.

Math Playground

2009-07-29

270

Heat transfer enhancement in metal hydride systems  

NASA Astrophysics Data System (ADS)

An attempt has been made to enhance the heat transfer of hydrogen storage metal hydride systems by the addition of small fraction of high conductivity materials in various configurations. Results indicate that the form of the enhancement material rather than its composition is the more critical factor. The addition of over 6% aluminum foam enhances the effective thermal conductivity of a hydride bed by a factor of 2.6.

Rosso, M. J., Jr.; Strickland, G.

271

Transferring learning from faculty development to the classroom.  

PubMed

This study’s purpose was to better understand the transfer of learning by uncovering how various factors supported the integration of health information technology knowledge and skills gleaned from the Health Resources and Services Administration–funded faculty development programs into nursing education curricula. Through interviews with 20 participants from four programs, this study confirmed the importance of findings related to faculty, program, and work environment characteristics for supporting successful transfer of learning and substantiates a variety of other transfer-of-learning research. New or seldom discussed supportive individual characteristics were found, including leadership abilities, lifelong learning, ability to recognize limitations, persistence, creativity, and risk taking. The importance of networking, diversity of perspectives, postconference support, and teams in program designs were found to positively influence transfer. The variety of supportive factors and barriers in the participants’ work environments strengthens the assertions that transfer may be context dependent. Findings provided insight for recommendations to improve learning transfer. PMID:25494191

Rock, Kim Z

2014-12-01

272

Adenoviral Transfer of Murine Oncostatin M Elicits Periosteal Bone Apposition in Knee Joints of Mice, Despite Synovial Inflammation and Up-Regulated Expression of Interleukin-6 and Receptor Activator of Nuclear Factor-?B Ligand  

PubMed Central

Oncostatin M (OSM) has been described as a bone-remodeling factor either stimulating osteoblast activity or osteoclast formation in vitro. To elucidate the in vivo effect of OSM on bone remodeling, we injected an adenoviral vector encoding murine OSM in knee joints of mice. OSM strongly induced interleukin (IL)-6 gene expression, a known mediator of osteoclast development. We investigated the OSM effect in wild-type and IL-6-deficient mice and found a similar degree of OSM-induced joint inflammation. Within the first week of inflammation, the periosteum along the femur and tibia increased in cell number and stained positive for the osteoblast marker alkaline phosphatase. At these sites bone apposition occurred in both strains as demonstrated by Goldner and Von Kossa staining. In vitro OSM enhanced the effect of bone morphogenetic protein-2 on osteoblast differentiation. Immunohistochemistry demonstrated expression of receptor activator of nuclear factor-?B ligand (RANKL) and its receptor, receptor activator of nuclear factor-?B (RANK), in the periosteum but osteoclasts were not detected at sites of bone apposition. Induced mRNA expression for the receptor activator of nuclear factor-?B ligand inhibitor osteoprotegerin probably controlled osteoclast development during OSM overexpression. Our results show that OSM favors bone apposition at periosteal sites instead of resorption in vivo. This effect was not dependent on or inhibited by IL-6. PMID:12000725

de Hooge, Alfons S. K.; van de Loo, Fons A. J.; Bennink, Miranda B.; de Jong, Diana S.; Arntz, Onno J.; Lubberts, Erik; Richards, Carl D.; van den Berg, Wim B.

2002-01-01

273

Wavelet Basis Functions for Precomputed Radiance Transfer  

E-print Network

Precomputed Radiance Transfer (PRT) aims at computing global illu- mination effects such as soft shadows. Several basis function have been proposed for PRT. Recently, Haar wavelets have been employed which functions Fi() -- the lighting, the BRDF and the n dynamic occlusion fields. For PRT, these factors

Toronto, University of

274

Maximizing profits in international technology transfer  

NASA Technical Reports Server (NTRS)

Maximum profit can be introduced into international technology transfer by observing the following: (1) ethical and open dealing between the parties; (2) maximum knowledge of all facts concerning the technology, the use of the technology, the market, competition, prices, and alternatives; (3) ability to coordinate exports, service, support activities, licensing and cross licensing; and (4) knowledgeable people which put these factors together.

Straube, W.

1974-01-01

275

A Method for Evaluating the Knowledge Transfer Ability in Organization  

Microsoft Academic Search

Knowledge transfer as an important aspect of knowledge management has been considered as an effective way to promote the knowledge\\u000a ability and the core competence of an organization. In this paper, a method to evaluate knowledge transfer ability in organization\\u000a is proposed. Firstly, the main factors which affect the knowledge transfer ability to be found out through the analysis of

Tian-hui You; Fei-fei Li; Zhu-chao Yu

2006-01-01

276

The transfer of cesium-137 and strontium-90 from soil to food crops after the Chernobyl accident.  

PubMed

The soil to plant transfer of 137Cs and 90Sr was studied at seven locations in Finland over 4 and 2 years, respectively. The plant/soil concentration ratio of 137Cs for field crops in the southern area (60 degrees-63 degrees N) ranged from 0.001 to 0.26 and in the northern area (64 degrees-67 degrees N) from 0.01 to 2.29, and that of 90 Sr in the whole area from 0.02 to 2.44. The mean concentration ratio of 90Sr was about nine times higher than that of 137Cs in the southern area. The concentration ratio of 137Cs for leaf vegetables fluctuated between years, and that for carrot, potato and especially cereals decreased gradually after the first year. In the fourth year, the mean concentration ratio of 137Cs in the southern area was about 60% of the first year value for coarse mineral soils and 80% of that for clay and silt soils. There was no difference in the average 90Sr ratios between the 2 years studied. The concentration ratio of 137Cs was lower for clay and silt soils than for coarse mineral soils, and the 90Sr ratio was lowest for organic soils. The concentration ratio of 137Cs for vegetables and grain decreased in the order: lettuce, cabbage > carrot, potato > cereals, onion; for fruits in the order: blackcurrant > strawberry > apple, and the concentration ratio of 90Sr decreased in the order: lettuce, cabbage > carrot, onion > cereals > potato. PMID:7973616

Paasikallio, A; Rantavaara, A; Sippola, J

1994-10-14

277

Numerical computation of fluid flow and heat transfer in microchannels  

Microsoft Academic Search

Three-dimensional fluid flow and heat transfer phenomena inside heated microchannels is investigated. The steady, laminar flow and heat transfer equations are solved using a finite-volume method. The numerical procedure is validated by comparing the predicted local thermal resistances with available experimental data. The friction factor is also predicted in this study. It was found that the heat input lowers the

K. C Toh; X. Y Chen; J. C Chai

2002-01-01

278

Local Academic Knowledge Transfers and the Concentration of Economic Activity  

Microsoft Academic Search

In this paper I examine agglomeration effects on the intensity of local knowledge transfers from universities to high technology innovations within the modified Griliches-Jaffe knowledge production function framework. Estimations are carried out at the level of U.S. metropolitan areas. Concentration of high technology employment turns out to be the most important factor promoting local academic knowledge transfers. I find that

Attila Varga

2000-01-01

279

Maternal transfer of antibodies: raising immuno-ecology issues  

Microsoft Academic Search

The transfer of antibodies from mother to offspring has broad potential implications in evolutionary ecology, from the adaptive value of maternal effects to the role of transgenerational plasticity in host-parasite inter- actions. Recent contributions have addressed key issues such as environmental and genetic factors affecting the amount of antibodies transferred and whether maternal antibodies affect offspring immunity, but little is

Thierry Boulinier; Vincent Staszewski

2008-01-01

280

Heat transfer enhancement of copper nanofluid with acoustic cavitation  

Microsoft Academic Search

Heat transfer characteristics of copper nanofluids with and without acoustic cavitation were investigated experimentally. The effects of such factors as acoustical parameters, nanofluid concentration and fluid subcooling on heat transfer enhancement around a heated horizontal copper tube were discussed in detail. The results indicated that the copper nanoparticles and acoustic cavitation had profound and significant influence on heat transport in

D. W. Zhou

2004-01-01

281

Multidirectional Wear and Transfer Film Formation in Polyetheretherketone  

E-print Network

multidirectional pin-on-plate wear study of PEEK was conducted with a focus on molecular weight and sliding path directionality. These factors were studied for their correlation to overall wear performance. Additionally, transfer film thickness was measured...

Laux, Kevin

2012-07-16

282

10 CFR 626.7 - Royalty transfer and exchange.  

Code of Federal Regulations, 2010 CFR

...REGULATION PROCEDURES FOR ACQUISITION OF PETROLEUM FOR THE STRATEGIC PETROLEUM RESERVE § 626.7 Royalty transfer and exchange...capability, logistical problems for moving petroleum products, macroeconomic factors, and...

2010-01-01

283

10 CFR 626.7 - Royalty transfer and exchange.  

Code of Federal Regulations, 2012 CFR

...REGULATION PROCEDURES FOR ACQUISITION OF PETROLEUM FOR THE STRATEGIC PETROLEUM RESERVE § 626.7 Royalty transfer and exchange...capability, logistical problems for moving petroleum products, macroeconomic factors, and...

2012-01-01

284

10 CFR 626.7 - Royalty transfer and exchange.  

Code of Federal Regulations, 2011 CFR

...REGULATION PROCEDURES FOR ACQUISITION OF PETROLEUM FOR THE STRATEGIC PETROLEUM RESERVE § 626.7 Royalty transfer and exchange...capability, logistical problems for moving petroleum products, macroeconomic factors, and...

2011-01-01

285

10 CFR 626.7 - Royalty transfer and exchange.  

Code of Federal Regulations, 2013 CFR

...REGULATION PROCEDURES FOR ACQUISITION OF PETROLEUM FOR THE STRATEGIC PETROLEUM RESERVE § 626.7 Royalty transfer and exchange...capability, logistical problems for moving petroleum products, macroeconomic factors, and...

2013-01-01

286

Elongation Factor Tu and DnaK Are Transferred from the Cytoplasm to the Periplasm of Escherichia coli during Osmotic Downshock Presumably via the Mechanosensitive Channel MscL  

Microsoft Academic Search

Upon osmotic downshock, a few cytoplasmic proteins, including thioredoxin, elongation factor Tu (EF-Tu), and DnaK, are released from Tris-EDTA-treated Escherichia coli cells by an unknown mechanism. We have shown previously that deletion of mscL, the gene coding for the mechanosensitive channel of the plasma membrane with the highest conductance, prevents the release of thioredoxin. We confirm and extend the implication

CATHERINE BERRIER; ALEXIA GARRIGUES; GILBERT RICHARME; ALEXANDRE GHAZI

2000-01-01

287

Automatic microbial transfer  

NASA Technical Reports Server (NTRS)

Device can transfer metabolites or inhibitory agents to broth cultures of bacteria, in various stages of growth, for study. It also has application in transfer of other micro-organisms, such as yeasts, and could be useful in clinical and research laboratories. Device has been used for wide variety of purposes in experimental situations.

Wilkins, J. R.; Mills, S. M.

1973-01-01

288

Transfer Study Data.  

ERIC Educational Resources Information Center

Longitudinal data are presented relating to Bakersfield College (BC) students who transferred to public four-year colleges and universities. Highlighted findings include the following: (1) first-time transfers from BC to the California State University and College (CSUC) system increased by 5.7% from fall 1984 to fall 1985, continuing a gradual…

Scott, David C.

289

Transfer Study Data.  

ERIC Educational Resources Information Center

Longitudinal data are presented relating to Bakersfield College (BC) students who transferred to public four-year colleges and universities. Highlighted findings include the following: (1) first-time transfers from BC to the California State University and College (CSUC) system increased by 19.4% from fall 1987 to fall 1988, the highest since the…

Scott, David

290

International Student Advisor's Transfer Report (Transfer to Texas Tech University)  

E-print Network

International Student Advisor's Transfer Report (Transfer to Texas Tech University) Section One (to: _______________________ Semester Last Attended ________ Semester intended to transfer to Texas Tech University: Fall _____ Spring Tech University. Student's Signature __________________________ Date

Rock, Chris

291

Load transfer approach for laterally loaded piles  

NASA Astrophysics Data System (ADS)

A two-parameter model has been proposed previously for predicting the response of laterally loaded single piles in homogenous soil. A disadvantage of the model is that at high Poisson's ratio, unreliable results may be obtained. In this paper, a new load transfer approach is developed to simulate the response of laterally loaded single piles embedded in a homogeneous medium, by introducing a rational stress field. The approach can overcome the inherent disadvantage of the two-parameter model, although developed in a similar way. Generalized solutions for a single pile and the surrounding soil under various pile-head and base conditions were established and presented in compact forms. With the solutions, a load transfer factor, correlating the displacements of the pile and the soil, was estimated and expressed as a simple equation. Expressions were developed for the modulus of subgrade reaction for a Winkler model as a unique function of the load transfer factor. Simple expressions were developed for estimating critical pile length, maximum bending moment, and the depth at which the maximum moment occurs. All the newly established solutions and/or expressions, using the load transfer factor, offer satisfactory predictions in comparison with the available, more rigorous numerical approaches. The current solutions are applicable to various boundary conditions, and any pile-soil relative stiffness.

Guo, Wei Dong; Lee, F. H.

2001-09-01

292

Numerical Radiative Transfer  

NASA Astrophysics Data System (ADS)

Preface; Introduction; Part I. Operator Perturbation: 1. Survey of operator perturbation methods W. Kalkofen; 2. Line formation in expanding atmospheres: multilevel calculations using approximate lambda operators W. R. Hamann; 3. Stellar atmospheres in non-LTE: model construction and line formation calculations using approximate lambda operators K. Werner; 4. Acceleration of convergence L. H. Auer; 5. Line formation in a time-dependent atmosphere W. Kalkofen; 6. Iterative solution of multilevel transfer problems Eugene H. Avrett and Rudolf Loeser; 7. An algorithm for the simultaneous solution of thousands of transfer equations under global constraints Lawrence S. Anderson; 8. Operator perturbation for differential equations W. Kalkofen; Part II. Polarised Radiation: 9. A gentle introduction to polarised radiative transfer David E. Rees; 10. Non-LTE polarised radiative transfer in special lines David E. Rees and Graham A. Murphy; 11. Transfer of polarised radiation using 4x4 matrices E. Landi Degli'Innocenti; 12. Radiative transfer in the presence of strong magnetic fields A. A. van Ballegooijen; 13. An integral operator technique of radiative transfer in spherical symmetry A. Peraiah; 14. Discrete ordinate matrix method M. Schmidt and R. Wehrse.

Kalkofen, Wolfgang

2009-07-01

293

Nova-induced mass transfer variations  

E-print Network

We investigate variations of the mass transfer rate in cataclysmic variables (CVs) that are induced by nova outbursts. The ejection of nova shells leads to a spread of transfer rates in systems with similar orbital period. The effect is maximal if the specific angular momentum in the shell is the same as the specific orbital angular momentum of the white dwarf. We show analytically that in this case the nova-induced widening of the mass transfer rate distribution can be significant if the system, in the absence of nova outbursts, is close to mass transfer instability (i.e., within a factor of ~1.5 of the critical mass ratio). Hence the effect is negligible below the period gap and for systems with high-mass white dwarfs. At orbital periods between about 3 and 6 hrs the width of the mass transfer rate distribution exceeds an order of magnitude if the mass accreted on the white dwarf prior to the runaway is larger than a few 10^{-4} M_sun. At a given orbital period in this range, systems with the highest transfer rate should on average have the largest ratio of donor to white dwarf mass. We show results of population synthesis models which confirm and augment the analytic results.

Ulrich Kolb; Saul Rappaport; Klaus Schenker; Steve Howell

2001-08-20

294

Heat transfer in pipes  

NASA Technical Reports Server (NTRS)

The heat transfer from hot water to a cold copper pipe in laminar and turbulent flow condition is determined. The mean flow through velocity in the pipe, relative test length and initial temperature in the vessel were varied extensively during tests. Measurements confirm Nusselt's theory for large test lengths in laminar range. A new equation is derived for heat transfer for large starting lengths which agrees satisfactorily with measurements for large starting lengths. Test results are compared with the new Prandtl equation for heat transfer and correlated well. Test material for 200- and to 400-diameter test length is represented at four different vessel temperatures.

Burbach, T.

1985-01-01

295

Investment casting heat transfer  

NSDL National Science Digital Library

Calculate temperature profile and Biot number in mixed conduction and convection/radiation heat transfer from liquid metal through a ceramic mold to the environment, and suggest a design change to reduce the probability of shattering due to thermal stress.

Powell, Adam C., IV

2004-12-15

296

FLT Transfer Agreement  

Cancer.gov

Provider: National Cancer Institute (NCI) Provider agrees to transfer to Recipient the following Production Documents (click here) for the production of 3'-deoxy-3'- [F-18] fluorothymidine ([F-18] FLT). (A) Generic Chemistry, Manufacturing and Control

297

Smoothness- transferred random field  

E-print Network

We propose a new random field (RF) model, smoothness-transfer random field (ST-RF) model, for image modeling. In the objective function of RF models, smoothness energy is defined with compatibility function to capture the ...

Wei, Donglai

2013-01-01

298

Transfer Log.xls  

Cancer.gov

ANIMAL TRANSFER LOG Date of Move: ________________ Cage Type C = Auto Water NOTES: B = Water Bottle S = SMZ M = Microisolator ASP # PI GROUP NAME # CAGES [+] ROOM TO DOB COMMENTS STRAIN CODE NEW GROUP NAME NEW ROOM CAGE TYPE PEDIGREE # EAR

299

DCIDE Material Transfer Agreement  

Cancer.gov

MATERIAL TRANSFER AGREEMENT The National Cancer Institute (NCI) Development of Clinical Imaging Drugs and Enhancers Program (DCIDE) has been designed to assist academic and business investigators to acquire the data necessary for them to file an Investigational

300

Condensation heat transfer  

NASA Astrophysics Data System (ADS)

The paper gives a brief description of some of the better understood aspects of condensation heat transfer and includes discussion of the liquid-vapour interface, natural and forced convection laminar film condensation and dropwise condensation.

Rose, J. W.

301

Technology transfer for adaptation  

NASA Astrophysics Data System (ADS)

Technology alone will not be able to solve adaptation challenges, but it is likely to play an important role. As a result of the role of technology in adaptation and the importance of international collaboration for climate change, technology transfer for adaptation is a critical but understudied issue. Through an analysis of Global Environment Facility-managed adaptation projects, we find there is significantly more technology transfer occurring in adaptation projects than might be expected given the pessimistic rhetoric surrounding technology transfer for adaptation. Most projects focused on demonstration and early deployment/niche formation for existing technologies rather than earlier stages of innovation, which is understandable considering the pilot nature of the projects. Key challenges for the transfer process, including technology selection and appropriateness under climate change, markets and access to technology, and diffusion strategies are discussed in more detail.

Biagini, Bonizella; Kuhl, Laura; Gallagher, Kelly Sims; Ortiz, Claudia

2014-09-01

302

Closed transfer systems  

SciTech Connect

The handling of concentrated pesticides presents the greatest chance of exposure to the handler. A recent study shows that approximately 90% of the total chemical exposure is to the mixer/loader, while the applicator receives the remaining 10%. A closed transfer system is an excellent way of limiting exposure to the handler. This is especially important when the handler does not wear the personal protective equipment as recommended on the chemical label. There are several types of closed transfer systems commercially available. The vacuum type is safer as compared to a pressure system. If a leak occurs in the vacuum system, air will be pulled in versus chemical squirting out. Many closed transfer systems incorporate pressure rinsing of one-way pesticide containers. This helps reduce the chance of exposure as the rinsate is transferred to the spray tank through the handling system.

Hofman, V. [North Dakota State Univ., Fargo, ND (United States)

1994-12-31

303

Ames Lab 101: Technology Transfer  

ScienceCinema

Ames Laboratory Associate Laboratory Director, Sponsored Research Administration, Debra Covey discusses technology transfer. Covey also discusses Ames Laboratory's most successful transfer, lead-free solder.

Covey, Debra

2012-08-29

304

Practical Oblivious Transfer Protocols  

Microsoft Academic Search

We consider 1-out-N Oblivious Transfer (OT) for strings. Oblivious Transfer is a primitive used in a variety of cryptographic protocols and applications\\u000a (e.g. [11], 1, 10, 17, 12, [13]).\\u000a \\u000a We present a new highly efficient two-pass (one-round) protocol for 1- out-N OT. Our protocol has a constant online computational complexity (for the chooser as well as for the sender). This

Christian Tobias; Justus Liebig

2002-01-01

305

Oxygen transfer in liquids.  

PubMed

In the laboratory-type airlift tower reactor oxygen transfer from air in tap water and/or polyacrylamide solutions (Neuperm WF) was studied. In order to characterize the system, volumetric coefficient of oxygen transfer was determined by the gassing-out method. Two arrangements of the airlift tower reactor were compared, namely the reactor with and without motionless mixer. In addition, mean relative gas holdup and gas power output were determined for both arrangements. PMID:18553699

Stejskal, J; Pot?cek, F

1985-04-01

306

Luminescence resonance energy transfer  

Microsoft Academic Search

Fluorescence resonance energy transfer (FRET), in which a fluorescent donor molecule transfers energy via a nonradiative dipole-dipole interaction to an acceptor molecule (which is usually a fluorescent molecule), is a standard spectroscopic technique for measuring distances in the 10-70 Angstrom range. We have used a luminescent europium chelate as donor and an organic dye, CY-5, as acceptor. This luminescence resonance

Paul R. Selvin; Tariq M. Rana; John E. Hearst

1994-01-01

307

Radiant-interchange Configuration Factors  

NASA Technical Reports Server (NTRS)

A study is presented of the geometric configuration factors required for computing radiant heat transfer between opaque surfaces separated by a nonabsorbing medium and various methods of determining the configuration factors are discussed. Configuration-factor solutions available in the literature have been checked and the more complicated equations are presented as families of curves. Cases for point, line, and finite-area sources are worked out over a wide range of geometric proportions. These cases include several new configurations involving rectangles, triangles, and cylinders of finite length which are integrated and tabulated. An analysis is presented, in which configuration factors are employed of the radiant heat transfer to the rotor blades of a typical gas turbine under different conditions of temperature and pressure. (author)

Hamilton, D C :; Morgan, W R

1952-01-01

308

The neutrino charge form-factor  

NASA Technical Reports Server (NTRS)

Mathematical analysis and dispersion relations are used to obtain the general functional form of the neutrino charge form-factor. It is shown that if the scale for weak interactions is given by G, where G is the Fermi coupling constant, then for a large range of momentum transfer values, the form-factor may be approximated by a function that is linear in the square of the momentum transfer.

Mickens, R. E.

1975-01-01

309

FACTORS INFLUENCING TOTAL DIETARY EXPOSURE OF YOUNG CHILDREN  

EPA Science Inventory

A deterministic model was developed to identify critical input parameters to assess dietary intake of young children. The model was used as a framework for understanding important factors in data collection and analysis. Factors incorporated included transfer efficiencies of pest...

310

Goals, Family, and Community: What Drives Tribal College Transfer Student Success  

ERIC Educational Resources Information Center

This article examines success factors for American Indian tribal college students who transfer to 4-year predominantly White institutions. The study examined the experiences of 8 tribal college transfer students to Midwest universities. Using an indigenous methodology, 3 themes were found to help American Indian tribal college transfer students…

Makomenaw, Matthew

2014-01-01

311

Transfer Readiness: A Case Study of Former Santa Monica College Students.  

ERIC Educational Resources Information Center

Addresses the motivating factors that led to research and collaboration efforts to uncover issues pertaining to transfer students at Santa Monica College (SMC) (California). Reports on SMC's five-year research project, which involved querying transfer students about their experience. The answers helped SMC adjust its curriculum, modify transfer…

Johnson-Benson, Brenda; Geltner, Peter B.; Steinberg, Steven K.

2001-01-01

312

Academic Performance of Howard Community College Students in Transfer Institutions: Preliminary Findings. Research Report Number 37.  

ERIC Educational Resources Information Center

A study was conducted at Howard Community College (HCC) to determine the performance of HCC students at transfer institutions. Four factors related to transfer success were examined: earning an associate degree at HCC; enrolling in a community college transfer program; length of time spent at HCC; and academic preparation and achievement at the…

Radcliffe, Susan K.

313

Health factors in colostrum.  

PubMed

Colostrum is a breast milk produced after the birth of the newborn and lasts for 2-4 days. Colostrum is very important part of breast milk and lays down the immune system and confers growth factors and other protective factors for the young ones in mammals. This is the source of passive immunity achieved by the mother and is transferred to the baby. This is the major source of secretory IgA and gives protection against gastrointestinal infections. In view of so many health factors through colostrum, the use of colostrum has been extended to so many health problems of mankind. Human and bovine colostrums have many similarities barring that bovine colostrum can be obtained in large quantity, so bovine colostrum has been used in various disorders in human beings. This is the nature's gift that is for the young ones to grow as well as for the treatment of many health problems in older age group. PMID:16077241

Thapa, B R

2005-07-01

314

The For-Profit Transfer Path: A Comparison of California Community College Transfer Students  

ERIC Educational Resources Information Center

The results of this study determined that community college students who transfer to for-profit institutions are indeed different from students who follow traditional routes defined as public and non-profit institutions. This study compares the demographic characteristics, academic experiences, and socioeconomic factors of California community…

van Ommeren, Alice

2011-01-01

315

Consulting as a Strategy for Knowledge Transfer  

PubMed Central

Academic researchers who work on health policy and health services are expected to transfer knowledge to decision makers. Decision makers often do not, however, regard academics’ traditional ways of doing research and disseminating their findings as relevant or useful. This article argues that consulting can be a strategy for transferring knowledge between researchers and decision makers and is effective at promoting the “enlightenment” and “interactive” models of knowledge use. Based on three case studies, it develops a model of knowledge transfer–focused consulting that consists of six stages and four types of work. Finally, the article explores how knowledge is generated in consulting and identifies several classes of factors facilitating its use by decision makers. PMID:15960773

Jacobson, Nora; Butterill, Dale; Goering, Paula

2005-01-01

316

Ex vivo nerve growth factor gene transfer to the basal forebrain in presymptomatic middle-aged rats prevents the development of cholinergic neuron atrophy and cognitive impairment during aging.  

PubMed

Nerve growth factor (NGF) is able to restore spatial learning and reverse forebrain cholinergic neuron atrophy when administered intracerebrally to behaviorally impaired aged rats. In the present study, behaviorally unimpaired, middle-aged rats (14-16 months old) received transplants of ex vivo transduced, clonal NGF-secreting immortalized neural progenitor cells, bilaterally in the nucleus basalis and septum. During the subsequent 9 months the aged control animals developed the expected impairment in spatial learning in the water maze task, whereas the animals with NGF-secreting grafts maintained a performance level not different from the 12-month-old control rats. The marked age-induced atrophy (-25%) of the cholinergic neurons in medial septum and nucleus basalis, seen in the aged control rats, was not present in the NGF-treated aged animals. 3H-labeled thymidine autoradiography showed that the transduced cells survived well and had become integrated into the host tissue surrounding the injection sites, and reverse transcription-PCR analysis revealed expression of the NGF transgene, at both 4 and 9 months postgrafting, in the grafted tissue. The results show that long-term supply of NGF from ex vivo transduced immortalized neural progenitor cells locally within the nucleus basalis and septum can prevent the subsequent development of age-dependent neuronal atrophy and behavioral impairments when the animals reach advanced age. PMID:9465107

Martínez-Serrano, A; Björklund, A

1998-02-17

317

Model wall and recovery temperature effects on experimental heat transfer data analysis  

NASA Technical Reports Server (NTRS)

Basic analytical procedures are used to illustrate, both qualitatively and quantitatively, the relative impact upon heat transfer data analysis of certain factors which may affect the accuracy of experimental heat transfer data. Inaccurate knowledge of adiabatic wall conditions results in a corresponding inaccuracy in the measured heat transfer coefficient. The magnitude of the resulting error is extreme for data obtained at wall temperatures approaching the adiabatic condition. High model wall temperatures and wall temperature gradients affect the level and distribution of heat transfer to an experimental model. The significance of each of these factors is examined and its impact upon heat transfer data analysis is assessed.

Throckmorton, D. A.; Stone, D. R.

1974-01-01

318

Luminescence resonance energy transfer  

SciTech Connect

Fluorescence resonance energy transfer (FRET), in which a fluorescent donor molecule transfers energy via a nonradiative dipole-dipole interaction to an acceptor molecule (which is usually a fluorescent molecule), is a standard spectroscopic technique for measuring distances in the 10-70 Angstrom range. We have used a luminescent europium chelate as donor and an organic dye, CY-5, as acceptor. This luminescence resonance energy transfer (LRET) has several advantages over the more conventional FRET. The distance at which 50% of the energy is transferred (R[sub 0]) is large, 70 [angstrom]; the donor lifetime is single exponential and long (0.63 ms in H[sub 2]O; 2.5 ms in D[sub 2]O), making lifetime measurements facile and highly accurate; the orientation dependence (k[sup 2]) of energy transfer is minimized by the donor's multiple electronic transitions and long lifetime, limiting uncertainty in the measured distance due to orientation effects to [+-]12% in the worst case; the sensitized emission of the acceptor can be measured with little or no interfering background, yielding a >50-fold improvement in signal to background over standard donor-acceptor pairs and enabling distances several times R[sub 0] to be measured. 13 refs., 4 figs.

Selvin, P.R.; Rana, T.M.; Hearst, J.E. (Univ. of California, Berkeley, CA (United States) Lawrence Berkeley Lab., CA (United States))

1994-06-29

319

Direct transfer of graphene onto flexible substrates.  

PubMed

In this paper we explore the direct transfer via lamination of chemical vapor deposition graphene onto different flexible substrates. The transfer method investigated here is fast, simple, and does not require an intermediate transfer membrane, such as polymethylmethacrylate, which needs to be removed afterward. Various substrates of general interest in research and industry were studied in this work, including polytetrafluoroethylene filter membranes, PVC, cellulose nitrate/cellulose acetate filter membranes, polycarbonate, paraffin, polyethylene terephthalate, paper, and cloth. By comparing the properties of these substrates, two critical factors to ensure a successful transfer on bare substrates were identified: the substrate's hydrophobicity and good contact between the substrate and graphene. For substrates that do not satisfy those requirements, polymethylmethacrylate can be used as a surface modifier or glue to ensure successful transfer. Our results can be applied to facilitate current processes and open up directions for applications of chemical vapor deposition graphene on flexible substrates. A broad range of applications can be envisioned, including fabrication of graphene devices for opto/organic electronics, graphene membranes for gas/liquid separation, and ubiquitous electronics with graphene. PMID:24127582

Martins, Luiz G P; Song, Yi; Zeng, Tingying; Dresselhaus, Mildred S; Kong, Jing; Araujo, Paulo T

2013-10-29

320

Direct transfer of graphene onto flexible substrates  

PubMed Central

In this paper we explore the direct transfer via lamination of chemical vapor deposition graphene onto different flexible substrates. The transfer method investigated here is fast, simple, and does not require an intermediate transfer membrane, such as polymethylmethacrylate, which needs to be removed afterward. Various substrates of general interest in research and industry were studied in this work, including polytetrafluoroethylene filter membranes, PVC, cellulose nitrate/cellulose acetate filter membranes, polycarbonate, paraffin, polyethylene terephthalate, paper, and cloth. By comparing the properties of these substrates, two critical factors to ensure a successful transfer on bare substrates were identified: the substrate’s hydrophobicity and good contact between the substrate and graphene. For substrates that do not satisfy those requirements, polymethylmethacrylate can be used as a surface modifier or glue to ensure successful transfer. Our results can be applied to facilitate current processes and open up directions for applications of chemical vapor deposition graphene on flexible substrates. A broad range of applications can be envisioned, including fabrication of graphene devices for opto/organic electronics, graphene membranes for gas/liquid separation, and ubiquitous electronics with graphene. PMID:24127582

Martins, Luiz G. P.; Song, Yi; Zeng, Tingying; Dresselhaus, Mildred S.; Kong, Jing; Araujo, Paulo T.

2013-01-01

321

Energy transfer in plasmonic systems  

NASA Astrophysics Data System (ADS)

We present our results on energy transfer between donor and acceptor molecules or quantum dots near a plasmonic nanoparticle. In such systems, the Förster resonance energy transfer is strongly modified due to plasmon-mediated coupling between donors and acceptors. The transfer efficiency is determined by a competition between transfer, radiation and dissipation that depends sensitively on system parameters. When donor and accepror spectral bands overlap with dipole surface plasmon resonance, the dominant transfer mechanism is through plasmon-enhanced radiative coupling. When transfer takes place from an ensemble of donors to an acceptor, a cooperative amplification of energy transfer takes place in a wide range of system parameters.

Pustovit, Vitaliy N.; Urbas, Augustine M.; Shahbazyan, Tigran V.

2014-11-01

322

The role of the University Licensing Office in transferring intellectual property to industry  

NASA Technical Reports Server (NTRS)

Universities in the US have a significant impact on business through the transfer of technology. This transfer of technology takes various forms, including faculty communications, faculty consulting activities, and the direct transfer of technology through the licensing of patents, copyrights, and other intellectual property to industry. The topics discussed include the following: background of the MIT Technology Licensing Office (TLO), goals of the MIT TLO, MIT's technology transfer philosophy, and important factors for success in new company formation.

Preston, John T.

1992-01-01

323

Tech transfer outreach  

SciTech Connect

This document provides an informal summary of the conference workshop sessions. Tech Transfer Outreach '' was originally designed as an opportunity for national laboratory communications and technology transfer staff to become better acquainted and to discuss matters of mutual interest. When DOE field office personnel asked if they could attend, and then when one of our keynote speakers became a participant in the discussions, the actual event grew in importance. The conference participants--the laboratories and DOE representatives from across the nation--worked to brainstorm ideas. Their objective: identify ways to cooperate for effective (and cost-effective) technology transfer outreach. Thus, this proceedings is truly a product of ten national laboratories and DOE, working together. It candidly presents the discussion of issues and the ideas generated by each working group. The issues and recommendations are a consensus of their views.

Liebetrau, S. (ed.)

1992-01-01

324

Transferring Technology to Industry  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the technology transfer processes in which JPL has been involved to assist in transferring the technology derived from aerospace research and development to industry. California Institute of Technology (CalTech), the organization that runs JPL, is the leading institute in patents for all U.S. universities. There are several mechanisms that are available to JPL to inform industry of these technological advances: (1) a dedicated organization at JPL, National Space Technology Applications (NSTA), (2) Tech Brief Magazine, (3) Spinoff magazine, and (4) JPL publications. There have also been many start-up organizations and businesses from CalTech.

Wolfenbarger, J. Ken

2006-01-01

325

Multipurpose Cargo Transfer Bag  

NASA Technical Reports Server (NTRS)

The Logistics Reduction (LR) project within the Advanced Exploration Systems (AES) program is tasked with reducing logistical mass and repurposing logistical items. Multipurpose Cargo Transfer Bags (MCTB) have been designed such that they can serve the same purpose as a Cargo Transfer Bag, the suitcase-shaped common logistics carrying bag for Shuttle and the International Space Station. After use as a cargo carrier, a regular CTB becomes trash, whereas the MCTB can be unzipped, unsnapped, and unfolded to be reused. Reuse ideas that have been investigated include partitions, crew quarters, solar radiation storm shelters, acoustic blankets, and forward osmosis water processing.

Broyan, James; Baccus, Shelley

2014-01-01

326

Sandro Rusconi Gene transfer  

E-print Network

Sandro Rusconi UNIFR Rusconi 2003 Gene transfer: limits and potential as doping vehicle Geneva 30.09.03 AISTS 'genes & sport' workshop 1972-75 Primary school teacher (Locarno, Switzerland) 1975-79 Graduation medicine' & molecular doping: applications and problems, Gene-based doping applications, comparison

Málaga, Universidad de

327

Sandro Rusconi Gene transfer  

E-print Network

Sandro Rusconi aaaaaa UNIFR Rusconi 2003 Gene transfer: limits and potential as doping vehicle Geneva 30.09.03 AISTS 'genes & sport' workshop 1972-75 Primary school teacher (Locarno, Switzerland) 1975 on 'molecular medicine' & molecular doping: applications and problems, Gene-based doping applications

Málaga, Universidad de

328

Horizontal Gene Transfer  

NSDL National Science Digital Library

This Citizendium article offers a comprehensive review of horizontal gene transfer (HGT). Topics include main features of HGT in nature, HGT in prokaryotes, HGT in eukaryotes, history and discovery of HGT, and decoding the tree of life from genomes scrambled by HGT. The image-rich text includes a list of related articles, a bibliography and external links of interest.

Citizendium

329

Transfer to UC.  

ERIC Educational Resources Information Center

This student informational booklet reports that more than 11,000 students transferred from California community colleges to the University of California (UC) in 2000. The publication also answers frequently asked questions. There are three ways to become eligible to attend UC: (1) meet the requirements upon graduating from high school; (2) make up…

California Community Colleges, Sacramento.

330

FMISO Transfer Agreement  

Cancer.gov

Provider: National Cancer Institute (NCI) Provider agrees to transfer to Recipient the following FMISO Production Documents (click here) for the production of [18F]Fluoromisonidazole, 1H-1-(3-[18f]-Fluoro-2-Hydroxy-Propyl)-2-Nitro-Imidazole, [18F]FMISO.

331

FES Transfer Agreement  

Cancer.gov

Provider: National Cancer Institute (NCI) Provider agrees to transfer to Recipient the following FES Production Documents (click here) for the production of [16-[18F]-fluoro-17-estradiol, [18F]FES (A) Generic Chemistry, Manufacturing and Control Section(B)

332

Mass transfer andMass transfer and Mass transfer andMass transfer and  

E-print Network

- kemiteknik - Värme- och strömningssteknik Biskopsgatan 8, 20500 �bo 1/24 6.16.1 ForcedForced for mass transfer with convection: I l f d fl d b (l b l )­ Internal forced flow: inside a tube (laminar or turbulent) ­ External forced flow: around an obstacle (laminar or turbulent) ­ Natural convection Ro

Zevenhoven, Ron

333

Feed tank transfer requirements  

SciTech Connect

This document presents a definition of tank turnover; DOE responsibilities; TWRS DST permitting requirements; TWRS Authorization Basis (AB) requirements; TWRS AP Tank Farm operational requirements; unreviewed safety question (USQ) requirements; records and reporting requirements, and documentation which will require revision in support of transferring a DST in AP Tank Farm to a privatization contractor for use during Phase 1B.

Freeman-Pollard, J.R.

1998-09-16

334

Technology transfer within the government  

NASA Technical Reports Server (NTRS)

The report of a workshop panel concerned with technology transfer within the government is presented. The suggested subtopics for the panel were as follows: (1) transfer from non-NASA U.S. government technology developers to NASA space missions/programs; and (2) transfer from NASA to other U.S. government civil space mission programs. Two presentations were made to the panel: Roles/Value of Early Strategic Planning Within the Space Exploration Initiative (SEI) to Facilitate Later Technology Transfer To and From Industry; and NOAA Satellite Programs and Technology Requirements. The panel discussion addresses the following major issues: DOD/NASA cooperation; alternative mechanisms for interagency communication and interactions; current technology transfer relationships among federal research agencies, and strategies for improving this transfer; technology transfer mechanisms appropriate to intragovernment transfer; the importance of industry as a technology transfer conduit; and measures of merit.

Christensen, Carissa Bryce

1992-01-01

335

Cryogenic Fluid Transfer for Exploration  

NASA Technical Reports Server (NTRS)

This paper discusses current plans and issues for exploration that involve the use of cryogenic transfer. The benefits of cryogenic transfer to exploration missions are examined. The current state of the art of transfer technology is reviewed. Mission concepts of operation for exploration are presented, and used to qualitatively discuss the performance benefits of transfer. The paper looks at the challenges faced to implement a cryogenic transfer system and suggest approaches to address them with advanced development research. Transfer rates required for exploration are shown to have already been achieved in ground test. Cost effective approaches to the required on-orbit demonstration are suggested.

Chato, David J.

2007-01-01

336

Factor Findings  

NSDL National Science Digital Library

In this lesson, students first create factor posters for a variety of different numbers that will be displayed in the classroom to be utilized as a resource throughout the school year. They make discoveries about factors using color tiles, represent their discoveries using graph paper, and display their information on poster board as find factors of an assigned number. The plan includes a list of materials, questions, assessment options, and extensions.

Piecora, Jamie

2000-01-01

337

SEVIS TRANSFER RELEASE FORM (Transfer from Texas Tech University)  

E-print Network

SEVIS TRANSFER RELEASE FORM (Transfer from Texas Tech University) Date: _________________ 1. Name: _______________________________________________________________ Family name First name Middle initial 2. Texas Tech Student ID number school? _______ NOTE TO STUDENT: Once the SEVIS record release date passes, Texas Tech University

Rock, Chris

338

Phenomenology of the Deuteron Electromagnetic Form Factors  

E-print Network

A rigorous extraction of the deuteron charge form factors from tensor polarization data in elastic electron-deuteron scattering, at given values of the 4-momentum transfer, is presented. Then the world data for elastic electron-deuteron scattering is used to parameterize, in three different ways, the three electromagnetic form factors of the deuteron in the 4-momentum transfer range 0-7 fm^-1. This procedure is made possible with the advent of recent polarization measurements. The parameterizations allow a phenomenological characterization of the deuteron electromagnetic structure. They can be used to remove ambiguities in the form factors extraction from future polarization data.

TheJLAB t20 collaboration; D. Abbott

2000-02-04

339

Training transfer: scientific background and insights for practical application.  

PubMed

Training transfer as an enduring, multilateral, and practically important problem encompasses a large body of research findings and experience, which characterize the process by which improving performance in certain exercises/tasks can affect the performance in alternative exercises or motor tasks. This problem is of paramount importance for the theory of training and for all aspects of its application in practice. Ultimately, training transfer determines how useful or useless each given exercise is for the targeted athletic performance. The methodological background of training transfer encompasses basic concepts related to transfer modality, i.e., positive, neutral, and negative; the generalization of training responses and their persistence over time; factors affecting training transfer such as personality, motivation, social environment, etc. Training transfer in sport is clearly differentiated with regard to the enhancement of motor skills and the development of motor abilities. The studies of bilateral skill transfer have shown cross-transfer effects following one-limb training associated with neural adaptations at cortical, subcortical, spinal, and segmental levels. Implementation of advanced sport technologies such as motor imagery, biofeedback, and exercising in artificial environments can facilitate and reinforce training transfer from appropriate motor tasks to targeted athletic performance. Training transfer of motor abilities has been studied with regard to contralateral effects following one limb training, cross-transfer induced by arm or leg training, the impact of strength/power training on the preparedness of endurance athletes, and the impact of endurance workloads on strength/power performance. The extensive research findings characterizing the interactions of these workloads have shown positive transfer, or its absence, depending on whether the combinations conform to sport-specific demands and physiological adaptations. Finally, cross-training as a form of concurrent exercising in different athletic disciplines has been examined in reference to the enhancement of general fitness, the preparation of recreational athletes, and the preparation of athletes for multi-sport activities such as triathlon, duathlon, etc. PMID:23633165

Issurin, Vladimir B

2013-08-01

340

Factor Game  

NSDL National Science Digital Library

This is an interactive applet game exercises a student's factoring ability. A student can play against the computer or against a friend on grids containing the numbers 1-30, 1-49, or 1-100. Each player in turn chooses a number from the board, and then the opponent claims all of its remaining proper factors. A player's score is the sum of all the numbers and factors she/he has chosen. When there are no numbers remaining with unclaimed factors, the game ends and the player with the greater total is the winner.

Adapted with permission from "Prime Time: Factors and Multiples," Connected Mathematics Project, G. Lappan, J. Fey, W. Fitzgerald, S. Friel and E. Phillips

2000-01-01

341

eknikarationste Mass transfer andMass transfer and  

E-print Network

Convective mass transfer New 2006: Mass transfer with chemical reaction 4 erföringo New 2006: Mass transfer distillation Absorption/desorption, Packed tower columns New 2007: Extraction and leaching New 2007 strömningsteknik Biskopsgatan 8, 20500 �bo New 2007: Mixing and blending 5 eknikarationste 24302 ochSepa 4

Zevenhoven, Ron

342

Long-Distance Transfer and Routing of Static Magnetic Fields  

NASA Astrophysics Data System (ADS)

We show how the static magnetic field of a finite source can be transferred and routed to arbitrary long distances. This is achieved by using transformation optics, which results in a device made of a material with a highly anisotropic magnetic permeability. We show that a simplified version of the device, made by a superconducting-ferromagnet hybrid, also leads to an excellent transfer of the magnetic field. The latter is demonstrated with a proof-of-principle experiment where a ferromagnet tube coated with a superconductor improves the transfer of static magnetic fields with respect to conventional methods by a 400% factor over distances of 14 cm.

Navau, C.; Prat-Camps, J.; Romero-Isart, O.; Cirac, J. I.; Sanchez, A.

2014-06-01

343

Improving NASA's technology transfer process through increased screening and evaluation in the information dissemination program  

NASA Technical Reports Server (NTRS)

The current status of NASA's technology transfer system can be improved if the technology transfer process is better understood. This understanding will only be gained if a detailed knowledge about factors generally influencing technology transfer is developed, and particularly those factors affecting technology transfer from government R and D agencies to industry. Secondary utilization of aerospace technology is made more difficult because it depends on a transfer process which crosses established organizational lines of authority and which is outside well understood patterns of technical applications. In the absence of a sound theory about technology transfer and because of the limited capability of government agencies to explore industry's needs, a team approach to screening and evaluation of NASA generated technologies is proposed which calls for NASA, and other organizations of the private and public sectors which influence the transfer of NASA generated technology, to participate in a screening and evaluation process to determine the commercial feasibility of a wide range of technical applications.

Laepple, H.

1979-01-01

344

Societal and economic valuation of technology-transfer deals  

NASA Astrophysics Data System (ADS)

The industrial adoption of concepts such as open innovation brings new legitimacy to activities technology-transfer professionals have conducted for over 20 years. This movement highlights the need for an increased understanding of the valuation of intellectual property (IP) and technology-transfer deals. Valuation, though a centerpiece of corporate finance, is more challenging when applied to the inherent uncertainty surrounding innovation. Technology-transfer professionals are often overwhelmed by the complexity and data requirements of valuation techniques and skeptical of their applicability to and utility for technology transfer. The market longs for an approach which bridges the gap between valuation fundamentals and technology-transfer realities. This paper presents the foundations of a simple, flexible, precise/accurate, and useful framework for considering the valuation of technology-transfer deals. The approach is predicated on a 12-factor model—a 3×4 value matrix predicated on categories of economic, societal, and strategic value. Each of these three categories consists of three core subcategories followed by a fourth "other" category to facilitate inevitable special considerations. This 12-factor value matrix provides a framework for harvesting data during deals and for the application of best-of-breed valuation techniques which can be employed on a per-factor basis. Future work will include framework implementation within a database platform.

Holmes, Joseph S., Jr.

2009-09-01

345

Energy Transfer in Rotating Turbulence  

NASA Technical Reports Server (NTRS)

The influence or rotation on the spectral energy transfer of homogeneous turbulence is investigated in this paper. Given the fact that linear dynamics, e.g. the inertial waves regime tackled in an RDT (Rapid Distortion Theory) fashion, cannot Affect st homogeneous isotropic turbulent flow, the study of nonlinear dynamics is of prime importance in the case of rotating flows. Previous theoretical (including both weakly nonlinear and EDQNM theories), experimental and DNS (Direct Numerical Simulation) results are gathered here and compared in order to give a self-consistent picture of the nonlinear effects of rotation on tile turbulence. The inhibition of the energy cascade, which is linked to a reduction of the dissipation rate, is shown to be related to a damping due to rotation of the energy transfer. A model for this effect is quantified by a model equation for the derivative-skewness factor, which only involves a micro-Rossby number Ro(sup omega) = omega'/(2(OMEGA))-ratio of rms vorticity and background vorticity as the relevant rotation parameter, in accordance with DNS and EDQNM results fit addition, anisotropy is shown also to develop through nonlinear interactions modified by rotation, in an intermediate range of Rossby numbers (Ro(omega) = (omega)' and Ro(omega)w greater than 1), which is characterized by a marco-Rossby number Ro(sup L) less than 1 and Ro(omega) greater than 1 which is characterized by a macro-Rossby number based on an integral lengthscale L and the micro-Rossby number previously defined. This anisotropy is mainly an angular drain of spectral energy which tends to concentrate energy in tile wave-plane normal to the rotation axis, which is exactly both the slow and the two-dimensional manifold. In Addition, a polarization of the energy distribution in this slow 2D manifold enhances horizontal (normal to the rotation axis) velocity components, and underlies the anisotropic structure of the integral lengthscales. Finally is demonstrated the ability of a generalized EDQNM (Eddy Damped Quasi-Normal Markovian) model to predict the underlying spectral transfer structure and all the subsequent developments of classic anisotropy indicators in physical space, when compared to recent LES results. Even if the applications mainly concern developed strong turbulence, a particular emphasis is given to the strong formal analogy of this EDQNM2 model with recent weakly nonlinear approaches to wave-turbulence.

Cambon, Claude; Mansour, Nagi N.; Godeferd, Fabien S.; Rai, Man Mohan (Technical Monitor)

1995-01-01

346

Nuclear transfer in ruminants.  

PubMed

Ruminants were the first mammalian species to be cloned successfully by nuclear transplantation. Those experiments were designed to multiply high merit animals (Willadsen, Nature 320(6057):63-65, 1986; Prather et al., Biol Reprod 37(4):859-866, 1987; Wilmut et al., Nature 385(6619):810-813, 1997). Since then, cloning has provided us with a vast amount of knowledge and information on the reprogramming ability of somatic cells to different cell types which became an important basis for stem cell research and human medicine. Nowadays, the goals of most nuclear transfer work vary widely but in most cases the micromanipulation procedures remain the same. However, differences between species require different technical considerations. In this chapter, we describe in detail somatic cell nuclear transfer which is the foremost method for cloning ruminants with specific reference to sheep and cattle. PMID:25287336

Lee, Joon-Hee; Maalouf, Walid E

2015-01-01

347

Heat transfer in geothermal systems  

Microsoft Academic Search

Theoretical and experimental investigations of convective heat transfer in geothermal systems are reviewed. The governing equations for such heat transfer in geothermal systems are examined, along with heat transfer in hot-water, water-steam two-phase, and geopressured geothermal systems. Lumped-parameter analyses for predicting averaged reservoir characteristics during production are considered, heat transfer in other geothermal systems (e.g., dry hot rock and magma)

P. Cheng

1978-01-01

348

Technology Transfer Network and Affiliations  

NASA Technical Reports Server (NTRS)

The NASA Technology Transfer Partnership program sponsors a number of organizations around the country that are designed to assist U.S. businesses in accessing, utilizing, and commercializing NASA-funded research and technology. These organizations work closely with the Technology Transfer Offices, located at each of the 10 NASA field centers, providing a full range of technology transfer and commercialization services and assistance.

2003-01-01

349

Bakersfield College Transfer Study Data.  

ERIC Educational Resources Information Center

Data relating to the characteristics and performance of Bakersfield College (BC) students who transferred to public four-year colleges and universities in California were gathered from the transfer institutions and analyzed. Study findings included the following: (1) first-time transfers from BC to the California State University and College…

Scott, Dave

350

Exact and Approximate Radiative Transfer in Differentially Moving Media  

NASA Astrophysics Data System (ADS)

Models of the central engines in bright galactic X-ray sources and in active galactic nuclei require accurate solutions of the radiative transfer problem. Full solutions, that accommodate both diffusive and streaming photon transport through differentially moving gas, are usually too time-consuming to be used in radiation hydrodynamic simulations, and modelers therefore resort to approximate transfer schemes such as flux-limited diffusion. Exact solutions are needed to establish the accuracy and reliability of these schemes. In this paper we present exact solutions to the spherically symmetric, time-independent radiative transfer problem in differentially moving media. We compare these with solutions of truncated transfer equations, in which only terms of low order in the flow speed ? = ?c have been retained. We find that for mildly relativistic inflows, solutions of the O(?2) radiative transfer equation closely approximate the exact solutions, but that the O(?) transfer equation fails to provide a good approximation, since it cannot adequately describe radiation trapping. Exact solutions are also compared with approximate solutions obtained through flux-limited diffusion and variable Eddington factor approaches to the transfer problem. We find that both methods provide good approximations to the exact solutions but only if they are derived from transfer equations in which terms of order ?2 or higher have been retained. The O(?2) stationary-frame flux-limited diffusion method we present here is thus valid over a much wider range of conditions than existing O(?) stationary-frame methods.

Yin, Wei-Wei; Miller, Guy S.

1995-08-01

351

Median to radial nerve transfers for restoration of wrist, finger, and thumb extension.  

PubMed

Radial nerve injury results in loss of wrist, finger, and thumb extension. Traditionally, radial nerve palsies that fail to recover spontaneously have been reconstructed with tendon transfers or nerve grafts. Nerve transfers are a novel approach to the surgical management of Sunderland grade IV and V radial nerve injuries. We describe our technique for median to radial nerve transfers. In this procedure, the flexor digitorum superficialis nerve is transferred to the extensor carpi radialis brevis nerve for wrist extension, and the flexor carpi radialis nerve is transferred to the posterior interosseous nerve for finger and thumb extension. Our experience with these nerve transfers has demonstrated excellent outcomes up to 10 months after injury. Indeed, unlike tendon transfers, median to radial nerve transfers have the potential to restore normal radial nerve function, including independent finger motion. Tension-free nerve coaptation and postoperative motor re-education are critical factors to achieving these successful outcomes. PMID:23932813

Davidge, Kristen M; Yee, Andrew; Kahn, Lorna C; Mackinnon, Susan E

2013-09-01

352

Transfer of Training: Does It Truly Happen?: An Examination of Support, Instrumentality, Retention and Learner Readiness on the Transfer Motivation and Transfer of Training  

ERIC Educational Resources Information Center

Purpose: The purpose of this study is to highlight the importance of selected environmental, situational and individual factors in the training transfer process. Design/methodology/approach: This study proposes and tests a framework via structural equation modelling by including supervisor and peer support, instrumentality and learner readiness on…

Bhatti, Muhammad Awais; Battour, Mohamed Mohamed; Sundram, Veera Pandiyan Kaliani; Othman, Akmal Aini

2013-01-01

353

Factor Dazzle  

NSDL National Science Digital Library

This interactive online game helps students develop fluency with identifying factors while fostering strategic thinking. A student can play against the computer or against a friend on a 6 by 6 grid containing the numbers 1-36. Each player in turn chooses a number from the board, and then the opponent claims all of its remaining proper factors. A player's score is the sum of all the numbers and factors she/he has chosen. When there are no numbers remaining with unclaimed factors, the game ends and the player with the greater total is the winner. This game is part of NCTM's Calculation Nation project (cataloged separately). Users may login as a guest and play against the computer, or register (free) to challenge other players online.

2011-01-01

354

Analysis of Language Transfers from Thai to English in Three Types of Discourse: Explanatory, Descriptive and Persuasive.  

ERIC Educational Resources Information Center

A study on language transfer phenomenon from Thai to English is reported. The purposes of the study were to: (1) analyze the transfers from Thai to English caused by linguistic (syntax, lexis, meaning), organizational (sequence of development), style (genre, tone), and field (topic, function) factors; (2) compare the language transfers in…

Wongsothorn, Achara

1983-01-01

355

Thermal Spin Transfer Torques  

NASA Astrophysics Data System (ADS)

The coupling between spin and charge in electronic transport is studied in the field of spintronics. Heat currents are coupled to both charge and spin currents as well [1]. This extension of spintronics to what may be called ``spin caloritronics'' recently enjoys renewed attention [2]. The spin-transfer torque associated with electric currents can excite magnetizations in nanostructures, switching magnetic configuration in spin valves and move domain walls in magnetic wires when exceeding critical values of the order of 10^7Acm-2 [3]. Also heat currents transfer spin angular momentum [4], either intrinsically or via the thermoelectric generation of particle spin currents. We predict that temperature differences of the order of 100 K over typical metallic nanostructures cause effects equivalent to the critical charge current densities. In this talk I will give a brief review of various aspects of spin caloritronics with emphasis on thermal spin transfer torques. This work has been carried out in collaboration with Moosa Hatami, Qinfang Zhang, Paul Kelly, Hans Joakim Skadsem, Arne Brataas and Sadamichi Maekawa. [4pt] [1] M. Johnson and R.H. Silsbee, Phys. Rev. B 35, 4959 (1987).[0pt] [2] International Workshop on Spin Caloritronics, Lorentz Center of Leiden University, 9-13 February 2009, http://www.lorentzcenter.nl/lc/web/2009/323/info.php3?wsid=323[0pt] [3] D. C. Ralph and M. D. Stiles, J. Magn. Magn. Mater. 320, 1190 (2008).[0pt] [4] M. Hatami, G.E.W. Bauer, Q. Zhang, and P.J. Kelly, Phys. Rev. Lett. 99, 066603 (2007).

Bauer, Gerrit

2009-03-01

356

Manipulator mounted transfer platform  

DOEpatents

A transfer platform for the conveyance of objects by a manipulator includes a bed frame and saddle clamp secured along an edge of the bed frame and adapted so as to secure the bed frame to a horizontal crosspiece of the manipulator. The platform may thus move with the manipulator in a reciprocal linear path defined by a guide rail. A bed insert may be provided for the support of conveyed objects and a lifting bail may be provided to permit the manipulator arm to install the bed frame upon the crosspiece under remote control.

Dobbins, James C. (Idaho Falls, ID); Hoover, Mark A. (Idaho Falls, ID); May, Kay W. (Idaho Falls, ID); Ross, Maurice J. (Pocatello, ID)

1990-01-01

357

7 CFR 932.54 - Transfers.  

Code of Federal Regulations, 2013 CFR

...NUTS), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating...Transfers. Transfers within the area of olives from one handler to another for further...permitted. Whenever such a transfer of olives is made, the transferring...

2013-01-01

358

7 CFR 932.54 - Transfers.  

Code of Federal Regulations, 2012 CFR

...Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating...Transfers. Transfers within the area of olives from one handler to another for further...permitted. Whenever such a transfer of olives is made, the transferring...

2012-01-01

359

7 CFR 932.54 - Transfers.  

Code of Federal Regulations, 2011 CFR

...Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating...Transfers. Transfers within the area of olives from one handler to another for further...permitted. Whenever such a transfer of olives is made, the transferring...

2011-01-01

360

7 CFR 932.54 - Transfers.  

Code of Federal Regulations, 2010 CFR

...Nuts), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating...Transfers. Transfers within the area of olives from one handler to another for further...permitted. Whenever such a transfer of olives is made, the transferring...

2010-01-01

361

7 CFR 932.54 - Transfers.  

Code of Federal Regulations, 2014 CFR

...NUTS), DEPARTMENT OF AGRICULTURE OLIVES GROWN IN CALIFORNIA Order Regulating...Transfers. Transfers within the area of olives from one handler to another for further...permitted. Whenever such a transfer of olives is made, the transferring...

2014-01-01

362

Transfer LID Dysarthria Arabic Conclusions Transfer Learning for Multi-Person and  

E-print Network

Transfer LID Dysarthria Arabic Conclusions Transfer Learning for Multi-Person and Multi Arabic 5 Conclusions #12;Transfer LID Dysarthria Arabic Conclusions Outline 1 Transfer Learning 2. #12;Transfer LID Dysarthria Arabic Conclusions Fundamentals of Machine Learning What is Random

Hasegawa-Johnson, Mark

363

Polarization transfer NMR imaging  

DOEpatents

A nuclear magnetic resonance (NMR) image is obtained with spatial information modulated by chemical information. The modulation is obtained through polarization transfer from a first element representing the desired chemical, or functional, information, which is covalently bonded and spin-spin coupled with a second element effective to provide the imaging data. First and second rf pulses are provided at first and second frequencies for exciting the imaging and functional elements, with imaging gradients applied therebetween to spatially separate the nuclei response for imaging. The second rf pulse is applied at a time after the first pulse which is the inverse of the spin coupling constant to select the transfer element nuclei which are spin coupled to the functional element nuclei for imaging. In a particular application, compounds such as glucose, lactate, or lactose, can be labeled with .sup.13 C and metabolic processes involving the compounds can be imaged with the sensitivity of .sup.1 H and the selectivity of .sup.13 C.

Sillerud, Laurel O. (Los Alamos, NM); van Hulsteyn, David B. (Santa Fe, NM)

1990-01-01

364

Dams and Intergovernmental Transfers  

NASA Astrophysics Data System (ADS)

Gainers and Losers are always associated with large scale hydrological infrastructure construction, such as dams, canals and water treatment facilities. Since most of these projects are public services and public goods, Some of these uneven impacts cannot fully be solved by markets. This paper tried to explore whether the governments are paying any effort to balance the uneven distributional impacts caused by dam construction or not. It showed that dam construction brought an average 2% decrease in per capita tax revenue in the upstream counties, a 30% increase in the dam-location counties and an insignificant increase in downstream counties. Similar distributional impacts were observed for other outcome variables. like rural income and agricultural crop yields, though the impacts differ across different crops. The paper also found some balancing efforts from inter-governmental transfers to reduce the unevenly distributed impacts caused by dam construction. However, overall the inter-governmental fiscal transfer efforts were not large enough to fully correct those uneven distributions, reflected from a 2% decrease of per capita GDP in upstream counties and increase of per capita GDP in local and downstream counties. This paper may shed some lights on the governmental considerations in the decision making process for large hydrological infrastructures.

Bao, X.

2012-12-01

365

Important aspects of placental-specific gene transfer.  

PubMed

The placenta is a unique and highly complex organ that develops only during pregnancy and is essential for growth and survival of the developing fetus. The placenta provides the vital exchange of gases and wastes, the necessary nutrients for fetal development, acts as immune barrier that protects against maternal rejection, and produces numerous hormones and growth factors that promote fetal maturity to regulate pregnancy until parturition. Abnormal placental development is a major underlying cause of pregnancy-associated disorders that often result in preterm birth. Defects in placental stem cell propagation, growth, and differentiation are the major factors that affect embryonic and fetal well-being and dramatically increase the risk of pregnancy complications. Understanding the processes that regulate placentation is important in determining the underlying factors behind abnormal placental development. The ability to manipulate genes in a placenta-specific manner provides a unique tool to analyze development and eliminates potentially confounding results that can occur with traditional gene knockouts. Trophoblast stem cells and mouse embryos are not overly amenable to traditional gene transfer techniques. Most viral vectors, however, have a low infection rate and often lead to mosaic transgenesis. Although the traditional method of embryo transfer is intrauterine surgical implantation, the methodology reported here, combining lentiviral blastocyst infection and nonsurgical embryo transfer, leads to highly efficient and placental-specific gene transfer. Numerous advantages of our optimized procedures include increased investigator safety, a reduction in animal stress, rapid and noninvasive embryo transfer, and higher a rate of pregnancy and live birth. PMID:25110063

Kaufman, Melissa R; Albers, Renee E; Keoni, Chanel; Kulkarni-Datar, Kashmira; Natale, David R; Brown, Thomas L

2014-10-15

366

Computational chemistry and aeroassisted orbital transfer vehicles  

NASA Technical Reports Server (NTRS)

An analysis of the radiative heating phenomena encountered during a typical aeroassisted orbital transfer vehicle (AOTV) trajectory was made to determine the potential impact of computational chemistry on AOTV design technology. Both equilibrium and nonequilibrium radiation mechanisms were considered. This analysis showed that computational chemistry can be used to predict (1) radiative intensity factors and spectroscopic data; (2) the excitation rates of both atoms and molecules; (3) high-temperature reaction rate constants for metathesis and charge exchange reactions; (4) particle ionization and neutralization rates and cross sections; and (5) spectral line widths.

Cooper, D. M.; Jaffe, R. L.; Arnold, J. O.

1985-01-01

367

A research on the moderate transference of China's agricultural labor.  

PubMed

Examining the economic impact of large transfers of agricultural laborers to other occupations in China, this article argues in favor of moderate transference and provides specific measures for accomplishing that level of relocation. In 1979, China adopted a rural economic reform which prompted a total of 54.6 million farmers to transfer to other occupations over the next decade. Despite the transfers, the authors calculate that there remains an agricultural labor surplus of 70 million. While some maintain that accelerated transference of agricultural labor is necessary to achieve economic growth, the article points out not only the obstacles to accelerated transference but also its detrimental economic impact. 3 main factors hinder accelerated transference: the limited capacity of urban areas to absorb new labor, the limited amount of funds for investments needed to make the transfer possible, and the limited amount of energy and raw materials. Given China's current situation, accelerate transfers would only worsen the overcrowding of cities, aggravate the shortages of energy and raw materials, and retard economic progress by increasing inflation. The authors explain that China's particular situation calls for a policy of moderate transference, one that takes into account land output value, the capacity of nonagricultural sectors to absorb new labor, and the capacity of urban areas to absorb people. The authors propose the following 4 general measures that such a policy should include: 1) promoting technological development in rural areas, 2) adjusting and expanding the various structures in township enterprises, 3) favoring central townships, and 4) improving rural education. Within each of these general measures, the authors offer more specific recommendations. PMID:12343586

Li, H; Wu, M; Zhu, J; Wu, G

1990-01-01

368

Power Factor  

NSDL National Science Digital Library

All About Circuits is a website that â??provides a series of online textbooks covering electricity and electronics.â? Written by Tony R. Kuphaldt, the textbooks available here are wonderful resources for students, teachers, and anyone who is interested in learning more about electronics. This specific section, Power Factor, is the eleventh chapter in Volume II â??Alternating Current. A few of the topics covered in this chapter include: True, Reactive, and Apparent power; Calculating power factor, and Practical power factor correction. Diagrams and detailed descriptions of concepts are included throughout the chapter to provide users with a comprehensive lesson. Visitors to the site are also encouraged to discuss concepts and topics using the All About Circuits discussion forums (registration with the site is required to post materials).

Kuphaldt, Tony R.

369

TENSORIAL FACTORIZATION METHODS FOR MANIPULATION OF FACE VIDEOS  

Microsoft Academic Search

This paper proposes the use of Tensor Factorization for manipulating videos of human faces. Decomposition of a video represented as a tensor into non-negative rank-1 factors results in sparse and separable factors equivalent to a local parts decomposition of the object in the video. Such a decomposition can be used for tasks like expression transfer and face morphing. For instance,

S. Manikandan; Ranjeeth Kumar; C. V. Jawahar

370

Multi-neutron transfer reactions at sub-barrier energies.  

SciTech Connect

The optimum conditions for multi-neutron transfer have been studied in the system {sup 58}Ni + {sup 124}Sn at bombarding energies at and below the Coulomb barrier. The experiments were performed in inverse kinematics with a {sup 124}Sn beam bombarding a {sup 58}Ni target. The particles were identified with respect to mass and Z in the split-pole spectrograph with a hybrid focal plane detector with mass and Z-resolutions of A/{Delta}A = 150 and Z/{Delta}Z = 70. At all energies the transfer of up to 6 neutrons was observed. The yields for these transfer reactions are found to decrease by about a factor of four for each transferred neutron.

Rehm, K. E.

1998-01-20

371

Investigations of Planet Formation with Combined Hydrodynamics and Radiative Transfer  

NASA Astrophysics Data System (ADS)

Our aim is to investigate how the dynamics of protoplanetary disks are affected by environmental factors such as the presence of a planetary-mass object orbiting at the midplane and the radiation produced by the disk's host star. To accomplish this task we utilize the finite-volume numerical code PLUTO (Mignone, et al. 2007) to compute the evolution of the disk as a magnetohydrodynamics (MHD) simulation in 3D spherical coordinates, combined with a radiative transfer code (Jang-Condell 2008). At each iteration of the PLUTO simulation we will apply the radiative transfer code to the disk profile to model both processes simultaneously. The combined MHD and radiative transfer simulation will provide us with a much more accurate description of protoplanetary disk evolution than either isolated disk MHD or static disk radiative transfer models could individually.

Jang-Condell, Hannah; Kloster, D.

2014-01-01

372

Air-ground information transfer in the National Airspace System  

NASA Technical Reports Server (NTRS)

This paper reviews NASA's Aviation Safety Reporting System incident data for a two-year period in order to identify the frequency of air-ground information transfer errors and the factors associated with their occurrence. Of the more than 14,000 primary reports received during the 1985 and 1986 reporting period, one out of four reports concerned problems of information transfer between aircraft and ATC. Approximately half of these errors were associated directly or indirectly with aircraft deviations from assigned heading or altitude. The majority of incidents cited some human-system problem such as workload, cockpit distractions, etc., as the primary contributing factor. Improvements in air-ground information transfer using existing and future (e.g., data link) technology are proposed centering on the development and application of user-centered information management principles.

Lee, Alfred T.; Lozito, Sandra

1989-01-01

373

Cash transfers for HIV prevention: considering their potential  

PubMed Central

Introduction Cash payments to vulnerable households and/or individuals have increasingly garnered attention as a means to reduce poverty, improve health and achieve other development-related outcomes. Recent evidence from Malawi and Tanzania suggests that cash transfers can impact HIV-related behaviours and outcomes and, therefore, could serve as an important addition to HIV prevention efforts. Discussion This article reviews the current evidence on cash transfers for HIV prevention and suggests unresolved questions for further research. Gaps include (1) understanding more about the mechanisms and pathways through which cash transfers affect HIV-related outcomes; (2) addressing key operational questions, including the potential feasibility and the costs and benefits of different models of transfers and conditionality; and (3) evaluating and enhancing the wider impacts of cash transfers on health and development. Conclusions Ongoing and future studies should build on current findings to unpack unresolved questions and to collect additional evidence on the multiple impacts of transfers in different settings. Furthermore, in order to address questions on sustainability, cash transfer programmes need to be integrated with other sectors and programmes that address structural factors such as education and programming to promote gender equality and address HIV. PMID:23972159

Heise, Lori; Lutz, Brian; Ranganathan, Meghna; Watts, Charlotte

2013-01-01

374

Theoretical Study of Excitation Energy Transfer in DNA Photolyase  

PubMed Central

Photolyase (PL) is a DNA repair enzyme which splits UV light-induced thymine dimers on DNA by an electron transfer reaction occurring between the photoactivated FADH? cofactor and the DNA dimer in the DNA/PL complex. The crystal structure of the DNA/photolyase complex from Anacystis nidulans has been solved. Here, using the experimental crystal structure, we re-examine the details of the repair electron transfer reaction and address the question of energy transfer from the antenna HDF to the redox active FADH? cofactor. The photoactivation of FADH? immediately preceding the electron transfer is a key step in the repair mechanism that is largely left unexamined theoretically. An important butterfly thermal motion of flavin is identified in ab initio calculations; we propose its role in the back electron transfer from DNA to photolyase. Molecular dynamics simulation of the whole protein/DNA complex is carried out to obtain relevant cofactor conformations for ZINDO/S spectroscopic absorption and fluorescence calculations. We find that significant thermal broadening of the spectral lines, due to protein dynamics, as well as the alignment of the donor HDF and the acceptor FADH? transition dipole moments both contribute to the efficiency of energy transfer. The geometric factor of Förster’s dipolar coupling is calculated to be 1.82, a large increase from the experimentally estimated 0.67. Using Förster's mechanism, we find that the energy transfer occurs with remarkable efficiency, comparable with the experimentally determined value of 98%. PMID:18588340

Zheng, Xuehe; Garcia, Jorge; Stuchebrukhov, Alexei A.

2009-01-01

375

Theoretical study of excitation energy transfer in DNA photolyase.  

PubMed

Photolyase (PL) is a DNA repair enzyme which splits UV light-induced thymine dimers on DNA by an electron transfer reaction occurring between the photoactivated FADH(-) cofactor and the DNA dimer in the DNA/PL complex. The crystal structure of the DNA/photolyase complex from Anacystis nidulans has been solved. Here, using the experimental crystal structure, we re-examine the details of the repair electron transfer reaction and address the question of energy transfer from the antenna HDF to the redox active FADH(-) cofactor. The photoactivation of FADH(-) immediately preceding the electron transfer is a key step in the repair mechanism that is largely left unexamined theoretically. An important butterfly thermal motion of flavin is identified in ab initio calculations; we propose its role in the back electron transfer from DNA to photolyase. Molecular dynamics simulation of the whole protein/DNA complex is carried out to obtain relevant cofactor conformations for ZINDO/S spectroscopic absorption and fluorescence calculations. We find that significant thermal broadening of the spectral lines, due to protein dynamics, as well as the alignment of the donor HDF and the acceptor FADH(-) transition dipole moments both contribute to the efficiency of energy transfer. The geometric factor of Förster's dipolar coupling is calculated to be 1.82, a large increase from the experimentally estimated 0.67. Using Förster's mechanism, we find that the energy transfer occurs with remarkable efficiency, comparable with the experimentally determined value of 98%. PMID:18588340

Zheng, Xuehe; Garcia, Jorge; Stuchebrukhov, Alexei A

2008-07-24

376

Technology transfer within the government  

NASA Technical Reports Server (NTRS)

The report of a workshop panel concerned with technology transfer within the government is presented. The presentation is made in vugraph form. The assigned subtopic for this panel are as follows: (1) transfer from non-NASA US government technology developers to NASA space missions/programs; and (2) transfer from NASA to other US government space mission programs. A specific area of inquiry was Technology Maturation Milestones. Three areas were investigated: technology development; advanced development; and flight hardware development.

Russell, John

1992-01-01

377

High temperature heat transfer equipment  

Microsoft Academic Search

Various alternative methods of high temperature heat transfer in the range of 300 to 750 F, such as direct firing, forced\\u000a circulation of heat transfer fluids such as water, oil, Therminol, Dowtherm and other fluids are outlined. Advantages and\\u000a disadvantages of each are discussed. Important considerations include design of heaters, temperature uniformity, heat transfer\\u000a rates, safety precautions, hardware required, control

E. E. magnuson

1971-01-01

378

Aerobraking orbital transfer vehicle  

NASA Technical Reports Server (NTRS)

An aerobraking orbital transfer vehicle which includes an aerobraking device which also serves as a heat shield in the shape of a raked-off elliptic or circular cone with a circular or elliptical base, and with an ellipsoid or other blunt shape nose. The aerobraking device is fitted with a toroid-like skirt and is integral with the support structure of the propulsion system and other systems of the space vehicle. The vehicle is intended to be transported in components to a space station in lower earth orbit where it is assembled for use as a transportation system from low earth orbit to geosynchronous earth orbit and return. Conventional guidance means are included for autonomous flight.

Scott, Carl D. (Inventor); Nagy, Kornel (Inventor); Roberts, Barney B. (Inventor); Ried, Robert C. (Inventor); Kroll, Kenneth R. (Inventor); Gamble, Joe (Inventor)

1989-01-01

379

Post Baccalaureate Reverse Transfer Implications for Community College Student Services.  

ERIC Educational Resources Information Center

This paper asserts that a sizeable number of students at the community college have attained a baccalaureate degree or higher and have returned to the community college to take credit courses. These post-baccalaureate reverse transfer students (PRTS) enroll in the community college for a variety of reasons, but one of the more common factors is…

Pope, Myron; Turner, Mary; Barker, John

380

Entrance heat transfer in isosceles and right triangular ducts  

Microsoft Academic Search

Heat transfer in noncircular ducts is an important factor in the design of compact heat exchangers. A Galerkin-based integral method is presently used to conduct the requisite computations. The fully developed velocity distribution is obtained independent of the energy equation, because the physical properties do not depend on temperature. More accurate results may be obtained for right-triangular ducts with small

R. Lakshminarayanan; A. Haji-Sheikh

1992-01-01

381

Action Learning: How Learning Transfers from Entrepreneurs to Small Firms  

ERIC Educational Resources Information Center

This paper presents research with small- and medium-sized enterprise (SME) owners who have participated in a leadership development programme. The primary focus of this paper is on learning transfer and factors affecting it, arguing that entrepreneurs must engage in "action" in order to "learn" and that under certain conditions…

Jones, Karen; Sambrook, Sally A.; Pittaway, Luke; Henley, Andrew; Norbury, Heather

2014-01-01

382

College Distance from Home: Implications for Student Transfer Behavior  

ERIC Educational Resources Information Center

This study explored college distance from home, a possible contributing factor of transfer behavior. Because the distance between a student's home and college has been found to be related negatively to social integration and positively to homesickness (i.e., Brooks & DuBois, 1995; Fisher, Murray, & Frazer, 1985; Tognoli, 2003), a…

Mattern, Krista D.; Wyatt, Jeffrey N.; Shaw, Emily J.

2013-01-01

383

Prediction of irregular axisymmetric combustor aerodynamics and convective heat transfer  

Microsoft Academic Search

A numerical procedure for the prediction of flow and heat transfer in irregular axisymmetric combustion chambers has been developed, in which a set of porosity factors, ranging between 0.0 and 1.0, is assigned to each grid node to simulate blocked regions in the solution domain or at its boundaries. In this procedure, the governing transport equations for mass, momentum, and

M. M. M. Abou-Ellail

1985-01-01

384

Development and Testing of Emergency Department Patient Transfer Communication Measures  

ERIC Educational Resources Information Center

Purpose: Communication problems are a major contributing factor to adverse events in hospitals. The contextual environment in small rural hospitals increases the importance of emergency department (ED) patient transfer communication quality. This study addresses the communication problems through the development and testing of ED quality…

Klingner, Jill; Moscovice, Ira

2012-01-01

385

Preweaning growth characteristics for Brahman-Angus embryo transfer calves  

E-print Network

Effects of factors affecting birth weight and weaning weight of 3-4 Brahman x ;,4 Angus and 3-4 Angus x 14 Brahman embryo transfer calves were analyzed. Data used in this project were collected at the Angleton Research Station. Backcross matings...

Cook, Billy Jack

2012-06-07

386

Information transfer during contingency operations: Emergency air-ground communications  

NASA Technical Reports Server (NTRS)

Safety related problems are reported which occur as a consequence of information transfer deficiencies that arise when air/ground communications are (or should be) used as a resource in inflight emergency situations. The system factors, the human errors, and the associated causes of these problem are defined.

Porter, R. F.

1981-01-01

387

A Validation Study of a Transferred Group Intelligence Test  

Microsoft Academic Search

The purpose of the research was to conduct a validation study of a transferred group intelligence test. The Lorge-Thorndike Intelligence Test, Level A, Form 1 was translated to Hebrew and administered to an Israeli sample comparable to the original norming group. The results obtained were concerned with variability, reliability, validity, item analysis, intercorrelations among subtests, and factor analysis. While few

Mordechai Miron

1977-01-01

388

Teacher's Toolkit: Teaching for transferal  

NSDL National Science Digital Library

An area of cognitive science that may one day help connect neuroscience and education is the concept of transferal. Transferal refers to how the skills and knowledge learned in a classroom can be synthesized and taken into the real world. Of specific interest to science teachers is having students transfer their understanding of how to conduct an experiment to the real-world practices of working scientists. An additional goal of classroom instruction is to promote science as inquiry. To hone your middle school students inquiry and transferal skills, try implementing the following series of experiments into your science curriculum.

Kristen Curry

2006-04-01

389

Bilayer Approaches for Nanoparticle Phase Transfer  

NASA Astrophysics Data System (ADS)

Nanoparticles (NPs) are often synthesized in organic solvents due to advantages of superior size and shape control obtainable in a non-polar environment. However, many applications featuring NPs require them to be in aqueous media. To transfer NPs from oil to water, surfactants with amphiphilic (hydrophobic and hydrophilic) groups have been widely used. A popular phase-transfer approach involves formation of oil-in-water emulsions upon which the oil storing the NPs is boiled off. In the process, surfactants form bilayers with hydrophobic groups on the NPs rendering them water-dispersible. This transfer route however is limited in that NPs aggregate to form clusters which results in poor colloidal stability and for the specific case of quantum dots (QDs), adversely impacts optical properties. It has ever since remained a challenge to devise approaches that transfer NPs from oil to water as single particles without compromising NP stability and properties. We have discovered that by simple addition of salt to water during the step of emulsion formation, NP transfer efficiency can be greatly enhanced in "salty-micelles" of surfactants. The strength of this approach lies in its simplicity and generic nature in that the transfer scheme is valid for different NP, surfactant and salt types. Using a model system with cadmium selenide (CdSe) QDs as NPs, Aerosol-OT (AOT) as the surfactant and NaCl as the salt in water, we found >90% of CdSe QDs transferred in salty-micelles of AOT which was significantly higher than the 45-55% QDs that transferred in deionized-water (DI-water) micelles of AOT. In the salty-micelle environment, QDs were found to exist predominantly as single NPs with narrow size distribution, as established by light scattering, analytical ultracentrifugation and electron microscopy. The effects of salt were in lowering aqueous solubility of AOT through "salting-out" action and in screening repulsions between like-charged head groups of AOT molecules. Electrophoresis, thermogravimetric analysis and photoluminescence measurements using a solvatochromic dye established higher surfactant coverage with greater lateral compaction for QDs in salty-micelles over the DI-micelle counterpart. Single NP characteristics along with a hydrophobic environment in laterally compact salty-micelles resulted in better retention of optical properties of QDs. Observations of a secondary effect by salt in inducing spontaneous emulsification of a hydrocarbon (octane)/AOT/brine system were systematically investigated by tracking time-variant octane droplet size and charge. Salinity levels that determine the spontaneous curvature and phase behavior of AOT were seen to influence the initial nucleation of octane droplets and their subsequent growth. The smallest octane drops (sub 50 nm) were nucleated at the optimum cross-over salinity and emergence of the liquid crystalline phase of AOT resulted in slowest growth rates. These factors contributed towards higher transfer efficiency of NPs in salty-micelles. Two applications from formulating aqueous NP suspensions by the new phase-transfer approach are described. In the first, QD and carbon-dot (C-Dot) "nanoreporters" were formulated for oil-field reservoir characterization using Neodol 91-7 (nonionic) and Avanel S150 CGN (hybrid nonionic and anionic) as surfactants. These NPs were stable to aggregation under reservoir-representative conditions (salinities: 1M NaCl, 1M KCl and 0.55M synthetic seawater; temperatures: 70-100 °C) and demonstrated flow and transport through crushed-calcite and quartz-sand columns with high breakthrough and recovery (> 90%). In the second application, tandem assembly of a cationic polymer, multivalent salt, and NPs was investigated in a microfluidic channel where charge ratio of the polymer/salt and shear from flow and device geometry determined their assembly into higher ordered structures such as gels and capsules.

Kini, Gautam Chandrakanth

390

Chirped frequency transfer: a tool for synchronization and time transfer.  

PubMed

We propose and demonstrate the phase-stabilized transfer of a chirped frequency as a tool for synchronization and time transfer. Technically, this is done by evaluating remote measurements of the transferred, chirped frequency. The gates of the frequency counters, here driven by a 10-MHz oscillation derived from a hydrogen maser, play a role analogous to the 1-pulse per second (PPS) signals usually employed for time transfer. In general, for time transfer, the gates consequently must be related to the external clock. Synchronizing observations based on frequency measurements, on the other hand, only requires a stable oscillator driving the frequency counters. In a proof of principle, we demonstrate the suppression of symmetrical delays, such as the geometrical path delay. We transfer an optical frequency chirped by around 240 kHz/s over a fiber link of around 149 km. We observe an accuracy and simultaneity, as well as a precision (Allan deviation, 18,000 s averaging interval) of the transferred frequency of around 2 × 10(-19). We apply chirped frequency transfer to remote measurements of the synchronization between two counters' gate intervals. Here, we find a precision of around 200 ps at an estimated overall uncertainty of around 500 ps. The measurement results agree with those obtained from reference measurements, being well within the uncertainty. In the present setup, timing offsets up to 4 min can be measured unambiguously. We indicate how this range can be extended further. PMID:24859656

Raupach, Sebastian M F; Grosche, Gesine

2014-06-01

391

Learning, Intention to Transfer and Transfer in Executive Education  

ERIC Educational Resources Information Center

The main aim of this study was to understand the relationship between self-reported "intention" to transfer and self-reported "actual" transfer within a population of middle and senior executives on an executive education programme. A secondary objective was to consider the relationship between these qualitative self-reports of…

Culpin, Victoria; Eichenberg, Timm; Hayward, Ian; Abraham, Priya

2014-01-01

392

Investigation of secondary DNA transfer of skin cells under controlled test conditions  

Microsoft Academic Search

There is a paucity of data on the relative transfer rates of deposited biological substances which could assist evaluation of the probability of given crime scene scenarios, especially for those relating to objects originally touched by hand. This investigation examines factors that may influence the secondary transfer of DNA from this source, including the freshness of the deposit, the nature

Mariya Goray; R. John Mitchell; Roland A. H. van Oorschot

2010-01-01

393

The Road to Equality: Report on Transfer for the Ford Foundation.  

ERIC Educational Resources Information Center

This report presents the findings of a national study initiated by the Ford Foundation to examine the policies affecting community college transfer, including obstacles to transfer and successful models for overcoming those obstacles. The first part of the document outlines current changes in higher education and identifies factors that encourage…

Hungar, Julie Yearsley; Lieberman, Janet

394

Hydration Structure of Antithrombin Conformers and Water Transfer during Reactive Loop Insertion  

Microsoft Academic Search

The serine protease inhibitor antithrombin undergoes extensive conformational changes during functional interaction with its target proteases. Changes include insertion of the reactive loop region into a ?-sheet structure in the protein core. We explore the possibility that these changes are linked to water transfer. Volumes of water transferred during inhibition of coagulation factor Xa are compared to water-permeable volumes in

Jie Liang; Maria P. McGee

1998-01-01

395

Microbial Evolution Is in the Cards: Horizontal Gene Transfer in the Classroom  

ERIC Educational Resources Information Center

Horizontal gene transfer, the exchange of genetic material between bacteria, is a potentially important factor in the degradation of synthetic compounds introduced to the environment and in the acquisition of other characteristics including antibiotic resistance. This game-based activity illustrates the role of horizontal gene transfer in the…

Kagle, Jeanne; Hay, Anthony G.

2007-01-01

396

The Effect of Scaffolded Causal Identification in the Transfer of Experimental Design Skills  

ERIC Educational Resources Information Center

A central goal of instruction is to enable learners to transfer acquired knowledge to appropriate future situations. One factor that likely promotes far transfer is conceptual coherence (cf. Murphy & Medin, 1985). For elementary and middle-school school children in middle-high-SES schools, "explicit" instruction on the Control of Variables…

Siler, Stephanie A.; Klahr, David; Willows, Kevin; Magaro, Cressida

2011-01-01

397

Transfer of metals from soil to vegetables in an area near a smelter in Nanning, China  

Microsoft Academic Search

A field survey was conducted to investigate the metal contamination in soils and vegetables, and to evaluate the possible health risks to local population through foodchain transfer near a smelter in Nanning, southern China. Contamination levels in soils and vegetables with cadmium (Cd), lead (Pb), zinc (Zn) and copper (Cu) were measured, and transfer factors (TF) from soils to vegetable

Yu-Jing Cui; Yong-Guan Zhu; Ri-Hong Zhai; Deng-Yun Chen; Yi-Zhong Huang; Yi Qiu; Jian-Zhong Liang

2004-01-01

398

How Text Difficulty and Reader Skill Affect Reliance on Word and Content Overlap in Reading Transfer  

Microsoft Academic Search

Rereading has been advocated as a useful technique for rehabilitating poor readers (e.g. Samuels, 1979). The purpose of this thesis was to examine what was remembered after reading a text to discover how this memory can be used to increase the fluency of reading related texts. Six experiments examined the factors that influence transfer for related texts. Transfer was indicated

Heather Jean Faulkner

1995-01-01

399

How text difficulty and reader skill affect reliance on word and content overlap in reading transfer  

Microsoft Academic Search

Rereading has been advocated as a useful technique for rehabilitating poor readers (e.g. Samuels, 1979). The purpose of this thesis was to examine what was remembered after reading a text to discover how this memory can be used to increase the fluency of reading related texts. Six experiments examined the factors that influence transfer for related texts. Transfer was indicated

Heather Jean Faulkner

1995-01-01

400

Leadership development training transfer: a case study of post-training determinants  

Microsoft Academic Search

Purpose – The purpose of this paper is to understand what contributes to transfer of soft-skill, leadership training. Design\\/methodology\\/approach – The paper presents a literature review resulted in five broad factors that may influence transfer of leadership training. These were used to guide a qualitative, exploratory study. Interviews were conducted with 18 participants of an extensive, soft skill oriented leadership

Yabome Gilpin-Jackson; Gervase R. Bushe

2007-01-01

401

Properties of ceramic foam catalyst supports: one-dimensional and two-dimensional heat transfer correlations  

Microsoft Academic Search

Ceramic foam catalyst supports in structured reactors promise higher external surface areas, lower pressure drop and increased heat transfer than beds of packed particles, especially for reactions limited to the external surface. Heat transfer is an important factor in highly endothermic and exothermic reactions, with the latter more compelling since hot spots, once started, propagate through the bed and lead

Y. Peng; J. T. Richardson

2004-01-01

402

Crosslinguistic Transfer in the Acquisition of Compound Words in Persian-English Bilinguals  

ERIC Educational Resources Information Center

Crosslinguistic transfer in bilingual language acquisition has been widely reported in various linguistic domains (e.g., Dopke, 1998; Nicoladis, 1999; Paradis, 2001). In this study we examined structural overlap (Dopke, 2000; Muller and Hulk, 2001) and dominance (Yip and Matthews, 2000) as explanatory factors for crosslinguistic transfer in…

Foroodi-Nejad, Farzaneh; Paradis, Johanne

2009-01-01

403

Ford Foundation Urban Community College Transfer Opportunities Program, 1983-84. Narrative Report: Phase I.  

ERIC Educational Resources Information Center

In 1983, Cuyahoga Community College (CCC), Cleveland, Ohio, initiated a project to improve the rates of persistence, retention, and success of minority students in completing a two-year academic program and transferring to a four-year college. The project addressed four factors contributing to low rates of educational persistence and transfer: (1)…

Cuyahoga Community Coll., Cleveland, OH.

404

From the Barrio to the Bucolic: The Student Transfer Experience from Hsis to Smith College  

ERIC Educational Resources Information Center

The study reported in this article examined two Hispanic-serving institutions, Miami-Dade Community College and Santa Monica College, and the innovative transfer agreements they have with Smith College, a highly selective private women's college. Factors that influence the successful transfer of women students to Smith from these HSIs are…

Wolf-Wendel, Lisa; Twombly, Susan; Morphew, Christopher; Sopcich, Joseph

2004-01-01

405

Influence of Trainee Characteristics, Instructional Satisfaction, and Organizational Climate on Perceived Learning and Training Transfer  

ERIC Educational Resources Information Center

This study examines the effect of transfer variables on trainee characteristics, instructional satisfaction, and organizational factors of perceived learning and training transfer made by a group of trainees who attended a financial training program conducted for a Korean conglomerate. Data analyses revealed several variables in the three domains…

Lim, Doo Hun; Morris, Michael Lane

2006-01-01

406

Recent and Future Measurements of the Neutron Electric Form Factor  

SciTech Connect

I review recently conducted measurements of G{sub E}{sup n} as well as precision form factor experiments at high momentum transfer that will be performed with the 11 GeV electron beam at Jefferson Lab.

Semenov, Andrei [University of Regina, Saskatchewan, S4S 0A2 (Canada)

2010-08-05

407

Applications of aerospace technology in industry. A technology transfer profile: Food technology  

NASA Technical Reports Server (NTRS)

Food processing and preservation technologies are reviewed, expected technological advances are considered including processing and market factors. NASA contributions to food technology and nutrition are presented with examples of transfer from NASA to industry.

Murray, D. M.

1971-01-01

408

Enhanced condensation heat transfer  

NASA Astrophysics Data System (ADS)

Work has centered on optimizing the design variables associated with fluted surfaces on vertical tubes and comparing the tube performance with available enhanced tubes either for vertical or horizontal operation. Data with seven fluids including a hydrocarbon, fluorocarbons, and ammonia condensing on up to 30 different tubes were obtained. Data for tubes of different effective lengths (1/2 to 4 ft) and inclination were also obtained. The primary conclusion is that the best fluted tubes can provide an enhancement in condensation coefficient by a factor of approximately 6 over smooth vertical tube performance and a factor of approximately 2 over the best enhanced commercial tubes either operating vertically or horizontally. These data, together with field test data, have formed the basis for designing two prototype condensers, one for the 60 kWe Raft River, Idaho, pilot plant and one for the 500 kWe East Mesa, California, direct contact demonstration plant.

Michel, J. W.; Murphy, R. W.

1980-07-01

409

Natural transfer of viable microbes in space  

NASA Technical Reports Server (NTRS)

The possibility and probability of natural transfer of viable microbes from Mars to Earth and Earth to Mars traveling in meteoroids during the first 0.5 Ga and the following 4 Ga are investigated, including: --radiation protection against the galactic cosmic ray nuclei and the solar rays, dose rates as a function of the meteorite's radial column mass (radius x density), combined with dose rates generated by natural radioactivity within the meteorite; and survival curves for some bacterial species using NASA's HZETRN transport code --other factors affecting microbe survival: vacuum; central meteorite temperatures at launch, orbiting, and arrival; pressure and acceleration at launch; spontaneous DNA decay; metal ion migration --mean sizes and numbers of unshocked meteorites ejected and percentage falling on Earth, using current semiempirical results --viable flight times for the microbe species Bacillus subtilis and Deinococcus radiodurans R1 --the approximate fraction of microbes (with properties like the two species studied) viably arriving on Earth out of those ejected from Mars during the period 4 Ga BP to the present time, and during the 700 Ma from 4.5 to 3.8 Ga. Similarly, from Earth to Mars. The conclusion is that if microbes existed or exist on Mars, viable transfer to Earth is not only possible but also highly probable, due to microbes' impressive resistance to the dangers of space transfer and to the dense traffic of billions of martian meteorites which have fallen on Earth since the dawn of our planetary system. Earth-to-Mars transfer is also possible but at a much lower frequency.

Mileikowsky, C.; Cucinotta, F. A.; Wilson, J. W.; Gladman, B.; Horneck, G.; Lindegren, L.; Melosh, J.; Rickman, H.; Valtonen, M.; Zheng, J. Q.

2000-01-01

410

Introductory Tools for Radiative Transfer Models  

NASA Astrophysics Data System (ADS)

Satellite data are currently so voluminous that, despite their unprecedented quality and potential for scientific application, only a small fraction is analyzed due to two factors: researchers' computational constraints and a relatively small number of researchers actively utilizing the data. Ultimately it is hoped that the terabytes of unanalyzed data being archived can receive scientific scrutiny but this will require a popularization of the methods associated with the analysis. Since a large portion of complexity is associated with the proper implementation of the radiative transfer model, it is reasonable and appropriate to make the model as accessible as possible to general audiences. Unfortunately, the algorithmic and conceptual details that are necessary for state-of-the-art analysis also tend to frustrate the accessibility for those new to remote sensing. Several efforts have been made to have web- based radiative transfer calculations, and these are useful for limited calculations, but analysis of more than a few spectra requires the utilization of home- or server-based computing resources. We present a system that is designed to allow for easier access to radiative transfer models with implementation on a home computing platform in the hopes that this system can be utilized in and expanded upon in advanced high school and introductory college settings. This learning-by-doing process is aided through the use of several powerful tools. The first is a wikipedia-style introduction to the salient features of radiative transfer that references the seminal works in the field and refers to more complicated calculations and algorithms sparingly5. The second feature is a technical forum, commonly referred to as a tiki-wiki, that addresses technical and conceptual questions through public postings, private messages, and a ranked searching routine. Together, these tools may be able to facilitate greater interest in the field of remote sensing.

Feldman, D.; Kuai, L.; Natraj, V.; Yung, Y.

2006-12-01

411

Horizontal gene transfer in chromalveolates  

Microsoft Academic Search

BACKGROUND: Horizontal gene transfer (HGT), the non-genealogical transfer of genetic material between different organisms, is considered a potentially important mechanism of genome evolution in eukaryotes. Using phylogenomic analyses of expressed sequence tag (EST) data generated from a clonal cell line of a free living dinoflagellate alga Karenia brevis, we investigated the impact of HGT on genome evolution in unicellular chromalveolate

Tetyana Nosenko; Debashish Bhattacharya

2007-01-01

412

Gene transfer technology in aquaculture  

Microsoft Academic Search

The gene transfer technique, transgenesis, has permitted the transfer of genes from one organism to another to create new lineages of organisms with improvement in traits important to aquaculture. Genetically modified organisms (GMOs), therefore, hold promise for producing genetic improvements, such as enhanced growth rate, increased production and efficiency, disease resistance and expanded ecological ranges. The basic procedure to generate

J. A. Levy; L. F. Marins; A. Sanchez

2000-01-01

413

Children's Understanding of Ownership Transfers  

ERIC Educational Resources Information Center

An understanding of ownership entails the recognition that ownership can be transferred permanently and the ability to differentiate legitimate from illegitimate transfers. Two experiments explored the development of this understanding in 2-, 3-, 4- and 5-year olds, using stories about gift-giving and stealing. The possibility that children use…

Blake, Peter R.; Harris, Paul L.

2009-01-01

414

Early School Transfer: Teacher Voices  

ERIC Educational Resources Information Center

This empirical research involves the investigation of teachers' perceptions of a school transfer scheme whereby children aged 11+ years transfer permanently from primary to secondary school four weeks before the end of the summer term, in mid-June, in a small English town. Expressed perceptions of the secondary school staff concerning the…

Maun, Ian; Trend, Roger

2009-01-01

415

Electron transfer: Lower tunnel barriers  

NASA Astrophysics Data System (ADS)

A better understanding of electron transfer through molecules could provide the basis for many technological breakthroughs. Now, the rate of electron transfer has been enhanced in a family of molecules by making them more rigid, and this phenomenon may be explained by the loss of electronic energy to vibrations.

Miller, John R.

2014-10-01

416

Transfer Rate Report, Spring 1999.  

ERIC Educational Resources Information Center

This study attempts to discern the rate at which first-time-in-college (FTIC) Austin Community College (ACC) (Texas) students transfer to senior institutions, and which senior institutions they choose to attend. Highlights of the report include: (1) From 1990-1993, Austin Community College students transferred to four-year institutions at a higher…

Austin Community Coll., TX.

417

West Virginia University Transfer Guide  

E-print Network

standards. Transfer students with fewer than 24 transferable credit hours, must also meet freshman one and forty three credits are selected from the Nine Core areas designed to help WVU students Education Credits (GEC), visit: http://registrar.wvu.edu/current_students/gec_description #12;WVU requires

Mohaghegh, Shahab

418

Bakersfield College Transfer Study Data.  

ERIC Educational Resources Information Center

Data provided by the University of California (UC) and California State University and Colleges (CSUC) were analyzed to identify enrollment trends and assess academic performance among transfer students from Bakersfield College. Study findings included the following: (1) first-time transfers from Bakersfield College to CSUC decreased from 391 in…

Scott, David C.

419

Cooper pair transfer in nuclei  

NASA Astrophysics Data System (ADS)

The second-order distorted wave Born approximation implementation of two-particle transfer direct reactions which includes simultaneous and successive transfer, properly corrected by non-orthogonality effects, is tested with the help of controlled nuclear structure and reaction inputs against data spanning the whole mass table, and showed to constitute a quantitative probe of nuclear pairing correlations.

Potel, G.; Idini, A.; Barranco, F.; Vigezzi, E.; Broglia, R. A.

2013-10-01

420

Providing global WLCG transfer monitoring  

NASA Astrophysics Data System (ADS)

The WLCG[1] Transfers Dashboard is a monitoring system which aims to provide a global view of WLCG data transfers and to reduce redundancy in monitoring tasks performed by the LHC experiments. The system is designed to work transparently across LHC experiments and across the various technologies used for data transfer. Currently each LHC experiment monitors data transfers via experiment-specific systems but the overall cross-experiment picture is missing. Even for data transfers handled by FTS, which is used by 3 LHC experiments, monitoring tasks such as aggregation of FTS transfer statistics or estimation of transfer latencies are performed by every experiment separately. These tasks could be performed once, centrally, and then served to all experiments via a well-defined set of APIs. In the design and development of the new system, experience accumulated by the LHC experiments in the data management monitoring area is taken into account and a considerable part of the code of the ATLAS DDM Dashboard is being re-used. The paper describes the architecture of the Global Transfer monitoring system, the implementation of its components and the first prototype.

Andreeva, J.; Dieguez Arias, D.; Campana, S.; Flix, J.; Keeble, O.; Magini, N.; Molnar, Z.; Oleynik, D.; Petrosyan, A.; Ro, G.; Saiz, P.; Salichos, M.; Tuckett, D.; Uzhinsky, A.; Wildish, T.

2012-12-01

421

BYU Registrar's Office Transfer Evaluation  

E-print Network

explain this process: · To receive credit for a specific BYU course or General Education requirement, you in both the native language and in English. If you are unable to provide course descriptions, only general that is determined to be vocational is not transferable. · A-level or GCE credit will transfer only as elective

Hart, Gus

422

Feasibilitystudy: Transfer ISACs Graphical Userinterface  

E-print Network

Feasibilitystudy: Transfer ISACs Graphical Userinterface To Web2.0 Technology Wolfgang Kandlbauer to web2.0 I compared some different technologies. During my work I sorted out which of these are more . . . . . . . 11 3 Transfer to Web2.0 13 3.1 Survey on relevant Web2.0 technologies . . . . . . . . . . . . . . 13

423

Utrecht Radiative Transfer Courses  

NASA Astrophysics Data System (ADS)

The Utrecht course ``The Generation and Transport of Radiation'' teaches basic radiative transfer to second-year students. It is a much-expanded version of the first chapter of Rybicki & Lightman's ``Radiative Processes in Astrophysics''. After this course, students understand why intensity is measured per steradian, have an Eddington-Barbier feel for optically thick line formation, and know that scattering upsets LTE. The text is a computer-aided translation by Ruth Peterson of my 1992 Dutch-language course. My aim is to rewrite this course in non-computer English and make it web-available at some time. In the meantime, copies of the Peterson translation are made yearly at Uppsala -- ask them, not me. Eventually it should become a textbook. The Utrecht course ``Radiative Transfer in Stellar Atmospheres'' is a 30-hour course for third-year students. It treats NLTE line formation in plane-parallel stellar atmospheres at a level intermediate between the books by Novotny and Boehm-Vitense, and Mihalas' ``Stellar Atmospheres''. After this course, students appreciate that epsilon is small, that radiation can heat or cool, and that computers have changed the field. This course is web-available since 1995 and is regularly improved -- but remains incomplete. Eventually it should become a textbook. The three Utrecht exercise sets ``Stellar Spectra A: Basic Line Formation'', ``Stellar Spectra B: LTE Line Formation'', and ``Stellar Spectra C: NLTE Line Formation'' are IDL-based computer exercises for first-year, second-year, and third-year students, respectively. They treat spectral classification, Saha-Boltzmann population statistics, the curve of growth, the FAL-C solar atmosphere model, the role of H-minus in the solar continuum, LTE formation of Fraunhofer lines, inversion tactics, the Feautrier method, classical lambda iteration, and ALI computation. The first two sets are web-available since 1998; the third will follow. Acknowledgement. Both courses owe much to previous Utrecht courses taught by the late Kees Zwaan. The third exercise set was developed by Phil Judge, Mandy Hagenaar, and Thijs Krijger. Reverse acknowledgement. If you are a user of this free material you might refer to this summary and so boost my citation standing. Corrections are also welcome.

Rutten, R. J.

2003-01-01

424

Energy Transfer in Musical Instruments  

NSDL National Science Digital Library

This lesson covers concepts of energy and energy transfer, with a focus on energy transfer in musical instruments. More specifically, students learn the two different ways in which energy can be transferred between a system and its environment. The law of conservation of energy is also described. Example systems are presented (two cars on a track and a tennis ball falling to the ground) and students make predictions and explain the energy transfer mechanisms. The engineering focus becomes clear in the associated activity when students apply the concepts learned in the lesson to design musical instruments. The systems analyzed in the lesson help in discussing how to apply conservation of energy and energy transfer to make things.

Engineering K-PhD Program,

425

High temperature gas energy transfer  

NASA Astrophysics Data System (ADS)

A summary of a report on high temperature gas energy transfer discusses the following topics: (1) development of a new method called the Diffusion Cloud Method for the study of intermolecular vibrational energy transfer in reacting unimolecular systems; (2) development of the theory and method of a new technique called the Variable Encounter Method for the study of sequential vibrational energy transfer between gas molecules and hot surfaces; (3) a critique of the exact vibrational state computational algorithmn of Beyer-Swinehart-Stein-Rabinovitch was given; (4) a theoretical illustration of a model for V-T,R vibrational energy transfer restricted by angular momentum conservation was given; and (5) theoretical treatment of a Boltzmann strong collision model has led to generalizations on energy transfer efficiency as a function of both molecule size ambient temperature and hot molecule energy level.

Rabinovitch, B. S.

1985-12-01

426

Conduction heat transfer solutions  

SciTech Connect

This text is a collection of solutions to a variety of heat conduction problems found in numerous publications, such as textbooks, handbooks, journals, reports, etc. Its purpose is to assemble these solutions into one source that can facilitate the search for a particular problem solution. Generally, it is intended to be a handbook on the subject of heat conduction. This material is useful for engineers, scientists, technologists, and designers of all disciplines, particularly those who design thermal systems or estimate temperatures and heat transfer rates in structures. More than 500 problem solutions and relevant data are tabulated for easy retrieval. There are twelve sections of solutions which correspond with the class of problems found in each. Geometry, state, boundary conditions, and other categories are used to classify the problems. A case number is assigned to each problem for cross-referencing, and also for future reference. Each problem is concisely described by geometry and condition statements, and many times a descriptive sketch is also included. At least one source reference is given so that the user can review the methods used to derive the solutions. Problem solutions are given in the form of equations, graphs, and tables of data, all of which are also identified by problem case numbers and source references.

VanSant, J.H.

1980-03-01

427

Conduction heat transfer solutions  

SciTech Connect

This text is a collection of solutions to a variety of heat conduction problems found in numerous publications, such as textbooks, handbooks, journals, reports, etc. Its purpose is to assemble these solutions into one source that can facilitate the search for a particular problem solution. Generally, it is intended to be a handbook on the subject of heat conduction. There are twelve sections of solutions which correspond with the class of problems found in each. Geometry, state, boundary conditions, and other categories are used to classify the problems. Each problem is concisely described by geometry and condition statements, and many times a descriptive sketch is also included. The introduction presents a synopsis on the theory, differential equations, and boundary conditions for conduction heat transfer. Some discussion is given on the use and interpretation of solutions. Supplementary data such as mathematical functions, convection correlations, and thermal properties are included for aiding the user in computing numerical values from the solutions. 155 figs., 92 refs., 9 tabs.

VanSant, J.H.

1983-08-01

428

Heat transfer additives for absorption cooling system fluids  

NASA Astrophysics Data System (ADS)

The work was directed towards developing a quantitative understanding of the phenomena that can enhance the heat and mass transfer in the absorber of an absorption chiller. Emphasis during the first year of a 3 year study was placed on compiling a comprehensive property data base and doing some exploratory experiments. During the second year experimental methods associated with heat and mass transfer in a falling film absorber were emphasized. All experiments used 2-ethyl-1-hexanal as the additive (surfactant) in an aqueous LiBr solution. The mass and heat transfer coefficients were found using the log mean averages based on the inlet and outlet properties. Significant accomplishments include: the onset of enhanced transfer was in the 2 to 200 ppm additive concentration range of surfactant and when 30 ppm was reached in the experiments the maximum enhancement was achieved. From 30 to 200 ppm additive concentration the enhancement remained the same. Visual observations of the experiments using the long absorber (85 cm) showed that chaotic flow was occurring only over the first half of the absorber. The majority of the tests were done with 100 ppm solutions of the surfactant. Tests as a function of absorber length showed that the mass transfer for 60% solution was about a factor of two. Tests on 50% LiBr showed an increase of a factor of 5.7 over the first 40 cm of length.

Wood, B. D.; Berman, N. S.; Kim, K.; Chau, D. S. C.

1993-03-01

429

Proton-Coupled Electron Transfer  

SciTech Connect

Proton-Coupled Electron Transfer (PCET) describes reactions in which there is a change in both electron and proton content between reactants and products. It originates from the influence of changes in electron content on acid?base properties and provides a molecular-level basis for energy transduction between proton transfer and electron transfer. Coupled electron?proton transfer or EPT is defined as an elementary step in which electrons and protons transfer from different orbitals on the donor to different orbitals on the acceptor. There is (usually) a clear distinction between EPT and H-atom transfer (HAT) or hydride transfer, in which the transferring electrons and proton come from the same bond. Hybrid mechanisms exist in which the elementary steps are different for the reaction partners. EPT pathways such as PhO•/PhOH exchange have much in common with HAT pathways in that electronic coupling is significant, comparable to the reorganization energy with H{sub DA} ~ ?. Multiple-Site Electron?Proton Transfer (MS-EPT) is an elementary step in which an electron?proton donor transfers electrons and protons to different acceptors, or an electron?proton acceptor accepts electrons and protons from different donors. It exploits the long-range nature of electron transfer while providing for the short-range nature of proton transfer. A variety of EPT pathways exist, creating a taxonomy based on what is transferred, e.g., 1e{sup -}/2H{sup +} MS-EPT. PCET achieves “redox potential leveling” between sequential couples and the buildup of multiple redox equivalents, which is of importance in multielectron catalysis. There are many examples of PCET and pH-dependent redox behavior in metal complexes, in organic and biological molecules, in excited states, and on surfaces. Changes in pH can be used to induce electron transfer through films and over long distances in molecules. Changes in pH, induced by local electron transfer, create pH gradients and a driving force for long-range proton transfer in Photosysem II and through other biological membranes. In EPT, simultaneous transfer of electrons and protons occurs on time scales short compared to the periods of coupled vibrations and solvent modes. A theory for EPT has been developed which rationalizes rate constants and activation barriers, includes temperature- and driving force (?G)-dependences implicitly, and explains kinetic isotope effects. The distance-dependence of EPT is dominated by the short-range nature of proton transfer, with electron transfer being far less demanding.Changes in external pH do not affect an EPT elementary step. Solvent molecules or buffer components can act as proton donor acceptors, but individual H2O molecules are neither good bases (pK{sub a}(H{sub 3}O{sup +}) = ?1.74) nor good acids (pK{sub a}(H{sub 2}O) = 15.7). There are many examples of mechanisms in chemistry, in biology, on surfaces, and in the gas phase which utilize EPT. PCET and EPT play critical roles in the oxygen evolving complex (OEC) of Photosystem II and other biological reactions by decreasing driving force and avoiding high-energy intermediates.

Weinberg, Dave; Gagliardi, Christopher J.; Hull, Jonathan F; Murphy, Christine Fecenko; Kent, Caleb A.; Westlake, Brittany C.; Paul, Amit; Ess, Daniel H; McCafferty, Dewey Granville; Meyer, Thomas J

2012-01-01

430

An epoch-making application of discharge plasma phenomenon to gene-transfer.  

PubMed

We discovered an epoch-making gene transfer method utilizing discharge plasma. Although an electroporation method is commonly used in present gene transfer experiments, it cannot transfer genes into primary cells sufficiently. The atmospheric pressure discharge plasma employed in this study was originally used for surface treatment of non-biological materials. We hypothesized that it could provide a suitable effect on the surface of target cells and applied it to gene transfer into various types of cells. The plasma technology succeeded in the efficient transfer of green fluorescence protein (GFP) plasmid into post-mitotic neuronal cells obtained from cerebral cortices of rats, into which an electroporation with conventional equipment cannot transfer genes sufficiently, as the cells were attached. After the transfection of rat pheochromocytoma PC12 cells with the GFP gene by plasma treatment, the cells retained their function, that is, nerve growth factor-induced differentiation. Furthermore, gene transfer with the plasma technology was also applicable to other types of cell lines such as HeLa cells and Chinese hamster lung (CHL) cells as adherent cell lines, and Jurkat cells as a suspended cell line, and another type of primary cell, human umbilical vein endothelial cells (HUVEC). In conclusion, the plasma method is an epoch-making gene transfer technology which efficiently transfers genes into primary cells into which electroporation cannot transfer genes. Moreover, the method is able to universally transfer genes into various types of cells as the function of the cells was maintained. PMID:16170826

Ogawa, Yasuhiro; Morikawa, Noriyuki; Ohkubo-Suzuki, Akiko; Miyoshi, Sousuke; Arakawa, Hiroyuki; Kita, Yasuhiro; Nishimura, Shintaro

2005-12-30

431

Mass transfer in a 1370 C (2500 F) lithium thermal convection loop  

NASA Technical Reports Server (NTRS)

Experimental results from a test to evaluate interstitial element mass transfer effects on T-111, ASTAR 811C, and ASTAR 1211C after 5000 hours in flowing lithium at 1370 C (2500 F) are presented. No gross corrosion effects were observed. However, hafnium and nitrogen transfer to cooler regions within the loop were noted. Oxygen was in general removed from test specimens, but there was no evidence to indicate that it was a major factor in the mass transfer process. Carbon and hydrogen transfer were not detected.

Scheuermann, C. M.

1974-01-01

432

Mixing and mass transfer considerations in highly viscous fermentations  

SciTech Connect

Highly viscous microbial fermentations pose difficult scale-up challenges for the industrial biochemical engineer. Incomplete bulk mixing and poor oxygen mass transfer often limit fermentor titers and productivities. Lower heat transfer coefficients coupled with higher rates of heat generation through viscous dissipation further confound operational difficulties. Practical approaches to alleviating these factors will be discussed using examples from viscoelastic gellan, welan, and xanthan gum fermentations. In addition, a summary of the effects of power input, aeration, media manipulation, and genetic modifications will be discussed.

Applegate, M.A.; Flatt, J.H. [Process Research and Development, San Diego, CA (United States)

1995-12-01

433

Technology transfer of NASA microwave remote sensing system  

NASA Technical Reports Server (NTRS)

Viable techniques for effecting the transfer from NASA to a user agency of state-of-the-art airborne microwave remote sensing technology for oceanographic applications were studied. A detailed analysis of potential users, their needs and priorities; platform options; airborne microwave instrument candidates; ancillary instrumentation; and other, less obvious factors that must be considered were studied. Conclusions and recommendations for the development of an orderly and effective technology transfer of an airborne microwave system that could meet the specific needs of the selected user agencies are reported.

Akey, N. D.

1981-01-01

434

Heat transfer performance of internally finned tubes in turbulent flow  

NASA Astrophysics Data System (ADS)

The heat transfer performance for heating water in turbulent flow was experimentally determined for 11 tubes having integral internal spiral and longitudinal fins. Individual tube performance is presented and compared with a smooth tube datum at constant pumping power. A longitudinal and spiral fin tube from within the 11 tubes and a smooth tube were also tested heating a 50% w/w ethylene glycol-water solution, and these data are included. These data are compared with relevant data available in the literature. Correlating equations are presented for heat transfer and Fanning friction factor that describe the air, water, and ethylene glycol-water data within + or - 10%.

Carnavos, T. C.

1980-06-01

435

The Geometry of Radiative Transfer  

E-print Network

We present the geometry and symmetries of radiative transfer theory. Our geometrization exploits recent work in the literature that enables to obtain the Hamiltonian formulation of radiative transfer as the semiclassical limit of a phase space representation of electromagnetic theory. Cosphere bundle reduction yields the traditional description over the space of "positions and directions", and geometrical optics arises as a special case when energy is disregarded. It is also shown that, in idealized environments, radiative transfer is a Lie-Poisson system with the group of canonical transformations as configuration space and symmetry group.

Christian Lessig; Alex L. Castro

2012-06-14

436

Dynamical Treatment of Charge Transfer through Duplex Nucleic Acids Containing Modified Adenines  

PubMed Central

We address the issue of whether chemical alterations of nucleobases are an effective tool to modulate charge transfer through DNA molecules. Our investigation uses a multi-level computational approach based on classical molecular dynamics and quantum chemistry. We find yet another evidence that structural fluctuations are a key factor to determine the electronic structure of double-stranded DNA. We argue that the electronic structure and charge transfer ability of flexible polymers is the result of a complex intertwining of various structural, dynamical and chemical factors. Chemical intuition may be used to design molecular wires, but this is not the sole component in the complex charge transfer mechanism through DNA. PMID:24060008

Brancolini, Giorgia; Migliore, Agostino; Corni, Stefano; Fuentes-Cabrera, Miguel; Luque, F. Javier; Di Felice, Rosa

2014-01-01

437

New flow boiling heat transfer model for hydrocarbons evaporating inside horizontal tubes  

SciTech Connect

Hydrocarbons have high thermodynamic performances, belong to the group of natural refrigerants, and they are the main components in mixture Joule-Thomson low temperature refrigerators (MJTR). New evaluations of nucleate boiling contribution and nucleate boiling suppression factor in flow boiling heat transfer have been proposed for hydrocarbons. A forced convection heat transfer enhancement factor correlation incorporating liquid velocity has also been proposed. In addition, the comparisons of the new model and other classic models were made to evaluate its accuracy in heat transfer prediction.

Chen, G. F.; Gong, M. Q.; Wu, J. F.; Zou, X. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, P.O. Box 2711, 35, Beijing, 100190 (China); Wang, S. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, P.O. Box 2711, 35, Beijing, 100190 (China); University of Chinese Academy of Science, No. 19 YuQuan Road, Beijing, 100049 (China)

2014-01-29

438

Efficient Gene Transfer in Bacterial Cell Chains  

E-print Network

Horizontal gene transfer contributes to evolution and the acquisition of new traits. In bacteria, horizontal gene transfer is often mediated by conjugative genetic elements that transfer directly from cell to cell. Integrative ...

Babic, Ana

439

33 CFR 127.319 - LNG transfer.  

Code of Federal Regulations, 2010 CFR

...charge of transfer operations on the vessel; (2) Ensure that an inspection of the transfer piping and equipment for leaks, frost, defects, and other symptoms of safety and operational problems is conducted at least once every transfer; (3)...

2010-07-01

440

33 CFR 127.319 - LNG transfer.  

Code of Federal Regulations, 2013 CFR

...charge of transfer operations on the vessel; (2) Ensure that an inspection of the transfer piping and equipment for leaks, frost, defects, and other symptoms of safety and operational problems is conducted at least once every transfer; (3)...

2013-07-01

441

33 CFR 127.319 - LNG transfer.  

Code of Federal Regulations, 2011 CFR

...charge of transfer operations on the vessel; (2) Ensure that an inspection of the transfer piping and equipment for leaks, frost, defects, and other symptoms of safety and operational problems is conducted at least once every transfer; (3)...

2011-07-01

442

33 CFR 127.319 - LNG transfer.  

Code of Federal Regulations, 2014 CFR

...charge of transfer operations on the vessel; (2) Ensure that an inspection of the transfer piping and equipment for leaks, frost, defects, and other symptoms of safety and operational problems is conducted at least once every transfer; (3)...

2014-07-01

443

33 CFR 127.319 - LNG transfer.  

Code of Federal Regulations, 2012 CFR

...charge of transfer operations on the vessel; (2) Ensure that an inspection of the transfer piping and equipment for leaks, frost, defects, and other symptoms of safety and operational problems is conducted at least once every transfer; (3)...

2012-07-01

444

Technology Transfer Center | NCI TTC Fellowship Program  

Cancer.gov

The NCI Technology Transfer Center offers two tracks of technology transfer fellowships under the Cancer Research Training Award (CRTA) program. These fellowships provide scientists with training and mentored work experience in technology transfer.

445

Heat Transfer: From Hot to Not  

NSDL National Science Digital Library

Students learn the fundamental concepts of heat transfer and heat of reaction. This includes concepts such as physical chemistry, an equation for heat transfer, and a basic understanding of energy and heat transfer.

2014-09-18

446

Transfer research and impact studies program  

NASA Technical Reports Server (NTRS)

Methods developed for stimulating interest in the transfer of NASA-originated technology are described. These include: new information packaging concepts; technology transfer via people transfer; information management systems; data bank operations; and professional communication activities.

Freeman, J. E. (editor)

1975-01-01

447

Detecting Highways of Horizontal Gene Transfer  

E-print Network

In a horizontal gene transfer (HGT) event, a gene is transferred between two species that do not have an ancestor-descendant relationship. Typically, no more than a few genes are horizontally transferred between any two ...

Bansal, Mukul S.

448

Phylogeny Poorly Predicts the Utility of a Challenging Horizontally Transferred Gene in Methylobacterium Strains  

PubMed Central

Horizontal gene transfer plays a crucial role in microbial evolution. While much is known about the mechanisms that determine whether physical DNA can be transferred into a new host, the factors determining the utility of the transferred genes are less clear. We have explored this issue using dichloromethane consumption in Methylobacterium strains. Methylobacterium extorquens DM4 expresses a dichloromethane dehalogenase (DcmA) that has been acquired through horizontal gene transfer and allows the strain to grow on dichloromethane as the sole carbon and energy source. We transferred the dcmA gene into six Methylobacterium strains that include both close and distant evolutionary relatives. The transconjugants varied in their ability to grow on dichloromet