Two-step frequency conversion for connecting distant quantum memories by transmission through an optical fiber

NASA Astrophysics Data System (ADS)

Tamura, Shuhei; Ikeda, Kohei; Okamura, Kotaro; Yoshii, Kazumichi; Hong, Feng-Lei; Horikiri, Tomoyuki; Kosaka, Hideo

2018-06-01

Long-distance quantum communication requires entanglement between distant quantum memories. For this purpose, photon transmission is necessary to connect the distant memories. Here, for the first time, we develop a two-step frequency conversion process (from a visible wavelength to a telecommunication wavelength and back) involving the use of independent two-frequency conversion media where the target quantum memories are nitrogen-vacancy centers in diamonds (with an emission/absorption wavelength of 637.2 nm), and experimentally characterize the performance of this process acting on light from an attenuated CW laser. A total conversion efficiency of approximately 7% is achieved. The noise generated in the frequency conversion processes is measured, and the signal-to-noise ratio is estimated for a single photon signal emitted by a nitrogen-vacancy (NV) center. The developed frequency conversion system has future applications via transmission through a long optical fiber channel at a telecommunication wavelength for a quantum repeater network.

Conversion coatings prepared or treated with calcium hydroxide solutions

NASA Technical Reports Server (NTRS)

Maxey, Jason (Inventor); Nelson, Carl (Inventor); Eylem, Cahit (Inventor); Minevski, Zoran (Inventor); Clarke, Eric (Inventor)

2002-01-01

A conversion coating process that forms a stable and corrosion-resistant oxide layer on metal or metal oxide substrates or layers. Particularly, the conversion coating process involves contacting the metal or metal oxide substrate or layer with the aqueous calcium hydroxide solutions in order to convert the surface of the substrate to a stable metal oxide layer or coating. According to the present invention, the calcium hydroxide solution is prepared by removing carbon dioxide from water or an aqueous solution before introducing the calcium hydroxide. In this manner, formation of calcium carbonate particles is avoided and the porosity of the conversion coating produced by the calcium hydroxide solution is reduced to below about 1%.

A Novel NADPH-Dependent Aldehyde Reductase Gene from Saccharomyces cerevisiae NRRL Y-12632 Involved in the Detoxification of Aldehyde Inhibitors Derived from Lignocellulosic Biomass Conversion

USDA-ARS?s Scientific Manuscript database

Aldehyde inhibitors such as furfural, 5-hydroxymethylfurfural (HMF), anisaldehyde, benzaldehyde, cinnamaldehyde, and phenylaldehyde are commonly generated during lignocellulosic biomass conversion process for low-cost cellulosic ethanol production that interferes with subsequent microbial growth and...

Evaluating a Tacit Knowledge Sharing Initiative: A Case Study

ERIC Educational Resources Information Center

Gubbins, Claire; Corrigan, Siobhan; Garavan, Thomas N.; O'Connor, Christy; Leahy, Damien; Long, David; Murphy, Eamonn

2012-01-01

Purpose: This paper aims to present a case study illustrating the issues involved in the tacit knowledge conversion process and to determine whether such conversion delivers value to the organisation in terms of business value and return on investment (ROI). Design/methodology/approach: A single-case multiple baseline participants experimental…

School District Financial Management and Banking.

ERIC Educational Resources Information Center

Dembowski, Frederick L.; Davey, Robert D.

This chapter of "Principles of School Business Management" introduces the concept of cash management, or the process of managing an institution's moneys to ensure maximum cash availability and maximum yield on investments. Four activities are involved: (1) conversion of accounts receivable to cash receipts; (2) conversion of accounts payable to…

Automatic Intention Recognition in Conversation Processing

ERIC Educational Resources Information Center

Holtgraves, Thomas

2008-01-01

A fundamental assumption of many theories of conversation is that comprehension of a speaker's utterance involves recognition of the speaker's intention in producing that remark. However, the nature of intention recognition is not clear. One approach is to conceptualize a speaker's intention in terms of speech acts [Searle, J. (1969). "Speech…

Geometric and Algebraic Approaches in the Concept of Complex Numbers

ERIC Educational Resources Information Center

Panaoura, A.; Elia, I.; Gagatsis, A.; Giatilis, G.-P.

2006-01-01

This study explores pupils' performance and processes in tasks involving equations and inequalities of complex numbers requiring conversions from a geometric representation to an algebraic representation and conversions in the reverse direction, and also in complex numbers problem solving. Data were collected from 95 pupils of the final grade from…

Learning through Conversation: Exploring and Extending Teacher and Children's Involvement in Classroom Talk

ERIC Educational Resources Information Center

Brown, Kirsty; Kennedy, Hilary

2011-01-01

This article details a professional development process with a group of teachers and educational psychologists in the UK, at a school for children identified as having social, emotional, and behavioural difficulties. The project focused on how teachers use conversation to include children within dialogue and incorporate children's ideas within the…

Digital phased array beamforming using single-bit delta-sigma conversion with non-uniform oversampling.

PubMed

Kozak, M; Karaman, M

2001-07-01

Digital beamforming based on oversampled delta-sigma (delta sigma) analog-to-digital (A/D) conversion can reduce the overall cost, size, and power consumption of phased array front-end processing. The signal resampling involved in dynamic delta sigma beamforming, however, disrupts synchronization between the modulators and demodulator, causing significant degradation in the signal-to-noise ratio. As a solution to this, we have explored a new digital beamforming approach based on non-uniform oversampling delta sigma A/D conversion. Using this approach, the echo signals received by the transducer array are sampled at time instants determined by the beamforming timing and then digitized by single-bit delta sigma A/D conversion prior to the coherent beam summation. The timing information involves a non-uniform sampling scheme employing different clocks at each array channel. The delta sigma coded beamsums obtained by adding the delayed 1-bit coded RF echo signals are then processed through a decimation filter to produce final beamforming outputs. The performance and validity of the proposed beamforming approach are assessed by means of emulations using experimental raw RF data.

The 5-(4-Ethynylophenoxy) isophthalic chloride

NASA Technical Reports Server (NTRS)

Hergenrother, P. M.; Jensen, B. J. (Inventor)

1986-01-01

Sulfone-ester polymers containing pendent ethynyl groups and a direct and multistep process for preparing them are disclosed. The multistep process involves the conversion of a pendent bromo group to the ethynyl group while the direct route involves reating hydroxy-terminated sulfone oligomer or polymers with a stoichiometric amount of 5-(4-ethynylphenoxy) isophthaloyl chloride. The 5-(4-ethynylphenoxy) isophthaloyl chloride and the process for preparing it are also disclosed.

A Descriptive Study of Decision-Making Conversations during Pediatric Intensive Care Unit Family Conferences.

PubMed

Smith, Michael A; Clayman, Marla L; Frader, Joel; Arenson, Melanie; Haber-Barker, Natalie; Ryan, Claire; Emanuel, Linda; Michelson, Kelly

2018-06-19

Little is known about how decision-making conversations occur during pediatric intensive care unit (PICU) family conferences (FCs). Describe the decision-making process and implementation of shared decision making (SDM) during PICU FCs. Observational study. University-based tertiary care PICU, including 31 parents and 94 PICU healthcare professionals involved in FCs. We recorded, transcribed, and analyzed 14 PICU FCs involving decision-making discussions. We used a modified grounded theory and content analysis approach to explore the use of traditionally described stages of decision making (DM) (information exchange, deliberation, and determining a plan). We also identified the presence or absence of predefined SDM elements. DM involved the following modified stages: information exchange; information-oriented deliberation; plan-oriented deliberation; and determining a plan. Conversations progressed through stages in a nonlinear manner. For the main decision discussed, all conferences included a presentation of the clinical issues, treatment alternatives, and uncertainty. A minority of FCs included assessing the family's understanding (21%), assessing the family's need for input from others (28%), exploring the family's desired decision-making role (35%), and eliciting the family's opinion (42%). In the FCs studied, we found that DM is a nonlinear process. We also found that several SDM elements that could provide information about parents' perspectives and needs did not always occur, identifying areas for process improvement.

Metrication. A Guide for Consumers. Consumer Research Report No. 2. Third Edition.

ERIC Educational Resources Information Center

Consumer and Corporate Affairs Dept., Ottawa (Ontario).

Designed to introduce the metric system to consumers, this guide, developed in Canada, offers a brief definition and history of the metric system and rationale for change. The conversion experiences of other countries are described, and questions about learning the new system and problems involved with the conversion process are also considered.…

Catalytic processes for space station waste conversion

NASA Technical Reports Server (NTRS)

Schoonover, M. W.; Madsen, R. A.

1986-01-01

Catalytic techniques for processing waste products onboard space vehicles were evaluated. The goal of the study was the conversion of waste to carbon, wash water, oxygen and nitrogen. However, the ultimate goal is conversion to plant nutrients and other materials useful in closure of an ecological life support system for extended planetary missions. The resulting process studied involves hydrolysis at 250 C and 600 psia to break down and compact cellulose material, distillation at 100 C to remove water, coking at 450 C and atmospheric pressure, and catalytic oxidation at 450 to 600 C and atmospheric pressure. Tests were conducted with a model waste to characterize the hydrolysis and coking processes. An oxidizer reactor was sized based on automotive catalytic conversion experience. Products obtained from the hydrolysis and coking steps included a solid residue, gases, water condensate streams, and a volatile coker oil. Based on the data obtained, sufficient component sizing was performed to make a preliminary comparison of the catalytic technique with oxidation for processing waste for a six-man spacecraft. Wet oxidation seems to be the preferred technique from the standpoint of both component simplicity and power consumption.

Culture models of human mammary epithelial cell transformation

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

Stampfer, Martha R.; Yaswen, Paul

2000-11-10

Human pre-malignant breast diseases, particularly ductal carcinoma in situ (DCIS)3 already display several of the aberrant phenotypes found in primary breast cancers, including chromosomal abnormalities, telomerase activity, inactivation of the p53 gene and overexpression of some oncogenes. Efforts to model early breast carcinogenesis in human cell cultures have largely involved studies in vitro transformation of normal finite lifespan human mammary epithelial cells (HMEC) to immortality and malignancy. We present a model of HMEC immortal transformation consistent with the know in vivo data. This model includes a recently described, presumably epigenetic process, termed conversion, which occurs in cells that have overcomemore » stringent replicative senescence and are thus able to maintain proliferation with critically short telomeres. The conversion process involves reactivation of telomerase activity, and acquisition of good uniform growth in the absence and presence of TFGB. We propose th at overcoming the proliferative constraints set by senescence, and undergoing conversion, represent key rate-limiting steps in human breast carcinogenesis, and occur during early stage breast cancer progression.« less

Conversion of carbohydrate into hydrogen fuel by a photocatalytic process

NASA Astrophysics Data System (ADS)

Kawai, T.; Sakata, T.

1980-07-01

A photocatalytic process for the conversion of carbohydrates into hydrogen fuel is presented. The method involves the irradiation of sugar, starch or cellulose in the presence of water and a RuO2/TiO2/Pt catalyst, which has been found to lead to the generation of CO2 and H2 at efficiencies 100 times larger than those obtained with TiO2 alone, with no detectable amounts of other products. The reaction mechanism can be explained in terms of an electrochemical microcell, in which electron-hole pairs generated in TiO2 cause redox reactions at the surface. The process may thus be used in the conversion of solar energy stored in the form of carbohydrates by green plant photosynthesis into useful hydrogen fuels.

Reading Comprehension in Boys with ADHD: The Mediating Roles of Working Memory and Orthographic Conversion.

PubMed

Friedman, Lauren M; Rapport, Mark D; Raiker, Joseph S; Orban, Sarah A; Eckrich, Samuel J

2017-02-01

Reading comprehension difficulties in children with ADHD are well established; however, limited information exists concerning the cognitive mechanisms that contribute to these difficulties and the extent to which they interact with one another. The current study examines two broad cognitive processes known to be involved in children's reading comprehension abilities-(a) working memory (i.e., central executive processes [CE], phonological short-term memory [PH STM], and visuospatial short-term memory [VS STM]) and (b) orthographic conversion (i.e., conversion of visually presented text to a phonological code)-to elucidate their unique and interactive contribution to ADHD-related reading comprehension differences. Thirty-one boys with ADHD-combined type and 30 typically developing (TD) boys aged 8 to 12 years (M = 9.64, SD = 1.22) were administered multiple counterbalanced tasks assessing WM and orthographic conversion processes. Relative to TD boys, boys with ADHD exhibited significant deficits in PH STM (d = -0.70), VS STM (d = -0.92), CE (d = -1.58), and orthographic conversion (d = -0.93). Bias-corrected, bootstrapped mediation analyses revealed that CE and orthographic conversion processes modeled separately mediated ADHD-related reading comprehension differences partially, whereas PH STM and VS STM did not. CE and orthographic conversion modeled jointly mediated ADHD-related reading comprehension differences fully wherein orthographic conversion's large magnitude influence on reading comprehension occurred indirectly through CE's impact on the orthographic system. The findings suggest that adaptive cognitive interventions designed to improve reading-related outcomes in children with ADHD may benefit by including modules that train CE and orthographic conversion processes independently and interactively.

Timing in turn-taking and its implications for processing models of language

PubMed Central

Levinson, Stephen C.; Torreira, Francisco

2015-01-01

The core niche for language use is in verbal interaction, involving the rapid exchange of turns at talking. This paper reviews the extensive literature about this system, adding new statistical analyses of behavioral data where they have been missing, demonstrating that turn-taking has the systematic properties originally noted by Sacks et al. (1974; hereafter SSJ). This system poses some significant puzzles for current theories of language processing: the gaps between turns are short (of the order of 200 ms), but the latencies involved in language production are much longer (over 600 ms). This seems to imply that participants in conversation must predict (or ‘project’ as SSJ have it) the end of the current speaker’s turn in order to prepare their response in advance. This in turn implies some overlap between production and comprehension despite their use of common processing resources. Collecting together what is known behaviorally and experimentally about the system, the space for systematic explanations of language processing for conversation can be significantly narrowed, and we sketch some first model of the mental processes involved for the participant preparing to speak next. PMID:26124727

Feedstock Supply System Design and Economics for Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels Conversion Pathway: Fast Pyrolysis and Hydrotreating Bio-Oil Pathway "The 2017 Design Case"

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

Kevin L. Kenney; Kara G. Cafferty; Jacob J. Jacobson

The U.S. Department of Energy promotes the production of liquid fuels from lignocellulosic biomass feedstocks by funding fundamental and applied research that advances the state of technology in biomass sustainable supply, logistics, conversion, and overall system sustainability. As part of its involvement in this program, Idaho National Laboratory (INL) investigates the feedstock logistics economics and sustainability of these fuels. Between 2000 and 2012, INL quantified and the economics and sustainability of moving biomass from the field or stand to the throat of the conversion process using conventional equipment and processes. All previous work to 2012 was designed to improve themore » efficiency and decrease costs under conventional supply systems. The 2012 programmatic target was to demonstrate a biomass logistics cost of $55/dry Ton for woody biomass delivered to fast pyrolysis conversion facility. The goal was achieved by applying field and process demonstration unit-scale data from harvest, collection, storage, preprocessing, handling, and transportation operations into INL’s biomass logistics model.« less

Ultrafast Relaxation Dynamics of Photoexcited Zinc-Porphyrin: Electronic-Vibrational Coupling

DOE PAGES

Abraham, Baxter; Nieto-Pescador, Jesus; Gundlach, Lars

2016-08-02

Cyclic tetrapyrroles are the active core of compounds with crucial roles in living systems, such as hemoglobin and chlorophyll, and in technology as photocatalysts and light absorbers for solar energy conversion. Zinc-tetraphenylporphyrin (Zn-TPP) is a prototypical cyclic tetrapyrrole that has been intensely studied in past decades. Because of its importance for photochemical processes the optical properties are of particular interest, and, accordingly, numerous studies have focused on light absorption and excited-state dynamics of Zn-TPP. Relaxation after photoexcitation in the Soret band involves internal conversion that is preceded by an ultrafast process. This relaxation process has been observed by several groups.more » Until now, it has not been established if it involves a higher lying ”dark” state or vibrational relaxation in the excited S 2 state. Here we combine high time resolution electronic and vibrational spectroscopy to show that this process constitutes vibrational relaxation in the anharmonic 2 potential.« less

Ultrafast Relaxation Dynamics of Photoexcited Zinc-Porphyrin: Electronic-Vibrational Coupling

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

Abraham, Baxter; Nieto-Pescador, Jesus; Gundlach, Lars

Cyclic tetrapyrroles are the active core of compounds with crucial roles in living systems, such as hemoglobin and chlorophyll, and in technology as photocatalysts and light absorbers for solar energy conversion. Zinc-tetraphenylporphyrin (Zn-TPP) is a prototypical cyclic tetrapyrrole that has been intensely studied in past decades. Because of its importance for photochemical processes the optical properties are of particular interest, and, accordingly, numerous studies have focused on light absorption and excited-state dynamics of Zn-TPP. Relaxation after photoexcitation in the Soret band involves internal conversion that is preceded by an ultrafast process. This relaxation process has been observed by several groups.more » Until now, it has not been established if it involves a higher lying ”dark” state or vibrational relaxation in the excited S 2 state. Here we combine high time resolution electronic and vibrational spectroscopy to show that this process constitutes vibrational relaxation in the anharmonic 2 potential.« less

Isomolybdate conversion coatings

NASA Technical Reports Server (NTRS)

Minevski, Zoran (Inventor); Maxey, Jason (Inventor); Nelson, Carl (Inventor); Eylem, Cahit (Inventor)

2002-01-01

A conversion coating solution and process forms a stable and corrosion-resistant layer on metal substrates or layers or, more preferably, on a boehmite layer or other base conversion coating. The conversion coating process involves contacting the substrate, layer or coating with an aqueous alkali metal isomolybdate solution in order to convert the surface of the substrate, layer or coating to a stable conversion coating. The aqueous alkali metal molybdates are selected from sodium molybdate (Na.sub.2 MoO.sub.4), lithium molybdate (Li.sub.2 MoO.sub.4), potassium molybdate (K.sub.2 MoO.sub.4), or combinations thereof, with the most preferred alkali metal molybdate being sodium molybdate. The concentration of alkali metal molybdates in the solution is preferably less than 5% by weight. In addition to the alkali metal molybdates, the conversion coating solution may include alkaline metal passivators selected from lithium nitrate (LiNO.sub.3), sodium nitrate (NaNO.sub.3), ammonia nitrate (NH.sub.4 NO.sub.3), and combinations thereof; lithium chloride, potassium hexafluorozirconate (K.sub.2 ZrF.sub.6) or potassium hexafluorotitanate (K.sub.2 TiF.sub.6).

Testing of Environmentally Preferable Aluminum Pretreatments and Coating Systems for Use on Space Shuttle Solid Rocket Boosters (SRB)

NASA Technical Reports Server (NTRS)

Clayton, C.; Raley, R.; Zook, L.

2001-01-01

The solid rocket booster (SRB) has historically used a chromate conversion coating prior to protective finish application. After conversion coating, an organic paint system consisting of a chromated epoxy primer and polyurethane topcoat is applied. An overall systems approach was selected to reduce waste generation from the coatings application and removal processes. While the most obvious waste reduction opportunity involved elimination of the chromate conversion coating, several other coating system configurations were explored in an attempt to reduce the total waste. This paper will briefly discuss the use of a systems view to reduce waste generation from the coating process and present the results of the qualification testing of nonchromated aluminum pretreatments and alternate coating systems configurations.

First-principles quantum-mechanical investigations of biomass conversion at the liquid-solid interfaces

NASA Astrophysics Data System (ADS)

Dang, Hongli; Xue, Wenhua; Liu, Yingdi; Jentoft, Friederike; Resasco, Daniel; Wang, Sanwu

2014-03-01

We report first-principles density-functional calculations and ab initio molecular dynamics (MD) simulations for the reactions involving furfural, which is an important intermediate in biomass conversion, at the catalytic liquid-solid interfaces. The different dynamic processes of furfural at the water-Cu(111) and water-Pd(111) interfaces suggest different catalytic reaction mechanisms for the conversion of furfural. Simulations for the dynamic processes with and without hydrogen demonstrate the importance of the liquid-solid interface as well as the presence of hydrogen in possible catalytic reactions including hydrogenation and decarbonylation of furfural. Supported by DOE (DE-SC0004600). This research used the supercomputer resources of the XSEDE, the NERSC Center, and the Tandy Supercomputing Center.

CFD studies on biomass thermochemical conversion.

PubMed

Wang, Yiqun; Yan, Lifeng

2008-06-01

Thermochemical conversion of biomass offers an efficient and economically process to provide gaseous, liquid and solid fuels and prepare chemicals derived from biomass. Computational fluid dynamic (CFD) modeling applications on biomass thermochemical processes help to optimize the design and operation of thermochemical reactors. Recent progression in numerical techniques and computing efficacy has advanced CFD as a widely used approach to provide efficient design solutions in industry. This paper introduces the fundamentals involved in developing a CFD solution. Mathematical equations governing the fluid flow, heat and mass transfer and chemical reactions in thermochemical systems are described and sub-models for individual processes are presented. It provides a review of various applications of CFD in the biomass thermochemical process field.

CFD Studies on Biomass Thermochemical Conversion

PubMed Central

Wang, Yiqun; Yan, Lifeng

2008-01-01

Thermochemical conversion of biomass offers an efficient and economically process to provide gaseous, liquid and solid fuels and prepare chemicals derived from biomass. Computational fluid dynamic (CFD) modeling applications on biomass thermochemical processes help to optimize the design and operation of thermochemical reactors. Recent progression in numerical techniques and computing efficacy has advanced CFD as a widely used approach to provide efficient design solutions in industry. This paper introduces the fundamentals involved in developing a CFD solution. Mathematical equations governing the fluid flow, heat and mass transfer and chemical reactions in thermochemical systems are described and sub-models for individual processes are presented. It provides a review of various applications of CFD in the biomass thermochemical process field. PMID:19325848

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

Tan, Eric C. D.; Talmadge, Michael; Dutta, Abhijit

This report was developed as part of the U.S. Department of Energy’s Bioenergy Technologies Office’s (BETO’s) efforts to enable the development of technologies for the production of infrastructure-compatible, cost-competitive liquid hydrocarbon fuels from lignocellulosic biomass feedstocks. The research funded by BETO is designed to advance the state of technology of biomass feedstock supply and logistics, conversion, and overall system sustainability. It is expected that these research improvements will be made within the 2022 timeframe. As part of their involvement in this research and development effort, the National Renewable Energy Laboratory and the Pacific Northwest National Laboratory investigate the economics ofmore » conversion pathways through the development of conceptual biorefinery process models and techno-economic analysis models. This report describes in detail one potential conversion process for the production of high-octane gasoline blendstock via indirect liquefaction of biomass. The processing steps of this pathway include the conversion of biomass to synthesis gas or syngas via indirect gasification, gas cleanup, catalytic conversion of syngas to methanol intermediate, methanol dehydration to dimethyl ether (DME), and catalytic conversion of DME to high-octane, gasoline-range hydrocarbon blendstock product. The conversion process configuration leverages technologies previously advanced by research funded by BETO and demonstrated in 2012 with the production of mixed alcohols from biomass. Biomass-derived syngas cleanup via reforming of tars and other hydrocarbons is one of the key technology advancements realized as part of this prior research and 2012 demonstrations. The process described in this report evaluates a new technology area for the downstream utilization of clean biomass-derived syngas for the production of high-octane hydrocarbon products through methanol and DME intermediates. In this process, methanol undergoes dehydration to DME, which is subsequently converted via homologation reactions to high-octane, gasoline-range hydrocarbon products.« less

29 CFR 570.61 - Occupations in the operation of power-driven meat-processing machines and occupations involving...

Code of Federal Regulations, 2011 CFR

2011-07-01

... machines. (3) All occupations involved in tankage or rendering of dead animals, animal offal, animal fats..., and hashing machines; and presses (except belly-rolling machines). Except, the provisions of this.... Rendering plants means establishments engaged in the conversion of dead animals, animal offal, animal fats...

Involving consumers and the community in the development of a diagnostic instrument for fetal alcohol spectrum disorders in Australia

PubMed Central

2013-01-01

Background Australia’s commitment to consumer and community participation in health and medical research has grown over the past decade. Participatory research models of engagement are the most empowering for consumers. Methods As part of a project to develop a diagnostic instrument for fetal alcohol spectrum disorders (FASD) in Australia (FASD Project), the Australian FASD Collaboration (Collaboration), including a consumer advocate and two consumer representatives, was established. On completion of the FASD Project an on-line survey of Collaboration members was conducted to assess their views on consumer involvement. Women in the community were also invited to participate in Community Conversations to discuss real life situations regarding communications with health professionals about alcohol and pregnancy. Community Conversation feedback was analysed qualitatively and attendees were surveyed about their views of the Community Conversation process. Results The on-line survey was completed by 12 members of the Collaboration (71%). Consumer and community participation was considered important and essential, worked well, and was integral to the success of the project. The 32 women attending the Community Conversations generated 500 statements that made reference to prevention, how information and messages are delivered, and appropriate support for women. Nearly all the attendees at the Community Conversations (93%) believed that they had an opportunity to put forward their ideas and 96% viewed the Community Conversations as a positive experience. Conclusions The successful involvement of consumers and the community in the FASD Project can be attributed to active consumer and community participation, which included continued involvement throughout the project, funding of participation activities, and an understanding of the various contributions by the Collaboration members. PMID:23898969

Are Depictive Gestures like Pictures? Commonalities and Differences in Semantic Processing

ERIC Educational Resources Information Center

Wu, Ying Choon; Coulson, Seana

2011-01-01

Conversation is multi-modal, involving both talk and gesture. Does understanding depictive gestures engage processes similar to those recruited in the comprehension of drawings or photographs? Event-related brain potentials (ERPs) were recorded from neurotypical adults as they viewed spontaneously produced depictive gestures preceded by congruent…

Mistaken Identifiers: Gene name errors can be introduced inadvertently when using Excel in bioinformatics

PubMed Central

Zeeberg, Barry R; Riss, Joseph; Kane, David W; Bussey, Kimberly J; Uchio, Edward; Linehan, W Marston; Barrett, J Carl; Weinstein, John N

2004-01-01

Background When processing microarray data sets, we recently noticed that some gene names were being changed inadvertently to non-gene names. Results A little detective work traced the problem to default date format conversions and floating-point format conversions in the very useful Excel program package. The date conversions affect at least 30 gene names; the floating-point conversions affect at least 2,000 if Riken identifiers are included. These conversions are irreversible; the original gene names cannot be recovered. Conclusions Users of Excel for analyses involving gene names should be aware of this problem, which can cause genes, including medically important ones, to be lost from view and which has contaminated even carefully curated public databases. We provide work-arounds and scripts for circumventing the problem. PMID:15214961

Process for the conversion of carbonaceous feedstocks to particulate carbon and methanol

DOEpatents

Steinberg, Meyer; Grohse, Edward W.

1995-01-01

A process for the production of a pollutant-free particulate carbon (i.e., a substantially ash-, sulfur- and nitrogen-free carbon) from carbonaceous feedstocks. The basic process involves de-oxygenating one of the gas streams formed in a cyclic hydropyrolysis-methane pyrolysis process in order to improve conversion of the initial carbonaceous feedstock. De-oxygenation is effected by catalytically converting carbon monoxide, carbon dioxide, and hydrogen contained in one of the pyrolysis gas streams, preferably the latter, to a methanol co-product. There are thus produced two products whose use is known per se, viz., a substantially pollutant-free particulate carbon black and methanol. These products may be admixed in the form of a liquid slurry of carbon black in methanol.

Precursor engineering and controlled conversion for the synthesis of monodisperse thiolate-protected metal nanoclusters

NASA Astrophysics Data System (ADS)

Yu, Yong; Yao, Qiaofeng; Luo, Zhentao; Yuan, Xun; Lee, Jim Yang; Xie, Jianping

2013-05-01

In very recent years, thiolate-protected metal nanoclusters (or thiolated MNCs) with core sizes smaller than 2 nm have emerged as a new direction in nanoparticle research due to their discrete and size dependent electronic structures and molecular-like properties, such as HOMO-LUMO transitions in optical absorptions, quantized charging, and strong luminescence. Synthesis of monodisperse thiolated MNCs in sufficiently large quantities (up to several hundred micrograms) is necessary for establishing reliable size-property relationships and exploring potential applications. This Feature Article reviews recent progress in the development of synthetic strategies for the production of monodisperse thiolated MNCs. The preparation of monodisperse thiolated MNCs is viewed as an engineerable process where both the precursors (input) and their conversion chemistry (processing) may be rationally designed to achieve the desired outcome - monodisperse thiolated MNCs (output). Several strategies for tailoring the precursor and the conversion process are analyzed to arrive at a unifying understanding of the processes involved.

Structural basis of sodium–potassium exchange of a human telomeric DNA quadruplex without topological conversion

PubMed Central

Wang, Zi-Fu; Li, Ming-Hao; Hsu, Shang-Te Danny; Chang, Ta-Chau

2014-01-01

Understanding the mechanism of Na+/K+-dependent spectral conversion of human telomeric G-quadruplex (G4) sequences has been limited not only because of the structural polymorphism but also the lack of sufficient structural information at different stages along the conversion process for one given oligonucleotide. In this work, we have determined the topology of the Na+ form of Tel23 G4, which is the same hybrid form as the K+ form of Tel23 G4 despite the distinct spectral patterns in their respective nuclear magnetic resonance (NMR) and circular dichroism spectra. The spectral difference, particularly the well-resolved imino proton NMR signals, allows us to monitor the structural conversion from Na+ form to K+ form during Na+/K+ exchange. Time-resolved NMR experiments of hydrogen–deuterium exchange and hybridization clearly exclude involvement of the global unfolding for the fast Na+/K+ spectral conversion. In addition, the K+ titration monitored by NMR reveals that the Na+/K+ exchange in Tel23 G4 is a two-step process. The addition of K+ significantly stabilizes the unfolding kinetics of Tel23 G4. These results offer a possible explanation of rapid spectral conversion of Na+/K+ exchange and insight into the mechanism of Na+/K+ structural conversion in human telomeric G4s. PMID:24476914

Intellectual Interest Mediates Gene x Socioeconomic Status Interaction on Adolescent Academic Achievement

ERIC Educational Resources Information Center

Tucker-Drob, Elliot M.; Harden, K. Paige

2012-01-01

Recent studies have demonstrated that genetic influences on cognitive ability and academic achievement are larger for children raised in higher socioeconomic status (SES) homes. However, little work has been done to document the psychosocial processes that underlie this Gene x Environment interaction. One process may involve the conversion of…

7 CFR 3560.402 - Loan payment processing.

Code of Federal Regulations, 2010 CFR

2010-01-01

... paragraph (c) of this section, must be closed and serviced using the PASS. (b) Required conversion to PASS... action on the account involves a change in the loan rates or terms or whenever a subsequent loan to the...

Syntax and conversation in aphasia. A strategic restrictive use of Spanish and Catalan connector QUE by aphasic speakers.

PubMed

Hernández-Sacristán, Carlos; Rosell-Clari, Vicent

2009-10-01

Oral conversational data are deemed to be a relevant empirical source when it comes to formulating and supporting hypotheses about cognitive processes involved in aphasic linguistic production. With this assumption in mind, free conversational uses of the Spanish and Catalan connector QUE by fluent and non-fluent aphasic speakers are examined by contrasting them with normal speakers' (i.e. conversational partners') productions. Strictly ungrammatical uses in aphasic speakers are practically non-existent in free conversation. Nevertheless, this data permits one to characterize the aphasic production of the morpheme QUE as restrictive--to different degrees--with respect to normal production. Moreover, this restriction, selectively affecting the types of syntactic environments examined, can be considered strategic in nature: it is guided by some kind of knowledge about the administration of remnant linguistic resources.

Techno-economic analysis of a biomass depot

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

Jacobson, Jacob Jordan; Lamers, Patrick; Roni, Mohammad Sadekuzzaman

2014-10-01

The U.S. Department of Energy (DOE) Bioenergy Technologies Office (BETO) promotes the production of an array of liquid fuels and fuel blendstocks from lignocellulosic biomass feedstocks by funding fundamental and applied research that advances the state of technology in biomass collection, conversion, and sustainability. As part of its involvement in this program, the Idaho National Laboratory (INL) investigates the technical, economic, and environmental performance of different feedstock supply systems and their impacts on the downstream conversion processes.

Potential and challenges of zeolite chemistry in the catalytic conversion of biomass.

PubMed

Ennaert, Thijs; Van Aelst, Joost; Dijkmans, Jan; De Clercq, Rik; Schutyser, Wouter; Dusselier, Michiel; Verboekend, Danny; Sels, Bert F

2016-02-07

Increasing demand for sustainable chemicals and fuels has pushed academia and industry to search for alternative feedstocks replacing crude oil in traditional refineries. As a result, an immense academic attention has focused on the valorisation of biomass (components) and derived intermediates to generate valuable platform chemicals and fuels. Zeolite catalysis plays a distinct role in many of these biomass conversion routes. This contribution emphasizes the progress and potential in zeolite catalysed biomass conversions and relates these to concepts established in existing petrochemical processes. The application of zeolites, equipped with a variety of active sites, in Brønsted acid, Lewis acid, or multifunctional catalysed reactions is discussed and generalised to provide a comprehensive overview. In addition, the feedstock shift from crude oil to biomass involves new challenges in developing fields, like mesoporosity and pore interconnectivity of zeolites and stability of zeolites in liquid phase. Finally, the future challenges and perspectives of zeolites in the processing of biomass conversion are discussed.

Superacid Catalyzed Coal Conversion Chemistry. 1st and 2nd Quarterly Technical Progress Reports, September 1, 1983-March 30, 1984.

DOE R&D Accomplishments Database

Olah, G. A.

1984-01-01

In our laboratories we have previously developed a mild coal conversion process. This involves the use of a superacid system consisting of HF and BF{sub 3} in presence of hydrogen and/or a hydrogen donor solvent. In order to understand the chemistry involved in the process of depolymerization of coal by the HF:BF{sub 3}:H{sub 2} system we are carrying out a systematic study of a number of coal model compounds. The model compounds selected for present study have two benzene rings connected with various bridging units such as alkylidene, ether, sulfide etc. From studies so far carried out it appears that high pyridine extractibilities achieved by treating coal at temperature below 100 degrees C results from the cleavage of bridges such as present in bibenzyl, diphenyl methane, dibenzyl ether, dibenzyl sulfide etc. On the other hand the increased cyclohexane extractibility and distillability observed at relatively higher temperatures and hydrogen pressures reflects the hydrogenation and cleavage of the aromatic backbone in coal structure similar to what is seen in the conversion of model compounds such as biphenyl, diphenyl ether, diphenyl sulfide, anthracene, etc.

Process for the conversion of carbonaceous feedstocks to particulate carbon and methanol

DOEpatents

Steinberg, M.; Grohse, E.W.

1995-06-27

A process is described for the production of a pollutant-free particulate carbon (i.e., a substantially ash-, sulfur- and nitrogen-free carbon) from carbonaceous feedstocks. The basic process involves de-oxygenating one of the gas streams formed in a cyclic hydropyrolysis-methane pyrolysis process in order to improve conversion of the initial carbonaceous feedstock. De-oxygenation is effected by catalytically converting carbon monoxide, carbon dioxide, and hydrogen contained in one of the pyrolysis gas streams, preferably the latter, to a methanol co-product. There are thus produced two products whose use is known per se, viz., a substantially pollutant-free particulate carbon black and methanol. These products may be admixed in the form of a liquid slurry of carbon black in methanol. 3 figs.

Artifacts Of Spectral Analysis Of Instrument Readings

NASA Technical Reports Server (NTRS)

Wise, James H.

1995-01-01

Report presents experimental and theoretical study of some of artifacts introduced by processing outputs of two nominally identical low-frequency-reading instruments; high-sensitivity servo-accelerometers mounted together and operating, in conjunction with signal-conditioning circuits, as seismometers. Processing involved analog-to-digital conversion with anti-aliasing filtering, followed by digital processing including frequency weighting and computation of different measures of power spectral density (PSD).

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

Underwood, R.P.

As part of the DOE-sponsored contract Synthesis of Dimethyl Ether and Alternative Fuels in the Liquid Phase from Coal-Derived Syngas'' experimental evaluations of the one-step synthesis of alternative fuels were carried out. The objective of this work was to develop novel processes for converting coal-derived syngas to fuels or fuel additives. Building on a technology base acquired during the development of the Liquid Phase Methanol (LPMEOH) process, this work focused on the development of slurry reactor based processes. The experimental investigations, which involved bench-scale reactor studies, focused primarily on three areas: (1) One-step, slurry-phase syngas conversion to hydrocarbons or methanol/hydrocarbonmore » mixtures using a mixture of methanol synthesis catalyst and methanol conversion catalyst in the same slurry reactor. (2) Slurry-phase conversion of syngas to mixed alcohols using various catalysts. (3) One-step, slurry-phase syngas conversion to mixed ethers using a mixture of mixed alcohols synthesis catalyst and dehydration catalyst in the same slurry reactor. The experimental results indicate that, of the three types of processes investigated, slurry phase conversion of syngas to mixed alcohols shows the most promise for further process development. Evaluations of various mixed alcohols catalysts show that a cesium-promoted Cu/ZnO/Al[sub 2]O[sub 3] methanol synthesis catalyst, developed in Air Products' laboratories, has the highest performance in terms of rate and selectivity for C[sub 2+]-alcohols. In fact, once-through conversion at industrially practical reaction conditions yielded a mixed alcohols product potentially suitable for direct gasoline blending. Moreover, an additional attractive aspect of this catalyst is its high selectivity for branched alcohols, potential precursors to iso-olefins for use in etherification.« less

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

Underwood, R.P.

As part of the DOE-sponsored contract ``Synthesis of Dimethyl Ether and Alternative Fuels in the Liquid Phase from Coal-Derived Syngas`` experimental evaluations of the one-step synthesis of alternative fuels were carried out. The objective of this work was to develop novel processes for converting coal-derived syngas to fuels or fuel additives. Building on a technology base acquired during the development of the Liquid Phase Methanol (LPMEOH) process, this work focused on the development of slurry reactor based processes. The experimental investigations, which involved bench-scale reactor studies, focused primarily on three areas: (1) One-step, slurry-phase syngas conversion to hydrocarbons or methanol/hydrocarbonmore » mixtures using a mixture of methanol synthesis catalyst and methanol conversion catalyst in the same slurry reactor. (2) Slurry-phase conversion of syngas to mixed alcohols using various catalysts. (3) One-step, slurry-phase syngas conversion to mixed ethers using a mixture of mixed alcohols synthesis catalyst and dehydration catalyst in the same slurry reactor. The experimental results indicate that, of the three types of processes investigated, slurry phase conversion of syngas to mixed alcohols shows the most promise for further process development. Evaluations of various mixed alcohols catalysts show that a cesium-promoted Cu/ZnO/Al{sub 2}O{sub 3} methanol synthesis catalyst, developed in Air Products` laboratories, has the highest performance in terms of rate and selectivity for C{sub 2+}-alcohols. In fact, once-through conversion at industrially practical reaction conditions yielded a mixed alcohols product potentially suitable for direct gasoline blending. Moreover, an additional attractive aspect of this catalyst is its high selectivity for branched alcohols, potential precursors to iso-olefins for use in etherification.« less

Mechanism of wavelength conversion in polystyrene doped with benzoxanthene: emergence of a complex.

PubMed

Nakamura, Hidehito; Shirakawa, Yoshiyuki; Kitamura, Hisashi; Sato, Nobuhiro; Shinji, Osamu; Saito, Katashi; Takahashi, Sentaro

2013-01-01

Fluorescent guest molecules doped in polymers have been used to convert ultraviolet light into visible light for applications ranging from optical fibres to filters for the cultivation of plants. The wavelength conversion process involves the absorption of light at short wavelengths followed by fluorescence emission at a longer wavelength. However, a precise understanding of the light conversion remains unclear. Here we show light responses for a purified polystyrene base substrates doped with fluorescent benzoxanthene in concentrations varied over four orders of magnitude. The shape of the excitation spectrum for fluorescence emission changes significantly with the concentration of the benzoxanthene, indicating formation of a base substrate/fluorescent molecule complex. Furthermore, the wavelength conversion light yield increases in three stages depending on the nature of the complex. These findings identify a mechanism that will have many applications in wavelength conversion materials.

Mechanism of wavelength conversion in polystyrene doped with benzoxanthene: emergence of a complex

PubMed Central

Nakamura, Hidehito; Shirakawa, Yoshiyuki; Kitamura, Hisashi; Sato, Nobuhiro; Shinji, Osamu; Saito, Katashi; Takahashi, Sentaro

2013-01-01

Fluorescent guest molecules doped in polymers have been used to convert ultraviolet light into visible light for applications ranging from optical fibres to filters for the cultivation of plants. The wavelength conversion process involves the absorption of light at short wavelengths followed by fluorescence emission at a longer wavelength. However, a precise understanding of the light conversion remains unclear. Here we show light responses for a purified polystyrene base substrates doped with fluorescent benzoxanthene in concentrations varied over four orders of magnitude. The shape of the excitation spectrum for fluorescence emission changes significantly with the concentration of the benzoxanthene, indicating formation of a base substrate/fluorescent molecule complex. Furthermore, the wavelength conversion light yield increases in three stages depending on the nature of the complex. These findings identify a mechanism that will have many applications in wavelength conversion materials. PMID:23974205

Ionic Liquids in Biomass Processing

NASA Astrophysics Data System (ADS)

Tan, Suzie Su Yin; Macfarlane, Douglas R.

Ionic liquids have been studied for their special solvent properties in a wide range of processes, including reactions involving carbohydrates such as cellulose and glucose. Biomass is a widely available and renewable resource that is likely to become an economically viable source of starting materials for chemical and fuel production, especially with the price of petroleum set to increase as supplies are diminished. Biopolymers such as cellulose, hemicellulose and lignin may be converted to useful products, either by direct functionalisation of the polymers or depolymerisation to monomers, followed by microbial or chemical conversion to useful chemicals. Major barriers to the effective conversion of biomass currently include the high crystallinity of cellulose, high reactivity of carbohydrates and lignin, insolubility of cellulose in conventional solvents, as well as heterogeneity in the native lignocellulosic materials and in lignin itself. This combination of factors often results in highly heterogeneous depolymerisation products, which make efficient separation difficult. Thus the extraction, depolymerisation and conversion of biopolymers will require novel reaction systems in order to be both economically attractive and environmentally benign. The solubility of biopolymers in ionic liquids is a major advantage of their use, allowing homogeneous reaction conditions, and this has stimulated a growing research effort in this field. This review examines current research involving the use of ionic liquids in biomass reactions, with perspectives on how it relates to green chemistry, economic viability, and conventional biomass processes.

Improvement of ethanol yield from glycerol via conversion of pyruvate to ethanol in metabolically engineered Saccharomyces cerevisiae.

PubMed

Yu, Kyung Ok; Jung, Ju; Ramzi, Ahmad Bazli; Kim, Seung Wook; Park, Chulhwan; Han, Sung Ok

2012-02-01

The conversion of low-priced glycerol to higher value products has been proposed as a way to improve the economic viability of the biofuels industry. In a previous study, the conversion of glycerol to ethanol in a metabolically engineered strain of Saccharomyces cerevisiae was accomplished by minimizing the synthesis of glycerol, the main by-product in ethanol fermentation processing. To further improve ethanol production, overexpression of the native genes involved in conversion of pyruvate to ethanol in S. cerevisiae was successfully accomplished. The overexpression of an alcohol dehydrogenase (adh1) and a pyruvate decarboxylase (pdc1) caused an increase in growth rate and glycerol consumption under fermentative conditions, which led to a slight increase of the final ethanol yield. The overall expression of the adh1 and pdc1 genes in the modified strains, combined with the lack of the fps1 and gpd2 genes, resulted in a 1.4-fold increase (about 5.4 g/L ethanol produced) in fps1Δgpd2Δ (pGcyaDak, pGupCas) (about 4.0 g/L ethanol produced). In summary, it is possible to improve the ethanol yield by overexpression of the genes involved in the conversion of pyruvate to ethanol in engineered S. cerevisiae using glycerol as substrate.

Commercialization of waste gob gas and methane produced in conjunction with coal mining operations. Final report, August 1992--December 1993

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

Not Available

1993-12-01

The primary objectives of the project were to identify and evaluate existing processes for (1) using gas as a feedstock for production of marketable, value-added commodities, and (2) enriching contaminated gas to pipeline quality. The following gas conversion technologies were evaluated: (1) transformation to liquid fuels, (2) manufacture of methanol, (3) synthesis of mixed alcohols, and (4) conversion to ammonia and urea. All of these involved synthesis gas production prior to conversion to the desired end products. Most of the conversion technologies evaluated were found to be mature processes operating at a large scale. A drawback in all of themore » processes was the need to have a relatively pure feedstock, thereby requiring gas clean-up prior to conversion. Despite this requirement, the conversion technologies were preliminarily found to be marginally economic. However, the prohibitively high investment for a combined gas clean-up/conversion facility required that REI refocus the project to investigation of gas enrichment alternatives. Enrichment of a gas stream with only one contaminant is a relatively straightforward process (depending on the contaminant) using available technology. However, gob gas has a unique nature, being typically composed of from constituents. These components are: methane, nitrogen, oxygen, carbon dioxide and water vapor. Each of the four contaminants may be separated from the methane using existing technologies that have varying degrees of complexity and compatibility. However, the operating and cost effectiveness of the combined system is dependent on careful integration of the clean-up processes. REI is pursuing Phase 2 of this project for demonstration of a waste gas enrichment facility using the approach described above. This is expected to result in the validation of the commercial and technical viability of the facility, and the refinement of design parameters.« less

Localised and delocalised optically induced conversion of composite glow peak 5 in LiF:Mg,Ti (TLD-100) to glow peak 4 as a function of postirradiation annealing temperature.

PubMed

Horowitz, Y S; Einav, Y; Biderman, S; Oster, L

2002-01-01

The composite structure of glow peak 5 in LiF:Mg,Ti (TLD-100) has been investigated using optical bleaching by 310 nm (4 eV) light. The glow peak conversion efficiency of peak 5a (Tm = 187 degrees C) to peak 4 traps is very high at a value of 3+/-0.5 (1 SD) whereas the glow peak conversion efficiency of peak 5 (Tm = 205 degrees C) to peak 4 traps is 0.0026+/-0.0012 (1 SD). The high conversion efficiency of peak 5a to peak 4 arises from direct optical ionisation of the electron in the electron-hole pair. leaving behind a singly-trapped hole (peak 4), a direct mechanism, relatively free of competitive mechanisms. Optical ionisation of the 'singly-trapped' electron (peak 5), however, can lead to peak 4 only via multi-stage mechanisms involving charge carrier transport in the valence and conduction bands, a mechanism subject to competitive processes. The conduction/valence band competitive processes lead to the factor of one thousand decrease in the conversion efficiency of peak 5 compared to peak 5a.

Launcher Roadmap for the CrVI Substitution of Surface Treatments. Screening of Trivalent-Chromium Conversion Solutions and First Promising Results for Repair Applications on Aluminium Alloys

NASA Astrophysics Data System (ADS)

Debout, Vincent; Pettier, Sophie

2014-06-01

Airbus Defence and Space, Space System is involved in a global roadmap for launchers in order to substitute hexavalent chromium (CrVI) and Cadmium in the current surface treatments on metallic structures.Within this framework, a screening of trivalent chromium (CrIII) conversion solutions for touch-up applications has been carried out since this step is crucial to perform local application or to repair minor damages on launcher structures but it leads to higher risks of exposure for the workers.Three commercial CrIII conversion solutions have been evaluated on high performance aluminum alloys such as AA2024 T3 and AA7175 T7351 that are often used as structural materials.This preliminary investigation highlights the effect of surface preparation, rinsing and conversion process on the final corrosion performance of conversion coatings (CCs). The results are also discussed in terms of visual aspect and adhesion with new Cr-free primers.Two operating sets of parameters are identified with promising results that represent the first steps towards the development of a new Cr-free touch-up process.

Simulating the conversion of rural settlements to town land based on multi-agent systems and cellular automata.

PubMed

Liu, Yaolin; Kong, Xuesong; Liu, Yanfang; Chen, Yiyun

2013-01-01

Rapid urbanization in China has triggered the conversion of land from rural to urban use, particularly the conversion of rural settlements to town land. This conversion is the result of the joint effects of the geographic environment and agents involving the government, investors, and farmers. To understand the dynamic interaction dominated by agents and to predict the future landscape of town expansion, a small town land-planning model is proposed based on the integration of multi-agent systems (MAS) and cellular automata (CA). The MAS-CA model links the decision-making behaviors of agents with the neighbor effect of CA. The interaction rules are projected by analyzing the preference conflicts among agents. To better illustrate the effects of the geographic environment, neighborhood, and agent behavior, a comparative analysis between the CA and MAS-CA models in three different towns is presented, revealing interesting patterns in terms of quantity, spatial characteristics, and the coordinating process. The simulation of rural settlements conversion to town land through modeling agent decision and human-environment interaction is very useful for understanding the mechanisms of rural-urban land-use change in developing countries. This process can assist town planners in formulating appropriate development plans.

Up-conversion luminescence of Er3+ ions in lead-free germanate glasses under 800 nm and 980 nm cw diode laser excitation

NASA Astrophysics Data System (ADS)

Janek, J.; Lisiecki, R.; Ryba-Romanowski, W.; Pisarska, J.; Pisarski, W. A.

2017-12-01

Up-conversion luminescence spectra of Er3+ ions in multicomponent oxyfluoride glasses GeO2 - BaO - BaF2 - Ga2O3 - Er2O3 were examined. It was found that the up-conversion luminescence spectra of Er3+ are dependent on pumping wavelengths. The spectra recorded upon the excitation at 800 nm contained an intense green up-conversion luminescence corresponding to the 2H11/2,4S3/2 → 4I15/2 transitions and a very weak red luminescence related to the 4F9/2 - 4I15/2 transition. In spectra recorded upon 980 nm excitation the contribution of the red luminescence was markedly higher. The interaction mechanisms involved in up-conversion processes are proposed and observed dependence of intensity of up-converted luminescence on excitation power is discussed. The experimental results suggest that Er3+ singly doped lead-free oxyfluoride germanate glass is useful for up-conversion luminescence applications.

Analysis of STAT laboratory turnaround times before and after conversion of the hospital information system.

PubMed

Lowe, Gary R; Griffin, Yolanda; Hart, Michael D

2014-08-01

Modern electronic health record systems (EHRS) reportedly offer advantages including improved quality, error prevention, cost reduction, and increased efficiency. This project reviewed the impact on specimen turnaround times (TAT) and percent compliance for specimens processed in a STAT laboratory after implementation of an upgraded EHRS. Before EHRS implementation, laboratory personnel received instruction and training for specimen processing. One laboratory member per shift received additional training. TAT and percent compliance data sampling occurred 4 times monthly for 13 months post-conversion and were compared with the mean of data collected for 3 months pre-conversion. Percent compliance was gauged using a benchmark of reporting 95% of all specimens within 7 min from receipt. Control charts were constructed for TAT and percent compliance with control limits set at 2 SD and applied continuously through the data collection period. TAT recovered to pre-conversion levels by the 6th month post-conversion. Percent compliance consistently returned to pre-conversion levels by the 10th month post-conversion. Statistical analyses revealed the TAT were significantly longer for 3 months post-conversion (P < .001) compared with pre-conversion levels. Statistical significance was not observed for subsequent groups. Percent compliance results were significantly lower for 6 months post-conversion (P < .001). Statistical significance was not observed for subsequent groups. Extensive efforts were made to train and prepare personnel for challenges expected after the EHRS upgrade. Specific causes identified with the upgraded EHRS included multiple issues involving personnel and the EHRS. These data suggest that system and user issues contributed to delays in returning to pre-conversion TAT and percent compliance levels following the upgrade in the EHRS.

Laser synthesized super-hydrophobic conducting carbon with broccoli-type morphology as a counter-electrode for dye sensitized solar cells

NASA Astrophysics Data System (ADS)

Gokhale, Rohan; Agarkar, Shruti; Debgupta, Joyashish; Shinde, Deodatta; Lefez, Benoit; Banerjee, Abhik; Jog, Jyoti; More, Mahendra; Hannoyer, Beatrice; Ogale, Satishchandra

2012-10-01

A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode.A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode. Electronic supplementary information (ESI) available: Materials and equipment details, solar cell fabrication protocol, electrolyte spreading time measurement details, XPS spectra, electronic study, film adhesion test detailed analysis and field emission results. See DOI: 10.1039/c2nr32082g

Bioinspired catalytic materials for energy-relevant conversions

NASA Astrophysics Data System (ADS)

Artero, Vincent

2017-09-01

The structure of active sites of enzymes involved in bioenergetic processes can inspire design of active, stable and cost-effective catalysts for renewable-energy technologies. For these materials to reach maturity, the benefits of bioinspired systems must be combined with practical technological requirements.

Accumulation of Citrulline by Microbial Arginine Metabolism during Alcoholic Fermentation of Soy Sauce.

PubMed

Fang, Fang; Zhang, Jiran; Zhou, Jingwen; Zhou, Zhaohui; Li, Tieqiao; Lu, Liling; Zeng, Weizhu; Du, Guocheng; Chen, Jian

2018-03-07

Citrulline, the major precursor of ethyl carbamate in soy sauce, is an intermediate catabolite of arginine produced by bacteria present in soy sauce moromi mash. Pediococcus acidilactici is responsible for the formation of citrulline during the lactic acid fermentation process of soy sauce. However, citrulline accumulation during the alcoholic fermentation process and the corresponding bacteria involved have not been identified. Salt-tolerant, arginine-utilizing bacteria were isolated from moromi mash during the alcoholic fermentation process. Under normal cultivation conditions, arginine utilization by these strains did not contribute to citrulline accumulation. However, the conversion of arginine to citrulline by these bacteria increased when cultivated during the alcoholic fermentation process. Additionally, the ethanol-enhanced solubility of free fatty acids in moromi mash stimulated the accumulation of citrulline. Staphylococcus exhibited the highest capability in the conversion of arginine to citrulline.

A mild thermomechanical process for the enzymatic conversion of radiata pine into fermentable sugars and lignin.

PubMed

Suckling, Ian D; Jack, Michael W; Lloyd, John A; Murton, Karl D; Newman, Roger H; Stuthridge, Trevor R; Torr, Kirk M; Vaidya, Alankar A

2017-01-01

Conversion of softwoods into sustainable fuels and chemicals is important for parts of the world where softwoods are the dominant forest species. While they have high theoretical sugar yields, softwoods are amongst the most recalcitrant feedstocks for enzymatic processes, typically requiring both more severe pretreatment conditions and higher enzyme doses than needed for other lignocellulosic feedstocks. Although a number of processes have been proposed for converting softwoods into sugars suitable for fuel and chemical production, there is still a need for a high-yielding, industrially scalable and cost-effective conversion route. We summarise work leading to the development of an efficient process for the enzymatic conversion of radiata pine ( Pinus radiata ) into wood sugars. The process involves initial pressurised steaming of wood chips under relatively mild conditions (173 °C for 3-72 min) without added acid catalyst. The steamed chips then pass through a compression screw to squeeze out a pressate rich in solubilised hemicelluloses. The pressed chips are disc-refined and wet ball-milled to produce a substrate which is rapidly saccharified using commercially available enzyme cocktails. Adding 0.1% polyethylene glycol during saccharification was found to be particularly effective with these substrates, reducing enzyme usage to acceptable levels, e.g. 5 FPU/g OD substrate. The pressate is separately hydrolysed using acid, providing additional hemicellulose-derived sugars, for an overall sugar yield of 535 kg/ODT chips (76% of theoretical). The total pretreatment energy input is comparable to other processes, with the additional energy for attrition being balanced by a lower thermal energy requirement. This pretreatment strategy produces substrates with low levels of fermentation inhibitors, so the glucose-rich mainline and pressate syrups can be fermented to ethanol without detoxification. The lignin from the process remains comparatively unmodified, as evident from the level of retained β-ether interunit linkages, providing an opportunity for conversion into saleable co-products. This process is an efficient route for the enzymatic conversion of radiata pine, and potentially other softwoods, into a sugar syrup suitable for conversion into fuels and chemicals. Furthermore, the process uses standard equipment that is largely proven at commercial scale, de-risking process scale-up.

Enantioselective production of benzoin from benzoin acetate via kinetic resolution and deracemization using Rhizopus oryzae.

PubMed

Songür, Rahime; Lurçi, Binnaz; Bayraktar, Emine; Mehmetoğlu, Ulkü; Demir, Ayhan S

2011-06-01

In this study, the production of enantiopure benzoin from rac-benzoin acetate was achieved by lipase catalyzed kinetic resolution combined with deracemization using Rhizopus oryzae (CBS111718). The growth cells were pretreated with 20 kHz and 30 kHz ultrasound irradiation and mechanical homogenization. Approximately 100% conversion and 96% enantiomeric excess of the product (S-benzoin) were obtained by applying 20 kHz ultrasound irradiation at pH 6. The deracemization process involves new and important processes that allow for the transformation of a racemate into a single stereoisomeric product in 100% theoretical yields. Moreover, the application of ultrasound increases the conversion rate by reducing mass transfer limitation.

Recent progress in solution plasma-synthesized-carbon-supported catalysts for energy conversion systems

NASA Astrophysics Data System (ADS)

Lun Li, Oi; Lee, Hoonseung; Ishizaki, Takahiro

2018-01-01

Carbon-based materials have been widely utilized as the electrode materials in energy conversion and storage technologies, such as fuel cells and metal-air batteries. In these systems, the oxygen reduction reaction is an important step that determines the overall performance. A novel synthesis route, named the solution plasma process, has been recently utilized to synthesize various types of metal-based and heteroatom-doped carbon catalysts. In this review, we summarize cutting-edge technologies involving the synthesis and modeling of carbon-supported catalysts synthesized via solution plasma process, followed by current progress on the electrocatalytic performance of these catalysts. This review provides the fundamental and state-of-the-art performance of solution-plasma-synthesized electrode materials, as well as the remaining scientific and technological challenges for this process.

Effects of Real-Time Cochlear Implant Simulation on Speech Perception and Production

ERIC Educational Resources Information Center

Casserly, Elizabeth D.

2013-01-01

Real-time use of spoken language is a fundamentally interactive process involving speech perception, speech production, linguistic competence, motor control, neurocognitive abilities such as working memory, attention, and executive function, environmental noise, conversational context, and--critically--the communicative interaction between…

Effective Charge Carrier Utilization in Photocatalytic Conversions.

PubMed

Zhang, Peng; Wang, Tuo; Chang, Xiaoxia; Gong, Jinlong

2016-05-17

Continuous efforts have been devoted to searching for sustainable energy resources to alleviate the upcoming energy crises. Among various types of new energy resources, solar energy has been considered as one of the most promising choices, since it is clean, sustainable, and safe. Moreover, solar energy is the most abundant renewable energy, with a total power of 173 000 terawatts striking Earth continuously. Conversion of solar energy into chemical energy, which could potentially provide continuous and flexible energy supplies, has been investigated extensively. However, the conversion efficiency is still relatively low since complicated physical, electrical, and chemical processes are involved. Therefore, carefully designed photocatalysts with a wide absorption range of solar illumination, a high conductivity for charge carriers, a small number of recombination centers, and fast surface reaction kinetics are required to achieve a high activity. This Account describes our recent efforts to enhance the utilization of charge carriers for semiconductor photocatalysts toward efficient solar-to-chemical energy conversion. During photocatalytic reactions, photogenerated electrons and holes are involved in complex processes to convert solar energy into chemical energy. The initial step is the generation of charge carriers in semiconductor photocatalysts, which could be enhanced by extending the light absorption range. Integration of plasmonic materials and introduction of self-dopants have been proved to be effective methods to improve the light absorption ability of photocatalysts to produce larger amounts of photogenerated charge carriers. Subsequently, the photogenerated electrons and holes migrate to the surface. Therefore, acceleration of the transport process can result in enhanced solar energy conversion efficiency. Different strategies such as morphology control and conductivity improvement have been demonstrated to achieve this goal. Fine-tuning of the morphology of nanostructured photocatalysts can reduce the migration distance of charge carriers. Improving the conductivity of photocatalysts by using graphitic materials can also improve the transport of charge carriers. Upon charge carrier migration, electrons and holes also tend to recombine. The suppression of recombination can be achieved by constructing heterojunctions that enhance charge separation in the photocatalysts. Surface states acting as recombination centers should also be removed to improve the photocatalytic efficiency. Moreover, surface reactions, which are the core chemical processes during the solar energy conversion, can be enhanced by applying cocatalysts as well as suppressing side reactions. All of these strategies have been proved to be essential for enhancing the activities of semiconductor photocatalysts. It is hoped that delicate manipulation of photogenerated charge carriers in semiconductor photocatalysts will hold the key to effective solar-to-chemical energy conversion.

Converting Y(OH){sub 3} nanofiber bundles to YVO{sub 4} polyhedrons for photodegradation of dye contaminants

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

Li, Li; School of Chemical Engineering and Materials Engineering, Huainan Normal University, Huainan 232038; Zou, Lei

2015-08-15

Highlights: • YVO{sub 4} polyhedrons were prepared from Y(OH){sub 3} nanofiber bundles through a hydrothermal conversion process. • In contrast to the bulk oxide, the photocatalytic performance of the polyhedrons was much improved. • The main active species involved in photocatalytic oxidative reaction were also investigated. - Abstract: This paper reports a hydrothermal conversion process of rare earth microstructures, Y(OH){sub 3} nanofiber bundles, into YVO{sub 4} polyhedrons, together with the investigation on the related photocatalytic properties. The as-synthesized samples were characterized by a variety of techniques, including XRD, SEM, TEM and UV–vis diffuse reflectance spectroscopy. The photocatalytic activities of YVO{submore » 4} polyhedrons were comparatively evaluated by the photodegradation of Rhodamine B and methylene blue. In contrast to the bulk oxide, the photocatalytic performance of the polyhedrons was much improved. The mechanism and the main active species involved in photocatalytic oxidative reaction were also investigated through the carriers trapping experiments.« less

Lexical Cues of Interaction Involvement in Dyadic Instant Messaging Conversations

ERIC Educational Resources Information Center

Nguyen, Duyen T.; Fussell, Susan R.

2014-01-01

We explore how people express and interpret lexical cues of interaction involvement in dyadic conversations via instant messaging (IM) in two studies. In Study 1, an experiment with 60 participants, we manipulated level of involvement in a conversation with a distraction task. We examined how participants' uses of verbal cues such as pronouns…

Morphology-preserving chemical conversion of bioorganic and inorganic templates

NASA Astrophysics Data System (ADS)

Vernon, Jonathan Paul

The generation of nanostructured assemblies with complex (three-dimensional, 3D) self-assembled morphologies and with complex (multicomponent) tailorable inorganic compositions is of considerable technological and scientific interest. This dissertation demonstrates self-assembled 3D organic templates of biogenic origin can be converted into replicas comprised of numerous other functional nanocrystalline inorganic materials. Nature provides a spectacular variety of biologically-assembled 3D organic structures with intricate, hierarchical (macro-to-micro-to-nanoscale) morphologies. Such processing on readily-available structurally complex templates provides a framework for chemical conversion of synthetic organic templates and, potentially, production of organic/inorganic composites. Four specific research thrusts are detailed in this document. First, chemical conversion of a nanostructured bioorganic template into a multicomponent oxide compound (tetragonal BaTiO3) via SSG coating and subsequent morphology-preserving microwave hydrothermal processing is demonstrated. Second, morphology-preserving chemical conversion of bioorganic templates into hierarchical photoluminescent microparticles is demonstrated to reveal both the dramatic change in properties such processing can provide, and the potential utility of chemically transformed templates in anti-counterfeiting / authentication applications. Third, determination of the reaction mechanism(s) for morphology-preserving microwave hydrothermal conversion of TiO2 to BaTiO3, through Au inert markers on single crystal rutile titania, is detailed. Finally, utilization of constructive coating techniques (SSG) and moderate temperature (< 500°C) heat treatments to modify and replicate structural color is coupled with deconstructive focused ion beam microsurgery to prepare samples for microscale structure interrogation. Specifically, the effects of coating thickness and composition on reflection spectra of structurally colored templates are examined. Also, the effects of the replacement of natural material with higher index of refraction inorganic materials on optical properties are discussed. The three processing research thrusts constituting chapters 1, 2 and 4 take advantage of moderate temperature processing to ensure nanocrystalline materials, either for shape preservation or to prevent scattering in optical applications. The research thrust detailed in chapter 3 examines hydrothermal conversion of TiO2 to BaTiO3, not only to identify the reaction mechanism(s) involved in hydrothermal conversion under morphology-preserving conditions, but also to introduce inert marker experiments to the field of microwave hydrothermal processing.

Conversion of Deletions during Recombination in Pneumococcal Transformation

PubMed Central

Lefevre, J. C.; Mostachfi, P.; Gasc, A. M.; Guillot, E.; Pasta, F.; Sicard, M.

1989-01-01

Genetic analysis of 16 deletions obtained in the amiA locus of pneumococcus is described. When present on donor DNA, all deletions increased drastically the frequency of wild-type recombinants in two-point crosses. This effect was maximal for deletions longer than 200 bases. It was reduced for heterologies shorter than 76 bases and did not exist for very short deletions. In three-point crosses in which the deletion was localized between two point mutations, we demonstrated that this excess of wild-type recombinants was the result of a genetic conversion. This conversion extended over several scores of bases outside the deletion. Conversion takes place during the heteroduplex stage of recombination. Therefore, in pneumococcal transformation, long heterologies participated in this heteroduplex configuration. As this conversion did not require an active DNA polymerase A gene it is proposed that the mechanism of conversion is not a DNA repair synthesis but involves breakage and ligation between DNA molecules. Conversion of deletions did not require the Hex system of correction of mismatched bases. It differs also from localized conversion. It appears that it is a process that evolved to correct errors of replication which lead to long heterologies and which are not eliminated by other systems. PMID:2599365

Process Design and Economics for the Conversion of Algal Biomass to Biofuels: Algal Biomass Fractionation to Lipid-and Carbohydrate-Derived Fuel Products

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

Davis, R.; Kinchin, C.; Markham, J.

2014-09-11

The U.S. Department of Energy (DOE) promotes the production of a range of liquid fuels and fuel blendstocks from biomass feedstocks by funding fundamental and applied research that advances the state of technology in biomass production, conversion, and sustainability. As part of its involvement in this program, the National Renewable Energy Laboratory (NREL) investigates the conceptual production economics of these fuels. This includes fuel pathways from lignocellulosic (terrestrial) biomass, as well as from algal (aquatic) biomass systems.

Formation of alcohol conversion catalysts

DOEpatents

Wachs, Israel E.; Cai, Yeping

2001-01-01

The method of the present invention involves a composition containing an intimate mixture of (a) metal oxide support particles and (b) a catalytically active metal oxide from Groups VA, VIA, or VIIA, its method of manufacture, and its method of use for converting alcohols to aldehydes. During the conversion process, catalytically active metal oxide from the discrete catalytic metal oxide particles migrates to the oxide support particles and forms a monolayer of catalytically active metal oxide on the oxide support particle to form a catalyst composition having a higher specific activity than the admixed particle composition.

Kinetic characteristics of polygalacturonase enzymes hydrolyzing galacturonic acid oligomers using isothermal titration calorimetry

USDA-ARS?s Scientific Manuscript database

Polygalacturonase enzymes hydrolyze the polygalacturonic acid chains found in pectin. Interest in polygalacturonase enzymes continues as they are useful in a number of industrial processes and conversely, detrimental, as they are involved in maceration of economically important crops. While a good...

Auger Up-Conversion of Low-Intensity Infrared Light in Engineered Quantum Dots

DOE PAGES

Makarov, Nikolay S.; Lin, Qianglu; Pietryga, Jeffrey M.; ...

2016-11-29

One source of efficiency losses in photovoltaic cells is their transparency toward solar photons with energies below the band gap of the absorbing layer. This loss can be reduced using a process of up-conversion whereby two or more sub-band-gap photons generate a single above-gap exciton. Traditional approaches to up-conversion, such as nonlinear two-photon absorption (2PA) or triplet fusion, suffer from low efficiency at solar light intensities, a narrow absorption bandwidth, nonoptimal absorption energies, and difficulties for implementing in practical devices. We show that these deficiencies can be alleviated using the effect of Auger up-conversion in thick-shell PbSe/CdSe quantum dots. Thismore » process relies on Auger recombination whereby two low-energy, core-based excitons are converted into a single higher-energy, shell-based exciton. When compared to their monocomponent counterparts, the tailored PbSe/CdSe heterostructures feature enhanced absorption cross-sections, a higher efficiency of the “productive” Auger pathway involving re-excitation of a hole, and longer lifetimes of both core- and shell-localized excitons. These features lead to effective up-conversion cross-sections that are more than 6 orders of magnitude higher than for standard nonlinear 2PA, which allows for efficient up-conversion of continuous wave infrared light at intensities as low as a few watts per square centimeter.« less

Carbothermic Synthesis of ~820- m UN Kernels. Investigation of Process Variables

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

Lindemer, Terrence; Silva, Chinthaka M; Henry, Jr, John James

2015-06-01

This report details the continued investigation of process variables involved in converting sol-gel-derived, urainia-carbon microspheres to ~820-μm-dia. UN fuel kernels in flow-through, vertical refractory-metal crucibles at temperatures up to 2123 K. Experiments included calcining of air-dried UO 3-H 2O-C microspheres in Ar and H 2-containing gases, conversion of the resulting UO 2-C kernels to dense UO 2:2UC in the same gases and vacuum, and its conversion in N 2 to in UC 1-xN x. The thermodynamics of the relevant reactions were applied extensively to interpret and control the process variables. Producing the precursor UO 2:2UC kernel of ~96% theoretical densitymore » was required, but its subsequent conversion to UC 1-xN x at 2123 K was not accompanied by sintering and resulted in ~83-86% of theoretical density. Decreasing the UC 1-xN x kernel carbide component via HCN evolution was shown to be quantitatively consistent with present and past experiments and the only useful application of H2 in the entire process.« less

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

Makarov, Nikolay S.; Lin, Qianglu; Pietryga, Jeffrey M.

One source of efficiency losses in photovoltaic cells is their transparency toward solar photons with energies below the band gap of the absorbing layer. This loss can be reduced using a process of up-conversion whereby two or more sub-band-gap photons generate a single above-gap exciton. Traditional approaches to up-conversion, such as nonlinear two-photon absorption (2PA) or triplet fusion, suffer from low efficiency at solar light intensities, a narrow absorption bandwidth, nonoptimal absorption energies, and difficulties for implementing in practical devices. We show that these deficiencies can be alleviated using the effect of Auger up-conversion in thick-shell PbSe/CdSe quantum dots. Thismore » process relies on Auger recombination whereby two low-energy, core-based excitons are converted into a single higher-energy, shell-based exciton. When compared to their monocomponent counterparts, the tailored PbSe/CdSe heterostructures feature enhanced absorption cross-sections, a higher efficiency of the “productive” Auger pathway involving re-excitation of a hole, and longer lifetimes of both core- and shell-localized excitons. These features lead to effective up-conversion cross-sections that are more than 6 orders of magnitude higher than for standard nonlinear 2PA, which allows for efficient up-conversion of continuous wave infrared light at intensities as low as a few watts per square centimeter.« less

Simulating the Conversion of Rural Settlements to Town Land Based on Multi-Agent Systems and Cellular Automata

PubMed Central

Liu, Yaolin; Kong, Xuesong; Liu, Yanfang; Chen, Yiyun

2013-01-01

Rapid urbanization in China has triggered the conversion of land from rural to urban use, particularly the conversion of rural settlements to town land. This conversion is the result of the joint effects of the geographic environment and agents involving the government, investors, and farmers. To understand the dynamic interaction dominated by agents and to predict the future landscape of town expansion, a small town land-planning model is proposed based on the integration of multi-agent systems (MAS) and cellular automata (CA). The MAS-CA model links the decision-making behaviors of agents with the neighbor effect of CA. The interaction rules are projected by analyzing the preference conflicts among agents. To better illustrate the effects of the geographic environment, neighborhood, and agent behavior, a comparative analysis between the CA and MAS-CA models in three different towns is presented, revealing interesting patterns in terms of quantity, spatial characteristics, and the coordinating process. The simulation of rural settlements conversion to town land through modeling agent decision and human-environment interaction is very useful for understanding the mechanisms of rural-urban land-use change in developing countries. This process can assist town planners in formulating appropriate development plans. PMID:24244472

Trends in biotechnological production of fuel ethanol from different feedstocks.

PubMed

Sánchez, Oscar J; Cardona, Carlos A

2008-09-01

Present work deals with the biotechnological production of fuel ethanol from different raw materials. The different technologies for producing fuel ethanol from sucrose-containing feedstocks (mainly sugar cane), starchy materials and lignocellulosic biomass are described along with the major research trends for improving them. The complexity of the biomass processing is recognized through the analysis of the different stages involved in the conversion of lignocellulosic complex into fermentable sugars. The features of fermentation processes for the three groups of studied feedstocks are discussed. Comparative indexes for the three major types of feedstocks for fuel ethanol production are presented. Finally, some concluding considerations on current research and future tendencies in the production of fuel ethanol regarding the pretreatment and biological conversion of the feedstocks are presented.

Normalizing Stigmatized Practices: Achieving Co-membership by "Doing Being Ordinary".

ERIC Educational Resources Information Center

Lawrence, Samuel G.

1996-01-01

Discusses the effect of the interactive accomplishment of conversational normalization. To illuminate this process, this article investigates how the parties to a news interview collaborate to normalize the interviewee's practices in operating a house of prostitution. The methodological impetus for this study involves a variant of conversation…

twzPEA: A Topology and Working Zone Based Pathway Enrichment Analysis Framework

USDA-ARS?s Scientific Manuscript database

Sensitive detection of involvement and adaptation of key signaling, regulatory, and metabolic pathways holds the key to deciphering molecular mechanisms such as those in the biomass-to-biofuel conversion process in yeast. Typical gene set enrichment analyses often do not use topology information in...

Efficient approach for bioethanol production from red seaweed Gelidium amansii.

PubMed

Kim, Ho Myeong; Wi, Seung Gon; Jung, Sera; Song, Younho; Bae, Hyeun-Jong

2015-01-01

Gelidium amansii (GA), a red seaweed species, is a popular source of food and chemicals due to its high galactose and glucose content. In this study, we investigated the potential of bioethanol production from autoclave-treated GA (ATGA). The proposed method involved autoclaving GA for 60min for hydrolysis to glucose. Separate hydrolysis and fermentation processing (SHF) achieved a maximum ethanol concentration of 3.33mg/mL, with a conversion yield of 74.7% after 6h (2% substrate loading, w/v). In contrast, simultaneous saccharification and fermentation (SSF) produced an ethanol concentration of 3.78mg/mL, with an ethanol conversion yield of 84.9% after 12h. We also recorded an ethanol concentration of 25.7mg/mL from SSF processing of 15% (w/v) dry matter from ATGA after 24h. These results indicate that autoclaving can improve the glucose and ethanol conversion yield of GA, and that SSF is superior to SHF for ethanol production. Copyright © 2014 Elsevier Ltd. All rights reserved.

Advantages and Uses of AMTEC

NASA Astrophysics Data System (ADS)

Lodhi, M. A. K.

2012-10-01

Static conversion systems are gaining importance in recent times because of newer applications of electricity like in spacecraft, hybrid-electric vehicles, military uses and domestic purposes. Of the many new static energy conversion systems that are being considered, one is the Alkali Metal Thermal Electric Converter (AMTEC). It is a thermally regenerative, electrochemical device for the direct conversion of heat to electrical power. As the name suggests, this system uses an alkali metal in its process. The electrochemical process involved in the working of AMTEC is ionization of alkali metal atoms at the interface of electrode and electrolyte. The electrons produced as a result flow through the external load thus doing work, and finally recombine with the metal ions at the cathode. AMTECs convert the work done during the nearly isothermal expansion of metal vapor to produce a high current and low voltage electron flow. Due to its principle of working it has many inherent advantages over other conventional generators. These will be discussed briefly.

The conversion of lignocellulosics to fermentable sugars: A survey of current research and application to CELSS

NASA Technical Reports Server (NTRS)

Petersen, Gene R.; Baresi, Larry

1990-01-01

An overview of the options for converting lignocellulosics into fermentable sugars as applied to the Closed Ecological Life Support System (CELSS) is given. A requirement for pretreatment is shown as well as the many available options. At present, physical/chemical methods are the simplest and best characterized options, but enzymatic processes will likely be the method of choice in the future. The use of pentose sugars by microorganisms to produce edibles at levels comparable to conventional plants is shown. The possible use of mycelial food production on pretreated but not hydrolyzed lignocelluloscis is also presented. Simple tradeoff analysis among some of the many possible biological pathways to regeneration of waste lignocellulosics was undertaken. Comparisons with complete oxidation processes were made. It is suggested that the NASA Life Sciences CELSS program maintain relationships with other government agencies involved in lignocellulosic conversions and use their expertise when the actual need for such conversion technology arises rather than develop this expertise within NASA.

Word Naming in the L1 and L2: A Dynamic Perspective on Automatization and the Degree of Semantic Involvement in Naming.

PubMed

Plat, Rika; Lowie, Wander; de Bot, Kees

2017-01-01

Reaction time data have long been collected in order to gain insight into the underlying mechanisms involved in language processing. Means analyses often attempt to break down what factors relate to what portion of the total reaction time. From a dynamic systems theory perspective or an interaction dominant view of language processing, it is impossible to isolate discrete factors contributing to language processing, since these continually and interactively play a role. Non-linear analyses offer the tools to investigate the underlying process of language use in time, without having to isolate discrete factors. Patterns of variability in reaction time data may disclose the relative contribution of automatic (grapheme-to-phoneme conversion) processing and attention-demanding (semantic) processing. The presence of a fractal structure in the variability of a reaction time series indicates automaticity in the mental structures contributing to a task. A decorrelated pattern of variability will indicate a higher degree of attention-demanding processing. A focus on variability patterns allows us to examine the relative contribution of automatic and attention-demanding processing when a speaker is using the mother tongue (L1) or a second language (L2). A word naming task conducted in the L1 (Dutch) and L2 (English) shows L1 word processing to rely more on automatic spelling-to-sound conversion than L2 word processing. A word naming task with a semantic categorization subtask showed more reliance on attention-demanding semantic processing when using the L2. A comparison to L1 English data shows this was not only due to the amount of language use or language dominance, but also to the difference in orthographic depth between Dutch and English. An important implication of this finding is that when the same task is used to test and compare different languages, one cannot straightforwardly assume the same cognitive sub processes are involved to an equal degree using the same task in different languages.

Risk assessment as standard work in design.

PubMed

Morrill, Patricia W

2013-01-01

This case study article examines a formal risk assessment as part of the decision making process for design solutions in high risk areas. The overview of the Failure Modes and Effects Analysis (FMEA) tool with examples of its application in hospital building projects will demonstrate the benefit of those structured conversations. This article illustrates how two hospitals used FMEA when integrating operational processes with building projects: (1) adjacency decision for Intensive Care Unit (ICU); and (2) distance concern for handling of specimens from Surgery to Lab. Both case studies involved interviews that exposed facility solution concerns. Just-in-time studies using the FMEA followed the same risk assessment process with the same workshop facilitator involving structured conversations in analyzing risks. In both cases, participants uncovered key areas of risk enabling them to take the necessary next steps. While the focus of this article is not the actual design solution, it is apparent that the risk assessment brought clarity to the situations resulting in prompt decision making about facility solutions. Hospitals are inherently risky environments; therefore, use of the formal risk assessment process, FMEA, is an opportunity for design professionals to apply more rigor to design decision making when facility solutions impact operations in high risk areas. Case study, decision making, hospital, infection control, strategy, work environment.

Modeling of helicon wave propagation and the physical process of helicon plasma production

NASA Astrophysics Data System (ADS)

Isayama, Shogo; Hada, Tohru; Shinohara, Shunjiro; Tanikawa, Takao

2014-10-01

Helicon plasma is a high-density and low-temperature plasma generated by the helicon wave, and is expected to be useful for various applications. On the other hand, there still remain a number of unsolved physical issues regarding how the plasma is generated using the helicon wave. The generation involves such physical processes as wave propagation, mode conversion, and collisionless as well as collisional wave damping that leads to ionization/recombination of neutral particles. In this study, we attempt to construct a model for the helicon plasma production using numerical simulations. In particular, we will make a quantitative argument on the roles of the mode conversion from the helicon to the electrostatic Trivelpiece-Gould (TG) wave, as first proposed by Shamrai. According to his scenario, the long wavelength helicon wave linearly mode converts to the TG wave, which then dissipates rapidly due to its large wave number. On the other hand, the efficiency of the mode conversion depends strongly on the magnitudes of dissipation parameters. Particularly when the dissipation is dominant, the TG wave is no longer excited and the input helicon wave directly dissipates. In the presentation, we will discuss the mode conversion and the plasma heating using numerical simulations.

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

Lebarbier Dagel, Vanessa M.; Li, J.; Taylor, Charles E.

This collaborative joint research project is in the area of advanced gasification and conversion, within the Chinese Academy of Sciences (CAS)-National Energy Technology Laboratory (NETL)-Pacific Northwest National Laboratory (PNNL) Memorandum of Understanding. The goal for this subtask is the development of advanced syngas conversion technologies. Two areas of investigation were evaluated: Sorption-Enhanced Synthetic Natural Gas Production from Syngas The conversion of synthetic gas (syngas) to synthetic natural gas (SNG) is typically catalyzed by nickel catalysts performed at moderate temperatures (275 to 325°C). The reaction is highly exothermic and substantial heat is liberated, which can lead to process thermal imbalance andmore » destruction of the catalyst. As a result, conversion per pass is typically limited, and substantial syngas recycle is employed. Commercial methanation catalysts and processes have been developed by Haldor Topsoe, and in some reports, they have indicated that there is a need and opportunity for thermally more robust methanation catalysts to allow for higher per-pass conversion in methanation units. SNG process requires the syngas feed with a higher H2/CO ratio than typically produced from gasification processes. Therefore, the water-gas shift reaction (WGS) will be required to tailor the H2/CO ratio. Integration with CO2 separation could potentially eliminate the need for a separate WGS unit, thereby integrating WGS, methanation, and CO2 capture into one single unit operation and, consequently, leading to improved process efficiency. The SNG process also has the benefit of producing a product stream with high CO2 concentrations, which makes CO2 separation more readily achievable. The use of either adsorbents or membranes that selectively separate the CO2 from the H2 and CO would shift the methanation reaction (by driving WGS for hydrogen production) and greatly improve the overall efficiency and economics of the process. The scope of this activity was to develop methods and enabling materials for syngas conversion to SNG with readily CO2 separation. Suitable methanation catalyst and CO2 sorbent materials were developed. Successful proof-of-concept for the combined reaction-sorption process was demonstrated, which culminated in a research publication. With successful demonstration, a decision was made to switch focus to an area of fuels research of more interest to all three research institutions (CAS-NETL-PNNL). Syngas-to-Hydrocarbon Fuels through Higher Alcohol Intermediates There are two types of processes in syngas conversion to fuels that are attracting R&D interest: 1) syngas conversion to mixed alcohols; and 2) syngas conversion to gasoline via the methanol-to-gasoline process developed by Exxon-Mobil in the 1970s. The focus of this task was to develop a one-step conversion technology by effectively incorporating both processes, which is expected to reduce the capital and operational cost associated with the conversion of coal-derived syngas to liquid fuels. It should be noted that this work did not further study the classic Fischer-Tropsch reaction pathway. Rather, we focused on the studies for unique catalyst pathways that involve the direct liquid fuel synthesis enabled by oxygenated intermediates. Recent advances made in the area of higher alcohol synthesis including the novel catalytic composite materials recently developed by CAS using base metal catalysts were used.« less

Reported Speech in Conversational Storytelling during Nursing Shift Handover Meetings

ERIC Educational Resources Information Center

Bangerter, Adrian; Mayor, Eric; Pekarek Doehler, Simona

2011-01-01

Shift handovers in nursing units involve formal transmission of information and informal conversation about non-routine events. Informal conversation often involves telling stories. Direct reported speech (DRS) was studied in handover storytelling in two nursing care units. The study goal is to contribute to a better understanding of conversation…

Techniques for animation of CFD results. [computational fluid dynamics

NASA Technical Reports Server (NTRS)

Horowitz, Jay; Hanson, Jeffery C.

1992-01-01

Video animation is becoming increasingly vital to the computational fluid dynamics researcher, not just for presentation, but for recording and comparing dynamic visualizations that are beyond the current capabilities of even the most powerful graphic workstation. To meet these needs, Lewis Research Center has recently established a facility to provide users with easy access to advanced video animation capabilities. However, producing animation that is both visually effective and scientifically accurate involves various technological and aesthetic considerations that must be understood both by the researcher and those supporting the visualization process. These considerations include: scan conversion, color conversion, and spatial ambiguities.

End-of-life care communications and shared decision-making in Norwegian nursing homes--experiences and perspectives of patients and relatives.

PubMed

Gjerberg, Elisabeth; Lillemoen, Lillian; Førde, Reidun; Pedersen, Reidar

2015-08-19

Involving nursing home patients and their relatives in end-of-life care conversations and treatment decisions has recently gained increased importance in several Western countries. However, there is little knowledge about how the patients themselves and their next-of-kin look upon involvement in end-of-life care decisions. The purpose of this paper is to explore nursing home patients' and next-of-kin's experiences with- and perspectives on end-of-life care conversations, information and shared decision-making. The study has a qualitative and explorative design, based on a combination of individual interviews with 35 patients living in six nursing homes and seven focus group interviews with 33 relatives. The data was analysed applying a "bricolage" approach". Participation was based on informed consent, and the study was approved by the Regional Committees for Medical and Health Research Ethics. Few patients and relatives had participated in conversations about end-of-life care. Most relatives wanted such conversations, while the patients' opinions varied. With some exceptions, patients and relatives wanted to be informed about the patient's health condition. The majority wanted to be involved in the decision-making process, but leave the final decisions to the health professionals. Among the patients, the opinion varied; some patients wanted to leave the decisions more or less completely to the nursing home staff. Conversations about end-of-life care issues are emotionally challenging, and very few patients had discussed these questions with their family. The relatives' opinions of the patient's preferences were mainly based on assumptions; they had seldom talked about this explicitly. Both patients and relatives wanted the staff to raise these questions. Nursing home staff should initiate conversations about preferences for end-of-life care, assisting patients and relatives in talking about these issues, while at the same time being sensitive to the diversity in opinions and the timing for such conversations. As the popularity of advance care planning increases in many Western countries, discussions of patients' and relatives' perspectives will be of great interest to a broader audience.

Emphasizing the only character: emphasis, attention and contrast.

PubMed

Chen, Lijing; Yang, Yufang

2015-03-01

In conversations, pragmatic information such as emphasis is important for identifying the speaker's/writer's intention. The present research examines the cognitive processes involved in emphasis processing. Participants read short discourses that introduced one or two character(s), with the character being emphasized or non-emphasized in subsequent texts. Eye movements showed that: (1) early processing of the emphasized word was facilitated, which may have been due to increased attention allocation, whereas (2) late integration of the emphasized character was inhibited when the discourse involved only this character. These results indicate that it is necessary to include other characters as contrastive characters to facilitate the integration of an emphasized character, and support the existence of a relationship between Emphasis and Contrast computation. Taken together, our findings indicate that both attention allocation and contrast computation are involved in emphasis processing, and support the incremental nature of sentence processing and the importance of contrast in discourse comprehension. Copyright © 2014 Elsevier B.V. All rights reserved.

Framing the Issue: Religion, Secular Ethics and the Case of Animal Rights Mobilization

ERIC Educational Resources Information Center

Mika, Marie

2006-01-01

This article addresses social movement framing, generally, and within contemporary animal rights movements specifically by conducting focus group analyses of a non-activist population. This contrasts with previous studies of recruitment that have examined the conversion process retroactively, culling data from those already involved in a cause. By…

Taking It to the Classroom: Strategies for Re-Claiming Citizenship through Communication Education.

ERIC Educational Resources Information Center

Kelley, Colleen E.

Speech communication in general and rhetoric in particular address suggestions for protecting the "space" in which public conversation occurs in a democracy. Although the framers of the Constitution clearly envisioned significant citizen involvement in policy making, citizen access to the process has greatly declined, especially at the…

Mutation of Photosystem II D1 protein that empower efficient phenotypes of Chlamydomonas Reinhardtii under extreme environment in space

USDA-ARS?s Scientific Manuscript database

Oxygenic photosynthesis involves capture and conversion of light energy into chemical energy, a process fundamental to life including plant productivity on Earth. Photosynthetic electron transport is catalyzed by two photochemical reaction centres in series, photosystem II (PS II) and photosytem I (...

Undergraduate Student Perspectives on Electronic Portfolio Assessment in College Composition Courses

ERIC Educational Resources Information Center

Fullerton, Bridget Katherine Jean

2017-01-01

Though Linda Adler-Kassner and Peggy O'Neill claim that ethical writing assessment models "must be designed and built collaboratively, with careful attention to the values and passions of all involved, through a process that provides access to all," college students have not typically been included in scholarly conversations about…

Collaboration, Multi-Tasking and Problem Solving Performance in Shared Virtual Spaces

ERIC Educational Resources Information Center

Lin, Lin; Mills, Leila A.; Ifenthaler, Dirk

2016-01-01

Collaborative problem-solving is often not a sequential process; instead, it can involve tasking switching or dual tasking (i.e., multitasking) activities in that the collaborators need to shift their attention between the targeted problems and the conversations they carry on with their collaborators. It is not known to what extent the…

Using Active Learning in a Studio Classroom to Teach Molecular Biology

ERIC Educational Resources Information Center

Nogaj, Luiza A.

2013-01-01

This article describes the conversion of a lecture-based molecular biology course into an active learning environment in a studio classroom. Specific assignments and activities are provided as examples. The goal of these activities is to involve students in collaborative learning, teach them how to participate in the learning process, and give…

Current challenges in organic photovoltaic solar energy conversion.

PubMed

Schlenker, Cody W; Thompson, Mark E

2012-01-01

Over the last 10 years, significant interest in utilizing conjugated organic molecules for solid-state solar to electric conversion has produced rapid improvement in device efficiencies. Organic photovoltaic (OPV) devices are attractive for their compatibility with low-cost processing techniques and thin-film applicability to flexible and conformal applications. However, many of the processes that lead to power losses in these systems still remain poorly understood, posing a significant challenge for the future efficiency improvements required to make these devices an attractive solar technology. While semiconductor band models have been employed to describe OPV operation, a more appropriate molecular picture of the pertinent processes is beginning to emerge. This chapter presents mechanisms of OPV device operation, based on the bound molecular nature of the involved transient species. With the intention to underscore the importance of considering both thermodynamic and kinetic factors, recent progress in elucidating molecular characteristics that dictate photovoltage losses in heterojunction organic photovoltaics is also discussed.

Geographic Differences in Time to Culture Conversion in Liquid Media: Tuberculosis Trials Consortium Study 28. Culture Conversion Is Delayed in Africa

PubMed Central

Mac Kenzie, William R.; Heilig, Charles M.; Bozeman, Lorna; Johnson, John L.; Muzanye, Grace; Dunbar, Denise; Jost, Kenneth C.; Diem, Lois; Metchock, Beverly; Eisenach, Kathleen; Dorman, Susan; Goldberg, Stefan

2011-01-01

Background Tuberculosis Trials Consortium Study 28, was a double blind, randomized, placebo-controlled, phase 2 clinical trial examining smear positive pulmonary Mycobacterium tuberculosis. Over the course of intensive phase therapy, patients from African sites had substantially delayed and lower rates of culture conversion to negative in liquid media compared to non-African patients. We explored potential explanations of this finding. Methods In TBTC Study 28, protocol-correct patients (n = 328) provided spot sputum specimens for M. tuberculosis culture in liquid media, at baseline and weeks 2, 4, 6 and 8 of study therapy. We compared sputum culture conversion for African and non-African patients stratified by four baseline measures of disease severity: AFB smear quantification, extent of disease on chest radiograph, cavity size and the number of days to detection of M. tuberculosis in liquid media using the Kaplan-Meier product-limit method. We evaluated specimen processing and culture procedures used at 29 study laboratories serving 27 sites. Results African TB patients had more extensive disease at enrollment than non-African patients. However, African patients with the least disease by the 4 measures of disease severity had conversion rates on liquid media that were substantially lower than conversion rates in non-African patients with the greatest extent of disease. HIV infection, smoking and diabetes did not explain delayed conversion in Africa. Some inter-site variation in laboratory processing and culture procedures within accepted practice for clinical diagnostic laboratories was found. Conclusions Compared with patients from non-African sites, African patients being treated for TB had delayed sputum culture conversion and lower sputum conversion rates in liquid media that were not explained by baseline severity of disease, HIV status, age, smoking, diabetes or race. Further investigation is warranted into whether modest variation in laboratory processes substantially influences the efficacy outcomes of phase 2 TB treatment trials or if other factors (e.g., nutrition, host response) are involved. Trial Registration ClinicalTrials.gov NCT00144417 PMID:21494548

Separation of Corn Fiber and Conversion to Fuels and Chemicals Phase II: Pilot-scale Operation

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

Abbas, Charles; Beery, Kyle; Orth, Rick

2007-09-28

The purpose of the Department of Energy (DOE)-supported corn fiber conversion project, “Separation of Corn Fiber and Conversion to Fuels and Chemicals Phase II: Pilot-scale Operation” is to develop and demonstrate an integrated, economical process for the separation of corn fiber into its principal components to produce higher value-added fuel (ethanol and biodiesel), nutraceuticals (phytosterols), chemicals (polyols), and animal feed (corn fiber molasses). This project has successfully demonstrated the corn fiber conversion process on the pilot scale, and ensured that the process will integrate well into existing ADM corn wet-mills. This process involves hydrolyzing the corn fiber to solubilize 50%more » of the corn fiber as oligosaccharides and soluble protein. The solubilized fiber is removed and the remaining fiber residue is solvent extracted to remove the corn fiber oil, which contains valuable phytosterols. The extracted oil is refined to separate the phytosterols and the remaining oil is converted to biodiesel. The de-oiled fiber is enzymatically hydrolyzed and remixed with the soluble oligosaccharides in a fermentation vessel where it is fermented by a recombinant yeast, which is capable of fermenting the glucose and xylose to produce ethanol. The fermentation broth is distilled to remove the ethanol. The stillage is centrifuged to separate the yeast cell mass from the soluble components. The yeast cell mass is sold as a high-protein yeast cream and the remaining sugars in the stillage can be purified to produce a feedstock for catalytic conversion of the sugars to polyols (mainly ethylene glycol and propylene glycol) if desirable. The remaining materials from the purification step and any materials remaining after catalytic conversion are concentrated and sold as a corn fiber molasses. Additional high-value products are being investigated for the use of the corn fiber as a dietary fiber sources.« less

Biological valorization of low molecular weight lignin.

PubMed

Abdelaziz, Omar Y; Brink, Daniel P; Prothmann, Jens; Ravi, Krithika; Sun, Mingzhe; García-Hidalgo, Javier; Sandahl, Margareta; Hulteberg, Christian P; Turner, Charlotta; Lidén, Gunnar; Gorwa-Grauslund, Marie F

2016-12-01

Lignin is a major component of lignocellulosic biomass and as such, it is processed in enormous amounts in the pulp and paper industry worldwide. In such industry it mainly serves the purpose of a fuel to provide process steam and electricity, and to a minor extent to provide low grade heat for external purposes. Also from other biorefinery concepts, including 2nd generation ethanol, increasing amounts of lignin will be generated. Other uses for lignin - apart from fuel production - are of increasing interest not least in these new biorefinery concepts. These new uses can broadly be divided into application of the polymer as such, native or modified, or the use of lignin as a feedstock for the production of chemicals. The present review focuses on the latter and in particular the advances in the biological routes for chemicals production from lignin. Such a biological route will likely involve an initial depolymerization, which is followed by biological conversion of the obtained smaller lignin fragments. The conversion can be either a short catalytic conversion into desired chemicals, or a longer metabolic conversion. In this review, we give a brief summary of sources of lignin, methods of depolymerization, biological pathways for conversion of the lignin monomers and the analytical tools necessary for characterizing and evaluating key lignin attributes. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Quantification of process variables for carbothermic synthesis of UC 1-xN x fuel microspheres

DOE PAGES

Lindemer, Terrance B.; Silva, Chinthaka M.; Henry, Jr, John James; ...

2016-11-05

This report details the continued investigation of process variables involved in converting sol-gel-derived, urania-carbon microspheres to ~820-μm-dia. UC 1-xN x fuel kernels in flow-through, vertical Mo and W crucibles at temperatures up to 2123 K. Experiments included calcining of air-dried UO 3-H 2O-C microspheres in Ar and H 2-containing gases, conversion of the resulting UO 2-C kernels to dense UO2:2UC in the same gases and vacuum, and its conversion in N 2 to UC 1-xN x (x = ~0.85). The thermodynamics of the relevant reactions were applied extensively to interpret and control the process variables. Producing the precursor UO 2:2UCmore » kernel of ~96% theoretical density was required, but its subsequent conversion to UC 1-xN x at 2123 K was not accompanied by sintering and resulted in ~83-86% of theoretical density. Increasing the UC 1-xN x kernel nitride component to ~0.98 in flowing N 2-H 2 mixtures to evolve HCN was shown to be quantitatively consistent with present and past experiments and the only useful application of H 2 in the entire process.« less

Quantification of process variables for carbothermic synthesis of UC1-xNx fuel microspheres

NASA Astrophysics Data System (ADS)

Lindemer, T. B.; Silva, C. M.; Henry, J. J.; McMurray, J. W.; Voit, S. L.; Collins, J. L.; Hunt, R. D.

2017-01-01

This report details the continued investigation of process variables involved in converting sol-gel-derived, urania-carbon microspheres to ∼820-μm-dia. UC1-xNx fuel kernels in flow-through, vertical Mo and W crucibles at temperatures up to 2123 K. Experiments included calcining of air-dried UO3-H2O-C microspheres in Ar and H2-containing gases, conversion of the resulting UO2-C kernels to dense UO2:2UC in the same gases and vacuum, and its conversion in N2 to UC1-xNx (x = ∼0.85). The thermodynamics of the relevant reactions were applied extensively to interpret and control the process variables. Producing the precursor UO2:2UC kernel of ∼96% theoretical density was required, but its subsequent conversion to UC1-xNx at 2123 K was not accompanied by sintering and resulted in ∼83-86% of theoretical density. Increasing the UC1-xNx kernel nitride component to ∼0.98 in flowing N2-H2 mixtures to evolve HCN was shown to be quantitatively consistent with present and past experiments and the only useful application of H2 in the entire process.

Prosopagnosia as a Type of Conversion Disorder.

PubMed

Power, Clodagh; Hannigan, Oisin; Coen, Robert; Bruce, Irene; Gibb, Matthew; McCarthy, Marie; Robinson, David; Lawlor, Brian A

2018-01-01

Conversion disorder is a common and debilitating condition that remains poorly understood. We present a previously undescribed form of conversion disorder to highlight the complexity of the condition and consider the interplay of factors that produce conversion symptoms. A 50-year-old male presented with acquired prosopagnosia and language impairment. Neuropsychological testing indicated right temporal lobe dysfunction. Extensive work-up outruled an organic aetiology. Reactivation of childhood trauma coincided with the onset of his symptoms. Childhood trauma is known to have adverse effects on the developing brain which may affect an individual's emotional behaviour and coping style. Functional neuroimaging techniques suggest that conversion symptoms may be linked to the disruption of higher order neural circuitry involved in the integration of emotional processing and cortical functioning. We propose that our patient's adverse childhood experiences led to the development of a particular personality and coping style that "primed" him for a later abnormal emotional and behavioural response when confronted with reminders of his traumatic background. Further interdisciplinary studies are required to further elucidate the neurobiological basis for this condition.

Translational errors as an early event in prion conversion.

PubMed

Hatin, I; Bidou, L; Cullin, C; Rousset, J P

2001-01-01

A prion is an infectious, altered form of a cellular protein which can self-propagate and affect normal phenotype. Prion conversion has been observed for mammalian and yeast proteins but molecular mechanisms that trigger this process remain unclear. Up to now, only post-translational models have been explored. In this work, we tested the hypothesis that co-translational events may be implicated in the conformation changes of the Ure2p protein of Saccharomyces cerevisiae. This protein can adopt a prion conformation leading to an [URE3] phenotype which can be easily assessed and quantified. We analyzed the effect of two antibiotics, known to affect translation, on [URE3] conversion frequency. For cells treated with G418 we observed a parallel increase of translational errors rate and frequency of [URE3] conversion. By contrast, cycloheximide which was not found to affect translational fidelity, has no influence on the induction of [URE3] phenotype. These results raise the possibility that the mechanism of prion conversion might not only involve alternative structures of strictly identical molecules but also aberrant proteins resulting from translational errors.

Indole-3-butyric acid promotes adventitious rooting in Arabidopsis thaliana thin cell layers by conversion into indole-3-acetic acid and stimulation of anthranilate synthase activity.

PubMed

Fattorini, L; Veloccia, A; Della Rovere, F; D'Angeli, S; Falasca, G; Altamura, M M

2017-07-11

Indole-3-acetic acid (IAA), and its precursor indole-3-butyric acid (IBA), control adventitious root (AR) formation in planta. Adventitious roots are also crucial for propagation via cuttings. However, IBA role(s) is/are still far to be elucidated. In Arabidopsis thaliana stem cuttings, 10 μM IBA is more AR-inductive than 10 μM IAA, and, in thin cell layers (TCLs), IBA induces ARs when combined with 0.1 μM kinetin (Kin). It is unknown whether arabidopsis TCLs produce ARs under IBA alone (10 μM) or IAA alone (10 μM), and whether they contain endogenous IAA/IBA at culture onset, possibly interfering with the exogenous IBA/IAA input. Moreover, it is unknown whether an IBA-to-IAA conversion is active in TCLs, and positively affects AR formation, possibly through the activity of the nitric oxide (NO) deriving from the conversion process. Revealed undetectable levels of both auxins at culture onset, showing that arabidopsis TCLs were optimal for investigating AR-formation under the total control of exogenous auxins. The AR-response of TCLs from various ecotypes, transgenic lines and knockout mutants was analyzed under different treatments. It was shown that ARs are better induced by IBA than IAA and IBA + Kin. IBA induced IAA-efflux (PIN1) and IAA-influx (AUX1/LAX3) genes, IAA-influx carriers activities, and expression of ANTHRANILATE SYNTHASE -alpha1 (ASA1), a gene involved in IAA-biosynthesis. ASA1 and ANTHRANILATE SYNTHASE -beta1 (ASB1), the other subunit of the same enzyme, positively affected AR-formation in the presence of exogenous IBA, because the AR-response in the TCLs of their mutant wei2wei7 was highly reduced. The AR-response of IBA-treated TCLs from ech2ibr10 mutant, blocked into IBA-to-IAA-conversion, was also strongly reduced. Nitric oxide, an IAA downstream signal and a by-product of IBA-to-IAA conversion, was early detected in IAA- and IBA-treated TCLs, but at higher levels in the latter explants. Altogether, results showed that IBA induced AR-formation by conversion into IAA involving NO activity, and by a positive action on IAA-transport and ASA1/ASB1-mediated IAA-biosynthesis. Results are important for applications aimed to overcome rooting recalcitrance in species of economic value, but mainly for helping to understand IBA involvement in the natural process of adventitious rooting.

Rate Kinetics and Molecular Dynamics of the Structural Transitions in Amyloidogenic Proteins

NASA Astrophysics Data System (ADS)

Steckmann, Timothy M.

Amyloid fibril aggregation is associated with several horrific diseases such as Alzheimer's, Creutzfeld-Jacob, diabetes, Parkinson's and others. The process of amyloid aggregation involves forming myriad different metastable intermediate aggregates. Amyloid fibrils are composed of proteins that originate in an innocuous alpha-helix or random-coil structure. The alpha-helices convert their structure to beta-strands that aggregate into beta-sheets, and then into protofibrils, and ultimately into fully formed amyloid fibrils. On the basis of experimental data, I have developed a mathematical model for the kinetics of the reaction pathways and determined rate parameters for peptide secondary structural conversion and aggregation during the entire fibrillogenesis process from random coil to fibrils, including the molecular species that accelerate the conversions. The specific steps of the model and the rate constants that are determined by fitting to experimental data provide insight on the molecular species involved in the fibril formation process. To better understand the molecular basis of the protein structural transitions and aggregation, I report on molecular dynamics (MD) computational studies on the formation of amyloid protofibrillar structures in the small model protein ccbeta, which undergoes many of the structural transitions of the larger, naturally occurring amyloid forming proteins. Two different structural transition processes involving hydrogen bonds are observed for aggregation into fibrils: the breaking of intrachain hydrogen bonds to allow beta-hairpin proteins to straighten, and the subsequent formation of interchain hydrogen bonds during aggregation into amyloid fibrils. For my MD simulations, I found that the temperature dependence of these two different structural transition processes results in the existence of a temperature window that the ccbeta protein experiences during the process of forming protofibrillar structures. Both the mathematical modeling of the kinetics and the MD simulations show that molecular structural heterogeneity is a major factor in the process. The MD simulations also show that intrachain and interchain hydrogen bonds breaking and forming is strongly correlated to the process of amyloid formation.

"It's Like Having a Metal Detector at the Door": A Conversation with Students about Voice.

ERIC Educational Resources Information Center

Garcia, Florencia; And Others

1995-01-01

Presents a dialogue among three student coresearchers who participated in a longitudinal research project about their motivation to learn. The dialogue highlights what it meant to them to have a voice, what was involved in having a voice, how to improve the process, and how they felt about being coresearchers. (SM)

Survival of Escherichia coli under lethal heat stress by L-form conversion.

PubMed

Markova, Nadya; Slavchev, Georgi; Michailova, Lilia; Jourdanova, Mimi

2010-06-09

Transition of bacteria to cell wall deficient L-forms in response to stress factors has been assumed as a potential mechanism for survival of microbes under unfavorable conditions. In this article, we provide evidence of paradoxal survival through L-form conversion of E. coli high cell density population after lethal treatments (boiling or autoclaving). Light and transmission electron microscopy demonstrated conversion from classical rod to polymorphic L-form shape morphology and atypical growths of E. coli. Microcrystal formations observed at this stage were interpreted as being closely linked to the processes of L-form conversion and probably involved in the general phenomenon of protection against lethal environment. Identity of the morphologically modified L-forms as E. coli was verified by species specific DNA-based test. Our study might contribute to a better understanding of the L-form phenomenon and its importance for bacterial survival, as well as provoke reexamination of the traditional view of killing strategies against bacteria.

Survival of Escherichia coli under lethal heat stress by L-form conversion

PubMed Central

Markova, Nadya; Slavchev, Georgi; Michailova, Lilia; Jourdanova, Mimi

2010-01-01

Transition of bacteria to cell wall deficient L-forms in response to stress factors has been assumed as a potential mechanism for survival of microbes under unfavorable conditions. In this article, we provide evidence of paradoxal survival through L-form conversion of E. coli high cell density population after lethal treatments (boiling or autoclaving). Light and transmission electron microscopy demonstrated conversion from classical rod to polymorphic L-form shape morphology and atypical growths of E. coli. Microcrystal formations observed at this stage were interpreted as being closely linked to the processes of L-form conversion and probably involved in the general phenomenon of protection against lethal environment. Identity of the morphologically modified L-forms as E. coli was verified by species specific DNA-based test. Our study might contribute to a better understanding of the L-form phenomenon and its importance for bacterial survival, as well as provoke reexamination of the traditional view of killing strategies against bacteria. PMID:20582223

Luminescence of Er 3+-doped nanostructured SiO 2-LaF 3 glass-ceramics prepared by the sol-gel method

NASA Astrophysics Data System (ADS)

Rodríguez, V. D.; Del Castillo, J.; Yanes, A. C.; Méndez-Ramos, J.; Torres, M.; Peraza, J.

2007-07-01

Transparent glass ceramics with composition of 95SiO2-5LaF3 doped with 0.1 mol% of Er3+ were synthesized by thermal treatment of precursor sol-gel glasses. Segregated LaF3 nanocrystals in the glass were confirmed from a structural analysis performed by X-ray diffraction. Blue, green and red efficient up-conversion emissions were observed under 980 nm excitation at room temperature. Under this excitation near infrared down-conversion at 1.55 μm is also observed. These results could be attributed to the precipitation of LaF3 nanocrystals and the incorporation of most Er3+ ions in these nanocrystals. The mechanisms involved in the up-conversion emissions could be ascribed to two and three photon processes.

Critical technology limits to silicon material and sheet production

NASA Technical Reports Server (NTRS)

Leipold, M. H.

1982-01-01

Earlier studies have indicated that expenditures related to the preparation of high-purity silicon and its conversion to silicon sheet represent from 40 to 52 percent of the cost of the entire panel. The present investigation is concerned with the elements which were selected for study in connection with the Flat-Plate Solar Array (FSA) Project. The first of two technologies which are being developed within the FSA Project involves the conversion of metallurgical-grade silicon through a silane purification process to silicon particles. The second is concerned with the conversion of trichlorosilane to dichlorosilane, and the subsequent production of silicon using modified rod reactors of the Siemens type. With respect to silicon sheet preparation, efforts have been focused both on the preparation of ingots, followed by wafering, and the direct crystallization of molten silicon into a ribbon or film.

Conversion from Tree to Graph Representation of Requirements

NASA Technical Reports Server (NTRS)

Mayank, Vimal; Everett, David Frank; Shmunis, Natalya; Austin, Mark

2009-01-01

A procedure and software to implement the procedure have been devised to enable conversion from a tree representation to a graph representation of the requirements governing the development and design of an engineering system. The need for this procedure and software and for other requirements-management tools arises as follows: In systems-engineering circles, it is well known that requirements- management capability improves the likelihood of success in the team-based development of complex systems involving multiple technological disciplines. It is especially desirable to be able to visualize (in order to identify and manage) requirements early in the system- design process, when errors can be corrected most easily and inexpensively.

The "big bang" implementation: not for the faint of heart.

PubMed

Anderson, Linda K; Stafford, Cynthia J

2002-01-01

Replacing a hospital's obsolete mainframe computer system with a modern integrated clinical and administrative information system presents multiple challenges. When the new system is activated in one weekend, in "big bang" fashion, the challenges are magnified. Careful planning is essential to ensure that all hospital staff are fully prepared for this transition, knowing this conversion will involve system downtime, procedural changes, and the resulting stress that naturally accompanies change. Implementation concerns include staff preparation and training, process changes, continuity of patient care, and technical and administrative support. This article outlines how the University of Missouri Health Care addressed these operational concerns during this dramatic information system conversion.

Public Involvement Opportunities for the DUF6 Conversion Facility EISs

Science.gov Websites

and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home » Conversion Management | DUF6 Conversion Facility EISs | Documents News | FAQs | Internet Resources | Glossary Help

Two-dimensional correlation and codistribution spectroscopy (2DCOS and 2DCDS) analyses of time-dependent ATR IR spectra of D-glucose anomers undergoing mutarotation process in water

NASA Astrophysics Data System (ADS)

Noda, Isao

2018-05-01

Two cyclic diastereoisomeric structures, known as α- and β-anomers of D-glucose with different configurations around C1 with OH groups in axial or equitroial positions, undergo the mutarotation conversion to each other in water. Two-dimensional correlation and codistribution spectroscopy (2DCOS and 2DCDS) analyses were applied to the time-dependent ATR IR spectra of aqueous solutions of α- and β-D-glucose undergoing such mutarotation conversion. 2DCOS analysis reveals that the increase and decrease in the IR intensities after the dissolution of α- or β-D-glucose are not fully synchronized, suggesting the mutarotation of D-glucose in water is not a simple binary conversion process but a multi-step reaction involving an intermediate species with a finite and observable concentration level and lifetime. 2DCDS analysis of the time-dependent ATR IR spectra clearly demonstrated the presence of intermediate species contributing to the band positions overlapped close to bands for α- and β-D-glucose. The fact that band positions identified for the intermediate species for α- to β-D-glucose conversion are the same for the reverse reaction suggests that they arise from the same species, most likely the open-ring structure produced by the hydrolysis.

Data management in pattern recognition and image processing systems

NASA Technical Reports Server (NTRS)

Zobrist, A. L.; Bryant, N. A.

1976-01-01

Data management considerations are important to any system which handles large volumes of data or where the manipulation of data is technically sophisticated. A particular problem is the introduction of image-formatted files into the mainstream of data processing application. This report describes a comprehensive system for the manipulation of image, tabular, and graphical data sets which involve conversions between the various data types. A key characteristic is the use of image processing technology to accomplish data management tasks. Because of this, the term 'image-based information system' has been adopted.

Development of digital sideband separating down-conversion for Yuan-Tseh Lee Array

NASA Astrophysics Data System (ADS)

Li, Chao-Te; Kubo, Derek; Cheng, Jen-Chieh; Kuroda, John; Srinivasan, Ranjani; Ho, Solomon; Guzzino, Kim; Chen, Ming-Tang

2016-07-01

This report presents a down-conversion method involving digital sideband separation for the Yuan-Tseh Lee Array (YTLA) to double the processing bandwidth. The receiver consists of a MMIC HEMT LNA front end operating at a wavelength of 3 mm, and sub-harmonic mixers that output signals at intermediate frequencies (IFs) of 2-18 GHz. The sideband separation scheme involves an analog 90° hybrid followed by two mixers that provide down-conversion of the IF signal to a pair of in-phase (I) and quadrature (Q) signals in baseband. The I and Q baseband signals are digitized using 5 Giga sample per second (Gsps) analog-to-digital converters (ADCs). A second hybrid is digitally implemented using field-programmable gate arrays (FPGAs) to produce two sidebands, each with a bandwidth of 1.6 GHz. The 2 x 1.6 GHz band can be tuned to cover any 3.6 GHz window within the aforementioned IF range of the array. Sideband rejection ratios (SRRs) above 20 dB can be obtained across the 3.6 GHz bandwidth by equalizing the power and delay between the I and Q baseband signals. Furthermore, SRRs above 30 dB can be achieved when calibration is applied.

Strategic planning--a plan for excellence for South Haven Health System.

PubMed

Urbanski, Joanne; Baskel, Maureen; Martelli, Mary

2011-01-01

South Haven Health System has developed an innovative approach to strategic planning. The key to success of this process has been the multidisciplinary involvement of all stakeholders from the first planning session through the final formation of a strategic plan with measurable objectives for each goal. The process utilizes a Conversation Café method for identifying opportunities and establishing goals, Strategic Oversight Teams to address each goal and a Champion for implementation of each objective. Progress is measured quarterly by Strategic Oversight Team report cards. Transparency of communication within the organization and the sharing of information move the plan forward. The feedback from participant evaluations has been overwhelmingly positive. They are involved and excited.

Public Involvement Opportunities for the DUF6 Conversion Facility EISs

Science.gov Websites

and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home » Conversion | DU Uses | DUF6 Management | DUF6 Conversion Facility EISs | Documents News | FAQs | Internet

Word Naming in the L1 and L2: A Dynamic Perspective on Automatization and the Degree of Semantic Involvement in Naming

PubMed Central

Plat, Rika; Lowie, Wander; de Bot, Kees

2018-01-01

Reaction time data have long been collected in order to gain insight into the underlying mechanisms involved in language processing. Means analyses often attempt to break down what factors relate to what portion of the total reaction time. From a dynamic systems theory perspective or an interaction dominant view of language processing, it is impossible to isolate discrete factors contributing to language processing, since these continually and interactively play a role. Non-linear analyses offer the tools to investigate the underlying process of language use in time, without having to isolate discrete factors. Patterns of variability in reaction time data may disclose the relative contribution of automatic (grapheme-to-phoneme conversion) processing and attention-demanding (semantic) processing. The presence of a fractal structure in the variability of a reaction time series indicates automaticity in the mental structures contributing to a task. A decorrelated pattern of variability will indicate a higher degree of attention-demanding processing. A focus on variability patterns allows us to examine the relative contribution of automatic and attention-demanding processing when a speaker is using the mother tongue (L1) or a second language (L2). A word naming task conducted in the L1 (Dutch) and L2 (English) shows L1 word processing to rely more on automatic spelling-to-sound conversion than L2 word processing. A word naming task with a semantic categorization subtask showed more reliance on attention-demanding semantic processing when using the L2. A comparison to L1 English data shows this was not only due to the amount of language use or language dominance, but also to the difference in orthographic depth between Dutch and English. An important implication of this finding is that when the same task is used to test and compare different languages, one cannot straightforwardly assume the same cognitive sub processes are involved to an equal degree using the same task in different languages. PMID:29403404

History-dependent ion transport through conical nanopipettes and the implications in energy conversion dynamics at nanoscale interfaces.

PubMed

Li, Yan; Wang, Dengchao; Kvetny, Maksim M; Brown, Warren; Liu, Juan; Wang, Gangli

2015-01-01

The dynamics of ion transport at nanostructured substrate-solution interfaces play vital roles in high-density energy conversion, stochastic chemical sensing and biosensing, membrane separation, nanofluidics and fundamental nanoelectrochemistry. Further advancements in these applications require a fundamental understanding of ion transport at nanoscale interfaces. The understanding of the dynamic or transient transport, and the key physical process involved, is limited, which contrasts sharply with widely studied steady-state ion transport features at atomic and nanometer scale interfaces. Here we report striking time-dependent ion transport characteristics at nanoscale interfaces in current-potential ( I - V ) measurements and theoretical analyses. First, a unique non-zero I - V cross-point and pinched I - V curves are established as signatures to characterize the dynamics of ion transport through individual conical nanopipettes. Second, ion transport against a concentration gradient is regulated by applied and surface electrical fields. The concept of ion pumping or separation is demonstrated via the selective ion transport against concentration gradients through individual nanopipettes. Third, this dynamic ion transport process under a predefined salinity gradient is discussed in the context of nanoscale energy conversion in supercapacitor type charging-discharging, as well as chemical and electrical energy conversion. The analysis of the emerging current-potential features establishes the urgently needed physical foundation for energy conversion employing ordered nanostructures. The elucidated mechanism and established methodology can be generalized into broadly-defined nanoporous materials and devices for improved energy, separation and sensing applications.

History-dependent ion transport through conical nanopipettes and the implications in energy conversion dynamics at nanoscale interfaces

DOE PAGES

Li, Yan; Wang, Dengchao; Kvetny, Maksim M.; ...

2014-08-20

The dynamics of ion transport at nanostructured substrate–solution interfaces play vital roles in high-density energy conversion, stochastic chemical sensing and biosensing, membrane separation, nanofluidics and fundamental nanoelectrochemistry. Advancements in these applications require a fundamental understanding of ion transport at nanoscale interfaces. The understanding of the dynamic or transient transport, and the key physical process involved, is limited, which contrasts sharply with widely studied steady-state ion transport features at atomic and nanometer scale interfaces. Here we report striking time-dependent ion transport characteristics at nanoscale interfaces in current–potential (I–V) measurements and theoretical analyses. First, a unique non-zero I–V cross-point and pinched I–Vmore » curves are established as signatures to characterize the dynamics of ion transport through individual conical nanopipettes. Moreoever, ion transport against a concentration gradient is regulated by applied and surface electrical fields. The concept of ion pumping or separation is demonstrated via the selective ion transport against concentration gradients through individual nanopipettes. Third, this dynamic ion transport process under a predefined salinity gradient is discussed in the context of nanoscale energy conversion in supercapacitor type charging–discharging, as well as chemical and electrical energy conversion. Our analysis of the emerging current–potential features establishes the urgently needed physical foundation for energy conversion employing ordered nanostructures. The elucidated mechanism and established methodology can be generalized into broadly-defined nanoporous materials and devices for improved energy, separation and sensing applications.« less

A Feasibility Study of Burning Waste Paper in Coal-Fired Boilers on Air Force Installations

DTIC Science & Technology

1993-09-01

from coal emissions is known as wet flue - gas desulfurization . This process involves the spraying of pulverized limestone (CaCO3 ) mixed with water...conversion to natural gas fuel or additional air : 13-tion controls . However, both of these options can be very costly, and a 6 less expensive alternative may...into the flue gas . The SO, is absorbed by the spray, creating calcium sulfite (Masters, 1991:349). The process is represented in equation form as CaCO3

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

Waitz, M.; Metz, D.; Lower, J.

Here, wWe investigate the photodouble ionization of H 2 molecules with 400 eV photons. We find that the emitted electrons do not show any sign of two-center interference fringes in their angular emission distributions if considered separately. Conversely, the quasiparticle consisting of both electrons (i.e., the "dielectron") does. The work highlights the fact that nonlocal effects are embedded everywhere in nature where many-particle processes are involved.

Catalytic conversion wood syngas to synthetic aviation turbine fuels over a multifunctional catalyst

Treesearch

Qiangu Yan; Fei Yu; Jian Liu; Jason Street; Jinsen Gao; Zhiyong Cai; Jilei Zhang

2013-01-01

A continuous process involving gasification, syngas cleaning, and Fischer–Tropsch (FT) synthesis was developed to efficiently produce synthetic aviation turbine fuels (SATFs). Oak-tree wood chips were first gasified to syngas over a commercial pilot plant downdraft gasifier. The raw wood syngas contains about 47% N2, 21% CO, 18% H2...

Significant alteration of gene expression in wood decay fungi Postia placenta and Phanerochaete chrysosporium by plant species

Treesearch

Amber Vanden Wymelenberg; Jill Gaskell; Michael Mozuch; Sandra Splinter BonDurant; Grzegorz Sabat; John Ralph; Oleksandr Skyba; Shawn D. Mansfield; Robert A. Blanchette; Igor Grigoriev; Philip J. Kersten; Daniel Cullen

2011-01-01

Identification of specific genes and enzymes involved in conversion of lignocellulosics from an expanding number of potential feedstocks is of growing interest to bioenergy process development. The basidiomycetous wood decay fungi Phanerochaete chrysosporium and Postia placenta are promising in this regard because they are able to utilize a wide range of simple and...

Evaluation of a value prior to pulping-thermomechanical pulp business concept. Part 2.

Treesearch

Ted Bilek; Carl Houtman; Peter Ince

2011-01-01

Value Prior to Pulping (VPP) is a novel biorefining concept for pulp mills that includes hydrolysis extraction of hemicellulose wood sugars and acetic acid from pulpwood prior to pulping. The concept involves conversion of wood sugars via fermentation to fuel ethanol or other chemicals and the use of remaining solid wood material in the pulping process. This paper...

Proinsulin maturation disorder is a contributor to the defect of subsequent conversion to insulin in {beta}-cells

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

Wang, Jie, E-mail: jie.wang2@osumc.edu; Osei, Kwame

2011-07-22

Highlights: {yields} Primary proinsulin maturation disorder is inherent in Ins2{sup +/Akita} islets/{beta}-cells. {yields} A consequence is the inefficient conversion of proinsulin to insulin. {yields} Post-translational defects occur as well in the involved PC1/3 and PC2 convertases. {yields} Proinsulin maturation chaos results in defects in the following conversion process. {yields} A link of the proinsulin maturation disorder and hyperproinsulinemia is suggested. -- Abstract: Disproportionate hyperproinsulinemia is an indicator of {beta}-cell dysfunction in diabetes and the basis underlying this abnormality remains obscure. Recently, we have found proinsulin is an aggregation-prone molecule inherent with a low relative folding rate and maintains a homeostaticmore » balance of natively and plentiful non-natively folded states (i.e., proinsulin homeostasis, PIHO) in normal {beta}-cells as a result of the integration of maturation and disposal processes. PIHO is susceptible to environmental and genetic influences. Perturbation of PIHO produces a number of toxic consequences with known association to {beta}-cell failure in diabetes. To explore whether the perturbation of PIHO has a link to disproportionate hyperproinsulinemia, we investigated proinsulin conversion and the involved prohormone convertase 1/3 (PC1/3) and 2 (PC2) in mouse Ins2{sup +/Akita} islets/{beta}-cells that preserve a primary PIHO disorder due to a mutation (C96Y) in the insulin 2 (Ins2) gene. Our metabolic-labeling studies found an increased ratio of proinsulin to insulin in the cellular or released proteins of Ins2{sup +/Akita} islets. Histological, metabolic-labeling, and RT-PCR analyses revealed decreases of the PC1/3 and PC2 immunoreactivities in the {beta}-cells of Ins2{sup +/Akita} islets in spite of no declines of these two convertases at the transcriptional and translational levels. Immunoblot analyses in cloned Ins2{sup +/Akita} {beta}-cells further confirmed the increased ratio of proinsulin to insulin despite the levels of PC1/3 and PC2 proteins were not reduced somehow. The findings demonstrate that the perturbation of PIHO results in defects in the subsequent conversion process of proinsulin and is a contributor to the occurrence of disproportionate hyperproinsulinemia in diabetes.« less

Keep meaning in conversational coordination

PubMed Central

Cuffari, Elena C.

2014-01-01

Coordination is a widely employed term across recent quantitative and qualitative approaches to intersubjectivity, particularly approaches that give embodiment and enaction central explanatory roles. With a focus on linguistic and bodily coordination in conversational contexts, I review the operational meaning of coordination in recent empirical research and related theorizing of embodied intersubjectivity. This discussion articulates what must be involved in treating linguistic meaning as dynamic processes of coordination. The coordination approach presents languaging as a set of dynamic self-organizing processes and actions on multiple timescales and across multiple modalities that come about and work in certain domains (those jointly constructed in social, interactive, high-order sense-making). These processes go beyond meaning at the level that is available to first-person experience. I take one crucial consequence of this to be the ubiquitously moral nature of languaging with others. Languaging coordinates experience, among other levels of behavior and event. Ethical effort is called for by the automatic autonomy-influencing forces of languaging as coordination. PMID:25520693

Energy analysis of convectively induced wind perturbations

NASA Technical Reports Server (NTRS)

Fuelberg, Henry E.; Buechler, Dennis E.

1989-01-01

Budgets of divergent and rotational components of kinetic energy (KD and KR) are examined for four upper level wind speed maxima that develop during the fourth Atmospheric Variability Experiment (AVE IV) and the first AVE-Severe Environmental Storms and Mesoscale Experiment (AVE-SESAME I). A similar budget analysis is performed for a low-level jet stream during AVE-SESAME I. The energetics of the four upper level speed maxima is found to have several similarities. The dominant source of KD is cross-contour flow by the divergent wind, and KD provides a major source of KR via a conversion process. Conversion from available potential energy provides an additional source of KR in three of the cases. Horizontal maps reveal that the conversions involving KD are maximized in regions poleward of the convection. Low-level jet development during AVE-SESAME I appears to be assisted by convective activity to the west.

Third harmonic from air breakdown plasma induced by nanosecond laser pulses

NASA Astrophysics Data System (ADS)

Stafe, M.; Negutu, C.; Puscas, N. N.

2018-06-01

Harmonic generation is a nonlinear optical effect consisting in frequency up-conversion of intense laser radiation when phase-matching conditions are fulfilled. Here, we study the mechanisms involved in the third harmonic (TH) generation process, the conversion efficiency, and the properties of TH radiation generated in air by focusing infrared linearly polarized nanosecond laser pulses at intensities of the order of TW/cm2. By analyzing the emission from the air breakdown plasma, we demonstrate that filamentary breakdown plasma containing molecular nitrogen ions acts as an optical nonlinear medium enabling generation of TH radiation in the axial direction. The data reveal important properties of the TH radiation: maximum conversion efficiency of 0.04%, sinc2 dependence of the TH intensity on the square root of the pump intensity, and three times smaller divergence and pulse duration of TH as compared to the pump radiation.

Catalytic conversion wood syngas to synthetic aviation turbine fuels over a multifunctional catalyst.

PubMed

Yan, Qiangu; Yu, Fei; Liu, Jian; Street, Jason; Gao, Jinsen; Cai, Zhiyong; Zhang, Jilei

2013-01-01

A continuous process involving gasification, syngas cleaning, and Fischer-Tropsch (FT) synthesis was developed to efficiently produce synthetic aviation turbine fuels (SATFs). Oak-tree wood chips were first gasified to syngas over a commercial pilot plant downdraft gasifier. The raw wood syngas contains about 47% N(2), 21% CO, 18% H(2), 12% CO(2,) 2% CH(4) and trace amounts of impurities. A purification reaction system was designed to remove the impurities in the syngas such as moisture, oxygen, sulfur, ammonia, and tar. The purified syngas meets the requirements for catalytic conversion to liquid fuels. A multi-functional catalyst was developed and tested for the catalytic conversion of wood syngas to SATFs. It was demonstrated that liquid fuels similar to commercial aviation turbine fuels (Jet A) was successfully synthesized from bio-syngas. Copyright © 2012 Elsevier Ltd. All rights reserved.

Physico-chemical and thermochemical studies of the hydrolytic conversion of amorphous tricalcium phosphate into apatite

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

Somrani, Saida; Banu, Mihai; Jemal, Mohamed

2005-05-15

The conversion of amorphous tricalcium phosphate with different hydration ratio into apatite in water at 25 deg. C has been studied by microcalorimetry and several physical-chemical methods. The hydrolytic transformation was dominated by two strong exothermic events. A fast, relatively weak, wetting process and a very slow but strong heat release assigned to a slow internal rehydration and the crystallization of the amorphous phase into an apatite. The exothermic phenomenon related to the rehydration exceeded the crystalline transformation enthalpy. Rehydration occurred before the conversion of the amorphous phase into apatite and determined the advancement of the hydrolytic reaction. The apatiticmore » phases formed evolved slightly with time after their formation. The crystallinity increased whereas the amount of HPO{sub 4}{sup 2-} ion decreased. These data allow a better understanding of the behavior of biomaterials involving amorphous phases such as hydroxyapatite plasma-sprayed coatings.« less

Probing CP violation in $$h\\rightarrow\\gamma\\gamma$$ with converted photons

DOE PAGES

Bishara, Fady; Grossman, Yuval; Harnik, Roni; ...

2014-04-11

We study Higgs diphoton decays, in which both photons undergo nuclear conversion to electron- positron pairs. The kinematic distribution of the two electron-positron pairs may be used to probe the CP violating (CPV) coupling of the Higgs to photons, that may be produced by new physics. Detecting CPV in this manner requires interference between the spin-polarized helicity amplitudes for both conversions. We derive leading order, analytic forms for these amplitudes. In turn, we obtain compact, leading-order expressions for the full process rate. While performing experiments involving photon conversions may be challenging, we use the results of our analysis to constructmore » experimental cuts on certain observables that may enhance sensitivity to CPV. We show that there exist regions of phase space on which sensitivity to CPV is of order unity. As a result, the statistical sensitivity of these cuts are verified numerically, using dedicated Monte-Carlo simulations.« less

The genome and transcriptome of the enteric parasite Entamoeba invadens, a model for encystation

PubMed Central

2013-01-01

Background Several eukaryotic parasites form cysts that transmit infection. The process is found in diverse organisms such as Toxoplasma, Giardia, and nematodes. In Entamoeba histolytica this process cannot be induced in vitro, making it difficult to study. In Entamoeba invadens, stage conversion can be induced, but its utility as a model system to study developmental biology has been limited by a lack of genomic resources. We carried out genome and transcriptome sequencing of E. invadens to identify molecular processes involved in stage conversion. Results We report the sequencing and assembly of the E. invadens genome and use whole transcriptome sequencing to characterize changes in gene expression during encystation and excystation. The E. invadens genome is larger than that of E. histolytica, apparently largely due to expansion of intergenic regions; overall gene number and the machinery for gene regulation are conserved between the species. Over half the genes are regulated during the switch between morphological forms and a key signaling molecule, phospholipase D, appears to regulate encystation. We provide evidence for the occurrence of meiosis during encystation, suggesting that stage conversion may play a key role in recombination between strains. Conclusions Our analysis demonstrates that a number of core processes are common to encystation between distantly related parasites, including meiosis, lipid signaling and RNA modification. These data provide a foundation for understanding the developmental cascade in the important human pathogen E. histolytica and highlight conserved processes more widely relevant in enteric pathogens. PMID:23889909

Catabolism of coniferyl aldehyde, ferulic acid and p-coumaric acid by Saccharomyces cerevisiae yields less toxic products.

PubMed

Adeboye, Peter Temitope; Bettiga, Maurizio; Aldaeus, Fredrik; Larsson, Per Tomas; Olsson, Lisbeth

2015-09-21

Lignocellulosic substrates and pulping process streams are of increasing relevance to biorefineries for second generation biofuels and biochemical production. They are known to be rich in sugars and inhibitors such as phenolic compounds, organic acids and furaldehydes. Phenolic compounds are a group of aromatic compounds known to be inhibitory to fermentative organisms. It is known that inhibition of Sacchromyces cerevisiae varies among phenolic compounds and the yeast is capable of in situ catabolic conversion and metabolism of some phenolic compounds. In an approach to engineer a S. cerevisiae strain with higher tolerance to phenolic inhibitors, we selectively investigated the metabolic conversion and physiological effects of coniferyl aldehyde, ferulic acid, and p-coumaric acid in Saccharomyces cerevisiae. Aerobic batch cultivations were separately performed with each of the three phenolic compounds. Conversion of each of the phenolic compounds was observed on time-based qualitative analysis of the culture broth to monitor various intermediate and final metabolites. Coniferyl aldehyde was rapidly converted within the first 24 h, while ferulic acid and p-coumaric acid were more slowly converted over a period of 72 h. The conversion of the three phenolic compounds was observed to involved several transient intermediates that were concurrently formed and converted to other phenolic products. Although there were several conversion products formed from coniferyl aldehyde, ferulic acid and p-coumaric acid, the conversion products profile from the three compounds were similar. On the physiology of Saccharomyces cerevisiae, the maximum specific growth rates of the yeast was not affected in the presence of coniferyl aldehyde or ferulic acid, but it was significantly reduced in the presence of p-coumaric acid. The biomass yields on glucose were reduced to 73 and 54 % of the control in the presence of coniferyl aldehyde and ferulic acid, respectively, biomass yield increased to 127 % of the control in the presence of p-coumaric acid. Coniferyl aldehyde, ferulic acid and p-coumaric acid and their conversion products were screened for inhibition, the conversion products were less inhibitory than coniferyl aldehyde, ferulic acid and p-coumaric acid, indicating that the conversion of the three compounds by Saccharomyces cerevisiae was also a detoxification process. We conclude that the conversion of coniferyl aldehyde, ferulic acid and p-coumaric acid into less inhibitory compounds is a form of stress response and a detoxification process. We hypothesize that all phenolic compounds are converted by Saccharomyces cerevisiae using the same metabolic process. We suggest that the enhancement of the ability of S. cerevisiae to convert toxic phenolic compounds into less inhibitory compounds is a potent route to developing a S. cerevisiae with superior tolerance to phenolic compounds.

Neural signatures of response planning occur midway through an incoming question in conversation

PubMed Central

Bögels, Sara; Magyari, Lilla; Levinson, Stephen C.

2015-01-01

A striking puzzle about language use in everyday conversation is that turn-taking latencies are usually very short, whereas planning language production takes much longer. This implies overlap between language comprehension and production processes, but the nature and extent of such overlap has never been studied directly. Combining an interactive quiz paradigm with EEG measurements in an innovative way, we show that production planning processes start as soon as possible, that is, within half a second after the answer to a question can be retrieved (up to several seconds before the end of the question). Localization of ERP data shows early activation even of brain areas related to late stages of production planning (e.g., syllabification). Finally, oscillation results suggest an attention switch from comprehension to production around the same time frame. This perspective from interactive language use throws new light on the performance characteristics that language competence involves. PMID:26242909

Evaluation of various procedures transposing global tilted irradiance to horizontal surface irradiance

NASA Astrophysics Data System (ADS)

Housmans, Caroline; Bertrand, Cédric

2017-02-01

Many transposition models have been proposed in the literature to convert solar irradiance on the horizontal plane to that on a tilted plane. The inverse process, i.e. the conversion from tilted to horizontal is investigated here based upon seven months of in-plane global solar irradiance measurements recorded on the roof of the Royal Meteorological Institute of Belgium's radiation tower in Uccle (Longitude 4.35° E, Latitude 50.79° N). Up to three pyranometers mounted on inclined planes of different tilts and orientations were involved in the inverse transposition process. Our results indicate that (1) the tilt to horizontal irradiance conversion is improved when measurements from more than one tilted pyranometer are considered (i.e. by using a multi-pyranometer approach) and (2) the improvement from using an isotropic model to anisotropic models in the inverse transposition problem is not significant.

Ab initio study on the dynamics of furfural at the liquid-solid interfaces

NASA Astrophysics Data System (ADS)

Dang, Hongli; Xue, Wenhua; Shields, Darwin; Liu, Yingdi; Jentoft, Friederike; Resasco, Daniel; Wang, Sanwu

2013-03-01

Catalytic biomass conversion sometimes occurs at the liquid-solid interfaces. We report ab initio molecular dynamics simulations at finite temperatures for the catalytic reactions involving furfural at the water-Pd and water-Cu interfaces. We found that, during the dynamic process, the furan ring of furfural prefers to be parallel to the Pd surface and the aldehyde group tends to be away from the Pd surface. On the other hand, at the water-Cu(111) interface, furfural prefers to be tilted to the Cu surface while the aldehyde group is bonded to the surface. In both cases, interaction of liquid water and furfural is identified. The difference of dynamic process of furfural at the two interfaces suggests different catalytic reaction mechanisms for the conversion of furfural, consistent with the experimental investigations. Supported by DOE (DE-SC0004600). Simulations and calculations were performed on XSED's and NERSC's supercomputers

Unraveling reaction pathways and specifying reaction kinetics for complex systems.

PubMed

Vinu, R; Broadbelt, Linda J

2012-01-01

Many natural and industrial processes involve a complex set of competing reactions that include several different species. Detailed kinetic modeling of such systems can shed light on the important pathways involved in various transformations and therefore can be used to optimize the process conditions for the desired product composition and properties. This review focuses on elucidating the various components involved in modeling the kinetics of pyrolysis and oxidation of polymers. The elementary free radical steps that constitute the chain reaction mechanism of gas-phase/nonpolar liquid-phase processes are outlined. Specification of the rate coefficients of the various reaction families, which is central to the theme of kinetics, is described. Construction of the reaction network on the basis of the types of end groups and reactive moieties in a polymer chain is discussed. Modeling frameworks based on the method of moments and kinetic Monte Carlo are evaluated using illustrations. Finally, the prospects and challenges in modeling biomass conversion are addressed.

Feedstock Supply System Design and Economics for Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels: Conversion Pathway: Biological Conversion of Sugars to Hydrocarbons The 2017 Design Case

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

Kevin Kenney; Kara G. Cafferty; Jacob J. Jacobson

The U.S. Department of Energy promotes the production of a range of liquid fuels and fuel blendstocks from lignocellulosic biomass feedstocks by funding fundamental and applied research that advances the state of technology in biomass collection, conversion, and sustainability. As part of its involvement in this program, the Idaho National Laboratory (INL) investigates the feedstock logistics economics and sustainability of these fuels. Between 2000 and 2012, INL conducted a campaign to quantify the economics and sustainability of moving biomass from standing in the field or stand to the throat of the biomass conversion process. The goal of this program wasmore » to establish the current costs based on conventional equipment and processes, design improvements to the current system, and to mark annual improvements based on higher efficiencies or better designs. The 2012 programmatic target was to demonstrate a delivered biomass logistics cost of $35/dry ton. This goal was successfully achieved in 2012 by implementing field and process demonstration unit-scale data from harvest, collection, storage, preprocessing, handling, and transportation operations into INL’s biomass logistics model. Looking forward to 2017, the programmatic target is to supply biomass to the conversion facilities at a total cost of $80/dry ton and on specification with in-feed requirements. The goal of the 2017 Design Case is to enable expansion of biofuels production beyond highly productive resource areas by breaking the reliance of cost-competitive biofuel production on a single, abundant, low-cost feedstock. If this goal is not achieved, biofuel plants are destined to be small and/or clustered in select regions of the country that have a lock on low-cost feedstock. To put the 2017 cost target into perspective of past accomplishments of the cellulosic ethanol pathway, the $80 target encompasses total delivered feedstock cost, including both grower payment and logistics costs, while meeting all conversion in-feed quality targets. The 2012 $35 programmatic target included only logistics costs with a limited focus on biomass quality« less

Magnetic field reconnection. [energy conversion in space plasma

NASA Technical Reports Server (NTRS)

Sonnerup, U. O.

1979-01-01

A reasonably detailed description is obtained of the current status of our understanding of magnetic field reconnection. The picture that emerges is of a process, simple in concept but extremely complicated and multifaceted in detail. Nonlinear MHD processes in the external flow region, governed by distant boundary conditions, are coupled to nonlinear microscopic plasma processes in the diffusion region, in a manner not clearly understood. It appears that reconnection may operate in entirely different ways for different plasma parameters and different external boundary conditions. Steady reconnection may be allowed in some cases, forbidden in others, with intermediate situations involving impulsive or pulsative events.

Laser synthesized super-hydrophobic conducting carbon with broccoli-type morphology as a counter-electrode for dye sensitized solar cells.

PubMed

Gokhale, Rohan; Agarkar, Shruti; Debgupta, Joyashish; Shinde, Deodatta; Lefez, Benoit; Banerjee, Abhik; Jog, Jyoti; More, Mahendra; Hannoyer, Beatrice; Ogale, Satishchandra

2012-11-07

A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode.

Production of chemicals and fuels from biomass

DOEpatents

Woods, Elizabeth; Qiao, Ming; Myren, Paul; Cortright, Randy D.; Kania, John

2015-12-15

Described are methods, reactor systems, and catalysts for converting biomass to fuels and chemicals in a batch and/or continuous process. The process generally involves the conversion of water insoluble components of biomass, such as hemicellulose, cellulose and lignin, to volatile C.sub.2+O.sub.1-2 oxygenates, such as alcohols, ketones, cyclic ethers, esters, carboxylic acids, aldehydes, and mixtures thereof. In certain applications, the volatile C.sub.2+O.sub.1-2 oxygenates can be collected and used as a final chemical product, or used in downstream processes to produce liquid fuels, chemicals and other products.

Direct Conversion of Energy.

ERIC Educational Resources Information Center

Corliss, William R.

This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Direct energy conversion involves energy transformation without moving parts. The concepts of direct and dynamic energy conversion plus the laws governing energy conversion are investigated. Among the topics…

STATISTICAL ANALYSIS OF SNAP 10A THERMOELECTRIC CONVERTER ELEMENT PROCESS DEVELOPMENT VARIABLES

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

Fitch, S.H.; Morris, J.W.

1962-12-15

Statistical analysis, primarily analysis of variance, was applied to evaluate several factors involved in the development of suitable fabrication and processing techniques for the production of lead telluride thermoelectric elements for the SNAP 10A energy conversion system. The analysis methods are described as to their application for determining the effects of various processing steps, estabIishing the value of individual operations, and evaluating the significance of test results. The elimination of unnecessary or detrimental processing steps was accomplished and the number of required tests was substantially reduced by application of these statistical methods to the SNAP 10A production development effort. (auth)

Two-dimensional correlation and codistribution spectroscopy (2DCOS and 2DCDS) analyses of time-dependent ATR IR spectra of d-glucose anomers undergoing mutarotation process in water.

PubMed

Noda, Isao

2018-05-15

Two cyclic diastereoisomeric structures, known as α- and β-anomers of d-glucose with different configurations around C1 with OH groups in axial or equitroial positions, undergo the mutarotation conversion to each other in water. Two-dimensional correlation and codistribution spectroscopy (2DCOS and 2DCDS) analyses were applied to the time-dependent ATR IR spectra of aqueous solutions of α- and β-d-glucose undergoing such mutarotation conversion. 2DCOS analysis reveals that the increase and decrease in the IR intensities after the dissolution of α- or β-d-glucose are not fully synchronized, suggesting the mutarotation of d-glucose in water is not a simple binary conversion process but a multi-step reaction involving an intermediate species with a finite and observable concentration level and lifetime. 2DCDS analysis of the time-dependent ATR IR spectra clearly demonstrated the presence of intermediate species contributing to the band positions overlapped close to bands for α- and β-d-glucose. The fact that band positions identified for the intermediate species for α- to β-d-glucose conversion are the same for the reverse reaction suggests that they arise from the same species, most likely the open-ring structure produced by the hydrolysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Goals of care conversation teaching in residency - a cross-sectional survey of postgraduate program directors.

PubMed

Roze des Ordons, Amanda; Kassam, Aliya; Simon, Jessica

2017-01-06

Residents are commonly involved in establishing goals of care for hospitalized patients. While education can improve the quality of these conversations, whether and how postgraduate training programs integrate such teaching into their curricula is not well established. The objective of this study was to characterize perceptions of current teaching and assessment of goals of care conversations, and program director interest in associated curricular integration. An electronic survey was sent to all postgraduate program directors at the University of Calgary. Quantitative data was analyzed using descriptive statistics and qualitative comments were analyzed using thematic analysis. The survey response rate was 34% (22/64). Formal goals of care conversation teaching is incorporated into 63% of responding programs, and most commonly involves lectures. Informal teaching occurs in 86% of programs, involving discussion, direct observation and role modeling in the clinical setting. Seventy-three percent of programs assess goals of care conversation skills, mostly in the clinical setting through feedback. Program directors believe that over two-thirds of clinical faculty are prepared to teach goals of care conversations, and are interested in resources to teach and assess goals of care conversations. Themes that emerged include 1) general perceptions, 2) need for teaching, 3) ideas for teaching, and 4) assessment of goals of care conversations. The majority of residency training programs at the University of Calgary incorporate some goals of care conversation teaching and assessment into their curricula. Program directors are interested in resources to improve teaching and assessment of goals of care conversations.

Probing ultrafast ππ*/nπ* internal conversion in organic chromophores via K-edge resonant absorption

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

Wolf, T. J. A.; Myhre, R. H.; Cryan, J. P.

Many photoinduced processes including photosynthesis and human vision happen in organic molecules and involve coupled femtosecond dynamics of nuclei and electrons. Organic molecules with heteroatoms often possess an important excited-state relaxation channel from an optically allowed ππ* to a dark nπ* state. The ππ*/nπ* internal conversion is difficult to investigate, as most spectroscopic methods are not exclusively sensitive to changes in the excited-state electronic structure. Here, we report achieving the required sensitivity by exploiting the element and site specificity of near-edge soft X-ray absorption spectroscopy. As a hole forms in the n orbital during ππ*/nπ* internal conversion, the absorption spectrummore » at the heteroatom K-edge exhibits an additional resonance. We demonstrate the concept using the nucleobase thymine at the oxygen K-edge, and unambiguously show that ππ*/nπ* internal conversion takes place within (60 ± 30) fs. Furthermore, high-level-coupled cluster calculations confirm the method’s impressive electronic structure sensitivity for excited-state investigations.« less

Probing ultrafast ππ*/nπ* internal conversion in organic chromophores via K-edge resonant absorption

DOE PAGES

Wolf, T. J. A.; Myhre, R. H.; Cryan, J. P.; ...

2017-06-22

Many photoinduced processes including photosynthesis and human vision happen in organic molecules and involve coupled femtosecond dynamics of nuclei and electrons. Organic molecules with heteroatoms often possess an important excited-state relaxation channel from an optically allowed ππ* to a dark nπ* state. The ππ*/nπ* internal conversion is difficult to investigate, as most spectroscopic methods are not exclusively sensitive to changes in the excited-state electronic structure. Here, we report achieving the required sensitivity by exploiting the element and site specificity of near-edge soft X-ray absorption spectroscopy. As a hole forms in the n orbital during ππ*/nπ* internal conversion, the absorption spectrummore » at the heteroatom K-edge exhibits an additional resonance. We demonstrate the concept using the nucleobase thymine at the oxygen K-edge, and unambiguously show that ππ*/nπ* internal conversion takes place within (60 ± 30) fs. Furthermore, high-level-coupled cluster calculations confirm the method’s impressive electronic structure sensitivity for excited-state investigations.« less

Conceptualizing the therapist's role in therapy in psychosis.

PubMed

Dilks, Sarah; Tasker, Fiona; Wren, Bernadette

2013-09-01

This paper reports on a subset of findings from a wider ranging grounded theory analysis of therapy and recovery processes in psychosis. It describes therapist activities involved in maintaining an observational perspective during therapy and the links between these and other therapist activities. Grounded theory was used to examine the qualitative data collected. An initial sample of 19 taped therapy sessions and 23 interviews with psychologists and their clients was collected. This sample was extended through the collection of three further interviews with psychoanalytically aware psychologists. The data were analysed using grounded theory. A grounded theory model of therapy processes in psychosis was developed that conceptualized therapist actions as providing an observational scaffold to support the client's efforts in moving to new perspectives on their situation. Consistent with the understanding of the core therapy activity as a dialogical process, this set of therapist actions was understood as occurring alongside other therapist activities involved in managing emotion and building a relationship in therapy. The central activity of therapy in psychosis was understood as a dialogical process continuously negotiated between therapist and client in conversation and was conceptually summarized in the grounded theory as 'building bridges to observational perspectives'. However, the active and strategic efforts of psychologists to sustain the dialogue implied a particular assumption of responsibility for maintaining this process. In particular, therapists appeared to be 'working to maintain observational perspectives', 'managing emotion', and 'doing relationship' during the therapy conversation as part of the joint effort with clients to build bridges to new observational perspectives on distress and psychosis. © 2012 The British Psychological Society.

Conversion of PCDP Dialogs.

ERIC Educational Resources Information Center

Bork, Alfred M.

An introduction to the problems involved in conversion of computer dialogues from one computer language to another is presented. Conversion of individual dialogues by complete rewriting is straightforward, if tedious. To make a general conversion of a large group of heterogeneous dialogue material from one language to another at one step is more…

Adaptive Feedback Improving Learningful Conversations at Workplace

ERIC Educational Resources Information Center

Gaeta, Matteo; Mangione, Giuseppina Rita; Miranda, Sergio; Orciuoli, Francesco

2013-01-01

This work proposes the definition of an Adaptive Conversation-based Learning System (ACLS) able to foster computer-mediated tutorial dialogues at the workplace in order to increase the probability to generate meaningful learning during conversations. ACLS provides a virtual assistant selecting the best partner to involve in the conversation and…

Conversation after Right Hemisphere Brain Damage: Motivations for Applying Conversation Analysis

ERIC Educational Resources Information Center

Barnes, Scott; Armstrong, Elizabeth

2010-01-01

Despite the well documented pragmatic deficits that can arise subsequent to Right Hemisphere Brain Damage (RHBD), few researchers have directly studied everyday conversations involving people with RHBD. In recent years, researchers have begun applying Conversation Analysis (CA) to the everyday talk of people with aphasia. This research programme…

A Cooperative Conversion Project from Vertical File Hardcopy to Jacketed Microfiche.

ERIC Educational Resources Information Center

Worden, Diane D.

1981-01-01

Describes a cooperative project to convert a library's hardcopy materials to microfiche, including the steps involved in conversion, conversion costs, sources of funding, and staff performance rates. Six references are listed. (FM)

History-dependent ion transport through conical nanopipettes and the implications in energy conversion dynamics at nanoscale interfaces† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c4sc02195a Click here for additional data file.

PubMed Central

Li, Yan; Wang, Dengchao; Kvetny, Maksim M.; Brown, Warren; Liu, Juan

2015-01-01

The dynamics of ion transport at nanostructured substrate–solution interfaces play vital roles in high-density energy conversion, stochastic chemical sensing and biosensing, membrane separation, nanofluidics and fundamental nanoelectrochemistry. Further advancements in these applications require a fundamental understanding of ion transport at nanoscale interfaces. The understanding of the dynamic or transient transport, and the key physical process involved, is limited, which contrasts sharply with widely studied steady-state ion transport features at atomic and nanometer scale interfaces. Here we report striking time-dependent ion transport characteristics at nanoscale interfaces in current–potential (I–V) measurements and theoretical analyses. First, a unique non-zero I–V cross-point and pinched I–V curves are established as signatures to characterize the dynamics of ion transport through individual conical nanopipettes. Second, ion transport against a concentration gradient is regulated by applied and surface electrical fields. The concept of ion pumping or separation is demonstrated via the selective ion transport against concentration gradients through individual nanopipettes. Third, this dynamic ion transport process under a predefined salinity gradient is discussed in the context of nanoscale energy conversion in supercapacitor type charging–discharging, as well as chemical and electrical energy conversion. The analysis of the emerging current–potential features establishes the urgently needed physical foundation for energy conversion employing ordered nanostructures. The elucidated mechanism and established methodology can be generalized into broadly-defined nanoporous materials and devices for improved energy, separation and sensing applications. PMID:28706626

Ultrafast photophysics of transition metal complexes.

PubMed

Chergui, Majed

2015-03-17

The properties of transition metal complexes are interesting not only for their potential applications in solar energy conversion, OLEDs, molecular electronics, biology, photochemistry, etc. but also for their fascinating photophysical properties that call for a rethinking of fundamental concepts. With the advent of ultrafast spectroscopy over 25 years ago and, more particularly, with improvements in the past 10-15 years, a new area of study was opened that has led to insightful observations of the intramolecular relaxation processes such as internal conversion (IC), intersystem crossing (ISC), and intramolecular vibrational redistribution (IVR). Indeed, ultrafast optical spectroscopic tools, such as fluorescence up-conversion, show that in many cases, intramolecular relaxation processes can be extremely fast and even shorter than time scales of vibrations. In addition, more and more examples are appearing showing that ultrafast ISC rates do not scale with the magnitude of the metal spin-orbit coupling constant, that is, that there is no heavy-atom effect on ultrafast time scales. It appears that the structural dynamics of the system and the density of states play a crucial role therein. While optical spectroscopy delivers an insightful picture of electronic relaxation processes involving valence orbitals, the photophysics of metal complexes involves excitations that may be centered on the metal (called metal-centered or MC) or the ligand (called ligand-centered or LC) or involve a transition from one to the other or vice versa (called MLCT or LMCT). These excitations call for an element-specific probe of the photophysics, which is achieved by X-ray absorption spectroscopy. In this case, transitions from core orbitals to valence orbitals or higher allow probing the electronic structure changes induced by the optical excitation of the valence orbitals, while also delivering information about the geometrical rearrangement of the neighbor atoms around the atom of interest. With the emergence of new instruments such as X-ray free electron lasers (XFELs), it is now possible to perform ultrafast laser pump/X-ray emission probe experiments. In this case, one probes the density of occupied states. These core-level spectroscopies and other emerging ones, such as photoelectron spectroscopy of solutions, are delivering a hitherto unseen degree of detail into the photophysics of metal-based molecular complexes. In this Account, we will give examples of applications of the various methods listed above to address specific photophysical processes.

Ryan Davis | NREL

Science.gov Websites

design TEA LCA Biochemical conversion process pathways Algal biomass production and conversion pathways Production," Green Chemistry (2015) Process Design and Economics for the Conversion of Lignocellulosic Production," Applied Energy (2011) Process Design and Economics for Biochemical Conversion of

Biomass conversion processes for energy and fuels

NASA Astrophysics Data System (ADS)

Sofer, S. S.; Zaborsky, O. R.

The book treats biomass sources, promising processes for the conversion of biomass into energy and fuels, and the technical and economic considerations in biomass conversion. Sources of biomass examined include crop residues and municipal, animal and industrial wastes, agricultural and forestry residues, aquatic biomass, marine biomass and silvicultural energy farms. Processes for biomass energy and fuel conversion by direct combustion (the Andco-Torrax system), thermochemical conversion (flash pyrolysis, carboxylolysis, pyrolysis, Purox process, gasification and syngas recycling) and biochemical conversion (anaerobic digestion, methanogenesis and ethanol fermentation) are discussed, and mass and energy balances are presented for each system.

Biocatalysis for the production of industrial products and functional foods from rice and other agricultural produce.

PubMed

Akoh, Casimir C; Chang, Shu-Wei; Lee, Guan-Chiun; Shaw, Jei-Fu

2008-11-26

Many industrial products and functional foods can be obtained from cheap and renewable raw agricultural materials. For example, starch can be converted to bioethanol as biofuel to reduce the current demand for petroleum or fossil fuel energy. On the other hand, starch can also be converted to useful functional ingredients, such as high fructose and high maltose syrups, wine, glucose, and trehalose. The conversion process involves fermentation by microorganisms and use of biocatalysts such as hydrolases of the amylase superfamily. Amylases catalyze the process of liquefaction and saccharification of starch. It is possible to perform complete hydrolysis of starch by using the fusion product of both linear and debranching thermostable enzymes. This will result in saving energy otherwise needed for cooling before the next enzyme can act on the substrate, if a sequential process is utilized. Recombinant enzyme technology, protein engineering, and enzyme immobilization are powerful tools available to enhance the activity of enzymes, lower the cost of enzyme through large scale production in a heterologous host, increase their thermostability, improve pH stability, enhance their productivity, and hence making it competitive with the chemical processes involved in starch hydrolysis and conversions. This review emphasizes the potential of using biocatalysis for the production of useful industrial products and functional foods from cheap agricultural produce and transgenic plants. Rice was selected as a typical example to illustrate many applications of biocatalysis in converting low-value agricultural produce to high-value commercial food and industrial products. The greatest advantages of using enzymes for food processing and for industrial production of biobased products are their environmental friendliness and consumer acceptance as being a natural process.

Rectenna session: Micro aspects. [energy conversion

NASA Technical Reports Server (NTRS)

Gutmann, R. J.

1980-01-01

Two micro aspects of the rectenna design are addressed: evaluation of the degradation in net rectenna RF to DC conversion efficiency due to power density variations across the rectenna (power combining analysis) and design of Yagi-Uda receiving elements to reduce rectenna cost by decreasing the number of conversion circuits (directional receiving elements). The first of these micro aspects involves resolving a fundamental question of efficiency potential with a rectenna, while the second involves a design modification with a large potential cost saving.

Design of multi-energy Helds coupling testing system of vertical axis wind power system

NASA Astrophysics Data System (ADS)

Chen, Q.; Yang, Z. X.; Li, G. S.; Song, L.; Ma, C.

2016-08-01

The conversion efficiency of wind energy is the focus of researches and concerns as one of the renewable energy. The present methods of enhancing the conversion efficiency are mostly improving the wind rotor structure, optimizing the generator parameters and energy storage controller and so on. Because the conversion process involves in energy conversion of multi-energy fields such as wind energy, mechanical energy and electrical energy, the coupling effect between them will influence the overall conversion efficiency. In this paper, using system integration analysis technology, a testing system based on multi-energy field coupling (MEFC) of vertical axis wind power system is proposed. When the maximum efficiency of wind rotor is satisfied, it can match to the generator function parameters according to the output performance of wind rotor. The voltage controller can transform the unstable electric power to the battery on the basis of optimizing the parameters such as charging times, charging voltage. Through the communication connection and regulation of the upper computer system (UCS), it can make the coupling parameters configure to an optimal state, and it improves the overall conversion efficiency. This method can test the whole wind turbine (WT) performance systematically and evaluate the design parameters effectively. It not only provides a testing method for system structure design and parameter optimization of wind rotor, generator and voltage controller, but also provides a new testing method for the whole performance optimization of vertical axis wind energy conversion system (WECS).

"I just think that we should be informed" a qualitative study of family involvement in advance care planning in nursing homes.

PubMed

Thoresen, Lisbeth; Lillemoen, Lillian

2016-11-10

As part of the research project "End-of-life Communication in Nursing Homes. Patient Preferences and Participation", we have studied how Advance Care Planning (ACP) is carried out in eight Norwegian nursing homes. The concept of ACP is a process for improving patient autonomy and communication in the context of progressive illness, anticipated deterioration and end-of-life care. While an individualistic autonomy based attitude is at the fore in most studies on ACP, there is a lack of empirical studies on how family members' participation and involvement in ACP- conversations may promote nursing home patients' participation in decisions on future treatment and end-of-life care. Based on empirical data and family ethics perspectives, the purpose of this study is to add insights to the complexity of ACP-conversations and illuminate how a family ethics perspective may improve the quality of the ACP and promote nursing home patients' participation in advance care planning. Participant observations of ACP-conversations in eight nursing homes. The observations were followed by interviews with patients and relatives together on how they experienced being part of the conversation, and expressing their views on future medical treatment, hospitalization and end-of-life issues. We found that the way nursing home patients and relatives are connected and related to each other, constitutes an intertwined unit. Further, we found that relatives' involvement and participation in ACP- conversations is significant to uncover, and give the nursing home staff insight into, what is important in the nursing home patient's life at the time. The third analytical theme is patients' and relatives' shared experiences of the dying and death of others. Drawing on past experiences can be a way of introducing or talking about death. An individual autonomy approach in advance care planning should be complemented with a family ethics approach. To be open to family ethics when planning for the patient's future in the nursing home is to be open to diversity and nuances and to the significance of the patient's former life and experiences.

Rectenna System Design. [energy conversion solar power satellites

NASA Technical Reports Server (NTRS)

Woodcock, G. R.; Andryczyk, R. W.

1980-01-01

The fundamental processes involved in the operation of the rectenna system designed for the solar power satellite system are described. The basic design choices are presented based on the desired microwave rf field concentration prior to rectification and based on the ground clearance requirements for the rectenna structure. A nonconcentrating inclined planar panel with a 2 meter minimum clearance configuration is selected as a representative of the typical rectenna.

Investing in Their Future: Portland’s Purchase and Conversion of an LED Street Lighting System

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

Kinzey, B. R.; Rosinbum, T.

During the ongoing process of converting its streetlights from high-pressure sodium to LED, the city of Portland, Oregon, purchased a large portion of its street lighting system and encountered a range of issues among the stakeholders. This report identifies some of the challenges involved and discusses how they were addressed, in order to help inform and facilitate future lighting transitions elsewhere.

Arsenic (+3 Oxidation State) Methyltransferase and the Methylation of Arsenicals

PubMed Central

Thomas, David J.; Li, Jiaxin; Waters, Stephen B.; Xing, Weibing; Adair, Blakely M.; Drobna, Zuzana; Devesa, Vicenta; Styblo, Miroslav

2008-01-01

Metabolic conversion of inorganic arsenic into methylated products is a multistep process that yields mono-, di-, and trimethylated arsenicals. In recent years, it has become apparent that formation of methylated metabolites of inorganic arsenic is not necessarily a detoxification process. Intermediates and products formed in this pathway may be more reactive and toxic than inorganic arsenic. Like all metabolic pathways, understanding the pathway for arsenic methylation involves identification of each individual step in the process and the characterization of the molecules which participate in each step. Among several arsenic methyltransferases that have been identified, arsenic (+3 oxidation state) methyltransferase is the one best characterized at the genetic and functional levels. This review focuses on phylogenetic relationships in the deuterostomal lineage for this enzyme and on the relation between genotype for arsenic (+3 oxidation state) methyltransferase and phenotype for conversion of inorganic arsenic to methylated metabolites. Two conceptual models for function of arsenic (+3 oxidation state) methyltransferase which posit different roles for cellular reductants in the conversion of inorganic arsenic to methylated metabolites are compared. Although each model accurately represents some aspects of enzyme’s role in the pathway for arsenic methylation, neither model is a fully satisfactory representation of all the steps in this metabolic pathway. Additional information on the structure and function of the enzyme will be needed to develop a more comprehensive model for this pathway. PMID:17202581

Novel electrochemical process for coal conversion

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

Farooque, M.

1989-07-01

The feasibility of two distinctly different routes to coal conversion at low severity conditions was investigated. An electrochemical approach utilizing both the electro-oxidation and electro-reduction routes was employed. The electro-oxidation route consists of an electrochemical reaction involving H{sub 2}O and coal, leading to the breakup of coal molecules. The observed reaction rate has been explained as a combination of the coal and pyrite electro-oxidation currents. Organic sulfur has been identified as the contributing factor for the observation of more than 100% H{sub 2} production current efficiency with several coal samples. Also, an attractive coal pre-treatment process has been identified whichmore » results in production of useful products and simultaneous upgrading of the coal. Electrochemical oxidation of coal with H{sub 2}O leads to the production of hydrogen, CO{sub 2}, simultaneous removal of pyritic sulfur, and significant reduction of ash content. There is also indirect evidence that the organic sulfur may be removed in the process. A preliminary economic evaluation of this process has projected a cost advantage of > $8 per ton of Illinois {number sign}2 coal. A lab-scale cell has been successfully employed in this study for generating process data useful for future design calculations. This study also explored the electro-reduction route of coal conversion and has successfully demonstrated production of liquid products from different coal types at low severity conditions. A variety of aliphatic and aromatic compounds have been identified in the products. Coal type appeared to be the most important parameter affecting the product spectrum. 32 refs., 26 figs., 19 tabs.« less

Novel grid-based optical Braille conversion: from scanning to wording

NASA Astrophysics Data System (ADS)

Yoosefi Babadi, Majid; Jafari, Shahram

2011-12-01

Grid-based optical Braille conversion (GOBCO) is explained in this article. The grid-fitting technique involves processing scanned images taken from old hard-copy Braille manuscripts, recognising and converting them into English ASCII text documents inside a computer. The resulted words are verified using the relevant dictionary to provide the final output. The algorithms employed in this article can be easily modified to be implemented on other visual pattern recognition systems and text extraction applications. This technique has several advantages including: simplicity of the algorithm, high speed of execution, ability to help visually impaired persons and blind people to work with fax machines and the like, and the ability to help sighted people with no prior knowledge of Braille to understand hard-copy Braille manuscripts.

Quantum and Multidimensional Explanations in a Neurobiological Context of Mind.

PubMed

Korf, Jakob

2015-08-01

This article examines the possible relevance of physical-mathematical multidimensional or quantum concepts aiming at understanding the (human) mind in a neurobiological context. Some typical features of the quantum and multidimensional concepts are briefly introduced, including entanglement, superposition, holonomic, and quantum field theories. Next, we consider neurobiological principles, such as the brain and its emerging (physical) mind, evolutionary and ontological origins, entropy, syntropy/neg-entropy, causation, and brain energy metabolism. In many biological processes, including biochemical conversions, protein folding, and sensory perception, the ubiquitous involvement of quantum mechanisms is well recognized. Quantum and multidimensional approaches might be expected to help describe and model both brain and mental processes, but an understanding of their direct involvement in mental activity, that is, without mediation by molecular processes, remains elusive. More work has to be done to bridge the gap between current neurobiological and physical-mathematical concepts with their associated quantum-mind theories. © The Author(s) 2014.

Long-term memory, neurogenesis, and signal novelty.

PubMed

Sokolov, E N; Nezlina, N I

2004-10-01

According to our suggested hypothesis, long-term memory is a collection of "gnostic units," selectively tuned to past events. The formation of long-term memory occurs with the involvement of constantly appearing new neurons which differentiate from stem cells during the process of neurogenesis, in particular in adults. Conversion of precursor neurons into "gnostic units" selective in relation to ongoing events, supplemented by the involvement of hippocampal "novelty neurons," which increase the flow of information needing to be fixed in long-term memory. "Gnostic units" form before the informational processes occurring in the ventral ("what?") and dorsal ("where?") systems. Formation of new "gnostic units" selectively tuned to a particular event results from the combination of excitation of the detector for stimulus characteristics and the novelty signal generated by "novelty neurons" in the hippocampus.

Optimized breeding strategies for multiple trait integration: II. Process efficiency in event pyramiding and trait fixation.

PubMed

Peng, Ting; Sun, Xiaochun; Mumm, Rita H

2014-01-01

Multiple trait integration (MTI) is a multi-step process of converting an elite variety/hybrid for value-added traits (e.g. transgenic events) through backcross breeding. From a breeding standpoint, MTI involves four steps: single event introgression, event pyramiding, trait fixation, and version testing. This study explores the feasibility of marker-aided backcross conversion of a target maize hybrid for 15 transgenic events in the light of the overall goal of MTI of recovering equivalent performance in the finished hybrid conversion along with reliable expression of the value-added traits. Using the results to optimize single event introgression (Peng et al. Optimized breeding strategies for multiple trait integration: I. Minimizing linkage drag in single event introgression. Mol Breed, 2013) which produced single event conversions of recurrent parents (RPs) with ≤8 cM of residual non-recurrent parent (NRP) germplasm with ~1 cM of NRP germplasm in the 20 cM regions flanking the event, this study focused on optimizing process efficiency in the second and third steps in MTI: event pyramiding and trait fixation. Using computer simulation and probability theory, we aimed to (1) fit an optimal breeding strategy for pyramiding of eight events into the female RP and seven in the male RP, and (2) identify optimal breeding strategies for trait fixation to create a 'finished' conversion of each RP homozygous for all events. In addition, next-generation seed needs were taken into account for a practical approach to process efficiency. Building on work by Ishii and Yonezawa (Optimization of the marker-based procedures for pyramiding genes from multiple donor lines: I. Schedule of crossing between the donor lines. Crop Sci 47:537-546, 2007a), a symmetric crossing schedule for event pyramiding was devised for stacking eight (seven) events in a given RP. Options for trait fixation breeding strategies considered selfing and doubled haploid approaches to achieve homozygosity as well as seed chipping and tissue sampling approaches to facilitate genotyping. With selfing approaches, two generations of selfing rather than one for trait fixation (i.e. 'F2 enrichment' as per Bonnett et al. in Strategies for efficient implementation of molecular markers in wheat breeding. Mol Breed 15:75-85, 2005) were utilized to eliminate bottlenecking due to extremely low frequencies of desired genotypes in the population. The efficiency indicators such as total number of plants grown across generations, total number of marker data points, total number of generations, number of seeds sampled by seed chipping, number of plants requiring tissue sampling, and number of pollinations (i.e. selfing and crossing) were considered in comparisons of breeding strategies. A breeding strategy involving seed chipping and a two-generation selfing approach (SC + SELF) was determined to be the most efficient breeding strategy in terms of time to market and resource requirements. Doubled haploidy may have limited utility in trait fixation for MTI under the defined breeding scenario. This outcome paves the way for optimizing the last step in the MTI process, version testing, which involves hybridization of female and male RP conversions to create versions of the converted hybrid for performance evaluation and possible commercial release.

Tilt to horizontal global solar irradiance conversion: application to PV systems data

NASA Astrophysics Data System (ADS)

Housmans, Caroline; Leloux, Jonathan; Bertrand, Cédric

2017-04-01

Many transposition models have been proposed in the literature to convert solar irradiance on the horizontal plane to that on a tilted plane requiring that at least two of the three solar components (i.e. global, direct and diffuse) are known. When only global irradiance measurements are available, the conversion from horizontal to tilted planes is still possible but in this case transposition models have to be coupled with decomposition models (i.e. models that predict the direct and diffuse components from the global one). Here, two different approaches have been considered to solve the reverse process, i.e. the conversion from tilted to horizontal: (i) one-sensor approach and (ii) multi-sensors approach. Because only one tilted plane is involved in the one-sensor approach, a decomposition model need to be coupled with a transposition model to solve the problem. By contrast, at least two tilted planes being considered in the multi-sensors approach, only a transposition model is required to perform the conversion. First, global solar irradiance measurements recorded on the roof of the Royal Meteorological Institute of Belgium's radiation tower in Uccle were used to evaluate the performance of both approaches. Four pyranometers (one mounted in the horizontal plane and three on inclined surfaces with different tilts and orientations) were involved in the validation exercise. Second, the inverse transposition was applied to tilted global solar irradiance values retrieved from the energy production registered at residential PV systems located in the vicinity of Belgian radiometric stations operated by RMI (for validation purposes).

77 FR 59628 - Rental Assistance Demonstration: Processing of Conversion Requests Submitted Under the Partial...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-28

... Demonstration: Processing of Conversion Requests Submitted Under the Partial Rental Assistance Demonstration... provides the opportunity to test the conversion of public housing and other HUD-assisted properties to long... have increased housing choices after the conversion; and the overall impact of conversion on the...

A coupled CFD and two-phase substrate kinetic model for enzymatic hydrolysis of lignocellulose

NASA Astrophysics Data System (ADS)

Danes, Nicholas; Sitaraman, Hariswaran; Stickel, Jonathan; Sprague, Michael

2017-11-01

Cost-effective production of fuels from lignocellulosic biomass is an important subject of research in order to meet the world's current and future energy demands. Enzymatic hydrolysis is one of the several steps in the biochemical conversion of biomass into fuels. This process involves the interplay of non-Newtonian fluid dynamics that happen over tens of seconds coupled with chemical reactions that happen over several hours. In this work, we present a coupled CFD-reaction model for conversion of cellulose to sugars in a benchtop mixer reactor. A subcycling approach is used to circumvent the large time scale disparity between fluid dynamics and reactions. We will present a validation study of our simulations with experiments for well-mixed and stratified reactor scenarios along with predictions for conversion rates and product concentrations at varying impeller speeds and in scaled-up reactors. This work is funded by the Bioenergy Technology Office of DOE and the NSF's Enriched Doctoral Training program (DMS-1551229).

Separation and conversion dynamics of nuclear-spin isomers of gaseous methanol

PubMed Central

Sun, Zhen-Dong; Ge, Meihua; Zheng, Yujun

2015-01-01

All symmetrical molecules with non-zero nuclear spin exist in nature as nuclear-spin isomers (NSIs). However, owing to the lack of experimental information, knowledge is rare about interconversions of NSIs of gaseous molecules with torsional symmetry. Here we report our separation and conversion observations on NSI-torsion-specific transition systems of gaseous methanol from a light-induced drift experiment involving partially spatial separation of the ortho and para isomers. We find that vibrationally excited molecules of the methanol spin isomer have a smaller collision cross-section than their ground-state counterparts. Interconversion of the enriched ortho isomer with the para isomer, which is generally considered improbable, has been quantitatively studied by sensitive detections of the spectral intensities. Rather counterintuitively, this reveals that the interconversion is inhibited with increasing pressure. Our results suggest that the spin conversion mechanism in methanol is via a quantum relaxation process with the quantum Zeno effect induced by molecular collisions. PMID:25880882

Kinetics and thermodynamics of the interchange of the morpheein forms of human porphobilinogen synthase.

PubMed

Selwood, Trevor; Tang, Lei; Lawrence, Sarah H; Anokhina, Yana; Jaffe, Eileen K

2008-03-11

A morpheein is a homo-oligomeric protein that can adopt different nonadditive quaternary assemblies (morpheein forms) with different functionalities. The human porphobilinogen synthase (PBGS) morpheein forms are a high activity octamer, a low activity hexamer, and two structurally distinct dimer conformations. Conversion between hexamer and octamer involves dissociation to dimers, conformational change at the dimer level, followed by association to the alternate assembly. The current work promotes an alternative and novel view of the physiologically relevant dimeric structures, which are derived from the crystal structures, but are distinct from the asymmetric units of their crystal forms. Using a well characterized heteromeric system (WT+F12L; Tang, L. et al. (2005) J. Biol. Chem. 280, 15786-15793), extensive study of the human PBGS morpheein reequilibration process now reveals that the intervening dimers do not dissociate to monomers. The morpheein equilibria of wild type (WT) human PBGS are found to respond to changes in pH, PBGS concentration, and substrate turnover. Notably, the WT enzyme is predominantly an octamer at neutral pH, but increasing pH results in substantial conversion to lower order oligomers. Most significantly, the free energy of activation for the conversion of WT+F12L human PBGS heterohexamers to hetero-octamers is determined to be the same as that for the catalytic conversion of substrate to product by the octamer, remarkably suggesting a common rate-limiting step for both processes, which is postulated to be the opening/closing of the active site lid.

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

Lutwack, R.

The goal of the Silicon Material Task, a part of the FSA Project, was to develop and demonstrate the technology for the low-cost production of silicon of suitable purity to be used as the basic material for the manufacture of terrestrial photovoltaic solar cells. To be compatible with the price goals of the FSA Project, the price of the produced silicon was to be less than $10/kg (in 1975 dollars). Summarized in this document are 11 different processes for the production of silicon that were investigated and developed to varying extent by industrial, university, and government researchers. The silane-production sectionmore » of the Union Carbide Corp. (UCC) silane process was developed completely in this program. Coupled with Siemens-type chemical vapor deposition reactors, the process was carried through the pilot plant stage. The overall UCC process involves the conversion of metallurgical-grade silicon to silane followed by decomposition of the silane to purified silicon. Production of very high-purity silane and silicon was demonstrated. Although it has as yet not achieved commercial application, the development of fluidized-bed technology for the low-cost, high-throughput conversion of silane-to-silicon has been demonstrated in the research laboratory and now is in engineering development.« less

Selective spatial attention modulates bottom-up informational masking of speech

PubMed Central

Carlile, Simon; Corkhill, Caitlin

2015-01-01

To hear out a conversation against other talkers listeners overcome energetic and informational masking. Largely attributed to top-down processes, information masking has also been demonstrated using unintelligible speech and amplitude-modulated maskers suggesting bottom-up processes. We examined the role of speech-like amplitude modulations in information masking using a spatial masking release paradigm. Separating a target talker from two masker talkers produced a 20 dB improvement in speech reception threshold; 40% of which was attributed to a release from informational masking. When across frequency temporal modulations in the masker talkers are decorrelated the speech is unintelligible, although the within frequency modulation characteristics remains identical. Used as a masker as above, the information masking accounted for 37% of the spatial unmasking seen with this masker. This unintelligible and highly differentiable masker is unlikely to involve top-down processes. These data provides strong evidence of bottom-up masking involving speech-like, within-frequency modulations and that this, presumably low level process, can be modulated by selective spatial attention. PMID:25727100

Selective spatial attention modulates bottom-up informational masking of speech.

PubMed

Carlile, Simon; Corkhill, Caitlin

2015-03-02

To hear out a conversation against other talkers listeners overcome energetic and informational masking. Largely attributed to top-down processes, information masking has also been demonstrated using unintelligible speech and amplitude-modulated maskers suggesting bottom-up processes. We examined the role of speech-like amplitude modulations in information masking using a spatial masking release paradigm. Separating a target talker from two masker talkers produced a 20 dB improvement in speech reception threshold; 40% of which was attributed to a release from informational masking. When across frequency temporal modulations in the masker talkers are decorrelated the speech is unintelligible, although the within frequency modulation characteristics remains identical. Used as a masker as above, the information masking accounted for 37% of the spatial unmasking seen with this masker. This unintelligible and highly differentiable masker is unlikely to involve top-down processes. These data provides strong evidence of bottom-up masking involving speech-like, within-frequency modulations and that this, presumably low level process, can be modulated by selective spatial attention.

Proteomics analysis of human placenta reveals glutathione metabolism dysfunction as the underlying pathogenesis for preeclampsia.

PubMed

Jin, Xiaohan; Xu, Zhongwei; Cao, Jin; Shao, Ping; Zhou, Maobin; Qin, Zhe; Liu, Yan; Yu, Fang; Zhou, Xin; Ji, Wenjie; Cai, Wei; Ma, Yongqiang; Wang, Chengyan; Shan, Nana; Yang, Ning; Chen, Xu; Li, Yuming

2017-09-01

Hypertensive disorder in pregnancy (HDP) refers to a series of diseases that cause the hypertension during pregnancy, including HDP, preeclampsia (PE) and eclampsia. This study screens differentially expressed proteins of placenta tissues in PE cases using 2D LC-MS/MS quantitative proteomics strategy. A total of 2281 proteins are quantified, of these, 145 altering expression proteins are successfully screened between PE and control cases (p<0.05). Bioinformatics analysis suggests that these proteins are mainly involved in many biological processes, such as oxidation reduction, mitochondrion organization, and acute inflammatory response. Especially, the glutamine metabolic process related molecules, GPX1, GPX3, SMS, GGCT, GSTK1, NFκB, GSTT2, SOD1 and GCLM, are involved in the switching process from oxidized glutathione (GSSG) conversion to the reduced glutathione (GSH) by glutathione, mercapturic acid and arginine metabolism process. Results of this study revealed that glutathione metabolism disorder of placenta tissues may contribute to the occurrence of PE disease. Copyright © 2017. Published by Elsevier B.V.

Impact of isovalent doping on radiation defects in silicon

NASA Astrophysics Data System (ADS)

Londos, C. A.; Sgourou, E. N.; Timerkaeva, D.; Chroneos, A.; Pochet, P.; Emtsev, V. V.

2013-09-01

Isovalent doping is an important process for the control of point defects in Si. Here, by means of infrared spectroscopy, we investigated the properties of the two main radiation-induced defects in Czochralski-Si (Cz-Si) the oxygen-vacancy (VO) and the carbon-oxygen (CiOi) centres. In particular, we investigated the effect of isovalent doping on the production, the thermal evolution, and the thermal stability of the VO and the CiOi defects. Additionally, we studied the reactions that participate upon annealing and the defects formed as a result of these reactions. Upon annealing VO is converted to VO2 defect although part of the CiOi is converted to CsO2i complexes. Thus, we studied the conversion ratios [VO2]/[VO] and [CsO2i]/[CiOi] with respect to the isovalent dopant. Additionally, the role of carbon in the above processes was discussed. A delay between the temperature characterizing the onset of the VO decay and the temperature characterizing the VO2 growth as well the further growth of VO2 after the complete disappearance of VO indicate that the VO to VO2 conversion is a complex phenomenon with many reaction processes involved. Differences exhibited between the effects of the various dopants on the properties of the two defects were highlighted. The results are discussed in view of density functional theory calculations involving the interaction of isovalent dopants with intrinsic defects, the oxygen and carbon impurities in Si.

Adiabatic burst evaporation from bicontinuous nanoporous membranes

PubMed Central

Ichilmann, Sachar; Rücker, Kerstin; Haase, Markus; Enke, Dirk

2015-01-01

Evaporation of volatile liquids from nanoporous media with bicontinuous morphology and pore diameters of a few 10 nm is an ubiquitous process. For example, such drying processes occur during syntheses of nanoporous materials by sol–gel chemistry or by spinodal decomposition in the presence of solvents as well as during solution impregnation of nanoporous hosts with functional guests. It is commonly assumed that drying is endothermic and driven by non-equilibrium partial pressures of the evaporating species in the gas phase. We show that nearly half of the liquid evaporates in an adiabatic mode involving burst-like liquid-to-gas conversions. During single adiabatic burst evaporation events liquid volumes of up to 107 μm3 are converted to gas. The adiabatic liquid-to-gas conversions occur if air invasion fronts get unstable because of the built-up of high capillary pressures. Adiabatic evaporation bursts propagate avalanche-like through the nanopore systems until the air invasion fronts have reached new stable configurations. Adiabatic cavitation bursts thus compete with Haines jumps involving air invasion front relaxation by local liquid flow without enhanced mass transport out of the nanoporous medium and prevail if the mean pore diameter is in the range of a few 10 nm. The results reported here may help optimize membrane preparation via solvent-based approaches, solution-loading of nanopore systems with guest materials as well as routine use of nanoporous membranes with bicontinuous morphology and may contribute to better understanding of adsorption/desorption processes in nanoporous media. PMID:25926406

All-Optical Control of Linear and Nonlinear Energy Transfer via the Zeno Effect

NASA Astrophysics Data System (ADS)

Guo, Xiang; Zou, Chang-Ling; Jiang, Liang; Tang, Hong X.

2018-05-01

Microresonator-based nonlinear processes are fundamental to applications including microcomb generation, parametric frequency conversion, and harmonics generation. While nonlinear processes involving either second- (χ(2 )) or third- (χ(3 )) order nonlinearity have been extensively studied, the interaction between these two basic nonlinear processes has seldom been reported. In this paper we demonstrate a coherent interplay between second- and third- order nonlinear processes. The parametric (χ(2 ) ) coupling to a lossy ancillary mode shortens the lifetime of the target photonic mode and suppresses its density of states, preventing the photon emissions into the target photonic mode via the Zeno effect. Such an effect is then used to control the stimulated four-wave mixing process and realize a suppression ratio of 34.5.

Approaching patient engagement in research: what do patients with cardiovascular disease think?

PubMed

Finney Rutten, Lila J; Morris, Megan A; Schrader, Lisa M; Manemann, Sheila M; Pathak, Jyotishman; Dimler, Robert; Roger, Veronique L

2015-01-01

Movement toward patient-centered health care must be supported by an evidence base informed by greater patient engagement in research. Efforts to better understand patients' interest in and perspectives on involvement in the research process are fundamental to supporting movement of research programs toward greater patient engagement. We describe preliminary efforts to engage members of a community group of patients living with heart disease to better understand their interest and perspectives on involvement in research. A semi-structured focus group guide was developed to probe willingness to participate in the following three phases of research: preparation, execution, and translation. The focus group discussion, and our summary of key messages gleaned from said discussion, was organized around the phases of research that patients may be involved in, with the goal of delineating degrees of interest expressed for engagement in each phase. Consistent with what is known from the literature, a clear preference for engagement during the preparation and translation phase of the research process emerged. This preliminary conversation will guide our ongoing research efforts toward greater inclusion of patients throughout the research process.

Interpersonal reactivity and the attribution of emotional reactions.

PubMed

Haas, Brian W; Anderson, Ian W; Filkowski, Megan M

2015-06-01

The ability to identify the cause of another person's emotional reaction is an important component associated with improved success of social relationships and survival. Although many studies have investigated the mechanisms involved in emotion recognition, very little is currently known regarding the processes involved during emotion attribution decisions. Research on complementary "emotion understanding" mechanisms, including empathy and theory of mind, has demonstrated that emotion understanding decisions are often made through relatively emotion- or cognitive-based processing streams. The current study was designed to investigate the behavioral and brain mechanisms involved in emotion attribution decisions. We predicted that dual processes, emotional and cognitive, are engaged during emotion attribution decisions. Sixteen healthy adults completed the Interpersonal Reactivity Index to characterize individual differences in tendency to make emotion- versus cognitive-based interpersonal decisions. Participants then underwent functional MRI while making emotion attribution decisions. We found neuroimaging evidence that emotion attribution decisions engage a similar brain network as other forms of emotion understanding. Further, we found evidence in support of a dual processes model involved during emotion attribution decisions. Higher scores of personal distress were associated with quicker emotion attribution decisions and increased anterior insula activity. Conversely, higher scores in perspective taking were associated with delayed emotion attribution decisions and increased prefrontal cortex and premotor activity. These findings indicate that the making of emotion attribution decisions relies on dissociable emotional and cognitive processing streams within the brain. (c) 2015 APA, all rights reserved).

Revisiting the diffusion approximation to estimate evolutionary rates of gene family diversification.

PubMed

Gjini, Erida; Haydon, Daniel T; David Barry, J; Cobbold, Christina A

2014-01-21

Genetic diversity in multigene families is shaped by multiple processes, including gene conversion and point mutation. Because multi-gene families are involved in crucial traits of organisms, quantifying the rates of their genetic diversification is important. With increasing availability of genomic data, there is a growing need for quantitative approaches that integrate the molecular evolution of gene families with their higher-scale function. In this study, we integrate a stochastic simulation framework with population genetics theory, namely the diffusion approximation, to investigate the dynamics of genetic diversification in a gene family. Duplicated genes can diverge and encode new functions as a result of point mutation, and become more similar through gene conversion. To model the evolution of pairwise identity in a multigene family, we first consider all conversion and mutation events in a discrete manner, keeping track of their details and times of occurrence; second we consider only the infinitesimal effect of these processes on pairwise identity accounting for random sampling of genes and positions. The purely stochastic approach is closer to biological reality and is based on many explicit parameters, such as conversion tract length and family size, but is more challenging analytically. The population genetics approach is an approximation accounting implicitly for point mutation and gene conversion, only in terms of per-site average probabilities. Comparison of these two approaches across a range of parameter combinations reveals that they are not entirely equivalent, but that for certain relevant regimes they do match. As an application of this modelling framework, we consider the distribution of nucleotide identity among VSG genes of African trypanosomes, representing the most prominent example of a multi-gene family mediating parasite antigenic variation and within-host immune evasion. © 2013 Published by Elsevier Ltd. All rights reserved.

A Commercialization Roadmap for Carbon-Negative Energy Systems

NASA Astrophysics Data System (ADS)

Sanchez, D.

2016-12-01

The Intergovernmental Panel on Climate Change (IPCC) envisages the need for large-scale deployment of net-negative CO2 emissions technologies by mid-century to meet stringent climate mitigation goals and yield a net drawdown of atmospheric carbon. Yet there are few commercial deployments of BECCS outside of niche markets, creating uncertainty about commercialization pathways and sustainability impacts at scale. This uncertainty is exacerbated by the absence of a strong policy framework, such as high carbon prices and research coordination. Here, we propose a strategy for the potential commercial deployment of BECCS. This roadmap proceeds via three steps: 1) via capture and utilization of biogenic CO2 from existing bioenergy facilities, notably ethanol fermentation, 2) via thermochemical co-conversion of biomass and fossil fuels, particularly coal, and 3) via dedicated, large-scale BECCS. Although biochemical conversion is a proven first market for BECCS, this trajectory alone is unlikely to drive commercialization of BECCS at the gigatonne scale. In contrast to biochemical conversion, thermochemical conversion of coal and biomass enables large-scale production of fuels and electricity with a wide range of carbon intensities, process efficiencies and process scales. Aside from systems integration, primarily technical barriers are involved in large-scale biomass logistics, gasification and gas cleaning. Key uncertainties around large-scale BECCS deployment are not limited to commercialization pathways; rather, they include physical constraints on biomass cultivation or CO2 storage, as well as social barriers, including public acceptance of new technologies and conceptions of renewable and fossil energy, which co-conversion systems confound. Despite sustainability risks, this commercialization strategy presents a pathway where energy suppliers, manufacturers and governments could transition from laggards to leaders in climate change mitigation efforts.

Microchemical Systems for Fuel Processing and Conversion to Electrical Power

DTIC Science & Technology

2007-03-15

Processing and Conversion to Electrical Power - Final Report 2 Table of Contents Table of Contents... Processing and Conversion to Electrical Power - Final Report 3 8.7 Development of Large Free-Standing Electrolyte-supported Micro Fuel Cell Membranes...84 MURI Microchemical Systems for Fuel Processing and

Participant characteristics and observed support in conversations involving people with communication disorders.

PubMed

Eriksson, Karin; Hartelius, Lena; Saldert, Charlotta

2016-10-01

Communication partner training is an increasingly common approach to improve the possibilities for people with communication disorders to participate in everyday interaction. So far, though, little is known about what conversation partner characteristics might influence the ability to be a supportive partner in conversation. The current study explored possible associations between the observed skill to support a person with communication difficulties in conversation and the following characteristics of the conversation partner; executive function, inference ability, age, education level and relationship to the person with communication disorder. The impact of the aetiology of the communication difficulties was also explored. Thirty-five dyads participated: 23 people with aphasia along with 18 significant others and five enrolled nurses and 12 people with Parkinson's disease along with 10 significant others and two enrolled nurses. Only tendencies of associations were found between observed skill to support conversation and executive function for the significant others and inference ability for the enrolled nurses. Although type of activity involved in the conversation may be a key factor, the results indicate that executive function and ability to make mental inferences may matter for the ability to support a person with communication disorder in conversation.

(Bio)Chemical Tailoring of Biogenic 3-D Nanopatterned Templates with Energy-Relevant Functionalities

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

Sandhage, Kenneth H; Kroger, Nils

2014-09-08

The overall aim of this research has been to obtain fundamental understanding of (bio)chemical methodologies that will enable utilization of the unique 3-D nanopatterned architectures naturally produced by diatoms for the syntheses of advanced functional materials attractive for applications in energy harvesting/conversion and storage. This research has been conducted in three thrusts: Thrust 1 (In vivo immobilization of proteins in diatom biosilica) is directed towards elucidating the fundamental mechanism(s) underlying the cellular processes of in vivo immobilization of proteins in diatom silica. Thrust 2 (Shape-preserving reactive conversion of diatom biosilica into porous, high-surface area inorganic replicas) is aimed at understandingmore » the fundamental mechanisms of shape preservation and nanostructural evolution associated with the reactive conversion and/or coating-based conversion of diatom biosilica templates into porous inorganic replicas. Thrust 3 (Immobilization of energy-relevant enzymes in diatom biosilica and onto diatom biosilica-derived inorganic replicas) involves use of the results from both Thrust 1 and 2 to develop strategies for in vivo and in vitro immobilization of enzymes in/on diatom biosilica and diatom biosilica-derived inorganic replicas, respectively. This Final Report describes progress achieved in all 3 of these thrusts.« less

Two-Particle Interference of Electron Pairs on a Molecular Level

DOE PAGES

Waitz, M.; Metz, D.; Lower, J.; ...

2016-08-15

Here, wWe investigate the photodouble ionization of H 2 molecules with 400 eV photons. We find that the emitted electrons do not show any sign of two-center interference fringes in their angular emission distributions if considered separately. Conversely, the quasiparticle consisting of both electrons (i.e., the "dielectron") does. The work highlights the fact that nonlocal effects are embedded everywhere in nature where many-particle processes are involved.

Hydrogenolysis Of 5-Carbon Sugars, Sugar Alcohols And Compositions For Reactions Involving Hydrogen

DOEpatents

Werpy, Todd A.; Frye, Jr., John G.; Zacher, Alan H.; Miller, Dennis J.

2004-01-13

Methods and compositions for reactions of hydrogen over a Re-containing catalyst with compositions containing a 5-carbon sugar, sugar alcohol, or lactic acid are described. It has been surprisingly discovered that reaction with hydrogen over a Re-containing multimetallic catalyst resulted in superior conversion and selectivity to desired products such as propylene glycol. A process for the synthesis of PG from lactate or lactic acid is also described.

Molecular diodes in optical rectennas

NASA Astrophysics Data System (ADS)

Duché, David; Palanchoke, Ujwol; Terracciano, Luigi; Dang, Florian-Xuan; Patrone, Lionel; Le Rouzo, Judikael; Balaban, Téodore Silviu; Alfonso, Claude; Charai, Ahmed; Margeat, Olivier; Ackermann, Jorg; Gourgon, Cécile; Simon, Jean-Jacques; Escoubas, Ludovic

2016-09-01

The photo conversion efficiencies of the 1st and 2nd generat ion photovoltaic solar cells are limited by the physical phenomena involved during the photo-conversion processes. An upper limit around 30% has been predicted for a monojunction silicon solar cell. In this work, we study 3rd generation solar cells named rectenna which could direct ly convert visible and infrared light into DC current. The rectenna technology is at odds with the actual photovoltaic technologies, since it is not based on the use of semi-conducting materials. We study a rectenna architecture consist ing of plasmonic nano-antennas associated with rectifying self assembled molecular diodes. We first opt imized the geometry of plasmonic nano-antennas using an FDTD method. The optimal antennas are then realized using a nano-imprint process and associated with self assembled molecular diodes in 11- ferrocenyl-undecanethiol. Finally, The I(V) characterist ics in darkness of the rectennas has been carried out using an STM. The molecular diodes exhibit averaged rect ification ratios of 5.

Strategies for Efficient Charge Separation and Transfer in Artificial Photosynthesis of Solar Fuels.

PubMed

Xu, Yuxing; Li, Ailong; Yao, Tingting; Ma, Changtong; Zhang, Xianwen; Shah, Jafar Hussain; Han, Hongxian

2017-11-23

Converting sunlight to solar fuels by artificial photosynthesis is an innovative science and technology for renewable energy. Light harvesting, photogenerated charge separation and transfer (CST), and catalytic reactions are the three primary steps in the processes involved in the conversion of solar energy to chemical energy (SE-CE). Among the processes, CST is the key "energy pump and delivery" step in determining the overall solar-energy conversion efficiency. Efficient CST is always high priority in designing and assembling artificial photosynthesis systems for solar-fuel production. This Review not only introduces the fundamental strategies for CST but also the combinatory application of these strategies to five types of the most-investigated semiconductor-based artificial photosynthesis systems: particulate, Z-scheme, hybrid, photoelectrochemical, and photovoltaics-assisted systems. We show that artificial photosynthesis systems with high SE-CE efficiency can be rationally designed and constructed through combinatory application of these strategies, setting a promising blueprint for the future of solar fuels. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Potential useful products from solid wastes.

PubMed

Golueke, C G; Diaz, L F

1991-10-01

Wastes have been aptly defined as "items, i.e. resources, that have been discarded because their possessors no longer have an apparent use for them". Accordingly, "wastes" have a significance only in relation to the items and those who have discarded them. The discarded items now are resources awaiting reclamation. Reclamation usually involves either salvage or conversion--or in modern terminology, "reuse" or "recycling". Reclamation for reuse consists in refurbishing or other upgrading without significantly altering original form and composition. Examples of wastes amenable to reuse are containers (bottles, etc.), cartons and repairable tires. With "recycling" (i.e. conservation), the discarded items are processed such that they become raw material, i.e. resources in the manufacture of "new" products. The variety of processes is wide, ranging from simply physical (grinding) through thermal (melting, gasification, combustion), to biological (composting, biogasification, hydrolysis, microbial protein production). In the paper, reuse and recycling (conversion) are evaluated in terms of advantages and disadvantages (limitations) and their respective technologies are described and discussed in detail.

Halogen-Mediated Conversion of Hydrocarbons to Commodities.

PubMed

Lin, Ronghe; Amrute, Amol P; Pérez-Ramírez, Javier

2017-03-08

Halogen chemistry plays a central role in the industrial manufacture of various important chemicals, pharmaceuticals, and polymers. It involves the reaction of halogens or halides with hydrocarbons, leading to intermediate compounds which are readily converted to valuable commodities. These transformations, predominantly mediated by heterogeneous catalysts, have long been successfully applied in the production of polymers. Recent discoveries of abundant conventional and unconventional natural gas reserves have revitalized strong interest in these processes as the most cost-effective gas-to-liquid technologies. This review provides an in-depth analysis of the fundamental understanding and applied relevance of halogen chemistry in polymer industries (polyvinyl chloride, polyurethanes, and polycarbonates) and in the activation of light hydrocarbons. The reactions of particular interest include halogenation and oxyhalogenation of alkanes and alkenes, dehydrogenation of alkanes, conversion of alkyl halides, and oxidation of hydrogen halides, with emphasis on the catalyst, reactor, and process design. Perspectives on the challenges and directions for future development in this exciting field are provided.

Complexity in modeling of residual stresses and strains during polymerization of bone cement: effects of conversion, constraint, heat transfer, and viscoelastic property changes.

PubMed

Gilbert, Jeremy L

2006-12-15

Aseptic loosening of cemented joint prostheses remains a significant concern in orthopedic biomaterials. One possible contributor to cement loosening is the development of porosity, residual stresses, and local fracture of the cement that may arise from the in-situ polymerization of the cement. In-situ polymerization of acrylic bone cement is a complex set of interacting processes that involve polymerization reactions, heat generation and transfer, full or partial mechanical constraint, evolution of conversion- and temperature-dependent viscoelastic material properties, and thermal and conversion-driven changes in the density of the cement. Interactions between heat transfer and polymerization can lead to polymerization fronts moving through the material. Density changes during polymerization can, in the presence of mechanical constraint, lead to the development of locally high residual strain energy and residual stresses. This study models the interactions during bone cement polymerization and determines how residual stresses develop in cement and incorporates temperature and conversion-dependent viscoelastic behavior. The results show that the presence of polymerization fronts in bone cement result in locally high residual strain energies. A novel heredity integral approach is presented to track residual stresses incorporating conversion and temperature dependent material property changes. Finally, the relative contribution of thermal- and conversion-dependent strains to residual stresses is evaluated and it is found that the conversion-based strains are the major contributor to the overall behavior. This framework provides the basis for understanding the complex development of residual stresses and can be used as the basis for developing more complex models of cement behavior.

Green acetylation of solketal and glycerol formal by heterogeneous acid catalysts to form a biodiesel fuel additive.

PubMed

Dodson, Jennifer R; Leite, Thays d C M; Pontes, Nathália S; Peres Pinto, Bianca; Mota, Claudio J A

2014-09-01

A glut of glycerol has formed from the increased production of biodiesel, with the potential to integrate the supply chain by using glycerol additives to improve biodiesel properties. Acetylated acetals show interesting cold flow and viscosity effects. Herein, a solventless heterogeneously catalyzed process for the acetylation of both solketal and glycerol formal to new products is demonstrated. The process is optimized by studying the effect of acetylating reagent (acetic acid and acetic anhydride), reagent molar ratios, and a variety of commercial solid acid catalysts (Amberlyst-15, zeolite Beta, K-10 Montmorillonite, and niobium phosphate) on the conversion and selectivities. High conversions (72-95%) and selectivities (86-99%) to the desired products results from using acetic anhydride as the acetylation reagent and a 1:1 molar ratio with all catalysts. Overall, there is a complex interplay between the solid catalyst, reagent ratio, and acetylating agent on the conversion, selectivities, and byproducts formed. The variations are discussed and explained in terms of reactivity, thermodynamics, and reaction mechanisms. An alternative and efficient approach to the formation of 100% triacetin involves the ring-opening, acid-catalyzed acetylation from solketal or glycerol formal with excesses of acetic anhydride. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Snowden-Swan, Lesley J.; Spies, Kurt A.; Lee, Guo-Shuh J.

Bio-oil from fast pyrolysis of biomass requires multi-stage catalytic hydroprocessing to produce hydrocarbon drop-in fuels. The current proposed process design involves fixed beds of ruthenium-based catalyst and conventional petroleum hydrotreating catalyst. Similar to petroleum processing, the catalyst is spent as a result of coking and other deactivation mechanisms, and must be changed out periodically. Biofuel life cycle greenhouse gas (GHG) assessments typically ignore the impact of catalyst consumed during fuel conversion as a result of limited lifetime, representing a data gap in the analyses. To help fill this data gap, life cycle GHGs were estimated for two representative examples ofmore » fast pyrolysis bio-oil hydrotreating catalyst, NiMo/Al2O3 and Ru/C, and integrated into the conversion-stage GHG analysis. Life cycle GHGs for the NiMo/Al2O3 and Ru/C catalysts are estimated at 5.5 and 81 kg CO2-e/kg catalyst, respectively. Contribution of catalyst consumption to total conversion-stage GHGs is 0.5% for NiMo/Al2O3 and 5% for Ru/C. This analysis does not consider secondary sourcing of metals for catalyst manufacture and therefore these are likely to be conservative estimates compared to applications where a spent catalyst recycler can be used.« less

Bacterial species involved in the conversion of dietary flavonoids in the human gut.

PubMed

Braune, Annett; Blaut, Michael

2016-05-03

The gut microbiota plays a crucial role in the conversion of dietary flavonoids and thereby affects their health-promoting effects in the human host. The identification of the bacteria involved in intestinal flavonoid conversion has gained increasing interest. This review summarizes available information on the so far identified human intestinal flavonoid-converting bacterial species and strains as well as their enzymes catalyzing the underlying reactions. The majority of described species involved in flavonoid transformation are capable of carrying out the O-deglycosylation of flavonoids. Other bacteria cleave the less common flavonoid-C-glucosides and/or further degrade the aglycones of flavonols, flavanonols, flavones, flavanones, dihydrochalcones, isoflavones and monomeric flavan-3-ols. To increase the currently limited knowledge in this field, identification of flavonoid-converting bacteria should be continued using culture-dependent screening or isolation procedures and molecular approaches based on sequence information of the involved enzymes.

The methodology of variable management of propellant fuel consumption by jet-propulsion engines of a spacecraft

NASA Astrophysics Data System (ADS)

Kovtun, V. S.

2012-12-01

Traditionally, management of propellant fuel consumption on board of a spacecraft is only associated with the operation of jet-propulsion engines (JPE) that are actuator devices of motion control systems (MCS). The efficiency of propellant fuel consumption depends not only on the operation of the MCS, but also, to one extent or another, on all systems functioning on board of a spacecraft, and on processes that occur in them and involve conversion of variable management of propellant fuel consumption by JPEs as a constituent part of the control of the complex process of spacecraft flight.

Responding to Student Essays: A Conversation.

ERIC Educational Resources Information Center

Teichmann, Sandra Gail; Fike, Darrell

Two college writing teachers share their viewpoint that people outside the academic setting often misunderstand the time-consuming activities involved with responding to student writing. They agree that teachers should envision evaluation as conducting a conversation with the writer of the essay. The key component of this conversation, depending…

Synergic solventing-out crystallization with subsequent time-delay thermal annealing of PbI2 precursor in mesostructured perovskite solar cells

NASA Astrophysics Data System (ADS)

Jia, Fujin; Guo, Yanqun; Che, Lijia; Liu, Zhiyong; Zeng, Zhigang; Cai, Chuanbing

2018-06-01

Although the two-step sequential deposition method provides an efficient route to fabricate high performance perovskite solar cells (PSSCs) with increasing reproducibility, the inefficient and incomplete conversion of PbI2 to perovskite is still quite a challenge. Following pioneering works, we found that the conversion process from PbI2 to perovskite mainly involves diffusion, infiltration, contact and reaction. In order to facilitate the conversion from PbI2 to perovskite, we demonstrate an effective method to regulate supersaturation level (the driving force to crystallization) of PbI2 by solventing-out crystallization combining with subsequent time-delay thermal annealing of PbI2 wet film. Enough voids and spaces in resulting porous PbI2 layer will be in favor of efficient diffusion, infiltration of CH3NH3I solution, and further enhance the contact and reaction between PbI2 and CH3NH3I in the whole film, leading to rapid, efficient and complete perovskite conversion with a conversion level of about 99.9%. Enhancement of light harvesting ranging from visible to near-IR region was achieved for the resultant high-quality perovskite. Upon this combined method, the fabricated mesostructured solar cells show tremendous power conversion efficiency (PCE) improvement from 3.2% to about 12.3% with less hysteresis owing to the simultaneous enhancement of short-circuit photocurrent density (J sc), open-circuit voltage (V oc) and fill factor (FF).

Diversified Structural Basis of a Conserved Molecular Mechanism for pH-Dependent Dimerization in Spider Silk N-Terminal Domains.

PubMed

Otikovs, Martins; Chen, Gefei; Nordling, Kerstin; Landreh, Michael; Meng, Qing; Jörnvall, Hans; Kronqvist, Nina; Rising, Anna; Johansson, Jan; Jaudzems, Kristaps

2015-08-17

Conversion of spider silk proteins from soluble dope to insoluble fibers involves pH-dependent dimerization of the N-terminal domain (NT). This conversion is tightly regulated to prevent premature precipitation and enable rapid silk formation at the end of the duct. Three glutamic acid residues that mediate this process in the NT from Euprosthenops australis major ampullate spidroin 1 are well conserved among spidroins. However, NTs of minor ampullate spidroins from several species, including Araneus ventricosus ((Av)MiSp NT), lack one of the glutamic acids. Here we investigate the pH-dependent structural changes of (Av)MiSp NT, revealing that it uses the same mechanism but involves a non-conserved glutamic acid residue instead. Homology modeling of the structures of other MiSp NTs suggests that these harbor different compensatory residues. This indicates that, despite sequence variations, the molecular mechanism underlying pH-dependent dimerization of NT is conserved among different silk types. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cleave and couple: toward fully sustainable catalytic conversion of lignocellulose to value added building blocks and fuels.

PubMed

Sun, Zhuohua; Barta, Katalin

2018-06-21

The structural complexity of lignocellulose offers unique opportunities for the development of entirely new, energy efficient and waste-free pathways in order to obtain valuable bio-based building blocks. Such sustainable catalytic methods - specifically tailored to address the efficient conversion of abundant renewable starting materials - are necessary to successfully compete, in the future, with fossil-based multi-step processes. In this contribution we give a summary of recent developments in this field and describe our "cleave and couple" strategy, where "cleave" refers to the catalytic deconstruction of lignocellulose to aromatic and aliphatic alcohol intermediates, and "couple" involves the development of novel, sustainable transformations for the formation of C-C and C-N bonds in order to obtain a range of attractive products from lignocellulose.

Homogeneously catalysed conversion of aqueous formaldehyde to H2 and carbonate.

PubMed

Trincado, M; Sinha, Vivek; Rodriguez-Lugo, Rafael E; Pribanic, Bruno; de Bruin, Bas; Grützmacher, Hansjörg

2017-04-28

Small organic molecules provide a promising solution for the requirement to store large amounts of hydrogen in a future hydrogen-based energy system. Herein, we report that diolefin-ruthenium complexes containing the chemically and redox non-innocent ligand trop 2 dad catalyse the production of H 2 from formaldehyde and water in the presence of a base. The process involves the catalytic conversion to carbonate salt using aqueous solutions and is the fastest reported for acceptorless formalin dehydrogenation to date. A mechanism supported by density functional theory calculations postulates protonation of a ruthenium hydride to form a low-valent active species, the reversible uptake of dihydrogen by the ligand and active participation of both the ligand and the metal in substrate activation and dihydrogen bond formation.

The morphing of geographical features by Fourier transformation.

PubMed

Li, Jingzhong; Liu, Pengcheng; Yu, Wenhao; Cheng, Xiaoqiang

2018-01-01

This paper presents a morphing model of vector geographical data based on Fourier transformation. This model involves three main steps. They are conversion from vector data to Fourier series, generation of intermediate function by combination of the two Fourier series concerning a large scale and a small scale, and reverse conversion from combination function to vector data. By mirror processing, the model can also be used for morphing of linear features. Experimental results show that this method is sensitive to scale variations and it can be used for vector map features' continuous scale transformation. The efficiency of this model is linearly related to the point number of shape boundary and the interceptive value n of Fourier expansion. The effect of morphing by Fourier transformation is plausible and the efficiency of the algorithm is acceptable.

Accelerating Commercialization of Algal Biofuels Through Partnerships (Brochure)

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

Not Available

2011-10-01

This brochure describes National Renewable Energy Laboratory's (NREL's) algal biofuels research capabilities and partnership opportunities. NREL is accelerating algal biofuels commercialization through: (1) Advances in applied biology; (2) Algal strain development; (3) Development of fuel conversion pathways; (4) Techno-economic analysis; and (5) Development of high-throughput lipid analysis methodologies. NREL scientists and engineers are addressing challenges across the algal biofuels value chain, including algal biology, cultivation, harvesting and extraction, and fuel conversion. Through partnerships, NREL can share knowledge and capabilities in the following areas: (1) Algal Biology - A fundamental understanding of algal biology is key to developing cost-effective algal biofuelsmore » processes. NREL scientists are experts in the isolation and characterization of microalgal species. They are identifying genes and pathways involved in biofuel production. In addition, they have developed a high-throughput, non-destructive technique for assessing lipid production in microalgae. (2) Cultivation - NREL researchers study algal growth capabilities and perform compositional analysis of algal biomass. Laboratory-scale photobioreactors and 1-m2 open raceway ponds in an on-site greenhouse allow for year-round cultivation of algae under a variety of conditions. A bioenergy-focused algal strain collection is being established at NREL, and our laboratory houses a cryopreservation system for long-term maintenance of algal cultures and preservation of intellectual property. (3) Harvesting and Extraction - NREL is investigating cost-effective harvesting and extraction methods suitable for a variety of species and conditions. Areas of expertise include cell wall analysis and deconstruction and identification and utilization of co-products. (4) Fuel Conversion - NREL's excellent capabilities and facilities for biochemical and thermochemical conversion of biomass to biofuels are being applied to algal biofuels processes. Analysts are also testing algal fuel properties to measure energy content and ensure compatibility with existing fueling infrastructure. (5) Cross-Cutting Analysis - NREL scientists and engineers are conducting rigorous techno-economic analyses of algal biofuels processes. In addition, they are performing a full life cycle assessment of the entire algae-to-biofuels process.« less

The "Alfvén" proposal for the European Space Agency M5 Mission Call

NASA Astrophysics Data System (ADS)

Berthomier, M.; Fazakerley, A. N.

2017-12-01

The Alfvén mission objective is to elucidate the particle acceleration processes and their consequences for electromagnetic radiation and energy transport in strongly magnetised plasmas. The Earth's Auroral Acceleration Region is a unique laboratory for investigating these processes. The only way to distinguish between the models describing acceleration processes at the heart of Magnetosphere-Ionosphere Coupling is to combine high-time resolution in situ measurements (as pioneered by FAST), multi-point measurements (as pioneered by CLUSTER), and auroral arc imaging in one mission. Charged particle acceleration in strongly magnetized plasmas requires the conversion of electromagnetic energy into magnetic-field-aligned particle kinetic energy. Alfvén will measure for the first time the occurrence and distribution of small scale parallel electric fields in space and time. In order to determine the relative efficiency of the different conversion mechanisms, Alfvén will also measure the corresponding particle energy fluxes locally and into the aurora. Alfvén will discover how electromagnetic radiation is generated in the acceleration region and how it escapes. Alfvén will make key measurements of Auroral Kilometric Radiation needed to test competing models of wave generation, mode conversion and escape from their source region. These will reveal the mode conversion processes and which information is ultimately carried by the polarization of radio waves reaching free space. Alfvén will discover the global impact of particle acceleration on the dynamic coupling between a magnetized object and its plasma environment. Dual spacecraft measurements offer the unique opportunity to unambiguously determine which part of the energy flowing into the ionosphere is eventually dissipated in this collisional plasma and which part is transmitted to outflowing ions of ionospheric origin. The Alfvén mission design involves use of two simple identical spacecraft, a comprehensive suite of inter-calibrated particles and fields instruments, cutting edge auroral imaging, easily accessible orbits that frequently visit the region of scientific interest and straightforward operations.

Thermochemical Conversion Techno-Economic Analysis | Bioenergy | NREL

Science.gov Websites

Conversion Techno-Economic Analysis Thermochemical Conversion Techno-Economic Analysis NREL's Thermochemical Conversion Analysis team focuses on the conceptual process design and techno-economic analysis , detailed process models, and TEA developed under this project provide insights into the potential economic

Alkali Potassium Induced HCl/CO2 Selectivity Enhancement and Chlorination Reaction Inhibition for Catalytic Oxidation of Chloroaromatics.

PubMed

Sun, Pengfei; Wang, Wanglong; Weng, Xiaole; Dai, Xiaoxia; Wu, Zhongbiao

2018-06-05

Industrial combustion of chloroaromatics is likely to generate unintentional biphenyls (PCBs), polychlorinated dibenzo- p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). This process involves a surface-mediated reaction and can be accelerated in the presence of a catalyst. In the past decade, the effect of surface nature of applied catalysts on the conversion of chloroaromatics to PCBs/PCDD/PCDF has been well explored. However, studies on how the flue gas interferent components affect such a conversion process remain insufficient. In this article, a critical flue gas interferent component, alkali potassium, was investigated to reveal its effect on the chloroaromatics oxidation at a typical solid acid-base catalyst, Mn x Ce 1- x O 2 /HZSM-5. The loading of alkali potassium was found to improve the Lewis acidity of the catalyst (by increasing the amounts of surface Mn 4+ after calcination), which thus promoted the CO 2 selectivity for catalytic chlorobenzene (CB) oxidation. The KOH with a high hydrophilicity has favored the adsorption/activation of H 2 O molecules that provided sufficient hydroxyl groups and possibly induced a hydrolysis process to promote the formation of HCl. The K ion also served as a potential sink for chorine ions immobilization (via forming KCl). Both of these inhibited the formation of phenyl polychloride byproducts, thereby blocking the conversion of CB to chlorophenol and then PCDDs/PCDFs, and potentially ensuring a durable operation and less secondary pollution for the catalytic chloroaromatics combustion in industry.

Plasma catalytic reforming of methane

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

Bromberg, L.; Cohn, D.R.; Rabinovich, A.

1998-08-01

Thermal plasma technology can be efficiently used in the production of hydrogen and hydrogen-rich gases from methane and a variety of fuels. This paper describes progress in plasma reforming experiments and calculations of high temperature conversion of methane using heterogeneous processes. The thermal plasma is a highly energetic state of matter that is characterized by extremely high temperatures (several thousand degrees Celsius) and high degree of dissociation and substantial degree of ionization. The high temperatures accelerate the reactions involved in the reforming process. Hydrogen-rich gas (50% H{sub 2}, 17% CO and 33% N{sub 2}, for partial oxidation/water shifting) can bemore » efficiently made in compact plasma reformers. Experiments have been carried out in a small device (2--3 kW) and without the use of efficient heat regeneration. For partial oxidation/water shifting, it was determined that the specific energy consumption in the plasma reforming processes is 16 MJ/kg H{sub 2} with high conversion efficiencies. Larger plasmatrons, better reactor thermal insulation, efficient heat regeneration and improved plasma catalysis could also play a major role in specific energy consumption reduction and increasing the methane conversion. A system has been demonstrated for hydrogen production with low CO content ({approximately} 1.5%) with power densities of {approximately} 30 kW (H{sub 2} HHV)/liter of reactor, or {approximately} 10 m{sup 3}/hr H{sub 2} per liter of reactor. Power density should further increase with increased power and improved design.« less

Vertical datum conversion process for the inland and coastal gage network located in the New England, Mid-Atlantic, and South Atlantic-Gulf hydrologic regions

USGS Publications Warehouse

Rydlund, Jr., Paul H.; Noll, Michael L.

2017-03-07

Datum conversions from the National Geodetic Vertical Datum of 1929 to the North American Vertical Datum of 1988 among inland and coastal gages throughout the hydrologic regions of New England, the Mid-Atlantic, and the South Atlantic-Gulf have implications among river and storm surge forecasting, general commerce, and water-control operations. The process of data conversions may involve the application of a recovered National Geodetic Vertical Datum of 1929–North American Vertical Datum of 1988 offset, a simplistic datum transformation using VDatum or VERTCON software, or a survey, depending on a gaging network datum evaluation, anticipated uncertainties for data use among the cooperative water community, and methods used to derive the conversion. Datum transformations from National Geodetic Vertical Datum of 1929 to North American Vertical Datum of 1988 using VERTCON purport errors of ± 0.13 foot at the 95 percent confidence level among modeled points, claiming more consistency along the east coast. Survey methods involving differential and trigonometric leveling, along with observations using Global Navigation Satellite System technology, afford a variety of approaches to establish or perpetuate a datum during a survey. Uncertainties among leveling approaches are generally < 0.1 foot, and and Global Navigation Satellite System approaches may be categorized with uncertainties of ≤0.1 foot for a Level I quality category and ≥0.1 foot for Level II or III quality categories (defined by the U.S. Geological Survey) by observation and review of experienced practice. The conversion process is initiated with an evaluation of the inland and coastal gage network datum, beginning with altitude datum components and the history of those components queried through the U.S. Geological Survey Groundwater Site Inventory database. Subsequent edits to the Groundwater Site Inventory database may be required and a consensus reached among the U.S. Geological Survey Water Science Centers to identify the outstanding workload categorized as in-office datum transformations or offset applications versus out-of-office survey efforts. Datum conversions or datum establishment for the inland or coastal gaging network should meet datum uncertainty requirements among other Federal agencies. Datum uncertainty requirements are ±0.25 foot for U.S. Army Corps of Engineers water-control or construction projects and ±0.16 foot for Federal Emergency Management Agency field surveys and checkpoint surveys used for mapping. River level forecasts generally are defined as ± 0.10 foot among the National Oceanic and Atmospheric Administration–National Weather Service. Collaboration and communication among the cooperative water community is necessary during a datum conversion or datum change. Datum notification time-change requirements set by the National Oceanic and Atmospheric Administration–National Weather Service vary from 30 to 120 days, depending on datum conversion or datum-change case scenarios. Notification times associated with these case scenarios may be useful to the National Oceanic and Atmospheric Administration–National Weather Service and U.S. Army Corps of Engineers, because their daily operations are time sensitive, unlike the notification time change requirements of other entities that make up the cooperative water community. At the time of this writing, a future geopotential datum resulting from Gravity for the Redefinition of the American Vertical Datum is anticipated in 2022. A future version of VDatum and VERTCON is anticipated to provide a transformation among North American Vertical Datum of 1988 elevations to the new geopotential datum.

Comparative genome analysis of the candidate functional starter culture strains Lactobacillus fermentum 222 and Lactobacillus plantarum 80 for controlled cocoa bean fermentation processes.

PubMed

Illeghems, Koen; De Vuyst, Luc; Weckx, Stefan

2015-10-12

Lactobacillus fermentum 222 and Lactobacillus plantarum 80, isolates from a spontaneous Ghanaian cocoa bean fermentation process, proved to be interesting functional starter culture strains for cocoa bean fermentations. Lactobacillus fermentum 222 is a thermotolerant strain, able to dominate the fermentation process, thereby converting citrate and producing mannitol. Lactobacillus plantarum 80 is an acid-tolerant and facultative heterofermentative strain that is competitive during cocoa bean fermentation processes. In this study, whole-genome sequencing and comparative genome analysis was used to investigate the mechanisms of these strains to dominate the cocoa bean fermentation process. Through functional annotation and analysis of the high-coverage contigs obtained through 454 pyrosequencing, plantaricin production was predicted for L. plantarum 80. For L. fermentum 222, genes encoding a complete arginine deiminase pathway were attributed. Further, in-depth functional analysis revealed the capacities of these strains associated with carbohydrate and amino acid metabolism, such as the ability to use alternative external electron acceptors, the presence of an extended pyruvate metabolism, and the occurrence of several amino acid conversion pathways. A comparative genome sequence analysis using publicly available genome sequences of strains of the species L. plantarum and L. fermentum revealed unique features of both strains studied. Indeed, L. fermentum 222 possessed genes encoding additional citrate transporters and enzymes involved in amino acid conversions, whereas L. plantarum 80 is the only member of this species that harboured a gene cluster involved in uptake and consumption of fructose and/or sorbose. In-depth genome sequence analysis of the candidate functional starter culture strains L. fermentum 222 and L. plantarum 80 revealed their metabolic capacities, niche adaptations and functionalities that enable them to dominate the cocoa bean fermentation process. Further, these results offered insights into the cocoa bean fermentation ecosystem as a whole and will facilitate the selection of appropriate starter culture strains for controlled cocoa bean fermentation processes.

Application of multi response optimization with grey relational analysis and fuzzy logic method

NASA Astrophysics Data System (ADS)

Winarni, Sri; Wahyu Indratno, Sapto

2018-01-01

Multi-response optimization is an optimization process by considering multiple responses simultaneously. The purpose of this research is to get the optimum point on multi-response optimization process using grey relational analysis and fuzzy logic method. The optimum point is determined from the Fuzzy-GRG (Grey Relational Grade) variable which is the conversion of the Signal to Noise Ratio of the responses involved. The case study used in this research are case optimization of electrical process parameters in electrical disharge machining. It was found that the combination of treatments resulting to optimum MRR and SR was a 70 V gap voltage factor, peak current 9 A and duty factor 0.8.

Green piezoelectric for autonomous smart textile

NASA Astrophysics Data System (ADS)

Lemaire, E.; Borsa, C. J.; Briand, D.

2015-12-01

In this work, the fabrication of Rochelle salt based piezoelectric textiles are shown. Structures composed of fibers and Rochelle salt are easily produced using green processes. Both manufacturing and the material itself are really efficient in terms of environmental impact, considering the fabrication processes and the material resources involved. Additionally Rochelle salt is biocompatible. In this green paradigm, active sensing or actuating textiles are developed. Thus processing method and piezoelectric properties have been studied: (1) pure crystals are used as acoustic actuator, (2) fabrication of the textile-based composite is detailed, (3) converse effective d33 is evaluated and compared to lead zirconate titanate ceramic. The utility of textile-based piezoelectric merits its use in a wide array of applications.

Hydrogenolysis of 5-carbon sugars, sugar alcohols, and other methods and compositions for reactions involving hydrogen

DOEpatents

Werpy, Todd A [West Richland, WA; Zacher, Alan H [Kennewick, WA

2002-11-12

Methods and compositions for reactions of hydrogen over a Re-containing catalyst with compositions containing a 5-carbon sugar, sugar alcohol, or lactic acid are described. It has been surprisingly discovered that reaction with hydrogen over a Re-containing multimetallic catalyst resulted in superior conversion and selectivity to desired products such as propylene glycol. A process for the synthesis of PG from lactate or lactic acid is also described.

Proteomics identification of differentially expressed proteins in the muscle of dysferlin myopathy patients.

PubMed

De la Torre, Carolina; Illa, Isabel; Faulkner, Georgine; Soria, Laura; Robles-Cedeño, Rene; Dominguez-Perles, Raul; De Luna, Noemí; Gallardo, Eduard

2009-04-01

The muscular dystrophies are a large and heterogeneous group of neuromuscular disorders that can be classified according to the mode of inheritance, the clinical phenotype and the molecular defect. To better understand the pathological mechanisms of dysferlin myopathy we compared the protein-expression pattern in the muscle biopsies of six patients with this disease with six patients with limb girdle muscular dystrophy 2A, five with facioscapulohumeral dystrophy and six normal control subjects. To investigate differences in the expression levels of skeletal muscle proteins we used 2-DE and MS. Western blot or immunohistochemistry confirmed relevant results. The study showed specific increase expression of proteins involved in fast-to-slow fiber type conversion (ankyrin repeat protein 2), type I predominance (phosphorylated forms of slow troponin T), sarcomere stabilization (actinin-associated LIM protein), protein ubiquitination (TRIM 72) and skeletal muscle differentiation (Rho-GDP-dissociation inhibitor ly-GDI) in dysferlin myopathy. As anticipated, we also found differential expression of proteins common to all the muscular dystrophies studied. This comparative proteomic analysis suggests that in dysferlin myopathy (i) the type I fiber predominance is an active process of fiber type conversion rather than a selective loss of type II fibers and (ii) the dysregulation of proteins involved in muscle differentiation further confirms the role of dysferlin in this process. Copyright © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Isonicotinic Acid Hydrazide Conversion to Isonicotinyl-NAD by Catalase-peroxidases*

PubMed Central

Wiseman, Ben; Carpena, Xavi; Feliz, Miguel; Donald, Lynda J.; Pons, Miquel; Fita, Ignacio; Loewen, Peter C.

2010-01-01

Activation of the pro-drug isoniazid (INH) as an anti-tubercular drug in Mycobacterium tuberculosis involves its conversion to isonicotinyl-NAD, a reaction that requires the catalase-peroxidase KatG. This report shows that the reaction proceeds in the absence of KatG at a slow rate in a mixture of INH, NAD+, Mn2+, and O2, and that the inclusion of KatG increases the rate by >7 times. Superoxide, generated by either Mn2+- or KatG-catalyzed reduction of O2, is an essential intermediate in the reaction. Elimination of the peroxidatic process by mutation slows the rate of reaction by 60% revealing that the peroxidatic process enhances, but is not essential for isonicotinyl-NAD formation. The isonicotinyl-NAD•+ radical is identified as a reaction intermediate, and its reduction by superoxide is proposed. Binding sites for INH and its co-substrate, NAD+, are identified for the first time in crystal complexes of Burkholderia pseudomallei catalase-peroxidase with INH and NAD+ grown by co-crystallization. The best defined INH binding sites were identified, one in each subunit, on the opposite side of the protein from the entrance to the heme cavity in a funnel-shaped channel. The NAD+ binding site is ∼20 Å from the entrance to the heme cavity and involves interactions primarily with the AMP portion of the molecule in agreement with the NMR saturation transfer difference results. PMID:20554537

Deep--deeper--deepest? Encoding strategies and the recognition of human faces.

PubMed

Sporer, S L

1991-03-01

Various encoding strategies that supposedly promote deeper processing of human faces (e.g., character judgments) have led to better recognition than more shallow processing tasks (judging the width of the nose). However, does deeper processing actually lead to an improvement in recognition, or, conversely, does shallow processing lead to a deterioration in performance when compared with naturally employed encoding strategies? Three experiments systematically compared a total of 8 different encoding strategies manipulating depth of processing, amount of elaboration, and self-generation of judgmental categories. All strategies that required a scanning of the whole face were basically equivalent but no better than natural strategy controls. The consistently worst groups were the ones that rated faces along preselected physical dimensions. This can be explained by subjects' lesser task involvement as revealed by manipulation checks.

Young Children's Persuasion in Everyday Conversation: Tactics and Attunement to Others' Mental States

ERIC Educational Resources Information Center

Bartsch, Karen; Wright, Jennifer Cole; Estes, David

2010-01-01

Young children's persuasion tactics, and how these reflected attunement to others' mental states, were explored in archived longitudinal samples of transcribed at-home conversations of four children, three to five years old. Over 87,000 utterances were examined to identify conversation "chunks" involving persuasion; 1,307 chunks were then coded…

77 FR 60981 - Kinder Morgan Interstate Gas Transmission L.L.C.; Notice of Intent To Prepare an Environmental...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-05

... Pony Express Pipeline Conversion Project and Request for Comments on Environmental Issues The staff of... (EA) that will discuss the environmental impacts of the Pony Express Pipeline Conversion Project involving conversion of facilities from natural gas to oil and construction and operation of new facilities...

Order and Disorder in Conversation: Encounters with Dementia of the Alzheimer's Type

ERIC Educational Resources Information Center

Muller, Nicole; Guendouzi, Jacqueline A.

2005-01-01

After a brief introduction to Dementia of the Alzheimer's Type (DAT), its behavioral diagnostic symptom complex and a summary of communicative implications, we present data from two conversations involving participants with and without DAT. We discuss the concept of "order" in conversation, and the central importance of interactional monitoring.…

24 CFR 972.133 - Public and resident consultation process for developing a conversion plan.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 4 2012-04-01 2012-04-01 false Public and resident consultation process for developing a conversion plan. 972.133 Section 972.133 Housing and Urban Development... ASSISTANCE Required Conversion of Public Housing Developments Conversion Plans § 972.133 Public and resident...

Liquid Fuels from Lignins: Annual Report

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

Chum, H. L.; Johnson, D. K.

1986-01-01

This task was initiated to assess the conversion of lignins into liquid fuels, primarily of lignins relevant to biomass-to-ethanol conversion processes. The task was composed of a literature review of this area and an experimental part to obtain pertinent data on the conversion of lignins germane to biomass-to-ethanol conversion processes.

Neural substrates of sublexical processing for spelling.

PubMed

DeMarco, Andrew T; Wilson, Stephen M; Rising, Kindle; Rapcsak, Steven Z; Beeson, Pélagie M

2017-01-01

We used fMRI to examine the neural substrates of sublexical phoneme-grapheme conversion during spelling in a group of healthy young adults. Participants performed a writing-to-dictation task involving irregular words (e.g., choir), plausible nonwords (e.g., kroid), and a control task of drawing familiar geometric shapes (e.g., squares). Written production of both irregular words and nonwords engaged a left-hemisphere perisylvian network associated with reading/spelling and phonological processing skills. Effects of lexicality, manifested by increased activation during nonword relative to irregular word spelling, were noted in anterior perisylvian regions (posterior inferior frontal gyrus/operculum/precentral gyrus/insula), and in left ventral occipito-temporal cortex. In addition to enhanced neural responses within domain-specific components of the language network, the increased cognitive demands associated with spelling nonwords engaged domain-general frontoparietal cortical networks involved in selective attention and executive control. These results elucidate the neural substrates of sublexical processing during written language production and complement lesion-deficit correlation studies of phonological agraphia. Copyright © 2016 Elsevier Inc. All rights reserved.

Neural Substrates of Sublexical Processing for Spelling

PubMed Central

Wilson, Stephen M.; Rising, Kindle; Rapcsak, Steven Z.; Beeson, Pélagie M.

2016-01-01

We used fMRI to examine the neural substrates of sublexical phoneme-grapheme conversion during spelling in a group of healthy young adults. Participants performed a writing-to-dictation task involving irregular words (e.g., choir), plausible nonwords (e.g., kroid), and a control task of drawing familiar geometric shapes (e.g., squares). Written production of both irregular words and nonwords engaged a left-hemisphere perisylvian network associated with reading/spelling and phonological processing skills. Effects of lexicality, manifested by increased activation during nonword relative to irregular word spelling, were noted in anterior perisylvian regions (posterior inferior frontal gyrus/operculum/precentral gyrus/insula), and in left ventral occipito-temporal cortex. In addition to enhanced neural responses within domain-specific components of the language network, the increased cognitive demands associated with spelling nonwords engaged domain-general frontoparietal cortical networks involved in selective attention and executive control. These results elucidate the neural substrates of sublexical processing during written language production and complement lesion-deficit correlation studies of phonological agraphia. PMID:27838547

Harnessing the power of conversations with virtual humans to change health behaviors.

PubMed

Albright, Glenn; Adam, Cyrille; Serri, Deborah; Bleeker, Seth; Goldman, Ron

2016-01-01

Skillful, collaborative conversations are powerful tools to improve physical and mental health. Whether you are a parent talking with your child about the dangers of substance abuse, an educator concerned about a student's signs of psychological distress, a veteran worried about a buddy who is contemplating suicide, or a healthcare professional wanting to better engage patients to increase treatment compliance, having the skill, confidence and motivation to engage in conversations can truly transform the health and well-being of those you interact with. Kognito develops role-play simulations that prepare individuals to effectively lead real-life conversations that measurably improve social, emotional, and physical health. The behavior change model that drives the simulations draws upon components of game mechanics, virtual human simulation technology and integrates evidence-based instructional design components as well as principles of social-cognitive theory and neuroscience such as motivational interviewing, emotional regulation, empathy and mindfulness. In the simulations, users or enter a risk-free practice environment and engage in a conversation with intelligent, fully animated, and emotionally responsive virtual characters that model human behavior. It is in practicing these conversations, and receiving feedback from a virtual coach, that users learn to better lead conversations in real life. Numerous longitudinal studies have shown that users who complete Kognito simulations demonstrate statistically significant and sustained increases in attitudinal variables that predict behavior change including preparedness, likelihood, and self-efficacy to better manage conversations. Pending the target population, each online or mobile simulation resulted in desired behavior changes ranging from increased referrals of students, patients or veterans in psychological distress to mental health support services, or increasing physician patient-centered communication or patient self-confidence and active involved in the decision-making processes. These simulations have demonstrated a capability to address major health and public health concerns where effective conversations are necessary to bring about changes in attitudes and behaviors.

Harnessing the power of conversations with virtual humans to change health behaviors

PubMed Central

Adam, Cyrille; Serri, Deborah; Bleeker, Seth; Goldman, Ron

2016-01-01

Skillful, collaborative conversations are powerful tools to improve physical and mental health. Whether you are a parent talking with your child about the dangers of substance abuse, an educator concerned about a student’s signs of psychological distress, a veteran worried about a buddy who is contemplating suicide, or a healthcare professional wanting to better engage patients to increase treatment compliance, having the skill, confidence and motivation to engage in conversations can truly transform the health and well-being of those you interact with. Kognito develops role-play simulations that prepare individuals to effectively lead real-life conversations that measurably improve social, emotional, and physical health. The behavior change model that drives the simulations draws upon components of game mechanics, virtual human simulation technology and integrates evidence-based instructional design components as well as principles of social-cognitive theory and neuroscience such as motivational interviewing, emotional regulation, empathy and mindfulness. In the simulations, users or enter a risk-free practice environment and engage in a conversation with intelligent, fully animated, and emotionally responsive virtual characters that model human behavior. It is in practicing these conversations, and receiving feedback from a virtual coach, that users learn to better lead conversations in real life. Numerous longitudinal studies have shown that users who complete Kognito simulations demonstrate statistically significant and sustained increases in attitudinal variables that predict behavior change including preparedness, likelihood, and self-efficacy to better manage conversations. Pending the target population, each online or mobile simulation resulted in desired behavior changes ranging from increased referrals of students, patients or veterans in psychological distress to mental health support services, or increasing physician patient-centered communication or patient self-confidence and active involved in the decision-making processes. These simulations have demonstrated a capability to address major health and public health concerns where effective conversations are necessary to bring about changes in attitudes and behaviors. PMID:28293614

Phone Conversation while Processing Information: Chronometric Analysis of Load Effects in Everyday-media Multitasking

PubMed Central

Steinborn, Michael B.; Huestegge, Lynn

2017-01-01

This is a pilot study that examined the effect of cell-phone conversation on cognition using a continuous multitasking paradigm. Current theorizing argues that phone conversation affects behavior (e.g., driving) by interfering at a level of cognitive processes (not peripheral activity) and by implying an attentional-failure account. Within the framework of an intermittent spare–utilized capacity threading model, we examined the effect of aspects of (secondary-task) phone conversation on (primary-task) continuous arithmetic performance, asking whether phone use makes components of automatic and controlled information-processing (i.e., easy vs. hard mental arithmetic) run more slowly, or alternatively, makes processing run less reliably albeit with the same processing speed. The results can be summarized as follows: While neither expecting a text message nor expecting an impending phone call had any detrimental effects on performance, active phone conversation was clearly detrimental to primary-task performance. Crucially, the decrement imposed by secondary-task (conversation) was not due to a constant slowdown but is better be characterized by an occasional breakdown of information processing, which differentially affected automatic and controlled components of primary-task processing. In conclusion, these findings support the notion that phone conversation makes individuals not constantly slower but more vulnerable to commit attention failure, and in this way, hampers stability of (primary-task) information processing. PMID:28634458

Phone Conversation while Processing Information: Chronometric Analysis of Load Effects in Everyday-media Multitasking.

PubMed

Steinborn, Michael B; Huestegge, Lynn

2017-01-01

This is a pilot study that examined the effect of cell-phone conversation on cognition using a continuous multitasking paradigm. Current theorizing argues that phone conversation affects behavior (e.g., driving) by interfering at a level of cognitive processes (not peripheral activity) and by implying an attentional-failure account. Within the framework of an intermittent spare-utilized capacity threading model, we examined the effect of aspects of (secondary-task) phone conversation on (primary-task) continuous arithmetic performance, asking whether phone use makes components of automatic and controlled information-processing (i.e., easy vs. hard mental arithmetic) run more slowly, or alternatively, makes processing run less reliably albeit with the same processing speed. The results can be summarized as follows: While neither expecting a text message nor expecting an impending phone call had any detrimental effects on performance, active phone conversation was clearly detrimental to primary-task performance. Crucially, the decrement imposed by secondary-task (conversation) was not due to a constant slowdown but is better be characterized by an occasional breakdown of information processing, which differentially affected automatic and controlled components of primary-task processing. In conclusion, these findings support the notion that phone conversation makes individuals not constantly slower but more vulnerable to commit attention failure, and in this way, hampers stability of (primary-task) information processing.

Online Scholarly Conversations in General Education Astronomy Courses

NASA Astrophysics Data System (ADS)

Cai, Qijie; Wong, Ka-Wah

2018-01-01

In general education astronomy courses, many students are struggling with understanding the foundational concepts and theories in astronomy. One of the possible reasons is that, due the large class size, many of the courses are taught using a lecture mode, where human interactions and active learning are limited (Freeman et al., 2014). To address this challenge, we have applied the knowledge building framework (Scardamalia & Bereiter, 2006) to design an online collaborative learning component, called Scholarly Conversations, to be integrated into a general education astronomy course at a public, comprehensive university.During Scholarly Conversations, students are treated as scholars to advance knowledge frontiers (Scardamalia & Bereiter, 2006). The whole process involves the creation of new ideas and requires discourse and collective work for the advancement and creation of artifacts, such as theories and models (van Aalst, 2009). Based on the knowledge building principles (Scardamalia, 2002; Zhang, Scardamalia, Reeve, & Messina, 2009), several features have been built into Scholarly Conversations so that students are guided to deepen understanding of the astronomy concepts through three phases: knowledge sharing, knowledge construction and knowledge building, and reflections on learning growth (van Aalst, 2009; Cai, 2017). The online Scholarly Conversation is an extension of the lecture component of the general education astronomy course. It promotes student interactions and collaborative learning, and provides scaffolds for students to construct meanings of the essential concepts in astronomy through social learning and online technology. In this presentation, we will explain the specific design principles of the online Scholarly Conversation, and share the artifacts created to facilitate the online conversations in an general education astronomy course.Note: This project has been supported by the College of Education Research Grant Program at Minnesota State University, Mankato.

Broadband down-conversion based near infrared quantum cutting in Eu{sup 2+}–Yb{sup 3+} co-doped SrAl{sub 2}O{sub 4} for crystalline silicon solar cells

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

Tai, Yuping, E-mail: yupingtai@126.com; Zheng, Guojun, E-mail: zhengguojun88@126.com; Wang, Hui, E-mail: huiwang@nwu.edu.cn

2015-03-15

Near infrared (NIR) quantum cutting involving the down conversion of an absorbed visible photon to emission of two NIR photons was achieved in SrAl{sub 2}O{sub 4}:0.01Eu{sup 2+}, xYb{sup 3+} (x=0, 1, 2, 5, 10, 20, 30 mol%) samples. The photoluminescence properties of samples in visible and NIR regions were measured to verify the energy transfer (ET) from Eu{sup 2+} to Yb{sup 3+}. The results demonstrated that Eu{sup 2+} was an efficient sensitizer for Yb{sup 3+} in the SrAl{sub 2}O{sub 4} host lattice. According to Gaussian fitting analysis and temperature-dependent luminescence experiments, the conclusion was drawn that the cooperative energy transfermore » (CET) process dominated the ET process and the influence of charge transfer state (CTS) of Yb{sup 3+} could be negligible. As a result, the high energy transfer efficiency (ETE) and quantum yield (QY) have been acquired, the maximum value approached 73.68% and 147.36%, respectively. Therefore, this down-conversion material has potential application in crystalline silicon solar cells to improve conversion efficiency. - Graphical abstract: Near infrared quantum cutting was achieved in Eu{sup 2+}–Yb{sup 3+} co-doped SrAl{sub 2}O{sub 4} samples. The cooperative energy transfer process dominated energy transfer process and high energy transfer efficiency was acquired. - Highlights: • The absorption spectrum of Eu{sup 2+} ion is strong in intensity and broad in bandwidth. • The spectra of Eu{sup 2+} in SrAl{sub 2}O{sub 4} lies in the strongest region of solar spectrum. • The cooperative energy transfer (CET) dominated the energy transfer process. • The domination of CET is confirmed by experimental analysis. • SrAl{sub 2}O{sub 4}:Eu{sup 2+},Yb{sup 3+} show high energy transfer efficiency and long lifetime.« less

The processive kinetics of gene conversion in bacteria

PubMed Central

Paulsson, Johan; El Karoui, Meriem; Lindell, Monica

2017-01-01

Summary Gene conversion, non‐reciprocal transfer from one homologous sequence to another, is a major force in evolutionary dynamics, promoting co‐evolution in gene families and maintaining similarities between repeated genes. However, the properties of the transfer – where it initiates, how far it proceeds and how the resulting conversion tracts are affected by mismatch repair – are not well understood. Here, we use the duplicate tuf genes in Salmonella as a quantitatively tractable model system for gene conversion. We selected for conversion in multiple different positions of tuf, and examined the resulting distributions of conversion tracts in mismatch repair‐deficient and mismatch repair‐proficient strains. A simple stochastic model accounting for the essential steps of conversion showed excellent agreement with the data for all selection points using the same value of the conversion processivity, which is the only kinetic parameter of the model. The analysis suggests that gene conversion effectively initiates uniformly at any position within a tuf gene, and proceeds with an effectively uniform conversion processivity in either direction limited by the bounds of the gene. PMID:28256783

Photoluminescence properties of Mn2+/Yb3+ co-doped oxyfluoride glasses for solar cells application

NASA Astrophysics Data System (ADS)

Yan, Ying; Chen, Zeng; Jia, Xiyang; Li, Shengjun

2018-01-01

Mn2+/Yb3+ co-doped oxyfluoride glasses were facilely synthesized in the SiO2-Al2O3-Na2O-CaF2 system. Partial crystallization processed during the preparation of the glasses, by which small amounts of CaF2 nano-crystals were formed. Under ultraviolet and blue (370-500 nm) light excitation, an efficient down-conversion involving the emission of near-infrared is realized in the Mn2+/Yb3+ co-doped oxyfluoride glasses. The near-infrared emission peaks mainly at 976 nm and secondarily at 1020 nm, which is a comfortable match with the band gap of c-Si. The variation in visible and near-infrared spectra and the decay curves of Mn2+:4T1 → 6A1 emission have been investigated to verify the possible energy transfer from Mn2+ ions to Yb3+ ions. On analyzing the energy transfer processes theoretically and experimentally, we propose that quantum cutting and down-shifting processes may occur simultaneously in the samples. We suggest that the Mn2+-Yb3+ co-doped materials can provide a novel direction to realize UV-Vis to NIR down-conversion for Si solar cells.

CRPS: A contingent hypothesis with prostaglandins as crucial conversion factor.

PubMed

van der Veen, Phe

2015-11-01

CRPS is an acute pain disease expressed as chronic pain with a severe loss of tissue and function. CRPS usually occurs after minor injuries and then progresses in a way that is scarcely controllable, or completely uncontrollable. This article addresses the functional control mechanism of a biological organism, a comparison of techniques, and the way the negative feedback mechanisms fail in regulated feedback systems. The measurement and regulation system is controlled at the local, regional, and central levels in a biological system. Locally generated substances such as prostaglandins and hormones, as well as the central nervous system, play important roles in this process. Prostaglandins fulfil many conversion functions and are involved in vasoactive processes, pain, and inflammation. They play an intermediating role between the activity of the autonomic nervous system and local occurrences. The insufficiently explored conversion function of prostaglandins as a ubiquitously present cofactor may be related to the development of CRPS at sites which have had minor injuries in the past. Chronic Regional Pain Syndrome (CRPS) is a moderately prevalent disease, which occurs more frequently with age. Even though there are diseases known to have a precipitating effect on the aetiology of CRPS, for example Carpal tunnel syndrome, the mechanism of onset is unknown. The disease falls under the category of chronic pain, and seldom has an effective treatment based on scientific research. The economic and psychosocial aspects of the disease are substantial. CRPS is the final position of a positive feedback measurement and control system. Homoeostasis is directed by measurement and control processes. In electronics, a rapid conversion system, which quickly adapts to changing circumstances, superimposed with a delayed conversion system, which ensures a stable basis of homoeostasis. Measured changes are compensatorily controlled. An analogy is expected for a Complex Adaptive System such as a living organism. Hormonal systems are slow systems, suitable for stabilising activity. Neural reflex systems function quickly. Prostaglandins that come from local tissue may be the link between the slow and rapid control. In electronics, negative feedback can convert into a feedback loop which results in the dysregulation, which is what prostaglandins do in biochemistry. A dysregulated feedback control mechanism only has two positions: a zero position and a final position. The process is not easily influenced by other factors. Only phase shifting and signal weakness can affect the feedback process. Theoretically, prostaglandins can also affect this process. Copyright © 2015 Elsevier Ltd. All rights reserved.

The morphing of geographical features by Fourier transformation

PubMed Central

Liu, Pengcheng; Yu, Wenhao; Cheng, Xiaoqiang

2018-01-01

This paper presents a morphing model of vector geographical data based on Fourier transformation. This model involves three main steps. They are conversion from vector data to Fourier series, generation of intermediate function by combination of the two Fourier series concerning a large scale and a small scale, and reverse conversion from combination function to vector data. By mirror processing, the model can also be used for morphing of linear features. Experimental results show that this method is sensitive to scale variations and it can be used for vector map features’ continuous scale transformation. The efficiency of this model is linearly related to the point number of shape boundary and the interceptive value n of Fourier expansion. The effect of morphing by Fourier transformation is plausible and the efficiency of the algorithm is acceptable. PMID:29351344

Up-conversion fluorescence: noncoherent excitation by sunlight.

PubMed

Baluschev, S; Miteva, T; Yakutkin, V; Nelles, G; Yasuda, A; Wegner, G

2006-10-06

We demonstrate up-conversion of noncoherent sunlight realized by ultralow excitation intensity. The bimolecular up-conversion process in our systems relies on the presence of a metastable triplet excited state, and thus has dramatically different photophysical characteristics relative to the other known methods for photon up-conversion (two-photon absorption, parametric processes, second harmonic generation, sequential multiphoton absorption, etc.).

Surface modification of ZSM-5 zeolite: effect of cation on selective conversion of biomass-derived oil

NASA Astrophysics Data System (ADS)

Widayatno, W. B.

2017-04-01

This paper reports the surface modification of high silica ZSM-5 zeolite, particularly emphasizing the effect of cation type on selective conversion of biomass-derived oil. XRD spectra of the NaOH-treated HZSM-5 showed notable crystallinity decrease at specific crystal plane orientation. The N2-physisorption tests confirmed mesoporosity evolution as NaOH concentration was increased. NH3-desorption tests revealed a significant change on surface acidity which involved realumination and cation replacement processes. The utilization of untreated HZSM-5 as well as hierarchical NaZSM-5 for catalytic conversion of bio-oil showed the effect of cation type and mesoporosity on chemicals distribution. The untreated HZSM-5 showed high selectivity to aromatics, which degraded gradually due to deactivation and poisoning of the acid sites. Meanwhile, hierarchical NaZSM-5 showed high selectivity to phenolic compound, which became more stable for 0.4M NaOH-treated zeolite (Na04). The current findings provide an additional insight on the potentials of NaZSM-5 for bio-oil valorization.

Microwave-to-optical frequency conversion using a cesium atom coupled to a superconducting resonator

NASA Astrophysics Data System (ADS)

Gard, Bryan T.; Jacobs, Kurt; McDermott, R.; Saffman, M.

2017-07-01

A candidate for converting quantum information from microwave to optical frequencies is the use of a single atom that interacts with a superconducting microwave resonator on one hand and an optical cavity on the other. The large electric dipole moments and microwave transition frequencies possessed by Rydberg states allow them to couple strongly to superconducting devices. Lasers can then be used to connect a Rydberg transition to an optical transition to realize the conversion. Since the fundamental source of noise in this process is spontaneous emission from the atomic levels, the resulting control problem involves choosing the pulse shapes of the driving lasers so as to maximize the transfer rate while minimizing this loss. Here we consider the concrete example of a cesium atom, along with two specific choices for the levels to be used in the conversion cycle. Under the assumption that spontaneous emission is the only significant source of errors, we use numerical optimization to determine the likely rates for reliable quantum communication that could be achieved with this device. These rates are on the order of a few megaqubits per second.

Formation of zinc protoporphyrin IX in Parma-like ham without nitrate or nitrite.

PubMed

Wakamatsu, Jun-ichi; Uemura, Juichi; Odagiri, Hiroko; Okui, Jun; Hayashi, Nobutaka; Hioki, Shoji; Nishimura, Takanori; Hattori, Akihito

2009-04-01

Zinc protoporphyrin IX (ZPP) is a characteristic red pigment in meat products that are manufactured without the addition of a curing agent such as nitrate or nitrite. To examine the effects of impurities such as mineral components in sea salt on the formation of ZPP, we manufactured Parmatype dry-cured hams that were salted with refined salt or sea salt and examined the involvement of oxidation-reduction potential (ORP) in the formation of ZPP. The content of ZPP was increased drastically after 40 weeks. Microscopic observation showed strong fluorescence caused by ZPP muscle fiber after 40 weeks. Conversely, heme content varied considerably during processing. ORP increased during processing. However, there was no obvious difference between ham salted with refined salt and that salted with sea salt. Therefore, it was concluded that impurities in sea salt were not involved in the formation of ZPP.

Biochemical Conversion: Using Enzymes, Microbes, and Catalysis to Make Fuels and Chemicals

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

None

2013-07-26

This fact sheet describes the Bioenergy Technologies Office's biochemical conversion work and processes. BETO conducts collaborative research, development, and demonstration projects to improve several processing routes for the conversion of cellulosic biomass.

Functional networks of motor inhibition in conversion disorder patients and feigning subjects.

PubMed

Hassa, Thomas; de Jel, Esther; Tuescher, Oliver; Schmidt, Roger; Schoenfeld, Mircea Ariel

2016-01-01

The neural correlates of motor inhibition leading to paresis in conversion disorder are not well known. The key question is whether they are different of those of normal subjects feigning the symptoms. Thirteen conversion disorder patients with hemiparesis and twelve healthy controls were investigated using functional magnetic resonance tomography under conditions of passive motor stimulation of the paretic/feigned paretic and the non-paretic hand. Healthy controls were also investigated in a non-feigning condition. During passive movement of the affected right hand conversion disorder patients exhibited activations in the bilateral triangular part of the inferior frontal gyri (IFG), with a left side dominance compared to controls in non-feigning condition. Feigning controls revealed for the same condition a weak unilateral activation in the right triangular part of IFG and an activity decrease in frontal midline areas, which couldn't be observed in patients. The results suggest that motor inhibition in conversion disorder patients is mediated by the IFG that was also involved in inhibition processes in normal subjects. The activity pattern in feigning controls resembled that of conversion disorder patients but with a clear difference in the medial prefrontal cortex. Healthy controls showed decreased activity in this region during feigning compared to non-feigning conditions suggesting a reduced sense of self-agency during feigning. Remarkably, no activity differences could be observed in medial prefrontal cortex for patients vs healthy controls in feigning or non-feigning conditions suggesting self-agency related activity in patients to be in between those of non-feigning and feigning healthy subjects.

Inter- and Intraspecies Phylogenetic Analyses Reveal Extensive X–Y Gene Conversion in the Evolution of Gametologous Sequences of Human Sex Chromosomes

PubMed Central

Trombetta, Beniamino; Sellitto, Daniele; Scozzari, Rosaria; Cruciani, Fulvio

2014-01-01

It has long been believed that the male-specific region of the human Y chromosome (MSY) is genetically independent from the X chromosome. This idea has been recently dismissed due to the discovery that X–Y gametologous gene conversion may occur. However, the pervasiveness of this molecular process in the evolution of sex chromosomes has yet to be exhaustively analyzed. In this study, we explored how pervasive X–Y gene conversion has been during the evolution of the youngest stratum of the human sex chromosomes. By comparing about 0.5 Mb of human–chimpanzee gametologous sequences, we identified 19 regions in which extensive gene conversion has occurred. From our analysis, two major features of these emerged: 1) Several of them are evolutionarily conserved between the two species and 2) almost all of the 19 hotspots overlap with regions where X–Y crossing-over has been previously reported to be involved in sex reversal. Furthermore, in order to explore the dynamics of X–Y gametologous conversion in recent human evolution, we resequenced these 19 hotspots in 68 widely divergent Y haplogroups and used publicly available single nucleotide polymorphism data for the X chromosome. We found that at least ten hotspots are still active in humans. Hence, the results of the interspecific analysis are consistent with the hypothesis of widespread reticulate evolution within gametologous sequences in the differentiation of hominini sex chromosomes. In turn, intraspecific analysis demonstrates that X–Y gene conversion may modulate human sex-chromosome-sequence evolution to a greater extent than previously thought. PMID:24817545

Food waste-to-energy conversion technologies: current status and future directions.

PubMed

Pham, Thi Phuong Thuy; Kaushik, Rajni; Parshetti, Ganesh K; Mahmood, Russell; Balasubramanian, Rajasekhar

2015-04-01

Food waste represents a significantly fraction of municipal solid waste. Proper management and recycling of huge volumes of food waste are required to reduce its environmental burdens and to minimize risks to human health. Food waste is indeed an untapped resource with great potential for energy production. Utilization of food waste for energy conversion currently represents a challenge due to various reasons. These include its inherent heterogeneously variable compositions, high moisture contents and low calorific value, which constitute an impediment for the development of robust, large scale, and efficient industrial processes. Although a considerable amount of research has been carried out on the conversion of food waste to renewable energy, there is a lack of comprehensive and systematic reviews of the published literature. The present review synthesizes the current knowledge available in the use of technologies for food-waste-to-energy conversion involving biological (e.g. anaerobic digestion and fermentation), thermal and thermochemical technologies (e.g. incineration, pyrolysis, gasification and hydrothermal oxidation). The competitive advantages of these technologies as well as the challenges associated with them are discussed. In addition, the future directions for more effective utilization of food waste for renewable energy generation are suggested from an interdisciplinary perspective. Copyright © 2014 Elsevier Ltd. All rights reserved.

Communication Preferences of Pediatric Cancer Patients: Talking about Prognosis and Their Future Life

PubMed Central

Brand, Sarah R; Fasciano, Karen; Mack, Jennifer W

2017-01-01

Purpose The American Academy of Pediatrics recommends that healthcare providers communicate information to patients in a truthful and developmentally appropriate manner. However there is limited guidance about how to translate these recommendations into clinical practice. The aim of this study was to explore how young cancer patients experienced communication around their illness, especially communication about possible outcomes from disease or treatment. Methods Participants included young people ages 8 to under 18 years with cancer (N=16). Semi-structured interviews focused on their expectations about the future, the process of information exchange, and their preferences for communication within the pediatric oncology setting. Results Overall, participants wanted medical information to be provided to them by their healthcare providers and wanted to be direct participants in medical conversations. However, many participants displayed some ambivalence or conveyed conflicting wishes for prognostic information. For example, some participants reported that they were satisfied with what they knew, but later raised lingering questions. While not the focus of the study, almost every participant discussed social concerns as a key concern for their present and future life. Conclusions While most pediatric cancer patients want to be involved in conversations about their cancer care, including conversations about prognosis, this is an individual and sometimes fluctuating decision, and healthcare providers should be encouraged to discuss preferences for involvement with patients and families. This study highlights the importance of understanding the developmental factors that make pediatric patients unique, especially with regards to their patterns of communication. PMID:27747479

Communication preferences of pediatric cancer patients: talking about prognosis and their future life.

PubMed

Brand, Sarah R; Fasciano, Karen; Mack, Jennifer W

2017-03-01

The American Academy of Pediatrics recommends that healthcare providers communicate information to patients in a truthful and developmentally appropriate manner. However, there is limited guidance about how to translate these recommendations into clinical practice. The aim of this study was to explore how young cancer patients experienced communication around their illness, especially communication about possible outcomes from disease or treatment. Participants included young people ages 8 to under 18 years with cancer (N = 16). Semi-structured interviews focused on their expectations about the future, the process of information exchange, and their preferences for communication within the pediatric oncology setting. Overall, participants wanted medical information to be provided to them by their healthcare providers and wanted to be direct participants in medical conversations. However, many participants displayed some ambivalence or conveyed conflicting wishes for prognostic information. For example, some participants reported that they were satisfied with what they knew, but later raised lingering questions. While not the focus of the study, almost every participant discussed social concerns as a key concern for their present and future life. While most pediatric cancer patients want to be involved in conversations about their cancer care, including conversations about prognosis, this is an individual and sometimes fluctuating decision, and healthcare providers should be encouraged to discuss preferences for involvement with patients and families. This study highlights the importance of understanding the developmental factors that make pediatric patients unique, especially with regard to their patterns of communication.

Effect of Different Types of Small-Group Activities on Students' Conversations

ERIC Educational Resources Information Center

Young, Krista K.; Talanquer, Vicente

2013-01-01

Teaching reform efforts in chemistry education often involve engaging students in small-group activities of different types. This study focused on the analysis of how activity type affected the nature of group conversations. In particular, we analyzed the small-group conversations of students enrolled in a chemistry course for nonscience majors.…

Raman-Suppressing Coupling for Optical Parametric Oscillator

NASA Technical Reports Server (NTRS)

Savchenkov, Anatoliy; Maleki, Lute; Matsko, Andrey; Rubiola, Enrico

2007-01-01

A Raman-scattering-suppressing input/ output coupling scheme has been devised for a whispering-gallery-mode optical resonator that is used as a four-wave-mixing device to effect an all-optical parametric oscillator. Raman scattering is undesired in such a device because (1) it is a nonlinear process that competes with the desired nonlinear four-wave conversion process involved in optical parametric oscillation and (2) as such, it reduces the power of the desired oscillation and contributes to output noise. The essence of the present input/output coupling scheme is to reduce output loading of the desired resonator modes while increasing output loading of the undesired ones.

A new readily processable polyimide

NASA Technical Reports Server (NTRS)

Harris, F. W.; Beltz, M. W.; Hergenrother, P. M.

1986-01-01

As part of an effort to develop tough solvent resistance thermoplastics for potential use as structural resins on aerospace vehicles, a new processable polyimide was evaluated. The synthesis involved the reaction of a new diamine, 1,3-bis 2-(3-aminophenoxy)ethyl ether, with 3,3',4,4'-benzophenonetetracarboxylic dianhydride to form the polyamic acid and subsequent conversion of it to the polyimide. Various physical properties such as thermal stability, solvent resistance, glass transition temperature, crystalline melt temperature, melt viscosity and mechanical properties such as fracture toughness, adhesive, film and composite properties are reported. Of particular interest is the extremely high titanium to titanium tensile shear strength obtained for this polyimide.

Language processing and forms of immediate echolalia in autistic children.

PubMed

Paccia, J M; Curcio, F

1982-03-01

Several aspects of echolalic speech produced by five autistic children were investigated. We found that the incidence of echolalia was influenced by the type of question addressed to the child and, to a lesser extent, by the child's comprehension of the specific relationships expressed in the question. Additionally, acoustic analysis showed that a substantial proportion of echoes involved a prosodic modification of the examiner's question. Further analyses indicated that some of these modified echoes represent more than just a primitive conversational strategy. Specifically, they seem to reflect a higher level of processing and serve a semantic function, that of affirming the examiner's question.

Clustering mechanism of oxocarboxylic acids involving hydration reaction: Implications for the atmospheric models

NASA Astrophysics Data System (ADS)

Liu, Ling; Kupiainen-Määttä, Oona; Zhang, Haijie; Li, Hao; Zhong, Jie; Kurtén, Theo; Vehkamäki, Hanna; Zhang, Shaowen; Zhang, Yunhong; Ge, Maofa; Zhang, Xiuhui; Li, Zesheng

2018-06-01

The formation of atmospheric aerosol particles from condensable gases is a dominant source of particulate matter in the boundary layer, but the mechanism is still ambiguous. During the clustering process, precursors with different reactivities can induce various chemical reactions in addition to the formation of hydrogen bonds. However, the clustering mechanism involving chemical reactions is rarely considered in most of the nucleation process models. Oxocarboxylic acids are common compositions of secondary organic aerosol, but the role of oxocarboxylic acids in secondary organic aerosol formation is still not fully understood. In this paper, glyoxylic acid, the simplest and the most abundant atmospheric oxocarboxylic acid, has been selected as a representative example of oxocarboxylic acids in order to study the clustering mechanism involving hydration reactions using density functional theory combined with the Atmospheric Clusters Dynamic Code. The hydration reaction of glyoxylic acid can occur either in the gas phase or during the clustering process. Under atmospheric conditions, the total conversion ratio of glyoxylic acid to its hydration reaction product (2,2-dihydroxyacetic acid) in both gas phase and clusters can be up to 85%, and the product can further participate in the clustering process. The differences in cluster structures and properties induced by the hydration reaction lead to significant differences in cluster formation rates and pathways at relatively low temperatures.

Śodhana: An Ayurvedic process for detoxification and modification of therapeutic activities of poisonous medicinal plants

PubMed Central

Maurya, Santosh Kumar; Seth, Ankit; Laloo, Damiki; Singh, Narendra Kumar; Gautam, Dev Nath Singh; Singh, Anil Kumar

2015-01-01

Ayurveda involves the use of drugs obtained from plants, animals, and mineral origin. All the three sources of drugs can be divided under poisonous and nonpoisonous category. There are various crude drugs, which generally possess unwanted impurities and toxic substances, which can lead to harmful health problems. Many authors have reported that not all medicinal plants are safe to use since they can bear many toxic and harmful phytoconstituents in them. Śodhana (detoxification/purification) is the process, which involves the conversion of any poisonous drug into beneficial, nonpoisonous/nontoxic ones. Vatsanābha (Aconitum species), Semecarpus anacardium, Strychnos nux-vomica, Acorus calamus, Abrus precatorius etc., are some of the interesting examples of toxic plants, which are still used in the Indian system of medicine. Aconite, bhilawanols, strychnine, β–asarone, abrin are some of the toxic components present in these plants and are relatively toxic in nature. Śodhana process involves the purification as well as reduction in the levels of toxic principles which sometimes results in an enhanced therapeutic efficacy. The present review is designed to extensively discuss and understand the scientific basis of the alternative use of toxic plants as a medicine after their purification process. PMID:26283803

Surface pre-treatment of aluminium by cleaning, chemical ething and conversion coating

NASA Astrophysics Data System (ADS)

Zaki, Mohammad Hafizudden Mohd; Mohd, Yusairie; Isa, Nik Norziehana Che

2017-12-01

Surface pre-treatment is one of the critical treatments for surface modification of aluminium (Al). In this study, pre-treatment of Al surface involved three stages; (1) cleaning (polishing and degreasing), (2) chemical etching (alkaline and acid) and (3) conversion coating (ie: zincate treatment). Cleaning process of Al was conducted by polishing and degreasing with acetone while etching process was done by immersion in 1.25 M NaOH solution (i.e: alkaline etching) followed with acid etching using 8 M HNO3 solution. The zincate treatment was conducted via electroless coating method by immersion of Al into a bath solution containing 0.5 M Zn(NO3)2, 0.1 M HNO3 and 0.2 M NaBH4 (reducing agent) for one hour. Different temperatures (ie: 25 °C, 50 °C, 75 °C, 90 °C) of bath solutions at pH 4 were used to investigate the effect of temperature on zincate treatment. Surface morphology and chemical composition of the pre-treated Al were characterized using Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersion X-ray analysis (EDX), respectively. The results showed that oxide layer on Al surface decreased after chemical etching process. Temperature of zincate solution has significantly affected the conversion coating process of aluminium. It was found that zinc oxide (ZnO) and zinc borate (ZnO.B2O3) were dominantly formed after zincate treatment at high temperature (ie:90 °C) with curved blade-like structure and composition of Zn, B and O with 13.70 wt.%, 3.52 wt.% and 54.39 wt.%, respectively. However, zincate treatment at low temperature (ie:<50 °C) has produced low metallic Zn.

The impact of biotechnological advances on the future of US bioenergy

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

Davison, Brian H.; Brandt, Craig C.; Guss, Adam M.

Modern biotechnology has the potential to substantially advance the feasibility, structure, and efficiency of future biofuel supply chains. Advances might be direct or indirect. A direct advance would be improving the efficiency of biochemical conversion processes and feedstock production. Direct advances in processing may involve developing improved enzymes and bacteria to convert lignocellulosic feedstocks to ethanol. Progress in feedstock production could include enhancing crop yields via genetic modification or the selection of specific natural variants and breeds. Other direct results of biotechnology might increase the production of fungible biofuels and bioproducts, which would impact the supply chain. Indirect advances mightmore » include modifications to dedicated bioenergy crops that enable them to grow on marginal lands rather than land needed for food production. This study assesses the feasibility and advantages of near-future (10-year) biotechnological developments for a US biomass-based supply chain for bioenergy production. We assume a simplified supply chain of feedstock, logistics and land use, conversion, and products and utilization. The primary focus is how likely developments in feedstock production and conversion technologies will impact bioenergy and biofuels in the USA; a secondary focus is other innovative uses of biotechnologies in the energy arenas. The assessment addresses near-term biofuels based on starch, sugar, and cellulosic feedstocks and considers some longer-term options, such as oil-crop and algal technologies.« less

The impact of biotechnological advances on the future of US bioenergy

DOE PAGES

Davison, Brian H.; Brandt, Craig C.; Guss, Adam M.; ...

2015-05-14

Modern biotechnology has the potential to substantially advance the feasibility, structure, and efficiency of future biofuel supply chains. Advances might be direct or indirect. A direct advance would be improving the efficiency of biochemical conversion processes and feedstock production. Direct advances in processing may involve developing improved enzymes and bacteria to convert lignocellulosic feedstocks to ethanol. Progress in feedstock production could include enhancing crop yields via genetic modification or the selection of specific natural variants and breeds. Other direct results of biotechnology might increase the production of fungible biofuels and bioproducts, which would impact the supply chain. Indirect advances mightmore » include modifications to dedicated bioenergy crops that enable them to grow on marginal lands rather than land needed for food production. This study assesses the feasibility and advantages of near-future (10-year) biotechnological developments for a US biomass-based supply chain for bioenergy production. We assume a simplified supply chain of feedstock, logistics and land use, conversion, and products and utilization. The primary focus is how likely developments in feedstock production and conversion technologies will impact bioenergy and biofuels in the USA; a secondary focus is other innovative uses of biotechnologies in the energy arenas. The assessment addresses near-term biofuels based on starch, sugar, and cellulosic feedstocks and considers some longer-term options, such as oil-crop and algal technologies.« less

On the formation of anions: frequency-, angle-, and time-resolved photoelectron imaging of the menadione radical anion† †Electronic supplementary information (ESI) available: A summary of the ground-state geometries and molecular orbitals from the ab initio calculations; fitted residuals from the FA-PI simulation; plots of all spectra included in the frequency-resolved two-dimensional figure; and example time-resolved PE spectra from the 3.10 + 1.55 eV pump-probe experiments. See DOI: 10.1039/c4sc03491k Click here for additional data file.

PubMed Central

Bull, James N.; West, Christopher W.

2015-01-01

Frequency-, angle-, and time-resolved photoelectron imaging of gas-phase menadione (vitamin K3) radical anions was used to show that quasi-bound resonances of the anion can act as efficient doorway states to produce metastable ground electronic state anions on a sub-picosecond timescale. Several anion resonances have been experimentally observed and identified with the assistance of ab initio calculations, and ground state anion recovery was observed across the first 3 eV above threshold. Time-resolved measurements revealed the mechanism of electronic ground state anion formation, which first involves a cascade of very fast internal conversion processes to a bound electronic state that, in turn, decays by slower internal conversion to the ground state. Autodetachment processes from populated resonances are inefficient compared with electronic relaxation through internal conversion. The mechanistic understanding gained provides insight into the formation of radical anions in biological and astrochemical systems. PMID:29560245

Role of Polymeric Excipients in the Stabilization of Olanzapine when Exposed to Aqueous Environments.

PubMed

Paisana, Maria; Wahl, Martin; Pinto, João

2015-12-12

Hydrate formation is a phase transition which can occur during manufacturing processes involving water. This work considers the prevention of hydration of anhydrous olanzapine and hydrate conversions in the presence of water and polymers (polyethyleneglycol; hydroxypropylcellulose; polyvinylpyrrolidone) in forming pellets by wet extrusion and spheronisation. Anhydrous olanzapine was added to water with or without those polymers prior to extrusion with microcrystalline cellulose. Assessment of olanzapine conversion was made by XRP-Diffraction; FTIR spectroscopy; calorimetry (DSC) and microscopy (SEM for crystal size and shape). The addition of water converted the anhydrous form into dihydrate B and higher hydrate; whereas polyethyleneglycol promoted a selective hydrate conversion into the higher hydrate olanzapine form. Both polyvinylpyrrolidone and hydroxypropylcellulose prevented the hydrate transformations of the anhydrous drug; the latter even in the presence of hydrate seeds. This may be explained by the higher H-bond ability; higher network association and higher hydrophobicity of hydroxypropylcellulose by comparison with polyethyleneglycol and polyvinylpyrrolidone; which could contribute to its higher affinity to the crystal surfaces of the hydrate nuclei/initial crystals and promoting steric hindrance to the incorporation of other drug molecules into the crystal lattice; thus, preventing the crystal growth. The addition of microcrystalline cellulose needed for the pellets production (final product) did not eliminate the protector effect of both hydroxypropylcellulose and polyvinylpyrrolidone during pellets' processing and dissolution evaluation.

Endotoxin induces fibrosis in vascular endothelial cells through a mechanism dependent on transient receptor protein melastatin 7 activity.

PubMed

Echeverría, Cesar; Montorfano, Ignacio; Hermosilla, Tamara; Armisén, Ricardo; Velásquez, Luis A; Cabello-Verrugio, Claudio; Varela, Diego; Simon, Felipe

2014-01-01

The pathogenesis of systemic inflammatory diseases, including endotoxemia-derived sepsis syndrome, is characterized by endothelial dysfunction. It has been demonstrated that the endotoxin lipopolysaccharide (LPS) induces the conversion of endothelial cells (ECs) into activated fibroblasts through endothelial-to-mesenchymal transition mechanism. Fibrogenesis is highly dependent on intracellular Ca2+ concentration increases through the participation of calcium channels. However, the specific molecular identity of the calcium channel that mediates the Ca2+ influx during endotoxin-induced endothelial fibrosis is still unknown. Transient receptor potential melastatin 7 (TRPM7) is a calcium channel that is expressed in many cell types, including ECs. TRPM7 is involved in a number of crucial processes such as the conversion of fibroblasts into activated fibroblasts, or myofibroblasts, being responsible for the development of several characteristics of them. However, the role of the TRPM7 ion channel in endotoxin-induced endothelial fibrosis is unknown. Thus, our aim was to study whether the TRPM7 calcium channel participates in endotoxin-induced endothelial fibrosis. Using primary cultures of ECs, we demonstrated that TRPM7 is a crucial protein involved in endotoxin-induced endothelial fibrosis. Suppression of TRPM7 expression protected ECs from the fibrogenic process stimulated by endotoxin. Downregulation of TRPM7 prevented the endotoxin-induced endothelial markers decrease and fibrotic genes increase in ECs. In addition, TRPM7 downregulation abolished the endotoxin-induced increase in ECM proteins in ECs. Furthermore, we showed that intracellular Ca2+ levels were greatly increased upon LPS challenge in a mechanism dependent on TRPM7 expression. These results demonstrate that TRPM7 is a key protein involved in the mechanism underlying endotoxin-induced endothelial fibrosis.

34 CFR 300.501 - Opportunity to examine records; parent participation in meetings.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conversations involving public agency personnel and conversations on issues such as teaching methodology, lesson... relating to the educational placement of their child, the public agency must use other methods to ensure...

34 CFR 300.501 - Opportunity to examine records; parent participation in meetings.

Code of Federal Regulations, 2011 CFR

2011-07-01

... conversations involving public agency personnel and conversations on issues such as teaching methodology, lesson... relating to the educational placement of their child, the public agency must use other methods to ensure...

34 CFR 300.501 - Opportunity to examine records; parent participation in meetings.

Code of Federal Regulations, 2013 CFR

2013-07-01

... conversations involving public agency personnel and conversations on issues such as teaching methodology, lesson... relating to the educational placement of their child, the public agency must use other methods to ensure...

34 CFR 300.501 - Opportunity to examine records; parent participation in meetings.

Code of Federal Regulations, 2014 CFR

2014-07-01

... conversations involving public agency personnel and conversations on issues such as teaching methodology, lesson... relating to the educational placement of their child, the public agency must use other methods to ensure...

34 CFR 300.501 - Opportunity to examine records; parent participation in meetings.

Code of Federal Regulations, 2012 CFR

2012-07-01

... conversations involving public agency personnel and conversations on issues such as teaching methodology, lesson... relating to the educational placement of their child, the public agency must use other methods to ensure...

Preliminary System Analysis of In Situ Resource Utilization for Mars Human Exploration

NASA Technical Reports Server (NTRS)

Rapp, Donald; Andringa, Jason; Easter, Robert; Smith, Jeffrey H .; Wilson, Thomas; Clark, D. Larry; Payne, Kevin

2005-01-01

We carried out a system analysis of processes for utilization of Mars resources to support human exploration of Mars by production of propellants from indigenous resources. Seven ISRU processes were analyzed to determine mass. power and propellant storage volume requirements. The major elements of each process include C02 acquisition, chemical conversion, and storage of propellants. Based on a figure of merit (the ratio of the mass of propellants that must be brought from Earth in a non-ISRU mission to the mass of the ISRU system. tanks and feedstocks that must be brought from Earth for a ISRU mission) the most attractive process (by far); is one where indigenous Mars water is accessible and this is processed via Sabatier/Electrolysis to methane and oxygen. These processes are technically relatively mature. Other processes with positive leverage involve reverse water gas shift and solid oxide electrolysis.

Effect of band-aligned double absorber layers on photovoltaic characteristics of chemical bath deposited PbS/CdS thin film solar cells.

PubMed

Ho Yeon, Deuk; Chandra Mohanty, Bhaskar; Lee, Seung Min; Soo Cho, Yong

2015-09-23

Here we report the highest energy conversion efficiency and good stability of PbS thin film-based depleted heterojunction solar cells, not involving PbS quantum dots. The PbS thin films were grown by the low cost chemical bath deposition (CBD) process at relatively low temperatures. Compared to the quantum dot solar cells which require critical and multistep complex procedures for surface passivation, the present approach, leveraging the facile modulation of the optoelectronic properties of the PbS films by the CBD process, offers a simpler route for optimization of PbS-based solar cells. Through an architectural modification, wherein two band-aligned junctions are stacked without any intervening layers, an enhancement of conversion efficiency by as much as 30% from 3.10 to 4.03% facilitated by absorption of a wider range of solar spectrum has been obtained. As an added advantage of the low band gap PbS stacked over a wide gap PbS, the devices show stability over a period of 10 days.

Comprehensive near infrared study of Jatropha oil esterification with ethanol for biodiesel production

NASA Astrophysics Data System (ADS)

Oliveira, Alianda Dantas de; Sá, Ananda Franco de; Pimentel, Maria Fernanda; Pacheco, José Geraldo A.; Pereira, Claudete Fernandes; Larrechi, Maria Soledad

2017-01-01

This work presents a comprehensive near infrared study for in-line monitoring of the esterification reaction of high acid oils, such as Jatropha curcas oil, using ethanol. Parallel reactions involved in the process were carried out to select a spectral region that characterizes the evolution of the esterification reaction. Using absorbance intensities at 5176 cm- 1, the conversion and kinetic behaviors of the esterification reaction were estimated. This method was applied to evaluate the influence of temperature and catalyst concentration on the estimates of initial reaction rate and ester conversion as responses to a 22 factorial experimental design. Employment of an alcohol/oil ratio of 16:1, catalyst concentration of 1.5% w/w, and temperatures at 65 °C or 75 °C, made it possible to reduce the initial acidity from 18% to 1.3% w/w, which is suitable for transesterification of high free fatty acid oils for biodiesel production. Using the proposed analytical method in the esterification reaction of raw materials with high free fatty acid content for biodiesel makes the monitoring process inexpensive, fast, simple, and practical.

Laughter Among Deaf Signers

PubMed Central

Provine, Robert R.; Emmorey, Karen

2008-01-01

The placement of laughter in the speech of hearing individuals is not random but “punctuates” speech, occurring during pauses and at phrase boundaries where punctuation would be placed in a transcript of a conversation. For speakers, language is dominant in the competition for the vocal tract since laughter seldom interrupts spoken phrases. For users of American Sign Language, however, laughter and language do not compete in the same way for a single output channel. This study investigated whether laughter occurs simultaneously with signing, or punctuates signing, as it does speech, in 11 signed conversations (with two to five participants) that had at least one instance of audible, vocal laughter. Laughter occurred 2.7 times more often during pauses and at phrase boundaries than simultaneously with a signed utterance. Thus, the production of laughter involves higher order cognitive or linguistic processes rather than the low-level regulation of motor processes competing for a single vocal channel. In an examination of other variables, the social dynamics of deaf and hearing people were similar, with “speakers” (those signing) laughing more than their audiences and females laughing more than males. PMID:16891353

Laughter among deaf signers.

PubMed

Provine, Robert R; Emmorey, Karen

2006-01-01

The placement of laughter in the speech of hearing individuals is not random but "punctuates" speech, occurring during pauses and at phrase boundaries where punctuation would be placed in a transcript of a conversation. For speakers, language is dominant in the competition for the vocal tract since laughter seldom interrupts spoken phrases. For users of American Sign Language, however, laughter and language do not compete in the same way for a single output channel. This study investigated whether laughter occurs simultaneously with signing, or punctuates signing, as it does speech, in 11 signed conversations (with two to five participants) that had at least one instance of audible, vocal laughter. Laughter occurred 2.7 times more often during pauses and at phrase boundaries than simultaneously with a signed utterance. Thus, the production of laughter involves higher order cognitive or linguistic processes rather than the low-level regulation of motor processes competing for a single vocal channel. In an examination of other variables, the social dynamics of deaf and hearing people were similar, with "speakers" (those signing) laughing more than their audiences and females laughing more than males.

Recent progress on understanding the mechanisms of amyloid nucleation.

PubMed

Chatani, Eri; Yamamoto, Naoki

2018-04-01

Amyloid fibrils are supramolecular protein assemblies with a fibrous morphology and cross-β structure. The formation of amyloid fibrils typically follows a nucleation-dependent polymerization mechanism, in which a one-step nucleation scheme has widely been accepted. However, a variety of oligomers have been identified in early stages of fibrillation, and a nucleated conformational conversion (NCC) mechanism, in which oligomers serve as a precursor of amyloid nucleation and convert to amyloid nuclei, has been proposed. This development has raised the need to consider more complicated multi-step nucleation processes in addition to the simplest one-step process, and evidence for the direct involvement of oligomers as nucleation precursors has been obtained both experimentally and theoretically. Interestingly, the NCC mechanism has some analogy with the two-step nucleation mechanism proposed for inorganic and organic crystals and protein crystals, although a more dramatic conformational conversion of proteins should be considered in amyloid nucleation. Clarifying the properties of the nucleation precursors of amyloid fibrils in detail, in comparison with those of crystals, will allow a better understanding of the nucleation of amyloid fibrils and pave the way to develop techniques to regulate it.

Gliotransmission and Brain Glucose Sensing

PubMed Central

Lanfray, Damien; Arthaud, Sébastien; Ouellet, Johanne; Compère, Vincent; Do Rego, Jean-Luc; Leprince, Jérôme; Lefranc, Benjamin; Castel, Hélène; Bouchard, Cynthia; Monge-Roffarello, Boris; Richard, Denis; Pelletier, Georges; Vaudry, Hubert; Tonon, Marie-Christine; Morin, Fabrice

2013-01-01

Hypothalamic glucose sensing is involved in the control of feeding behavior and peripheral glucose homeostasis, and glial cells are suggested to play an important role in this process. Diazepam-binding inhibitor (DBI) and its processing product the octadecaneuropeptide (ODN), collectively named endozepines, are secreted by astroglia, and ODN is a potent anorexigenic factor. Therefore, we investigated the involvement of endozepines in brain glucose sensing. First, we showed that intracerebroventricular administration of glucose in rats increases DBI expression in hypothalamic glial-like tanycytes. We then demonstrated that glucose stimulates endozepine secretion from hypothalamic explants. Feeding experiments indicate that the anorexigenic effect of central administration of glucose was blunted by coinjection of an ODN antagonist. Conversely, the hyperphagic response elicited by central glucoprivation was suppressed by an ODN agonist. The anorexigenic effects of centrally injected glucose or ODN agonist were suppressed by blockade of the melanocortin-3/4 receptors, suggesting that glucose sensing involves endozepinergic control of the melanocortin pathway. Finally, we found that brain endozepines modulate blood glucose levels, suggesting their involvement in a feedback loop controlling whole-body glucose homeostasis. Collectively, these data indicate that endozepines are a critical relay in brain glucose sensing and potentially new targets in treatment of metabolic disorders. PMID:23160530

Carbon dioxide capture from a cement manufacturing process

DOEpatents

Blount, Gerald C [North Augusta, SC; Falta, Ronald W [Seneca, SC; Siddall, Alvin A [Aiken, SC

2011-07-12

A process of manufacturing cement clinker is provided in which a clean supply of CO.sub.2 gas may be captured. The process also involves using an open loop conversion of CaO/MgO from a calciner to capture CO.sub.2 from combustion flue gases thereby forming CaCO.sub.3/CaMg(CO.sub.3).sub.2. The CaCO.sub.3/CaMg(CO.sub.3).sub.2 is then returned to the calciner where CO.sub.2 gas is evolved. The evolved CO.sub.2 gas, along with other evolved CO.sub.2 gases from the calciner are removed from the calciner. The reactants (CaO/MgO) are feed to a high temperature calciner for control of the clinker production composition.

Dehydroindigo, the forgotten indigo and its contribution to the color of Maya Blue.

PubMed

Rondão, Raquel; Seixas de Melo, J Sérgio; Bonifácio, Vasco D B; Melo, Maria J

2010-02-04

A comprehensive investigation of the electronic spectral and photophysical properties of the oxidized form of indigo, dehydroindigo (DHI), has been carried out in solution at 293 K. It is shown that dehydroindigo readily converts into its neutral keto form, the blue indigo, in a process which depends on the solvent and water content of the medium. DHI was investigated in toluene, in benzene, and in methanol and it was found that both the oxidized and the keto indigo forms are present in solution. In marked contrast to what has been found for keto-indigo, where the internal conversion channel dominates >99% of the excited state deactivation, or with the fully reduced leuco-indigo, where fluorescence, internal conversion, and singlet-to-triplet intersystem crossing coexist, in the case of DHI in toluene and benzene, the dominant excited state deactivation channel involves the triplet state. Triplet state yields (phi(T)) of 70-80%, with negligible fluorescence (< or = 0.01%) are observed in these solvents. In methanol the phi(T) value decreases to approximately 15%, with an increase of the fluorescence quantum yield to 2%, which makes these processes competitive with the S(1) --> S(0) internal conversion deactivation process. The data are experimentally compatible with the existence of a lowest lying singlet excited state of n,pi* origin in toluene and of pi,pi* origin in methanol. A time-resolved investigation in the picosecond time domain suggests that the emission of DHI involves three interconnected species (involving rotational isomerism), with relative contributions depending on the emission wavelength. DFT calculations (B3LYP 6-31G** level) were performed in order to characterize the electronic ground (S(0)) and excited singlet (S(1)) and triplet (T(1)) states of DHI. The HOMO-LUMO transition was found to accompany an n --> pi* transition of the oxygen nonbonding orbitals to the central CC and adjacent C-N bonds. Calculations also revealed that in S(0) the two indole-like moieties deviate from planarity from ca. 20 degrees, whereas in S(1) and T(1) the predicted structure is basically planar; a gradual decrease of the carbon-carbon central bond distance is seen in the order S(0), S(1), T(1). An additional study on the blue pigment Maya Blue was made, and the comparison between the solid-state spectra of indigo, DHI, and Maya Blue suggests that, in line with recent investigations, DHI is present together with indigo in Maya Blue. These results are relevant to the discussion of the involvement of dehydroindigo in the palette of colors of the ancient Maya Blue pigment.

Learning How to Feel: Conversion Narratives and Community Membership in First-Year Composition

ERIC Educational Resources Information Center

Kurtyka, Faith M.

2017-01-01

This article examines the rhetoric of the conversion narratives told by a group of women joining a new social sorority on campus. I argue that these sorority conversion narratives are of interest to composition scholars because they document the emotional work involved in entering a community in one's first year of college. My close analysis of…

Emotion-motion interactions in conversion disorder: an FMRI study.

PubMed

Aybek, Selma; Nicholson, Timothy R; O'Daly, Owen; Zelaya, Fernando; Kanaan, Richard A; David, Anthony S

2015-01-01

To evaluate the neural correlates of implicit processing of negative emotions in motor conversion disorder (CD) patients. An event related fMRI task was completed by 12 motor CD patients and 14 matched healthy controls using standardised stimuli of faces with fearful and sad emotional expressions in comparison to faces with neutral expressions. Temporal changes in the sensitivity to stimuli were also modelled and tested in the two groups. We found increased amygdala activation to negative emotions in CD compared to healthy controls in region of interest analyses, which persisted over time consistent with previous findings using emotional paradigms. Furthermore during whole brain analyses we found significantly increased activation in CD patients in areas involved in the 'freeze response' to fear (periaqueductal grey matter), and areas involved in self-awareness and motor control (cingulate gyrus and supplementary motor area). In contrast to healthy controls, CD patients exhibited increased response amplitude to fearful stimuli over time, suggesting abnormal emotional regulation (failure of habituation / sensitization). Patients with CD also activated midbrain and frontal structures that could reflect an abnormal behavioral-motor response to negative including threatening stimuli. This suggests a mechanism linking emotions to motor dysfunction in CD.

Systems biology: a new tool for farm animal science.

PubMed

Hollung, Kristin; Timperio, Anna M; Olivan, Mamen; Kemp, Caroline; Coto-Montes, Ana; Sierra, Veronica; Zolla, Lello

2014-03-01

It is rapidly emerging that the tender meat phenotype is affected by an enormous amount of variables, not only tied to genetics (livestock breeding selection), but also to extrinsic factors, such as feeding conditions, physical activity, rearing environment, administration of hormonal growth promotants, pre-slaughter handling and stress. Proteomics has been widely accepted by meat scientists over the last years and is now commonly used to shed light on the postmortem processes involved in meat tenderization. This review discusses the latest findings with the use of proteomics and systems biology to study the different biochemical pathways postmortem aiming at understanding the concerted action of different molecular mechanisms responsible for meat quality. The conversion of muscle to meat postmortem can be described as a sequence of events involving molecular pathways controlled by a complex interplay of many factors. Among the different pathways emerging are the influence of apoptosis and lately also the role of autophagy in muscle postmortem development. This review thus, focus on how systems-wide integrated investigations (metabolomics, transcriptomics, interactomics, phosphoproteomics, mathematical modeling), which have emerged as complementary tools to proteomics, have helped establishing a few milestones in our understanding of the events leading from muscle to meat conversion.

Strategies to achieve high-solids enzymatic hydrolysis of dilute-acid pretreated corn stover.

PubMed

Geng, Wenhui; Jin, Yongcan; Jameel, Hasan; Park, Sunkyu

2015-01-01

Three strategies were presented to achieve high solids loading while maximizing carbohydrate conversion, which are fed-batch, splitting/thickening, and clarifier processes. Enzymatic hydrolysis was performed at water insoluble solids (WIS) of 15% using washed dilute-acid pretreated corn stover. The carbohydrate concentration increased from 31.8 to 99.3g/L when the insoluble solids content increased from 5% to 15% WIS, while the final carbohydrate conversion was decreased from 78.4% to 73.2%. For the fed-batch process, a carbohydrate conversion efficiency of 76.8% was achieved when solid was split into 60:20:20 ratio, with all enzymes added first. For the splitting/thickening process, a carbohydrate conversion of 76.5% was realized when the filtrate was recycled to simulate a steady-state process. Lastly, the clarifier process was evaluated and the highest carbohydrate conversion of 81.4% was achieved. All of these results suggests the possibility of enzymatic hydrolysis at high solids to make the overall conversion cost-competitive. Copyright © 2015 Elsevier Ltd. All rights reserved.

Listening to a conversation with aggressive content expands the interpersonal space

PubMed Central

Vagnoni, Eleonora; Lewis, Jessica; Tajadura-Jiménez, Ana

2018-01-01

The distance individuals maintain between themselves and others can be defined as ‘interpersonal space’. This distance can be modulated both by situational factors and individual characteristics. Here we investigated the influence that the interpretation of other people interaction, in which one is not directly involved, may have on a person’s interpersonal space. In the current study we measured, for the first time, whether the size of interpersonal space changes after listening to other people conversations with neutral or aggressive content. The results showed that the interpersonal space expands after listening to a conversation with aggressive content relative to a conversation with a neutral content. This finding suggests that participants tend to distance themselves from an aggressive confrontation even if they are not involved in it. These results are in line with the view of the interpersonal space as a safety zone surrounding one’s body. PMID:29590110

Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Biological Conversion of Sugars to Hydrocarbons

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

Davis, R.; Tao, L.; Tan, E. C. D.

2013-10-01

This report describes one potential conversion process to hydrocarbon products by way of biological conversion of lingnocellulosic-dervied sugars. The process design converts biomass to a hydrocarbon intermediate, a free fatty acid, using dilute-acid pretreatement, enzymatic saccharification, and bioconversion. Ancillary areas--feed handling, hydrolysate conditioning, product recovery and upgrading (hydrotreating) to a final blendstock material, wastewater treatment, lignin combusion, and utilities--are also included in the design.

Improved lignocellulose conversion to biofuels with thermophilic bacteria and thermostable enzymes.

PubMed

Bhalla, Aditya; Bansal, Namita; Kumar, Sudhir; Bischoff, Kenneth M; Sani, Rajesh K

2013-01-01

Second-generation feedstock, especially nonfood lignocellulosic biomass is a potential source for biofuel production. Cost-intensive physical, chemical, biological pretreatment operations and slow enzymatic hydrolysis make the overall process of lignocellulosic conversion into biofuels less economical than available fossil fuels. Lignocellulose conversions carried out at ≤ 50 °C have several limitations. Therefore, this review focuses on the importance of thermophilic bacteria and thermostable enzymes to overcome the limitations of existing lignocellulosic biomass conversion processes. The influence of high temperatures on various existing lignocellulose conversion processes and those that are under development, including separate hydrolysis and fermentation, simultaneous saccharification and fermentation, and extremophilic consolidated bioprocess are also discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Initiating decision-making conversations in palliative care: an ethnographic discourse analysis.

PubMed

Bélanger, Emmanuelle; Rodríguez, Charo; Groleau, Danielle; Légaré, France; Macdonald, Mary Ellen; Marchand, Robert

2014-01-01

Conversations about end-of-life care remain challenging for health care providers. The tendency to delay conversations about care options represents a barrier that impedes the ability of terminally-ill patients to participate in decision-making. Family physicians with a palliative care practice are often responsible for discussing end-of-life care preferences with patients, yet there is a paucity of research directly observing these interactions. In this study, we sought to explore how patients and family physicians initiated decision-making conversations in the context of a community hospital-based palliative care service. This qualitative study combined discourse analysis with ethnographic methods. The field research lasted one year, and data were generated through participant observation and audio-recordings of consultations. A total of 101 consultations were observed longitudinally between 18 patients, 6 family physicians and 2 pivot nurses. Data analysis consisted in exploring the different types of discourses initiating decision-making conversations and how these discourses were affected by the organizational context in which they took place. The organization of care had an impact on decision-making conversations. The timing and origin of referrals to palliative care shaped whether patients were still able to participate in decision-making, and the decisions that remained to be made. The type of decisions to be made also shaped how conversations were initiated. Family physicians introduced decision-making conversations about issues needing immediate attention, such as symptom management, by directly addressing or eliciting patients' complaints. When decisions involved discussing impending death, decision-making conversations were initiated either indirectly, by prompting the patients to express their understanding of the disease and its progression, or directly, by providing a justification for broaching a difficult topic. Decision-making conversations and the initiation thereof were framed by the organization of care and the referral process prior to initial encounters. While symptom management was taken for granted as part of health care professionals' expected role, engaging in decisions regarding preparation for death implicitly remained under patients' control. This work makes important clinical contributions by exposing the rhetorical function of family physicians' discourse when introducing palliative care decisions.

Comparison of oil refining and biodiesel production process between screw press and n-hexane techniques from beauty leaf feedstock

NASA Astrophysics Data System (ADS)

Bhuiya, M. M. K.; Rasul, M. G.; Khan, M. M. K.; Ashwath, N.

2016-07-01

The Beauty Leaf Tree (Callophylum inophyllum) is regarded as an alternative source of energy to produce 2nd generation biodiesel due to its potentiality as well as high oil yield content in the seed kernels. The treating process is indispensable during the biodiesel production process because it can augment the yield as well as quality of the product. Oil extracted from both mechanical screw press and solvent extraction using n-hexane was refined. Five replications each of 25 gm of crude oil for screw press and five replications each of 25 gm of crude oil for n-hexane were selected for refining as well as biodiesel conversion processes. The oil refining processes consists of degumming, neutralization as well as dewaxing. The degumming, neutralization and dewaxing processes were performed to remove all the gums (phosphorous-based compounds), free fatty acids, and waxes from the fresh crude oil before the biodiesel conversion process carried out, respectively. The results indicated that up to 73% and 81% of mass conversion efficiency of the refined oil in the screw press and n-hexane refining processes were obtained, respectively. It was also found that up to 88% and 90% of biodiesel were yielded in terms of mass conversion efficiency in the transesterification process for the screw press and n-hexane techniques, respectively. While the entire processes (refining and transesterification) were considered, the conversion of beauty leaf tree (BLT) refined oil into biodiesel was yielded up to 65% and 73% of mass conversion efficiency for the screw press and n-hexane techniques, respectively. Physico-chemical properties of crude and refined oil, and biodiesel were characterized according to the ASTM standards. Overall, BLT has the potential to contribute as an alternative energy source because of high mass conversion efficiency.

24 CFR 972.109 - Conversion of developments.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Conversion of developments. 972.109... DEVELOPMENT CONVERSION OF PUBLIC HOUSING TO TENANT-BASED ASSISTANCE Required Conversion of Public Housing Developments Required Conversion Process § 972.109 Conversion of developments. (a)(1) The PHA may proceed to...

24 CFR 972.109 - Conversion of developments.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Conversion of developments. 972.109... DEVELOPMENT CONVERSION OF PUBLIC HOUSING TO TENANT-BASED ASSISTANCE Required Conversion of Public Housing Developments Required Conversion Process § 972.109 Conversion of developments. (a)(1) The PHA may proceed to...

Issues in Retrospective Conversion for a Small Special Collection: A Case Study.

ERIC Educational Resources Information Center

Hieb, Fern

1997-01-01

Small special collections present unique problems for retrospective conversion of catalogs to machine-readable form. Examines retrospective conversion using the Moravian Music Foundation as a case study. Discusses advantages to automation, options for conversion process, quantifying conversion effort, costs, in-house conversion, national standards…

Hydrogen Production via a High-Efficiency Low-Temperature Reformer

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

Paul KT Liu; Theo T. Tsotsis

2006-05-31

Fuel cells are promoted by the US government as a viable alternative for clean and efficient energy generation. It is anticipated that the fuel cell market will rise if the key technical barriers can be overcome. One of them is certainly fuel processing and purification. Existing fuel reforming processes are energy intensive, extremely complicated and capital intensive; these disadvantages handicap the scale-down of existing reforming process, targeting distributed or on-board/stationary hydrogen production applications. Our project involves the bench-scale demonstration of a high-efficiency low-temperature steam reforming process. Hydrogen production can be operated at 350 to 400ºC with our invention, as opposedmore » to >800ºC of existing reforming. In addition, our proposed process improves the start-up deficiency of conventional reforming due to its low temperature operation. The objective of this project is to demonstrate the invented process concept via a bench scale unit and verify mathematical simulation for future process optimization study. Under this project, we have performed the experimental work to determine the adsorption isotherm, reaction kinetics, and membrane permeances required to perform the process simulation based upon the mathematical model developed by us. A ceramic membrane coated with palladium thin film fabricated by us was employed in this study. The adsorption isotherm for a selected hydrotalcite adsorbent was determined experimentally. Further, the capacity loss under cyclic adsorption/desorption was confirmed to be negligible. Finally a commercial steam reforming catalyst was used to produce the reaction kinetic parameters required for the proposed operating condition. With these input parameters, a mathematical simulation was performed to predict the performance of the invented process. According to our simulation, our invented hybrid process can deliver 35 to 55% methane conversion, in comparison with the 12 and 18-21% conversion of the packed bed and an adsorptive reactor respectively. In addition CO contamination with <10 to 120 ppm is predicted for the invented process depending upon the cycle time for the PSA type operation. In comparison, the adsorption reactor can also deliver a similar CO contaminant at the low end; however, its high end reaches as high as 300 ppm based upon the simulation of our proposed operating condition. Our experimental results for the packed bed and the membrane reactor deliver 12 and 18% conversion at 400°C, approaching the conversion by the mathematical simulation. Due to the time constraint, the experimental study on the conversion of the invented process has not been complete. However, our in-house study using a similar process concept for the water gas shift reaction has demonstrated the reliability of our mathematical simulation for the invented process. In summary, we are confident that the invented process can deliver efficiently high purity hydrogen at a low temperature (~400°C). According to our projection, the invented process can further achieve 5% energy savings and ~50% capital savings over conventional reforming for fuel cell applications. The pollution abatement potential associated with the implementation of fuel cells, including the elimination of nitrogen oxides and CO, and the reduction in volatile organics and CO2, can thus be realized with the implementation of this invented process. The projected total market size for equipment sale for the proposed process in US is $1.5 billion annually.« less

Rectenna session: Micro aspects

NASA Technical Reports Server (NTRS)

Gutmann, R. J.

1980-01-01

Two micro aspects of rectenna design are discussed: evaluation of the degradation in net rectenna RF to DC conversion efficiency due to power density variations across the rectenna (power combining analysis) and design of Yagi-Uda receiving elements to reduce rectenna cost by decreasing the number of conversion circuits (directional receiving elements). The first of these involves resolving a fundamental question of efficiency potential with a rectenna, while the second involves a design modification with a large potential cost saving.

Piezoelectric energy harvesting computer controlled test bench

NASA Astrophysics Data System (ADS)

Vázquez-Rodriguez, M.; Jiménez, F. J.; de Frutos, J.; Alonso, D.

2016-09-01

In this paper a new computer controlled (C.C.) laboratory test bench is presented. The patented test bench is made up of a C.C. road traffic simulator, C.C. electronic hardware involved in automating measurements, and test bench control software interface programmed in LabVIEW™. Our research is focused on characterizing electronic energy harvesting piezoelectric-based elements in road traffic environments to extract (or "harvest") maximum power. In mechanical to electrical energy conversion, mechanical impacts or vibrational behavior are commonly used, and several major problems need to be solved to perform optimal harvesting systems including, but no limited to, primary energy source modeling, energy conversion, and energy storage. It is described a novel C.C. test bench that obtains, in an accurate and automatized process, a generalized linear equivalent electrical model of piezoelectric elements and piezoelectric based energy store harvesting circuits in order to scale energy generation with multiple devices integrated in different topologies.

Printable enzyme-embedded materials for methane to methanol conversion

DOE PAGES

Blanchette, Craig D.; Knipe, Jennifer M.; Stolaroff, Joshuah K.; ...

2016-06-15

An industrial process for the selective activation of methane under mild conditions would be highly valuable for controlling emissions to the environment and for utilizing vast new sources of natural gas. The only selective catalysts for methane activation and conversion to methanol under mild conditions are methane monooxygenases (MMOs) found in methanotrophic bacteria; however, these enzymes are not amenable to standard enzyme immobilization approaches. Using particulate methane monooxygenase (pMMO), we create a biocatalytic polymer material that converts methane to methanol. We demonstrate embedding the material within a silicone lattice to create mechanically robust, gas-permeable membranes, and direct printing of micron-scalemore » structures with controlled geometry. Remarkably, the enzymes retain up to 100% activity in the polymer construct. The printed enzyme-embedded polymer motif is highly flexible for future development and should be useful in a wide range of applications, especially those involving gas–liquid reactions.« less

Printable enzyme-embedded materials for methane to methanol conversion

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

Blanchette, Craig D.; Knipe, Jennifer M.; Stolaroff, Joshuah K.

An industrial process for the selective activation of methane under mild conditions would be highly valuable for controlling emissions to the environment and for utilizing vast new sources of natural gas. The only selective catalysts for methane activation and conversion to methanol under mild conditions are methane monooxygenases (MMOs) found in methanotrophic bacteria; however, these enzymes are not amenable to standard enzyme immobilization approaches. Using particulate methane monooxygenase (pMMO), we create a biocatalytic polymer material that converts methane to methanol. We demonstrate embedding the material within a silicone lattice to create mechanically robust, gas-permeable membranes, and direct printing of micron-scalemore » structures with controlled geometry. Remarkably, the enzymes retain up to 100% activity in the polymer construct. The printed enzyme-embedded polymer motif is highly flexible for future development and should be useful in a wide range of applications, especially those involving gas–liquid reactions.« less

Piezoelectric energy harvesting computer controlled test bench.

PubMed

Vázquez-Rodriguez, M; Jiménez, F J; de Frutos, J; Alonso, D

2016-09-01

In this paper a new computer controlled (C.C.) laboratory test bench is presented. The patented test bench is made up of a C.C. road traffic simulator, C.C. electronic hardware involved in automating measurements, and test bench control software interface programmed in LabVIEW™. Our research is focused on characterizing electronic energy harvesting piezoelectric-based elements in road traffic environments to extract (or "harvest") maximum power. In mechanical to electrical energy conversion, mechanical impacts or vibrational behavior are commonly used, and several major problems need to be solved to perform optimal harvesting systems including, but no limited to, primary energy source modeling, energy conversion, and energy storage. It is described a novel C.C. test bench that obtains, in an accurate and automatized process, a generalized linear equivalent electrical model of piezoelectric elements and piezoelectric based energy store harvesting circuits in order to scale energy generation with multiple devices integrated in different topologies.

Genetic variation of the Borrelia burgdorferi gene vlsE involves cassette-specific, segmental gene conversion.

PubMed

Zhang, J R; Norris, S J

1998-08-01

The Lyme disease spirochete Borrelia burgdorferi possesses 15 silent vls cassettes and a vls expression site (vlsE) encoding a surface-exposed lipoprotein. Segments of the silent vls cassettes have been shown to recombine with the vlsE cassette region in the mammalian host, resulting in combinatorial antigenic variation. Despite promiscuous recombination within the vlsE cassette region, the 5' and 3' coding sequences of vlsE that flank the cassette region are not subject to sequence variation during these recombination events. The segments of the silent vls cassettes recombine in the vlsE cassette region through a unidirectional process such that the sequence and organization of the silent vls loci are not affected. As a result of recombination, the previously expressed segments are replaced by incoming segments and apparently degraded. These results provide evidence for a gene conversion mechanism in VlsE antigenic variation.

Printable enzyme-embedded materials for methane to methanol conversion

PubMed Central

Blanchette, Craig D.; Knipe, Jennifer M.; Stolaroff, Joshuah K.; DeOtte, Joshua R.; Oakdale, James S.; Maiti, Amitesh; Lenhardt, Jeremy M.; Sirajuddin, Sarah; Rosenzweig, Amy C.; Baker, Sarah E.

2016-01-01

An industrial process for the selective activation of methane under mild conditions would be highly valuable for controlling emissions to the environment and for utilizing vast new sources of natural gas. The only selective catalysts for methane activation and conversion to methanol under mild conditions are methane monooxygenases (MMOs) found in methanotrophic bacteria; however, these enzymes are not amenable to standard enzyme immobilization approaches. Using particulate methane monooxygenase (pMMO), we create a biocatalytic polymer material that converts methane to methanol. We demonstrate embedding the material within a silicone lattice to create mechanically robust, gas-permeable membranes, and direct printing of micron-scale structures with controlled geometry. Remarkably, the enzymes retain up to 100% activity in the polymer construct. The printed enzyme-embedded polymer motif is highly flexible for future development and should be useful in a wide range of applications, especially those involving gas–liquid reactions. PMID:27301270

Mathematical modeling of elementary trapping-reduction processes in positron annihilation lifetime spectroscopy: methodology of Ps-to-positron trapping conversion

NASA Astrophysics Data System (ADS)

Shpotyuk, Ya; Cebulski, J.; Ingram, A.; Shpotyuk, O.

2017-12-01

Methodological possibilities of positron annihilation lifetime (PAL) spectroscopy in application to nanostructurized substances treated within three-term fitting procedure are reconsidered to parameterize their atomic-deficient structural arrangement. In contrast to conventional three-term fitting analysis of the detected PAL spectra based on admixed positron trapping and positronium (Ps) decaying, the nanostructurization due to guest nanoparticles embedded in host matrix is considered as producing modified trapping, which involves conversion between these channels. The developed approach referred to as x3-x2-coupling decomposition algorithm allows estimation free volumes of interfacial voids responsible for positron trapping and bulk lifetimes in nanoparticle-embedded substances. This methodology is validated using experimental data of Chakraverty et al. [Phys. Rev. B71 (2005) 024115] on PAL study of composites formed by guest NiFe2O4 nanocrystals grown in host SiO2 matrix.

End-of-life conversations and care: an asset-based model for community engagement.

PubMed

Matthiesen, Mary; Froggatt, Katherine; Owen, Elaine; Ashton, John R

2014-09-01

Public awareness work regarding palliative and end-of-life care is increasingly promoted within national strategies for palliative care. Different approaches to undertaking this work are being used, often based upon broader educational principles, but little is known about how to undertake such initiatives in a way that equally engages both the health and social care sector and the local communities. An asset-based community engagement approach has been developed that facilitates community-led awareness initiatives concerning end-of-life conversations and care by identifying and connecting existing skills and expertise. (1) To describe the processes and features of an asset-based community engagement approach that facilitates community-led awareness initiatives with a focus on end-of-life conversations and care; and (2) to identify key community-identified priorities for sustainable community engagement processes. An asset-based model of community engagement specific to end-of-life issues using a four-step process is described (getting started, coming together, action planning and implementation). The use of this approach, in two regional community engagement programmes, based across rural and urban communities in the northwest of England, is described. The assets identified in the facilitated community engagement process encompassed people's talents and skills, community groups and networks, government and non-government agencies, physical and economic assets and community values and stories. Five priority areas were addressed to ensure active community engagement work: information, outreach, education, leadership and sustainability. A facilitated, asset-based approach of community engagement for end-of-life conversations and care can catalyse community-led awareness initiatives. This occurs through the involvement of community and local health and social care organisations as co-creators of this change across multiple sectors in a sustainable way. This approach provides a framework for other communities seeking to engage with public awareness in end-of-life issues. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Service user involvement in research may lead to contrary rather than collaborative accounts: findings from a qualitative palliative care study.

PubMed

Forbat, Liz; Hubbard, Gill

2016-04-01

The aim of this study was to explore what data emerge when former carergivers (co-researchers) are trained to interview current care-givers about their experiences. Despite a trend of involving service users in conducting research interviews, there have been few examinations of how and whether a common service user identity has an impact on the data generated. Four co-researchers were recruited, trained and supported to conduct qualitative interviews with 11 current carers of people receiving palliative services. Conversation analysis was used to examine the conversational characteristics of the research interviews. Data were collected in 2010-2011. Conversation analysis identified that interactional difficulties were evident across the data. When co-researchers talked about their own experiences as carers, interviewees frequently changed the topic of conversation, thereby closing-down opportunities for further disclosure or elaboration from the interviewee about the original topic. Conversation analysis identifies how caregiving identities are co-constructed and points where there is agreement and disagreement in the co-construction. © 2015 John Wiley & Sons Ltd.

Students' development of models of magnetic materials, patterns of group activity, and social norms in a physics classroom

NASA Astrophysics Data System (ADS)

Johnson, Andrew P.

1999-11-01

This dissertation is a study of students' model development processes in a physical science course for preservice elementary teachers. It details the models of magnetic materials developed and used by students during a unit on static electricity and magnetism. In this inquiry-based course, the class developed and formally accepted a model, in the form of diagrams and descriptions, that is very similar to the accepted magnetic domains model. They did this without textbooks or lectures on magnetism. Before adopting this model, however, most groups in the class temporarily used models involving opposite charges at the two ends of magnetized nails. How did the students do it? The explanation involves detailed study of the groups' interactions and use of structure in the classroom environment. This dissertation uses two theoretical frameworks to analyze interactions. It applies Yackel and Cobb's (1996) concepts of classroom social norms to characterize aspects of the classroom participation structure which affected groups' construction and declaration of models. It also applies distributed cognition ideas to analyze the sense-making conversations that small groups had when constructing group responses. This research found that conversations in one small group could be characterized into sixteen categories. Important categories included "extending ideas" which involved gradual deepening and elaboration of the group's understanding of their model(s), and "joint typing", an interactive process by which group members collaborated on typed statements or group diagrams and simultaneously developed common language for communicating their ideas to each other. Some of these categories of activity were closely connected to computer use. Also, four classroom norms are described. One small group social classroom norm involved group members developing a "common ground" consisting of agreed-upon group statements. Three sociophysics norms which characterize the whole class interactions as well as those of the small group involved a distinction between generalizations of phenomena and theoretical statements, class criteria for accepting evidence, and the obligation for each group to have a model of magnetic materials that they could support with acceptable evidence.

Metal hydrides: an innovative and challenging conversion reaction anode for lithium-ion batteries

PubMed Central

Oumellal, Yassine; Bonnet, Jean-Pierre

2015-01-01

Summary The state of the art of conversion reactions of metal hydrides (MH) with lithium is presented and discussed in this review with regard to the use of these hydrides as anode materials for lithium-ion batteries. A focus on the gravimetric and volumetric storage capacities for different examples from binary, ternary and complex hydrides is presented, with a comparison between thermodynamic prediction and experimental results. MgH2 constitutes one of the most attractive metal hydrides with a reversible capacity of 1480 mA·h·g−1 at a suitable potential (0.5 V vs Li+/Li0) and the lowest electrode polarization (<0.2 V) for conversion materials. Conversion process reaction mechanisms with lithium are subsequently detailed for MgH2, TiH2, complex hydrides Mg2MHx and other Mg-based hydrides. The reversible conversion reaction mechanism of MgH2, which is lithium-controlled, can be extended to others hydrides as: MHx + xLi+ + xe− in equilibrium with M + xLiH. Other reaction paths—involving solid solutions, metastable distorted phases, and phases with low hydrogen content—were recently reported for TiH2 and Mg2FeH6, Mg2CoH5 and Mg2NiH4. The importance of fundamental aspects to overcome technological difficulties is discussed with a focus on conversion reaction limitations in the case of MgH2. The influence of MgH2 particle size, mechanical grinding, hydrogen sorption cycles, grinding with carbon, reactive milling under hydrogen, and metal and catalyst addition to the MgH2/carbon composite on kinetics improvement and reversibility is presented. Drastic technological improvement in order to the enhance conversion process efficiencies is needed for practical applications. The main goals are minimizing the impact of electrode volume variation during lithium extraction and overcoming the poor electronic conductivity of LiH. To use polymer binders to improve the cycle life of the hydride-based electrode and to synthesize nanoscale composite hydride can be helpful to address these drawbacks. The development of high-capacity hydride anodes should be inspired by the emergent nano-research prospects which share the knowledge of both hydrogen-storage and lithium-anode communities. PMID:26425434

Process for chemical reaction of amino acids and amides yielding selective conversion products

DOEpatents

Holladay, Jonathan E [Kennewick, WA

2006-05-23

The invention relates to processes for converting amino acids and amides to desirable conversion products including pyrrolidines, pyrrolidinones, and other N-substituted products. L-glutamic acid and L-pyroglutamic acid provide general reaction pathways to numerous and valuable selective conversion products with varied potential industrial uses.

Semantic trouble sources and their repair in conversations affected by Parkinson's disease

PubMed Central

Saldert, Charlotta; Ferm, Ulrika; Bloch, Steven

2014-01-01

Background It is known that dysarthria arising from Parkinson's disease may affect intelligibility in conversational interaction. Research has also shown that Parkinson's disease may affect cognition and cause word-retrieval difficulties and pragmatic problems in the use of language. However, it is not known whether or how these problems become manifest in everyday conversations or how conversation partners handle such problems. Aims To describe the pragmatic problems related to the use of words that occur in everyday conversational interaction in dyads including an individual with Parkinson's disease, and to explore how interactants in conversation handle the problems to re-establish mutual understanding. Methods & Procedures Twelve video-recorded everyday conversations involving three couples where one of the individuals had Parkinson's disease were included in the study. All instances of other-initiated repair following a contribution from the people with Parkinson's disease were analysed. Those instances involving a trouble source relating to the use of words were analysed with a qualitative interaction analysis based on the principles of conversation analysis. Outcomes & Results In 70% of the instances of other-initiated repair the trouble source could be related to the semantic content produced by the individual with Parkinson's disease. The problematic contributions were typically characterized by more or less explicit symptoms of word search or use of atypical wording. The conversation partners completed the repair work collaboratively, but typically the non-impaired individual made a rephrasing or provided a suggestion for what the intended meaning had been. Conclusions & Implications In clinical work with people with Parkinson's disease and their conversation partners it is important to establish what type of trouble sources occur in conversations in a specific dyad. It may often be necessary to look beyond intelligibility and into aspects of pragmatics to understand more fully the impact of Parkinson's disease on everyday conversational interaction. PMID:24934292

Another look at retroactive and proactive interference: a quantitative analysis of conversion processes.

PubMed

Blank, Hartmut

2005-02-01

Traditionally, the causes of interference phenomena were sought in "real" or "hard" memory processes such as unlearning, response competition, or inhibition, which serve to reduce the accessibility of target items. I propose an alternative approach which does not deny the influence of such processes but highlights a second, equally important, source of interference-the conversion (Tulving, 1983) of accessible memory information into memory performance. Conversion is conceived as a problem-solving-like activity in which the rememberer tries to find solutions to a memory task. Conversion-based interference effects are traced to different conversion processes in the experimental and control conditions of interference designs. I present a simple theoretical model that quantitatively predicts the resulting amount of interference. In two paired-associate learning experiments using two different types of memory tests, these predictions were corroborated. Relations of the present approach to traditional accounts of interference phenomena and implications for eyewitness testimony are discussed.

The Effect of Deposit Temperature on the Catalytic SO2-to-SO3 Conversion in a Copper Flash Smelting Heat Recovery Boiler

NASA Astrophysics Data System (ADS)

Lehmusto, Juho; Vainio, Emil; Laurén, Tor; Lindgren, Mari

2018-02-01

The aim of the work was to study the catalytic role of copper flash smelter deposit in the SO2-to-SO3 conversion. In addition, the effect of process gas temperature at 548 K to 1173 K (275 °C to 900 °C) on the amount of SO3 formed was addressed both in the absence and presence of genuine copper flash smelter deposit. The SO3 conversion rate changed as a function of process gas temperature, peaking at 1023 K (750 °C). A dramatic increase in the SO2-to-SO3 conversion was observed when process dust was present, clearly indicating that process dust catalyzes the SO2-to-SO3 conversion. Based on these results, the catalytic ability of the deposit may lead to sulfuric acid dew point corrosion.

Carbohydrates as indicators of biogeochemical processes

NASA Astrophysics Data System (ADS)

Lazareva, E. V.; Romankevich, E. A.

2012-05-01

A method is presented to study the carbohydrate composition of marine objects involved into sedimento- and diagenesis (plankton, particulate matter, benthos, and bottom sediments). The analysis of the carbohydrates is based upon the consecutive separation of their fractions with different solvents (water, alkali, and acid). The ratio of the carbohydrate fractions allows one to evaluate the lability of the carbohydrate complex. It is also usable as an indicator of the biogeochemical processes in the ocean, as well of the genesis and the degree of conversion of organic matter in the bottom sediments and nodules. The similarity in the monosaccharide composition is shown for dissolved organic matter and aqueous and alkaline fractions of seston and particulate matter.

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

Davis, R.; Tao, L.; Scarlata, C.

This report describes one potential conversion process to hydrocarbon products by way of catalytic conversion of lignocellulosic-derived hydrolysate. This model leverages expertise established over time in biomass deconstruction and process integration research at NREL, while adding in new technology areas for sugar purification and catalysis. The overarching process design converts biomass to die die diesel- and naphtha-range fuels using dilute-acid pretreatment, enzymatic saccharification, purifications, and catalytic conversion focused on deoxygenating and oligomerizing biomass hydrolysates.

Catalyst and process development for the H/sub 2/ preparation from future fuel cell feedstocks. Quarterly progress report, October 1, 1978-December 31, 1978

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

Yarrington, R M; Feins, I R; Hwang, H S

1979-01-01

The work done under this contract in the last quarter of 1978 was concerned with Phase I, which involved preliminary catalyst and process evaluation. The processes under study are hydrogen assisted steam reforming (HASR), catalytic partial oxidation (CPO), and autothermal steam reforming (ATR). Existing Engelhard test units were modified to carry out preliminary runs using the first two processes. Technical analysis to support work in this area consisted of heat and material balances constrained by equilibrium considerations. In a third task, the steam reforming of methanol to produce hydrogen was studied over two commercial low-temperature shift catalysts. Aging runs indicatedmore » good initial performance on both catalysts, but methanol conversion started to decline after a few hundred hours on stream.« less

Energy Conversion and Storage Program

NASA Astrophysics Data System (ADS)

Cairns, E. J.

1993-06-01

This report is the 1992 annual progress report for the Energy Conversion and Storage Program, a part of the Energy and Environment Division of the Lawrence Berkeley Laboratory. Work described falls into three broad areas: electrochemistry; chemical applications; and materials applications. The Energy Conversion and Storage Program applies principles of chemistry and materials science to solve problems in several areas: (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes and chemical species, and (5) study and application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis. Electrochemistry research aims to develop advanced power systems for electric vehicle and stationary energy storage applications. Chemical applications research includes topics such as separations, catalysis, fuels, and chemical analyses. Included in this program area are projects to develop improved, energy-efficient methods for processing product and waste streams from synfuel plants, coal gasifiers, and biomass conversion processes. Materials applications research includes evaluation of the properties of advanced materials, as well as development of novel preparation techniques. For example, techniques such as sputtering, laser ablation, and poised laser deposition are being used to produce high-temperature superconducting films.

Using Conversation MOPs in Natural Language Interfaces.

ERIC Educational Resources Information Center

Turner, Elise H.; Cullingford, Richard E.

1989-01-01

Explores a method of combining convention and intention by representing conversation structure with conversation MOPs (schematic structures that store conversation rules as generalized episodes associated with goals the episodes achieved). Discusses how conversation MOPs process the opening portion of a dialogue in an interactive advice-giving…

Boundary Conditions for Diffusion-Mediated Processes within Linear Nanopores: Exact Treatment of Coupling to an Equilibrated External Fluid

DOE PAGES

Garcia, Andres; Evans, James W.

2017-04-03

In this paper, we consider a variety of diffusion-mediated processes occurring within linear nanopores, but which involve coupling to an equilibrated external fluid through adsorption and desorption. By determining adsorption and desorption rates through a set of tailored simulations, and by exploiting a spatial Markov property of the models, we develop a formulation for performing efficient pore-only simulations of these processes. Coupling to the external fluid is described exactly through appropriate nontrivial boundary conditions at the pore openings. This formalism is applied to analyze the following: (i) tracer counter permeation (TCP) where different labeled particles adsorb into opposite ends ofmore » the pore and establish a nonequilibrium steady state; (ii) tracer exchange (TE) with exchange of differently labeled particles within and outside the pore; (iii) catalytic conversion reactions where a reactant in the external fluid adsorbs into the pore and converts to a product which may desorb. The TCP analysis also generates a position-dependent generalized tracer diffusion coefficient, the form of which controls behavior in the TE and catalytic conversion processes. We focus on the regime of single-file diffusion within the pore which produces the strongest correlations and largest deviations from mean-field type behavior. Finally, behavior is quantified precisely via kinetic Monte Carlo simulations but is also captured with appropriate analytic treatments.« less

Public health evolutionary biology of antimicrobial resistance: priorities for intervention

PubMed Central

Baquero, Fernando; Lanza, Val F; Cantón, Rafael; Coque, Teresa M

2015-01-01

The three main processes shaping the evolutionary ecology of antibiotic resistance (AbR) involve the emergence, invasion and occupation by antibiotic-resistant genes of significant environments for human health. The process of emergence in complex bacterial populations is a high-frequency, continuous swarming of ephemeral combinatory genetic and epigenetic explorations inside cells and among cells, populations and communities, expanding in different environments (migration), creating the stochastic variation required for evolutionary progress. Invasion refers to the process by which AbR significantly increases in frequency in a given (invaded) environment, led by external invaders local multiplication and spread, or by endogenous conversion. Conversion occurs because of the spread of AbR genes from an exogenous resistant clone into an established (endogenous) bacterial clone(s) colonizing the environment; and/or because of dissemination of particular resistant genetic variants that emerged within an endogenous clonal population. Occupation of a given environment by a resistant variant means a permanent establishment of this organism in this environment, even in the absence of antibiotic selection. Specific interventions on emergence influence invasion, those acting on invasion also influence occupation and interventions on occupation determine emergence. Such interventions should be simultaneously applied, as they are not simple solutions to the complex problem of AbR. PMID:25861381

Cognitive impairment at diagnosis predicts 10-year multiple sclerosis progression.

PubMed

Moccia, Marcello; Lanzillo, Roberta; Palladino, Raffaele; Chang, Kiara Chu-Mei; Costabile, Teresa; Russo, Cinzia; De Rosa, Anna; Carotenuto, Antonio; Saccà, Francesco; Maniscalco, Giorgia Teresa; Brescia Morra, Vincenzo

2016-04-01

Cognitive impairment occurs from the early phases of multiple sclerosis (MS), and more frequently affects secondary progressive (SP) subjects than relapsing-remitting (RR). To investigate relationships between cognitive dysfunctions in newly diagnosed RRMS, and long-term MS-related outcomes. The present 10-year retrospective longitudinal study included 155 RRMS subjects, tested with the Rao Brief Repeatable Battery at MS diagnosis. The reaching of Expanded Disability Status Scale (EDSS) 4.0, and the SP conversion were recorded. 67 subjects (43.2%) reached EDSS 4.0, and 34 subjects (21.9%) converted to SP during a follow-up period of 10.0±1.8 years. Subjects with cognitive impairment at diagnosis had a rate of reaching EDSS 4.0 more than three times greater (p<0.001; HR=3.183), and a rate of SP conversion more than two times greater, as compared to cognitively preserved subjects (p=0.008; HR=2.535). In particular, better scores in the Selective Reminding Test-Delayed Recall and in the Symbol Digit Modalities Test at baseline were associated with lower SP conversion rates during the follow-up period (p=0.018; HR=0.835; and p=0.001; HR=0.941, respectively). Cognitive impairment, with particular involvement of processing speed and memory, predicts disability progression and SP conversion in newly diagnosed RRMS, highlighting the importance of cognitive assessment from the beginning of MS. © The Author(s), 2015.

Involvement of Family Members and Professionals in Older Women's Post-Fall Decision Making.

PubMed

Bergeron, Caroline D; Hilfinger Messias, DeAnne K; Friedman, Daniela B; Spencer, S Melinda; Miller, Susan C

2018-03-01

This exploratory, descriptive study examined involvement of family members and professionals in older women's post-fall decision making. We conducted semistructured interviews with 17 older women who had recently fallen and 11 individuals these women identified as being engaged in their post-fall decision-making processes. Qualitative data analysis involved open and axial coding and development of themes. After experiencing a fall, these older women's openness to others' opinions and advice; their assessments of types and credibility of potential information sources; and the communication practices they established with these sources influenced how they accessed, accepted, or rejected information from family members and professionals. Increased awareness of the involvement of others in post-fall decision making could enhance communication with older women who fall. Developing and implementing practical strategies to help family members and professionals initiate and engage in conversations about falls and their consequences could lead to more open decision making and improved post-fall quality of life among older women.

Neural basis of bilingual language control.

PubMed

Calabria, Marco; Costa, Albert; Green, David W; Abutalebi, Jubin

2018-06-19

Acquiring and speaking a second language increases demand on the processes of language control for bilingual as compared to monolingual speakers. Language control for bilingual speakers involves the ability to keep the two languages separated to avoid interference and to select one language or the other in a given conversational context. This ability is what we refer with the term "bilingual language control" (BLC). It is now well established that the architecture of this complex system of language control encompasses brain networks involving cortical and subcortical structures, each responsible for different cognitive processes such as goal maintenance, conflict monitoring, interference suppression, and selective response inhibition. Furthermore, advances have been made in determining the overlap between the BLC and the nonlinguistic executive control networks, under the hypothesis that the BLC processes are just an instantiation of a more domain-general control system. Here, we review the current knowledge about the neural basis of these control systems. Results from brain imaging studies of healthy adults and on the performance of bilingual individuals with brain damage are discussed. © 2018 New York Academy of Sciences.

Potential insight for drug discovery from high fidelity receptor-mediated transduction mechanisms in insects

PubMed Central

Raffa, Robert B.; Raffa, Kenneth F.

2011-01-01

Introduction There is a pervasive and growing concern about the small number of new pharmaceutical agents. There are many proposed explanations for this trend that do not involve the drug-discovery process per se, but the discovery process itself has also come under scrutiny. If the current paradigms are indeed not working, where are novel ideas to come from? Perhaps it is time to look to novel sources. Areas covered The receptor-signaling and 2nd-messenger transduction processes present in insects are quite similar to those in mammals (involving G proteins, ion channels, etc.). However, a review of these systems reveals an unprecedented degree of high potency and receptor selectivity to an extent greater than that modeled in most current drug-discovery approaches. Expert opinion A better understanding of insect receptor pharmacology could stimulate novel theoretical and practical ideas in mammalian pharmacology (drug discovery) and, conversely, the application of pharmacology and medicinal chemistry principles could stimulate novel advances in entomology (safer and more targeted control of pest species). PMID:21984882

"So they are not alive?": Dementia, reality disjunctions and conversational strategies.

PubMed

Hydén, Lars-Christer; Samuelsson, Christina

2018-01-01

In some conversations involving persons with Alzheimer's disease, the participants may have to deal with the difficulty that they do not share a common ground in terms of not only who is alive or dead, but even more, who could possibly be alive. It is as if the participants face a reality disjunction. There are very few empirical studies of this difficulty in conversations involving persons with Alzheimer's disease or other kinds of dementia diagnoses. Often studies of confabulation have a focus on the behavior and experience of the healthy participants, but rarely on the interaction and the collaborative contributions made by the person with dementia. In the present article, we discuss various strategies used by all participants in an everyday conversation. The material consists of an hour long everyday conversation between a woman with Alzheimer's disease and two healthy participants (relatives). This conversation is analyzed by looking at the organization of the interaction with an emphasis on how the participants deal with instances of reality disjunctions. The result from the analysis demonstrates that both the healthy participants as well as the person with dementia together skillfully avoid the face threats posed by reality disjunctive contributions by not pursuing argumentative lines that in the end might jeopardize both the collaborative and the personal relations.

Comparative TEA for Indirect Liquefaction Pathways to Distillate-Range Fuels via Oxygenated Intermediates

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

Tan, Eric; Snowden-Swan, Lesley J.; Talmadge, Michael

This paper presents a comparative techno-economic analysis of five conversion pathways from biomass to gasoline-, jet-, and diesel-range hydrocarbons via indirect liquefaction with specific focus on pathways utilizing oxygenated intermediates (derived either via thermochemical or biochemical conversion steps). The four emerging pathways of interest are compared with one conventional pathway (Fischer-Tropsch) for the production of the hydrocarbon blendstocks. The processing steps of the four emerging pathways include: biomass-to-syngas via indirect gasification, gas cleanup, conversion of syngas to alcohols/oxygenates, followed by conversion of alcohols/oxygenates to hydrocarbon blendstocks via dehydration, oligomerization, and hydrogenation. We show that the emerging pathways via oxygenated intermediatesmore » have the potential to be cost competitive with the conventional Fischer-Tropsch process. The evaluated pathways and the benchmark process generally exhibit similar fuel yields and carbon conversion efficiencies. The resulting minimum fuel selling prices are comparable to the benchmark at approximately $3.60 per gallon-gasoline equivalent, with potential for two new pathways to be more economically competitive. Additionally, the coproduct values can play an important role in the economics of the processes with oxygenated intermediates derived via syngas fermentation. Major cost drivers for the integrated processes are tied to achievable fuel yields and conversion efficiency of the intermediate steps, i.e., the production of oxygenates/alcohols from syngas and the conversion of oxygenates/alcohols to hydrocarbon fuels.« less

[Management of patients with conversion disorder].

PubMed

Vermeulen, Marinus; Hoekstra, Jan; Kuipers-van Kooten, Mariëtte J; van der Linden, Els A M

2014-01-01

The symptoms of conversion disorder are not due to conscious simulation. There should be no doubt that the symptoms of conversion disorder are genuine, even if scans do not reveal any abnormalities. The management of patients with conversion disorder starts with an explanation of the diagnosis. The essence of this explanation is that patients first hear about what the diagnosis actually means and only after this about what they do not have. When explaining the diagnosis it is a good idea to use metaphors. The treatment of patients with conversion disorder is carried out together with a physical therapist. The collaboration of healthcare professionals who are involved in the treatment of a patient with conversion disorder should preferably be coordinated by the patient's general practitioner.

Photophysical and photochemical insights into the photodegradation of sulfapyridine in water: A joint experimental and theoretical study.

PubMed

Zhang, Heming; Wei, Xiaoxuan; Song, Xuedan; Shah, Shaheen; Chen, Jingwen; Liu, Jianhui; Hao, Ce; Chen, Zhongfang

2018-01-01

For organic pollutants, photodegradation, as a major abiotic elimination process and of great importance to the environmental fate and risk, involves rather complicated physical and chemical processes of excited molecules. Herein, we systematically studied the photophysical and photochemical processes of a widely used antibiotic, namely sulfapyridine. By means of density functional theory (DFT) computations, we examined the rate constants and the competition of both photophysical and photochemical processes, elucidated the photochemical reaction mechanism, calculated reaction quantum yield (Φ) based on both photophysical and photochemical processes, and subsequently estimated the photodegradation rate constant. We further conducted photolysis experiments to measure the photodegradation rate constant of sulfapyridine. Our computations showed that sulfapyridine at the lowest excited singlet state (S 1 ) mainly undergoes internal conversion to its ground state, and is difficult to transfer to the lowest excited triplet states (T 1 ) via intersystem crossing (ISC) and emit fluorescence. In T 1 state, compared with phosphorescence emission and ISC, chemical reaction is much easier to initiate. Encouragingly, the theoretically predicted photodegradation rate constant is close to the experimentally observed value, indicating that quantum chemistry computation is powerful enough to study photodegradation involving ultra-fast photophysical and photochemical processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Real Communication through Interview and Conversation Cards

ERIC Educational Resources Information Center

Bonin, Therese M.; Birckbichler, Diane W.

1975-01-01

A method for use in foreign language teaching which involves the use of conversation cards and interview cards is described. The method is intended to improve the ability of the student to communicate in the language and allow for greater individualization of instruction. (RM)

Proteomic changes during intestinal cell maturation in vivo

PubMed Central

Chang, Jinsook; Chance, Mark R.; Nicholas, Courtney; Ahmed, Naseem; Guilmeau, Sandra; Flandez, Marta; Wang, Donghai; Byun, Do-Sun; Nasser, Shannon; Albanese, Joseph M.; Corner, Georgia A.; Heerdt, Barbara G.; Wilson, Andrew J.; Augenlicht, Leonard H.; Mariadason, John M.

2008-01-01

Intestinal epithelial cells undergo progressive cell maturation as they migrate along the crypt-villus axis. To determine molecular signatures that define this process, proteins differentially expressed between the crypt and villus were identified by 2D-DIGE and MALDI-MS. Forty-six differentially expressed proteins were identified, several of which were validated by immunohistochemistry. Proteins upregulated in the villus were enriched for those involved in brush border assembly and lipid uptake, established features of differentiated intestinal epithelial cells. Multiple proteins involved in glycolysis were also upregulated in the villus, suggesting increased glycolysis is a feature of intestinal cell differentiation. Conversely, proteins involved in nucleotide metabolism, and protein processing and folding were increased in the crypt, consistent with functions associated with cell proliferation. Three novel paneth cell markers, AGR2, HSPA5 and RRBP1 were also identified. Notably, significant correlation was observed between overall proteomic changes and corresponding gene expression changes along the crypt-villus axis, indicating intestinal cell maturation is primarily regulated at the transcriptional level. This proteomic profiling analysis identified several novel proteins and functional processes differentially induced during intestinal cell maturation in vivo. Integration of proteomic, immunohistochemical, and parallel gene expression datasets demonstrate the coordinated manner in which intestinal cell maturation is regulated. PMID:18824147

The tumor microenvironment: An irreplaceable element of tumor budding and epithelial-mesenchymal transition-mediated cancer metastasis

PubMed Central

Li, Hui; Xu, Fangying; Li, Si; Zhong, Anjing; Meng, Xianwen; Lai, Maode

2016-01-01

ABSTRACT Tumor budding occurs at the invasive front of cancer; the tumor cells involved have metastatic and stemness features, indicating a poor prognosis. Tumor budding is partly responsible for cancer metastasis, and its initiation is based on the epithelial-mesenchymal transition (EMT) process. The EMT process involves the conversion of epithelial cells into migratory and invasive cells, and is a profound event in tumorigenesis. The EMT, associated with the formation of cancer stem cells (CSCs) and resistance to therapy, results from a combination of gene mutation, epigenetic regulation, and microenvironmental control. Tumor budding can be taken to represent the EMT in vivo. The EMT process is under the influence of the tumor microenvironment as well as tumor cells themselves. Here, we demonstrate that the tumor microenvironment dominates EMT development and impacts cancer metastasis, as well as promotes CSC formation and mediates drug resistance. In this review, we mainly discuss components of the microenvironment, such as the extracellular matrix (ECM), inflammatory cytokines, metabolic products, and hypoxia, that are involved in and impact on the acquisition of tumor-cell motility and dissemination, the EMT, metastatic tumor-cell formation, tumor budding and CSCs, and cancer metastasis, including subsequent chemo-resistance. From our point of view, the tumor microenvironment now constitutes a promising target for cancer therapy. PMID:26743180

The Conversion of Carboxylic Acids to Ketones: A Repeated Discovery

NASA Astrophysics Data System (ADS)

Nicholson, John W.; Wilson, Alan

2004-09-01

This article describes the history of the reaction converting carboxylic acids to ketones. The reaction has been rediscovered several times, yet has actually been known for centuries. The best known version of the process is the Dakin West reaction (1928), which applies to α-amino acids and also involves the simultaneous conversion of the amine group to amido functionality. Unlike other examples, this particular reaction has attracted a reasonable amount of attention and it appears to be better known than the conversion of simple carboxylic acids to ketones. However, this reaction was described as long ago as 1612, when Beguin published an account of it in his book, Tyrocinium Chymicum . Since then, many chemists have rediscovered the reaction, apparently independently. One of the earliest modern accounts was by W. H. Perkin, Sr., in 1886, who made various simple ketones by refluxing the appropriate carboxylic acids with base. However, this work has been largely ignored, including by his son, W. H. Perkin, Jr., who used a more complicated base-catalyzed ketonization to prepare small ring compounds in the early years of the 20th century. Other articles detailing the application of ketonization to organic acids are discussed, including our own work, which employed the process to crosslink carboxylated polymers for possible technical application in coatings. Despite its relative obscurity, the reaction was used by Woodward et al. in the total synthesis of strychnine, reported in 1963, and this is discussed in detail at the end of the article. See Featured Molecules .

Reliability Assessment Approach for Stirling Convertors and Generators

NASA Technical Reports Server (NTRS)

Shah, Ashwin R.; Schreiber, Jeffrey G.; Zampino, Edward; Best, Timothy

2004-01-01

Stirling power conversion is being considered for use in a Radioisotope Power System for deep-space science missions because it offers a multifold increase in the conversion efficiency of heat to electric power. Quantifying the reliability of a Radioisotope Power System that utilizes Stirling power conversion technology is important in developing and demonstrating the capability for long-term success. A description of the Stirling power convertor is provided, along with a discussion about some of the key components. Ongoing efforts to understand component life, design variables at the component and system levels, related sources, and the nature of uncertainties is discussed. The requirement for reliability also is discussed, and some of the critical areas of concern are identified. A section on the objectives of the performance model development and a computation of reliability is included to highlight the goals of this effort. Also, a viable physics-based reliability plan to model the design-level variable uncertainties at the component and system levels is outlined, and potential benefits are elucidated. The plan involves the interaction of different disciplines, maintaining the physical and probabilistic correlations at all the levels, and a verification process based on rational short-term tests. In addition, both top-down and bottom-up coherency were maintained to follow the physics-based design process and mission requirements. The outlined reliability assessment approach provides guidelines to improve the design and identifies governing variables to achieve high reliability in the Stirling Radioisotope Generator design.

One-Pot Conversion of Carbohydrates into Furan Derivatives via Furfural and 5-Hydroxylmethylfurfural as Intermediates.

PubMed

Liu, Bing; Zhang, Zehui

2016-08-23

Recently, there has been growing interest in the transformation of renewable biomass into value-added fuels and chemicals. The catalytic conversion of naturally abundant carbohydrates can generate two-important furan chemicals: 5-hydroxymethylfurfural (HMF) from C6 carbohydrates and furfural from C5 carbohydrates. Both HMF and furfural have received great interest as precursors in the synthesis of commodity chemicals and liquid fuels. In recent years, a trend has emerged to integrate sequential catalytic processes involving multistep reactions for the direct one-pot transformation of carbohydrates into the aimed fuels and chemicals. One-pot reactions have remarkably unique and environmentally friendly benefits, including the fact that isolation and purification of intermediate compounds can be avoided. Herein, the present article aims to review recent advances in the one-pot conversion of carbohydrates into furan derivatives via furfural and HMF as intermediates. Special attention will be paid to the catalytic systems, mechanistic insight, reaction pathways, and catalyst stability. It is expected that this review will guide researchers to develop effective catalytic systems for the one-pot transformation of carbohydrates into furan derivatives. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The development of malaria parasites in the mosquito midgut

PubMed Central

Bennink, Sandra; Kiesow, Meike J.

2016-01-01

Summary The mosquito midgut stages of malaria parasites are crucial for establishing an infection in the insect vector and to thus ensure further spread of the pathogen. Parasite development in the midgut starts with the activation of the intraerythrocytic gametocytes immediately after take‐up and ends with traversal of the midgut epithelium by the invasive ookinetes less than 24 h later. During this time period, the plasmodia undergo two processes of stage conversion, from gametocytes to gametes and from zygotes to ookinetes, both accompanied by dramatic morphological changes. Further, gamete formation requires parasite egress from the enveloping erythrocytes, rendering them vulnerable to the aggressive factors of the insect gut, like components of the human blood meal. The mosquito midgut stages of malaria parasites are unprecedented objects to study a variety of cell biological aspects, including signal perception, cell conversion, parasite/host co‐adaptation and immune evasion. This review highlights recent insights into the molecules involved in gametocyte activation and gamete formation as well as in zygote‐to‐ookinete conversion and ookinete midgut exit; it further discusses factors that can harm the extracellular midgut stages as well as the measures of the parasites to protect themselves from any damage. PMID:27111866

Goal setting dynamics that facilitate or impede a client-centered approach.

PubMed

Kessler, Dorothy; Walker, Ian; Sauvé-Schenk, Katrine; Egan, Mary

2018-04-19

Client-centred goal setting is central to the process of enabling occupation. Yet, there are multiple barriers to incorporating client-centred goal setting in practice. We sought to determine what might facilitate or impede the formation of client-centred goals in a context highly supportive of client-centred goal setting Methods: We used conversational analysis to examine goal-setting conversations that took place during a pilot trial of Occupational Performance Coaching for stroke survivors. Twelve goal-setting sessions were purposively selected, transcribed, and analyzed according to conventions for conversation analysis. Two main types of interactions were observed: introductory actions and goal selection actions. Introductory actions set the context for goal setting and involved sharing information and seeking clarification related to goal requirements and clients' occupational performance competencies. Goal selection actions were a series of interactions whereby the goals were explored, endorsed or dropped. Client-centred occupational performance goals may be facilitated through placing goal-setting in the context of life changes and lifelong development of goals, and through listening to clients' stories. Therapists may improve consistency in adoption of client-suggested goals through clarifying meaning attached to goals and being attuned to power dynamics and underlying values and beliefs around risk and goal attainability.

Conversion of one cell type into another: implications for understanding organ development, pathogenesis of cancer and generating cells for therapy.

PubMed

Corbett, James L; Tosh, David

2014-06-01

Metaplasia is the irreversible conversion of one differentiated cell or tissue type into another. Metaplasia usually occurs in tissues that undergo regeneration, and may, in a pathological context, predispose to an increased risk of disease. Studying the conditions leading to the development of metaplasia is therefore of significant clinical interest. In contrast, transdifferentiation (or cellular reprogramming) is a subset of metaplasia that describes the permanent conversion of one differentiated cell type into another, and generally occurs between cells that arise from neighbouring regions of the same germ layer. Transdifferentiation, although rare, has been shown to occur in Nature. New insights into the signalling pathways involved in normal tissue development may be obtained by investigating the cellular and molecular mechanisms in metaplasia and transdifferentiation, and additional identification of key molecular regulators in transdifferentiation and metaplasia could provide new targets for therapeutic treatment of diseases such as cancer, as well as generating cells for transplantation into patients with degenerative disorders. In the present review, we focus on the transdifferentiation of pancreatic cells into hepatocyte-like cells, the development of Barrett's metaplasia in the oesophagus, and the cellular and molecular mechanisms underlying both processes.

Single-tube analysis of DNA methylation with silica superparamagnetic beads.

PubMed

Bailey, Vasudev J; Zhang, Yi; Keeley, Brian P; Yin, Chao; Pelosky, Kristen L; Brock, Malcolm; Baylin, Stephen B; Herman, James G; Wang, Tza-Huei

2010-06-01

DNA promoter methylation is a signature for the silencing of tumor suppressor genes. Most widely used methods to detect DNA methylation involve 3 separate, independent processes: DNA extraction, bisulfite conversion, and methylation detection via a PCR method, such as methylation-specific PCR (MSP). This method includes many disconnected steps with associated losses of material, potentially reducing the analytical sensitivity required for analysis of challenging clinical samples. Methylation on beads (MOB) is a new technique that integrates DNA extraction, bisulfite conversion, and PCR in a single tube via the use of silica superparamagnetic beads (SSBs) as a common DNA carrier for facilitating cell debris removal and buffer exchange throughout the entire process. In addition, PCR buffer is used to directly elute bisulfite-treated DNA from SSBs for subsequent target amplifications. The diagnostic sensitivity of MOB was evaluated by methylation analysis of the CDKN2A [cyclin-dependent kinase inhibitor 2A (melanoma, p16, inhibits CDK4); also known as p16(INK4a)] promoter in serum DNA of lung cancer patients and compared with that of conventional methods. Methylation analysis consisting of DNA extraction followed by bisulfite conversion and MSP was successfully carried out within 9 h in a single tube. The median pre-PCR DNA yield was 6.61-fold higher with the MOB technique than with conventional techniques. Furthermore, MOB increased the diagnostic sensitivity in our analysis of the CDKN2A promoter in patient serum by successfully detecting methylation in 74% of cancer patients, vs the 45% detection rate obtained with conventional techniques. The MOB technique successfully combined 3 processes into a single tube, thereby allowing ease in handling and an increased detection throughput. The increased pre-PCR yield in MOB allowed efficient, diagnostically sensitive methylation detection.

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

Fitzpatrick, Stephen W.

This project involved a three-year program managed by BioMetics, Inc. (Waltham, MA) to demonstrate the commercial feasibility of Biofine thermochemical process technology for conversion of cellulose-containing wastes or renewable materials into levulinic acid, a versatile platform chemical. The program, commencing in October 1995, involved the design, procurement, construction and operation of a plant utilizing the Biofine process to convert 1 dry ton per day of paper sludge waste. The plant was successfully designed, constructed, and commissioned in 1997. It was operated for a period of one year on paper sludge from a variety of source paper mills to collect datamore » to verify the design for a commercial scale plant. Operational results were obtained for four different feedstock varieties. Stable, continuous operation was achieved for two of the feedstocks. Continuous operation of the plant at demonstration scale provided the opportunity for process optimization, development of operational protocols, operator training and identification of suitable materials of construction for scale up to commercial operation . Separated fiber from municipal waster was also successfully processed. The project team consisted of BioMetics Inc., Great Lakes Chemical Corporation (West Lafayette, IN), and New York State Energy Research and Development Authority (Albany, NY).« less

Memory for conversation and the development of common ground.

PubMed

McKinley, Geoffrey L; Brown-Schmidt, Sarah; Benjamin, Aaron S

2017-11-01

Efficient conversation is guided by the mutual knowledge, or common ground, that interlocutors form as a conversation progresses. Characterized from the perspective of commonly used measures of memory, efficient conversation should be closely associated with item memory-what was said-and context memory-who said what to whom. However, few studies have explicitly probed memory to evaluate what type of information is maintained following a communicative exchange. The current study examined how item and context memory relate to the development of common ground over the course of a conversation, and how these forms of memory vary as a function of one's role in a conversation as speaker or listener. The process of developing common ground was positively related to both item and context memory. In addition, content that was spoken was remembered better than content that was heard. Our findings illustrate how memory assessments can complement language measures by revealing the impact that basic conversational processes have on memory for what has been discussed. By taking this approach, we show that not only does the process of forming common ground facilitate communication in the present, but it also promotes an enduring record of that event, facilitating conversation into the future.

Strong converse theorems using Rényi entropies

NASA Astrophysics Data System (ADS)

Leditzky, Felix; Wilde, Mark M.; Datta, Nilanjana

2016-08-01

We use a Rényi entropy method to prove strong converse theorems for certain information-theoretic tasks which involve local operations and quantum (or classical) communication between two parties. These include state redistribution, coherent state merging, quantum state splitting, measurement compression with quantum side information, randomness extraction against quantum side information, and data compression with quantum side information. The method we employ in proving these results extends ideas developed by Sharma [preprint arXiv:1404.5940 [quant-ph] (2014)], which he used to give a new proof of the strong converse theorem for state merging. For state redistribution, we prove the strong converse property for the boundary of the entire achievable rate region in the (e, q)-plane, where e and q denote the entanglement cost and quantum communication cost, respectively. In the case of measurement compression with quantum side information, we prove a strong converse theorem for the classical communication cost, which is a new result extending the previously known weak converse. For the remaining tasks, we provide new proofs for strong converse theorems previously established using smooth entropies. For each task, we obtain the strong converse theorem from explicit bounds on the figure of merit of the task in terms of a Rényi generalization of the optimal rate. Hence, we identify candidates for the strong converse exponents for each task discussed in this paper. To prove our results, we establish various new entropic inequalities, which might be of independent interest. These involve conditional entropies and mutual information derived from the sandwiched Rényi divergence. In particular, we obtain novel bounds relating these quantities, as well as the Rényi conditional mutual information, to the fidelity of two quantum states.

Strong converse theorems using Rényi entropies

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

Leditzky, Felix; Datta, Nilanjana; Wilde, Mark M.

We use a Rényi entropy method to prove strong converse theorems for certain information-theoretic tasks which involve local operations and quantum (or classical) communication between two parties. These include state redistribution, coherent state merging, quantum state splitting, measurement compression with quantum side information, randomness extraction against quantum side information, and data compression with quantum side information. The method we employ in proving these results extends ideas developed by Sharma [preprint http://arxiv.org/abs/1404.5940 [quant-ph] (2014)], which he used to give a new proof of the strong converse theorem for state merging. For state redistribution, we prove the strong converse property for themore » boundary of the entire achievable rate region in the (e, q)-plane, where e and q denote the entanglement cost and quantum communication cost, respectively. In the case of measurement compression with quantum side information, we prove a strong converse theorem for the classical communication cost, which is a new result extending the previously known weak converse. For the remaining tasks, we provide new proofs for strong converse theorems previously established using smooth entropies. For each task, we obtain the strong converse theorem from explicit bounds on the figure of merit of the task in terms of a Rényi generalization of the optimal rate. Hence, we identify candidates for the strong converse exponents for each task discussed in this paper. To prove our results, we establish various new entropic inequalities, which might be of independent interest. These involve conditional entropies and mutual information derived from the sandwiched Rényi divergence. In particular, we obtain novel bounds relating these quantities, as well as the Rényi conditional mutual information, to the fidelity of two quantum states.« less

Downregulation of Ras C-terminal processing by JNK inhibition

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

Mouri, Wataru; Department of Neurosurgery, Yamagata University School of Medicine, Yamagata 990-9585; Biology Division, National Cancer Center Research Institute, Tokyo 104-0045

2008-06-27

After translation, Ras proteins undergo a series of modifications at their C-termini. This post-translational C-terminal processing is essential for Ras to become functional, but it remains unknown whether and how Ras C-terminal processing is regulated. Here we show that the C-terminal processing and subsequent plasma membrane localization of H-Ras as well as the activation of the downstream signaling pathways by H-Ras are prevented by JNK inhibition. Conversely, JNK activation by ultraviolet irradiation resulted in promotion of C-terminal processing of H-Ras. Furthermore, increased cell density promoted C-terminal processing of H-Ras most likely through an autocrine/paracrine mechanism, which was also blocked undermore » JNK-inhibited condition. Ras C-terminal processing was sensitive to JNK inhibition in the case of H- and N-Ras but not K-Ras, and in a variety of cell types. Thus, our results suggest for the first time that Ras C-terminal processing is a regulated mechanism in which JNK is involved.« less

Evidence of the direct involvement of the substrate TCP radical in functional switching from oxyferrous O2 carrier to ferric peroxidase in the dual-function hemoglobin/dehaloperoxidase from Amphitrite ornata.

PubMed

Sun, Shengfang; Sono, Masanori; Du, Jing; Dawson, John H

2014-08-05

The coelomic O2-binding hemoglobin dehaloperoxidase (DHP) from the sea worm Amphitrite ornata is a dual-function heme protein that also possesses a peroxidase activity. Two different starting oxidation states are required for reversible O2 binding (ferrous) and peroxidase (ferric) activity, bringing into question how DHP manages the two functions. In our previous study, the copresence of substrate 2,4,6-trichlorophenol (TCP) and H2O2 was found to be essential for the conversion of oxy-DHP to enzymatically active ferric DHP. On the basis of that study, a functional switching mechanism involving substrate radicals (TCP(•)) was proposed. To further support this mechanism, herein we report details of our investigations into the H2O2-mediated conversion of oxy-DHP to the ferric or ferryl ([TCP] < [H2O2]) state triggered by both biologically relevant [TCP and 4-bromophenol (4-BP)] and nonrelevant (ferrocyanide) compounds. At <50 μM H2O2, all of these conversion reactions are completely inhibited by ferric heme ligands (KCN and imidazole), indicating the involvement of ferric DHP. Furthermore, the spin-trapping reagent 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) effectively inhibits the TCP/4-BP (but not ferrocyanide)-triggered conversion of oxy-DHP to ferric DHP. These results and O2 concentration-dependent conversion rates observed in this study demonstrate that substrate TCP triggers the conversion of oxy-DHP to a peroxidase by TCP(•) oxidation of the deoxyferrous state. TCP(•) is progressively generated, by increasingly produced amounts of ferric DHP, upon H2O2 oxidation of TCP catalyzed initially by trace amounts of ferric enzyme present in the oxy-DHP sample. The data presented herein further address the mechanism of how the halophenolic substrate triggers the conversion of hemoglobin DHP into a peroxidase.

Home equity conversion plans as a source of retirement income.

PubMed

Springer, P B

1985-09-01

This article describes in detail a variety of home equity conversion plans and discusses their relevance for social security beneficiaries, as well as for the aged in general. Under these plans, a dormant asset--accumulated home equity--is converted into current retirement income. The plans vary: Some are debt instruments; others involve the sale and leaseback of the residence. Some provide income for a fixed term; others offer a lifetime annuity. Some include a public subsidy; others are free of governmental involvement. The advantages and disadvantages of these plans, as well as examples of how they operate and their respective income potential, are discussed in this article. The relevance of home equity conversion plans for social security beneficiaries is illustrated by means of data from the Retirement History Study. These data allow comparison of various demographic groups in terms of their dependence on social security benefits. Each group is examined in terms of available home equity and home equity potential under several conversion plans.

Automatic conversational scene analysis in children with Asperger syndrome/high-functioning autism and typically developing peers.

PubMed

Tavano, Alessandro; Pesarin, Anna; Murino, Vittorio; Cristani, Marco

2014-01-01

Individuals with Asperger syndrome/High Functioning Autism fail to spontaneously attribute mental states to the self and others, a life-long phenotypic characteristic known as mindblindness. We hypothesized that mindblindness would affect the dynamics of conversational interaction. Using generative models, in particular Gaussian mixture models and observed influence models, conversations were coded as interacting Markov processes, operating on novel speech/silence patterns, termed Steady Conversational Periods (SCPs). SCPs assume that whenever an agent's process changes state (e.g., from silence to speech), it causes a general transition of the entire conversational process, forcing inter-actant synchronization. SCPs fed into observed influence models, which captured the conversational dynamics of children and adolescents with Asperger syndrome/High Functioning Autism, and age-matched typically developing participants. Analyzing the parameters of the models by means of discriminative classifiers, the dialogs of patients were successfully distinguished from those of control participants. We conclude that meaning-free speech/silence sequences, reflecting inter-actant synchronization, at least partially encode typical and atypical conversational dynamics. This suggests a direct influence of theory of mind abilities onto basic speech initiative behavior.

Membranes for Food and Bioproduct Processing

NASA Astrophysics Data System (ADS)

Avram, Alexandru M.

Modified membranes for process intensification in biomass hydrolysis: Production of biofuels and chemicals from lignocellulosic biomass is one of the leading candidates for replacement of petroleum based fuels and chemicals. However, conversion of lignocellulosic biomass into fuels and chemicals is not cost effective compared to the production of fuels and chemicals from crude oil reserves. Some novel and economically feasible approaches involve the use of ionic liquids as solvents or co-solvents, since these show improved solvation capability of cellulose over simple aqueous systems. Membranes offer unique opportunities for process intensification which involves fractionation of the resulting biomass hydrolysate leading to a more efficient and cheaper operation. This research attempts to develop membranes that would usher the economics of the biochemical conversion of lignocellulosic biomass into fuels and chemicals by recycling the expensive ionic liquid. The overall aim of this work is the development of novel membranes with unique surface properties that enable the selective separation of non-reacted cellulose and hydrolysis sugars from ionic liquids. Nanofiltration separation for application in food product engineering: With the advent of the modern, well-informed consumer who has high expectations from the nutritional value of consumed food products, novel approaches are being developed to produce nutrient-enhanced foods and drinks. As a response to the consumer needs, different techniques to recover, concentrate and retain as much as possible of bioactive compounds are being investigated. Membrane technology has the advantage of selective fractionation of food products (e.g. salt removal, removal of bitter-tasting compounds or removal of sugar for sweet taste adjustment), volume reduction, and product recovery at mild conditions. In this work, we use nanofiltration in dead-end and crossflow mode to concentrate polyphenols from blueberry pomace. Blueberry pomace is an overlooked waste product form the juice pressing of blueberries that contains high amounts of health-beneficial antioxidants. We aim at developing a simple, yet efficient membrane process that reduces the amount of water and thus concentrates the amount of polyphenols in the retentate.

Unaddressed participants’ gaze in multi-person interaction: optimizing recipiency

PubMed Central

Holler, Judith; Kendrick, Kobin H.

2015-01-01

One of the most intriguing aspects of human communication is its turn-taking system. It requires the ability to process on-going turns at talk while planning the next, and to launch this next turn without considerable overlap or delay. Recent research has investigated the eye movements of observers of dialogs to gain insight into how we process turns at talk. More specifically, this research has focused on the extent to which we are able to anticipate the end of current and the beginning of next turns. At the same time, there has been a call for shifting experimental paradigms exploring social-cognitive processes away from passive observation toward on-line processing. Here, we present research that responds to this call by situating state-of-the-art technology for tracking interlocutors’ eye movements within spontaneous, face-to-face conversation. Each conversation involved three native speakers of English. The analysis focused on question–response sequences involving just two of those participants, thus rendering the third momentarily unaddressed. Temporal analyses of the unaddressed participants’ gaze shifts from current to next speaker revealed that unaddressed participants are able to anticipate next turns, and moreover, that they often shift their gaze toward the next speaker before the current turn ends. However, an analysis of the complex structure of turns at talk revealed that the planning of these gaze shifts virtually coincides with the points at which the turns first become recognizable as possibly complete. We argue that the timing of these eye movements is governed by an organizational principle whereby unaddressed participants shift their gaze at a point that appears interactionally most optimal: It provides unaddressed participants with access to much of the visual, bodily behavior that accompanies both the current speaker’s and the next speaker’s turn, and it allows them to display recipiency with regard to both speakers’ turns. PMID:25709592

On bipolar ejection. [of matter in astronomical systems

NASA Technical Reports Server (NTRS)

Cameron, A. G. W.

1985-01-01

Observations of bipolar outflows, including jets often with clumpy concentrations of matter, have been made for a wide variety of astronomical systems. In most but not all of the systems, an accretion disk is present. It is proposed that the general process responsible for bipolar ejection involves the conversion of rotational energy into magnetic energy, usually in the form of a polar magnetic torus, deep in the interiors of the systems involved. If the buoyancy of the torus resullts in draining the field lines of most of the matter which they thread, then the acceleration of the remaining matter in the toroidal bubble may produce velocities in excess of the escape velocity from the surface of the system. It is contemplated that this process will be repeated many times in most systems. A discussion is given of the application of these ideas to protostars, to stars evolved beyond the main sequence, to neutron stars, and to black holes on both stellar and galactic scales.

Ligand-Mediated Ring → Cube Transformation in a Catalytic Subnanocluster: Co4O4(MeCN)n with n = 1-6.

PubMed

Luo, Sijie; Dibble, Collin J; Duncan, Michael A; Truhlar, Donald G

2014-08-07

We studied the Co4O4 subnanocluster and its MeCN-coated species using density functional theory, and we found that the Co4O4 core presents distinctive structures in bare and ligand-coated species. We propose a possible ligand-mediated ring → cube transformation mechanism during the ligand-coating process of the Co4O4 core due to the stronger binding energies of the MeCN ligands to the 3D distorted cube structure than to the 2D ring and ladder structures; theory indicates that three ligands are sufficient to stabilize the cube structure. Both ring and cube structures are ferromagnetic. Our finding is potentially useful for understanding the catalysis mechanism of Co4O4 species, which have important applications in solar energy conversion and water splitting; these catalysis reactions usually involve frequent addition and subtraction of various ligands and thus possibly involve core rearrangement processes similar to our findings.

Significance of solvated electrons (e(aq)-) as promoters of life on earth.

PubMed

Getoff, Nikola

2014-01-01

Based on the present state of knowledge a new hypothesis concerning the origin of life on Earth is presented, and emphasizes the particular significance of solvated electrons (e(aq)(-)). Solvated electrons are produced in seawater, mainly by (40)K radiation and in atmospheric moisture by VUV light, electrical discharges and cosmic ray. Solvated electrons are involved in primary chemical processes and in biological processes. The conversion of aqueous CO2 and CO into simple organic substances, the generation of ammonia from N2 and water, the formation of amines, amino acids and simple proteins under the action of e(aq)(-) has been experimentally proven. Furthermore, it is supposed that the generation of the primitive cell and equilibria of primitive enzymes are also realized due to the strong reducing property of e(aq)(-). The presented hypothesis is mainly founded on recently obtained experimental results. The involvement of e(aq)(-) in such mechanisms, as well as their action as an initiator of life is also briefly discussed.

Empowerment model of biomass in west java

NASA Astrophysics Data System (ADS)

Mulyana, C.; Fitriani, N. I.; Saad, A.; Yuliah, Y.

2017-06-01

Scarcity of fossil energy accelerates the search of renewable energy sources as the substitution. In West Java, biomass has potential to be developed into bio-briquette because the resources are abundant. The objectives of this research are mapping the potency of biomass as bio-briquette in West Java, and making the model of the empowerment biomass potential involving five fundamental step which are raw material, pre-processing process, conversion mechanism, products, and end user. The main object of this model focused on 3 forms which are solid, liquid, and gas which was made by involving the community component as the owner biomass, district government, academics and researcher communities, related industries as users of biomass, and the central government as the policy holders and investors as a funder. In the model was described their respective roles and mutual relationship one with another so that the bio-briquette as a substitute of fossil fuels can be realized. Application of this model will provide the benefits in renewability energy sources, environmental, socio economical and energy security.

Leishmania mexicana differentiation involves a selective plasma membrane autophagic-like process.

PubMed

Dagger, Francehuli; Bengio, Camila; Martinez, Angel; Ayesta, Carlos

2017-11-23

Parasites of the Leishmania genus, which are the causative agents of leishmaniasis, display a complex life cycle, from a flagellated form (promastigotes) residing in the midgut of the phlebotomine vector to a non-flagellated form (amastigote) invading the mammalian host. The cellular process for the conversion between these forms is an interesting biological phenomenon involving modulation of the plasma membrane. In this study, we describe a selective autophagic-like process during the in vitro differentiation of Leishmania mexicana promastigote to amastigote-like cells. This process is responsible for size reduction and shape change of the promastigote (15-20 μm long) to the rounded amastigote-like form (4-5 μm long), identical to the one that infects host macrophages. This autophagic-like process is characterized by a profound folding of the plasma membrane and the presence of abundant cytoplasmic lipid droplets that may be the product of changes in the lipid metabolism. The key feature for the differentiation process at either pH 7.0 or pH 5.5 is the shift in temperature from 25 to 35 °C. Flagella shortening during the differentiation process appears as the product of continuous flagellar microtubular disassembly that is also accompanied by changes in mitochondrion localization. Drugs directed at blocking the parasite autophagic-like process could be important as new strategies to fight the disease.

Symptom-specific amygdala hyperactivity modulates motor control network in conversion disorder.

PubMed

Hassa, Thomas; Sebastian, Alexandra; Liepert, Joachim; Weiller, Cornelius; Schmidt, Roger; Tüscher, Oliver

2017-01-01

Initial historical accounts as well as recent data suggest that emotion processing is dysfunctional in conversion disorder patients and that this alteration may be the pathomechanistic neurocognitive basis for symptoms in conversion disorder. However, to date evidence of direct interaction of altered negative emotion processing with motor control networks in conversion disorder is still lacking. To specifically study the neural correlates of emotion processing interacting with motor networks we used a task combining emotional and sensorimotor stimuli both separately as well as simultaneously during functional magnetic resonance imaging in a well characterized group of 13 conversion disorder patients with functional hemiparesis and 19 demographically matched healthy controls. We performed voxelwise statistical parametrical mapping for a priori regions of interest within emotion processing and motor control networks. Psychophysiological interaction (PPI) was used to test altered functional connectivity of emotion and motor control networks. Only during simultaneous emotional stimulation and passive movement of the affected hand patients displayed left amygdala hyperactivity. PPI revealed increased functional connectivity in patients between the left amygdala and the (pre-)supplemental motor area and the subthalamic nucleus, key regions within the motor control network. These findings suggest a novel mechanistic direct link between dysregulated emotion processing and motor control circuitry in conversion disorder.

Planetary image conversion task

NASA Technical Reports Server (NTRS)

Martin, M. D.; Stanley, C. L.; Laughlin, G.

1985-01-01

The Planetary Image Conversion Task group processed 12,500 magnetic tapes containing raw imaging data from JPL planetary missions and produced an image data base in consistent format on 1200 fully packed 6250-bpi tapes. The output tapes will remain at JPL. A copy of the entire tape set was delivered to US Geological Survey, Flagstaff, Ariz. A secondary task converted computer datalogs, which had been stored in project specific MARK IV File Management System data types and structures, to flat-file, text format that is processable on any modern computer system. The conversion processing took place at JPL's Image Processing Laboratory on an IBM 370-158 with existing software modified slightly to meet the needs of the conversion task. More than 99% of the original digital image data was successfully recovered by the conversion task. However, processing data tapes recorded before 1975 was destructive. This discovery is of critical importance to facilities responsible for maintaining digital archives since normal periodic random sampling techniques would be unlikely to detect this phenomenon, and entire data sets could be wiped out in the act of generating seemingly positive sampling results. Reccomended follow-on activities are also included.

Evaluation of the mathematical and economic basis for conversion processes in the LEAP energy-economy model

NASA Astrophysics Data System (ADS)

Oblow, E. M.

1982-10-01

An evaluation was made of the mathematical and economic basis for conversion processes in the Long-term Energy Analysis Program (LEAP) energy economy model. Conversion processes are the main modeling subunit in LEAP used to represent energy conversion industries and are supposedly based on the classical economic theory of the firm. Questions about uniqueness and existence of LEAP solutions and their relation to classical equilibrium economic theory prompted the study. An analysis of classical theory and LEAP model equations was made to determine their exact relationship. The conclusions drawn from this analysis were that LEAP theory is not consistent with the classical theory of the firm. Specifically, the capacity factor formalism used by LEAP does not support a classical interpretation in terms of a technological production function for energy conversion processes. The economic implications of this inconsistency are suboptimal process operation and short term negative profits in years where plant operation should be terminated. A new capacity factor formalism, which retains the behavioral features of the original model, is proposed to resolve these discrepancies.

ALD5, PAD1, ATF1 and ATF2 facilitate the catabolism of coniferyl aldehyde, ferulic acid and p-coumaric acid in Saccharomyces cerevisiae

PubMed Central

Adeboye, Peter Temitope; Bettiga, Maurizio; Olsson, Lisbeth

2017-01-01

The ability of Saccharomyces cerevisiae to catabolize phenolic compounds remains to be fully elucidated. Conversion of coniferyl aldehyde, ferulic acid and p-coumaric acid by S. cerevisiae under aerobic conditions was previously reported. A conversion pathway was also proposed. In the present study, possible enzymes involved in the reported conversion were investigated. Aldehyde dehydrogenase Ald5, phenylacrylic acid decarboxylase Pad1, and alcohol acetyltransferases Atf1 and Atf2, were hypothesised to be involved. Corresponding genes for the four enzymes were overexpressed in a S. cerevisiae strain named APT_1. The ability of APT_1 to tolerate and convert the three phenolic compounds was tested. APT_1 was also compared to strains B_CALD heterologously expressing coniferyl aldehyde dehydrogenase from Pseudomonas, and an ald5Δ strain, all previously reported. APT_1 exhibited the fastest conversion of coniferyl aldehyde, ferulic acid and p-coumaric acid. Using the intermediates and conversion products of each compound, the catabolic route of coniferyl aldehyde, ferulic acid and p-coumaric acid in S. cerevisiae was studied in greater detail. PMID:28205618

Conversion of direct process high-boiling residue to monosilanes

DOEpatents

Brinson, Jonathan Ashley; Crum, Bruce Robert; Jarvis, Jr., Robert Frank

2000-01-01

A process for the production of monosilanes from the high-boiling residue resulting from the reaction of hydrogen chloride with silicon metalloid in a process typically referred to as the "direct process." The process comprises contacting a high-boiling residue resulting from the reaction of hydrogen chloride and silicon metalloid, with hydrogen gas in the presence of a catalytic amount of aluminum trichloride effective in promoting conversion of the high-boiling residue to monosilanes. The present process results in conversion of the high-boiling residue to monosilanes. At least a portion of the aluminum trichloride catalyst required for conduct of the process may be formed in situ during conduct of the direct process and isolation of the high-boiling residue.

Theoretical insights into multiscale electronic processes in organic photovoltaics

NASA Astrophysics Data System (ADS)

Tretiak, Sergei

Present day electronic devices are enabled by design and implementation of precise interfaces that control the flow of charge carriers. This requires robust and predictive multiscale approaches for theoretical description of underlining complex phenomena. Combined with thorough experimental studies such approaches provide a reliable estimate of physical properties of nanostructured materials and enable a rational design of devices. From this perspective I will discuss first principle modeling of small-molecule bulk-heterojunction organic solar cells and push-pull chromophores for tunable-color organic light emitters. The emphasis is on electronic processes involving intra- and intermolecular energy or charge transfer driven by strong electron-phonon coupling inherent to pi-conjugated systems. Finally I will describe how precise manipulation and control of organic-organic interfaces in a photovoltaic device can increase its power conversion efficiency by 2-5 times in a model bilayer system. Applications of these design principles to practical architectures like bulk heterojunction devices lead to an enhancement in power conversion efficiency from 4.0% to 7.0%. These interface manipulation strategies are universally applicable to any donor-acceptor interface, making them both fundamentally interesting and technologically important for achieving high efficiency organic electronic devices.

Kinetic conversion of CO to CH4 in the Solar System

NASA Technical Reports Server (NTRS)

Yung, Y. L.; Allen, M.; Pinto, J. P.

1991-01-01

Some of the most interesting chemistry in the Solar System involves changes in the oxidation state of the simple carbon species. The chemical pathways for the conversion of CH4 to CO and CO2 are for the most part known. The reverse process, the reduction of CO to CH4, is, however, poorly understood. This is surprising in view of the importance of the reduction process in the chemistry of the Solar System. Recently we investigated the chemical kinetics of a hitherto unsuspected reaction. It is argued that the formation of the methoxy radical (CH3O) from H+H2CO may play an essential role in the reduction of CO to CH4. The rate coefficient for this reaction has been estimated using the approximate theory of J. Troe and transition state theory. We will discuss the implications of this reaction for the chemistry of CO on Jupiter, in the solar nebula, for interpreting the laboratory experiments of A. Bar-Nun and A. Shaviv and A. Bar-Nun and S. Chang, and for organic synthesis in the prebiotic terrestrial atmosphere. The possible relation of CO reduction in the solar nebula and polyoxymethylene observed in comet Halley will be discussed.

In Conversation: Transforming Experience Into Learning.

ERIC Educational Resources Information Center

Baker, Ann C.; And Others

1997-01-01

Simulations and games are designed to provide participants with an experiential context for reflection and learning in classrooms, corporate training centers, and community-based organizations. A conversational approach to debriefing sessions is one way to more deeply involve participants in exploring the meaning of their experience from multiple…

Prospects for Irradiation in Cellulosic Ethanol Production

PubMed Central

Saini, Anita; Aggarwal, Neeraj K.; Sharma, Anuja; Yadav, Anita

2015-01-01

Second generation bioethanol production technology relies on lignocellulosic biomass composed of hemicelluloses, celluloses, and lignin components. Cellulose and hemicellulose are sources of fermentable sugars. But the structural characteristics of lignocelluloses pose hindrance to the conversion of these sugar polysaccharides into ethanol. The process of ethanol production, therefore, involves an expensive and energy intensive step of pretreatment, which reduces the recalcitrance of lignocellulose and makes feedstock more susceptible to saccharification. Various physical, chemical, biological, or combined methods are employed to pretreat lignocelluloses. Irradiation is one of the common and promising physical methods of pretreatment, which involves ultrasonic waves, microwaves, γ-rays, and electron beam. Irradiation is also known to enhance the effect of saccharification. This review explains the role of different radiations in the production of cellulosic ethanol. PMID:26839707

Transepithelial transport of alpha-lipoic acid across human intestinal Caco-2 cell monolayers.

PubMed

Takaishi, Naoki; Yoshida, Kazutaka; Satsu, Hideo; Shimizu, Makoto

2007-06-27

Alpha-lipoic acid (LA) is used in dietary supplements or food with antioxidative functions. The mechanism for the intestinal absorption of alpha-lipoic acid was investigated in this study by using human intestinal Caco-2 cell monolayers. LA was rapidly transported across the Caco-2 cell monolayers, this transport being energy-dependent, suggesting transporter-mediated transport to be the mechanism involved. The LA transport was strongly dependent on the pH value, being accelerated in the acidic pH range. Furthermore, such monocarboxylic acids as benzoic acid and medium-chain fatty acids significantly inhibited LA transport, suggesting that a proton-linked monocarboxylic acid transporter (MCT) was involved in the intestinal transport of LA. The conversion of LA to the more antioxidative dihydrolipoic acid was also apparent during the transport process.

Conversion of Indigenous Agricultural Waste Feedstocks to Fuel Ethanol. Cooperative Research and Development Final Report, CRADA Number CRD-13-504

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

Elander, Richard

This Cooperative Research and Development Agreement (CRADA) is between the National Renewable Energy Laboratory (NREL), a world leader in biomass conversion research and Ecopetrol American Inc., Ecopetrol S.A.'s U.S. subsidiary. The research and development efforts described in the Joint Work Statement (JWS) will take advantage of the strengths of both parties. NREL will use its Integrated Biorefinery Facility and vast experience in the conversion of lignocellulosic feedstocks to fuel ethanol to develop processes for the conversion of Ecopetrol's feedstocks. Ecopetrol will establish the infrastructure in Columbia to commercialize the conversion process.

3D Maps from Multiple MRI Illustrate Changing Atrophy Patterns as Subjects Progress from MCI to AD

PubMed Central

Whitwell, Jennifer L; Przybelski, Scott; Weigand, Stephen D; Knopman, David S; Boeve, Bradley F; Petersen, Ronald C; Jack, Clifford R

2009-01-01

Summary Mild cognitive impairment (MCI), particularly the amnestic subtype (aMCI), is considered as a transitional stage between normal aging and a diagnosis of clinically probable Alzheimer's disease (AD). The aMCI construct is particularly useful as it provides an opportunity to assess a clinical stage which in most subjects represents prodromal AD. The aim of this study was to assess the progression of cerebral atrophy over multiple serial MRI during the period from aMCI to conversion to AD. Thirty-three subjects were selected that fulfilled clinical criteria for aMCI and had three serial MRI scans: the first scan approximately three years before conversion to AD, the second scan approximately one year before conversion, and the third scan at the time of conversion from aMCI to AD. A group of 33 healthy controls were age and gender-matched to the study cohort. Voxel-based morphometry (VBM) was used to assess patterns of grey matter atrophy in the aMCI subjects at each time-point compared to the control group. Customized templates and prior probability maps were used to avoid normalization and segmentation bias. The pattern of grey matter loss in the aMCI subject scans that were three years before conversion was focused primarily on the medial temporal lobes, including the amygdala, anterior hippocampus and entorhinal cortex, with some additional involvement of the fusiform gyrus, compared to controls. The extent and magnitude of the cerebral atrophy further progressed by the time the subjects were one year before conversion. At this point atrophy in the temporal lobes spread to include the middle temporal gyrus, and extended into more posterior regions of the temporal lobe to include the entire extent of the hippocampus. The parietal lobe also started to become involved. By the time the subjects had converted to a clinical diagnosis of AD the pattern of grey matter atrophy had become still more widespread with more severe involvement of the medial temporal lobes and the temporoparietal association cortices and, for the first time, substantial involvement of the frontal lobes. This pattern of progression fits well with the Braak and Braak neurofibrillary pathological staging scheme in AD. It suggests that the earliest changes occur in the anterior medial temporal lobe and fusiform gyrus, and that these changes occur at least three years before conversion to AD. These results also suggest that 3-dimensional patterns of grey matter atrophy may help to predict the time to conversion in subjects with aMCI. PMID:17533169

Glimpses into the blind spot: Social interaction and autism.

PubMed

Bottema-Beutel, Kristen

2017-07-01

A primary feature of autism spectrum disorder (ASD) is marked difficulty in social interactions. Despite the centrality of social interaction differences to the clinical presentation of ASD, only a small portion of research in this field characterizes interaction in everyday social contexts. This theoretical paper reviews the growing corpus of interactional research on ASD, including discourse analysis (DA) and conversation analysis (CA) approaches. DA and CA are micro-analytic methods aimed at understanding the organizational structure of, and actions pursued within, social encounters. These methods are aligned with enactive theories of social interaction. The bulk of current ASD research construes social interaction as involving isolated individuals who represent and/or theorize about the minds of an interlocutor. Enactive approaches posit that achieving intersubjectivity does not require theories of other minds, but instead a propensity for coordinating social actions with others. Through the complementary lenses of enactivism and interactional research, I offer an account of autistic social interaction as involving differences in interactional coordination, interactional priorities, and the enactment of meaning across conversational turns. This characterization challenges the explanatory role of cognitive processes such as Theory of Mind, and points to new avenues for conceptualizing, measuring, and supporting social interaction. Copyright © 2017 Elsevier Inc. All rights reserved.

"Spin-dependent" \\varvec{μ → e} conversion on light nuclei

NASA Astrophysics Data System (ADS)

Davidson, Sacha; Kuno, Yoshitaka; Saporta, Albert

2018-02-01

The experimental sensitivity to μ → e conversion will improve by four or more orders of magnitude in coming years, making it interesting to consider the "spin-dependent" (SD) contribution to the rate. This process does not benefit from the atomic-number-squared enhancement of the spin-independent (SI) contribution, but probes different operators. We give details of our recent estimate of the spin-dependent rate, expressed as a function of operator coefficients at the experimental scale. Then we explore the prospects for distinguishing coefficients or models by using different targets, both in an EFT perspective, where a geometric representation of different targets as vectors in coefficient space is introduced, and also in three leptoquark models. It is found that comparing the rate on isotopes with and without spin could allow one to detect spin-dependent coefficients that are at least a factor of few larger than the spin-independent ones. Distinguishing among the axial, tensor and pseudoscalar operators that induce the SD rate would require calculating the nuclear matrix elements for the second two. Comparing the SD rate on nuclei with an odd proton vs. odd neutron could allow one to distinguish operators involving u quarks from those involving d quarks; this is interesting because the distinction is difficult to make for SI operators.

Amylolytic bacterial lactic acid fermentation - a review.

PubMed

Reddy, Gopal; Altaf, Md; Naveena, B J; Venkateshwar, M; Kumar, E Vijay

2008-01-01

Lactic acid, an enigmatic chemical has wide applications in food, pharmaceutical, leather, textile industries and as chemical feed stock. Novel applications in synthesis of biodegradable plastics have increased the demand for lactic acid. Microbial fermentations are preferred over chemical synthesis of lactic acid due to various factors. Refined sugars, though costly, are the choice substrates for lactic acid production using Lactobacillus sps. Complex natural starchy raw materials used for production of lactic acid involve pretreatment by gelatinization and liquefaction followed by enzymatic saccharification to glucose and subsequent conversion of glucose to lactic acid by Lactobacillus fermentation. Direct conversion of starchy biomass to lactic acid by bacteria possessing both amylolytic and lactic acid producing character will eliminate the two step process to make it economical. Very few amylolytic lactic acid bacteria with high potential to produce lactic acid at high substrate concentrations are reported till date. In this view, a search has been made for various amylolytic LAB involved in production of lactic acid and utilization of cheaply available renewable agricultural starchy biomass. Lactobacillus amylophilus GV6 is an efficient and widely studied amylolytic lactic acid producing bacteria capable of utilizing inexpensive carbon and nitrogen substrates with high lactic acid production efficiency. This is the first review on amylolytic bacterial lactic acid fermentations till date.

Quantum state conversion in opto-electro-mechanical systems via shortcut to adiabaticity

NASA Astrophysics Data System (ADS)

Zhou, Xiao; Liu, Bao-Jie; Shao, L.-B.; Zhang, Xin-Ding; Xue, Zheng-Yuan

2017-09-01

Adiabatic processes have found many important applications in modern physics, the distinct merit of which is that accurate control over process timing is not required. However, such processes are slow, which limits their application in quantum computation, due to the limited coherent times of typical quantum systems. Here, we propose a scheme to implement quantum state conversion in opto-electro-mechanical systems via a shortcut to adiabaticity, where the process can be greatly speeded up while precise timing control is still not necessary. In our scheme, by modifying only the coupling strength, we can achieve fast quantum state conversion with high fidelity, where the adiabatic condition does not need to be met. In addition, the population of the unwanted intermediate state can be further suppressed. Therefore, our protocol presents an important step towards practical state conversion between optical and microwave photons, and thus may find many important applications in hybrid quantum information processing.

Learning through Conversation.

ERIC Educational Resources Information Center

Kelly, Patricia R.; Klein, Adria F.; Pinnell, Gay Su

1996-01-01

Through teacher-child conversation, experts use oral language to help novices take on more complex tasks; and Reading Recovery children, who are obviously having difficulty with school-based learning, are especially in need of significant conversations with adults. Reading and writing processes are supported through conversation with Reading…

Microemulsion impregnated catalyst composite and use thereof in a synthesis gas conversion process

DOEpatents

Abrevaya, Hayim; Targos, William M.

1987-01-01

A catalyst composition for synthesis gas conversion comprising a ruthenium metal component deposited on a support carrier wherein the average metal particle size is less than about 100 A. The method of manufacture of the composition via a reverse micelle impregnation technique and the use of the composition in a Fischer-Tropsch conversion process is also disclosed.

Process for preparing a chemical compound enriched in isotope content. [nitrogen 15-enriched nitric acid

DOEpatents

Michaels, E.D.

1981-02-25

A process to prepare a chemical enriched in isotope content includes: a chemical exchange reaction between a first and second compound which yields an isotopically enriched first compound and an isotopically depleted second compound; the removal of a portion of the first compound as product and the removal of a portion of the second compound as spent material; the conversion of the remainder of the first compound to the second compound for reflux at the product end of the chemical exchange reaction region; the conversion of the remainder of the second compound to the first compound for reflux at the spent material end of the chemical exchange region; and the cycling of the additional chemicals produced by one conversion reaction to the other conversion reaction, for consumption therein. One of the conversion reactions is an oxidation reaction, and the energy that it yields is used to drive the other conversion reaction, a reduction. The reduction reaction is carried out in a solid polymer electrolyte electrolytic reactor. The overall process is energy efficient and yields no waste by-products. A particular embodiment of the process in the production of nitrogen-15-enriched nitric acid.

The rate of meiotic gene conversion varies by sex and age

PubMed Central

Halldorsson, Bjarni V.; Hardarson, Marteinn T.; Kehr, Birte; Styrkarsdottir, Unnur; Gylfason, Arnaldur; Thorleifsson, Gudmar; Zink, Florian; Jonasdottir, Adalbjorg; Jonasdottir, Aslaug; Sulem, Patrick; Masson, Gisli; Thorsteinsdottir, Unnur; Helgason, Agnar; Kong, Augustine; Gudbjartsson, Daniel F.; Stefansson, Kari

2016-01-01

Meiotic recombination involves a combination of gene conversion and crossover events that along with mutations produce germline genetic diversity. Here, we report the discovery of 3,176 SNP and 61 indel gene conversions. Our estimate of the non-crossover (NCO) gene conversion rate (G) is 7.0 for SNPs and 5.8 for indels per Mb per generation, and the GC bias is 67.6%. For indels we demonstrate a 65.6% preference for the shorter allele. NCO gene conversions from mothers are longer than those from fathers and G is 2.17 times greater in mothers. Notably, G increases with the age of mothers, but not fathers. A disproportionate number of NCO gene conversions in older mothers occur outside double strand break (DSB) regions and in regions with relatively low GC content. This points to age-related changes in the mechanisms of meiotic gene conversions in oocytes. PMID:27643539

Hydrogen-atom tunneling through a very high barrier; spontaneous thiol → thione conversion in thiourea isolated in low-temperature Ar, Ne, H2 and D2 matrices.

PubMed

Rostkowska, Hanna; Lapinski, Leszek; Nowak, Maciej J

2018-05-23

Spontaneous thiol → thione hydrogen-atom transfer has been investigated for molecules of thiourea trapped in Ar, Ne, normal-H2 (n-H2) and normal-D2 (n-D2) low-temperature matrices. The most stable thione isomer was the only form of the compound present in the matrices after their deposition. According to MP2/6-311++G(2d,p) calculations, the thiol tautomer should be higher in energy by 62.5 kJ mol-1. This less stable thiol form of the compound was photochemically generated in a thione → thiol process, occurring upon UV irradiation of the matrix. Subsequently, a very slow spontaneous conversion of the thiol tautomer into the thione form was observed for the molecules isolated in Ar, Ne, n-H2 and n-D2 matrices kept at 3.5 K and in the dark. Since the thiol → thione transformation in thiourea is a process involving the dissociation of a chemical bond, the barrier for this hydrogen-atom transfer is very high (104-181 kJ mol-1). Crossing such a high potential-energy barrier at a temperature as low as 3.5 K, is possible only by hydrogen-atom tunneling. The experimentally measured time constants of this tunneling process: 52 h (Ar), 76 h (Ne), 94 h (n-H2) and 94 h (n-D2), do not differ much from one another. Hence, the dependence of the tunneling rate on the matrix environment is not drastic. The progress of the thiol → thione conversion was also monitored for Ar matrices at different temperature: 3.5 K, 9 K and 15 K. For this temperature range, the experiments revealed no detectable temperature dependence of the rate of the tunneling process.

Measure for Measure: Using Portfolios in K-8 Mathematics.

ERIC Educational Resources Information Center

Kuhs, Therese M.

This book attempts to portray the reality that teachers face when trying to use portfolios. It uses anecdotes and examples that help carry important messages about portfolio use and contains model conversations and interactions. The conversations between teachers and students demonstrate strategies for involving children in the assessment process…

Children with Autism Spectrum Disorder: Teaching Conversation Involving Feelings about Events

ERIC Educational Resources Information Center

Conallen, K.; Reed, P.

2017-01-01

Background: Two procedures were developed to teach individuals with Autism Spectrum Disorders labels (tacts) for various private events (emotions): Study 1 attempted to distinguish them from pure tacts and mands (requests); and Study 2 attempted to train initiating a conversation with grammatically correct subject-verb-comment construction.…

Architecture for Building Conversational Agents that Support Collaborative Learning

ERIC Educational Resources Information Center

Kumar, R.; Rose, C. P.

2011-01-01

Tutorial Dialog Systems that employ Conversational Agents (CAs) to deliver instructional content to learners in one-on-one tutoring settings have been shown to be effective in multiple learning domains by multiple research groups. Our work focuses on extending this successful learning technology to collaborative learning settings involving two or…

Enzymes and microorganisms in food industry waste processing and conversion to useful products: a review of the literature

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

Carroad, P.A.; Wilke, C.R.

1976-12-01

Bioconversion of food processing wastes is receiving increased attention with the realization that waste components represent an available and utilizable resource for conversion to useful products. Liquid wastes are characterized as dilute streams containing sugars, starches, proteins, and fats. Solid wastes are generally cellulosic, but may contain other biopolymers. The greatest potential for economic bioconversion is represented by processes to convert cellulose to glucose, glucose to alcohol and protein, starch to invert sugar, and dilute waste streams to methane by anaerobic digestion. Microbial or enzymatic processes to accomplish these conversions are described.

Active-sterile neutrino conversion: consequences for the r-process and supernova neutrino detection

NASA Astrophysics Data System (ADS)

Fetter, J.; McLaughlin, G. C.; Balantekin, A. B.; Fuller, G. M.

2003-02-01

We examine active-sterile neutrino conversion in the late time post-core-bounce supernova environment. By including the effect of feedback on the Mikheyev-Smirnov-Wolfenstein (MSW) conversion potential, we obtain a large range of neutrino mixing parameters which produce a favorable environment for the r-process. We look at the signature of this effect in the current generation of neutrino detectors now coming on line. We also investigate the impact of the neutrino-neutrino forward-scattering-induced potential on the MSW conversion.

Nonlocal thermodynamic equilibrium processes in ozone - Implications for the energy budget of the mesosphere and lower thermosphere

NASA Technical Reports Server (NTRS)

Milynczak, Martin G.

1991-01-01

The conversion of chemical potential energy and infrared radiative energy to kinetic energy by non-LTE processes involving ozone is a potentially significant source of heat in the terrestrial upper mesosphere and lower thermosphere. Heating rates are calculated and compared using two different statistical equilibrium models previously applied in the analysis of measurements of limb emission from ozone. The calculated heating depends strongly on the assumed distribution and relaxation of energy in the quasi-nascent ozone molecule. Finally, in the absence of a detailed data base of rate coefficients it may be possible to estimate the heating rate due to non-LTE processes in ozone from appropriate satellite measurements of the ozone concentration and of the infrared emission from ozone in the 9-12 micron spectral interval.

Flow-through biological conversion of lignocellulosic biomass

DOEpatents

Herring, Christopher D.; Liu, Chaogang; Bardsley, John

2014-07-01

The present invention is directed to a process for biologically converting carbohydrates from lignocellulosic biomass comprising the steps of: suspending lignocellulosic biomass in a flow-through reactor, passing a reaction solution into the reactor, wherein the solution is absorbed into the biomass substrate and at least a portion of the solution migrates through said biomass substrate to a liquid reservoir, recirculating the reaction solution in the liquid reservoir at least once to be absorbed into and migrate through the biomass substrate again. The biological converting of the may involve hydrolyzing cellulose, hemicellulose, or a combination thereof to form oligosaccharides, monomelic sugars, or a combination thereof; fermenting oligosaccharides, monomelic sugars, or a combination thereof to produce ethanol, or a combination thereof. The process can further comprise removing the reaction solution and processing the solution to separate the ethanol produced from non-fermented solids.

The Impact of Mutation and Gene Conversion on the Local Diversification of Antigen Genes in African Trypanosomes

PubMed Central

Gjini, Erida; Haydon, Daniel T.; Barry, J. David; Cobbold, Christina A.

2012-01-01

Patterns of genetic diversity in parasite antigen gene families hold important information about their potential to generate antigenic variation within and between hosts. The evolution of such gene families is typically driven by gene duplication, followed by point mutation and gene conversion. There is great interest in estimating the rates of these processes from molecular sequences for understanding the evolution of the pathogen and its significance for infection processes. In this study, a series of models are constructed to investigate hypotheses about the nucleotide diversity patterns between closely related gene sequences from the antigen gene archive of the African trypanosome, the protozoan parasite causative of human sleeping sickness in Equatorial Africa. We use a hidden Markov model approach to identify two scales of diversification: clustering of sequence mismatches, a putative indicator of gene conversion events with other lower-identity donor genes in the archive, and at a sparser scale, isolated mismatches, likely arising from independent point mutations. In addition to quantifying the respective probabilities of occurrence of these two processes, our approach yields estimates for the gene conversion tract length distribution and the average diversity contributed locally by conversion events. Model fitting is conducted using a Bayesian framework. We find that diversifying gene conversion events with lower-identity partners occur at least five times less frequently than point mutations on variant surface glycoprotein (VSG) pairs, and the average imported conversion tract is between 14 and 25 nucleotides long. However, because of the high diversity introduced by gene conversion, the two processes have almost equal impact on the per-nucleotide rate of sequence diversification between VSG subfamily members. We are able to disentangle the most likely locations of point mutations and conversions on each aligned gene pair. PMID:22735079

Automatic Conversational Scene Analysis in Children with Asperger Syndrome/High-Functioning Autism and Typically Developing Peers

PubMed Central

Tavano, Alessandro; Pesarin, Anna; Murino, Vittorio; Cristani, Marco

2014-01-01

Individuals with Asperger syndrome/High Functioning Autism fail to spontaneously attribute mental states to the self and others, a life-long phenotypic characteristic known as mindblindness. We hypothesized that mindblindness would affect the dynamics of conversational interaction. Using generative models, in particular Gaussian mixture models and observed influence models, conversations were coded as interacting Markov processes, operating on novel speech/silence patterns, termed Steady Conversational Periods (SCPs). SCPs assume that whenever an agent's process changes state (e.g., from silence to speech), it causes a general transition of the entire conversational process, forcing inter-actant synchronization. SCPs fed into observed influence models, which captured the conversational dynamics of children and adolescents with Asperger syndrome/High Functioning Autism, and age-matched typically developing participants. Analyzing the parameters of the models by means of discriminative classifiers, the dialogs of patients were successfully distinguished from those of control participants. We conclude that meaning-free speech/silence sequences, reflecting inter-actant synchronization, at least partially encode typical and atypical conversational dynamics. This suggests a direct influence of theory of mind abilities onto basic speech initiative behavior. PMID:24489674

Dielectric controlled excited state relaxation pathways of a representative push-pull stilbene: a mechanistic study using femtosecond fluorescence up-conversion technique.

PubMed

Rafiq, Shahnawaz; Sen, Pratik

2013-02-28

Femtosecond fluorescence up-conversion technique was employed to reinvestigate the intriguing dependence of fluorescence quantum yield of trans-4-dimethylamino-4(')-nitrostilbene (DNS) on dielectric properties of the media. In polar solvents, such as methanol and acetonitrile, the two time components of the fluorescence transients were assigned to intramolecular charge transfer (ICT) dynamics and to the depletion of the ICT state to the ground state via internal conversion along the torsional coordinate of nitro moiety. The viscosity independence of the first time component indicates the absence of any torsional coordinate in the charge transfer process. In slightly polar solvent (carbon tetrachloride) the fluorescence transients show a triple exponential behavior. The first time component was assigned to the formation of the ICT state on a 2 ps time scale. Second time component was assigned to the relaxation of the ICT state via two torsion controlled channels. First channel involves the torsional motion about the central double bond leading to the trans-cis isomerization via a conical intersection or avoided crossing. The other channel contributing to the depopulation of ICT state involves the torsional coordinates of dimethylanilino and∕or nitrophenyl moieties and leads to the formation of a conformationally relaxed state, which subsequently relaxes back to the ground state radiatively, and is responsible for the high fluorescence quantum yield of DNS in slightly polar solvents such as carbon tetrachloride, toluene, etc. The excited singlet state which is having a dominant π-π∗ character may also decay via intersystem crossing to the n-π∗ triplet manifold and thus accounts for the observed triplet yield of the molecule in slightly polar solvents.

Dielectric controlled excited state relaxation pathways of a representative push-pull stilbene: A mechanistic study using femtosecond fluorescence up-conversion technique

NASA Astrophysics Data System (ADS)

Rafiq, Shahnawaz; Sen, Pratik

2013-02-01

Femtosecond fluorescence up-conversion technique was employed to reinvestigate the intriguing dependence of fluorescence quantum yield of trans-4-dimethylamino-4'-nitrostilbene (DNS) on dielectric properties of the media. In polar solvents, such as methanol and acetonitrile, the two time components of the fluorescence transients were assigned to intramolecular charge transfer (ICT) dynamics and to the depletion of the ICT state to the ground state via internal conversion along the torsional coordinate of nitro moiety. The viscosity independence of the first time component indicates the absence of any torsional coordinate in the charge transfer process. In slightly polar solvent (carbon tetrachloride) the fluorescence transients show a triple exponential behavior. The first time component was assigned to the formation of the ICT state on a 2 ps time scale. Second time component was assigned to the relaxation of the ICT state via two torsion controlled channels. First channel involves the torsional motion about the central double bond leading to the trans-cis isomerization via a conical intersection or avoided crossing. The other channel contributing to the depopulation of ICT state involves the torsional coordinates of dimethylanilino and/or nitrophenyl moieties and leads to the formation of a conformationally relaxed state, which subsequently relaxes back to the ground state radiatively, and is responsible for the high fluorescence quantum yield of DNS in slightly polar solvents such as carbon tetrachloride, toluene, etc. The excited singlet state which is having a dominant π-π* character may also decay via intersystem crossing to the n-π* triplet manifold and thus accounts for the observed triplet yield of the molecule in slightly polar solvents.

Conversion of Stationary to Invasive Tumor Initiating Cells (TICs): Role of Hypoxia in Membrane Type 1-Matrix Metalloproteinase (MT1-MMP) Trafficking

PubMed Central

Li, Jian; Zucker, Stanley; Pulkoski-Gross, Ashleigh; Kuscu, Cem; Karaayvaz, Mihriban; Ju, Jingfang; Yao, Herui; Song, Erwei; Cao, Jian

2012-01-01

Emerging evidence has implicated the role of tumor initiating cells (TICs) in the process of cancer metastasis. The mechanism underlying the conversion of TICs from stationary to invasive remains to be characterized. In this report, we employed less invasive breast cancer TICs, SK-3rd, that displays CD44high/CD24low with high mammosphere-forming and tumorigenic capacities, to investigate the mechanism by which stationary TICs are converted to invasive TICs. Invasive ability of SK-3rd TICs was markedly enhanced when the cells were cultured under hypoxic conditions. Given the role of membrane type 1-matrix metalloproteinase (MT1-MMP) in cancer invasion/metastasis, we explored a possible involvement of MT1-MMP in hypoxia-induced TIC invasion. Silencing of MT1-MMP by a shRNA approach resulted in diminution of hypoxia-induced cell invasion in vitro and metastasis in vivo. Under hypoxic conditions, MT1-MMP redistributed from cytoplasmic storage pools to the cell surface of TICs, which coincides with the increased cell invasion. In addition, CD44, a cancer stem-like cell marker, inversely correlated with increased cell surface MT1-MMP. Interestingly, cell surface MT1-MMP gradually disappeared when the hypoxia-treated cells were switched to normoxia, suggesting the plasticity of TICs in response to oxygen content. Furthermore, we dissected the pathways leading to upregulated MT1-MMP in cytoplasmic storage pools under normoxic conditions, by demonstrating a cascade involving Twist1-miR10b-HoxD10 leading to enhanced MT1-MMP expression in SK-3rd TICs. These observations suggest that MT1-MMP is a key molecule capable of executing conversion of stationary TICs to invasive TICs under hypoxic conditions and thereby controlling metastasis. PMID:22679501

Recombination activity associated with thermal donor generation in monocrystalline silicon and effect on the conversion efficiency of heterojunction solar cells

NASA Astrophysics Data System (ADS)

Tomassini, M.; Veirman, J.; Varache, R.; Letty, E.; Dubois, S.; Hu, Y.; Nielsen, Ø.

2016-02-01

The recombination properties of the carrier lifetime-limiting center formed during the generation of oxygen-related thermal donors (so called "old" thermal donors) in n-type Czochralski silicon were determined over a wide range of thermal donors' concentrations. The procedure involved (1) determining the various energy levels associated with dopants with the help of temperature Hall effect measurements, (2) clarifying which energy level limits the carrier lifetime by temperature lifetime spectroscopy, and (3) determining the recombination parameters of the involved defect from room-temperature carrier lifetime curves. Our results support the fact that a deep energy level in the range of 0.2-0.3 eV below the conduction band limits the carrier lifetime. The second family of thermal donors, featuring bistable properties, was tentatively identified as the corresponding defect. From the obtained experimental data, the influence of the defect on the amorphous/crystalline silicon heterojunction solar cell conversion efficiency was simulated. It is observed that for extended donor generation, the carrier lifetime is reduced by orders-of-magnitude, leading to unacceptable losses in photovoltaic conversion efficiency. A key result is that even for samples with thermal donor concentrations of 1015 cm-3—often met in seed portions of commercial ingots—simulations reveal efficiency losses greater than 1% absolute for state-of-the-art cells, in agreement with recent experimental studies from our group. This result indicates to crystal growers the importance to mitigate the formation of thermal donors or to develop cost-effective processes to suppress them at the ingot/wafer scale. This is even more critical as ingot cool-down is likely to be slower for future larger ingots, thus promoting the formation of thermal donors.

Family Conferences in the Neonatal ICU: Observation of Communication Dynamics and Contributions.

PubMed

Boss, Renee D; Donohue, Pamela K; Larson, Susan M; Arnold, Robert M; Roter, Debra L

2016-03-01

Clinicians in the neonatal ICU must engage in clear and compassionate communication with families. Empirical, observational studies of neonatal ICU family conferences are needed to develop counseling best practices and to train clinicians in key communication skills. We devised a pilot study to record and analyze how interdisciplinary neonatal ICU clinicians and parents navigate difficult conversations during neonatal ICU family conferences. We prospectively identified and audiotaped a convenience sample of neonatal ICU family conferences about "difficult news." Conversations were analyzed using the Roter interaction analysis system, a quantitative tool for assessing content and quality of patient-provider communication. An urban academic children's medical center with a 45-bed level IV neonatal ICU. Neonatal ICU parents and clinicians. None. We analyzed 19 family conferences that included 31 family members and 23 clinicians. The child's mother was included in all conferences, and a second parent, usually the father, was present in 13 conferences. All but one conference included multiple medical team members. On average, physicians contributed 65% of all dialogue, regardless of who else was present. Over half (56%) of this dialogue involved giving medical information; under 5% of clinician dialogue involved asking questions of the family, and families rarely (5% of dialogue) asked questions. Conversations were longer with the presence of nonphysician clinicians, but this did not increase the amount of dialogue about psychosocial information or increase parent dialogue. We collected a novel repository of audio-recorded neonatal ICU family meetings that offers insights into discussion content and process. These meetings were heavily focused on biomedical information even when interdisciplinary clinicians were present. Clinicians always talked more than parents, and no one asked many questions. Maximizing the participation of interdisciplinary clinicians in neonatal ICU family meetings may require explicit strategies. Methods to increase family engagement should be targeted.

Comparative efficiency of technologies for conversion and transportation of energy resources of Russia's eastern regions to NEA countries

NASA Astrophysics Data System (ADS)

Kler, Aleksandr; Tyurina, Elina; Mednikov, Aleksandr

2018-01-01

The paper presents perspective technologies for combined conversion of fossil fuels into synthetic liquid fuels and electricity. The comparative efficiency of various process flows of conversion and transportation of energy resources of Russia's east that are aimed at supplying electricity to remote consumers is presented. These also include process flows based on production of synthetic liquid fuel.

Microemulsion impregnated catalyst composite and use thereof in a synthesis gas conversion process

DOEpatents

Abrevaya, H.; Targos, W.M.

1987-12-22

A catalyst composition is described for synthesis gas conversion comprising a ruthenium metal component deposited on a support carrier wherein the average metal particle size is less than about 100 A. The method of manufacture of the composition via a reverse micelle impregnation technique and the use of the composition in a Fischer-Tropsch conversion process is also disclosed.

Surface Temperature Dependence of Hydrogen Ortho-Para Conversion on Amorphous Solid Water.

PubMed

Ueta, Hirokazu; Watanabe, Naoki; Hama, Tetsuya; Kouchi, Akira

2016-06-24

The surface temperature dependence of the ortho-to-para conversion of H_{2} on amorphous solid water is first reported. A combination of photostimulated desorption and resonance-enhanced multiphoton ionization techniques allowed us to sensitively probe the conversion on the surface of amorphous solid water at temperatures of 9.2-16 K. Within a narrow temperature window of 8 K, the conversion time steeply varied from ∼4.1×10^{3} to ∼6.4×10^{2}  s. The observed temperature dependence is discussed in the context of previously suggested models and the energy dissipation process. The two-phonon process most likely dominates the conversion rate at low temperatures.

Optimizing Immobilized Enzyme Performance in Cell-Free Environments to Produce Liquid Fuels

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

Belfort, Georges; Grimaldi, Joseph J.

2015-01-27

Limitations on biofuel production using cell culture (Escherichia coli, Clostridium, Saccharomyces cerevisiae, brown microalgae, blue-green algae and others) include low product (alcohol) concentrations (≤0.2 vol%) due to feedback inhibition, instability of cells, and lack of economical product recovery processes. To overcome these challenges, an alternate simplified biofuel production scheme was tested based on a cell-free immobilized enzyme system. Using this cell free system, we were able to obtain about 2.6 times higher concentrations of iso-butanol using our non-optimized system as compared with live cell systems. This process involved two steps: (i) converts acid to aldehyde using keto-acid decarboxylase (KdcA), andmore » (ii) produces alcohol from aldehyde using alcohol dehydrogenase (ADH) with a cofactor (NADH) conversion from inexpensive formate using a third enzyme, formate dehydrogenase (FDH). To increase stability and conversion efficiency with easy separations, the first two enzymes were immobilized onto methacrylate resin. Fusion proteins of labile KdcA (fKdcA) were expressed to stabilize the covalently immobilized KdcA. Covalently immobilized ADH exhibited long-term stability and efficient conversion of aldehyde to alcohol over multiple batch cycles without fusions. High conversion rates and low protein leaching were achieved by covalent immobilization of enzymes on methacrylate resin. The complete reaction scheme was demonstrated by immobilizing both ADH and fKdcA and using FDH free in solution. The new system without in situ removal of isobutanol achieved a 55% conversion of ketoisovaleric acid to isobutanol at a concentration of 0.5 % (v/v). Further increases in titer will require continuous removal of the isobutanol using our novel brush membrane system that exhibits a 1.5 fold increase in the separation factor of isobutanol from water versus that obtained for commercial silicone rubber membranes. These bio-inspired brush membranes are based on the presence of glycocalyx filaments coating the luminal surface of our vasculature and represent a new class of synthetic membranes. They thus meet the requirements/scope of the Bimolecular Materials program, Materials Science and Engineering Div., Office of Science, US DOE.« less

Method for conversion of .beta.-hydroxy carbonyl compounds

DOEpatents

Lilga, Michael A.; White, James F.; Holladay, Johnathan E.; Zacher, Alan H.; Muzatko, Danielle S.; Orth, Rick J.

2010-03-30

A process is disclosed for conversion of salts of .beta.-hydroxy carbonyl compounds forming useful conversion products including, e.g., .alpha.,.beta.-unsaturated carbonyl compounds and/or salts of .alpha.,.beta.-unsaturated carbonyl compounds. Conversion products find use, e.g., as feedstock and/or end-use chemicals.

Principles, efficiency, and blueprint character of solar-energy conversion in photosynthetic water oxidation.

PubMed

Dau, Holger; Zaharieva, Ivelina

2009-12-21

Photosynthesis in plants and cyanobacteria involves two protein-cofactor complexes which are denoted as photosystems (PS), PSII and PSI. These solar-energy converters have powered life on earth for approximately 3 billion years. They facilitate light-driven carbohydrate formation from H(2)O and CO(2), by oxidizing the former and reducing the latter. PSII splits water in a process driven by light. Because all attractive technologies for fuel production driven by solar energy involve water oxidation, recent interest in this process carried out by PSII has increased. In this Account, we describe and apply a rationale for estimating the solar-energy conversion efficiency (eta(SOLAR)) of PSII: the fraction of the incident solar energy absorbed by the antenna pigments and eventually stored in form of chemical products. For PSII at high concentrations, approximately 34% of the incident solar energy is used for creation of the photochemistry-driving excited state, P680*, with an excited-state energy of 1.83 eV. Subsequent electron transfer results in the reduction of a bound quinone (Q(A)) and oxidation of the Tyr(Z) within 1 micros. This radical-pair state is stable against recombination losses for approximately 1 ms. At this level, the maximal eta(SOLAR) is 23%. After the essentially irreversible steps of quinone reduction and water oxidation (the final steps catalyzed by the PSII complex), a maximum of 50% of the excited-state energy is stored in chemical form; eta(SOLAR) can be as high as 16%. Extending our considerations to a photosynthetic organism optimized to use PSII and PSI to drive H(2) production, the theoretical maximum of the solar-energy conversion efficiency would be as high as 10.5%, if all electrons and protons derived from water oxidation were used for H(2) formation. The above performance figures are impressive, but they represent theoretical maxima and do not account for processes in an intact organism that lower these yields, such as light saturation, photoinhibitory, protective, and repair processes. The overpotential for catalysis of water oxidation at the Mn(4)Ca complex of PSII may be as low as 0.3 V. To address the specific energetics of water oxidation at the Mn complex of PSII, we propose a new conceptual framework that will facilitate quantitative considerations on the basis of oxidation potentials and pK values. In conclusion, photosynthetic water oxidation works at high efficiency and thus can serve as both an inspiring model and a benchmark in the development of future technologies for production of solar fuels.

A novel process for methanol synthesis. Final report

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

Tierney, J.W.; Wender, I.

1994-01-25

The use of methanol (MeOH) as a fuel additive and in MTBE production has renewed interest in the search for improved MeOH processes. Commercial processes are characterized by high pressures and temperatures with low per pass conversion (10--12%). Efforts are underway to find improved MeOH synthesis processes. A slurry phase ``concurrent`` synthesis of MeOH/methyl formate (MeF) which operates under relatively mild conditions (100{degrees}C lower than present commercial processes) was the subject of investigation in this work. Evidence for a reaction scheme involving the carbonylation of MeOH to MeF followed by the hydrogenolysis of MeF to two molecules of MeOH --more » the net result being the reaction of H{sub 2} with CO to give MeOH via MeF, is presented. Up to 90% per pass conversion and 98% selectivity to methanol at rates comparable to commercial processes have been obtained in spite of the presence of as much as 10,000 ppM CO{sub 2} and 3000 ppM H{sub 2}O in the gas and liquid respectively. The effect of process parameters such as temperature, pressure, H{sub 2}/CO ratio in the reactor, flow rate and catalyst loading were also investigated. The use of temperatures above 170{degrees}C at a pressure of 50 atm results in MeF being the limiting reactant. Small amounts of CH{sub 4} are also formed. Significant MeOH synthesis rates at a pressure in the range of 40--50 atm makes possible the elimination of an upstream shift reactor and the use of an air-blown syngas generator. The nature of the catalysts was studied and correlated with the behavior of the various species in the concurrent synthesis.« less

Use of bovine recombinant prion protein and real-time quaking-induced conversion to detect cattle transmissible mink encephalopathy prions and discriminate classical and atypical L- and H-Type bovine spongiform encephalopathy.

PubMed

Hwang, Soyoun; Greenlee, Justin J; Nicholson, Eric M

2017-01-01

Prions are amyloid-forming proteins that cause transmissible spongiform encephalopathies through a process involving conversion from the normal cellular prion protein to the pathogenic misfolded conformation (PrPSc). This conversion has been used for in vitro assays including serial protein misfolding amplification and real-time quaking induced conversion (RT-QuIC). RT-QuIC can be used for the detection of prions in a variety of biological tissues from humans and animals. Extensive work has been done to demonstrate that RT-QuIC is a rapid, specific, and highly sensitive prion detection assay. RT-QuIC uses recombinant prion protein to detect minute amounts of PrPSc. RT-QuIC has been successfully used to detect PrPSc from different prion diseases with a variety of substrates including hamster, human, sheep, bank vole, bovine and chimeric forms of prion protein. However, recombinant bovine prion protein has not been used to detect transmissible mink encephalopathy (TME) or to differentiate types of bovine spongiform encephalopathy (BSE) in samples from cattle. We evaluated whether PrPSc from TME and BSE infected cattle can be detected with RT-QuIC using recombinant bovine prion proteins, and optimized the reaction conditions to specifically detect cattle TME and to discriminate between classical and atypical BSE by conversion efficiency. We also found that substrate composed of the disease associated E211K mutant protein can be effective for the detection of TME in cattle and that wild type prion protein appears to be a practical substrate to discriminate between the different types of BSEs.

Replacement processes in crystalline rocks

NASA Astrophysics Data System (ADS)

John, Timm; Putnis, Andrew

2010-05-01

A substantial question in metamorphism is what is the mechanism that dominates the conversion of one mineral assemblage to another in response to a change in the ambient physical and/or chemical conditions. Petrological, microstructural, and isotopic data indicate that aqueous fluids must be involved even in the reequilibration of large-scale systems. Fluid-mineral reactions take place by dissolution - precipitation processes, but converting one solid rock to another requires pervasive, either dominantly advective or diffusive fluid-mediated transport through the entire rock. The generation of reaction-induced porosity and the spatial and temporal coupling of dissolution and precipitation can account for fluid and element transport through rocks and the replacement of one mineral assemblage by another. To determine the mechanism of metamorphic reactions we refer to examples of interfaces and reaction textures which contain both the "before" (precursor) and "after" mineral assemblages - case studies where the process of conversion is frozen in. We will illustrate some aspects of the role of fluids in metamorphic reactions and discuss how reactive fluids can pervasively infiltrate a rock. The examples we will use are focussed on crystalline rocks and include reactions from the lower continental crust, the subducting oceanic crust, and the continental upper crust to show that except at very high-temperature conditions, essentially the same mechanisms are responsible for converting rocks to thermodynamically more stable mineral assemblages for given Pressure-Temperature-fluid composition (P-T-X) conditions.

Organic solar cells: understanding the role of Förster resonance energy transfer.

PubMed

Feron, Krishna; Belcher, Warwick J; Fell, Christopher J; Dastoor, Paul C

2012-12-12

Organic solar cells have the potential to become a low-cost sustainable energy source. Understanding the photoconversion mechanism is key to the design of efficient organic solar cells. In this review, we discuss the processes involved in the photo-electron conversion mechanism, which may be subdivided into exciton harvesting, exciton transport, exciton dissociation, charge transport and extraction stages. In particular, we focus on the role of energy transfer as described by F¨orster resonance energy transfer (FRET) theory in the photoconversion mechanism. FRET plays a major role in exciton transport, harvesting and dissociation. The spectral absorption range of organic solar cells may be extended using sensitizers that efficiently transfer absorbed energy to the photoactive materials. The limitations of F¨orster theory to accurately calculate energy transfer rates are discussed. Energy transfer is the first step of an efficient two-step exciton dissociation process and may also be used to preferentially transport excitons to the heterointerface, where efficient exciton dissociation may occur. However, FRET also competes with charge transfer at the heterointerface turning it in a potential loss mechanism. An energy cascade comprising both energy transfer and charge transfer may aid in separating charges and is briefly discussed. Considering the extent to which the photo-electron conversion efficiency is governed by energy transfer, optimisation of this process offers the prospect of improved organic photovoltaic performance and thus aids in realising the potential of organic solar cells.

Analysis of vibrational response in graphite oxide nanoplatelets

NASA Astrophysics Data System (ADS)

Prias Barragan, Jhon Jairo; Gross, Katherine; Lajaunie, Luc; Arenal, Raul; Ariza Calderon, Hernando; Prieto, Pedro

In this work, we present a new low-cost fabrication process to obtain graphite oxide nanoplatelets from bamboo pyroligneous acid (GO-BPA) by thermal decomposition method using a pyrolysis system for different carbonization temperatures from 673 to 973 K. The GO-BPA samples were characterized by using Raman, FTIR, XRD, SEM and TEM techniques, whose results suggest that increased carbonization temperature increases graphite conversion, boundary defects, desorption of some organic compounds and phonon response, respectively. We discuss potential applications of the GO-BPA samples involving phonon response that would benefit from a fully scaled technology, advanced electronic sensors and devices.

Solar prediction and intelligent machines

NASA Technical Reports Server (NTRS)

Johnson, Gordon G.

1987-01-01

The solar prediction program is aimed at reducing or eliminating the need to throughly understand the process previously developed and to still be able to produce a prediction. Substantial progress was made in identifying the procedures to be coded as well as testing some of the presently coded work. Another project involves work on developing ideas and software that should result in a machine capable of learning as well as carrying on an intelligent conversation over a wide range of topics. The underlying idea is to use primitive ideas and construct higher order ideas from these, which can then be easily related one to another.

Numerical simulation of waste tyres gasification.

PubMed

Janajreh, Isam; Raza, Syed Shabbar

2015-05-01

Gasification is a thermochemical pathway used to convert carbonaceous feedstock into syngas (CO and H2) in a deprived oxygen environment. The process can accommodate conventional feedstock such as coal, discarded waste including plastics, rubber, and mixed waste owing to the high reactor temperature (1000 °C-1600 °C). Pyrolysis is another conversion pathway, yet it is more selective to the feedstock owing to the low process temperature (350 °C-550 °C). Discarded tyres can be subjected to pyrolysis, however, the yield involves the formation of intermediate radicals additional to unconverted char. Gasification, however, owing to the higher temperature and shorter residence time, is more opted to follow quasi-equilibrium and being predictive. In this work, tyre crumbs are subjected to two levels of gasification modelling, i.e. equilibrium zero dimension and reactive multi-dimensional flow. The objective is to investigate the effect of the amount of oxidising agent on the conversion of tyre granules and syngas composition in a small 20 kW cylindrical gasifier. Initially the chemical compositions of several tyre samples are measured following the ASTM procedures for proximate and ultimate analysis as well as the heating value. The measured data are used to carry out equilibrium-based and reactive flow gasification. The result shows that both models are reasonably predictive averaging 50% gasification efficiency, the devolatilisation is less sensitive than the char conversion to the equivalence ratio as devolatilisation is always complete. In view of the high attained efficiency, it is suggested that the investigated tyre gasification system is economically viable. © The Author(s) 2015.

Nitrous acid chemistry in Los Angeles during the CalNex-LA experiment

NASA Astrophysics Data System (ADS)

Stutz, J.; Tsai, C.; Wong, K.; Pikelnaya, O.; Hurlock, S. C.; Young, C. J.; Veres, P. R.; Washenfelder, R. A.; Brown, S. S.; Flynn, J. H.; Grossberg, N.; Lefer, B. L.

2011-12-01

The role of nitrous acid, HONO, as an OH radical precursor during the early morning and during the day has received considerable attention over the past decade. Several studies have reported that HONO photolysis in the polluted boundary layer is the dominant source of OH in the early morning, and that it contributes up to 30% to the diurnally averaged primary OH formation. Despite the importance of HONO for boundary layer chemistry, our understanding of HONO sources is still incomplete. Laboratory studies suggest that HONO is formed by the conversion of NO2 on humid surfaces at night. As this process is too slow during the day, several photo-enhanced processes have been proposed that either accelerate the NO2 conversion, or involve other nitrogen species, such as HNO3. Field observations of vertical HONO and NO2 concentration profiles, together with accurate measurements of other nitrogen species and actinic flux measurements offer a unique opportunity to constrain the proposed HONO formation mechanisms. Here we present observations of HONO, NO2, and other parameters made by various instruments during the 2010 CalNex experiment on the east side of the Los Angeles basin. We will discuss the vertical profiles of HONO and NO2 measured by LP-DOAS, CEAS, CIMS, and photolytic conversion + CL with regard to the formation of HONO. The observations will be compared to 1D chemistry and transport model calculations to test various proposed formation mechanisms. We will discuss the most likely formation pathway of HONO and the potential impact of HONO on atmospheric chemistry in Los Angeles.

Structural Conversion of Aβ17–42 Peptides from Disordered Oligomers to U-Shape Protofilaments via Multiple Kinetic Pathways

PubMed Central

Cheon, Mookyung; Hall, Carol K.; Chang, Iksoo

2015-01-01

Discovering the mechanisms by which proteins aggregate into fibrils is an essential first step in understanding the molecular level processes underlying neurodegenerative diseases such as Alzheimer’s and Parkinson's. The goal of this work is to provide insights into the structural changes that characterize the kinetic pathways by which amyloid-β peptides convert from monomers to oligomers to fibrils. By applying discontinuous molecular dynamics simulations to PRIME20, a force field designed to capture the chemical and physical aspects of protein aggregation, we have been able to trace out the entire aggregation process for a system containing 8 Aβ17–42 peptides. We uncovered two fibrillization mechanisms that govern the structural conversion of Aβ17–42 peptides from disordered oligomers into protofilaments. The first mechanism is monomeric conversion templated by a U-shape oligomeric nucleus into U-shape protofilament. The second mechanism involves a long-lived and on-pathway metastable oligomer with S-shape chains, having a C-terminal turn, en route to the final U-shape protofilament. Oligomers with this C-terminal turn have been regarded in recent experiments as a major contributing element to cell toxicity in Alzheimer’s disease. The internal structures of the U-shape protofilaments from our PRIME20/DMD simulation agree well with those from solid state NMR experiments. The approach presented here offers a simple molecular-level framework to describe protein aggregation in general and to visualize the kinetic evolution of a putative toxic element in Alzheimer’s disease in particular. PMID:25955249

Thyroid Hormone and Seasonal Rhythmicity

PubMed Central

Dardente, Hugues; Hazlerigg, David G.; Ebling, Francis J. P.

2014-01-01

Living organisms show seasonality in a wide array of functions such as reproduction, fattening, hibernation, and migration. At temperate latitudes, changes in photoperiod maintain the alignment of annual rhythms with predictable changes in the environment. The appropriate physiological response to changing photoperiod in mammals requires retinal detection of light and pineal secretion of melatonin, but extraretinal detection of light occurs in birds. A common mechanism across all vertebrates is that these photoperiod-regulated systems alter hypothalamic thyroid hormone (TH) conversion. Here, we review the evidence that a circadian clock within the pars tuberalis of the adenohypophysis links photoperiod decoding to local changes of TH signaling within the medio-basal hypothalamus (MBH) through a conserved thyrotropin/deiodinase axis. We also focus on recent findings which indicate that, beyond the photoperiodic control of its conversion, TH might also be involved in longer-term timing processes of seasonal programs. Finally, we examine the potential implication of kisspeptin and RFRP3, two RF-amide peptides expressed within the MBH, in seasonal rhythmicity. PMID:24616714

Small signal analysis of four-wave mixing in InAs/GaAs quantum-dot semiconductor optical amplifiers

NASA Astrophysics Data System (ADS)

Ma, Shaozhen; Chen, Zhe; Dutta, Niloy K.

2009-02-01

A model to study four-wave mixing (FWM) wavelength conversion in InAs-GaAs quantum-dot semiconductor optical amplifier is proposed. Rate equations involving two QD states are solved to simulate the carrier density modulation in the system, results show that the existence of QD excited state contributes to the ultra fast recover time for single pulse response by serving as a carrier reservoir for the QD ground state, its speed limitations are also studied. Nondegenerate four-wave mixing process with small intensity modulation probe signal injected is simulated using this model, a set of coupled wave equations describing the evolution of all frequency components in the active region of QD-SOA are derived and solved numerically. Results show that better FWM conversion efficiency can be obtained compared with the regular bulk SOA, and the four-wave mixing bandwidth can exceed 1.5 THz when the detuning between pump and probe lights is 0.5 nm.

Optical charge state control of spin defects in 4H-SiC

DOE PAGES

Wolfowicz, Gary; Anderson, Christopher P.; Yeats, Andrew L.; ...

2017-11-30

Defects in silicon carbide (SiC) have emerged as a favorable platform for optically active spin-based quantum technologies. Spin qubits exist in specific charge states of these defects, where the ability to control these states can provide enhanced spin-dependent readout and long-term charge stability. We investigate this charge state control for two major spin qubits in 4H-SiC, the divacancy and silicon vacancy, obtaining bidirectional optical charge conversion between the bright and dark states of these defects. We measure increased photoluminescence from divacancy ensembles by up to three orders of magnitude using near-ultraviolet excitation, depending on the substrate, and without degrading themore » electron spin coherence time. This charge conversion remains stable for hours at cryogenic temperatures, allowing spatial and persistent patterning of the charge state populations. As a result, we develop a comprehensive model of the defects and optical processes involved, offering a strong basis to improve material design and to develop quantum applications in SiC.« less

Optical charge state control of spin defects in 4H-SiC

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

Wolfowicz, Gary; Anderson, Christopher P.; Yeats, Andrew L.

Defects in silicon carbide (SiC) have emerged as a favorable platform for optically active spin-based quantum technologies. Spin qubits exist in specific charge states of these defects, where the ability to control these states can provide enhanced spin-dependent readout and long-term charge stability. We investigate this charge state control for two major spin qubits in 4H-SiC, the divacancy and silicon vacancy, obtaining bidirectional optical charge conversion between the bright and dark states of these defects. We measure increased photoluminescence from divacancy ensembles by up to three orders of magnitude using near-ultraviolet excitation, depending on the substrate, and without degrading themore » electron spin coherence time. This charge conversion remains stable for hours at cryogenic temperatures, allowing spatial and persistent patterning of the charge state populations. As a result, we develop a comprehensive model of the defects and optical processes involved, offering a strong basis to improve material design and to develop quantum applications in SiC.« less

Microbial conversion of choline to trimethylamine requires a glycyl radical enzyme

PubMed Central

Craciun, Smaranda; Balskus, Emily P.

2012-01-01

Choline and trimethylamine (TMA) are small molecules that play central roles in biological processes throughout all kingdoms of life. These ubiquitous metabolites are linked through a single biochemical transformation, the conversion of choline to TMA by anaerobic microorganisms. This metabolic activity, which contributes to methanogenesis and human disease, has been known for over a century but has eluded genetic and biochemical characterization. We have identified a gene cluster responsible for anaerobic choline degradation within the genome of a sulfate-reducing bacterium and verified its function using both a genetic knockout strategy and heterologous expression in Escherichia coli. Bioinformatics and electron paramagnetic resonance (EPR) spectroscopy revealed the involvement of a C–N bond cleaving glycyl radical enzyme in TMA production, which is unprecedented chemistry for this enzyme family. Our discovery provides the predictive capabilities needed to identify choline utilization clusters in numerous bacterial genomes, underscoring the importance and prevalence of this metabolic activity within the human microbiota and the environment. PMID:23151509

Underground thermal generation of hydrocarbons from dry, southwestern coals

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

Vanderborgh, N.E.; Elliott, G.R.B.

1978-01-01

The LASL underground coal conversion concept produces intermediate-BTU fuel gas for nearby industries such as ''minemouth'' electric power plants, plus major byproducts in the form of liquid and gaseous hydrocarbons for feedstocks to chemical plants e.g., substitute natural gas (SNG) producers. The concept involves controlling the water influx and drying the coal, generating hydrocarbons, by pyrolysis and finally gasifying the residual char with O/sub 2//CO/sub 2/ or air/CO/sub 2/ mixtures to produce industrial fuel gases. Underground conversion can be frustrated by uncontrolled water in the coal bed. Moisture can (a) prevent combustion, (b) preclude fuel gas formation by lowering reactionmore » zone temperatures and creating kinetic problems, (c) ruin product gas quality by dropping temperatures into a thermodynamically unsatisfactory regime, (d) degrade an initially satisfactory fuel gas by consuming carbon monoxide, (e) waste large amounts of heat, and (f) isolate reaction zones so that the processing will bypass blocks of coal.« less

Artificial photosynthesis: biomimetic approaches to solar energy conversion and storage.

PubMed

Kalyanasundaram, K; Graetzel, M

2010-06-01

Using sun as the energy source, natural photosynthesis carries out a number of useful reactions such as oxidation of water to molecular oxygen and fixation of CO(2) in the form of sugars. These are achieved through a series of light-induced multi-electron-transfer reactions involving chlorophylls in a special arrangement and several other species including specific enzymes. Artificial photosynthesis attempts to reconstruct these key processes in simpler model systems such that solar energy and abundant natural resources can be used to generate high energy fuels and restrict the amount of CO(2) in the atmosphere. Details of few model catalytic systems that lead to clean oxidation of water to H(2) and O(2), photoelectrochemical solar cells for the direct conversion of sunlight to electricity, solar cells for total decomposition of water and catalytic systems for fixation of CO(2) to fuels such as methanol and methane are reviewed here. Copyright 2010 Elsevier Ltd. All rights reserved.

Process for preparing a chemical compound enriched in isotope content

DOEpatents

Michaels, Edward D.

1982-01-01

A process to prepare a chemical enriched in isotope content which includes: (a) A chemical exchange reaction between a first and second compound which yields an isotopically enriched first compound and an isotopically depleted second compound; (b) the removal of a portion of the first compound as product and the removal of a portion of the second compound as spent material; (c) the conversion of the remainder of the first compound to the second compound for reflux at the product end of the chemical exchange reaction region; (d) the conversion of the remainder of the second compound to the first compound for reflux at the spent material end of the chemical exchange region; and the cycling of the additional chemicals produced by one conversion reaction to the other conversion reaction, for consumption therein. One of the conversion reactions is an oxidation reaction, and the energy that it yields is used to drive the other conversion reaction, a reduction. The reduction reaction is carried out in a solid polymer electrolyte electrolytic reactor. The overall process is energy efficient and yields no waste by-products.

More Than One Way to Debrief: A Critical Review of Healthcare Simulation Debriefing Methods.

PubMed

Sawyer, Taylor; Eppich, Walter; Brett-Fleegler, Marisa; Grant, Vincent; Cheng, Adam

2016-06-01

Debriefing is a critical component in the process of learning through healthcare simulation. This critical review examines the timing, facilitation, conversational structures, and process elements used in healthcare simulation debriefing. Debriefing occurs either after (postevent) or during (within-event) the simulation. The debriefing conversation can be guided by either a facilitator (facilitator-guided) or the simulation participants themselves (self-guided). Postevent facilitator-guided debriefing may incorporate several conversational structures. These conversational structures break the debriefing discussion into a series of 3 or more phases to help organize the debriefing and ensure the conversation proceeds in an orderly manner. Debriefing process elements are an array of techniques to optimize reflective experience and maximize the impact of debriefing. These are divided here into the following 3 categories: essential elements, conversational techniques/educational strategies, and debriefing adjuncts. This review provides both novice and advanced simulation educators with an overview of various methods of conducting healthcare simulation debriefing. Future research will investigate which debriefing methods are best for which contexts and for whom, and also explore how lessons from simulation debriefing translate to debriefing in clinical practice.

Development of a peer-review framework for cancer multidisciplinary meetings.

PubMed

Johnson, Claire E; Slavova-Azmanova, Neli; Saunders, Christobel

2017-05-01

There is no mechanism in place for monitoring or quality improvement of cancer multidisciplinary meetings (MDM) in Australia. To develop a peer-review process for quality improvement of MDM. This project involved three phases: (i) development of a draft peer-review framework, supporting documents and peer-review process; (ii) consultation with key stakeholders; (iii) refinement of the framework, documents and processes following a pilot study with three MDM. Feedback indicated that specific standards included in the framework needed to allow the peer reviewers to be flexible relative to the circumstances of the individual MDM. Conversely, feedback identified the need for clear, evidence-based clinical practice guidelines for the conduct of MDM, with accepted standards and objective measures of performance. MDM members were divided about the need to employ peer reviewers from the tumour stream of the MDM under review but agreed that closer involvement of the team under review to support the implementation of recommendations is warranted. We developed an adaptable peer-review framework and process using the current available evidence and guidance. While further research is needed to establish what constitutes best practice in MDM and which processes contribute to improved patient outcomes, the structured peer-review process we describe, when modified using the disease-relevant evidence, could be utilised more broadly as a quality improvement tool. © 2017 Royal Australasian College of Physicians.

Use of enzyme inhibitors to evaluate the conversion pathways of ester and amide prodrugs: a case study example with the prodrug ceftobiprole medocaril.

PubMed

Eichenbaum, Gary; Skibbe, Jennifer; Parkinson, Andrew; Johnson, Mark D; Baumgardner, Dawn; Ogilvie, Brian; Usuki, Etsuko; Tonelli, Fred; Holsapple, Jeff; Schmitt-Hoffmann, Anne

2012-03-01

An approach was developed that uses enzyme inhibitors to support the assessment of the pathways that are responsible for the conversion of intravenously administered ester and amide prodrugs in different biological matrices. The methodology was applied to ceftobiprole medocaril (BAL5788), the prodrug of the cephalosporin antibiotic, ceftobiprole. The prodrug was incubated in plasma, postmitochondrial supernatant fractions from human liver (impaired and nonimpaired), kidney, and intestine as well as erythrocytes, in the presence and absence of different enzyme inhibitors (acetylcholinesterase, pseudocholinesterase, retinyl palmitoyl hydrolase, serine esterases, amidases, and cholinesterase). Hydrolysis was rapid, extensive, and not dependent on the presence of β-nicotinamide-adenine dinucleotide phosphate (reduced form) in all matrices tested, suggesting the involvement of carboxylesterases but not P450 enzymes. Hydrolysis in healthy human plasma was rapid and complete and only partially inhibited in the presence of paraoxonase inhibitors or in liver from hepatic impaired patients, suggesting involvement of nonparaoxonase pathways. The results demonstrate the utility of this approach in confirming the presence of multiple conversion pathways of intravenously administered prodrugs and in the case of BAL5788 demonstrated that this prodrug is unlikely to be affected by genetic polymorphisms, drug interactions, or other environmental factors that might inhibit or induce the enzymes involved in its conversion. Copyright © 2011 Wiley Periodicals, Inc.

Intensifying the Dominant Response II: Nonconscious Negative Affect, Cognitive Demand, and Conversations.

ERIC Educational Resources Information Center

Monahan, Jennifer L.; Laliker, Melanie

2002-01-01

Examines mechanisms that may account for why evaluations made by participants involved in conversations are more influenced by subliminal negative cues than are evaluations made by observers. Explains three studies in which subliminal priming tasks were used with differing cognitive loads and self-preservation concerns among a group of…

Cognition through a Social Network: The Propagation of Induced Forgetting and Practice Effects

ERIC Educational Resources Information Center

Coman, Alin; Hirst, William

2012-01-01

Although a burgeoning literature has shown that practice effects and socially shared retrieval-induced forgetting can reshape the memories of speakers and listeners involved in a conversation, it has generally failed to examine whether such effects can propagate through a sequence of conversational interactions. This lacuna is unfortunate, since…

Contact Us

Science.gov Websites

DUF6 Management and Uses DUF6 Conversion EIS Documents News FAQs Internet Resources Glossary Home  Depleted UF6 Conversion EIS or the Depleted UF6 Management Program web site. Your questions or comments site is to inform and involve the public in the Depleted UF6 Management Program, including the Depleted

Co-Constructing Writing Knowledge: Students' Collaborative Talk across Contexts

ERIC Educational Resources Information Center

Winzenried, Misty Anne; Campbell, Lillian; Chao, Roger; Cardinal, Alison

2017-01-01

Although compositionists recognize that student talk plays an important role in learning to write, there is limited understanding of how students use conversational moves to collaboratively build knowledge about writing across contexts. This article reports on a study of focus group conversations involving first-year students in a cohort program.…

Language Learning: Its Moral and Civic Remit

ERIC Educational Resources Information Center

Williams, Kevin

2017-01-01

The metaphor of education as a conversation that is currently popular is attractive in many respects and it continues to be explored and applied in philosophy of education. This article seeks to consider that aspect of education that involves the literal conversation required to learn other languages. The burden of the argument is that language…

Verbal Repetitions and Echolalia in Alzheimer's Discourse

ERIC Educational Resources Information Center

Da Cruz, Fernanda Miranda

2010-01-01

This article reports on an investigation of echolalic repetition in Alzheimer's disease (AD). A qualitative analysis of data from spontaneous conversations with MHI, a woman with AD, is presented. The data come from the DALI Corpus, a corpus of spontaneous conversations involving subjects with AD. This study argues that echolalic effects can be…

Evaluation of Short-Term Bioassays to Predict Functional Impairment. Selected Short-Term Renal Toxicity Tests.

DTIC Science & Technology

1980-10-01

reported using the method of Gentzkow (1942), which involves conversion of urea to ammonia with urease and measurement of the ammonia by...Nesslerization. Methods employing urease are not well suited for automated analysis since an incubation time of about 20 minutes is required for the conversion of

A Reflective Conversation with Marianne Kuzujanakis M.D.: Intricacies of Giftedness

ERIC Educational Resources Information Center

Shaughnessy, Michael F.

2017-01-01

In this reflective conversation, Marianne Kuzujanakis, a pediatrician and homeschool educator to a profoundly gifted child, discusses her involvement with gifted kids, which began when she approached Supporting Emotional Needs of the Gifted (SENG), a nonprofit gifted support organization. She became fully active in supporting the gifted after her…

"Your Job Is to Take Care of Us": Teaching Our Way through the Boston Marathon Bombings

ERIC Educational Resources Information Center

Bentley, Dana Frantz

2015-01-01

The concept of social justice and critical thinking are prevalent topics in conversations about early childhood education. Usually, critical conversations around these practices tend to involve academics in discussion rather than include practitioners. In today's world, young children are frequently confronted with the realities of violence and…

Before We Get Down to Business: Acquiring Conversational Skills in a Foreign Language.

ERIC Educational Resources Information Center

Kaplan, Marsha A.; Stefanopoulos, Lydie

Because conventional foreign language classroom interaction is not amenable to, and can even undermine, learning of social conversational skills, the Department of State's Foreign Service Institute has created an activity to develop these skills. It involves preparation for and realization of a single event, a party hosted by State Department…

Applying meta-pathway analyses through metagenomics to identify the functional properties of the major bacterial communities of a single spontaneous cocoa bean fermentation process sample.

PubMed

Illeghems, Koen; Weckx, Stefan; De Vuyst, Luc

2015-09-01

A high-resolution functional metagenomic analysis of a representative single sample of a Brazilian spontaneous cocoa bean fermentation process was carried out to gain insight into its bacterial community functioning. By reconstruction of microbial meta-pathways based on metagenomic data, the current knowledge about the metabolic capabilities of bacterial members involved in the cocoa bean fermentation ecosystem was extended. Functional meta-pathway analysis revealed the distribution of the metabolic pathways between the bacterial members involved. The metabolic capabilities of the lactic acid bacteria present were most associated with the heterolactic fermentation and citrate assimilation pathways. The role of Enterobacteriaceae in the conversion of substrates was shown through the use of the mixed-acid fermentation and methylglyoxal detoxification pathways. Furthermore, several other potential functional roles for Enterobacteriaceae were indicated, such as pectinolysis and citrate assimilation. Concerning acetic acid bacteria, metabolic pathways were partially reconstructed, in particular those related to responses toward stress, explaining their metabolic activities during cocoa bean fermentation processes. Further, the in-depth metagenomic analysis unveiled functionalities involved in bacterial competitiveness, such as the occurrence of CRISPRs and potential bacteriocin production. Finally, comparative analysis of the metagenomic data with bacterial genomes of cocoa bean fermentation isolates revealed the applicability of the selected strains as functional starter cultures. Copyright © 2015 Elsevier Ltd. All rights reserved.

Crystal doping aided by rapid expansion of supercritical solutions.

PubMed

Vemavarapu, Chandra; Mollan, Matthew J; Needham, Thomas E

2002-01-01

The purpose of this study was to test the utility of rapid expansion of supercritical solution (RESS) based cocrystallizations in inducing polymorph conversion and crystal disruption of chlorpropamide (CPD). CPD crystals were recrystallized by the RESS process utilizing supercritical carbon dioxide as the solvent. The supercritical region investigated for solute extraction ranged from 45 to 100 degrees C and 2000 to 8000 psi. While pure solute recrystallization formed stage I of these studies, stage II involved recrystallization of CPD in the presence of urea (model impurity). The composition, morphology, and crystallinity of the particles thus produced were characterized utilizing techniques such as microscopy, thermal analysis, x-ray powder diffractometry, and high-performance liquid chromatography. Also, comparative evaluation between RESS and evaporative crystallization from liquid solvents was performed. RESS recrystallizations of commercially available CPD (form A) resulted in polymorph conversion to metastable forms C and V, depending on the temperature and pressure of the recrystallizing solvent. Cocrystallization studies revealed the formation of eutectic mixtures and solid solutions of CPD + urea. Formation of the solid solutions resulted in the crystal disruption of CPD and subsequent amorphous conversion at urea levels higher than 40% wt/wt. Consistent with these results were the reductions in melting point (up to 9 degrees C) and in the DeltaH(f) values of CPD (up to 50%). Scanning electron microscopy revealed a particle size reduction of up to an order of magnitude upon RESS processing. Unlike RESS, recrystallizations from liquid organic solvents lacked the ability to affect polymorphic conversions. Also, the incorporation of urea into the lattice of CPD was found to be inadequate. In providing the ability to control both the particle and crystal morphologies of active pharmaceutical ingredients, RESS proved potentially advantageous to crystal engineering. Rapid crystallization kinetics were found vital in making RESS-based doping superior to conventional solvent-based cocrystallizations.

Mild oxidation of methane to methanol or acetic acid on supported isolated rhodium catalysts

NASA Astrophysics Data System (ADS)

Shan, Junjun; Li, Mengwei; Allard, Lawrence F.; Lee, Sungsik; Flytzani-Stephanopoulos, Maria

2017-11-01

An efficient and direct method of catalytic conversion of methane to liquid methanol and other oxygenates would be of considerable practical value. However, it remains an unsolved problem in catalysis, as typically it involves expensive or corrosive oxidants or reaction media that are not amenable to commercialization. Although methane can be directly converted to methanol using molecular oxygen under mild conditions in the gas phase, the process is either stoichiometric (and therefore requires a water extraction step) or is too slow and low-yielding to be practical. Methane could, in principle, also be transformed through direct oxidative carbonylation to acetic acid, which is commercially obtained through methane steam reforming, methanol synthesis, and subsequent methanol carbonylation on homogeneous catalysts. However, an effective catalyst for the direct carbonylation of methane to acetic acid, which might enable the economical small-scale utilization of natural gas that is currently flared or stranded, has not yet been reported. Here we show that mononuclear rhodium species, anchored on a zeolite or titanium dioxide support suspended in aqueous solution, catalyse the direct conversion of methane to methanol and acetic acid, using oxygen and carbon monoxide under mild conditions. We find that the two products form through independent pathways, which allows us to tune the conversion: three-hour-long batch-reactor tests conducted at 150 degrees Celsius, using either the zeolite-supported or the titanium-dioxide-supported catalyst, yield around 22,000 micromoles of acetic acid per gram of catalyst, or around 230 micromoles of methanol per gram of catalyst, respectively, with selectivities of 60-100 per cent. We anticipate that these unusually high activities, despite still being too low for commercial application, may guide the development of optimized catalysts and practical processes for the direct conversion of methane to methanol, acetic acid and other useful chemicals.

Recent advances in the ITO/InP solar cell

NASA Technical Reports Server (NTRS)

Gessert, T. A.; Li, X.; Wanlass, M. W.; Coutts, T. J.

1991-01-01

It was demonstrated that Indium Tin Oxide (ITO)/InP solar cells can now be made on as-received p(-) bulk substrates which are of nearly equal quality to those which could previously only be made on epitaxially grown p(-) InP base layers. Although this advancement is due in part to both increases in substrate quality and a better understanding of back contact formation, it appears that the passivation/compensation effects resulting from having H2 in the sputtering gas tends to reduce significantly the performance differences previously observed between these two substrates. It is shown that since high efficiency ITO/InP cells can be made from as-received substrates, and since the type conversion process is not highly spatially dependent, large area ITO/InP cells (4 sq cm) with efficiencies approaching 17 percent (Global) can be made. Furthermore, the measured open circuit voltages (V sub OC) and quantum efficiencies (QEs) from these large cells suggest that, when they are processed using optimum grid designs, the efficiencies will be nearly equal to that of the smaller cells thus far produced. It has been shown, through comparative experiments involving ITO/InP and IO/InP cells, that Sn may not be the major cause of type conversion of the InP surface and thus further implies that the ITO may not be an essential element in this type of device. Specifically, very efficient photovoltaic solar cells were made by sputtering (Sn free) In2O3 showing that type conversion and subsequent junction formation will occur even in the absence of the sputtered SN species. The result suggests that sputter damage may indeed be the important mechanism(s) of type conversion. Finally, an initial study of the stability of the ITO/InP cell done over the course of about one year has indicated that the J(sub SC) (short circuit current) and the fill factor (FF) are measurably stable within experimental certainty.

Mild oxidation of methane to methanol or acetic acid on supported isolated rhodium catalysts

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

Shan, Junjun; Li, Mengwei; Allard, Lawrence F.

An efficient and direct method of catalytic conversion of methane to liquid methanol and other oxygenates would be of considerable practical value. However, it remains an unsolved problem in catalysis, as typically it involves expensive or corrosive oxidants or reaction media(5-8) that are not amenable to commercialization. Although methane can be directly converted to methanol using molecular oxygen under mild conditions in the gas phase, the process is either stoichiometric (and therefore requires a water extraction step) or is too slow and low-yielding to be practical. Methane could, in principle, also be transformed through direct oxidative carbonylation to acetic acid,more » which is commercially obtained through methane steam reforming, methanol synthesis, and subsequent methanol carbonylation on homogeneous catalysts. However, an effective catalyst for the direct carbonylation of methane to acetic acid, which might enable the economical small-scale utilization of natural gas that is currently flared or stranded, has not yet been reported. Here we show that mononuclear rhodium species, anchored on a zeolite or titanium dioxide support suspended in aqueous solution, catalyse the direct conversion of methane to methanol and acetic acid, using oxygen and carbon monoxide under mild conditions. Here, we find that the two products form through independent pathways, which allows us to tune the conversion: three-hour-long batch-reactor tests conducted at 150 degrees Celsius, using either the zeolitesupported or the titanium-dioxide-supported catalyst, yield around 22,000 micromoles of acetic acid per gram of catalyst, or around 230 micromoles of methanol per gram of catalyst, respectively, with selectivities of 60-100 per cent. Finally, we anticipate that these unusually high activities, despite still being too low for commercial application, may guide the development of optimized catalysts and practical processes for the direct conversion of methane to methanol, acetic acid and other useful chemicals.« less

Mild oxidation of methane to methanol or acetic acid on supported isolated rhodium catalysts

DOE PAGES

Shan, Junjun; Li, Mengwei; Allard, Lawrence F.; ...

2017-11-30

An efficient and direct method of catalytic conversion of methane to liquid methanol and other oxygenates would be of considerable practical value. However, it remains an unsolved problem in catalysis, as typically it involves expensive or corrosive oxidants or reaction media(5-8) that are not amenable to commercialization. Although methane can be directly converted to methanol using molecular oxygen under mild conditions in the gas phase, the process is either stoichiometric (and therefore requires a water extraction step) or is too slow and low-yielding to be practical. Methane could, in principle, also be transformed through direct oxidative carbonylation to acetic acid,more » which is commercially obtained through methane steam reforming, methanol synthesis, and subsequent methanol carbonylation on homogeneous catalysts. However, an effective catalyst for the direct carbonylation of methane to acetic acid, which might enable the economical small-scale utilization of natural gas that is currently flared or stranded, has not yet been reported. Here we show that mononuclear rhodium species, anchored on a zeolite or titanium dioxide support suspended in aqueous solution, catalyse the direct conversion of methane to methanol and acetic acid, using oxygen and carbon monoxide under mild conditions. Here, we find that the two products form through independent pathways, which allows us to tune the conversion: three-hour-long batch-reactor tests conducted at 150 degrees Celsius, using either the zeolitesupported or the titanium-dioxide-supported catalyst, yield around 22,000 micromoles of acetic acid per gram of catalyst, or around 230 micromoles of methanol per gram of catalyst, respectively, with selectivities of 60-100 per cent. Finally, we anticipate that these unusually high activities, despite still being too low for commercial application, may guide the development of optimized catalysts and practical processes for the direct conversion of methane to methanol, acetic acid and other useful chemicals.« less

Process for carbonaceous material conversion and recovery of alkali metal catalyst constituents held by ion exchange sites in conversion residue

DOEpatents

Sharp, David W.

1980-01-01

In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered for the particles by contacting or washing them with an aqueous solution containing calcium or magnesium ions in an alkali metal recovery zone at a low temperature, preferably below about 249.degree. F. During the washing or leaching process, the calcium or magnesium ions displace alkali metal ions held by ion exchange sites in the particles thereby liberating the ions and producing an aqueous effluent containing alkali metal constituents. The aqueous effluent from the alkali metal recovery zone is then recycled to the conversion process where the alkali metal constituents serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst.

Biochemistry of Suberization

PubMed Central

Agrawal, Vishwanath P.; Kolattukudy, P. E.

1977-01-01

A cell-free extract obtained from suberizing potato (Solanum tuberosum L.) tuber disks catalyzed the conversion of 16-hydroxy[G-3H]hexadecanoic acid to the corresponding dicarboxylic acid with NADP or NAD as the cofactor, with a slight preference for the former. This ω-hydroxyacid dehydrogenase activity, located largely in the 100,000g supernatant fraction, has a pH optimum of 9.5. It showed an apparent Km of 50 μM for 16-hydroxyhexadecanoic acid. The dehydrogenase activity was inhibited by thiol reagents, such as p-chloromercuribenzoate, N-ethylmaleimide, and iodoacetamide, and this dehydrogenase is shown to be different from alcohol dehydrogenase. That 16-oxohexadecanoic acid was an intermediate in the conversion of 16-hydroxyhexadecanoic acid to the corresponding dicarboxylic acid was suggested by the observation that the cell-free extract also catalyzed the conversion of 16-oxohexadecanoic acid to the dicarboxylic acid, with NADP as the preferred cofactor. The time course of development of the ω-hydroxyacid dehydrogenase activity in the suberizing potato disks correlated with the rate of deposition of suberin. Experiments with actinomycin D and cycloheximide suggested that the transcriptional processes, which are directly related to suberin biosynthesis and ω-hydroxyacid dehydrogenase biosynthesis, occurred between 72 and 96 hours after wounding. These results strongly suggest that a wound-induced ω-hydroxyacid dehydrogenase is involved in suberin biosynthesis in potato disks. PMID:16659915

Significant enhancement in the power-conversion efficiency of chlorophyll co-sensitized solar cells by mimicking the principles of natural photosynthetic light-harvesting complexes.

PubMed

Wang, Xiao-Feng; Koyama, Yasushi; Kitao, Osamu; Wada, Yuji; Sasaki, Shin-Ich; Tamiaki, Hitoshi; Zhou, Haoshen

2010-04-15

Dye-sensitized solar cells (DSSCs) are similar to natural photosynthesis in the initial processes involving in light-harvesting and charge separation. In order to mimic those natural photosynthetic systems mainly containing multiple pigments, six different chlorophyllous sensitizers have been isolated from natural photosynthetic organism or synthesized based on natural photosynthetic precursors, and used for fabricating DSSCs. These dye sensitizers can be placed into three classes, i.e., a-type, b-type, or c-type, based on the structural similarity to their analogs of the natural photosynthesis pigments chlorophylls a, b, and c. We succeeded in demonstrating homogeneous co-sensitization among these analogues when these were present together on mesoporous TiO2 films, and we measured the photovoltaic performance of the resulting chlorophyll-sensitized solar cells. Significantly enhanced power-conversion efficiencies (eta) were achieved with DSSCs based on co-sensitization of a chlorophyll a derivative with a chlorophyll b or c derivative. A highest power-conversion efficiency of up to 5.4% has been obtained. These results suggest that it is possible to apply multiple pigments and the energy transfer mechanism from natural photosynthetic systems in fabricating high-efficiency DSSCs. 2010 Elsevier B.V. All rights reserved.

Climate Impact and Economic Feasibility of Solar Thermochemical Jet Fuel Production.

PubMed

Falter, Christoph; Batteiger, Valentin; Sizmann, Andreas

2016-01-05

Solar thermochemistry presents a promising option for the efficient conversion of H2O and CO2 into liquid hydrocarbon fuels using concentrated solar energy. To explore the potential of this fuel production pathway, the climate impact and economic performance are analyzed. Key drivers for the economic and ecological performance are thermochemical energy conversion efficiency, the level of solar irradiation, operation and maintenance, and the initial investment in the fuel production plant. For the baseline case of a solar tower concentrator with CO2 capture from air, jet fuel production costs of 2.23 €/L and life cycle greenhouse gas (LC GHG) emissions of 0.49 kgCO2-equiv/L are estimated. Capturing CO2 from a natural gas combined cycle power plant instead of the air reduces the production costs by 15% but leads to LC GHG emissions higher than that of conventional jet fuel. Favorable assumptions for all involved process steps (30% thermochemical energy conversion efficiency, 3000 kWh/(m(2) a) solar irradiation, low CO2 and heliostat costs) result in jet fuel production costs of 1.28 €/L at LC GHG emissions close to zero. Even lower production costs may be achieved if the commercial value of oxygen as a byproduct is considered.

Community Game Day: Using an End-of-Life Conversation Game to Encourage Advance Care Planning.

PubMed

Van Scoy, Lauren J; Reading, Jean M; Hopkins, Margaret; Smith, Brandi; Dillon, Judy; Green, Michael J; Levi, Benjamin H

2017-11-01

Advance care planning (ACP) is an important process that involves discussing and documenting one's values and preferences for medical care, particularly end-of-life treatments. This convergent, mixed-methods study assessed whether an end-of-life conversation card game is an acceptable and effective means for performing ACP for patients with chronic illness and/or their caregivers when deployed in a community setting. Twenty-two games (n = 93 participants) were held in community settings surrounding Hershey, PA in 2016. Participants were recruited using random sampling from patient databases and also convenience sampling (i.e., flyers). Quantitative questionnaires and qualitative focus group interviews were administered to assess the game experience and subsequent performance of ACP behaviors. Both quantitative and qualitative data found that Community Game Day was a well-received, positive experience for participants and 75% of participants performed ACP within three months post-intervention. These findings suggest that using a conversation game during community outreach is a useful approach for engaging patients and caregivers in ACP. The convergence of quantitative and qualitative data strongly supports the continued investigation of the game in randomized controlled trials. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Method and apparatus for optical encoding with compressible imaging

NASA Technical Reports Server (NTRS)

Leviton, Douglas B. (Inventor)

2006-01-01

The present invention presents an optical encoder with increased conversion rates. Improvement in the conversion rate is a result of combining changes in the pattern recognition encoder's scale pattern with an image sensor readout technique which takes full advantage of those changes, and lends itself to operation by modern, high-speed, ultra-compact microprocessors and digital signal processors (DSP) or field programmable gate array (FPGA) logic elements which can process encoder scale images at the highest speeds. Through these improvements, all three components of conversion time (reciprocal conversion rate)--namely exposure time, image readout time, and image processing time--are minimized.

Inheritance of Crystallographic Orientation during Lithiation/Delithiation Processes of Single-Crystal α-Fe2O3 Nanocubes in Lithium-Ion Batteries.

PubMed

Ma, Xiaowei; Zhang, Manyu; Liang, Chongyun; Li, Yuesheng; Wu, Jingjing; Che, Renchao

2015-11-04

Iron oxides are very promising anode materials based on conversion reactions for lithium-ion batteries (LIBs). During conversion processes, the crystal structure and composition of the electrode material are drastically changed. Surprisingly, in our study, inheritance of a crystallographic orientation was found during lithiation/delithiation processes of single-crystal α-Fe2O3 nanocubes by ex situ transmission electron microscopy. Single-crystal α-Fe2O3 was first transformed into numerous Fe nanograins embedded in a Li2O matrix, and then the conversion between Fe and FeO nanograins became the main reversible electrochemical reaction for energy storage. Interestingly, these Fe/FeO nanograins had almost the same crystallographic orientation, indicating that the lithiated/delithiated products can inherit the crystallographic orientation of single-crystal α-Fe2O3. This finding is important for understanding the detailed electrochemical conversion processes of iron oxides, and this feature may also exist during lithiation/delithiation processes of other transition-metal oxides.

Keeping Control: The Role of Senescence and Development in Plant Pathogenesis and Defense

PubMed Central

Häffner, Eva; Konietzki, Sandra; Diederichsen, Elke

2015-01-01

Many plant pathogens show interactions with host development. Pathogens may modify plant development according to their nutritional demands. Conversely, plant development influences pathogen growth. Biotrophic pathogens often delay senescence to keep host cells alive, and resistance is achieved by senescence-like processes in the host. Necrotrophic pathogens promote senescence in the host, and preventing early senescence is a resistance strategy of plants. For hemibiotrophic pathogens both patterns may apply. Most signaling pathways are involved in both developmental and defense reactions. Increasing knowledge about the molecular components allows to distinguish signaling branches, cross-talk and regulatory nodes that may influence the outcome of an infection. In this review, recent reports on major molecular players and their role in senescence and in pathogen response are reviewed. Examples of pathosystems with strong developmental implications illustrate the molecular basis of selected control strategies. A study of gene expression in the interaction between the hemibiotrophic vascular pathogen Verticillium longisporum and its cruciferous hosts shows processes that are fine-tuned to counteract early senescence and to achieve resistance. The complexity of the processes involved reflects the complex genetic control of quantitative disease resistance, and understanding the relationship between disease, development and resistance will support resistance breeding. PMID:27135337

Quantifying electron transfer reactions in biological systems: what interactions play the major role?

NASA Astrophysics Data System (ADS)

Sjulstok, Emil; Olsen, Jógvan Magnus Haugaard; Solov'Yov, Ilia A.

2015-12-01

Various biological processes involve the conversion of energy into forms that are usable for chemical transformations and are quantum mechanical in nature. Such processes involve light absorption, excited electronic states formation, excitation energy transfer, electrons and protons tunnelling which for example occur in photosynthesis, cellular respiration, DNA repair, and possibly magnetic field sensing. Quantum biology uses computation to model biological interactions in light of quantum mechanical effects and has primarily developed over the past decade as a result of convergence between quantum physics and biology. In this paper we consider electron transfer in biological processes, from a theoretical view-point; namely in terms of quantum mechanical and semi-classical models. We systematically characterize the interactions between the moving electron and its biological environment to deduce the driving force for the electron transfer reaction and to establish those interactions that play the major role in propelling the electron. The suggested approach is seen as a general recipe to treat electron transfer events in biological systems computationally, and we utilize it to describe specifically the electron transfer reactions in Arabidopsis thaliana cryptochrome-a signaling photoreceptor protein that became attractive recently due to its possible function as a biological magnetoreceptor.

Everyday conversation requires cognitive inference: neural bases of comprehending implicated meanings in conversations.

PubMed

Jang, Gijeong; Yoon, Shin-ae; Lee, Sung-Eun; Park, Haeil; Kim, Joohan; Ko, Jeong Hoon; Park, Hae-Jeong

2013-11-01

In ordinary conversations, literal meanings of an utterance are often quite different from implicated meanings and the inference about implicated meanings is essentially required for successful comprehension of the speaker's utterances. Inference of finding implicated meanings is based on the listener's assumption that the conversational partner says only relevant matters according to the maxim of relevance in Grice's theory of conversational implicature. To investigate the neural correlates of comprehending implicated meanings under the maxim of relevance, a total of 23 participants underwent an fMRI task with a series of conversational pairs, each consisting of a question and an answer. The experimental paradigm was composed of three conditions: explicit answers, moderately implicit answers, and highly implicit answers. Participants were asked to decide whether the answer to the Yes/No question meant 'Yes' or 'No'. Longer reaction time was required for the highly implicit answers than for the moderately implicit answers without affecting the accuracy. The fMRI results show that the left anterior temporal lobe, left angular gyrus, and left posterior middle temporal gyrus had stronger activation in both moderately and highly implicit conditions than in the explicit condition. Comprehension of highly implicit answers had increased activations in additional regions including the left inferior frontal gyrus, left medial prefrontal cortex, left posterior cingulate cortex and right anterior temporal lobe. The activation results indicate involvement of these regions in the inference process to build coherence between literally irrelevant but pragmatically associated utterances under the maxim of relevance. Especially, the left anterior temporal lobe showed high sensitivity to the level of implicitness and showed increased activation for highly versus moderately implicit conditions, which imply its central role in inference such as semantic integration. The right hemisphere activation, uniquely found in the anterior temporal lobe for highly implicit utterances, suggests its competence for integrating distant concepts in implied utterances under the relevance principle. Copyright © 2013 Elsevier Inc. All rights reserved.

A real time spectrum to dose conversion system

NASA Technical Reports Server (NTRS)

Farmer, B. J.; Johnson, J. H.; Bagwell, R. G.

1972-01-01

A system has been developed which permits the determination of dose in real time or near real time directly from the pulse-height output of a radiation spectrometer. The technique involves the use of the resolution matrix of a spectrometer, the radiation energy-to-dose conversion function, and the geometrical factors, although the order of matrix operations is reversed. The new technique yields a result which is mathematically identical to the standard method while requiring no matrix manipulations or resolution matrix storage in the remote computer. It utilizes only a single function for each type dose required and each geometric factor involved.

The spread of prion-like proteins by lysosomes and tunneling nanotubes: Implications for neurodegenerative diseases.

PubMed

Victoria, Guiliana Soraya; Zurzolo, Chiara

2017-09-04

Progression of pathology in neurodegenerative diseases is hypothesized to be a non-cell-autonomous process that may be mediated by the productive spreading of prion-like protein aggregates from a "donor cell" that is the source of misfolded aggregates to an "acceptor cell" in which misfolding is propagated by conversion of the normal protein. Although the proteins involved in the various diseases are unrelated, common pathways appear to be used for their intercellular propagation and spreading. Here, we summarize recent evidence of the molecular mechanisms relevant for the intercellular trafficking of protein aggregates involved in prion, Alzheimer's, Huntington's, and Parkinson's diseases. We focus in particular on the common roles that lysosomes and tunneling nanotubes play in the formation and spreading of prion-like assemblies. © 2017 Victoria and Zurzolo.

The spread of prion-like proteins by lysosomes and tunneling nanotubes: Implications for neurodegenerative diseases

PubMed Central

Victoria, Guiliana Soraya

2017-01-01

Progression of pathology in neurodegenerative diseases is hypothesized to be a non–cell-autonomous process that may be mediated by the productive spreading of prion-like protein aggregates from a “donor cell” that is the source of misfolded aggregates to an “acceptor cell” in which misfolding is propagated by conversion of the normal protein. Although the proteins involved in the various diseases are unrelated, common pathways appear to be used for their intercellular propagation and spreading. Here, we summarize recent evidence of the molecular mechanisms relevant for the intercellular trafficking of protein aggregates involved in prion, Alzheimer’s, Huntington’s, and Parkinson’s diseases. We focus in particular on the common roles that lysosomes and tunneling nanotubes play in the formation and spreading of prion-like assemblies. PMID:28724527

Armored Enzyme Nanoparticles for Remediation of Subsurface

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

Grate, Jay W.

2005-09-01

The remediation of subsurface contaminants is a critical problem for the Department of Energy, other government agencies, and our nation. Severe contamination of soil and groundwater exists at several DOE sites due to various methods of intentional and unintentional release. Given the difficulties involved in conventional removal or separation processes, it is vital to develop methods to transform contaminants and contaminated earth/water to reduce risks to human health and the environment. Transformation of the contaminants themselves may involve conversion to other immobile species that do not migrate into well water or surface waters, as is proposed for metals and radionuclides;more » or degradation to harmless molecules, as is desired for organic contaminants. Transformation of contaminated earth (as opposed to the contaminants themselves) may entail reductions in volume or release of bound contaminants for remediation.« less

Detoxification of biomass derived acetate via metabolic conversion to ethanol, acetone, isopropanol, or ethyl acetate

DOEpatents

Sillers, William Ryan; Van Dijken, Hans; Licht, Steve; Shaw, IV, Arthur J.; Gilbert, Alan Benjamin; Argyros, Aaron; Froehlich, Allan C.; McBride, John E.; Xu, Haowen; Hogsett, David A.; Rajgarhia, Vineet B.

2017-03-28

One aspect of the invention relates to a genetically modified thermophilic or mesophilic microorganism, wherein a first native gene is partially, substantially, or completely deleted, silenced, inactivated, or down-regulated, which first native gene encodes a first native enzyme involved in the metabolic production of an organic acid or a salt thereof, thereby increasing the native ability of said thermophilic or mesophilic microorganism to produce lactate or acetate as a fermentation product. In certain embodiments, the aforementioned microorganism further comprises a first non-native gene, which first non-native gene encodes a first non-native enzyme involved in the metabolic production of lactate or acetate. Another aspect of the invention relates to a process for converting lignocellulosic biomass to lactate or acetate, comprising contacting lignocellulosic biomass with a genetically modified thermophilic or mesophilic microorganism.

Educational Design as Conversation: A Conversation Analytical Perspective on Teacher Dialogue

ERIC Educational Resources Information Center

van Kruiningen, Jacqueline F.

2013-01-01

The aim of this methodological paper is to expound on and demonstrate the value of conversation-analytical research in the area of (informal) teacher learning. The author discusses some methodological issues in current research on interaction in teacher learning and holds a plea for conversation-analytical research on interactional processes in…

Forest-land conversion, ecosystem services, and economic issues for policy: a review

Treesearch

Robert A. Smail; David J. Lewis

2009-01-01

The continued conversion and development of forest land pose a serious threat to the ecosystem services derived from forested landscapes. We argue that developing an understanding of the full range of consequences from forest conversion requires understanding the effects of such conversion on both components of ecosystem services: products and processes....

How Ag Nanospheres Are Transformed into AgAu Nanocages

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

Moreau, Liane M.; Schurman, Charles A.; Kewalramani, Sumit

Bimetallic hollow, porous noble metal nanoparticles are of broad interest for biomedical, optical and catalytic applications. The most straightforward method for preparing such structures involves the reaction between HAuCl4 and well-formed Ag particles, typically spheres, cubes, or triangular prisms, yet the mechanism underlying their formation is poorly understood at the atomic scale. By combining in situ nanoscopic and atomic-scale characterization techniques (XAFS, SAXS, XRF, and electron microscopy) to follow the process, we elucidate a plausible reaction pathway for the conversion of citrate-capped Ag nanospheres to AgAu nanocages; importantly, the hollowing event cannot be explained by the nanoscale Kirkendall effect, normore » by Galvanic exchange alone, two processes that have been previously proposed. We propose a modification of the bulk Galvanic exchange process that takes into account considerations that can only occur with nanoscale particles. This nanoscale Galvanic exchange process explains the novel morphological and chemical changes associated with the typically observed hollowing process.« less

An oscillator model of the timing of turn-taking.

PubMed

Wilson, Margaret; Wilson, Thomas P

2005-12-01

When humans talk without conventionalized arrangements, they engage in conversation--that is, a continuous and largely nonsimultaneous exchange in which speakers take turns. Turn-taking is ubiquitous in conversation and is the normal case against which alternatives, such as interruptions, are treated as violations that warrant repair. Furthermore, turn-taking involves highly coordinated timing, including a cyclic rise and fall in the probability of initiating speech during brief silences, and involves the notable rarity, especially in two-party conversations, of two speakers' breaking a silence at once. These phenomena, reported by conversation analysts, have been neglected by cognitive psychologists, and to date there has been no adequate cognitive explanation. Here, we propose that, during conversation, endogenous oscillators in the brains of the speaker and the listeners become mutually entrained, on the basis of the speaker's rate of syllable production. This entrained cyclic pattern governs the potential for initiating speech at any given instant for the speaker and also for the listeners (as potential next speakers). Furthermore, the readiness functions of the listeners are counterphased with that of the speaker, minimizing the likelihood of simultaneous starts by a listener and the previous speaker. This mutual entrainment continues for a brief period when the speech stream ceases, accounting for the cyclic property of silences. This model not only captures the timing phenomena observed inthe literature on conversation analysis, but also converges with findings from the literatures on phoneme timing, syllable organization, and interpersonal coordination.

Atomistic Conversion Reaction Mechanism of WO 3 in Secondary Ion Batteries of Li, Na, and Ca

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

He, Yang; Gu, Meng; Xiao, Haiyan

2016-04-13

Reversible insertion and extraction of ionic species into a host lattice governs the basic operating principle for both rechargeable battery (such as lithium batteries) and electrochromic devices (such as ANA Boeing 787-8 Dreamliner electrochromic window). Intercalation and/or conversion are two fundamental chemical processes for some materials in response to the ion insertion. The interplay between these two chemical processes has never been established. It is speculated that the conversion reaction is initiated by ion intercalation. However, experimental evidence of intercalation and subsequent conversion remains unexplored. Here, using in situ HRTEM and spectroscopy, we captured the atomistic conversion reaction processes duringmore » lithium, sodium and calcium ion insertion into tungsten trioxide (WO3) single crystal model electrodes. An intercalation step right prior to conversion is explicitly revealed at atomic scale for the first time for these three ion species. Combining nanoscale diffraction and ab initio molecular dynamics simulations, it is found that, beyond intercalation, the inserted ion-oxygen bonding formation destabilized the transition-metal framework which gradually shrunk, distorted and finally collapsed to a pseudo-amorphous structure. This study provides a full atomistic picture on the transition from intercalation to conversion, which is of essential for material applications in both secondary ion batteries and electrochromic devices.« less

Cathecol-O-methyl transferase Val158Met genotype is not a risk factor for conversion disorder.

PubMed

Armagan, E; Almacıoglu, M L; Yakut, T; Köse, A; Karkucak, M; Köksal, O; Görükmez, O

2013-03-19

Alterations in catechol-O-methyltransferase (COMT) activity are involved in various types of neurological disorders. We examined a possible association between the COMT Val158Met polymorphism and conversion disorder in a study of 48 patients with conversion disorder and 48 control patients. In the conversion disorder group, 31 patients were Val/Met heterozygotes, 15 patients were Val/Val homozygotes and 2 patients were Met/Met homozygotes. In the control group, 32 patients were Val/Met heterozygotes and 16 patients were Val/Val homozygotes. There was no significant difference between the groups. We conclude that the COMT Val158Met genotype is quite common in Turkey and that it is not a risk factor for conversion disorder in the Turkish population.

Conversion of Carbon Dioxide into Ethanol by Electrochemical Synthesis Method Using Cu-Zn Electrode

NASA Astrophysics Data System (ADS)

Riyanto; Ramadan, S.; Fariduddin, S.; Aminudin, A. R.; Hayatri, A. K.

2018-01-01

Research on conversion of carbon dioxide into ethanol has been done. The conversion process is carried out in a sodium bicarbonate electrolyte solution in an electrochemical synthesis reactor. As cathode was used Cu-Zn, while as anode carbon was utilized. Variations of voltage, concentration of sodium bicarbonate electrolyte solution and time of electrolysis were performed to determine the optimum conditions to convert carbon dioxide into ethanol. Sample of the electrochemical synthesis process was analyzed by gas chromatography. From the result, it is found that the optimum conditions of the electrochemical synthesis process of carbon dioxide conversion into ethanol are voltage, concentration of sodium bicarbonate electrolyte solution and time of electrolysis are 3 volts, 0.4 M and 90 minutes with the ethanol concentration of 10.44%.

What can paper-based clinical information systems tell us about the design of computerized clinical information systems (CIS) in the ICU?

PubMed

Miller, A; Pilcher, D; Mercaldo, N; Leong, T; Scheinkestel, C; Schildcrout, J

2010-08-01

Screen designs in computerized clinical information systems (CIS) have been modeled on their paper predecessors. However, limited understanding about how paper forms support clinical work means that we risk repeating old mistakes and creating new opportunities for error and inefficiency as illustrated by problems associated with computerized provider order entry systems. This study was designed to elucidate principles underlying a successful ICU paper-based CIS. The research was guided by two exploratory hypotheses: (1) paper-based artefacts (charts, notes, equipment, order forms) are used differently by nurses, doctors and other healthcare professionals in different (formal and informal) conversation contexts and (2) different artefacts support different decision processes that are distributed across role-based conversations. All conversations undertaken at the bedsides of five patients were recorded with any supporting artefacts for five days per patient. Data was coded according to conversational role-holders, clinical decision process, conversational context and artefacts. 2133 data points were analyzed using Poisson logistic regression analyses. Results show significant interactions between artefacts used during different professional conversations in different contexts (chi(2)((df=16))=55.8, p<0.0001). The interaction between artefacts used during different professional conversations for different clinical decision processes was not statistically significant although all two-way interactions were statistically significant. Paper-based CIS have evolved to support complex interdisciplinary decision processes. The translation of two design principles - support interdisciplinary perspectives and integrate decision processes - from paper to computerized CIS may minimize the risks associated with computerization. 2010 Australian College of Critical Care Nurses Ltd. Published by Elsevier Ltd. All rights reserved.

Carbothermic Synthesis of 820 m UN Kernels: Literature Review, Thermodynamics, Analysis, and Related Experiments

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

Lindemer, Terrence; Voit, Stewart L; Silva, Chinthaka M

2014-01-01

The U.S. Department of Energy is considering a new nuclear fuel that would be less susceptible to ruptures during a loss-of-coolant accident. The fuel would consist of tristructural isotropic coated particles with large, dense uranium nitride (UN) kernels. This effort explores many factors involved in using gel-derived uranium oxide-carbon microspheres to make large UN kernels. Analysis of recent studies with sufficient experimental details is provided. Extensive thermodynamic calculations are used to predict carbon monoxide and other pressures for several different reactions that may be involved in conversion of uranium oxides and carbides to UN. Experimentally, the method for making themore » gel-derived microspheres is described. These were used in a microbalance with an attached mass spectrometer to determine details of carbothermic conversion in argon, nitrogen, or vacuum. A quantitative model is derived from experiments for vacuum conversion to an uranium oxide-carbide kernel.« less

Comparative studies of thin film growth on aluminium by AFM, TEM and GDOES characterization

NASA Astrophysics Data System (ADS)

Qi, Jiantao; Thompson, George E.

2016-07-01

In this present study, comparative studies of trivalent chromium conversion coating formation, associated with aluminium dissolution process, have been investigated using atomic force microscopy (AFM), transmission electron microscopy (TEM) and glow-discharge optical emission spectroscopy (GDOES). High-resolution electron micrographs revealed the evident and uniform coating initiation on the whole surface after conversion treatment for only 30 s, although a network of metal ridges was created by HF etching pre-treatment. In terms of conversion treatment process on electropolished aluminium, constant kinetics of coating growth, ∼0.30 ± 0.2 nm/s, were found after the prolonged conversion treatment for 600 s. The availability of electrolyte anions for coating deposition determined the growth process. Simultaneously, a proceeding process of aluminium dissolution during conversion treatment, of ∼0.11 ± 0.02 nm/s, was found for the first time, indicating constant kinetics of anodic reactions. The distinct process of aluminium consumption was assigned with loss of corrosion protection of the deposited coating material as evidenced in the electrochemical impedance spectroscopy. Based on the present data, a new mechanism of coating growth on aluminium was proposed, and it consisted of an activation period (0-30 s), a linear growth period (0.30 nm/s, up for 600 s) and limited growth period (0.17 nm/s, 600-1200 s). In addition, the air-drying post-treatment and a high-vacuum environment in the microscope revealed a coating shrinkage, especially in the coatings after conversion treatments for longer time.

Managing Conversations: The Medium for Achieving "Breakthrough" Results.

ERIC Educational Resources Information Center

Bolton, Robert

1998-01-01

Unlike traditional management development, use of conversations in coaching high-performance work teams addresses core processes of speaking and listening. Management of conversations aims to create learning that will lead to breakthroughs in team performance. (SK)

Biological Solar Energy Conversion and U.S. Energy Policy

ERIC Educational Resources Information Center

Pimentel, David; And Others

1978-01-01

Surveys energy consumption in the United States and explores the possibility of increasing the amount of energy obtained from biomass conversion (biologically produced energy). Economic and environmental concerns of biomass conversion processes are discussed. (CP)

Power efficiency improvements of the industrial processes at application of thermochemical recuperation of heath of the leaving gases with use of microchannel reactors

NASA Astrophysics Data System (ADS)

Tararykov, A. V.; Garyaev, A. B.

2017-11-01

The possibility of increasing the energy efficiency of production processes by converting the initial fuel - natural gas to synthesized fuel using the heat of the exhaust gases of plants involved in production is considered. Possible applications of this technology are given. A mathematical model of the processes of heat and mass transfer occurring in a thermochemical reactor is developed taking into account the nonequilibrium nature of the course of chemical reactions of fuel conversion. The possibility of using microchannel reaction elements and facilities for methane conversion in order to intensify the process and reduce the overall dimensions of plants is considered. The features of the course of heat and mass transfer processes under flow conditions in microchannel reaction elements are described. Additions have been made to the mathematical model, which makes it possible to use it for microchannel installations. With the help of a mathematical model, distribution of the parameters of mixtures along the length of the reaction element of the reactor-temperature, the concentration of the reacting components, the velocity, and the values of the heat fluxes are obtained. The calculations take into account the change in the thermophysical properties of the mix-ture, the type of the catalytic element, the rate of the reactions, the heat exchange processes by radiation, and the lon-gitudinal heat transfer along the flow of the reacting mixture. The reliability of the results of the application of the mathematical model is confirmed by their comparison with the experimental data obtained by Grasso G., Schaefer G., Schuurman Y., Mirodatos C., Kuznetsov V.V., Vitovsky O.V. on similar installations.

Property evolution during vitrification of dimethacrylate photopolymer networks

PubMed Central

Abu-Elenain, Dalia; Lewis, Steven H.; Stansbury, Jeffrey W.

2013-01-01

Objectives This study seeks to correlate the interrelated properties of conversion, shrinkage, modulus and stress as dimethacrylate networks transition from rubbery to glassy states during photopolymerization. Methods An unfilled BisGMA/TEGDMA resin was photocured for various irradiation intervals (7–600 s) to provide controlled levels of immediate conversion, which was monitored continuously for 10 min. Fiber optic near-infrared spectroscopy permitted coupling of real-time conversion measurement with dynamic polymerization shrinkage (linometer), modulus (dynamic mechanical analyzer) and stress (tensometer) development profiles. Results The varied irradiation conditions produced final conversion ranging from 6 % to more than 60 %. Post-irradiation conversion (dark cure) was quite limited when photopolymerization was interrupted either at very low or very high levels of conversion while significant dark cure contributions were possible for photocuring reactions suspended within the post-gel, rubbery regime. Analysis of conversion-based property evolution during and subsequent to photocuring demonstrated that the shrinkage rate increased significantly at about 40 % conversion followed by late-stage suppression in the conversion-dependent shrinkage rate that begins at about 45–50 % conversion. The gradual vitrification process over this conversion range is evident based on the broad but well-defined inflection in the modulus versus conversion data. As limiting conversion is approached, modulus and, to a somewhat lesser extent, stress rise precipitously as a result of vitrification with the stress profile showing little if any late-stage suppression as seen with shrinkage. Significance Near the limiting conversion for this model resin, the volumetric polymerization shrinkage rate slows while an exponential rise in modulus promotes the vitrification process that appears to largely dictate stress development. PMID:24080378

Design of video interface conversion system based on FPGA

NASA Astrophysics Data System (ADS)

Zhao, Heng; Wang, Xiang-jun

2014-11-01

This paper presents a FPGA based video interface conversion system that enables the inter-conversion between digital and analog video. Cyclone IV series EP4CE22F17C chip from Altera Corporation is used as the main video processing chip, and single-chip is used as the information interaction control unit between FPGA and PC. The system is able to encode/decode messages from the PC. Technologies including video decoding/encoding circuits, bus communication protocol, data stream de-interleaving and de-interlacing, color space conversion and the Camera Link timing generator module of FPGA are introduced. The system converts Composite Video Broadcast Signal (CVBS) from the CCD camera into Low Voltage Differential Signaling (LVDS), which will be collected by the video processing unit with Camera Link interface. The processed video signals will then be inputted to system output board and displayed on the monitor.The current experiment shows that it can achieve high-quality video conversion with minimum board size.

Anaerobic Digestion.

PubMed

Liebetrau, Jan; Sträuber, Heike; Kretzschmar, Jörg; Denysenko, Velina; Nelles, Michael

2017-04-09

The term anaerobic digestion usually refers to the microbial conversion of organic material to biogas, which mainly consists of methane and carbon dioxide. The technical application of the naturally-occurring process is used to provide a renewable energy carrier and - as the substrate is often waste material - to reduce the organic matter content of the substrate prior to disposal.Applications can be found in sewage sludge treatment, the treatment of industrial and municipal solid wastes and wastewaters (including landfill gas utilization), and the conversion of agricultural residues and energy crops.For biorefinery concepts, the anaerobic digestion (AD) process is, on the one hand, an option to treat organic residues from other production processes. Concomitant effects are the reduction of organic carbon within the treated substance, the conversion of nitrogen and sulfur components, and the production of an energy-rich gas - the biogas. On the other hand, the multistep conversion of complex organic material offers the possibility of interrupting the conversion chain and locking out intermediates for utilization as basic material within the chemical industry.

Self-reference, emotion inhibition and somatosensory disturbance: preliminary investigation of network perturbations in conversion disorder.

PubMed

Monsa, R; Peer, M; Arzy, S

2018-06-01

Conversion disorder (CD), or functional neurological disorder, is manifested as a neurological disturbance that is not macroscopically visible on clinical structural neuroimaging and is instead ascribed to underlying psychological stress. Known for many years in neuropsychiatry, a comprehensive explanation of the way in which psychological stress leads to a neurological deficit of a structural-like origin is still lacking. We applied whole-brain network-based data-driven analyses on resting-state functional magnetic resonance imaging, recorded in seven patients with acute-onset, stroke-like CD with unilateral paresis and hypoesthesia as compared with 15 age-matched healthy controls. We used a clustering analysis to measure functional connectivity (FC) strength within 10 different brain networks, as well as between these networks. Finally, we tested FC of specific brain regions that are known to be involved in CD. We found a significant increase in FC strength only within the default-mode network (DMN), which manages self-referential processing. Examination of inter-connectivity between networks showed a structure of disturbed connectivity, which included decreased connectivity between the DMN and limbic/salience network, increased connectivity between the limbic/salience network and body-related temporo-parieto-occipital junction network, decreased connectivity between the temporo-parieto-occipital junction and memory-related medial temporal lobe, and decreased connectivity between the medial temporal lobe and sensorimotor network. Region-specific FC analysis showed increased connectivity between the hippocampus and DMN. These preliminary results of disturbances in brain networks related to memory, emotions and self-referential processing, and networks involved in motor planning and execution, suggest a role of these cognitive functions in the psychopathology of CD. © 2018 EAN.

Special involuntary conversion situations involving timberland

Treesearch

William C. Siegal

2001-01-01

If standing timber is destroyed or stolen, or if forest land is condemned for public use, the owner may be entitled to take a deduction on his or her income tax return. These types of losses are called involuntary conversions. In previous National Woodlands articles I've discussed in detail casualty losses, which represent the major type of timber involuntary...

"Are You a Computer?" Opening Exchanges in Virtual Reference Shape the Potential for Teaching

ERIC Educational Resources Information Center

Dempsey, Paula R.

2016-01-01

Academic reference librarians frequently work with students who are not aware of their professional roles. In online interactions, a student might not even realize that the librarian is a person. The ways students initiate conversations reveal their understanding of the mutual roles involved in reference encounters. Conversation analysis of live…

Latino Families and Parental Involvement: A Case Study of Home Literature Conversations in a Primary Bilingual Classroom

ERIC Educational Resources Information Center

Quinones, Anna M.

2009-01-01

This dissertation study describes and interprets the dialogue between Latino parents and their children during home literature conversations. The participating students were enrolled in my first and second grade classroom in East Los Angeles, California. I was guided by the following research questions in this qualitative teacher research study:…

Relative Kerf and Sawing Variation Values for Some Hardwood Sawing Machines

Treesearch

Philip H. Steele; Michael W. Wade; Steven H. Bullard; Philip A. Araman

1992-01-01

Information on the conversion efficiency of sawing machines is important to those involved in the management, maintenance, and design of sawmills. Little information on the conversion characteristics of hardwood sawing machines has been available. This study, based on 266 studies of 6 machine types, provides an analysis of the machine characteristics of kerf width,...

High-yield conversion of (R)-2-octanol from the corresponding racemate by stereoinversion using Candida rugosa.

PubMed

Nie, Yao; Xu, Yan; Qing Mu, Xiao; Tang, Yan; Jiang, Juan; Hao Sun, Zhi

2005-01-01

Whole cells of Candida rugosa catalyzed the conversion of (R)-2-octanol from the corresponding racemate with the optical purity of 97% e.e. and yield of 92% in 10 h. The product was formed through a stereoinversion involving enantioselective oxidation and asymmetric reduction with 2-octanone as the intermediate.

Perspectives on magnetic reconnection

PubMed Central

Yamada, Masaaki

2016-01-01

Magnetic reconnection is a topological rearrangement of magnetic field that occurs on time scales much faster than the global magnetic diffusion time. Since the field lines break on microscopic scales but energy is stored and the field is driven on macroscopic scales, reconnection is an inherently multi-scale process that often involves both magnetohydrodynamic (MHD) and kinetic phenomena. In this article, we begin with the MHD point of view and then describe the dynamics and energetics of reconnection using a two-fluid formulation. We also focus on the respective roles of global and local processes and how they are coupled. We conclude that the triggers for reconnection are mostly global, that the key energy conversion and dissipation processes are either local or global, and that the presence of a continuum of scales coupled from microscopic to macroscopic may be the most likely path to fast reconnection. PMID:28119547

Transdifferentiation and reprogramming: Overview of the processes, their similarities and differences.

PubMed

Cieślar-Pobuda, Artur; Knoflach, Viktoria; Ringh, Mikael V; Stark, Joachim; Likus, Wirginia; Siemianowicz, Krzysztof; Ghavami, Saeid; Hudecki, Andrzej; Green, Jason L; Łos, Marek J

2017-07-01

Reprogramming, or generation of induced pluripotent stem (iPS) cells (functionally similar to embryonic stem cells or ES cells) by the use of transcription factors (typically: Oct3/4, Sox2, c-Myc, Klf4) called "Yamanaka factors" (OSKM), has revolutionized regenerative medicine. However, factors used to induce stemness are also overexpressed in cancer. Both, ES cells and iPS cells cause teratoma formation when injected to tissues. This raises a safety concern for therapies based on iPS derivates. Transdifferentiation (lineage reprogramming, or -conversion), is a process in which one mature, specialized cell type changes into another without entering a pluripotent state. This process involves an ectopic expression of transcription factors and/or other stimuli. Unlike in the case of reprogramming, tissues obtained by this method do not carry the risk of subsequent teratomagenesis. Copyright © 2017 Elsevier B.V. All rights reserved.

Flow-through biological conversion of lignocellulosic biomass

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

Herring, Christopher D.; Liu, Chaogang; Bardsley, John

2014-07-01

The present invention is directed to a process for biologically converting carbohydrates from lignocellulosic biomass comprising the steps of: suspending lignocellulosic biomass in a flow-through reactor, passing a reaction solution into the reactor, wherein the solution is absorbed into the biomass substrate and at least a portion of the solution migrates through said biomass substrate to a liquid reservoir, recirculating the reaction solution in the liquid reservoir at least once to be absorbed into and migrate through the biomass substrate again. The biological converting of the may involve hydrolyzing cellulose, hemicellulose, or a combination thereof to form oligosaccharides, monomelic sugars,more » or a combination thereof; fermenting oligosaccharides, monomelic sugars, or a combination thereof to produce ethanol, or a combination thereof. The process can further comprise removing the reaction solution and processing the solution to separate the ethanol produced from non-fermented solids.« less

Perspectives on magnetic reconnection

DOE PAGES

Zweibel, Ellen G.; Yamada, Masaaki

2016-12-07

Magnetic reconnection is a topological rearrangement of magnetic field that occurs on time scales much faster than the global magnetic diffusion time. Since the field lines break on microscopic scales but energy is stored and the field is driven on macroscopic scales, reconnection is an inherently multi-scale process that often involves both magnetohydrodynamic (MHD) and kinetic phenomena. In this article, we begin with the MHD point of view and then describe the dynamics and energetics of reconnection using a two-fluid formulation. We also focus on the respective roles of global and local processes and how they are coupled. Here, wemore » conclude that the triggers for reconnection are mostly global, that the key energy conversion and dissipation processes are either local or global, and that the presence of a continuum of scales coupled from microscopic to macroscopic may be the most likely path to fast reconnection.« less

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

Lilga, Michael A.; Padmaperuma, Asanga B.; Auberry, Deanna L.

We studied a new process for direct conversion of either levulinic acid (LA) or γ-valerolactone (GVL) to hydrocarbon fuel precursors. The process involves passing an aqueous solution of LA or GVL containing a reducing agent, such as ethylene glycol or formic acid, over a ketonization catalyst at 380–400 °C and atmospheric pressure to form a biphasic liquid product. The organic phase is significantly oligomerized and deoxygenated and comprises a complex mixture of open-chain alkanes and olefins, aromatics, and low concentrations of ketones, alcohols, ethers, and carboxylates or lactones. Carbon content in the aqueous phase decreases with decreasing feed rate; themore » aqueous phase can be reprocessed through the same catalyst to form additional organic oils to improve carbon yield. Catalysts are readily regenerated to restore initial activity. Furthermore, the process might be valuable in converting cellulosics to biorenewable gasoline, jet, and diesel fuels as a means to decrease petroleum use and decrease greenhouse gas emissions.« less

Biodiesel production with special emphasis on lipase-catalyzed transesterification.

PubMed

Bisen, Prakash S; Sanodiya, Bhagwan S; Thakur, Gulab S; Baghel, Rakesh K; Prasad, G B K S

2010-08-01

The production of biodiesel by transesterification employing acid or base catalyst has been industrially accepted for its high conversion and reaction rates. Downstream processing costs and environmental problems associated with biodiesel production and byproducts recovery have led to the search for alternative production methods. Recently, enzymatic transesterification involving lipases has attracted attention for biodiesel production as it produces high purity product and enables easy separation from the byproduct, glycerol. The use of immobilized lipases and immobilized whole cells may lower the overall cost, while presenting less downstream processing problems, to biodiesel production. The present review gives an overview on biodiesel production technology and analyzes the factors/methods of enzymatic approach reported in the literature and also suggests suitable method on the basis of evidence for industrial production of biodiesel.

The mere exposure effect and recognition depend on the way you look!

PubMed

Willems, Sylvie; Dedonder, Jonathan; Van der Linden, Martial

2010-01-01

In line with Whittlesea and Price (2001), we investigated whether the memory effect measured with an implicit memory paradigm (mere exposure effect) and an explicit recognition task depended on perceptual processing strategies, regardless of whether the task required intentional retrieval. We found that manipulation intended to prompt functional implicit-explicit dissociation no longer had a differential effect when we induced similar perceptual strategies in both tasks. Indeed, the results showed that prompting a nonanalytic strategy ensured performance above chance on both tasks. Conversely, inducing an analytic strategy drastically decreased both explicit and implicit performance. Furthermore, we noted that the nonanalytic strategy involved less extensive gaze scanning than the analytic strategy and that memory effects under this processing strategy were largely independent of gaze movement.

Intellectual Interest Mediates Gene-by-SES Interaction on Adolescent Academic Achievement

PubMed Central

Tucker-Drob, Elliot M.; Harden, K. Paige

2011-01-01

Recent studies have demonstrated that genetic influences on cognitive ability and academic achievement are larger for children raised in higher socioeconomic status (SES) homes. However, little work has been done to document the psychosocial processes that underlie this gene-by-environment interaction. One process may involve the conversion of intellectual interest into academic achievement. Analyses of data from 777 pairs of 17-year-old twins indicated that gene-by-SES effects on achievement scores can be accounted for by stronger influences of genes for intellectual interest on achievement at higher levels of SES. These findings are consistent with the hypothesis that higher SES affords greater opportunity for children to seek out and benefit from learning experiences that are congruent with their genetically influenced intellectual interests. PMID:22288554

End-of-life decision-making for children with severe developmental disabilities: The parental perspective.

PubMed

Zaal-Schuller, I H; de Vos, M A; Ewals, F V P M; van Goudoever, J B; Willems, D L

2016-01-01

The objectives of this integrative review were to understand how parents of children with severe developmental disorders experience their involvement in end-of-life decision-making, how they prefer to be involved and what factors influence their decisions. We searched MEDLINE, EMBASE, CINAHL and PsycINFO. The search was limited to articles in English or Dutch published between January 2004 and August 2014. We included qualitative and quantitative original studies that directly investigated the experiences of parents of children aged 0-18 years with severe developmental disorders for whom an end-of-life decision had been considered or made. We identified nine studies that met all inclusion criteria. Reportedly, parental involvement in end-of-life decision-making varied widely, ranging from having no involvement to being the sole decision-maker. Most parents preferred to actively share in the decision-making process regardless of their child's specific diagnosis or comorbidity. The main factors that influenced parents in their decision-making were: their strong urge to advocate for their child's best interests and to make the best (possible) decision. In addition, parents felt influenced by their child's visible suffering, remaining quality of life and the will they perceived in their child to survive. Most parents of children with severe developmental disorders wish to actively share in the end-of-life decision-making process. An important emerging factor in this process is the parents' feeling that they have to stand up for their child's interests in conversations with the medical team. Copyright © 2015 Elsevier Ltd. All rights reserved.

Learning science in small groups: The relationship of conversation to conceptual understanding

NASA Astrophysics Data System (ADS)

McDonald, James Tarleton

The purpose of this study was to investigate the relationship between conversation and conceptual understanding of erosion. The objective of this study was to investigate how fifth grade students' conceptions of erosion changed while they used stream tables and worked in groups of four within an inquiry-based curriculum. This study used symbolic interactionism and sociocognitive frameworks to interpret science learning in the elementary classroom. The research focused on the conceptual understanding of the focal group students, their use of classroom discourse to talk about their understandings of erosion, and the expertise that emerged while using stream tables. This study took place over a one-semester long study on erosion. Key informants were eight fifth graders. The data sources consisted of children's journals; transcripts of audiotaped interviews with the key informants before, during, and after the erosion unit; transcripts of videotapes of the students using the stream tables; and field notes recording children's discourse and activity. Individual and group cases were constructed during the study. The knowledge of the eight focal group children was placed on a hierarchy of conceptual understanding that contained 8 components of the erosion process. All four of the students whose ideas were examined in depth gained in their conceptual understanding of erosion. Students' individual expertise enhanced their own conceptual understanding. The contribution of classroom discourse and expertise to conceptual understanding differed between the two focal groups. Group 1 used essential expertise to sustain generative conversations, maximizing their learning opportunities. Students in Group 1 got along with one another, rotated assigned roles and jobs, and were able to start their own generative conversations. Members of Group 1 asked generative questions, connected stream table events to real life situations, and involved everyone in the group. Group 2 engaged in a predominance of procedural discourse and had fewer learning opportunities. Group 2 had two dominant personalities who developed a conflict over roles and jobs, keeping their peers out of the conversation. Students in Group 2 had generative conversations, but these were not sustained due to the lack of acknowledgment of peer expertise and the starting their own generative conversations.

In My Opinion. A New Sign Conversion for Geometrical Optics.

ERIC Educational Resources Information Center

Ditteon, Richard

1993-01-01

Introduces a new sign convention for the object and image distances involving mirrors and lenses. Proposes that the method is easier for students to understand and remember and that it helps clarify the physics concepts involved. (MDH)

Pressure-Volume Work Exercises Illustrating the First and Second Laws.

ERIC Educational Resources Information Center

Hoover, William G.; Moran, Bill

1979-01-01

Presented are two problem exercises involving rapid compression and expansion of ideal gases which illustrate the first and second laws of thermodynamics. The first problem involves the conversion of gravitational energy into heat through mechanical work. The second involves the mutual interaction of two gases through an adiabatic piston. (BT)

Investigating Electrochemical Processes in Secondary Batteries

NASA Astrophysics Data System (ADS)

Cama, Christina A.

For the past twenty-six years, the lithium-ion battery has been the most popular recharge- able battery for portable devices and electric vehicles. Despite its success, the energy storage capability of lithium-ion batteries (LIBs) is significantly limited by both the electrodes and electrolytes employed. Typical LIBs rely on intercalation-type electrodes, that are not capable of storing more than 1 Li+ per formula unit. The energy storage capability of LIBs can be improved through the application of conversion-type materials and beyond lithium chemistries. This research involves multiple projects which explore the electrochemistry of conversion electrodes, magnesium-ion chemistry, and lithium-sulfur chemistry. Application of conversion-electrodes like copper ferrite, CuFe2O4, and magnetite, Fe3O4, are capable of lithium storage over five times greater than that achieved by electrodes used in commercial LIBs. The drawback to utilizing the conversion mechanism is that significant energy storage capability is lost during charge. In this research, X- ray characterization methods, including X-ray Diffraction (XRD) and X-ray Absorption Spectroscopy (XAS) are used to elucidate the lithiation and delithiation mechanism for CuFe2O4 and to understand the source of the irreversibility. These experiments provide significant insight into the reduction processes and cation migration within the structure. During lithiation, CuFe2O4 undergoes a three-step reduction mechanism involving (1) lithiation of CuFe2O4, (2) extrusion of copper metal nanoparticles and formation of rock- salt LiFeO2, followed by the (3) formation of iron metal nanoparticles. Upon delithiation, XAS spectra clearly demonstrate the feasibility of Fe0 oxidation to a rock-salt iron oxide; however, Cu0 oxidation is not observed. Additional experiments explored the kinetic limitations of lithiating Fe3O4 nanoparticles, with different crystallite sizes. The experiments demonstrate that the kinetics of the lithiation mechanism are influenced by the electroactive material’s agglomerate and crystallite size. The rate of lithiation involving small crystallites is dependent on diffusion within the agglomerates; however, as the crystallite size increases, the lithiation rate is inhibited by diffusion within both the agglomerate and the crystallite. Battery chemistries beyond lithium can also lead to energy storage capabilities an order of magnitude higher than LIBs. Both magnesium-ion and lithium-sulfur battery chemistries are investigated in this dissertation. The properties of ionic liquid electrolytes are explored as safer alternatives to harmful Grignard-reagent electrolytes commonly used for magnesium chemistries. Electrochemical evaluation of the ionic liquid electrolytes found that although better conductivity can be achieved with unsaturated electrolytes like imidizolium based electrolytes, greater oxidative voltages are possible with saturated electrolytes like the piperidinium and pyridinium based electrolytes. The higher oxidative voltage is a promising attribute for high voltage applications. Cathode additives, including FeS2 and microporous carbon, are studied to inhibit polysulfide dissolution within the electrolyte of Li|S batteries. Although FeS2 exhibited promising electrochemistry as its own cathode, it was found to be an ineffective additive within sulfur cathodes. Instead, the properties of microporous carbons are explored to identify an appropriate carbon additive to both increase conductivity and impede polysulfide dissolution. A wood based carbon exhibited high capacity and long cycle life at low rate compared to conventional microporous carbons. As a whole, this research has provided valuable insight into the electrochemical processes taking place within a battery, as well as the factors which affect these processes. Electrochemical, spectroscopic, and various scattering methods are used to probe processes which span from the reactions occurring within the electrode to the redox reactions which define the voltage limitations of the electrolyte. These studies demonstrate the impact of each battery component on the overall electrochemical performance and provide fundamental insight into battery operation.

Efficient co-conversion process of chicken manure into protein feed and organic fertilizer by Hermetia illucens L. (Diptera: Stratiomyidae) larvae and functional bacteria.

PubMed

Xiao, Xiaopeng; Mazza, Lorenzo; Yu, Yongqiang; Cai, Minmin; Zheng, Longyu; Tomberlin, Jeffery K; Yu, Jeffrey; van Huis, Arnold; Yu, Ziniu; Fasulo, Salvatore; Zhang, Jibin

2018-07-01

A chicken manure management process was carried out through co-conversion of Hermetia illucens L. larvae (BSFL) with functional bacteria for producing larvae as feed stuff and organic fertilizer. Thirteen days co-conversion of 1000 kg of chicken manure inoculated with one million 6-day-old BSFL and 10 9  CFU Bacillus subtilis BSF-CL produced aging larvae, followed by eleven days of aerobic fermentation inoculated with the decomposing agent to maturity. 93.2 kg of fresh larvae were harvested from the B. subtilis BSF-CL-inoculated group, while the control group only harvested 80.4 kg of fresh larvae. Chicken manure reduction rate of the B. subtilis BSF-CL-inoculated group was 40.5%, while chicken manure reduction rate of the control group was 35.8%. The weight of BSFL increased by 15.9%, BSFL conversion rate increased by 12.7%, and chicken manure reduction rate increased by 13.4% compared to the control (no B. subtilis BSF-CL). The residue inoculated with decomposing agent had higher maturity (germination index >92%), compared with the no decomposing agent group (germination index ∼86%). The activity patterns of different enzymes further indicated that its production was more mature and stable than that of the no decomposing agent group. Physical and chemical production parameters showed that the residue inoculated with the decomposing agent was more suitable for organic fertilizer than the no decomposing agent group. Both, the co-conversion of chicken manure by BSFL with its synergistic bacteria and the aerobic fermentation with the decomposing agent required only 24 days. The results demonstrate that co-conversion process could shorten the processing time of chicken manure compared to traditional compost process. Gut bacteria could enhance manure conversion and manure reduction. We established efficient manure co-conversion process by black soldier fly and bacteria and harvest high value-added larvae mass and biofertilizer. Copyright © 2018 Elsevier Ltd. All rights reserved.

Direct 1H NMR evidence of spin-rotation coupling as a source of para → ortho-H2 conversion in diamagnetic solvents.

PubMed

Terenzi, Camilla; Bouguet-Bonnet, Sabine; Canet, Daniel

2017-04-21

At ambient temperature, conversion from 100% enriched para-hydrogen (p-H 2 ; singlet state) to ortho-hydrogen (o-H 2 ; triplet state) leads necessarily to the thermodynamic equilibrium proportions: 75% of o-H 2 and 25% of p-H 2 . When p-H 2 is dissolved in a diamagnetic organic solvent, conversion is very slow and can be considered as arising from nuclear spin relaxation phenomena. A first relaxation mechanism, specific to the singlet state and involving a combination of auto-correlation and cross correlation spectral densities, can be retained: randomly fluctuating magnetic fields due to inter-molecular dipolar interactions. We demonstrate here that (i) this dipolar mechanism is not sufficient for accounting for the para→ortho conversion rate, (ii) spin-rotation interaction, an intra-molecular mechanism, behaves similarly to random-field interaction and, thus, may be involved in the singlet relaxation rate. Also, as the para→ortho conversion is monitored by proton nuclear magnetic resonance (NMR) of dissolved o-H 2 (p-H 2 is NMR-silent), one has to account for H 2 exchange between the liquid phase and the gas phase within the NMR tube, as well as for dissolution effects. Experimental evidence of the above statements is brought here in the case of two organic solvents: acetone-d 6 and carbon disulfide. The observed temperature dependence of the para→ortho conversion rate shows that spin-rotation can be the dominant contribution to the p-H 2 relaxation rate in the absence of tangible dipolar interactions. Our findings shed new light on the "mysterious" mechanism of the para→ortho conversion which has been searched for several decades.

Evaluation of parallel milliliter-scale stirred-tank bioreactors for the study of biphasic whole-cell biocatalysis with ionic liquids.

PubMed

Dennewald, Danielle; Hortsch, Ralf; Weuster-Botz, Dirk

2012-01-01

As clear structure-activity relationships are still rare for ionic liquids, preliminary experiments are necessary for the process development of biphasic whole-cell processes involving these solvents. To reduce the time investment and the material costs, the process development of such biphasic reaction systems would profit from a small-scale high-throughput platform. Exemplarily, the reduction of 2-octanone to (R)-2-octanol by a recombinant Escherichia coli in a biphasic ionic liquid/water system was studied in a miniaturized stirred-tank bioreactor system allowing the parallel operation of up to 48 reactors at the mL-scale. The results were compared to those obtained in a 20-fold larger stirred-tank reactor. The maximum local energy dissipation was evaluated at the larger scale and compared to the data available for the small-scale reactors, to verify if similar mass transfer could be obtained at both scales. Thereafter, the reaction kinetics and final conversions reached in different reactions setups were analysed. The results were in good agreement between both scales for varying ionic liquids and for ionic liquid volume fractions up to 40%. The parallel bioreactor system can thus be used for the process development of the majority of biphasic reaction systems involving ionic liquids, reducing the time and resource investment during the process development of this type of applications. Copyright © 2011. Published by Elsevier B.V.

Single-photon frequency conversion via cascaded quadratic nonlinear processes

NASA Astrophysics Data System (ADS)

Xiang, Tong; Sun, Qi-Chao; Li, Yuanhua; Zheng, Yuanlin; Chen, Xianfeng

2018-06-01

Frequency conversion of single photons is an important technology for quantum interface and quantum communication networks. Here, single-photon frequency conversion in the telecommunication band is experimentally demonstrated via cascaded quadratic nonlinear processes. Using cascaded quasi-phase-matched sum and difference frequency generation in a periodically poled lithium niobate waveguide, the signal photon of a photon pair from spontaneous down-conversion is precisely shifted to identically match its counterpart, i.e., the idler photon, in frequency to manifest a clear nonclassical dip in the Hong-Ou-Mandel interference. Moreover, quantum entanglement between the photon pair is maintained after the frequency conversion, as is proved in time-energy entanglement measurement. The scheme is used to switch single photons between dense wavelength-division multiplexing channels, which holds great promise in applications in realistic quantum networks.

Transitional polytherapy: tricks of the trade for monotherapy to monotherapy AED conversions.

PubMed

Garnett, William R; St Louis, Erik K; Henry, Thomas R; Bramley, Thomas

2009-06-01

The goal of epilepsy therapy is to help patients achieve seizure freedom without adverse effects. While monotherapy is preferable in epilepsy treatment, many patients fail a first drug due to lack of efficacy or failure to tolerate an initial medication, necessitating an alteration in therapy. Sudden changes between monotherapies are rarely feasible and sometimes deleterious given potential hazards of acute seizure exacerbation or intolerable adverse effects. The preferred method for converting between monotherapies is transitional polytherapy, a process involving initiation of a new antiepileptic drug (AED) and adjusting it toward a target dose while maintaining or reducing the dose of the baseline medication. A fixed-dose titration strategy of maintaining the baseline drug dose while titrating the new medication is preferable when breakthrough seizures are occurring and no adverse effects are present. However, a flexible titration strategy involving reduction of the baseline drug dose to ensure adequate tolerability of the new adjunctive medication is preferred when patients are already experiencing adverse effects. This article reviews pharmacokinetic considerations pertinent for ensuring successful transitional polytherapy with the standard and newer antiepileptic drugs. Practical consensus recommendations "from an expect panel (SPECTRA, Study by a Panel of Experts Considerations for Therapy Replacement and Antiepileptics) for a successful monotherapy" AED conversions are then summarized. Transitional polytherapy is most successful when clinicians appropriately manage the titration strategy and consider pharmacokinetic factors germane to the baseline and new adjunctive medication.

Particle simulation of electromagnetic emissions from electrostatic instability driven by an electron ring beam on the density gradient

NASA Astrophysics Data System (ADS)

Horký, Miroslav; Omura, Yoshiharu; Santolík, Ondřej

2018-04-01

This paper presents the wave mode conversion between electrostatic and electromagnetic waves on the plasma density gradient. We use 2-D electromagnetic code KEMPO2 implemented with the generation of density gradient to simulate such a conversion process. In the dense region, we use ring beam instability to generate electron Bernstein waves and we study the temporal evolution of wave spectra, velocity distributions, Poynting flux, and electric and magnetic energies to observe the wave mode conversion. Such a conversion process can be a source of electromagnetic emissions which are routinely measured by spacecraft on the plasmapause density gradient.

Chart of conversion factors: From English to metric system and metric to English system

USGS Publications Warehouse

,

1976-01-01

The conversion factors in the following tables are for conversion of our customary (English) units of measurement to SI*units, and for convenience, reciprocals are shown for converting SI units back to the English system. The first table contains rule-of-thumb figures, useful for "getting the feel" of SI units or mental estimation. The succeeding tables contain factors accurate to 3 or more significant figures. Please refer to known reference volumes for additional accuracy, as well as for factors dealing with other scientific notation involving SI units.

ALTERATION OF GENE CONVERSION PATTERNS IN Sordaria fimicola BY SUPPLEMENTATION WITH DNA BASES*

PubMed Central

Kitani, Y.; Olive, Lindsay S.

1970-01-01

Supplementation with DNA bases in crosses of Sordaria fimicola heterozygous for spore color markers (g1, h2) within the gray-spore (g) locus has been found to cause significant alterations in patterns of gene conversion at the two mutant sites. Each base had its own characteristic effect in altering the conversion pattern, and responses of the two mutant sites to the four bases were different in several ways. Also, the responses of the two involved chromatids of the meiotic bivalent were different. PMID:5273454

Alteration of gene conversion patterns in Sordaria fimicola by supplementation with DNA bases.

PubMed

Kitani, Y; Olive, L S

1970-08-01

Supplementation with DNA bases in crosses of Sordaria fimicola heterozygous for spore color markers (g(1), h(2)) within the gray-spore (g) locus has been found to cause significant alterations in patterns of gene conversion at the two mutant sites. Each base had its own characteristic effect in altering the conversion pattern, and responses of the two mutant sites to the four bases were different in several ways. Also, the responses of the two involved chromatids of the meiotic bivalent were different.

Thermochemical recovery of heat contained in flue gases by means of bioethanol conversion

NASA Astrophysics Data System (ADS)

Pashchenko, D. I.

2013-06-01

In the present paper consideration is being given to the use of bioethanol in the schemes of thermochemical recovery of heat contained in exit flue gases. Schematic diagrams illustrate the realization of thermochemical heat recovery by implementing ethanol steam conversion and conversion of ethanol by means of products of its complete combustion. The feasibility of attaining a high degree of recovery of heat contained in flue gases at the moderate temperature (up to 450°C) of combustion components is demonstrated in the example of the energy balance of the system for thermochemical heat recovery. The simplified thermodynamic analysis of the process of ethanol steam conversion was carried out in order to determine possible ranges of variation of process variables (temperature, pressure, composition) of a reaction mixture providing the efficient heat utilization. It was found that at the temperature above 600 K the degree of ethanol conversion is near unity. The equilibrium composition of products of reaction of ethanol steam conversion has been identified for different temperatures at which the process occurs at the ratio H2O/EtOH = 1 and at the pressure of 0.1 MPa. The obtained results of calculation agree well with the experimental data.

Conversive disorders among children and adolescents: towards new "complementarist" paradigms?

PubMed

Ouss, L; Tordjman, E

2014-10-01

This paper aims to describe current questions concerning conversive disorders among children and adolescents. We first describe prevalence and clinical characteristics of these. Many unresolved questions remain. Why do patients show excess, or loss of function? Attachment theory offers a relevant framework to answer this question. Does neurobiology of conversion disorders shed light on conversive processes? Current neurobiological research paradigms focus on the symptom, trying to infer processes, instead of proposing paradigms that test theoretical hypotheses. The most convincing theoretical framework that has already proposed a coherent theory of conversion is a psychodynamic one, which has not yet been tested with neurobiological paradigms. The interest of studying child and adolescent conversive disorders is to provide a means to more deeply investigate the two challenges we face: theoretical, and clinical ones. It provides the opportunity to access a pathopsychological process at its roots, not yet hidden by many defensive, rationalizing attitudes, and to better explore environmental features. We propose a "complementarist" model, which allows the combination of different approaches (neural, cognitive, environmental, attachment, intra-psychic) and permits proposal of different levels of therapeutic targets and means. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

'Those were taken away and given money': power and reward expectations' influence in the selection of village health teams in rural Uganda.

PubMed

Turinawe, Emmanueil B

2016-01-01

With the renewed call for community participation in health interventions after the Alma Ata Declaration, interest has been raised in volunteer community health workers (CHWs) acting as representatives of local communities. The present study interrogates the dynamic interface between local communities and the government in the selection of CHW volunteers in a rural community. Data were collected through participant observation of community events, 35 in-depth interviews, 20 focus groups and 15 informal conversations. A review of documents about Luwero district was also an important source of data. Ambiguous national guidelines and poor supervision of the selection process enabled the powerful community leaders to influence the selection of village health teams (VHTs). Intended to achieve community involvement, the selection process produced a disconnect in the local community where many members saw the selected VHTs as having been 'taken away'. Community involvement in the selection of VHTs took a form that, instead of empowering the local community, reinforced the responsibility of those in power and thus maintained the asymmetrical status quo.

Can a Spanish science education journal become international? the case of Enseñanza de las Ciencias

NASA Astrophysics Data System (ADS)

Espinet, Mariona; Izquierdo, Mercè; Garcia-Pujol, Clara

2015-12-01

In this paper we discuss the case of the science education research journal Enseñanza de las Ciencias (EC) around the issue of its internationalization and the consequences this process has had and is still having on the use and preservation of different languages and more specifically the Castilian (Spanish) language. We first frame the concept of globalization and internationalization, and identify three important dimensions involved in the process of internationalization of EC such as language use, actors involved and resources available. Secondly, we address the historical evolution of EC along three phases of internationalization. In each phase we discuss the tensions experienced in relevant internationalization dimensions focusing particularly on the use of languages. We conclude by advocating a plurilingual and multicultural model for a science education research journal as an alternative to the hegemony of international English written journals. In doing so we want to continue the conversation on the role that local and national science education research journals have in promoting science education around the world.

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

Zee, Ralph; Schindler, Anton; Duke, Steve

The objective of this project is to conduct research to determine the feasibility of using alternate fuel sources for the production of cement. Successful completion of this project will also be beneficial to other commercial processes that are highly energy intensive. During this report period, we have completed all the subtasks in the preliminary survey. Literature searches focused on the types of alternative fuels currently used in the cement industry around the world. Information was obtained on the effects of particular alternative fuels on the clinker/cement product and on cement plant emissions. Federal regulations involving use of waste fuels weremore » examined. Information was also obtained about the trace elements likely to be found in alternative fuels, coal, and raw feeds, as well as the effects of various trace elements introduced into system at the feed or fuel stage on the kiln process, the clinker/cement product, and concrete made from the cement. The experimental part of this project involves the feasibility of a variety of alternative materials mainly commercial wastes to substitute for coal in an industrial cement kiln in Lafarge NA and validation of the experimental results with energy conversion consideration.« less

Pollination: a key event controlling the expression of genes related to phytohormone biosynthesis during grapevine berry formation.

PubMed

Kühn, Nathalie; Arce-Johnson, Patricio

2012-01-01

Berry formation is the process of ovary conversion into a functional fruit, and is characterized by abrupt changes in the content of several phytohormones, associated with pollination and fertilization. Much effort has been made in order to improve our understanding of berry development, particularly from veraison to post-harvest time. However, the period of berry formation has been poorly investigated, despite its importance. Phytohormones are involved in the control of fruit formation; hence it is important to understand the regulation of their content at this stage. Grapevine is an excellent fleshy-fruit plant model since its fruits have particularities that differentiate them from those of commonly studied organisms. For instance, berries are prepared to cope with stress by producing several antioxidants and they are non-climacteric fruits. Also its genome is fully sequenced, which allows to identify genes involved in developmental processes. In grapevine, no link has been established between pollination and phytohormone biosynthesis, until recently. Here we highlight relevant findings regarding pollination effect on gene expression related to phytohormone biosynthesis, and present unpublished results showing how quickly this effect is achieved.